Clinical Experience With Image-Guided Radiotherapy in an Accelerated Partial Breast Intensity-Modulated Radiotherapy Protocol

International Nuclear Information System (INIS)

Leonard, Charles E.; Tallhamer, Michael M.S.; Johnson, Tim; Hunter, Kari C.M.D.; Howell, Kathryn; Kercher, Jane; Widener, Jodi; Kaske, Terese; Paul, Devchand; Sedlacek, Scot; Carter, Dennis L.

2010-01-01

Purpose: To explore the feasibility of fiducial markers for the use of image-guided radiotherapy (IGRT) in an accelerated partial breast intensity modulated radiotherapy protocol. Methods and Materials: Nineteen patients consented to an institutional review board approved protocol of accelerated partial breast intensity-modulated radiotherapy with fiducial marker placement and treatment with IGRT. Patients (1 patient with bilateral breast cancer; 20 total breasts) underwent ultrasound guided implantation of three 1.2- x 3-mm gold markers placed around the surgical cavity. For each patient, table shifts (inferior/superior, right/left lateral, and anterior/posterior) and minimum, maximum, mean error with standard deviation were recorded for each of the 10 BID treatments. The dose contribution of daily orthogonal films was also examined. Results: All IGRT patients underwent successful marker placement. In all, 200 IGRT treatment sessions were performed. The average vector displacement was 4 mm (range, 2-7 mm). The average superior/inferior shift was 2 mm (range, 0-5 mm), the average lateral shift was 2 mm (range, 1-4 mm), and the average anterior/posterior shift was 3 mm (range, 1 5 mm). Conclusions: This study shows that the use of IGRT can be successfully used in an accelerated partial breast intensity-modulated radiotherapy protocol. The authors believe that this technique has increased daily treatment accuracy and permitted reduction in the margin added to the clinical target volume to form the planning target volume.

Intensity modulated radiotherapy for breast cancer

International Nuclear Information System (INIS)

Riou, O.; Fenoglietto, P.; Lemanski, C.; Azria, D.

2012-01-01

Intensity modulated radiotherapy (IMRT) is a technique allowing dose escalation and normal tissue sparing for various cancer types. For breast cancer, the main goals when using IMRT were to improve dose homogeneity within the breast and to enhance coverage of complex target volumes. Nonetheless, better heart and lung protections are achievable with IMRT as compared to standard irradiation for difficult cases. Three prospective randomized controlled trials of IMRT versus standard treatment showed that a better breast homogeneity can translate into better overall cosmetic results. Dosimetric and clinical studies seem to indicate a benefit of IMRT for lymph nodes irradiation, bilateral treatment, left breast and chest wall radiotherapy, or accelerated partial breast irradiation. The multiple technical IMRT solutions available tend to indicate a widespread use for breast irradiation. Nevertheless, indications for breast IMRT should be personalized and selected according to the expected benefit for each individual. (authors)

Comparison of intensity-modulated radiotherapy and 3-dimensional conformal radiotherapy as adjuvant therapy for gastric cancer.

Science.gov (United States)

Minn, A Yuriko; Hsu, Annie; La, Trang; Kunz, Pamela; Fisher, George A; Ford, James M; Norton, Jeffrey A; Visser, Brendan; Goodman, Karyn A; Koong, Albert C; Chang, Daniel T

2010-08-15

The current study was performed to compare the clinical outcomes and toxicity in patients treated with postoperative chemoradiotherapy for gastric cancer using intensity-modulated radiotherapy (IMRT) versus 3-dimensional conformal radiotherapy (3D CRT). Fifty-seven patients with gastric or gastroesophageal junction cancer were treated postoperatively: 26 with 3D CRT and 31 with IMRT. Concurrent chemotherapy was capecitabine (n=31), 5-fluorouracil (5-FU) (n=25), or none (n=1). The median radiation dose was 45 Gy. Dose volume histogram parameters for kidney and liver were compared between treatment groups. The 2-year overall survival rates for 3D CRT versus IMRT were 51% and 65%, respectively (P=.5). Four locoregional failures occurred each in the 3D CRT (15%) and the IMRT (13%) patients. Grade>or=2 acute gastrointestinal toxicity was found to be similar between the 3D CRT and IMRT patients (61.5% vs 61.2%, respectively) but more treatment breaks were needed (3 vs 0, respectively). The median serum creatinine from before radiotherapy to most recent creatinine was unchanged in the IMRT group (0.80 mg/dL) but increased in the 3D CRT group from 0.80 mg/dL to 1.0 mg/dL (P=.02). The median kidney mean dose was higher in the IMRT versus the 3D CRT group (13.9 Gy vs 11.1 Gy; P=.05). The median kidney V20 was lower for the IMRT versus the 3D CRT group (17.5% vs 22%; P=.17). The median liver mean dose for IMRT and 3D CRT was 13.6 Gy and 18.6 Gy, respectively (P=.19). The median liver V30 was 16.1% and 28%, respectively (PCancer Society.

Intensity modulated radiotherapy (IMRT) with compensators

International Nuclear Information System (INIS)

Salz, H.; Wiezorek, T.; Scheithauer, M.; Kleen, W.; Schwedas, M.; Wendt, T.G.

2002-01-01

The irradiation with intensity-modulated fields is possible with static as well as dynamic methods. In our university hospital, the intensity-modulated radiotherapy (IMRT) with compensators was prepared and used for the first time for patient irradiation in July 2001. The compensators consist of a mixture of tin granulate and wax, which is filled in a milled negative mould. The treatment planning is performed with Helax-TMS (MDS Nordion). An additional software is used for editing the modulation matrix ('Modifix'). Before irradiation of the first patient, extensive measurements have been carried out in terms of quality assurance of treatment planning and production of compensators. The results of the verification measurements have shown that IMRT with compensators possesses high spatial and dosimetric exactness. The calculated dose distributions are applied correctly. The accuracy of the calculated monitor units is normally better than 3%; in small volumes, further dosimetric inaccuracies between calculated and measured dose distributions are mostly less than 3%. Therefore, the compensators contribute to the achievement of high-level IMRT even when apparatuses without MLC are used. This paper describes the use of the IMRT with compensators, presents the limits of this technology, and discusses the first practical experiences. (orig.) [de

Conformal radiotherapy by intensity modulation of pediatrics tumors; Radiotherapie conformationnelle par modulation d'intensite des tumeurs pediatriques

Energy Technology Data Exchange (ETDEWEB)

Leseur, J.; Le Prise, E. [Centre Eugene-Marquis, 35 - Rennes (France); Carrie, C. [Centre Leon Berard, 69 - Lyon (France); Bernier, V. [Centre Alexis-Vautrin, 54 - Nancy (France); Beneyton, V. [Centre Paul-Strauss, 67 - Strasbourg (France); Mahe, M.A.; Supiot, S. [Centre Rene-Gauducheau, 44 - Nantes (France)

2009-10-15

The objective of this study is to take stock on the validated and potential indications of the conformal radiotherapy with intensity modulation ( intensity modulated radiotherapy I.M.R.T.) in pediatrics and to propose recommendations for its use as well as the adapted dose constraints. About 40 to 50% of children treated for a cancer are irradiated. The I.M.R.T., by linear accelerator or helical tomo-therapy has for aim to give a homogenous dose to the target volume and to save organs at risk. Its use in pediatrics seems particularly interesting because of the complexity of target volumes and the closeness of organs at risk. In compensation for these positive elements, the importance of low doses irradiation given in big volumes makes fear event consequences on growth and an increased incidence of secondary cancers in children suffering from tumors with high cure rates and long life expectancy. (N.C.)

Guidelines for target volume definition in post-operative radiotherapy for prostate cancer, on behalf of the EORTC Radiation Oncology Group

International Nuclear Information System (INIS)

Poortmans, Philip; Bossi, Alberto; Vandeputte, Katia; Bosset, Mathieu; Miralbell, Raymond; Maingon, Philippe; Boehmer, Dirk; Budiharto, Tom; Symon, Zvi; Bergh, Alfons C.M. van den; Scrase, Christopher; Poppel, Hendrik van; Bolla, Michel

2007-01-01

The appropriate application of 3-D conformal radiotherapy, intensity modulated radiotherapy or image guided radiotherapy for patients undergoing post-operative radiotherapy for prostate cancer requires a standardisation of the target volume definition and delineation as well as standardisation of the clinical quality assurance procedures. Recommendations for this are presented on behalf of the European Organisation for Research and Treatment of Cancer (EORTC) Radiation Oncology Group and in addition to the already published guidelines for radiotherapy as the primary treatment

Comparison of simple and complex liver intensity modulated radiotherapy

International Nuclear Information System (INIS)

Lee, Mark T; Purdie, Thomas G; Eccles, Cynthia L; Sharpe, Michael B; Dawson, Laura A

2010-01-01

Intensity-modulated radiotherapy (IMRT) may allow improvement in plan quality for treatment of liver cancer, however increasing radiation modulation complexity can lead to increased uncertainties and requirements for quality assurance. This study assesses whether target coverage and normal tissue avoidance can be maintained in liver cancer intensity-modulated radiotherapy (IMRT) plans by systematically reducing the complexity of the delivered fluence. An optimal baseline six fraction individualized IMRT plan for 27 patients with 45 liver cancers was developed which provided a median minimum dose to 0.5 cc of the planning target volume (PTV) of 38.3 Gy (range, 25.9-59.5 Gy), in 6 fractions, while maintaining liver toxicity risk <5% and maximum luminal gastrointestinal structure doses of 30 Gy. The number of segments was systematically reduced until normal tissue constraints were exceeded while maintaining equivalent dose coverage to 95% of PTV (PTVD95). Radiotherapy doses were compared between the plans. Reduction in the number of segments was achieved for all 27 plans from a median of 48 segments (range 34-52) to 19 segments (range 6-30), without exceeding normal tissue dose objectives and maintaining equivalent PTVD95 and similar PTV Equivalent Uniform Dose (EUD(-20)) IMRT plans with fewer segments had significantly less monitor units (mean, 1892 reduced to 1695, p = 0.012), but also reduced dose conformity (mean, RTOG Conformity Index 1.42 increased to 1.53 p = 0.001). Tumour coverage and normal tissue objectives were maintained with simplified liver IMRT, at the expense of reduced conformity

A Dosimetric Evaluation of Conventional Helmet Field Irradiation Versus Two-Field Intensity-Modulated Radiotherapy Technique

International Nuclear Information System (INIS)

Yu, James B.; Shiao, Stephen L.; Knisely, Jonathan

2007-01-01

Purpose: To compare dosimetric differences between conventional two-beam helmet field irradiation (external beam radiotherapy, EBRT) of the brain and a two-field intensity-modulated radiotherapy (IMRT) technique. Methods and Materials: Ten patients who received helmet field irradiation at our institution were selected for study. External beam radiotherapy portals were planned per usual practice. Intensity-modulated radiotherapy fields were created using the identical field angles as the EBRT portals. Each brain was fully contoured along with the spinal cord to the bottom of the C2 vertebral body. This volume was then expanded symmetrically by 0.5 cm to construct the planning target volume. An IMRT plan was constructed using uniform optimization constraints. For both techniques, the nominal prescribed dose was 3,000 cGy in 10 fractions of 300 cGy using 6-MV photons. Comparative dose-volume histograms were generated for each patient and analyzed. Results: Intensity-modulated radiotherapy improved dose uniformity over EBRT for whole brain radiotherapy. The mean percentage of brain receiving >105% of dose was reduced from 29.3% with EBRT to 0.03% with IMRT. The mean maximum dose was reduced from 3,378 cGy (113%) for EBRT to 3,162 cGy (105%) with IMRT. The mean percent volume receiving at least 98% of the prescribed dose was 99.5% for the conventional technique and 100% for IMRT. Conclusions: Intensity-modulated radiotherapy reduces dose inhomogeneity, particularly for the midline frontal lobe structures where hot spots occur with conventional two-field EBRT. More study needs to be done addressing the clinical implications of optimizing dose uniformity and its effect on long-term cognitive function in selected long-lived patients

Norwegian Oncologists' Expectations of Intensity-modulated Radiotherapy

International Nuclear Information System (INIS)

Muren, Ludvig P.; Mella, Olav; Hafslund, Rune; Dahl, Olav

2002-01-01

Although intensity-modulated radiotherapy (IMRT) may increase the therapeutic ratio of radiotherapy for a range of malignancies, only a few IMRT treatments have yet been performed in the Nordic countries. The scores derived from a national survey to assess Norwegian oncologists' expectations of IMRT are presented. A questionnaire was distributed to all consultants in oncology at Norwegian radiotherapy clinics. Summary scores of daily general radiotherapy workload (DGRTW), acquaintance with IMRT (AI) and expectations of IMRT (EI) were derived. Thirty-nine questionnaires (67%) were returned from a total of 58 oncologists. The oncologists' scores on the AI scale (mean score: 7.5 out of 21) were rather low. Their AI scores were found to be positively correlated with their DGRTW. Higher scores on the EI scale were documented (mean score: 6.2 out of 14): 15 oncologists (39%) rated IMRT as one of the three major contributors to potentially increased cancer survival. Oncologists treating patients with prostate, head and neck, gastrointestinal and CNS tumours had higher EI scores than the other oncologists (7.7 vs. 5.1; p=0.01). The Norwegian radiation oncologists' expectations of IMRT are high in terms of both the potential clinical benefit and the rate of implementation. This should encourage the radiotherapy communities to continue (or rapidly initiate) their efforts in providing the routines required for safe implementation of IMRT

Postoperative radiotherapy for prostate cancer. Morbidity of local-only or local-plus-pelvic radiotherapy

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Waldstein, Cora; Poetter, Richard; Widder, Joachim; Goldner, Gregor [Medical University of Vienna, Department of Radiation Oncology, Comprehensive Cancer Center, General Hospital of Vienna, Vienna (Austria); Doerr, Wolfgang [Medical University of Vienna, Department of Radiation Oncology, Comprehensive Cancer Center, General Hospital of Vienna, Vienna (Austria); Medical University of Vienna, Christian-Doppler Laboratory for Medical Radiation Research for Radiooncology, Vienna (Austria)

2018-01-15

The aim of this work was to characterise actuarial incidence and prevalence of early and late side effects of local versus pelvic three-dimensional conformal postoperative radiotherapy for prostate cancer. Based on a risk-adapted protocol, 575 patients received either local (n = 447) or local-plus-pelvic (n = 128) radiotherapy. Gastrointestinal (GI) and genitourinary (GU) side effects (≥grade 2 RTOG/EORTC criteria) were prospectively assessed. Maximum morbidity, actuarial incidence rate, and prevalence rates were compared between the two groups. For local radiotherapy, median follow-up was 68 months, and the mean dose was 66.7 Gy. In pelvic radiotherapy, the median follow-up was 49 months, and the mean local and pelvic doses were 66.9 and 48.3 Gy respectively. Early GI side effects ≥ G2 were detected in 26% and 42% of patients respectively (p < 0.001). Late GI adverse events were detected in 14% in both groups (p = 0.77). The 5-year actuarial incidence rates were 14% and 14%, while the prevalence rates were 2% and 0% respectively. Early GU ≥ G2 side effects were detected in 15% and 16% (p = 0.96), while late GU morbidity was detected in 18% and 24% (p = 0.001). The 5-year actuarial incidence rates were 16% and 35% (p = 0.001), while the respective prevalence rates were 6% and 8%. Despite the low prevalence of side effects, postoperative pelvic radiotherapy results in significant increases in the actuarial incidence of early GI and late GU morbidity using a conventional 4-field box radiotherapy technique. Advanced treatment techniques like intensity-modulated radiotherapy (IMRT) or volumetric modulated arc radiotherapy (VMAT) should therefore be considered in pelvic radiotherapy to potentially reduce these side effects. (orig.) [German] Ziel der vorgestellten Arbeit ist es, die Haeufigkeit frueher und spaeter Nebenwirkungen nach postoperativer Bestrahlung von Prostatakarzinompatienten zu analysieren. Verglichen wurden dabei die Nebenwirkungen von lokaler

Locoregional control after intensity-modulated radiotherapy for nasopharyngeal carcinoma with an anatomy-based target definition

International Nuclear Information System (INIS)

Kawashima, Mitsuhiko; Ariji, Takaki; Kameoka, Satoru

2013-01-01

The objective of the study was to evaluate locoregional control after intensity-modulated radiotherapy for nasopharyngeal cancer using a target definition along with anatomical boundaries. Forty patients with biopsy-proven squamous cell or non-keratinizing carcinoma of the nasopharynx who underwent intensity-modulated radiotherapy between April 2006 and November 2009 were reviewed. There were 10 females and 30 males with a median age of 48 years (range, 17-74 years). More than half of the patients had T3/4 (n=21) and/or N2/3 (n=24) disease. Intensity-modulated radiotherapy was administered as 70 Gy/33 fractions with or without concomitant chemotherapy. The clinical target volume was contoured along with muscular fascia or periosteum, and the prescribed radiotherapy dose was determined for each anatomical compartment and lymph node level in the head and neck. One local recurrence was observed at Meckel's cave on the periphery of the high-risk clinical target volume receiving a total dose of <63 Gy. Otherwise, six locoregional failures were observed within irradiated volume receiving 70 Gy. Local and nodal control rates at 3 years were 91 and 89%, respectively. Adverse events were acceptable, and 25 (81%) of 31 patients who were alive without recurrence at 2 years had xerostomia of ≤ Grade 1. The overall survival rate at 3 years was 87%. Target definition along with anatomically defined boundaries was feasible without compromise of the therapeutic ratio. It is worth testing this method further to minimize the unnecessary irradiated volume and to standardize the target definition in intensity-modulated radiotherapy for nasopharyngeal cancer. (author)

Intensity modulated conformal radiotherapy

International Nuclear Information System (INIS)

Noel, Georges; Moty-Monnereau, Celine; Meyer, Aurelia; David, Pauline; Pages, Frederique; Muller, Felix; Lee-Robin, Sun Hae; David, Denis Jean

2006-12-01

This publication reports the assessment of intensity-modulated conformal radiotherapy (IMCR). This assessment is based on a literature survey which focussed on indications, efficiency and safety on the short term, on the risk of radio-induced cancer on the long term, on the role in the therapeutic strategy, on the conditions of execution, on the impact on morbidity-mortality and life quality, on the impact on the health system and on public health policies and program. This assessment is also based on the opinion of a group of experts regarding the technical benefit of IMCR, its indications depending on the cancer type, safety in terms of radio-induced cancers, and conditions of execution. Before this assessment, the report thus indicates indications for which the use of IMCR can be considered as sufficient or not determined. It also proposes a technical description of IMCR and helical tomo-therapy, discusses the use of this technique for various pathologies or tumours, analyses the present situation of care in France, and comments the identification of this technique in foreign classifications

Rationale and development of image-guided intensity-modulated radiotherapy post-prostatectomy: the present standard of care?

Directory of Open Access Journals (Sweden)

Murray JR

2015-11-01

Full Text Available Julia R Murray,1,2 Helen A McNair,2 David P Dearnaley1,2 1Academic Urology Unit, Institute of Cancer Research, London, 2Department of Radiotherapy, The Royal Marsden NHS Foundation Trust, Sutton, UK Abstract: The indications for post-prostatectomy radiotherapy have evolved over the last decade, although the optimal timing, dose, and target volume remain to be well defined. The target volume is susceptible to anatomical variations with its borders interfacing with the rectum and bladder. Image-guided intensity-modulated radiotherapy has become the gold standard for radical prostate radiotherapy. Here we review the current evidence for image-guided techniques with intensity-modulated radiotherapy to the prostate bed and describe current strategies to reduce or account for interfraction and intrafraction motion. Keywords: radiotherapy, prostate cancer, post-prostatectomy, image-guided radiation therapy

Factors influencing bowel sparing in intensity modulated whole pelvic radiotherapy for gynaecological malignancies

International Nuclear Information System (INIS)

Georg, Petra; Georg, Dietmar; Hillbrand, Martin; Kirisits, Christian; Poetter, Richard

2006-01-01

Background and purpose: To evaluate the influence of uterus and bladder size on large and small bowel sparing with intensity modulated whole pelvic radiotherapy (IM-WPRT) in gynecologic patients. Patients and methods: Twenty patients were selected; 10 women with cervical cancer treated with definitive radiotherapy (group 'DEF') and 10 endometrial cancer patients treated postoperatively (group 'POST'). Bladder, rectal wall, small (SB) and large bowel (LB) were delineated as organs at risk. A conformal four field technique and a seven field IMRT plan (prescription dose 50.4 Gy) were compared in terms of DVH and various target parameters. Results: At doses between 40 and 50.4 Gy statistically significant improvements (P<0.05) were observed for IM-WPRT for irradiated volume of rectal wall and bladder. In both patient groups, with IMRT the average irradiated volume of SB was reduced by a factor of 6 at 50.4 Gy. This ratio was 2 for LB. In the DEF group the effect of SB-sparing with IMRT correlated with bladder size (correlation coefficient 0.70) while it did not correlate in the postoperative group. The effect of LB-sparing decreased with increasing bladder size in both groups but the impact of IMRT was larger for postoperative patients. Conclusions: IMRT significantly reduced the absolute volume of rectal wall, bladder and bowel irradiated at the prescribed dose level in gynaecologic patients. Main differences between POST and DEF patients receiving IM-WPRT were absolute volumes of LB irradiated to doses between 35 and 50 Gy, suggesting an impact of intact uterus on LB volume in the pelvis. POST patients seem to benefit most from elective nodal IMRT. Bladder filling is an important co-factor influencing the benefit of IMRT with respect to OAR sparing

Dosimetric comparison of three-dimensional conformal and intensity modulated radiotherapy in brain glioma

International Nuclear Information System (INIS)

Lu Jie; Zhang Guifang; Bai Tong; Yin Yong; Fan Tingyong; Wu Chaoxia

2009-01-01

Objective: To investigate the dosimetry advantages of intensity modulated radiotherapy (IMRT)of brain glioma compared with that of three-dimensional conformal radiotherapy (SD CRT). Methods: Ten patients with brain glioma were enrolled in this study. Three-dimensional conf0rmal and intensity modulated radiotherapy plans were performed for each patient. The dose distributions of target volume and normal tissues, conformal index (CI) and heterogeneous index (HI) were analyzed using the dose-volume histogram (DVH). The prescription dose was 60 Gy in 30 fractions. Results: IMRT plans decrease the maximum dose and volume of brainstem, mean dose of affected side parotid and maximum dose of spinal-cord. The CI for PTV of IMRT was superior to that of SD CRT, the HI for PTV has no statistical significance of the two model plans. Conclusions: IMRT plans can obviously decrease the dose and volume of brainstem. IMRT is a potential method in the treatment of brain glioma, and dose escalation was possible in patients with brain glioma. (authors)

Evidence-based review: Quality of life following head and neck intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Scott-Brown, Martin; Miah, Aisha; Harrington, Kevin; Nutting, Chris

2010-01-01

Inverse planned Intensity modulated radiotherapy (IMRT) can minimize the dose to normal structures and therefore can reduce long-term radiotherapy-related morbidity and may improve patients' long-term quality of life. Despite overwhelming evidence that IMRT can reduce late functional deficits in patients with head and neck cancer, treated with radiotherapy, a review of the published literature produced conflicting results with regard to quality of life outcomes. Following a critical appraisal of the literature, reasons for the discrepant outcomes are proposed.

Local failure patterns for patients with nasopharyngeal carcinoma after intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Li, Jia-xin; Huang, Shao-min; Jiang, Xin-hua; Ouyang, Bin; Han, Fei; Liu, Shuai; Wen, Bi-xiu; Lu, Tai-xiang

2014-01-01

To investigate the clinical feature and the local failure patterns after intensity-modulated radiotherapy for nasopharyngeal carcinoma. Between March 2007 and July 2009, 710 patients with nasopharyngeal carcinoma were treated with intensity-modulated radiotherapy. The magnetic resonance imagings obtained at recurrence were registered with the original planning computed tomography for dosimetry analysis. With a median follow-up of 38 months, 34 patients have developed local recurrence (32 cases valid). The incidence of invasion to nasopharynx, parapharyngeal space and the retropharyngeal space by the primary tumors was 100%, 75.0% and 62.5%, respectively, but 78.1%, 34.4% and 21.9% at recurrence, respectively. The rate of invasion to ethmoid sinus was 3.1% by the primary tumors but 28.1% at recurrence (p = 0.005). The topographic analysis of the local failure patterns showed 'central' in 16 patients; 'marginal' in 9; and 'outside' in 7. The median volumes of primary gross tumor were 45.84 cm 3 in the central failure group, 29.44 cm 3 in the marginal failure group, and 21.52 cm 3 in the outside failure group, respectively (p = 0.012), and the median volumes of primary clinical target1 were 87.28 cm 3 , 61.90 cm 3 and 58.74 cm 3 in the three groups, respectively (p = 0.033). In patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy, the recurrent tumors had their unique characteristic and regularity of invasion to adjacent structures. 'Central' failure was the major local failure pattern. The volumes of primary gross tumor and clinical target1 were significantly correlated with recurrent patterns. Employ more aggressive approaches to tumor cells which will be insensitive to radiotherapy may be an effective way to reduce the central failure

Intensity-modulated radiotherapy significantly reduces xerostomia compared with conventional radiotherapy

International Nuclear Information System (INIS)

Braam, Petra M.; Terhaard, Chris H.J. M.D.; Roesink, Judith M.; Raaijmakers, Cornelis P.J.

2006-01-01

Purpose: Xerostomia is a severe complication after radiotherapy for oropharyngeal cancer, as the salivary glands are in close proximity with the primary tumor. Intensity-modulated radiotherapy (IMRT) offers theoretical advantages for normal tissue sparing. A Phase II study was conducted to determine the value of IMRT for salivary output preservation compared with conventional radiotherapy (CRT). Methods and Materials: A total of 56 patients with oropharyngeal cancer were prospectively evaluated. Of these, 30 patients were treated with IMRT and 26 with CRT. Stimulated parotid salivary flow was measured before, 6 weeks, and 6 months after treatment. A complication was defined as a stimulated parotid flow rate <25% of the preradiotherapy flow rate. Results: The mean dose to the parotid glands was 48.1 Gy (SD 14 Gy) for CRT and 33.7 Gy (SD 10 Gy) for IMRT (p < 0.005). The mean parotid flow ratio 6 weeks and 6 months after treatment was respectively 41% and 64% for IMRT and respectively 11% and 18% for CRT. As a result, 6 weeks after treatment, the number of parotid flow complications was significantly lower after IMRT (55%) than after CRT (87%) (p = 0.002). The number of complications 6 months after treatment was 56% for IMRT and 81% for CRT (p = 0.04). Conclusions: IMRT significantly reduces the number of parotid flow complications for patients with oropharyngeal cancer

Dosimetry comparison of irradiation with conformal radiotherapy, intensity modulated radiotherapy, conformal radiotherapy in stereotactic conditions and robotic stereotactic radiotherapy for benign brain tumours

International Nuclear Information System (INIS)

Spasic, E.; Noel, A.; Buchheit, I.; Bernier, V.

2011-01-01

Purpose. - To compare several techniques in order to determine the best treatment for benign brain tumours. Methods and patients. - A retrospective study was performed for five patients who received 3D-conformal radiotherapy, intensity modulated radiotherapy or CyberKnife R . These patients had a meningioma, a pituitary tumour, a cranio-pharyngioma or a neurinoma. In each case, these treatment plans were optimised and compared with the three other dosimetries. Radiobiological or positioning parameters were evaluated, as well as dosimetric parameters, in order to compare treatments with different characteristics. Results. - The dosimetric parameters showed that the choice of treatment seemed to be determined mostly by tumour size, shape and proximity with organs at risk (not tumour localisation). Whereas the results showed no significant deviations with regards to the radiobiological parameters. Therefore, with these parameters, it was difficult to give priority to a treatment. Conclusions. - With regards to benign brain tumours of medium or large size, intensity modulated radiotherapy seemed the recommended treatment. It enabled to obtain a good ratio between efficacy and toxicity for tumours that are really close to organs at risk. Concerning small benign brain tumours, the CyberKnife R was probably the best treatment. (authors)

A comparative study of standard intensity-modulated radiotherapy and RapidArc planning techniques for ipsilateral and bilateral head and neck irradiation

Energy Technology Data Exchange (ETDEWEB)

Pursley, Jennifer, E-mail: jpursley@mgh.harvard.edu [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Damato, Antonio L.; Czerminska, Maria A.; Margalit, Danielle N. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Sher, David J. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States); Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX (United States); Tishler, Roy B. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, MA (United States)

2017-04-01

The purpose of this study was to investigate class solutions using RapidArc volumetric-modulated arc therapy (VMAT) planning for ipsilateral and bilateral head and neck (H&N) irradiation, and to compare dosimetric results with intensity-modulated radiotherapy (IMRT) plans. A total of 14 patients who received ipsilateral and 10 patients who received bilateral head and neck irradiation were retrospectively replanned with several volumetric-modulated arc therapy techniques. For ipsilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the contralateral parotid, two 260° or 270° arcs, and two 210° arcs. For bilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the shoulders, and 3 arcs. All patients had a sliding-window-delivery intensity-modulated radiotherapy plan that was used as the benchmark for dosimetric comparison. For ipsilateral neck irradiation, a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid was dosimetrically comparable to intensity-modulated radiotherapy, with improved conformity (conformity index = 1.22 vs 1.36, p < 0.04) and lower contralateral parotid mean dose (5.6 vs 6.8 Gy, p < 0.03). For bilateral neck irradiation, 3-arc volumetric-modulated arc therapy techniques were dosimetrically comparable to intensity-modulated radiotherapy while also avoiding irradiation through the shoulders. All volumetric-modulated arc therapy techniques required fewer monitor units than sliding-window intensity-modulated radiotherapy to deliver treatment, with an average reduction of 35% for ipsilateral plans and 67% for bilateral plans. Thus, for ipsilateral head and neck irradiation a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid is

Simple Carotid-Sparing Intensity-Modulated Radiotherapy Technique and Preliminary Experience for T1-2 Glottic Cancer

International Nuclear Information System (INIS)

Rosenthal, David I.; Fuller, Clifton D.; Barker, Jerry L.; Mason, Bryan M.S.; Garcia, John A. C.; Lewin, Jan S.; Holsinger, F. Christopher; Stasney, C. Richard; Frank, Steven J.; Schwartz, David L.; Morrison, William H.; Garden, Adam S.; Ang, K. Kian

2010-01-01

Purpose: To investigate the dosimetry and feasibility of carotid-sparing intensity-modulated radiotherapy (IMRT) for early glottic cancer and to report preliminary clinical experience. Methods and Materials: Digital Imaging and Communications in Medicine radiotherapy (DICOM-RT) datasets from 6 T1-2 conventionally treated glottic cancer patients were used to create both conventional IMRT plans. We developed a simplified IMRT planning algorithm with three fields and limited segments. Conventional and IMRT plans were compared using generalized equivalent uniform dose and dose-volume parameters for in-field carotid arteries, target volumes, and organs at risk. We have treated 11 patients with this simplified IMRT technique. Results: Intensity-modulated radiotherapy consistently reduced radiation dose to the carotid arteries (p < 0.05) while maintaining the clinical target volume coverage. With conventional planning, median carotid V35, V50, and V63 were 100%, 100%, and 69.0%, respectively. With IMRT planning these decreased to 2%, 0%, and 0%, respectively (p < 0.01). Radiation planning and treatment times were similar for conventional radiotherapy and IMRT. Treatment results have been excellent thus far. Conclusions: Intensity-modulated radiotherapy significantly reduced unnecessary radiation dose to the carotid arteries compared with conventional lateral fields while maintaining clinical target volume coverage. Further experience and longer follow-up will be required to demonstrate outcomes for cancer control and carotid artery effects.

[Positioning errors of CT common rail technique in intensity-modulated radiotherapy for nasopharyngeal carcinoma].

Science.gov (United States)

Tian, Fei; Xu, Zihai; Mo, Li; Zhu, Chaohua; Chen, Chaomin

2012-11-01

To evaluate the value of CT common rail technique for application in intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC). Twenty-seven NPC patients underwent Somatom CT scans using the Siemens CTVision system prior to the commencement of the radiotherapy sessions. The acquired CT images were registered with the planning CT images using the matching function of the system to obtain the linear set-up errors of 3 directions, namely X (left to right), Y (superior to inferior), and Z (anterior to posterior). The errors were then corrected online on the moving couch. The 27 NPC patients underwent a total of 110 CT scans and the displacement deviations of the X, Y and Z directions were -0.16∓1.68 mm, 0.25∓1.66 mm, and 0.33∓1.09 mm, respectively. CT common rail technique can accurately and rapidly measure the space error between the posture and the target area to improve the set-up precision of intensity-modulated radiotherapy for NPC.

Long-term decision regret after post-prostatectomy image-guided intensity-modulated radiotherapy.

Science.gov (United States)

Shakespeare, Thomas P; Chin, Stephen; Manuel, Lucy; Wen, Shelly; Hoffman, Matthew; Wilcox, Shea W; Aherne, Noel J

2017-02-01

Decision regret (DR) may occur when a patient believes their outcome would have been better if they had decided differently about their management. Although some studies investigate DR after treatment for localised prostate cancer, none report DR in patients undergoing surgery and post-prostatectomy radiotherapy. We evaluated DR in this group of patients overall, and for specific components of therapy. We surveyed 83 patients, with minimum 5 years follow-up, treated with radical prostatectomy (RP) and post-prostatectomy image-guided intensity-modulated radiotherapy (IG-IMRT) to 64-66 Gy following www.EviQ.org.au protocols. A validated questionnaire identified DR if men either indicated that they would have been better off had they chosen another treatment, or they wished they could change their mind about treatment. There was an 85.5% response rate, with median follow-up post-IMRT 78 months. Adjuvant IG-IMRT was used in 28% of patients, salvage in 72% and ADT in 48%. A total of 70% of patients remained disease-free. Overall, 16.9% of patients expressed DR for treatment, with fourfold more regret for the RP component of treatment compared to radiotherapy (16.9% vs 4.2%, P = 0.01). DR for androgen deprivation was 14.3%. Patients were regretful of surgery due to toxicity, not being adequately informed about radiotherapy as an alternative, positive margins and surgery costs (83%, 33%, 25% and 8% of regretful patients respectively). Toxicity caused DR in the three radiotherapy-regretful and four ADT-regretful patients. Patients were twice as regretful overall, and of surgery, for salvage vs adjuvant approaches (both 19.6% vs 10.0%). Decision regret after RP and post-prostatectomy IG-IMRT is uncommon, although patients regret RP more than post-operative IG-IMRT. This should reassure urologists referring patients for post-prostatectomy IG-IMRT, particularly in the immediate adjuvant setting. Other implications include appropriate patient selection for RP (and

Development of a quality control system in intensity modulated radiotherapy (IMRT)

International Nuclear Information System (INIS)

Souza, Roberto Salomon de; Braz, Delson

2013-01-01

The more complex the technique of radiotherapy is, the more refined the quality control must be. The technique of Intensity Modulated Radiotherapy (IMRT) is one of the technological innovations that gained space in the whole worlds in the last decade whose parameters of quality control are not fully established yet. The present work developed a phantom for quality control in IMRT to be implemented in the routine of the Radiotherapy Quality Control Program (PQRT) of the Brazilian National Cancer Institute (INCa). The device consists of a block formed by several polystyrene slice with TDLs and radiochromic film inserted. It should be sent (or taken) to the Program participating institutions to be irradiated under certain conditions and then be returned to the PQRT., where the discrepancy degree between the planned treatment and those effectively delivered will be evaluated. The system was validated through the test cases and the pilot program preformed in nine radiotherapy centers that perform IMRT in the southeast region of Brazil. (author)

Travelling for treatment; does distance and deprivation affect travel for intensity-modulated radiotherapy in the rural setting for head and neck cancer?

Science.gov (United States)

Cosway, B; Douglas, L; Armstrong, N; Robson, A

2017-06-01

NHS England has commissioned intensity-modulated radiotherapy for head and neck cancers from Newcastle hospitals for patients in North Cumbria. This study assessed whether travel distances affected the decision to travel to Newcastle (to receive intensity-modulated radiotherapy) or Carlisle (to receive conformal radiotherapy). All patients for whom the multidisciplinary team recommended intensity-modulated radiotherapy between December 2013 and January 2016 were included. Index of multiple deprivation scores and travel distances were calculated. Patients were also asked why they chose their treating centre. Sixty-nine patients were included in this study. There were no significant differences in travel distance (p = 0.53) or index of multiple deprivation scores (p = 0.47) between patients opting for treatment in Carlisle or Newcastle. However, 29 of the 33 patients gave travel distance as their main reason for not travelling for treatment. Quantitatively, travel distance and deprivation does not impact on whether patients accept intensity-modulated radiotherapy. However, patients say distance is a major barrier for access. Future research should explore how to reduce this.

Chemotherapy and intensity modulated conformational radiotherapy for locally advanced pancreas cancers

International Nuclear Information System (INIS)

Huguet, F.; Wu, A.; Zhang, Z.; Winston, C.; Reidy, D.; Ho, A.; Allen, P.; Karyn, G.

2011-01-01

The authors report a retrospective study of the tolerance and survival of 48 patients who have been treated by a chemotherapy followed by a chemotherapy concomitant with an intensity-modulated radiotherapy for a locally advanced pancreas cancer. Results are discussed in terms of toxicity, cancer response, operability, survival rate. Tolerance is good. Local control rates, global survival rates and secondary resection rates are promising. Short communication

Dosimetric study of volumetric arc modulation with RapidArc and intensity-modulated radiotherapy in patients with cervical cancer and comparison with 3-dimensional conformal technique for definitive radiotherapy in patients with cervical cancer

Energy Technology Data Exchange (ETDEWEB)

Guy, Jean-Baptiste [Department of Radiation Oncology, Institut de Cancérologie de la Loire Lucien Neuwirth, Saint-Priest en Jarez (France); Falk, Alexander T. [Department of Radiation Oncology, Centre Antoine Lacassagne, Nice (France); Auberdiac, Pierre [Department of Radiation Oncology, Clinique Claude Bernard, Albi (France); Cartier, Lysian; Vallard, Alexis [Department of Radiation Oncology, Institut de Cancérologie de la Loire Lucien Neuwirth, Saint-Priest en Jarez (France); Ollier, Edouard [Department of Pharmacology-Toxicology, Centre Hospitalier Universitaire de Saint-Etienne, Saint-Priest en Jarez (France); Trone, Jane-Chloé; Khodri, Moustapha [Department of Radiation Oncology, Institut de Cancérologie de la Loire Lucien Neuwirth, Saint-Priest en Jarez (France); Chargari, Cyrus [Department of Radiation Oncology, Hôpital d’instruction de Armées du Val-de-Grâce, Paris (France); Magné, Nicolas, E-mail: nicolas.magne@icloire.fr [Department of Radiation Oncology, Institut de Cancérologie de la Loire Lucien Neuwirth, Saint-Priest en Jarez (France)

2016-04-01

Introduction: For patients with cervical cancer, intensity-modulated radiation therapy (IMRT) improves target coverage and allows dose escalation while reducing the radiation dose to organs at risk (OARs). In this study, we compared dosimetric parameters among 3-dimensional conformal radiotherapy (3D-CRT), “step-and-shoot” IMRT, and volumetric intensity-modulated arc radiotherapy (VMAT) in a series of patients with cervical cancer receiving definitive radiotherapy. Computed tomography (CT) scans of 10 patients with histologically proven cervical cancer treated with definitive radiation therapy (RT) from December 2008 to March 2010 at our department were selected for this study. The gross tumor volume (GTV) and clinical target volume (CTV) were delineated following the guidelines of the Gyn IMRT consortium that included cervix, uterus, parametrial tissues, and the pelvic nodes including presacral. The median age was 57 years (range: 30 to 85 years). All 10 patients had squamous cell carcinoma with Federation of Gynecology and Obstetrics (FIGO) stage IB-IIIB. All patients were treated by VMAT. OAR doses were significantly reduced for plans with intensity-modulated technique compared with 3D-CRT except for the dose to the vagina. Between the 2 intensity-modulated techniques, significant difference was observed for the mean dose to the small intestine, to the benefit of VMAT (p < 0.001). There was no improvement in terms of OARs sparing for VMAT although there was a tendency for a slightly decreased average dose to the rectum: − 0.65 Gy but not significant (p = 0.07). The intensity modulation techniques have many advantages in terms of quality indexes, and particularly OAR sparing, compared with 3D-CRT. Following the ongoing technologic developments in modern radiotherapy, it is essential to evaluate the intensity-modulated techniques on prospective studies of a larger scale.

Intensity-Modulated Whole Abdominal Radiotherapy After Surgery and Carboplatin/Taxane Chemotherapy for Advanced Ovarian Cancer: Phase I Study

International Nuclear Information System (INIS)

Rochet, Nathalie; Sterzing, Florian; Jensen, Alexandra D.; Dinkel, Julien; Herfarth, Klaus K.; Schubert, Kai; Eichbaum, Michael H.; Schneeweiss, Andreas; Sohn, Christof; Debus, Juergen; Harms, Wolfgang

2010-01-01

Purpose: To assess the feasibility and toxicity of consolidative intensity-modulated whole abdominal radiotherapy (WAR) after surgery and chemotherapy in high-risk patients with advanced ovarian cancer. Methods and Materials: Ten patients with optimally debulked ovarian cancer International Federation of Gynecology and Obstetrics Stage IIIc were treated in a Phase I study with intensity-modulated WAR up to a total dose of 30 Gy in 1.5-Gy fractions as consolidation therapy after adjuvant carboplatin/taxane chemotherapy. Treatment was delivered using intensity-modulated radiotherapy in a step-and-shoot technique (n = 3) or a helical tomotherapy technique (n = 7). The planning target volume included the entire peritoneal cavity and the pelvic and para-aortal node regions. Organs at risk were kidneys, liver, heart, vertebral bodies, and pelvic bones. Results: Intensity-modulated WAR resulted in an excellent coverage of the planning target volume and an effective sparing of the organs at risk. The treatment was well tolerated, and no severe Grade 4 acute side effects occurred. Common Toxicity Criteria Grade III toxicities were as follows: diarrhea (n = 1), thrombocytopenia (n = 1), and leukopenia (n = 3). Radiotherapy could be completed by all the patients without any toxicity-related interruption. Median follow-up was 23 months, and 4 patients had tumor recurrence (intraperitoneal progression, n = 3; hepatic metastasis, n = 1). Small bowel obstruction caused by adhesions occurred in 3 patients. Conclusions: The results of this Phase I study showed for the first time, to our knowledge, the clinical feasibility of intensity-modulated whole abdominal radiotherapy, which could offer a new therapeutic option for consolidation treatment of advanced ovarian carcinoma after adjuvant chemotherapy in selected subgroups of patients. We initiated a Phase II study to further evaluate the toxicity of this intensive multimodal treatment.

Intensity-modulated whole abdominal radiotherapy after surgery and carboplatin/taxane chemotherapy for advanced ovarian cancer: phase I study.

Science.gov (United States)

Rochet, Nathalie; Sterzing, Florian; Jensen, Alexandra D; Dinkel, Julien; Herfarth, Klaus K; Schubert, Kai; Eichbaum, Michael H; Schneeweiss, Andreas; Sohn, Christof; Debus, Juergen; Harms, Wolfgang

2010-04-01

To assess the feasibility and toxicity of consolidative intensity-modulated whole abdominal radiotherapy (WAR) after surgery and chemotherapy in high-risk patients with advanced ovarian cancer. Ten patients with optimally debulked ovarian cancer International Federation of Gynecology and Obstetrics Stage IIIc were treated in a Phase I study with intensity-modulated WAR up to a total dose of 30 Gy in 1.5-Gy fractions as consolidation therapy after adjuvant carboplatin/taxane chemotherapy. Treatment was delivered using intensity-modulated radiotherapy in a step-and-shoot technique (n = 3) or a helical tomotherapy technique (n = 7). The planning target volume included the entire peritoneal cavity and the pelvic and para-aortal node regions. Organs at risk were kidneys, liver, heart, vertebral bodies, and pelvic bones. Intensity-modulated WAR resulted in an excellent coverage of the planning target volume and an effective sparing of the organs at risk. The treatment was well tolerated, and no severe Grade 4 acute side effects occurred. Common Toxicity Criteria Grade III toxicities were as follows: diarrhea (n = 1), thrombocytopenia (n = 1), and leukopenia (n = 3). Radiotherapy could be completed by all the patients without any toxicity-related interruption. Median follow-up was 23 months, and 4 patients had tumor recurrence (intraperitoneal progression, n = 3; hepatic metastasis, n = 1). Small bowel obstruction caused by adhesions occurred in 3 patients. The results of this Phase I study showed for the first time, to our knowledge, the clinical feasibility of intensity-modulated whole abdominal radiotherapy, which could offer a new therapeutic option for consolidation treatment of advanced ovarian carcinoma after adjuvant chemotherapy in selected subgroups of patients. We initiated a Phase II study to further evaluate the toxicity of this intensive multimodal treatment.

Reduced Acute Bowel Toxicity in Patients Treated With Intensity-Modulated Radiotherapy for Rectal Cancer

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Samuelian, Jason M. [Department of Radiation Oncology, Mayo Clinic, Scottsdale, AZ (United States); Callister, Matthew D., E-mail: Callister.matthew@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Scottsdale, AZ (United States); Ashman, Jonathan B. [Department of Radiation Oncology, Mayo Clinic, Scottsdale, AZ (United States); Young-Fadok, Tonia M. [Division of Colorectal Surgery, Mayo Clinic, Scottsdale, AZ (United States); Borad, Mitesh J. [Division of Hematology-Oncology, Mayo Clinic, Scottsdale, AZ (United States); Gunderson, Leonard L. [Department of Radiation Oncology, Mayo Clinic, Scottsdale, AZ (United States)

2012-04-01

Purpose: We have previously shown that intensity-modulated radiotherapy (IMRT) can reduce dose to small bowel, bladder, and bone marrow compared with three-field conventional radiotherapy (CRT) technique in the treatment of rectal cancer. The purpose of this study was to review our experience using IMRT to treat rectal cancer and report patient clinical outcomes. Methods and Materials: A retrospective review was conducted of patients with rectal cancer who were treated at Mayo Clinic Arizona with pelvic radiotherapy (RT). Data regarding patient and tumor characteristics, treatment, acute toxicity according to the Common Terminology Criteria for Adverse Events v 3.0, tumor response, and perioperative morbidity were collected. Results: From 2004 to August 2009, 92 consecutive patients were treated. Sixty-one (66%) patients were treated with CRT, and 31 (34%) patients were treated with IMRT. All but 2 patients received concurrent chemotherapy. There was no significant difference in median dose (50.4 Gy, CRT; 50 Gy, IMRT), preoperative vs. postoperative treatment, type of concurrent chemotherapy, or history of previous pelvic RT between the CRT and IMRT patient groups. Patients who received IMRT had significantly less gastrointestinal (GI) toxicity. Sixty-two percent of patients undergoing CRT experienced {>=}Grade 2 acute GI side effects, compared with 32% among IMRT patients (p = 0.006). The reduction in overall GI toxicity was attributable to fewer symptoms from the lower GI tract. Among CRT patients, {>=}Grade 2 diarrhea and enteritis was experienced among 48% and 30% of patients, respectively, compared with 23% (p = 0.02) and 10% (p = 0.015) among IMRT patients. There was no significant difference in hematologic or genitourinary acute toxicity between groups. In addition, pathologic complete response rates and postoperative morbidity between treatment groups did not differ significantly. Conclusions: In the management of rectal cancer, IMRT is associated with a

Reduced Acute Bowel Toxicity in Patients Treated With Intensity-Modulated Radiotherapy for Rectal Cancer

International Nuclear Information System (INIS)

Samuelian, Jason M.; Callister, Matthew D.; Ashman, Jonathan B.; Young-Fadok, Tonia M.; Borad, Mitesh J.; Gunderson, Leonard L.

2012-01-01

Purpose: We have previously shown that intensity-modulated radiotherapy (IMRT) can reduce dose to small bowel, bladder, and bone marrow compared with three-field conventional radiotherapy (CRT) technique in the treatment of rectal cancer. The purpose of this study was to review our experience using IMRT to treat rectal cancer and report patient clinical outcomes. Methods and Materials: A retrospective review was conducted of patients with rectal cancer who were treated at Mayo Clinic Arizona with pelvic radiotherapy (RT). Data regarding patient and tumor characteristics, treatment, acute toxicity according to the Common Terminology Criteria for Adverse Events v 3.0, tumor response, and perioperative morbidity were collected. Results: From 2004 to August 2009, 92 consecutive patients were treated. Sixty-one (66%) patients were treated with CRT, and 31 (34%) patients were treated with IMRT. All but 2 patients received concurrent chemotherapy. There was no significant difference in median dose (50.4 Gy, CRT; 50 Gy, IMRT), preoperative vs. postoperative treatment, type of concurrent chemotherapy, or history of previous pelvic RT between the CRT and IMRT patient groups. Patients who received IMRT had significantly less gastrointestinal (GI) toxicity. Sixty-two percent of patients undergoing CRT experienced ≥Grade 2 acute GI side effects, compared with 32% among IMRT patients (p = 0.006). The reduction in overall GI toxicity was attributable to fewer symptoms from the lower GI tract. Among CRT patients, ≥Grade 2 diarrhea and enteritis was experienced among 48% and 30% of patients, respectively, compared with 23% (p = 0.02) and 10% (p = 0.015) among IMRT patients. There was no significant difference in hematologic or genitourinary acute toxicity between groups. In addition, pathologic complete response rates and postoperative morbidity between treatment groups did not differ significantly. Conclusions: In the management of rectal cancer, IMRT is associated with a

Anal wall sparing effect of an endorectal balloon in 3D conformal and intensity-modulated prostate radiotherapy.

NARCIS (Netherlands)

Smeenk, R.J.; Lin, E.N.J.T. van; Kollenburg, P. van; Kunze-Busch, M.C.; Kaanders, J.H.A.M.

2009-01-01

BACKGROUND AND PURPOSE: To investigate the anal wall (Awall) sparing effect of an endorectal balloon (ERB) in 3D conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for prostate cancer. MATERIALS AND METHODS: In 24 patients with localized prostate carcinoma, two planning

Benchmarking Dosimetric Quality Assessment of Prostate Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Senthi, Sashendra; Gill, Suki S.; Haworth, Annette; Kron, Tomas; Cramb, Jim; Rolfo, Aldo; Thomas, Jessica; Duchesne, Gillian M.; Hamilton, Christopher H.; Joon, Daryl Lim; Bowden, Patrick; Foroudi, Farshad

2012-01-01

Purpose: To benchmark the dosimetric quality assessment of prostate intensity-modulated radiotherapy and determine whether the quality is influenced by disease or treatment factors. Patients and Methods: We retrospectively analyzed the data from 155 consecutive men treated radically for prostate cancer using intensity-modulated radiotherapy to 78 Gy between January 2007 and March 2009 across six radiotherapy treatment centers. The plan quality was determined by the measures of coverage, homogeneity, and conformity. Tumor coverage was measured using the planning target volume (PTV) receiving 95% and 100% of the prescribed dose (V 95% and V 100% , respectively) and the clinical target volume (CTV) receiving 95% and 100% of the prescribed dose. Homogeneity was measured using the sigma index of the PTV and CTV. Conformity was measured using the lesion coverage factor, healthy tissue conformity index, and the conformity number. Multivariate regression models were created to determine the relationship between these and T stage, risk status, androgen deprivation therapy use, treatment center, planning system, and treatment date. Results: The largest discriminatory measurements of coverage, homogeneity, and conformity were the PTV V 95% , PTV sigma index, and conformity number. The mean PTV V 95% was 92.5% (95% confidence interval, 91.3–93.7%). The mean PTV sigma index was 2.10 Gy (95% confidence interval, 1.90–2.20). The mean conformity number was 0.78 (95% confidence interval, 0.76–0.79). The treatment center independently influenced the coverage, homogeneity, and conformity (all p 95% only, with it being better at the start (p = .013). Risk status, T stage, and the use of androgen deprivation therapy did not influence any aspect of plan quality. Conclusion: Our study has benchmarked measures of coverage, homogeneity, and conformity for the treatment of prostate cancer using IMRT. The differences seen between centers and planning systems and the coverage

A Comparison of Helical Intensity-Modulated Radiotherapy, Intensity-Modulated Radiotherapy, and 3D-Conformal Radiation Therapy for Pancreatic Cancer

International Nuclear Information System (INIS)

Poppe, Matthew M.; Narra, Venkat; Yue, Ning J.; Zhou Jinghao; Nelson, Carl; Jabbour, Salma K.

2011-01-01

We assessed dosimetric differences in pancreatic cancer radiotherapy via helical intensity-modulated radiotherapy (HIMRT), linac-based IMRT, and 3D-conformal radiation therapy (3D-CRT) with regard to successful plan acceptance and dose to critical organs. Dosimetric analysis was performed in 16 pancreatic cases that were planned to 54 Gy; both post-pancreaticoduodenectomy (n = 8) and unresected (n = 8) cases were compared. Without volume modification, plans met constraints 75% of the time with HIMRT and IMRT and 13% with 3D-CRT. There was no statistically significantly improvement with HIMRT over conventional IMRT in reducing liver V35, stomach V45, or bowel V45. HIMRT offers improved planning target volume (PTV) dose homogeneity compared with IMRT, averaging a lower maximum dose and higher volume receiving the prescription dose (D100). HIMRT showed an increased mean dose over IMRT to bowel and liver. Both HIMRT and IMRT offer a statistically significant improvement over 3D-CRT in lowering dose to liver, stomach, and bowel. The results were similar for both unresected and resected patients. In pancreatic cancer, HIMRT offers improved dose homogeneity over conventional IMRT and several significant benefits to 3D-CRT. Factors to consider before incorporating IMRT into pancreatic cancer therapy are respiratory motion, dose inhomogeneity, and mean dose.

Intensity-modulated radiotherapy for cancers in childhood

International Nuclear Information System (INIS)

Leseur, J.; Le Prise, E.; Leseur, J.; Carrie, C.; Beneyton, V.; Bernier, V.; Beneyton, V.; Mahee, M.A.; Supiot, S.

2009-01-01

Approximately 40-50% of children with cancer will be irradiated during their treatment. Intensity-modulated radiotherapy (I.M.R.T.) by linear accelerator or helical tomo-therapy improves dose distribution in target volumes and normal tissue sparing. This technology could be particularly useful for pediatric patients to achieve an optimal dose distribution in complex volumes close to critical structures. The use of I.M.R.T. can increase the volume of tissue receiving low-dose radiation, and consequently carcinogenicity in childhood population with a good overall survival and long period of life expectancy. This review will present the current and potential I.M.R.T. indications for cancers in childhood, and discuss the benefits and problems of this technology aiming to define recommendations in the use of I.M.R.T. and specific doses constraints in Pediatrics. (authors)

Magnetic resonance sialography for investigating major salivary gland duct system after intensity-modulated radiotherapy of nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Ou Dan; He Xiayun; Zhang Yunyan

2013-01-01

We investigated the value of magnetic resonance sialography for evaluating xerostomia induced by intensity-modulated radiotherapy for nasopharyngeal carcinoma. Fourteen patients with nasopharyngeal carcinoma were treated with intensity-modulated radiotherapy. Salivary function was assessed by magnetic resonance sialography and subjective evaluation criteria pre-treatment, 1 week and 1 year post-radiotherapy. A magnetic resonance sialography categorical scoring system was used to compare the visibility of salivary ducts. The average mean dose was 38.93 Gy to the parotid glands and 59.34 Gy to the submandibular glands. Before radiotherapy, the visibility scores of both the parotid and submandibular ducts increased after secretion stimulation. The scores decreased and the response to stimulation was attenuated 1 week post-radiotherapy. For most of the parotid ducts, the visibility score improved at 1 year post-radiotherapy both at rest and under stimulation, but not for the submandibular ducts. With a median follow-up of 12.3 months, 8/12 patients had grade 1 xerostomia and 4/12 had grade 2 xerostomia. Magnetic resonance sialography allows non-invasive evaluation of radiation-induced ductal changes in the major salivary glands and enables reliable prediction of radiation-induced xerostomia. (author)

Sparing functional anatomical structures during intensity-modulated radiotherapy: an old problem, a new solution.

Science.gov (United States)

Tan, Wenyong; Han, Guang; Wei, Shaozhong; Hu, Desheng

2014-08-01

During intensity-modulated radiotherapy, an organ is usually assumed to be functionally homogeneous and, generally, its anatomical and spatial heterogeneity with respect to radiation response are not taken into consideration. However, advances in imaging and radiation techniques as well as an improved understanding of the radiobiological response of organs have raised the possibility of sparing the critical functional structures within various organs at risk during intensity-modulated radiotherapy. Here, we discuss these structures, which include the critical brain structure, or neural nuclei, and the nerve fiber tracts in the CNS, head and neck structures related to radiation-induced salivary and swallowing dysfunction, and functional structures in the heart and lung. We suggest that these structures can be used as potential surrogate organs at risk in order to minimize their radiation dose and/or irradiated volume without compromising the dose coverage of the target volume during radiation treatment.

Chest wall desmoid tumours treated with definitive radiotherapy: a plan comparison of 3D conformal radiotherapy, intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy

International Nuclear Information System (INIS)

Liu, Jia; Ng, Diana; Lee, James; Stalley, Paul; Hong, Angela

2016-01-01

Definitive radiotherapy is often used for chest wall desmoid tumours due to size or anatomical location. The delivery of radiotherapy is challenging due to the large size and constraints of normal surrounding structures. We compared the dosimetry of 3D conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc radiotherapy (VMAT) to evaluate the best treatment option. Ten consecutive patients with inoperable chest wall desmoid tumours (PTV range 416–4549 cm 3 ) were selected. For each patient, 3DCRT, IMRT and VMAT plans were generated and the Conformity Index (CI), organ at risk (OAR) doses and monitor unit (MU) were evaluated. The Wilcoxon signed-rank test was used to compare dose delivered to both target and OARs. The mean number of fields for 3DCRT and IMRT were 6.3 ± 2.1, 7.2 ± 1.8. The mean number of arcs for VMAT was 3.7 ± 1.1. The mean conformity index of VMAT (0.98 ± 0.14) was similar to that of IMRT (1.03 ± 0.13), both of which were significantly better than 3DCRT (1.35 ± 0.20; p = 0.005). The mean dose to lung was significantly higher for 3DCRT (11.9Gy ± 7.9) compared to IMRT (9.4Gy ± 5.4, p = 0.014) and VMAT (8.9Gy ± 4.5, p = 0.017). For the 3 females, the low dose regions in the ipsilateral breast for VMAT were generally less with VMAT. IMRT plans required 1427 ± 532 MU per fraction which was almost 4-fold higher than 3DCRT (313 ± 112, P = 0.005). Compared to IMRT, VMAT plans required 60 % less MU (570 ± 285, P = 0.005). For inoperable chest wall desmoid tumours, VMAT delivered equivalent target coverage when compared to IMRT but required 60 % less MU. Both VMAT and IMRT were superior to 3DCRT in terms of better PTV coverage and sparing of lung tissue

Early versus delayed postoperative radiotherapy for treatment of low-grade gliomas

Science.gov (United States)

Sarmiento, J Manuel; Venteicher, Andrew S; Patil, Chirag G

2015-01-01

Background In most people with low-grade gliomas (LGG), the primary treatment regimen remains a combination of surgery followed by postoperative radiotherapy. However, the optimal timing of radiotherapy is controversial. It is unclear whether to use radiotherapy in the early postoperative period, or whether radiotherapy should be delayed until tumour progression occurs. Objectives To assess the effects of early postoperative radiotherapy versus radiotherapy delayed until tumour progression for low-grade intracranial gliomas in people who had initial biopsy or surgical resection. Search methods We searched up to September 2014 the following electronic databases: the Cochrane Register of Controlled Trials (CENTRAL, Issue 8, 2014), MEDLINE (1948 to Aug week 3, 2014), and EMBASE (1980 to Aug week 3, 2014) to identify trials for inclusion in this Cochrane review. Selection criteria We included randomised controlled trials (RCTs) that compared early versus delayed radiotherapy following biopsy or surgical resection for the treatment of people with newly diagnosed intracranial LGG (astrocytoma, oligodendroglioma, mixed oligoastrocytoma, astroblastoma, xanthoastrocytoma, or ganglioglioma). Radiotherapy may include conformal external beam radiotherapy (EBRT) with linear accelerator or cobalt-60 sources, intensity-modulated radiotherapy (IMRT), or stereotactic radiosurgery (SRS). Data collection and analysis Three review authors independently assessed the trials for inclusion and risk of bias, and extracted study data. We resolved any differences between review authors by discussion. Adverse effects were also extracted from the study report. We performed meta-analyses using a random-effects model with inverse variance weighting. Main results We included one large, multi-institutional, prospective RCT, involving 311 participants; the risk of bias in this study was unclear. This study found that early postoperative radiotherapy is associated with an increase in time to

Radiation-Induced Cancers From Modern Radiotherapy Techniques: Intensity-Modulated Radiotherapy Versus Proton Therapy

International Nuclear Information System (INIS)

Yoon, Myonggeun; Ahn, Sung Hwan; Kim, Jinsung; Shin, Dong Ho; Park, Sung Yong; Lee, Se Byeong; Shin, Kyung Hwan; Cho, Kwan Ho

2010-01-01

Purpose: To assess and compare secondary cancer risk resulting from intensity-modulated radiotherapy (IMRT) and proton therapy in patients with prostate and head-and-neck cancer. Methods and Materials: Intensity-modulated radiotherapy and proton therapy in the scattering mode were planned for 5 prostate caner patients and 5 head-and-neck cancer patients. The secondary doses during irradiation were measured using ion chamber and CR-39 detectors for IMRT and proton therapy, respectively. Organ-specific radiation-induced cancer risk was estimated by applying organ equivalent dose to dose distributions. Results: The average secondary doses of proton therapy for prostate cancer patients, measured 20-60cm from the isocenter, ranged from 0.4 mSv/Gy to 0.1 mSv/Gy. The average secondary doses of IMRT for prostate patients, however, ranged between 3 mSv/Gy and 1 mSv/Gy, approximately one order of magnitude higher than for proton therapy. Although the average secondary doses of IMRT were higher than those of proton therapy for head-and-neck cancers, these differences were not significant. Organ equivalent dose calculations showed that, for prostate cancer patients, the risk of secondary cancers in out-of-field organs, such as the stomach, lungs, and thyroid, was at least 5 times higher for IMRT than for proton therapy, whereas the difference was lower for head-and-neck cancer patients. Conclusions: Comparisons of organ-specific organ equivalent dose showed that the estimated secondary cancer risk using scattering mode in proton therapy is either significantly lower than the cases in IMRT treatment or, at least, does not exceed the risk induced by conventional IMRT treatment.

Cervix carcinomas: place of intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Barillot, I.

2009-01-01

While indications of modulated intensity radiation therapy (I.M.R.T.) are perfectly defined in head and neck and prostate cancer patients, this technique remains under evaluation for gynecologic tumours. The implementation of conformal three dimensional radiotherapy in the late 1990 has been the first important step for optimisation of treatment of cervix carcinomas, as it permitted a better target coverage with a significant reduction of the bladder dose. However, this technique often leads to an irradiation of a larger volume of rectum in locally advanced stages and could only spare a limited amount of intestine. I.R.M.T. is one of the optimisation methods potentially efficient for a better sparing of digestive tract during irradiation of cervix carcinomas. The aim of this literature review is to provide the arguments supporting this hypothesis, and to define the place of this technique for dose escalation. (authors)

Minimising contralateral breast dose in post-mastectomy intensity-modulated radiotherapy by incorporating conformal electron irradiation

NARCIS (Netherlands)

van der Laan, Hans Paul; Korevaar, Erik W; Dolsma, Willemtje; Maduro, John H; Langendijk, Johannes A

PURPOSE: To assess the potential benefit of incorporating conformal electron irradiation in intensity-modulated radiotherapy (IMRT) for loco-regional post-mastectomy RT. PATIENTS AND METHODS: Ten consecutive patients that underwent left-sided mastectomy were selected for this comparative planning

Therapeutic Results of Radiotherapy in Rectal Carcinoma -Comparison of Sandwich Technique Radiotherapy with Postoperative Radiotherapy

International Nuclear Information System (INIS)

Huh, Gil Cha; Suh, Hyun Suk; Lee, Hyuk Sang; Kim, Re Hwe; Kim, Chul Soo; Kim, Hong Yong; Kim, Sung Rok

1996-01-01

Purpose : To evaluate the potential advantage for 'sandwich' technique radiotherapy compared to postoperative radiotherapy in respectable rectal cancer. Between January 1989 and May 1994, 60 patients with respectable rectal cancer were treated at Inje University Seoul and Sanggye Paik Hospital.Fifty one patients were available for analysis : 20 patients were treated with sandwich technique radiotherapy and 31 patients were treated with postoperative radiotherapy. In sandwich technique radiotherapy(RT), patients were treated with preoperative RT 1500 cGy/5fx followed by immediate curative resection. Patients staged as Astler-Coller B2, C were considered for postoperative RT with 2500-4500 cGy. In postoperative RT, total radiation dose of 4500-6120 cGy, 180 cGy daily at 4-6 weeks was delivered. Patients were followed for median period of 25 months. Results : The overall 5-year survival rates for sandwich technique RT group and postoperative RT group were 60% and 71%, respectively(p>0.05). The 5-year disease free survival rates for each group were 63%. There was no difference in local failure rate between two groups(11% versus 7%). Incidence of distant metastasis was 11%(2/20) in the sandwich technique RT group and 20%(6/31) in the postoperative RT group(p>0.05). The frequencies of acute and chronic complications were comparable in both groups. Conclusion : The sandwich technique radiotherapy group shows local recurrence and survival similar to those of postoperative RT alone group but reduced distant metastasis compared to postoperative RT group. But long term follow-up and large number of patients is needed to make an any firm conclusion regarding the value of this sandwich technique RT

The incidence of postoperative radiotherapy-induced acute dermatitis in breast cancer and its influencing factors for Chinese women

Directory of Open Access Journals (Sweden)

Ding J

2018-03-01

Full Text Available Jingxian Ding,1,2,* Yonghong Guo,3,* Qingge Li,1 Jun Chen,4 Pinghua Hu,4 Qiuming Liu,4 Yali Cao,4 Jiong Wu5,6 1Department of Radiation Oncology, The Third Hospital of Nanchang, Nanchang, China; 2Department of Oncology, Fudan University Shanghai Cancer Center, Shanghai, China; 3Department of Radiation Oncology, The Fourth Affiliated Hospital of Nanchang University, Nanchang, China; 4Department of Breast Surgery, The Third Hospital of Nanchang, Nanchang, China; 5Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai, China; 6Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China *These authors contributed equally to this work Purpose: To investigate the incidence of skin acute reaction and its influencing factors in postoperative breast cancer radiotherapy patients. Methods: One hundred and seventy three cases of breast cancer patients treated with postoperative radiotherapy were consecutively enrolled from June 1, 2016 to July 31, 2017 in our breast cancer center. Irradiation technology includes conformal intensity-modulated radiotherapy and a conventional two-dimensional one with conventional fraction. Any acute radiation dermatitis was recorded and the influencing factors were analyzed at the end of the radiation treatment. Results: Radiotherapy-induced acute dermatitis in patients with breast-conserving surgery was relatively mild. Among the 173 patients, 33 cases had no obvious changes in the skin (grade 0; 121 cases had grade 1 skin reactions, manifested as local dark erythema and dry peeling; 29 cases had grade 2 skin reactions, characterized by edema, hyperemia, or erosion part; no grade 3 cases of skin reactions were observed. The incidence of grade 0, grade 1, and grade 2 reactions in all patients was 19.1%, 69.9%, and 11.0%, respectively. The severity of skin acute reaction is independent of the tumor sites, molecular subtypes, patients’ age, and irradiation modalities, but it

Head and neck cancers: clinical benefits of three-dimensional conformal radiotherapy and of intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Giraud, P.; Jaulerry, C.; Brunin, F.; Zefkili, S.; Helfre, S.; Chauvet, I.; Rosenwald, J.C.; Cosset, J.M.

2002-01-01

The conformal radiotherapy approach, three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT), is based on modern imaging modalities, efficient 3-D treatment planning systems, sophisticated immobilization systems and rigorous quality assurance and treatment verification. The central objective of conformal radiotherapy is to ensure a high dose distribution tailored to the limits of the target volume while reducing exposure of normal tissues. These techniques would then allow further tumor dose escalation. Head-and-neck tumors are some of the most attractive localizations to test conformal radiotherapy. They combine ballistic difficulties due to particularly complex shapes (nasopharynx, ethmoid) and problems due to the number and low tolerance of neighbouring organs like parotids, eyes, brainstem and spinal cord. The therapeutic irradiation of head-and-neck tumors thus remains a challenge for the radiation oncologist. Conformal radiotherapy does have a significant potential for improving local control and reducing toxicity when compared to standard radiotherapy. However, in the absence of prospective randomized trials, it is somewhat difficult at present to evaluate the real benefits drawn from 3DCRT and IMRT. The published clinical reports on the use of conformal radiotherapy are essentially dealing with dosimetric comparisons on relatively small numbers of patients. Recently, a few publications have emphasized the clinical experience several precursor teams with a suitable follow-up. This paper describes the current state-of-the-art of 3DCRT and IMRT in order to evaluate the impact of these techniques on head-and-neck cancers irradiation. (authors)

Intensity-modulated radiotherapy -the State of the Art

International Nuclear Information System (INIS)

Ling, C.

2002-01-01

Full text: In the last two decades of the last century, the development of three-dimensional conformal radiotherapy (3D-CRT) has substantially reduces the volume of critical organs irradiated to high doses, and has permitted the increase of tumor dose without concomitant increase in normal tissue complication. At Memorial Sloan Kettering Cancer Center, a clinical trial in cancer of the prostate has accrued >1600 patient and the prescription dose has been escalated to 81 Gy with 3D-CRT, and to 86.4 Gy using intensity modulated radiotherapy (IMRT), with promising results. 3D-CRT and IMRT involves the delineation of target and non-target structures from patient-specific 3D image data-sets (primarily CT, sometimes supplemented with MRI, PET etc.), the calculation and display of 3D dose distributions, the analysis and evaluation of structure-specific dose-volume data (DVH-dose volume histogram), radiation delivery with computer-controlled multileaf collimators (MLC), and treatment verification with electronic portal images. However, the dose distribution conformality achieved with 3D-CRT can be further improved by the use of computer-optimized IMRT. In addition, the treatment design phase of 3D-CRT involves several iterative steps and can be time-consuming, particularly when the anatomical geometry is complex. Thus, IMRT is an incremental advance from 3D-CRT with two key enhancements: 1) computerized iterative treatment plan optimization, and 2) the use of intensity-modulated radiation beams. To deliver the IM beams, one efficacious approach is to use MLC in the dynamic mode, using the so-called sliding-window technique, i.e. the leaves of the MLC are in motion while the radiation is being delivered. Since 1995, we have treated over 1500 patients with IMRT. This discussion shall describe the physical aspects of IMRT, emphasizing those features and benefits unique to this approach. Pertinent clinical results will also be briefly presented

Benchmarking Dosimetric Quality Assessment of Prostate Intensity-Modulated Radiotherapy

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Senthi, Sashendra, E-mail: sasha.senthi@petermac.org [Division of Radiation Oncology, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Gill, Suki S. [Division of Radiation Oncology, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Haworth, Annette; Kron, Tomas; Cramb, Jim [Department of Physical Sciences, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Rolfo, Aldo [Radiation Therapy Services, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Thomas, Jessica [Biostatistics and Clinical Trials, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Duchesne, Gillian M. [Division of Radiation Oncology, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia); Hamilton, Christopher H.; Joon, Daryl Lim [Radiation Oncology Department, Austin Repatriation Hospital, Heidelberg, VIC (Australia); Bowden, Patrick [Radiation Oncology Department, Tattersall' s Cancer Center, East Melbourne, VIC (Australia); Foroudi, Farshad [Division of Radiation Oncology, Peter MacCallum Cancer Center, East Melbourne, VIC (Australia)

2012-02-01

Purpose: To benchmark the dosimetric quality assessment of prostate intensity-modulated radiotherapy and determine whether the quality is influenced by disease or treatment factors. Patients and Methods: We retrospectively analyzed the data from 155 consecutive men treated radically for prostate cancer using intensity-modulated radiotherapy to 78 Gy between January 2007 and March 2009 across six radiotherapy treatment centers. The plan quality was determined by the measures of coverage, homogeneity, and conformity. Tumor coverage was measured using the planning target volume (PTV) receiving 95% and 100% of the prescribed dose (V{sub 95%} and V{sub 100%}, respectively) and the clinical target volume (CTV) receiving 95% and 100% of the prescribed dose. Homogeneity was measured using the sigma index of the PTV and CTV. Conformity was measured using the lesion coverage factor, healthy tissue conformity index, and the conformity number. Multivariate regression models were created to determine the relationship between these and T stage, risk status, androgen deprivation therapy use, treatment center, planning system, and treatment date. Results: The largest discriminatory measurements of coverage, homogeneity, and conformity were the PTV V{sub 95%}, PTV sigma index, and conformity number. The mean PTV V{sub 95%} was 92.5% (95% confidence interval, 91.3-93.7%). The mean PTV sigma index was 2.10 Gy (95% confidence interval, 1.90-2.20). The mean conformity number was 0.78 (95% confidence interval, 0.76-0.79). The treatment center independently influenced the coverage, homogeneity, and conformity (all p < .0001). The planning system independently influenced homogeneity (p = .038) and conformity (p = .021). The treatment date independently influenced the PTV V{sub 95%} only, with it being better at the start (p = .013). Risk status, T stage, and the use of androgen deprivation therapy did not influence any aspect of plan quality. Conclusion: Our study has benchmarked measures

Quality control of specific patient in radiotherapy with modulated intensity

International Nuclear Information System (INIS)

Aberbuj, P D; Tapia Coca, R C

2012-01-01

In this work we comment the details of the patient specific quality controls of the first Intensity Modulated Radiotherapy treatment done at Roffo Institute. These controls consisted in two sets of measurements: absolute dose with ionization chamber and relative dose with two dosimetric systems (Gafchromic EBT2 radiochromic films and the PTW 729 ionization chambers array). Two of the filters did not pass the dosimetrical tests, and they were manufactured again. The new filters passed the tests. For the relative two-dimensional measurements the radiochromic films had a better performance than the array due to their higher spatial resolution (author)

Estimating the costs of intensity-modulated and 3-dimensional conformal radiotherapy in Ontario.

Science.gov (United States)

Yong, J H E; McGowan, T; Redmond-Misner, R; Beca, J; Warde, P; Gutierrez, E; Hoch, J S

2016-06-01

Radiotherapy is a common treatment for many cancers, but up-to-date estimates of the costs of radiotherapy are lacking. In the present study, we estimated the unit costs of intensity-modulated radiotherapy (imrt) and 3-dimensional conformal radiotherapy (3D-crt) in Ontario. An activity-based costing model was developed to estimate the costs of imrt and 3D-crt in prostate cancer. It included the costs of equipment, staff, and supporting infrastructure. The framework was subsequently adapted to estimate the costs of radiotherapy in breast cancer and head-and-neck cancer. We also tested various scenarios by varying the program maturity and the use of volumetric modulated arc therapy (vmat) alongside imrt. From the perspective of the health care system, treating prostate cancer with imrt and 3D-crt respectively cost $12,834 and $12,453 per patient. The cost of radiotherapy ranged from $5,270 to $14,155 and was sensitive to analytic perspective, radiation technique, and disease site. Cases of head-and-neck cancer were the most costly, being driven by treatment complexity and fractions per treatment. Although imrt was more costly than 3D-crt, its cost will likely decline over time as programs mature and vmat is incorporated. Our costing model can be modified to estimate the costs of 3D-crt and imrt for various disease sites and settings. The results demonstrate the important role of capital costs in studies of radiotherapy cost from a health system perspective, which our model can accommodate. In addition, our study established the need for future analyses of imrt cost to consider how vmat affects time consumption.

Dosimetric analysis of testicular doses in prostate intensity-modulated and volumetric-modulated arc radiation therapy at different energy levels

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Onal, Cem, E-mail: hcemonal@hotmail.com; Arslan, Gungor; Dolek, Yemliha; Efe, Esma

2016-01-01

The aim of this study is to evaluate the incidental testicular doses during prostate radiation therapy with intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc radiotherapy (VMAT) at different energies. Dosimetric data of 15 patients with intermediate-risk prostate cancer who were treated with radiotherapy were analyzed. The prescribed dose was 78 Gy in 39 fractions. Dosimetric analysis compared testicular doses generated by 7-field intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy with a single arc at 6, 10, and 15 MV energy levels. Testicular doses calculated from the treatment planning system and doses measured from the detectors were analyzed. Mean testicular doses from the intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy per fraction calculated in the treatment planning system were 16.3 ± 10.3 cGy vs 21.5 ± 11.2 cGy (p = 0.03) at 6 MV, 13.4 ± 10.4 cGy vs 17.8 ± 10.7 cGy (p = 0.04) at 10 MV, and 10.6 ± 8.5 cGy vs 14.5 ± 8.6 cGy (p = 0.03) at 15 MV, respectively. Mean scattered testicular doses in the phantom measurements were 99.5 ± 17.2 cGy, 118.7 ± 16.4 cGy, and 193.9 ± 14.5 cGy at 6, 10, and 15 MV, respectively, in the intensity-modulated radiotherapy plans. In the volumetric-modulated arc radiotherapy plans, corresponding testicular doses per course were 90.4 ± 16.3 cGy, 103.6 ± 16.4 cGy, and 139.3 ± 14.6 cGy at 6, 10, and 15 MV, respectively. In conclusions, this study was the first to measure the incidental testicular doses by intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy plans at different energy levels during prostate-only irradiation. Higher photon energy and volumetric-modulated arc radiotherapy plans resulted in higher incidental testicular doses compared with lower photon energy and intensity-modulated radiotherapy plans.

Dose profile analysis of small fields in intensity modulated radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Medel B, E. [IMSS, Centro Medico Nacional Manuel Avila Camacho, Calle 2 Nte. 2004, Barrio de San Francisco, 72090 Puebla, Pue. (Mexico); Tejeda M, G.; Romero S, K., E-mail: romsakaren@gmail.com [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Fisico Matematicas, Av. San Claudio y 18 Sur, Ciudad Universitaria, 72570 Puebla, Pue.(Mexico)

2015-10-15

Full text: Small field dosimetry is getting a very important worldwide task nowadays. The use of fields of few centimeters is more common with the introduction of sophisticated techniques of radiation therapy, as Intensity Modulated Radiotherapy (IMRT). In our country the implementation of such techniques is just getting started and whit it the need of baseline data acquisition. The dosimetry under small field conditions represents a challenge for the physicists community. In this work, a dose profile analysis was done, using various types of dosimeters for further comparisons. This analysis includes the study of quality parameters as flatness, symmetry, penumbra, and other in-axis measurements. (Author)

The clinical implementation of respiratory-gated intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Keall, Paul; Vedam, Sastry; George, Rohini; Bartee, Chris; Siebers, Jeffrey; Lerma, Fritz; Weiss, Elisabeth; Chung, Theodore

2006-01-01

The clinical use of respiratory-gated radiotherapy and the application of intensity-modulated radiotherapy (IMRT) are 2 relatively new innovations to the treatment of lung cancer. Respiratory gating can reduce the deleterious effects of intrafraction motion, and IMRT can concurrently increase tumor dose homogeneity and reduce dose to critical structures including the lungs, spinal cord, esophagus, and heart. The aim of this work is to describe the clinical implementation of respiratory-gated IMRT for the treatment of non-small cell lung cancer. Documented clinical procedures were developed to include a tumor motion study, gated CT imaging, IMRT treatment planning, and gated IMRT delivery. Treatment planning procedures for respiratory-gated IMRT including beam arrangements and dose-volume constraints were developed. Quality assurance procedures were designed to quantify both the dosimetric and positional accuracy of respiratory-gated IMRT, including film dosimetry dose measurements and Monte Carlo dose calculations for verification and validation of individual patient treatments. Respiratory-gated IMRT is accepted by both treatment staff and patients. The dosimetric and positional quality assurance test results indicate that respiratory-gated IMRT can be delivered accurately. If carefully implemented, respiratory-gated IMRT is a practical alternative to conventional thoracic radiotherapy. For mobile tumors, respiratory-gated radiotherapy is used as the standard of care at our institution. Due to the increased workload, the choice of IMRT is taken on a case-by-case basis, with approximately half of the non-small cell lung cancer patients receiving respiratory-gated IMRT. We are currently evaluating whether superior tumor coverage and limited normal tissue dosing will lead to improvements in local control and survival in non-small cell lung cancer

Outcome after intensity modulated radiotherapy for anaplastic thyroid carcinoma

International Nuclear Information System (INIS)

He, Xiayun; Li, Duanshu; Hu, Chaosu; Wang, Zhuoying; Ying, Hongmei; Wu, Yi

2014-01-01

Anaplastic thyroid carcinoma (ATC) is a malignancy with one of the highest fatality rates. We reviewed our recent clinical experience with intensity modulated radiotherapy (IMRT) combined with surgery and chemotherapy for the management of ATC. 13 patients with ATC who were treated by IMRT in our institution between October 2008 and February 2011, have been analyzed. The target volume for IMRT was planned to include Gross tumor volume (GTV): primary tumor plus any N + disease (66 Gy/33 F/6.6 W), with elective irradiation of thyroid bed, bilateral level II through VI and mediastinal lymph nodes to the level of the carina (54-60 Gy). Seven patients received surgical intervention and eleven patients had chemotherapy. The median radiotherapy dose to GTV was 60 Gy/30 fractions/6 weeks. The median survival time of the 13 patients was 9 months. The direct causes of death were distant metastases (75%) and progression of the locoregional disease (25%). Ten patients were spared dyspnea and tracheostomy because their primary neck lesion did not progress. The results showed that IMRT combined by surgery and chemotherapy for ATC might be beneficial to improve locoregional control. Further new therapies are needed to control metastases

Implementation of intensity-modulated conformational radiotherapy for cervical cancers at the Alexis Vautrin Centre

International Nuclear Information System (INIS)

Renard-Oldrini, Sophie

2010-01-01

As platinum salt based concomitant conformational radiotherapy and chemotherapy have been used as a standard treatment for cervical cancers but resulted in digestive and haematological toxicities, this research thesis reports the application of intensity-modulated conformational radiation therapy. After having recalled some epidemiological, anatomical aspects, diagnosis and treatments aspects regarding cervical cancer, the author presents this last treatment technique (principles, benefits, practical implementation). The author discusses results obtained by an experiment during which seven patients have been treated by simple conformational radiation therapy, and four by intensity-modulated conformational radiation therapy. Results are discussed in terms of volumes (clinical target volume, growth target volume, planned target volume), dosimetric results, toxicities (urine and skin), weight loss [fr

Comparison of Heart and Coronary Artery Doses Associated With Intensity-Modulated Radiotherapy Versus Three-Dimensional Conformal Radiotherapy for Distal Esophageal Cancer

Energy Technology Data Exchange (ETDEWEB)

Kole, Thomas P.; Aghayere, Osarhieme; Kwah, Jason [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yorke, Ellen D. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Goodman, Karyn A., E-mail: goodmank@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-08-01

Purpose: To compare heart and coronary artery radiation exposure using intensity-modulated radiotherapy (IMRT) vs. four-field three-dimensional conformal radiotherapy (3D-CRT) treatment plans for patients with distal esophageal cancer undergoing chemoradiation. Methods and Materials: Nineteen patients with distal esophageal cancers treated with IMRT from March 2007 to May 2008 were identified. All patients were treated to 50.4 Gy with five-field IMRT plans. Theoretical 3D-CRT plans with four-field beam arrangements were generated. Dose-volume histograms of the planning target volume, heart, right coronary artery, left coronary artery, and other critical normal tissues were compared between the IMRT and 3D-CRT plans, and selected parameters were statistically evaluated using the Wilcoxon rank-sum test. Results: Intensity-modulated radiotherapy treatment planning showed significant reduction (p < 0.05) in heart dose over 3D-CRT as assessed by average mean dose (22.9 vs. 28.2 Gy) and V30 (24.8% vs. 61.0%). There was also significant sparing of the right coronary artery (average mean dose, 23.8 Gy vs. 35.5 Gy), whereas the left coronary artery showed no significant improvement (mean dose, 11.2 Gy vs. 9.2 Gy), p = 0.11. There was no significant difference in percentage of total lung volume receiving at least 10, 15, or 20 Gy or in the mean lung dose between the planning methods. There were also no significant differences observed for the kidneys, liver, stomach, or spinal cord. Intensity-modulated radiotherapy achieved a significant improvement in target conformity as measured by the conformality index (ratio of total volume receiving 95% of prescription dose to planning target volume receiving 95% of prescription dose), with the mean conformality index reduced from 1.56 to 1.30 using IMRT. Conclusions: Treatment of patients with distal esophageal cancer using IMRT significantly decreases the exposure of the heart and right coronary artery when compared with 3D

Postoperative Intensity-Modulated Radiotherapy for Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear: Treatment Outcomes, Marginal Misses, and Perspective on Target Delineation

International Nuclear Information System (INIS)

Chen, Wan-Yu; Kuo, Sung-Hsin; Chen, Yu-Hsuan; Lu, Szu-Huai; Tsai, Chiao-Ling; Chia-Hsien Cheng, Jason; Hong, Ruey-Long; Chen, Ya-Fang; Hsu, Chuan-Jen; Lin, Kai-Nan; Ko, Jenq-Yuh; Lou, Pei-Jen; Wang, Cheng-Ping; Chong, Fok-Ching; Wang, Chun-Wei

2012-01-01

Purpose: To report outcomes of the rare disease of squamous cell carcinoma (SCC) of the external auditory canal (EAC) and middle ear treated with surgery and postoperative intensity-modulated radiotherapy (IMRT). Failure patterns related to spatial dose distribution were also analyzed to provide insight into target delineation. Methods and Materials: A retrospective review was conducted of the records of 11 consecutive patients with SCC of the EAC and middle ear who were treated with curative surgery and postoperative IMRT at one institution between January 2007 and February 2010. The prescribed IMRT dose was 60 to 66 Gy at 2 Gy per fraction. Three patients also received concurrent cisplatin-based chemotherapy, and 1 patient received concurrent oral tegafur/uracil. The median follow-up time was 19 months (range, 6–33 months). Results: Four patients had locoregional recurrence, yielding an estimated 2-year locoregional control rate of 70.7%. Among them, 1 patient had persistent disease after treatment, and 3 had marginal recurrence. Distant metastasis occurred in 1 patient after extensive locoregional recurrence, yielding an estimated 2-year distant control rate of 85.7%. The estimated 2-year overall survival was 67.5%. The three cases of marginal recurrence were near the preauricular space and glenoid fossa of the temporomandibular joint, adjacent to the apex of the ear canal and glenoid fossa of the temporomandibular joint, and in the postauricular subcutaneous area and ipsilateral parotid nodes, respectively. Conclusions: Marginal misses should be recognized to improve target delineation. When treating SCC of the EAC and middle ear, care should be taken to cover the glenoid fossa of the temporomandibular joint and periauricular soft tissue. Elective ipsilateral parotid irradiation should be considered. The treatment planning procedure should also be refined to balance subcutaneous soft-tissue dosimetry and toxicity.

Postoperative Intensity-Modulated Radiotherapy for Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear: Treatment Outcomes, Marginal Misses, and Perspective on Target Delineation

Energy Technology Data Exchange (ETDEWEB)

Chen, Wan-Yu [Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Kuo, Sung-Hsin [Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan (China); Chen, Yu-Hsuan; Lu, Szu-Huai; Tsai, Chiao-Ling [Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Chia-Hsien Cheng, Jason [Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan (China); Graduate Institute of Oncology, National Taiwan University College of Medicine, Taipei, Taiwan (China); Hong, Ruey-Long [Division of Medical Oncology, Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Chen, Ya-Fang [Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan (China); Hsu, Chuan-Jen; Lin, Kai-Nan; Ko, Jenq-Yuh; Lou, Pei-Jen; Wang, Cheng-Ping [Department of Otolaryngology, National Taiwan University Hospital, Taipei, Taiwan (China); Chong, Fok-Ching [Graduate Institute of Electrical Engineering, National Taiwan University, Taipei, Taiwan (China); Wang, Chun-Wei, E-mail: cwwang@ntuh.gov.tw [Graduate Institute of Electrical Engineering, National Taiwan University, Taipei, Taiwan (China)

2012-03-15

Purpose: To report outcomes of the rare disease of squamous cell carcinoma (SCC) of the external auditory canal (EAC) and middle ear treated with surgery and postoperative intensity-modulated radiotherapy (IMRT). Failure patterns related to spatial dose distribution were also analyzed to provide insight into target delineation. Methods and Materials: A retrospective review was conducted of the records of 11 consecutive patients with SCC of the EAC and middle ear who were treated with curative surgery and postoperative IMRT at one institution between January 2007 and February 2010. The prescribed IMRT dose was 60 to 66 Gy at 2 Gy per fraction. Three patients also received concurrent cisplatin-based chemotherapy, and 1 patient received concurrent oral tegafur/uracil. The median follow-up time was 19 months (range, 6-33 months). Results: Four patients had locoregional recurrence, yielding an estimated 2-year locoregional control rate of 70.7%. Among them, 1 patient had persistent disease after treatment, and 3 had marginal recurrence. Distant metastasis occurred in 1 patient after extensive locoregional recurrence, yielding an estimated 2-year distant control rate of 85.7%. The estimated 2-year overall survival was 67.5%. The three cases of marginal recurrence were near the preauricular space and glenoid fossa of the temporomandibular joint, adjacent to the apex of the ear canal and glenoid fossa of the temporomandibular joint, and in the postauricular subcutaneous area and ipsilateral parotid nodes, respectively. Conclusions: Marginal misses should be recognized to improve target delineation. When treating SCC of the EAC and middle ear, care should be taken to cover the glenoid fossa of the temporomandibular joint and periauricular soft tissue. Elective ipsilateral parotid irradiation should be considered. The treatment planning procedure should also be refined to balance subcutaneous soft-tissue dosimetry and toxicity.

SU-E-P-58: Dosimetric Study of Conventional Intensity-Modulated Radiotherapy and Knowledge-Based Radiation Therapy for Postoperation of Cervix Cancer

Energy Technology Data Exchange (ETDEWEB)

Ma, C; Yin, Y [Shandong Tumor Hospital, Jinan, Shandong Provice (China)

2015-06-15

Purpose: To compare the dosimetric difference of the target volume and organs at risk(OARs) between conventional intensity-modulated radiotherapy(C-IMRT) and knowledge-based radiation therapy (KBRT) plans for cervix cancer. Methods: 39 patients with cervical cancer after surgery were randomly selected, 20 patient plans were used to create the model, the other 19 cases used for comparative evaluation. All plans were designed in Eclipse system. The prescription dose was 30.6Gy, 17 fractions, OARs dose satisfied to the clinical requirement. A paired t test was used to evaluate the differences of dose-volume histograms (DVH). Results: Comparaed to C-IMRT plan, the KBRT plan target can achieve the similar target dose coverage, D98,D95,D2,HI and CI had no difference (P≥0.05). The dose of rectum, bladder and femoral heads had no significant differences(P≥0.05). The time was used to design treatment plan was significant reduced. Conclusion: This study shows that postoperative radiotherapy of cervical KBRT plans can achieve the similar target and OARs dose, but the shorter designing time.

Outcomes of WHO Grade I Meningiomas Receiving Definitive or Postoperative Radiotherapy

International Nuclear Information System (INIS)

Tanzler, Emily; Morris, Christopher G.; Kirwan, Jessica M.; Amdur, Robert J.; Mendenhall, William M.

2011-01-01

Purpose: We analyzed long-term local control and complications in patients with either pathologically confirmed or clinical World Health Organization Grade I meningiomas treated with definitive or postoperative radiotherapy (RT) at the University of Florida. Methods: Between 1984 and 2006, 146 patients were treated with definitive (n = 88) or postoperative RT after subtotal resection (n = 57) or gross total resection (n = 1). Patients were treated with conventional (n = 41), stereotactic (n = 103), or intensity-modulated RT (n = 2) to a median dose of 52.7 Gy and followed for a median of 7.3 years (range, 0.6-22.0 years) Results: The local control rates at 5 and 10 years were as follows: definitive RT, 99% and 99%; postoperative RT, 96% and 93%; and overall, 97% and 96%, respectively. The 5- and 10-year cause-specific survival rates were as follows: definitive RT 94% and 94%, postoperative RT, 100% and 96%; and overall, 96% and 95%, respectively. The 5- and 10-year overall survival rates were as follows: definitive RT, 81% and 75%; postoperative RT, 96% and 85%; and overall, 87% and 79%, respectively. Severe RT complications occurred in 6.8% of patients; severe surgery-related complications occurred in 10 (17%) of 58 patients treated surgically. Conclusions: The likelihood of cure after definitive RT or following subtotal resection is excellent. However, a small population of patients experience severe complications, even at the moderate dose used for this disease.

Nasopharynx carcinoma treatment: from the conventional radiotherapy to the conformal radiotherapy with intensity modulation; Traitement du carcinome du nasopharynx: de la radiotherapie conventionnelle a la radiotherapie conformationnelle avec modulation d'intensite

Energy Technology Data Exchange (ETDEWEB)

Mokaouim, K.; Grehange, G.; Truc, G.; Peingnaux, K.; Martin, E.; Zanetta, S.; Bruchon, Y.; Bonnetain, F.; Maingon, P. [Centre Georges-Francois Leclerc, 21 - Dijon (France)

2009-10-15

The objective of this study was to evaluate retrospectively the impact of factors linked to the radiotherapy realisation on the local and locoregional control, the global survival, the survival without disease of patients suffering of naso-pharynx carcinoma. Conclusion: the patients suffering of a nasopharynx carcinoma treated by irradiation associated to chemotherapy have an improved global survival and an improved survival without disease. The conformal radiotherapy with or without modulated intensity reduce the risk of serous otitis, trismus and xerostomia at long term. It seems necessary to realize multi centric studies with a longer period of follow up before asserting the advantages of the I.M.R.T. in comparison to the classical and conformal technique in the treatment of naso-pharynx carcinomas. (N.C.)

Transition from 2-D radiotherapy to 3-D conformal and intensity modulated radiotherapy

International Nuclear Information System (INIS)

2008-05-01

Cancer is one of the leading causes of death globally and radiotherapy is currently an essential component in the management of cancer patients, either alone or in combination with surgery or chemotherapy, both for cure or palliation. It is now recognized that safe and effective radiotherapy service needs not only substantial capital investment in radiotherapy equipment and specially designed facilities but also continuous investment in maintenance and upgrading of the equipment to comply with the technical progress, but also in training the staff. The recent IAEA-TECDOC publication 'Setting up a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects' provides general guidelines for designing and implementing radiotherapy services in Member States. Advances in computer technology have enabled the possibility of transitioning from basic 2- dimensional treatment planning and delivery (2-D radiotherapy) to a more sophisticated approach with 3-dimensional conformal radiotherapy (3-D CRT). Whereas 2-D radiotherapy can be applied with simple equipment, infrastructure and training, transfer to 3-D conformal treatments requires more resources in technology, equipment, staff and training. A novel radiation treatment approach using Intensity Modulated Radiation Therapy (IMRT) that optimizes the delivery of radiation to irregularly shaped tumour volumes demands even more sophisticated equipment and seamless teamwork, and consequentially more resources, advanced training and more time for treatment planning and verification of dose delivery than 3-D CRT. Whereas 3-D CRT can be considered as a standard, IMRT is still evolving. Due to the increased interest of Member States to the modern application of radiotherapy the IAEA has received a number of requests for guidance coming from radiotherapy departments that wish to upgrade their facilities to 3-D CRT and IMRT through Technical Cooperation programme. These requests are expected to increase

Feasibility of intensity-modulated and image-guided radiotherapy for locally advanced esophageal cancer

International Nuclear Information System (INIS)

Nguyen, Nam P; Desai, Anand; Smith-Raymond, Lexie; Jang, Siyoung; Vock, Jacqueline; Vinh-Hung, Vincent; Chi, Alexander; Vos, Paul; Pugh, Judith; Vo, Richard A; Ceizyk, Misty

2014-01-01

In this study the feasibility of intensity-modulated radiotherapy (IMRT) and tomotherapy-based image-guided radiotherapy (IGRT) for locally advanced esophageal cancer was assessed. A retrospective study of ten patients with locally advanced esophageal cancer who underwent concurrent chemotherapy with IMRT (1) and IGRT (9) was conducted. The gross tumor volume was treated to a median dose of 70 Gy (62.4-75 Gy). At a median follow-up of 14 months (1-39 months), three patients developed local failures, six patients developed distant metastases, and complications occurred in two patients (1 tracheoesophageal fistula, 1 esophageal stricture requiring repeated dilatations). No patients developed grade 3-4 pneumonitis or cardiac complications. IMRT and IGRT may be effective for the treatment of locally advanced esophageal cancer with acceptable complications

Three dimensional conformal postoperative radiotherapy for ...

African Journals Online (AJOL)

Introduction: Postoperative radiotherapy of the parotid gland could be achieved with various radiotherapy techniques. However they irradiate differently the surrounding organs at risk (OARs) in particular the cochlea, oral cavity & contralateral parotid causing significant increase in the risk of oral mucositis, xerostomia, and ...

Changes in Pulmonary Function After Three-Dimensional Conformal Radiotherapy, Intensity-Modulated Radiotherapy, or Proton Beam Therapy for Non-Small-Cell Lung Cancer

International Nuclear Information System (INIS)

Lopez Guerra, Jose L.; Gomez, Daniel R.; Zhuang Yan; Levy, Lawrence B.; Eapen, George; Liu, Hongmei; Mohan, Radhe; Komaki, Ritsuko; Cox, James D.; Liao Zhongxing

2012-01-01

Purpose: To investigate the extent of change in pulmonary function over time after definitive radiotherapy for non-small-cell lung cancer (NSCLC) with modern techniques and to identify predictors of changes in pulmonary function according to patient, tumor, and treatment characteristics. Patients and Methods: We analyzed 250 patients who had received ≥60 Gy radio(chemo)therapy for primary NSCLC in 1998–2010 and had undergone pulmonary function tests before and within 1 year after treatment. Ninety-three patients were treated with three-dimensional conformal radiotherapy, 97 with intensity-modulated radiotherapy, and 60 with proton beam therapy. Postradiation pulmonary function test values were evaluated among individual patients compared with the same patient’s preradiation value at the following time intervals: 0–4 (T1), 5–8 (T2), and 9–12 (T3) months. Results: Lung diffusing capacity for carbon monoxide (DLCO) was reduced in the majority of patients along the three time periods after radiation, whereas the forced expiratory volume in 1 s per unit of vital capacity (FEV1/VC) showed an increase and decrease after radiation in a similar percentage of patients. There were baseline differences (stage, radiotherapy dose, concurrent chemotherapy) among the radiation technology groups. On multivariate analysis, the following features were associated with larger posttreatment declines in DLCO: pretreatment DLCO, gross tumor volume, lung and heart dosimetric data, and total radiation dose. Only pretreatment DLCO was associated with larger posttreatment declines in FEV1/VC. Conclusions: Lung diffusing capacity for carbon monoxide is reduced in the majority of patients after radiotherapy with modern techniques. Multiple factors, including gross tumor volume, preradiation lung function, and dosimetric parameters, are associated with the DLCO decline. Prospective studies are needed to better understand whether new radiation technology, such as proton beam therapy

A comparative dosimetric study of conventional, conformal and intensity-modulated radiotherapy in postoperative pelvic irradiation of cervical cancer

International Nuclear Information System (INIS)

Li Bin; An Jusheng; Wu Lingying; Huang Manni; Gao Juzhen; Xu Yingjie; Dai Jianrong

2008-01-01

Objective: To evaluate target-volume coverage and organ at risk (OAR) protection achieved with conventional radiotherapy (CRT), three dimensional conformal radiotherapy (3DCRT), and intensity-modulated radiotherapy(IMRT) through dosimetric comparison in patients with cervical cancer after hysterectomy. Methods: The planning CT scans of 10 patients treated with pelvic radiation after hysterectomy for cervical cancer were used to generate CRT, 3DCRT and IMRT plans for this study. Clinical target volume(CTV) was contoured on the individual axial CT slices of every patient. The CTV was then uniformly expanded by 1.0 cm to create the planning target volume (PTV). The small bowel, rectum, bladder, bone marrow, ovaries, and femoral heads were outlined for the organ at risk (OAR) evaluation. The CRT, 3DCRT and IMRT plans were generated using commercial planning software. CRT plan was prescribed to deliver 45 Gy to the reference point, while IMRT and 3DCRT plans were 45 Gy to 95% of the PTV. Isodose line and dose volume histograms(DVH) were used to evaluate the dose distribution in CTV and OAR. Results: For 10 patients, the average volume of CTV receiving the prescribed dose of CRT was significantly lower than 3DCRT(Q=8.27, P<0.01) and IMRT(Q=8.37, P<0.01), respectively. Comparing with the CRT plan, the 3DCRT and IMRT plans notably reduced the volume of bowel at 30 and 45 Gy levels. The IMRT plan significantly spared rectum and bladder at 30 and 45 Gy levels comparing with the CRT (P<0.01) and 3DCRT(P<0.05) plans, while the 3DCRT plan significantly spared rectum and bladder at 45 Gy level comparing with the CRT(P<0.01) plans. For 4 patients with ovarian transposition, the average doses of ovary over 3 Gy were 2 patients with the 3 DCRT and IMRT plans, and 2 with all three plans. Conclusions: IMRT and 3DCRT are superior to CRT in improving dose coverage of target volume and sparing of OAR, while IMRT being the best. The superiority of IMRT and 3DCRT is obvious in sparing

Induction chemotherapy with nedaplatin with 5-FU followed by intensity-modulated radiotherapy concurrent with chemotherapy for locoregionally advanced nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Zheng Jijun; Wang Ge; Yang, G.Y.

2010-01-01

This Phase II study was conducted to evaluate the activity and feasibility of a regimen of nedaplatin and 5-fluorouracil as induction chemotherapy, followed by intensity-modulated radiotherapy concurrent with chemotherapy in patients with locoregionally advanced nasopharyngeal carcinoma. Patients received neoadjuvant chemotherapy comprised two cycles of 5-fluorouracil at 700 mg/m 2 /day administered on days 1-4 as continuous intravenous infusion and nedaplatin (100 mg/m 2 administered intravenous (i.v.) over 2 h) given after the administration of 5-fluorouracil on day 1, repeated every 3 weeks, followed by intensity-modulated radiotherapy concurrent with nedaplatin. During intensity-modulated radiotherapy, nedaplatin was administered at a dose of 100 mg/m 2 intravenous infusion on days 1, 22 and 43, given -60 min before radiation. Fifty-nine (95.8%) of the 60 patients were assessable for response. Thirty-eight cases of complete response and 14 cases of partial response were confirmed after completion of chemoradiation, with the objective response rate of 86.7% (95% confidence interval (CI), 78.1-95.3%). The median follow-up period was 48 months (range, 30-62 months). The 3-year progression-free survival and overall survival were 75.0% (95% CI, 63.0-87.0%) and 85.5% (95% CI, 75.9-95.1%). No patient showed Grade 3 or higher renal dysfunction. The most commonly observed late effect was xerostomia, but the severity diminished over time, and the detectable xerostomia at 24 months was 10.2%. There were no treatment-related deaths during this study. Neoadjuvant chemotherapy with nedaplatin and 5-fluorouracil followed by concomitant nedaplatin and intensity-modulated radiotherapy is an effective and safe treatment for Southern China patients affected by locoregionally advanced nasopharyngeal carcinoma. (author)

Post-nerve-sparing prostatectomy, dose-escalated intensity-modulated radiotherapy: effect on erectile function

International Nuclear Information System (INIS)

Bastasch, Michael D.; Teh, Bin S.; Mai, W.-Y.; Carpenter, L. Steven; Lu, Hsin H.; Chiu, J. Kam; Woo, Shiao Y.; Grant, Walter H.; Miles, Brian J.; Kadmon, Dov; Butler, E. Brian

2002-01-01

Purpose: The advent of widespread prostate-specific antigen screening has resulted in more younger, potent men being diagnosed with early-stage, organ-confined prostate cancer amenable to definitive surgery. Nerve-sparing prostatectomy is a relatively new surgical advance in the treatment of prostate cancer. Very few data exist on the effect of postoperative radiotherapy (RT) on erectile function after nerve-sparing prostatectomy. They are based on conventional techniques using moderate doses of radiation, 45-54 Gy. Intensity-modulated RT (IMRT) is becoming more widespread because it allows dose escalation with increased sparing of the surrounding normal tissue. We investigated the effect of postprostatectomy, high-dose IMRT on patients' erectile function. Methods and Materials: A review of patient records found 51 patients treated between April 1998 and December 2000 with IMRT after unilateral or bilateral nerve-sparing prostatectomy. The pathologic disease stage in these patients was T2 in 47.4% and T3 in 52.6%. Postoperatively, 4 patients received hormonal ablation consisting of one injection of Lupron Depot (30 mg) 2 months before RT. The median age was 65 years (range 46-77) at the time of RT. The prescribed dose was 64 Gy (range 60-66). The mean dose was 69.6 Gy (range 64.0-72.3). Erectile function was assessed before and after RT by questionnaires. Sexual potency was defined as erectile rigidity adequate for vaginal penetration. Results: Of the 51 patients, 18 (35.3%) maintained their potency and 33 (64.7%) became impotent after nerve-sparing prostatectomy. Patients who underwent bilateral nerve-sparing prostatectomy had higher rates of postoperative potency than did those who underwent unilateral nerve-sparing surgery (72.2% vs. 27.8%; p=0.025). The follow-up for the entire group was 19.5 months. All 18 patients (100%) who were potent postoperatively remained potent after RT. The median follow-up for the 18 potent patients was 27.2 months, significantly

Intensity-Modulated Radiotherapy for Cervical Lymph Node Metastases From Unknown Primary Cancer

International Nuclear Information System (INIS)

Madani, Indira; Vakaet, Luc; Bonte, Katrien; Boterberg, Tom; Neve, Wilfried de

2008-01-01

Purpose: To compare the effectiveness of intensity-modulated radiotherapy (IMRT) and conventional (two-dimensional) radiotherapy in the treatment of cervical lymph node metastases from unknown primary cancer (UPC). Methods and Materials: Between February 2003 and September 2006, 23 patients with UPC of squamous cell carcinoma were treated with IMRT. Extended putative mucosal and bilateral nodal sites were irradiated to a median dose of 66 Gy. In 19 patients, IMRT was performed after lymph node dissection, and in 4 patients primary radiotherapy was given. The conventional radiotherapy group (historical control group) comprised 18 patients treated to a median dose of 66 Gy between August 1994 and October 2003. Results: Twenty patients completed treatment. As compared with conventional radiotherapy, the incidence of Grade 3 acute dysphagia was significantly lower in the IMRT group (4.5% vs. 50%, p = 0.003). By 6 months, Grade 3 xerostomia was detected in 11.8% patients in the IMRT group vs. 53.4% in the historical control group (p = 0.03). No Grade 3 dysphagia or skin fibrosis was observed after IMRT but these were noted after conventional radiotherapy (26.7%, p = 0.01) and 26.7%, p = 0.03) respectively). With median follow-up of living patients of 17 months, there was no emergence of primary cancer. One patient had persistent nodal disease and another had nodal relapse at 5 months. Distant metastases were detected in 4 patients. The 2-year overall survival and distant disease-free probability after IMRT did not differ significantly from those for conventional radiotherapy (74.8% vs. 61.1% and 76.3% vs. 68.4%, respectively). Conclusions: Use of IMRT for UPC resulted in lower toxicity than conventional radiotherapy, and was similar in efficacy

Therapeutic options and postoperative wound complications after extremity soft tissue sarcoma resection and postoperative external beam radiotherapy.

Science.gov (United States)

Abouarab, Mohamed H; Salem, Iman L; Degheidy, Magdy M; Henn, Dominic; Hirche, Christoph; Eweida, Ahmad; Uhl, Matthias; Kneser, Ulrich; Kremer, Thomas

2018-02-01

Soft tissue sarcomas occur most commonly in the lower and upper extremities. The standard treatment is limb salvage surgery combined with radiotherapy. Postoperative radiotherapy is associated with wound complications. This systematic review aims to summarise the available evidence and review the literature of the last 10 years regarding postoperative wound complications in patients who had limb salvage surgical excision followed by direct closure vs flap coverage together with postoperative radiotherapy and to define the optimal timeframe for adjuvant radiotherapy after soft tissue sarcomas resection and flap reconstruction. A literature search was performed using PubMed. The following keywords were searched: limb salvage, limb-sparing, flaps, radiation therapy, radiation, irradiation, adjuvant radiotherapy, postoperative radiotherapy, radiation effects, wound healing, surgical wound infection, surgical wound dehiscence, wound healing, soft tissue sarcoma and neoplasms. In total, 1045 papers were retrieved. Thirty-seven articles were finally selected after screening of abstracts and applying dates and language filters and inclusion and exclusion criteria. Plastic surgery provides a vast number of reconstructive flap procedures that are directly linked to decreasing wound complications, especially with the expectant postoperative radiotherapy. This adjuvant radiotherapy is better administered in the first 3-6 weeks after reconstruction to allow timely wound healing and avoid local recurrence. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Dosimetric Comparison of Three-Dimensional Conformal Proton Radiotherapy, Intensity-Modulated Proton Therapy, and Intensity-Modulated Radiotherapy for Treatment of Pediatric Craniopharyngiomas

Energy Technology Data Exchange (ETDEWEB)

Boehling, Nicholas S. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Grosshans, David R., E-mail: dgrossha@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Bluett, Jaques B. [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Palmer, Matthew T. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Song, Xiaofei; Amos, Richard A.; Sahoo, Narayan [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Meyer, Jeffrey J.; Mahajan, Anita; Woo, Shiao Y. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

2012-02-01

Purpose: Cranial irradiation in pediatric patients is associated with serious long-term adverse effects. We sought to determine whether both three-dimensional conformal proton radiotherapy (3D-PRT) and intensity-modulated proton therapy (IMPT) compared with intensity-modulated radiotherapy (IMRT) decrease integral dose to brain areas known to harbor neuronal stem cells, major blood vessels, and other normal brain structures for pediatric patients with craniopharyngiomas. Methods and Materials: IMRT, forward planned, passive scattering proton, and IMPT plans were generated and optimized for 10 pediatric patients. The dose was 50.4 Gy (or cobalt Gy equivalent) delivered in 28 fractions with the requirement for planning target volume (PTV) coverage of 95% or better. Integral dose data were calculated from differential dose-volume histograms. Results: The PTV target coverage was adequate for all modalities. IMRT and IMPT yielded the most conformal plans in comparison to 3D-PRT. Compared with IMRT, 3D-PRT and IMPT plans had a relative reduction of integral dose to the hippocampus (3D-PRT, 20.4; IMPT, 51.3%{sup Asterisk-Operator }), dentate gyrus (27.3, 75.0%{sup Asterisk-Operator }), and subventricular zone (4.5, 57.8%{sup Asterisk-Operator }). Vascular organs at risk also had reduced integral dose with the use of proton therapy (anterior cerebral arteries, 33.3{sup Asterisk-Operator }, 100.0%{sup Asterisk-Operator }; middle cerebral arteries, 25.9%{sup Asterisk-Operator }, 100%{sup Asterisk-Operator }; anterior communicating arteries, 30.8{sup Asterisk-Operator }, 41.7%{sup Asterisk-Operator }; and carotid arteries, 51.5{sup Asterisk-Operator }, 77.6{sup Asterisk-Operator }). Relative reduction of integral dose to the infratentorial brain (190.7{sup Asterisk-Operator }, 109.7%{sup Asterisk-Operator }), supratentorial brain without PTV (9.6, 26.8%{sup Asterisk-Operator }), brainstem (45.6, 22.4%{sup Asterisk-Operator }), and whole brain without PTV (19.4{sup Asterisk

Simultaneous Integrated Boost Using Intensity-Modulated Radiotherapy Compared With Conventional Radiotherapy in Patients Treated With Concurrent Carboplatin and 5-Fluorouracil for Locally Advanced Oropharyngeal Carcinoma

Energy Technology Data Exchange (ETDEWEB)

Clavel, Sebastien, E-mail: sebastien.clavel@umontreal.ca [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, QC (Canada); Nguyen, David H.A.; Fortin, Bernard [Department of Radiation Oncology, Hopital Maisonneuve-Rosemont, Montreal, QC (Canada); Despres, Philippe [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, QC (Canada); Khaouam, Nader [Department of Radiation Oncology, Hopital Maisonneuve-Rosemont, Montreal, QC (Canada); Donath, David [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, QC (Canada); Soulieres, Denis [Department of Medical Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, QC (Canada); Guertin, Louis [Department of Head and Neck Surgery, Centre Hospitalier de l' Universite de Montreal, Montreal, QC (Canada); Nguyen-Tan, Phuc Felix [Department of Radiation Oncology, Hopital Maisonneuve-Rosemont, Montreal, QC (Canada)

2012-02-01

Purpose: To compare, in a retrospective study, the toxicity and efficacy of simultaneous integrated boost using intensity-modulated radiotherapy (IMRT) vs. conventional radiotherapy (CRT) in patients treated with concomitant carboplatin and 5-fluorouracil for locally advanced oropharyngeal cancer. Methods and Materials: Between January 2000 and December 2007, 249 patients were treated with definitive chemoradiation. One hundred patients had 70 Gy in 33 fractions using IMRT, and 149 received CRT at 70 Gy in 35 fractions. Overall survival, disease-free survival, and locoregional control were estimated using the Kaplan-Meier method. Results: Median follow-up was 42 months. Three-year actuarial rates for locoregional control, disease-free survival, and overall survival were 95.1% vs. 84.4% (p = 0.005), 85.3% vs. 69.3% (p = 0.001), and 92.1% vs. 75.2% (p < 0.001) for IMRT and CRT, respectively. The benefit of the radiotherapy regimen on outcomes was also observed with a Cox multivariate analysis. Intensity-modulated radiotherapy was associated with less acute dermatitis and less xerostomia at 6, 12, 24, and 36 months. Conclusions: This study suggests that simultaneous integrated boost using IMRT is associated with favorable locoregional control and survival rates with less xerostomia and acute dermatitis than CRT when both are given concurrently with chemotherapy.

Simultaneous Integrated Boost Using Intensity-Modulated Radiotherapy Compared With Conventional Radiotherapy in Patients Treated With Concurrent Carboplatin and 5-Fluorouracil for Locally Advanced Oropharyngeal Carcinoma

International Nuclear Information System (INIS)

Clavel, Sébastien; Nguyen, David H.A.; Fortin, Bernard; Després, Philippe; Khaouam, Nader; Donath, David; Soulières, Denis; Guertin, Louis; Nguyen-Tan, Phuc Felix

2012-01-01

Purpose: To compare, in a retrospective study, the toxicity and efficacy of simultaneous integrated boost using intensity-modulated radiotherapy (IMRT) vs. conventional radiotherapy (CRT) in patients treated with concomitant carboplatin and 5-fluorouracil for locally advanced oropharyngeal cancer. Methods and Materials: Between January 2000 and December 2007, 249 patients were treated with definitive chemoradiation. One hundred patients had 70 Gy in 33 fractions using IMRT, and 149 received CRT at 70 Gy in 35 fractions. Overall survival, disease-free survival, and locoregional control were estimated using the Kaplan-Meier method. Results: Median follow-up was 42 months. Three-year actuarial rates for locoregional control, disease-free survival, and overall survival were 95.1% vs. 84.4% (p = 0.005), 85.3% vs. 69.3% (p = 0.001), and 92.1% vs. 75.2% (p < 0.001) for IMRT and CRT, respectively. The benefit of the radiotherapy regimen on outcomes was also observed with a Cox multivariate analysis. Intensity-modulated radiotherapy was associated with less acute dermatitis and less xerostomia at 6, 12, 24, and 36 months. Conclusions: This study suggests that simultaneous integrated boost using IMRT is associated with favorable locoregional control and survival rates with less xerostomia and acute dermatitis than CRT when both are given concurrently with chemotherapy.

Postoperative radiotherapy for merkel cell carcinoma

International Nuclear Information System (INIS)

Inoue, Kazuya; Asakawa, Isao; Katayama, Emiko; Kajitani, Chikae; Tamamoto, Tetsuro; Hasegawa, Masatoshi; Fukumoto, Takaya; Asada, Hideo

2014-01-01

Seven patients with Merkel cell carcinoma (MCC) who visited our department of radiation oncology from February 2005 to July 2011 received postoperative radiotherapy (50-60 Gy). All patients were alive without recurrence (median follow-up period: 47.6 (14.7-88.4) months). All of them had grade 2 dermatitis, and one grade 2 oral mucositis and three grade 2 lymphedema were observed. No adverse event grade 3 (CTCAE v4.0) or over was observed. In our hospital, clinical results of postoperative radiotherapy for MCC were fairly good, and adverse events were acceptable during the follow-up period. (author)

Predictive factors of local-regional recurrences following parotid sparing intensity modulated or 3D conformal radiotherapy for head and neck cancer

International Nuclear Information System (INIS)

Feng, Mary; Jabbari, Siavash; Lin, Alexander; Bradford, Carol R.; Chepeha, Douglas B.; Teknos, Theodoros N.; Worden, Francis P.; Tsien, Christina; Schipper, Matthew J.; Wolf, Gregory T.; Dawson, Laura A.; Eisbruch, Avraham

2005-01-01

Background and purpose: Predictive factors for local-regional (LR) failures after parotid-sparing, Intensity modulated (IMRT) or 3D conformal radiotherapy for head and neck (HN) cancers were assessed. Patients and methods: One hundred and fifty-eight patients with mostly stages III-IV HN squamous cell carcinoma underwent curative bilateral neck irradiation aimed at sparing the parotid glands. Patient, tumor, and treatment factors were analyzed as predictive factors for LR failure. Results: Twenty-three patients had LR recurrence (19 in-field and four marginal). No differences were found in the doses delivered to the PTVs of patients with or without in-field recurrences. In univariate analysis, tumor site was highly predictive for LR failure in both postoperative and definitive RT patients. In postoperative RT patients, pathologic tumor size, margin status, extracapsular extension (ECE) and number of lymph node metastases, were also significantly predictive. Multivariate analysis showed tumor site (oropharynx vs. other sites) to be a significant predictor in all patients, and involved margins and number of involved lymph nodes in postoperative patients. Conclusions: Clinical rather than dosimetric factors predicted for LR failures in this series, and were similar to those reported following standard RT. These factors may aid in the selection of patients for studies of treatment intensification using IMRT

Hypofractionated Accelerated Radiotherapy Using Concomitant Intensity-Modulated Radiotherapy Boost Technique for Localized High-Risk Prostate Cancer: Acute Toxicity Results

International Nuclear Information System (INIS)

Lim, Tee S.; Cheung, Patrick; Loblaw, D. Andrew; Morton, Gerard; Sixel, Katharina E.; Pang, Geordi; Basran, Parminder; Zhang Liying; Tirona, Romeo; Szumacher, Ewa; Danjoux, Cyril; Choo, Richard; Thomas, Gillian

2008-01-01

Purpose: To evaluate the acute toxicities of hypofractionated accelerated radiotherapy (RT) using a concomitant intensity-modulated RT boost in conjunction with elective pelvic nodal irradiation for high-risk prostate cancer. Methods and Materials: This report focused on 66 patients entered into this prospective Phase I study. The eligible patients had clinically localized prostate cancer with at least one of the following high-risk features (Stage T3, Gleason score ≥8, or prostate-specific antigen level >20 ng/mL). Patients were treated with 45 Gy in 25 fractions to the pelvic lymph nodes using a conventional four-field technique. A concomitant intensity-modulated radiotherapy boost of 22.5 Gy in 25 fractions was delivered to the prostate. Thus, the prostate received 67.5 Gy in 25 fractions within 5 weeks. Next, the patients underwent 3 years of adjuvant androgen ablative therapy. Acute toxicities were assessed using the Common Terminology Criteria for Adverse Events, version 3.0, weekly during treatment and at 3 months after RT. Results: The median patient age was 71 years. The median pretreatment prostate-specific antigen level and Gleason score was 18.7 ng/L and 8, respectively. Grade 1-2 genitourinary and gastrointestinal toxicities were common during RT but most had settled at 3 months after treatment. Only 5 patients had acute Grade 3 genitourinary toxicity, in the form of urinary incontinence (n = 1), urinary frequency/urgency (n = 3), and urinary retention (n = 1). None of the patients developed Grade 3 or greater gastrointestinal or Grade 4 or greater genitourinary toxicity. Conclusion: The results of the present study have indicated that hypofractionated accelerated RT with a concomitant intensity-modulated RT boost and pelvic nodal irradiation is feasible with acceptable acute toxicity

3D-Conformal Versus Intensity-Modulated Postoperative Radiotherapy of Vaginal Vault: A Dosimetric Comparison

International Nuclear Information System (INIS)

Cilla, Savino; Macchia, Gabriella; Digesu, Cinzia; Deodato, Francesco; Romanella, Michele; Ferrandina, Gabriella; Padula, Gilbert; Picardi, Vincenzo; Scambia, Giovanni; Piermattei, Angelo; Morganti, Alessio Giuseppe

2010-01-01

We evaluated a step-and-shoot IMRT plan in the postoperative irradiation of the vaginal vault compared with equispaced beam arrangements (3-5) 3D-radiotherapy (RT) optimized plans. Twelve patients were included in this analysis. Four plans for each patient were compared in terms of dose-volume histograms, homogeneity index (HI), and conformity index (CI): (1) 3 equispaced beam arrangement 3D-RT; (2) 4 equispaced beam arrangement 3D-RT; (3) 5 equispaced beam arrangement 3D-RT; (4) step-and-shoot IMRT technique. CI showed a good discrimination between the four plans. The mean scores of CI were 0.58 (range: 0.38-0.67) for the 3F-CRT plan, 0.58 (range: 0.41-0.66) for 4F-CRT, 0.62 (range: 0.43-0.68) for 5F-CRT and 0.69 (range: 0.58-0.78) for the IMRT plan. A significant improvement of the conformity was reached by the IMRT plan (p mean , V90%, V95%, V100% was recorded for rectal and bladder irradiation with the IMRT plan. Surprisingly, IMRT supplied a significant dose reduction also for rectum and bladder V30% and V50%. A significant dosimetric advantage of IMRT over 3D-RT in the adjuvant treatment of vaginal vault alone in terms of treatment conformity and rectum and bladder sparing is shown.

Patterns of local-regional failure after primary intensity modulated radiotherapy for nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Kong, Fangfang; Ying, Hongmei; Du, Chengrun; Huang, Shuang; Zhou, Junjun; Chen, Junchao; Sun, Lining; Chen, Xiaohui; Hu, Chaosu

2014-01-01

To analyze patterns of local-regional failure after primary intensity modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). A total of 370 non-metastatic NPC patients consecutively treated with IMRT (with or without chemotherapy) were analyzed. Radiotherapy was administered using a simultaneous integrated boost (SIB) technique at the total prescribed dose of 66-70.4Gy (2.0-2.2Gy per fraction). The location and extent of local-regional failures were transferred to the pretreatment planning computed tomography (CT) for dosimetric analysis. The dose of radiation received by V recur (volume of recurrence) was calculated and analyzed with dose-volume histogram (DVH). Failures were classified as: 'in field' if 95% of V recur was within the 95% isodose, 'marginal' if 20% to 95% of V recur was within the 95% isodose, or 'outside' if less than 20% of V recur was inside the 95% isodose. With a median follow up of 26 months, 25 local-regional failures were found in 18 patients. The 1- and 2-year actuarial local-regional control rates for all patients were 99.7% and 95.5% respectively. Among the 22 local–regional failures with available diagnostic images, 16 (64%) occurred within the 95% isodose lines and were considered in-field failures; 3 (12%) were marginal and 3 (12%) were outside-field failures. Intensity-modulated radiotherapy provides excellent local-regional control for NPC. In-field failures are the main patterns for local-regional recurrence. Reducing the coverage of critical adjacent tissues in CTV purposefully for potential subclinical diseases was worth of study. Great attention in all IMRT steps is necessary to reduce potential causes of marginal failures. More studies about radioresistance are needed to reduce in-field failures

SU-E-T-809: Volumetric Modulated Arc Radiotherapy Vs. Intensity-Modulated Radiotherapy for Locally Advanced Laryngeal Carcinoma: A Dosimetric Study

Energy Technology Data Exchange (ETDEWEB)

Lu, J-Y; Huang, B-T; Zhang, W-Z; Yan, L-J [Cancer Hospital of Shantou University Medical College, Shantou, Guangdong (China)

2015-06-15

Purpose: To compare volumetric modulated arc radiotherapy (VMAT) technique with fixed-gantry intensity-modulated radiotherapy (IMRT) technique for locally advanced laryngeal carcinoma. Methods: CT datasets of eleven patients were included. Dual-arc VMAT and 7-field IMRT plans, which were created based on the Eclipse treatment planning system, were compared in terms of dose-volume parameters, conformity index (CI) and homogeneity index (HI) of planning target volume (PTV), as well as organ-at-risk (OAR) sparing, planning time, monitor units (MUs) and delivery time. Results: Compared with the IMRT plans, the VMAT plans provided lower D2% and better CI/HI for the high-risk PTV (PTV1), and provided better CI and comparable HI for the low-risk PTV (PTV2). Concerning the OAR sparing, the VMAT plans demonstrated significantly lower Dmax of the spinal cord (planning OAR volume, PRV) and brainstem (PRV), as well as lower Dmean and V30Gy of the right parotid. No significant differences were observed between the two plans concerning the doses delivered to the thyroid, carotid, oral cavity and left parotid. Moreover, the VMAT planning (147 ± 18 min) consumed 213% more time than the IMRT planning (48 ± 10 min). The MUs of the VMAT plans (556 ± 52) were 64% less than those of the IMRT plans (1684 ± 409), and the average delivery time (2.1 ± 0.1 min) was 66% less than that of the IMRT plans (6.3 ± 0.7 min). Conclusion: Compared with the IMRT technique, the VMAT technique can achieve superior target dose distribution and better sparing of the spinal cord, brainstem and right parotid, with less MUs and less delivery time. It is recommended for the radiotherapy of locally advanced laryngeal carcinoma.

Intensity-Modulated Radiotherapy versus 3-Dimensional Conformal Radiotherapy Strategies for Locally Advanced Non-Small-Cell Lung Cancer

Directory of Open Access Journals (Sweden)

Uğur Selek

2014-12-01

Full Text Available Chemoradiotherapy is the current standard of care in patients with advanced inoperable stage IIIA or IIIB non-small cell lung cancer (NSCLC. Three-dimensional radiotherapy (3DCRT has been a trusted method for a long time and has well-known drawbacks, most of which could be improved by Intensity Modulated Radiotherapy (IMRT. IMRT is not currently the standard treatment of locally advanced NSCLC, but almost all patients could benefit to a degree in organ at risk sparing, dose coverage conformality, or dose escalation. The most critical step for a radiation oncology department is to strictly evaluate its own technical and physical capabilities to determine the ability of IMRT to deliver an optimal treatment plan. This includes calculating the internal tumor motion (ideally 4DCT or equivalent techniques, treatment planning software with an up-to-date heterogeneity correction algorithm, and daily image guidance. It is crucial to optimise and individualise the therapeutic ratio for each patient during the decision of 3DCRT versus IMRT. The current literature rationalises the increasing use of IMRT, including 4D imaging plus PET/CT, and encourages the applicable knowledge-based and individualised dose escalation using advanced daily image-guided radiotherapy.

'Tongue-and-groove' effect in intensity modulated radiotherapy with static multileaf collimator fields

International Nuclear Information System (INIS)

Que, W; Kung, J; Dai, J

2004-01-01

The 'tongue-and-groove problem' in step-and-shoot delivery of intensity modulated radiotherapy is investigated. A 'tongue-and-groove' index (TGI) is introduced to quantify the 'tongue-and-groove' effect in step-and-shoot delivery. Four different types of leaf sequencing methods are compared. The sliding window method and the reducing level method use the same number of field segments to deliver the same intensity map, but the TGI is much less for the reducing level method. The leaf synchronization method of Van Santvoort and Heijmen fails in step-and-shoot delivery, but a new method inspired by the method of Van Santvoort and Heijmen is shown to eliminate 'tongue-and-groove' underdosage completely

Chemotherapy and intensity modulated conformational radiotherapy for locally advanced pancreas cancers; Chimiotherapie et radiotherapie conformationnelle avec modulation d'intensite pour les cancers du pancreas localement evolues

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Huguet, F. [Hopital Tenon, Paris (France); Wu, A.; Zhang, Z.; Winston, C.; Reidy, D.; Ho, A.; Allen, P.; Karyn, G. [Memorial Sloan-Kettering Cancer Center, New York (United States)

2011-10-15

The authors report a retrospective study of the tolerance and survival of 48 patients who have been treated by a chemotherapy followed by a chemotherapy concomitant with an intensity-modulated radiotherapy for a locally advanced pancreas cancer. Results are discussed in terms of toxicity, cancer response, operability, survival rate. Tolerance is good. Local control rates, global survival rates and secondary resection rates are promising. Short communication

Application of a hydrogel spacer for postoperative salvage radiotherapy of prostate cancer

International Nuclear Information System (INIS)

Pinkawa, Michael; Schubert, Carolin; Escobar-Corral, Nuria; Holy, Richard; Eble, Michael J.

2015-01-01

In contrast to primary radiotherapy, no reports are available for a hydrogel spacer application in postoperative salvage radiotherapy for prostate cancer. A 77-year-old patient presented 20 years after radical prostatectomy with a digitally palpable local recurrence at the urethrovesical anastomosis (PSA 5.5 ng/ml). The hydrogel spacer (10 ml, SpaceOAR trademark) was injected between the local recurrence and rectal wall under transrectal ultrasound guidance. Treatment planning was performed with an intensity-modulated technique up to a total dose of 76 Gy in 2-Gy fractions. The same planning was performed based on computed tomography before spacer injection for comparison. The local recurrence, initially directly on the rectal wall, could be displaced more than 1 cm from the rectal wall after hydrogel injection. With a mean total dose of 76 Gy to the planning target volume, rectal wall volumes included in the 70 Gy, 60 Gy, 50 Gy isodoses were 0 cm 3 , 0 cm 3 , and 0.4 cm 3 with a spacer and 2.9 cm 3 , 4.5 cm 3 , and 6.2 cm 3 without a spacer, respectively. The patient reported rectal urgency during radiotherapy, completely resolving after the end of treatment. The PSA level was 5.4 ng/ml a week before the end of radiotherapy and dropped to 0.9 ng/ml 5 months after radiotherapy. A hydrogel spacer was successfully applied for dose-escalated radiotherapy in a patient with macroscopic local prostate cancer recurrence at the urethrovesical anastomosis to decrease the dose at the rectal wall. This option can be considered in specifically selected patients. (orig.) [de

Stereotactic Image-Guided Intensity Modulated Radiotherapy Using the HI-ART II Helical Tomotherapy System

International Nuclear Information System (INIS)

Holmes, Timothy W.; Hudes, Richard; Dziuba, Sylwester; Kazi, Abdul; Hall, Mark; Dawson, Dana

2008-01-01

The highly integrated adaptive radiation therapy (HI-ART II) helical tomotherapy unit is a new radiotherapy machine designed to achieve highly precise and accurate treatments at all body sites. The precision and accuracy of the HI-ART II is similar to that provided by stereotactic radiosurgery systems, hence the historical distinction between external beam radiotherapy and stereotactic procedures based on differing precision requirements is removed for this device. The objectives of this work are: (1) to describe stereotactic helical tomotherapy processes (SRS, SBRT); (2) to show that the precision and accuracy of the HI-ART meet the requirements defined for SRS and SBRT; and (3) to describe the clinical implementation of a stereotactic image-guided intensity modulated radiation therapy (IG-IMRT) system that incorporates optical motion management

Dosimetric comparison of field in field intensity-modulated radiotherapy technique with conformal radiotherapy techniques in breast cancer

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Ercan, T.; Alco, G.; Zengin, F.; Atilla, S.; Dincer, M.; Igdem, S.; Okkan, S.

2010-01-01

The aim of this study was to be able to implement the field-in-field intensity-modulated radiotherapy (FiF) technique in our daily practice for breast radiotherapy. To do this, we performed a dosimetric comparison. Treatment plans were produced for 20 consecutive patients. FiF plans and conformal radiotherapy (CRT) plans were compared for doses in the planning target volume (PTV), the dose homogeneity index (DHI), doses in irradiated soft tissue outside the target volume (SST), ipsilateral lung and heart doses for left breast irradiation, and the monitor unit counts (MU) required for treatment. Averaged values were compared using Student's t-test. With FiF, the DHI is improved 7.0% and 5.7%, respectively (P<0.0001) over the bilateral and lateral wedge CRT techniques. When the targeted volumes received 105% and 110% of the prescribed dose in the PTV were compared, significant decreases are found with the FiF technique. With the 105% dose, the SST, heart, and ipsilateral lung doses and the MU counts were also significantly lower with the FiF technique. The FiF technique, compared to CRT, for breast radiotherapy enables significantly better dose distribution in the PTV. Significant differences are also found for soft tissue volume, the ipsilateral lung dose, and the heart dose. Considering the decreased MUs needed for treatment, the FiF technique is preferred over tangential CRT. (author)

Bladder radiotherapy treatment: A retrospective comparison of 3-dimensional conformal radiotherapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy plans

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Pasciuti, Katia, E-mail: k.pasciuti@virgilio.it [Department of Radiotherapy Physics, Royal Free Hospital, London (United Kingdom); Kuthpady, Shrinivas [Department of Radiotherapy, Royal Free Hospital, London (United Kingdom); Anderson, Anne; Best, Bronagh [Department of Radiotherapy Physics, Royal Free Hospital, London (United Kingdom); Waqar, Saleem; Chowdhury, Subhra [Department of Radiotherapy, Royal Free Hospital, London (United Kingdom)

2017-04-01

To examine tumor's and organ's response when different radiotherapy plan techniques are used. Ten patients with confirmed bladder tumors were first treated using 3-dimensional conformal radiotherapy (3DCRT) and subsequently the original plans were re-optimized using the intensity-modulated radiation treatment (IMRT) and volumetric-modulated arc therapy (VMAT)-techniques. Targets coverage in terms of conformity and homogeneity index, TCP, and organs' dose limits, including integral dose analysis were evaluated. In addition, MUs and treatment delivery times were compared. Better minimum target coverage (1.3%) was observed in VMAT plans when compared to 3DCRT and IMRT ones confirmed by a statistically significant conformity index (CI) results. Large differences were observed among techniques in integral dose results of the femoral heads. Even if no statistically significant differences were reported in rectum and tissue, a large amount of energy deposition was observed in 3DCRT plans. In any case, VMAT plans provided better organs and tissue sparing confirmed also by the normal tissue complication probability (NTCP) analysis as well as a better tumor control probability (TCP) result. Our analysis showed better overall results in planning using VMAT techniques. Furthermore, a total time reduction in treatment observed among techniques including gantry and collimator rotation could encourage using the more recent one, reducing target movements and patient discomfort.

Treatment-Planning Study of Prostate Cancer Intensity-Modulated Radiotherapy With a Varian Clinac Operated Without a Flattening Filter

International Nuclear Information System (INIS)

Vassiliev, Oleg N.; Kry, Stephen F.; Kuban, Deborah A.; Salehpour, Mohammad; Mohan, Radhe; Titt, Uwe

2007-01-01

Purpose: To assess the feasibility of intensity-modulated radiotherapy for prostate cancer using photon beams from an accelerator operated without a flattening filter; and to determine potential benefits and drawbacks of using unflattened beams for this type of treatment. Methods and Materials: Intensity-modulated radiotherapy plans were generated for 10 patients with early-stage prostate cancer. For each patient, four plans were generated: with and without the flattening filter, at 6 and 18 MV. The prescription dose was 75.6 Gy to 98% of the planning target volume. The number of beams, their orientations, and optimization constraints were the same for all plans. Plans were generated with Eclipse 8.0 (Varian Medical Systems). Results: All the plans developed with unflattened beams were clinically acceptable. In terms of patient dose distributions, plans with unflattened beams were similar to the corresponding plans with flattened beams. Plans with unflattened beams required fewer monitor units (MUs) per plan: on average, by a factor of 2.0 at 6 MV and 2.6 at 18 MV, assuming that removal of the flattening filter was not followed by recalibration of MUs. Conclusions: Clinically acceptable intensity-modulated radiotherapy plans for prostate cancer can be developed with unflattened beams at both 6 and 18 MV. Dosimetrically, flattened and unflattened beams generated similar treatment plans. The plans with unflattened beams required substantially fewer MUs. The reduction in the number of MUs indicates corresponding reduction in beam-on time and in the amount of radiation outside the target

Postoperative Intensity Modulated Radiation Therapy in High Risk Prostate Cancer: A Dosimetric Comparison

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Digesu, Cinzia; Cilla, Savino; De Gaetano, Andrea; Massaccesi, Mariangela; Macchia, Gabriella; Ippolito, Edy; Deodato, Francesco; Panunzi, Simona; Iapalucci, Chiara; Mattiucci, Gian Carlo; D'Angelo, Elisa; Padula, Gilbert D.A.; Valentini, Vincenzo; Cellini, Numa

2011-01-01

The aim of this study was to compare intensity-modulated radiation therapy (IMRT) with 3D conformal technique (3D-CRT), with respect to target coverage and irradiation of organs at risk for high dose postoperative radiotherapy (PORT) of the prostate fossa. 3D-CRT and IMRT treatment plans were compared with respect to dose to the rectum and bladder. The dosimetric comparison was carried out in 15 patients considering 2 different scenarios: (1) exclusive prostate fossa irradiation, and (2) pelvic node irradiation followed by a boost on the prostate fossa. In scenario (1), a 3D-CRT plan (box technique) and an IMRT plan were calculated and compared for each patient. In scenario (2), 3 treatment plans were calculated and compared for each patient: (a) 3D-CRT box technique for both pelvic (prophylactic nodal irradiation) and prostate fossa irradiation (3D-CRT only); (b) 3D-CRT box technique for pelvic irradiation followed by an IMRT boost to the prostatic fossa (hybrid 3D-CRT and IMRT); and (c) IMRT for both pelvic and prostate fossa irradiation (IMRT only). For exclusive prostate fossa irradiation, IMRT significantly reduced the dose to the rectum (lower Dmean, V50%, V75%, V90%, V100%, EUD, and NTCP) and the bladder (lower Dmean, V50%, V90%, EUD and NTCP). When prophylactic irradiation of the pelvis was also considered, plan C (IMRT only) performed better than plan B (hybrid 3D-CRT and IMRT) as respect to both rectum and bladder irradiation (reduction of Dmean, V50%, V75%, V90%, equivalent uniform dose [EUD], and normal tissue complication probability [NTCP]). Plan (b) (hybrid 3D-CRT and IMRT) performed better than plan (a) (3D-CRT only) with respect to dose to the rectum (lower Dmean, V75%, V90%, V100%, EUD, and NTCP) and the bladder (Dmean, EUD, and NTCP). Postoperative IMRT in prostate cancer significantly reduces rectum and bladder irradiation compared with 3D-CRT.

Dose determination in radiotherapy for photon beams modified by static intensity modulators

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Castellanos Lopez, M.E.

1998-01-01

The static intensity modulators, used in radiotherapy, modify the spectral composition of the beam and lead to specific problems of the dose calculation. The aim of this work was to establish a three dimensional calculation, global and accurate, adapted to the primary-diffused separation algorithm and valid for any static modulator type. A theoretical study, experimentally verified, allowed the evaluation of the primary fluence, resulting from metallic sheets placed between photons beams of 6 to 23 MV nominal energy. It has been showed that the diffused, coming from the modulators, could be neglected for weak thickness and for the relative dose variation. In return it leads to significant variations of many % on the absolute dose and must be take into account for the bigger thicknesses. Corrective methods for the primary fluence have been proposed. From the energy spectra of the beam, the metallic modulator influence has been studied on the primary and diffused components of the dose and improvements of the calculation method have been proposed. These improvements are based on the modulator representation as a transmission matrix and on semi-empirical corrective factors. (A.L.B.)

Dosimetric aspects of breast radiotherapy with three-dimensional and intensity-modulated radiotherapy helical tomotherapy planning modules

International Nuclear Information System (INIS)

Yadav, Poonam; Yan, Yue; Ignatowski, Tasha; Olson, Anna

2017-01-01

In this work, we investigated the dosimetric differences between the intensity-modulated radiotherapy (IMRT) plans and the three-dimensional (3D) helical plans based on the TomoTherapy system. A total of 15 patients with supine setup were randomly selected from the data base. For patients with lumpectomy planning target volume (PTV), regional lymph nodes were also included as part of the target. For dose sparing, the significant differences between the helical IMRT and helical 3D were only found in the heart and contralateral breast. For the dose to the heart, helical IMRT reduced the maximum point dose by 6.98 Gy compared to the helical 3D plan (p = 0.01). For contralateral breast, the helical IMRT plans significantly reduced the maximum point dose by 5.6 Gy compared to the helical 3D plan. However, compared to the helical 3D plan, the helical IMRT plan increased the volume for lower dose (13.08% increase in V 5 Gy , p = 0.01). In general, there are no significant differences in dose sparing between helical IMRT and helical 3D plans.

Magnetic Resonance-Based Treatment Planning for Prostate Intensity-Modulated Radiotherapy: Creation of Digitally Reconstructed Radiographs

International Nuclear Information System (INIS)

Chen, Lili; Nguyen, Thai-Binh; Jones, Elan; Chen Zuoqun; Luo Wei; Wang Lu; Price, Robert A.; Pollack, Alan; Ma, C.-M. Charlie

2007-01-01

Purpose: To develop a technique to create magnetic resonance (MR)-based digitally reconstructed radiographs (DRR) for initial patient setup for routine clinical applications of MR-based treatment planning for prostate intensity-modulated radiotherapy. Methods and Materials: Twenty prostate cancer patients' computed tomography (CT) and MR images were used for the study. Computed tomography and MR images were fused. The pelvic bony structures, including femoral heads, pubic rami, ischium, and ischial tuberosity, that are relevant for routine clinical patient setup were manually contoured on axial MR images. The contoured bony structures were then assigned a bulk density of 2.0 g/cm 3 . The MR-based DRRs were generated. The accuracy of the MR-based DDRs was quantitatively evaluated by comparing MR-based DRRs with CT-based DRRs for these patients. For each patient, eight measuring points on both coronal and sagittal DRRs were used for quantitative evaluation. Results: The maximum difference in the mean values of these measurement points was 1.3 ± 1.6 mm, and the maximum difference in absolute positions was within 3 mm for the 20 patients investigated. Conclusions: Magnetic resonance-based DRRs are comparable to CT-based DRRs for prostate intensity-modulated radiotherapy and can be used for patient treatment setup when MR-based treatment planning is applied clinically

Prospective Trial of High-Dose Reirradiation Using Daily Image Guidance With Intensity-Modulated Radiotherapy for Recurrent and Second Primary Head-and-Neck Cancer

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Chen, Allen M.; Farwell, D. Gregory; Luu, Quang; Cheng, Suzan; Donald, Paul J.; Purdy, James A.

2011-01-01

Purpose: To report a single-institutional experience using intensity-modulated radiotherapy with daily image-guided radiotherapy for the reirradiation of recurrent and second cancers of the head and neck. Methods and Materials: Twenty-one consecutive patients were prospectively treated with intensity-modulated radiotherapy from February 2006 to March 2009 to a median dose of 66 Gy (range, 60-70 Gy). None of these patients received concurrent chemotherapy. Daily helical megavoltage CT scans were obtained before each fraction as part of an image-guided radiotherapy registration protocol for patient alignment. Results: The 1- and 2-year estimates of in-field control were 72% and 65%, respectively. A total of 651 daily megavoltage CT scans were obtained. The mean systematic shift to account for interfraction motion was 1.38 ± 1.25 mm, 1.79 ± 1.45 mm, and 1.98 ± 1.75 mm for the medial-lateral, superior-inferior, and anterior-posterior directions, respectively. Pretreatment shifts of >3 mm occurred in 19% of setups in the medial-lateral, 27% in the superior-inferior, and 33% in the anterior-posterior directions, respectively. There were no treatment-related fatalities or hospitalizations. Complications included skin desquamation, odynophagia, otitis externa, keratitis, naso-lacrimal duct stenosis, and brachial plexopathy. Conclusions: Intensity-modulated radiotherapy with daily image guidance results in effective disease control with relatively low morbidity and should be considered for selected patients with recurrent and second primary cancers of the head and neck.

Intensity-Modulated Radiotherapy for Oral Cavity Squamous Cell Carcinoma: Patterns of Failure and Predictors of Local Control

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Daly, Megan E.; Le, Quynh-Thu; Kozak, Margaret M.; Maxim, Peter G.; Murphy, James D.; Hsu, Annie; Loo, Billy W.; Kaplan, Michael J.; Fischbein, Nancy J.; Chang, Daniel T.

2011-01-01

Purpose: Few studies have evaluated the use of intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma (SCC) of the oral cavity (OC). We report clinical outcomes and failure patterns for these patients. Methods and Materials: Between October 2002 and June 2009, 37 patients with newly diagnosed SCC of the OC underwent postoperative (30) or definitive (7) IMRT. Twenty-five patients (66%) received systemic therapy. The median follow-up was 38 months (range, 10-87 months). The median interval from surgery to RT was 5.9 weeks (range, 2.1-10.7 weeks). Results: Thirteen patients experienced local-regional failure at a median of 8.1 months (range, 2.4-31.9 months), and 2 additional patients experienced local recurrence between surgery and RT. Seven local failures occurred in-field (one with simultaneous nodal and distant disease) and two at the margin. Four regional failures occurred, two in-field and two out-of-field, one with synchronous metastases. Six patients experienced distant failure. The 3-year actuarial estimates of local control, local-regional control, freedom from distant metastasis, and overall survival were 67%, 53%, 81%, and 60% among postoperative patients, respectively, and 60%, 60%, 71%, and 57% among definitive patients. Four patients developed Grade ≥2 chronic toxicity. Increased surgery to RT interval predicted for decreased LRC (p = 0.04). Conclusions: Local-regional control for SCC of the OC treated with IMRT with or without surgery remains unsatisfactory. Definitive and postoperative IMRT have favorable toxicity profiles. A surgery-to-RT interval of <6 weeks improves local-regional control. The predominant failure pattern was local, suggesting that both improvements in target delineation and radiosensitization and/or dose escalation are needed.

Intensity modulated radiotherapy (IMRT) for pediatric cancer patients: The advantage and fear of second malignant neoplasm

International Nuclear Information System (INIS)

Zaghloul, M.S.

2013-01-01

Intensity-modulated radiotherapy is used for delivering more efficient homogenous dose to the target and lowering of dose to the surrounding normal tissues. However, a second malignant neoplasm may develop after prolonged latent period. The use of modern precise radiotherapy techniques in the pediatric age group has many controversial issues in spite of its proven dosimetric distribution advantages and the considerable decrease of normal tissue complication probability (NTCP). This concern is due to many factors; mainly the exposure of a larger volume of normal tissues to low dose radiotherapy. Children have more proliferating tissues compared to the adults. However, the epidemiological data did not detect an increase in the incidence of radiation-induced second malignancy. This issue is still controversial as IMRT and other precise radiotherapy techniques were not widely used except recently. This may entail a thorough careful follow up for children treated with these techniques to detect any incidence increase

The Role of Postoperative Radiotherapy in the Management of Intracranial Meningiomas

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Chang, Sei Kyung; Suh, Chang Ok; Shin, Hyun Soo; Kim, Gwi Eon

1994-01-01

Purpose: To evaluate the role of postoperative radiotherapy in the management of primary or recurrent intracranial meningiomas. Methods and Materials: A retrospective review of 34 intracranial meningioma patients referred to the Yonsei Cancer Center for postoperative radiotherapy between 1981 and 1990 was undertaken. Of the 34 patients, 24 patients received elective postoperative radiotherapy after total or subtotal resection(Group 1), and 10 patients received postoperative radiotherapy as a salvage treatment for recurrent tumors(Group 2). Ten patients received postoperative radiotherapy after total resection, and twenty-four after subtotal resection. Ten patients who had total tumor resection were referred for radiotherapy either because of angioblastic or malignant histologic type (4 patients in Group 1) or because of recurrent disease after initial surgery(6 patients in Group 2). Radiation dose of 50-56Gy was delivered over a period of 5-5.5 weeks using 4MV LINAC or Co-60 teletherapy unit. Results: Overall actuarial progression free survival (PFS) at 5 years was 80%. Survival was most likely affected by histologic subtypes. Five year PFS rate was 52% for benign angioblastic histology, as compared with 100% for classic benign histology. For malignant meningiomas, 5 year PFS rate was 44%. The recurrence rates of classic, angioblastic, and malignant type were 5%(1/21), 80%(4/5), and 50%(4/8), respectively. The duration between salvage post-operative radiotherapy and recurrence was longer than the duration between initial surgery and recurrence in the patients of group 2 with angioblastic or malignant histology. Conclusion: Postoperative radiotherapy of primary or recurrent intracranial meningiomas appears to be effective modality, especially in the patients with classic meningiomas. In angioblastic or malignant histologies, a more effective approach seems to be needed for decreasing recurrence rate

Intensity modulated radiotherapy for sinonasal malignancies with a focus on optic pathway preservation

Directory of Open Access Journals (Sweden)

Chi Alexander

2013-01-01

Full Text Available Abstract Purpose To assess if intensity-modulated radiotherapy (IMRT can possibly lead to improved local control and lower incidence of vision impairment/blindness in comparison to non-IMRT techniques when treating sinonasal malignancies; what is the most optimal dose constraints for the optic pathway; and the impact of different IMRT strategies on optic pathway sparing in this setting. Methods and materials A literature search in the PubMed databases was conducted in July, 2012. Results Clinical studies on IMRT and 2D/3D (2 dimensional/3 dimensional RT for sinonasal malignancies suggest improved local control and lower incidence of severe vision impairment with IMRT in comparison to non-IMRT techniques. As observed in the non-IMRT studies, blindness due to disease progression may occur despite a lack of severe toxicity possibly due to the difficulty of controlling locally very advanced disease with a dose ≤ 70 Gy. Concurrent chemotherapy’s influence on the the risk of severe optic toxicity after radiotherapy is unclear. A maximum dose of ≤ 54 Gy with conventional fractionation to the optic pathway may decrease the risk of blindness. Increased magnitude of intensity modulation through increasing the number of segments, beams, and using a combination of coplanar and non-coplanar arrangements may help increase dose conformality and optic pathway sparing when IMRT is used. Conclusion IMRT optimized with appropriate strategies may be the treatment of choice for the most optimal local control and optic pathway sparing when treating sinonasal malignancy.

Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer

International Nuclear Information System (INIS)

Shirvani, Shervin M.; Komaki, Ritsuko; Heymach, John V.; Fossella, Frank V.; Chang, Joe Y.

2012-01-01

Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non–small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39–86). The median follow-up duration was 21 months (range, 4–58) in all patients and 26 months (range, 4–58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive

Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer

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Shirvani, Shervin M.; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Heymach, John V.; Fossella, Frank V. [Department of Thoracic/Head and Neck Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

2012-01-01

Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non-small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39-86). The median follow-up duration was 21 months (range, 4-58) in all patients and 26 months (range, 4-58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive intensity-modulated

Contribution of PET and PET/CT in CTV/PTV-modulation for planning of intensity modulated radiotherapy (IMRT)

International Nuclear Information System (INIS)

Oehler, W.; Baum, R.P.

2004-01-01

PET and PET/CT enlarge the possibilities of purely anatomic imaging by opening up new horizons in determining the metabolic and molecular properties of tumors. This enables to determine the spread of tumors with higher accuracy, especially concerning the primary staging and the diagnosis of recurrences. Patients with locoregional disease which are curable by surgery or local radiotherapy (eventually in combination with chemotherapy) can be differentiated from those patients, where only palliative treatment is indicated. Novel nuclear medicine procedures, which use specific tracers, open the door for the molecular treatment of tumors. This will be especially important for radiation oncology. In future it will be possible to define specific tumor areas within a morphologically homogeneous tumor (e.g. areas of tumor hypoxia, increased local tumor stem cell concentration, tumor parts with higher proliferative activity etc.). With IMRT (intensity modulated radiotherapy) we have already now the opportunity, to concentrate the dose to these specific tumor areas, without overloading normal tissues and organs at risk. (orig.)

Efficacy of post-operative radiotherapy in the treatment of breast cancer

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Api, P; Corcione, S; Magnoni, G

1985-01-01

A clinical evaluation regarding the efficacy of post-operative radiotherapy in 294 patients with breast cancer is presented. In the author's opinion post-operative radiotherapy is fundamental in the treatment of this tumor. 21 refs.

Spinal cordd biological safety comparison of intensity modulated radiotherapy and conventional radiation therapy

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Xilinbaoleri; Xu Wanlong; Chen Gang; Liu Hao; Wang Ruozheng; Bai Jingping

2010-01-01

Objective: To compare the spine intensity modulated radiation therapy (IMRT) and the conventional radiation therapy on the beagle spinal cord neurons, in order to prove the biological safety of IMRT of the spinal cord. Methods: Twelve selected purebred beagles were randomly divided into 2 groups. A beagle clinical model of tumor was mimiced in the ninth and tenth thoracic vertebrae. Then the beagles were irradiated by 2 different models of intensity modulated radiotherapy and conventional radiation therapy, with the total irradiation doses of 50 and 70 Gy. The samples of spinal cord were taken out from the same position of the nine and tenth thoracic vertebrae at the third month after radiation.All the samples were observed by the electron microscope, and the Fas and HSP70 expression in spinal cord neurons were evaluated by immunohistochemistry method. Terminal deoxynucleatidyl transferase mediated dUTP nick and labeling (TUNEL) technique was used to examine the apoptotic cells in the spinal cord. Results: The neurons in the spinal cord of IMRT group were mainly reversible injury, and those in the conventional radiation therapy were mainly apoptosis. Compared with the conventional radiation therapy group [50 Gy group, (7.3 ± 1.1)%; 70 Gy group, (11.3 ± 1.4)%], the apoptosis rate of the spinal cord neurons of the intensity modulated radiotherapy group [50 Gy group, (1.2 ± 0.7)%; 70 Gy group (2.5 ± 0.8)%] was much lower[(50 Gy group, t=0.022, P<0.05; 70 Gy group, t=0.017, P<0.05)]. The expression levels of Fas in the IMPT group (50 Gy group, 4.6 ± 0.8; 70 Gy group, 7.4 ± 1.1) were also much lowerthan those in the other group (50 Gy group, 15.1 ± 6.4; 70 Gy group, 19.3 ± 7.6. 50 Gy group, t=0.231, P<0.05; 70 Gy group, t=0.457, P<0.05), while the expression levels of HSP70 in the IMPT group (50 Gy group, 9.1 ± 0.8; 70 Gy group, 7.3 ± 1.4)were much higher than those in the conventional radiation therapy group (50 Gy group, 2.1 ± 0.9; 70 Gy group, 1.7 ± 0

Intensity Modulated Neutron Radiotherapy for the Treatment of Adenocarcinoma of the Prostate

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Santanam, Lakshmi; He, Tony; Yudelev, Mark; Forman, Jeffrey D.; Orton, Colin G.; Heuvel, Frank van den; Maughan, Richard L.; Burmeister, Jay

2007-01-01

Purpose: This study investigates the enhanced conformality of neutron dose distributions obtainable through the application of intensity modulated neutron radiotherapy (IMNRT) to the treatment of prostate adenocarcinoma. Methods and Materials: An in-house algorithm was used to optimize individual segments for IMNRT generated using an organ-at-risk (OAR) avoidance approach. A number of beam orientation schemes were investigated in an attempt to approach an optimum solution. The IMNRT plans were created retrospectively for 5 patients previously treated for prostate adenocarcinoma using fast neutron therapy (FNT), and a comparison of these plans is presented. Dose distributions and dose-volume histograms (DVHs) were analyzed and plans were evaluated based on percentage volumes of rectum and bladder receiving 95%, 80%, and 50% (V 95 , V 80 , V 50 ) of the prescription dose, and on V 60 for both the femoral heads and GM muscle group. Results: Plans were normalized such that the IMNRT DVHs for prostate and seminal vesicles were nearly identical to those for conventional FNT plans. Use of IMNRT provided reductions in rectum V 95 and V 80 of 10% (2-27%) and 13% (5-28%), respectively, and reductions in bladder V 95 and V 80 of 12% (3-26%) and 4% (7-10%), respectively. The average decrease in V 60 for the femoral heads was 4.5% (1-18%), with no significant change in V 60 for the GM muscle group. Conclusions: This study provides the first analysis of the application of intensity modulation to neutron radiotherapy. The IMNRT technique provides a substantial reduction in normal tissue dose in the treatment of prostate cancer. This reduction should result in a significant clinical advantage for this and other treatment sites

Locally Advanced Oncocytic Carcinoma of the Nasal Cavity Treated With Surgery and Intensity-modulated Radiotherapy

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Yu-Wen Hu

2010-03-01

Full Text Available Oncocytic carcinomas of the nasal cavity are extremely rare. We report 1 patient whose primary tumor and neck lymphadenopathies were under control nearly 2 years after combined surgery and radiotherapy. An 80-year-old man with a history of nasal oncocytoma had received excision twice previously. Computed tomography demonstrated locally advanced recurrent tumor invading the paranasal sinuses and orbit with lymphadenopathies in the right neck. Skull base surgery was performed. Pathological examination revealed oncocytic carcinoma. Positron emission tomography showed hypermetabolic lesions in the surgical bed and right neck. The patient subsequently received intensity-modulated radiotherapy to the primary site and the whole neck. Follow-up computed tomography 4 months later showed marked shrinkage of the neck lymphadenopathies. There was no progression after nearly 2 years. Although these tumors have historically been regarded as radioresistant, the combined treatment of surgery followed by radiotherapy may offer the best chance for control of locally advanced disease.

A dosimetric comparison of two-phase adaptive intensity-modulated radiotherapy for locally advanced nasopharyngeal cancer

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Chitapanarux, Imjai; Chomprasert, Kittisak; Nobnaop, Wannapa; Wanwilairat, Somsak; Tharavichitkul, Ekasit; Jakrabhandu, Somvilai; Onchan, Wimrak; Traisathit, Patrinee; Van Gestel, Dirk

2015-01-01

The purpose of this investigation was to evaluate the potential dosimetric benefits of a two-phase adaptive intensity-modulated radiotherapy (IMRT) protocol for patients with locally advanced nasopharyngeal cancer (NPC). A total of 17 patients with locally advanced NPC treated with IMRT had a second computed tomography (CT) scan after 17 fractions in order to apply and continue the treatment with an adapted plan after 20 fractions. To simulate the situation without adaptation, a hybrid plan w...

The Failure Patterns of Oral Cavity Squamous Cell Carcinoma After Intensity-Modulated Radiotherapy-University of Iowa Experience

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Yao Min; Chang, Kristi; Funk, Gerry F.; Lu Heming; Tan Huaming; Wacha, Judith C; Dornfeld, Kenneth J.; Buatti, John M.

2007-01-01

Purpose: Determine the failure patterns of oral cavity squamous cell carcinoma (SCC) treated with intensity-modulated radiotherapy (IMRT). Methods and Materials: Between May 2001 and July 2005, 55 patients with oral cavity SCC were treated with IMRT for curative intent. Forty-nine received postoperative IMRT, 5 definitive IMRT, and 1 neoadjuvant. Three target volumes were defined (clinical target CTV1, CTV2, and CTV3). The failure patterns were determined by coregistration or comparison of the treatment planning computed tomography to the images obtained at the time of recurrence. Results: The median follow-up for all patients was 17.1 months (range, 0.27-59.3 months). The median follow-up for living patients was 23.9 months (range, 9.3-59.3 months). Nine patients had locoregional failures: 4 local failures only, 2 regional failures only, and 3 had both local and regional failures. Five patients failed distantly; of these, 3 also had locoregional failures. The 2-year overall survival, disease-specific survival, local recurrence-free survival, locoregional recurrence-free survival, and distant disease-free survival was 68%, 74%, 85%, 82%, and 89%, respectively. The median time from treatment completion to locoregional recurrence was 4.1 months (range, 3.0-12.1 months). Except for 1 patient who failed in contralateral lower neck outside the radiation field, all failed in areas that had received a high dose of radiation. The locoregional control is strongly correlated with extracapsular extension. Conclusions: Intensity-modulated RT is effective for oral cavity SCC. Most failures are in-field failures. Further clinical studies are necessary to improve the outcomes of patients with high-risk features, particularly for those with extracapsular extension

Retrospective evaluation of dosimetric quality for prostate carcinomas treated with 3D conformal, intensity modulated and volumetric modulated arc radiotherapy

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Crowe, Scott B [Science and Engineering Faculty, Queensland University of Technology, Brisbane, Queensland (Australia); Kairn, Tanya [Science and Engineering Faculty, Queensland University of Technology, Brisbane, Queensland (Australia); Premion, Wesley Medical Centre, Brisbane, Queensland (Australia); Middlebrook, Nigel; Hill, Brendan; Christie, David R H; Knight, Richard T [Premion, Wesley Medical Centre, Brisbane, Queensland (Australia); Kenny, John [Australian Clinical Dosimetry Services, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Victoria (Australia); Langton, Christian M; Trapp, Jamie V [Science and Engineering Faculty, Queensland University of Technology, Brisbane, Queensland (Australia)

2013-12-15

This study examines and compares the dosimetric quality of radiotherapy treatment plans for prostate carcinoma across a cohort of 163 patients treated across five centres: 83 treated with three-dimensional conformal radiotherapy (3DCRT), 33 treated with intensity modulated radiotherapy (IMRT) and 47 treated with volumetric modulated arc therapy (VMAT). Treatment plan quality was evaluated in terms of target dose homogeneity and organs at risk (OAR), through the use of a set of dose metrics. These included the mean, maximum and minimum doses; the homogeneity and conformity indices for the target volumes; and a selection of dose coverage values that were relevant to each OAR. Statistical significance was evaluated using two-tailed Welch's T-tests. The Monte Carlo DICOM ToolKit software was adapted to permit the evaluation of dose metrics from DICOM data exported from a commercial radiotherapy treatment planning system. The 3DCRT treatment plans offered greater planning target volume dose homogeneity than the other two treatment modalities. The IMRT and VMAT plans offered greater dose reduction in the OAR: with increased compliance with recommended OAR dose constraints, compared to conventional 3DCRT treatments. When compared to each other, IMRT and VMAT did not provide significantly different treatment plan quality for like-sized tumour volumes. This study indicates that IMRT and VMAT have provided similar dosimetric quality, which is superior to the dosimetric quality achieved with 3DCRT.

Postoperative intensity-modulated irradiation (IMRT) of endometrial cancers: results of the 'dummy run' quality assurance procedure for phase 2 RTCMIENDOMETRE multicentric French test; Irradiation avec modulation d'intensite (RCMI) postoperatoire des cancers de l'endometre: resultats de la procedure d'assurance de qualite -dummy run- de l'essai francais multicentrique de phase 2 RTCMIENDOMETRE

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Kreps, S.; Barillot, I. [CHU de Tours, 37 - Tours (France); Peignaux, K. [Centre Georges FrancoisLeclerc, 21 - Dijon (France); Nickers, P. [Centre Oscar Lambret, 59 - Lille (France); Leblanc-Onfroy, M. [Centre Rene-Gauducheau, 44 - Nantes (France); Williaume, D. [Centre Eugene-Marquis, 35 - Rennes (France); Haie-Meder, C. [Institut Gustave-Roussy, 94 - Villejuif (France); Lerouge, D. [Centre Francois Baclesse, 14 - Caen (France)

2010-10-15

The authors report a study which aims at assessing the impact of the intensity-modulated conformational radiotherapy on the acute intestinal toxicity of a postoperative irradiation of stage I and II endometrial cancers. Seven radiotherapy centres participated to this study. They followed a 'dummy run' procedure in order to assess their ability to respect the irradiation protocol. The authors discuss the contouring correlation for different organs. The use of the Radiation Therapy Oncology Group (RTOG) atlas leads to a better concordance between the centres. Short communication

Efficacy of intensity-modulated radiotherapy combined with chemotherapy or surgery in locally advanced squamous cell carcinoma of the head-and-neck

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Yang H

2013-10-01

Full Text Available Hua Yang,* Li-Qiong Diao,* Mei Shi, Rui Ma, Jian-Hua Wang, Jian-Ping Li, Feng Xiao, Ying Xue, Man Xu, Bin ZhouDepartment of Radiotherapy Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, People's Republic of China*These authors contributed equally to this workObjectives: Long-term locoregional control following intensity-modulated radiotherapy (IMRT for locally advanced squamous cell carcinoma of the head-and-neck (SCCHN remains challenging. This study aimed to assess the efficacy and toxicity of IMRT with and without chemotherapy or surgery in locally advanced SCCHN.Materials and methods: Between January 2007 and January 2011, 61 patients with locally advanced SCCHN were treated with curative IMRT in the Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University; 28% underwent definitive IMRT and 72% postoperative IMRT, combined with simultaneous cisplatin-based chemotherapy in 58%. The mean doses of definitive and postoperative IMRT were 70.8 Gy (range, 66–74 Gy. Outcomes were analyzed using Kaplan–Meier curves. Acute and late toxicities were graded according to Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer radiation morbidity scoring criteria.Results: At a median follow-up of 35 months, 3-year local recurrence-free survival (LRFS, regional recurrence-free survival (RRFS, distant metastasis-free survival (DMFS, disease-free survival (DFS, and overall survival (OS were 83.8%, 86.1%, 82.4%, 53.2%, and 62%, respectively. Postoperative IMRT (n = 44, 72% had significantly higher LRFS/OS/DMFS than definitive IMRT (n = 17, 28%; P < 0.05. IMRT combined with chemotherapy (n = 35, 58% had significantly higher LRFS/OS/DMFS than IMRT alone (n = 26, 42%; P < 0.05. One year after radiotherapy, the incidence of xerostomia of grade 1, 2, or 3 was 13.1%, 19.7%, and 1.6%, respectively. No grade 4 acute or late toxicity was observed.Conclusion: IMRT combined with

Pelvic Ewing sarcomas. Three-dimensional conformal vs. intensity-modulated radiotherapy

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Mounessi, F.S.; Lehrich, P.; Haverkamp, U.; Eich, H.T. [Muenster Univ. (Germany). Dept. of Radiation Oncology; Willich, N. [Muenster Univ. (Germany). Dept. of Radiation Oncology; Universitaetsklinikum Muenster (Germany). RiSK - Registry for the Evaluation of Late Side Effects after Radiotherapy in Childhood and Adolescence; Boelling, T. [Center for Radiation Oncology, Osnabrueck (Germany)

2013-04-15

The goal of the present work was to assess the potential advantage of intensity-modulated radiotherapy (IMRT) over three-dimensional conformal radiotherapy (3D-CRT) planning in pelvic Ewing's sarcoma. A total of 8 patients with Ewing sarcoma of the pelvis undergoing radiotherapy were analyzed. Plans for 3D-CRT and IMRT were calculated for each patient. Dose coverage of the planning target volume (PTV), conformity and homogeneity indices, as well as further parameters were evaluated. Results The average dose coverage values for PTV were comparable in 3D-CRT and IMRT plans. Both techniques had a PTV coverage of V{sub 95} > 98 % in all patients. Whereas the IMRT plans achieved a higher conformity index compared to the 3D-CRT plans (conformity index 0.79 {+-} 0.12 vs. 0.54 {+-} 0.19, p = 0.012), the dose distribution across the target volumes was less homogeneous with IMRT planning than with 3D-CRT planning. This difference was statistically significant (homogeneity index 0.11 {+-} 0.03 vs. 0.07 {+-} 0.0, p = 0.035). For the bowel, D{sub mean} and D{sub 1%}, as well as V{sub 2} to V{sub 60} were reduced in IMRT plans. For the bladder and the rectum, there was no significant difference in D{sub mean}. However, the percentages of volumes receiving at least doses of 30, 40, 45, and 50 Gy (V{sub 30} to V{sub 50}) were lower for the rectum in IMRT plans. The volume of normal tissue receiving at least 2 Gy (V{sub 2}) was significantly higher in IMRT plans compared with 3D-CRT, whereas at high dose levels (V{sub 30}) it was significantly lower. Compared to 3D-CRT, IMRT showed significantly better results regarding dose conformity (p = 0.012) and bowel sparing at dose levels above 30 Gy (p = 0.012). Thus, dose escalation in the radiotherapy of pelvic Ewing's sarcoma can be more easily achieved using IMRT. (orig.)

Cardiac Exposure in the Dynamic Conformal Arc Therapy, Intensity-Modulated Radiotherapy and Volumetric Modulated Arc Therapy of Lung Cancer.

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Xin Ming

Full Text Available To retrospectively evaluate the cardiac exposure in three cohorts of lung cancer patients treated with dynamic conformal arc therapy (DCAT, intensity-modulated radiotherapy (IMRT, or volumetric modulated arc therapy (VMAT at our institution in the past seven years.A total of 140 lung cancer patients were included in this institutional review board approved study: 25 treated with DCAT, 70 with IMRT and 45 with VMAT. All plans were generated in a same commercial treatment planning system and have been clinically accepted and delivered. The dose distribution to the heart and the effects of tumor laterality, the irradiated heart volume and the beam-to-heart distance on the cardiac exposure were investigated.The mean dose to the heart among all 140 plans was 4.5 Gy. Specifically, the heart received on average 2.3, 5.2 and 4.6 Gy in the DCAT, IMRT and VMAT plans, respectively. The mean heart doses for the left and right lung tumors were 4.1 and 4.8 Gy, respectively. No patients died with evidence of cardiac disease. Three patients (2% with preexisting cardiac condition developed cardiac disease after treatment. Furthermore, the cardiac exposure was found to increase linearly with the irradiated heart volume while decreasing exponentially with the beam-to-heart distance.Compared to old technologies for lung cancer treatment, modern radiotherapy treatment modalities demonstrated better heart sparing. But the heart dose in lung cancer radiotherapy is still higher than that in the radiotherapy of breast cancer and Hodgkin's disease where cardiac complications have been extensively studied. With strong correlations of mean heart dose with beam-to-heart distance and irradiated heart volume, cautions should be exercised to avoid long-term cardiac toxicity in the lung cancer patients undergoing radiotherapy.

BENEFITS OF INTENSITY-MODULATED RADIOTHERAPY (IMRT IN PATIENTS WITH HEAD AND NECK MALIGNANCIES- A SINGLE INSTITUTION EXPERIENCE

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Sherry Seasor Abraham

2017-09-01

Full Text Available BACKGROUND Radiotherapy and surgery are the principal curative modalities in treatment of head and neck cancer. Conventional twodimensional and three-dimensional conformal radiotherapy result in significant side effects and altered quality of life. IntensityModulated Radiotherapy (IMRT can spare the normal tissues, while delivering a curative dose to the tumour-bearing tissues. This study reveals the role of IMRT in head and neck cancer in view of normal tissue sparing with good tumour control. MATERIALS AND METHODS Radical radiotherapy was given using linear accelerator up to a dose of 66 to 70 gray in 30 to 33 fractions (intensity-modulated radiotherapy with simultaneous integrated boost over 6 to 7 weeks to 56 eligible patients. Concurrent cisplatin was given to patients with locally-advanced disease up to a dose of 40 mg/m2 weekly once along with radiation. The patients were monitored weekly once during the treatment for acute skin and mucosal toxicities using the RTOG scoring criteria. After the treatment, locoregional response was assessed and recorded at 6 weeks, 3 months and 6 months intervals. RESULTS Severe skin toxicity (grade III or more was seen in approximately 7% patients. Severe mucosal toxicity (grade III or more was seen in approximately 80% of patients. IMRT technique showed better skin sparing compared to 3D conformal radiotherapy. Severe mucosal toxicity was slightly higher in this study due to the simultaneous integrated boost technique used for dose intensification to the mucosa, which results in better primary tumour control. At the end of 6 months, 75% patients achieved locoregional control and residual/recurrent disease was seen in 25% of patients. IMRT offered good locoregional control with less skin toxicity and acceptable mucosal toxicity. The results were similar to the previous study reports using IMRT. CONCLUSION IMRT is a better treatment option in locally-advanced head and neck malignancies providing good

Dosimetric aspects of breast radiotherapy with three-dimensional and intensity-modulated radiotherapy helical tomotherapy planning modules

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Yadav, Poonam [Department of Human Oncology, University of Wisconsin-Madison, Madison, WI (United States); Service of Radiation Therapy, University of Wisconsin Aspirus Cancer Center, Wisconsin Rapids, WI (United States); Yan, Yue, E-mail: yyan5@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Ignatowski, Tasha [Service of Radiation Therapy, University of Wisconsin Aspirus Cancer Center, Wisconsin Rapids, WI (United States); Olson, Anna [Department of Human Oncology, University of Wisconsin-Madison, Madison, WI (United States); Service of Radiation Therapy, University of Wisconsin Aspirus Cancer Center, Wisconsin Rapids, WI (United States)

2017-04-01

In this work, we investigated the dosimetric differences between the intensity-modulated radiotherapy (IMRT) plans and the three-dimensional (3D) helical plans based on the TomoTherapy system. A total of 15 patients with supine setup were randomly selected from the data base. For patients with lumpectomy planning target volume (PTV), regional lymph nodes were also included as part of the target. For dose sparing, the significant differences between the helical IMRT and helical 3D were only found in the heart and contralateral breast. For the dose to the heart, helical IMRT reduced the maximum point dose by 6.98 Gy compared to the helical 3D plan (p = 0.01). For contralateral breast, the helical IMRT plans significantly reduced the maximum point dose by 5.6 Gy compared to the helical 3D plan. However, compared to the helical 3D plan, the helical IMRT plan increased the volume for lower dose (13.08% increase in V{sub 5} {sub Gy}, p = 0.01). In general, there are no significant differences in dose sparing between helical IMRT and helical 3D plans.

Study on the possibility of using a 60 Co therapeutical unity in Intensity Modulated Radiotherapy (IMRT)

International Nuclear Information System (INIS)

Dantas, Samuel Cesar

2009-06-01

With the increasing advances in complex treatment techniques, there is a tendency to obtain more sophisticated equipment to deliver the dose. The use of 3D conformal radiotherapy is now routine in many radiotherapy facilities as well as the utilization of intensity modulated radiotherapy (IMRT). Both are usually implemented using linear accelerators equipped with multi leaves collimators, which create the conformity and the fluence distributions required. However, the complexity of increasingly sophisticated equipment, such as linear accelerators, requires a frequent quality control of their operation, as well as a detailed and constant maintenance. Even carrying out these procedures, the accelerators may present technical problems interrupting for a long time a treatment using the IMRT technique. Despite the clear practical and technological advantages that linear accelerators have on 60 Co irradiators, these devices occupy an important place in radiotherapy, mainly due to the low cost of equipment installation and maintenance when compared to those required by accelerators. Many radiotherapy facilities that work with IMRT have tele therapeutic isocentric 60 Co units. In principle, such equipment would be able to be used for treatment with IMRT using compensating blocks to modulate the beam. This study investigates this possibility and shows that it is feasible. The comparison of treatment plans of a head-and-neck cancer and other of a cancer of the central nervous system, based on a 60 Co irradiator and a Linac 2300 C/D, presented advantages for the 60 Co irradiator. Furthermore; the delivery of dose obtained with the two systems showed themselves equivalent when compared to their respective plans. (author)

Breast-conserving radiation therapy using combined electron and intensity-modulated radiotherapy technique

International Nuclear Information System (INIS)

Li, J.G.; Williams, S.S.; Goffinet, D.R.; Boer, A.L.; Xing, L.

2000-01-01

An electron beam with appropriate energy was combined with four intensity modulated photon beams. The direction of the electron beam was chosen to be tilted 10-20 laterally from the anteroposterior direction. Two of the intensity-modulated photon beams had the same gantry angles as the conventional tangential fields, whereas the other two beams were rotated 15-25' toward the anteroposterior directions from the first two photon beams. An iterative algorithm was developed which optimizes the weight of the electron beam as well as the fluence profiles of the photon beams for a given patient. Two breast cancer patients with early-stage breast tumors were planned with the new technique and the results were compared with those from 3D planning using tangential fields as well as 9-field intensity-modulated radiotherapy (IMRT) techniques. The combined electron and IMRT plans showed better dose conformity to the target with significantly reduced dose to the ipsilateral lung and, in the case of the left-breast patient, reduced dose to the heart, than the tangential field plans. In both the right-sided and left-sided breast plans, the dose to other normal structures was similar to that from conventional plans and was much smaller than that from the 9-field IMRT plans. The optimized electron beam provided between 70 to 80% of the prescribed dose at the depth of maximum dose of the electron beam. The combined electron and IMRT technique showed improvement over the conventional treatment technique using tangential fields with reduced dose to the ipsilateral lung and the heart. The customized beam directions of the four IMRT fields also kept the dose to other critical structures to a minimum. (author)

Treatment outcome in patients with vulvar cancer: comparison of concurrent radiotherapy to postoperative radiotherapy

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Lee, Ja Young; Kim, Sung Hwan; Kim, Ki Won; Park, Dong Choon; Yoon, Joo Hee; Yoon, Sei Chul [St. Vincent' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of); Yu, Mina [St. Mary' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of)

2012-03-15

To evaluate outcome and morbidity in patients with vulvar cancer treated with radiotherapy, concurrent chemoradiotherapy or postoperative radiotherapy. The records of 24 patients treated with radiotherapy for vulvar cancer between July 1993 and September 2009 were retrospectively reviewed. All patients received once daily 1.8-4 Gy fractions external beam radiotherapy to median 51.2 Gy (range, 19.8 to 81.6 Gy) on pelvis and inguinal nodes. Seven patients were treated with primary concurrent chemoradiotherapy, one patient was treated with primary radiotherapy alone, four patients received palliative radiotherapy, and twelve patients were treated with postoperative radiotherapy. Twenty patients were eligible for response evaluation. Response rate was 55% (11/20). The 5-year disease free survival was 42.2% and 5-year overall survival was 46.2%, respectively. Fifty percent (12/24) experienced with acute skin complications of grade III or more during radiotherapy. Late complications were found in 8 patients. 50% (6/12) of patients treated with lymph node dissection experienced severe late complications. One patient died of sepsis from lymphedema. However, only 16.6% (2/12) of patients treated with primary radiotherapy developed late complications. Outcome of patients with vulvar cancer treated with radiotherapy showed relatively good local control and low recurrence. Severe late toxicities remained higher in patients treated with both node dissection and radiotherapy.

Preoperative Intensity-Modulated Radiotherapy Combined with Temozolomide for Locally Advanced Soft-Tissue Sarcoma

International Nuclear Information System (INIS)

Jakob, Jens; Wenz, Frederik; Dinter, Dietmar J.; Stroebel, Philipp; Hohenberger, Peter

2009-01-01

Purpose: To evaluate the toxicity and efficacy of preoperative intensity-modulated radiotherapy (IMRT) combined with temozolomide to improve local tumor control in soft-tissue sarcoma (STS). Patients and Methods: A cohort of 15 consecutive patients with nonmetastasized, primary high-grade or locally recurrent Stage III (n = 14) or IIb (n = 1) STS not amenable to surgical resection without significant organ or extremity function loss was prospectively investigated. Median tumor size was 9.8 cm, and most tumors were non-extremity sarcomas. Patients preoperatively received 50 mg/m 2 of temozolomide during IMRT (50.4 Gy). Resection was intended 6 weeks thereafter. Toxicity was assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0, and response was assessed by Response Evaluation Criteria in Solid Tumors. Results: Of 15 patients, 14 completed preoperative treatment. No Grade 4 toxicities occurred. Nausea and vomiting were the most frequent Grade 3 toxicities. The most frequent toxicities of any grade were dermatologic, gastrointestinal, and hematologic. Response was partial response in 5, stable disease in 7, and progressive disease in 2 patients. Ten patients underwent surgery: 7 were resected with clear margins (R0), and 2 patients had an R1 resection; in 1 patient the tumor was not resectable. Postoperative complications occurred in 4 patients. Five patients did not undergo surgery because of intercurrent metastatic disease, unresectable disease, or refusal. Conclusions: Preoperative chemoradiation with temozolomide and IMRT can be administered safely and with promising efficacy in patients with locally advanced STS.

Radiotherapy for Adult Medulloblastoma: Evaluation of Helical Tomotherapy, Volumetric Intensity Modulated Arc Therapy, and Three-Dimensional Conformal Radiotherapy and the Results of Helical Tomotherapy Therapy

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Sun Zong-wen

2018-01-01

Full Text Available Introduction. All adult medulloblastoma (AMB patients should be treated with craniospinal irradiation (CSI postoperatively. Because of the long irradiation range, multiple radiation fields must be designed for conventional radiotherapy technology. CSI can be completed in only one session with helical tomotherapy (HT. We evaluated the dose of HT, volumetric intensity modulated arc therapy (VMAT, and three-dimensional conformal radiotherapy (3D-CRT of AMB and the results of 5 cases of AMB treated with HT. Methods. Complete craniospinal and posterior cranial fossa irradiation with HT, VMAT, and 3D-CRT and dose evaluation were performed. And results of 5 cases of AMB treated with HT were evaluated. Results. A large volume of tissue was exposed to low dose radiation in the organs at risk (OAR, while a small volume was exposed to high dose radiation with HT. The conformity and uniformity of the targets were good with HT and VMAT, and the volume of targets exposed to high dose with VMAT was larger than that of HT. The uniformity of 3D-CRT was also good, but the dose conformity was poor. The main toxicity was hematologic toxicity, without 4th-degree bone marrow suppression. There was 3rd-degree inhibition in the white blood cells, hemoglobin, and platelets. The three female patients suffered menstrual disorders during the course of radiation. Two female patients with heavy menstruation suffered 3rd-degree anemia inhibition, and 2 patients suffered amenorrhea after radiotherapy. Although menstrual cycle was normal, the third patient was not pregnant. Conclusion. CSI with HT is convenient for clinical practice, and the side effects are mild. With good conformity and uniformity, VMAT can also be used for selection in CSI. For poor conformity, 3D-CRT should not be the priority selection for CSI. In female patients, the ovaries should be protected.

Rectal toxicity after intensity modulated radiotherapy for prostate cancer: Which rectal dose volume constraints should we use?

International Nuclear Information System (INIS)

Fonteyne, Valérie; Ost, Piet; Vanpachtenbeke, Frank; Colman, Roos; Sadeghi, Simin; Villeirs, Geert; Decaestecker, Karel; De Meerleer, Gert

2014-01-01

Background: To define rectal dose volume constraints (DVC) to prevent ⩾grade2 late rectal toxicity (LRT) after intensity modulated radiotherapy (IMRT) for prostate cancer (PC). Material and methods: Six hundred thirty-seven PC patients were treated with primary (prostate median dose: 78 Gy) or postoperative (prostatic bed median dose: 74 Gy (adjuvant)–76 Gy (salvage)) IMRT while restricting the rectal dose to 76 Gy, 72 Gy and 74 Gy respectively. The impact of patient characteristics and rectal volume parameters on ⩾grade2 LRT was determined. DVC were defined to estimate the 5% and 10% risk of developing ⩾grade2 LRT. Results: The 5-year probability of being free from ⩾grade2 LRT, non-rectal blood loss and persisting symptoms is 88.8% (95% CI: 85.8–91.1%), 93.4% (95% CI: 91.0–95.1%) and 94.3% (95% CI: 92.0–95.9%) respectively. There was no correlation with patient characteristics. All volume parameters, except rectal volume receiving ⩾70 Gy (R70), were significantly correlated with ⩾grade2 LRT. To avoid 10% and 5% risk of ⩾grade2 LRT following DVC were derived: R40, R50, R60 and R65 <64–35%, 52–22%, 38–14% and 5% respectively. Conclusion: Applying existing rectal volume constraints resulted in a 5-year estimated risk of developing late ⩾grade2 LRT of 11.2%. New rectal DVC for primary and postoperative IMRT planning of PC patients are proposed. A prospective evaluation is needed

Intensity-Modulated Radiotherapy in the Treatment of Oropharyngeal Cancer: Clinical Outcomes and Patterns of Failure

International Nuclear Information System (INIS)

Daly, Megan E.; Le, Quynh-Thu; Maxim, Peter G.; Loo, Billy W.; Kaplan, Michael J.; Fischbein, Nancy J.; Pinto, Harlan; Chang, Daniel T.

2010-01-01

Purpose: To report outcomes, failures, and toxicities in patients treated with intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma of the oropharynx. Methods And Materials: Between Aug 2001 and Oct 2007, 107 patients were treated with IMRT with curative intent at Stanford University. Twenty-two patients were treated postoperatively, and 85 were treated definitively. Concurrent platinum-based chemotherapy was administered to 86 patients (80%) and cetuximab to 8 patients (7%). The prescribed dose was 66 Gy at 2.2 Gy/fraction for definitively treated cases and 60 Gy at 2 Gy/fraction for postoperative cases. Median follow-up was 29 months among surviving patients (range, 4-105 months). Results: Eight patients had persistent disease or local-regional failure at a median of 6.5 months (range, 0-9.9 months). Six local failures occurred entirely within the high-risk clinical target volume (CTV) (one with simultaneous distant metastasis). One patient relapsed within the high- and intermediate-risk CTV. One patient had a recurrence at the junction between the IMRT and low-neck fields. Seven patients developed distant metastasis as the first site of failure. The 3-year local-regional control (LRC), freedom from distant metastasis, overall survival, and disease-free survival rates were 92%, 92%, 83%, and 81%, respectively. T stage (T4 vs. T1-T3) was predictive of poorer LRC (p = 0.001), overall survival (p = 0.001), and disease-free survival (p < 0.001) rates. Acute toxicity consisted of 58% grade 3 mucosal and 5% grade 3 skin reactions. Six patients (6%) developed grade ≥3 late complications. Conclusions: IMRT provides excellent LRC for oropharyngeal squamous cell carcinoma. Distant metastases are a major failure pattern. No marginal failures were observed.

Dosimetric comparison of intensity modulated radiotherapy techniques and standard wedged tangents for whole breast radiotherapy

International Nuclear Information System (INIS)

Fong, Andrew; Bromley, Regina; Beat, Mardi; Vien, Din; Dineley, Jude; Morgan, Graeme

2009-01-01

Full text: Prior to introducing intensity modulated radiotherapy (IMRT) for whole breast radiotherapy (WBRT) into our department we undertook a comparison of the dose parameters of several IMRT techniques and standard wedged tangents (SWT). Our aim was to improve the dose distribution to the breast and to decrease the dose to organs at risk (OAR): heart, lung and contralateral breast (Contra Br). Treatment plans for 20 women (10 right-sided and 10 left-sided) previously treated with SWT for WBRT were used to compare (a) SWT; (b) electronic compensators IMRT (E-IMRT); (c) tangential beam IMRT (T-IMRT); (d) coplanar multi-field IMRT (CP-IMRT); and (e) non-coplanar multi-field IMRT (NCP-IMRT). Plans for the breast were compared for (i) dose homogeneity (DH); (ii) conformity index (CI); (iii) mean dose; (iv) maximum dose; (v) minimum dose; and dose to OAR were calculated (vi) heart; (vii) lung and (viii) Contra Br. Compared with SWT, all plans except CP-IMRT gave improvement in at least two of the seven parameters evaluated. T-IMRT and NCP-IMRT resulted in significant improvement in all parameters except DH and both gave significant reduction in doses to OAR. As on initial evaluation NCP-IMRT is likely to be too time consuming to introduce on a large scale, T-IMRT is the preferred technique for WBRT for use in our department.

Intensity modulated radiotherapy and 3D conformal radiotherapy for whole breast irradiation: a comparative dosimetric study and introduction of a novel qualitative index for plan evaluation, the normal tissue index

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Yim, Jackie; Suttie, Clare; Bromley, Regina; Morgia, Marita; Lamoury, Gillian [Department of Radiation Oncology, Royal North Shore Hospital, St Leonards, New South Wales (Australia)

2015-09-15

We report on a retrospective dosimetric study, comparing 3D conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (hIMRT). We evaluated plans based on their planning target volume coverage, dose homogeneity, dose to organs at risk (OARs) and exposure of normal tissue to radiation. The Homogeneity Index (HI) was used to assess the dose homogeneity in the target region, and we describe a new index, the normal tissue index (NTI), to assess the dose in the normal tissue inside the tangent treatment portal. Plans were generated for 25 early-stage breast cancer patients, using a hIMRT technique. These were compared with the 3DCRT plans of the treatment previously received by the patients. Plan quality was evaluated using the HI, NTI and dose to OARs. The hIMRT technique was significantly more homogenous than the 3DCRT technique, while maintaining target coverage. The hIMRT technique was also superior at minimising the amount of tissue receiving D{sub 105%} and above (P < 0.0001). The ipsilateral lung and contralateral breast maximum were significantly lower in the hIMRT plans (P < 0.05 and P < 0.005), but the 3DCRT technique achieved a lower mean heart dose in left-sided breast cancer patients (P < 0.05). Hybrid intensity modulated radiotherapy plans achieved improved dose homogeneity compared to the 3DCRT plans and superior outcome with regard to dose to normal tissues. We propose that the addition of both HI and NTI in evaluating the quality of intensity modulated radiotherapy (IMRT) breast plans provides clinically relevant comparators which more accurately reflect the new paradigm of treatment goals and outcomes in the era of breast IMRT.

Intensity modulated radiotherapy and 3D conformal radiotherapy for whole breast irradiation: a comparative dosimetric study and introduction of a novel qualitative index for plan evaluation, the normal tissue index

International Nuclear Information System (INIS)

Yim, Jackie; Suttie, Clare; Bromley, Regina; Morgia, Marita; Lamoury, Gillian

2015-01-01

We report on a retrospective dosimetric study, comparing 3D conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (hIMRT). We evaluated plans based on their planning target volume coverage, dose homogeneity, dose to organs at risk (OARs) and exposure of normal tissue to radiation. The Homogeneity Index (HI) was used to assess the dose homogeneity in the target region, and we describe a new index, the normal tissue index (NTI), to assess the dose in the normal tissue inside the tangent treatment portal. Plans were generated for 25 early-stage breast cancer patients, using a hIMRT technique. These were compared with the 3DCRT plans of the treatment previously received by the patients. Plan quality was evaluated using the HI, NTI and dose to OARs. The hIMRT technique was significantly more homogenous than the 3DCRT technique, while maintaining target coverage. The hIMRT technique was also superior at minimising the amount of tissue receiving D 105% and above (P < 0.0001). The ipsilateral lung and contralateral breast maximum were significantly lower in the hIMRT plans (P < 0.05 and P < 0.005), but the 3DCRT technique achieved a lower mean heart dose in left-sided breast cancer patients (P < 0.05). Hybrid intensity modulated radiotherapy plans achieved improved dose homogeneity compared to the 3DCRT plans and superior outcome with regard to dose to normal tissues. We propose that the addition of both HI and NTI in evaluating the quality of intensity modulated radiotherapy (IMRT) breast plans provides clinically relevant comparators which more accurately reflect the new paradigm of treatment goals and outcomes in the era of breast IMRT

Dosimetric Evaluation of Intensity Modulated Radiotherapy and 4-Field 3-D Conformal Radiotherapy in Prostate Cancer Treatment

Directory of Open Access Journals (Sweden)

Bora Uysal

2013-03-01

Full Text Available Objective: The purpose of this dosimetric study is the targeted dose homogeneity and critical organ dose comparison of 7-field Intensity Modulated Radiotherapy (IMRT and 3-D 4-field conformal radiotherapy. Study Design: Cross sectional study. Material and Methods: Twenty patients with low and moderate risk prostate cancer treated at Gülhane Military Medical School Radiation Oncology Department between January 2009 and December 2009 are included in this study. Two seperate dosimetric plans both for 7-field IMRT and 3D-CRT have been generated for each patient to comparatively evaluate the dosimetric status of both techniques and all the patients received 7-field IMRT. Results: Dose-comparative evaluation of two techniques revealed the superiority of IMRT technique with statistically significantly lower femoral head doses along with reduced critical organ dose-volume parameters of bladder V60 (the volume receiving 60 Gy and rectal V40 (the volume receiving 40 Gy and V60. Conclusion: It can be concluded that IMRT is an effective definitive management tool for prostate cancer with improved critical organ sparing and excellent dose homogenization in target organs of prostate and seminal vesicles.

Some aspects of the design of intensity modulated beams for breast radiotherapy

International Nuclear Information System (INIS)

Evans, PM; Hansen, VN; Swindell, W

1995-01-01

An electronic portal imaging system has been used to design intensity modulated beams to achieve compensation for missing tissue and tissue heterogeneity in tangential irradiation of the breast. A portal image of the breast is calibrated for radiological thickness and an estimate of the outline of lung and soft tissue is made. This is used with the desired dose prescription to design intensity modulated beams, IMBs. The practical implementation of the IMBs may be achieved using a multileaf collimator, MLC. The leaves of the MLC may be scanned dynamically or a set of multiple static fields may be used. We have compared the uniformity of the achievable dose distribution for both cases. In the static case, the effects of varying the number of fields and their relative intensities have been investigated. The use of scanning leaves yields a dose distribution which is close to optimal. Multiple static fields produce results close to optimal if a large number, typically 30 are used. However, even for the more practicable case of 5 fields, the hot and cold spots are significantly reduced compared to a simple wedge. When studying the optimum intensity distribution for the set of static fields, it was found that having the first field with a large intensity irradiating the whole target volume and a set of 'top-up' fields of equal magnitude was best. This study suggests that an MLC may indeed be used to deliver IMBs for radiotherapy of the breast. We can presently deliver the multiple static field technique. For the small number of beams which are presently deliverable, an improvement of dosimetry over the use of a simple wedge is indicated. In the future, with the scanning leaves technique, dose distributions with greatly reduced dose inhomogeneities should be achievable

Dynamic intensity-modulated non-coplanar arc radiotherapy (INCA) for head and neck cancer

International Nuclear Information System (INIS)

Krayenbuehl, Jerome; Davis, J. Bernard; Ciernik, I. Frank

2006-01-01

Background and purpose: To define the potential advantages of intensity-modulated radiotherapy (IMRT) applied using a non-coplanar dynamic arc technique for the treatment of head and neck cancer. Materials and methods: External beam radiotherapy (EBRT) was planned in ten patients with head and neck cancer using coplanar IMRT and non-coplanar arc techniques, termed intensity modulated non-coplanar arc EBRT (INCA). Planning target volumes (PTV1) of first order covered the gross tumor volume and surrounding clinical target volume treated with 68-70 Gy, whereas PTV2 covered the elective lymph nodes with 54-55 Gy using a simultaneous internal boost. Treatment plan comparison between IMRT and INCA was carried out using dose-volume histogram and 'equivalent uniform dose' (EUD). Results: INCA resulted in better dose coverage and homogeneity of the PTV1, PTV2, and reduced dose delivered to most of the organs at risk (OAR). For the parotid glands, a reduction of the mean dose of 2.9 (±2.0) Gy was observed (p 0.002), the mean dose to the larynx was reduced by 6.9 (±2.9) Gy (p 0.003), the oral mucosa by 2.4 (±1.1) Gy (p < 0.001), and the maximal dose to the spinal cord by 3.2 (±1.7) Gy (p = 0.004). The mean dose to the brain was increased by 3.0 (±1.4) Gy (p = 0.002) and the mean lung dose increased by 0.2 (±0.4) Gy (p = 0.87). The EUD suggested better avoidance of the OAR, except for the lung, and better coverage and dose uniformity were achieved with INCA compared to IMRT. Conclusion: Dose delivery accuracy with IMRT using a non-coplanar dynamic arc beam geometry potentially improves treatment of head and neck cancer

SU-E-T-808: Volumetric Modulated Arc Radiotherapy Vs. Intensity-Modulated Radiotherapy for Early-Stage Nasopharyngeal Carcinoma: A Dosimetric Study

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Lu, J-Y; Huang, B-T; Zhang, W-Z [Cancer Hospital of Shantou University Medical College, Shantou, Guangdong (China)

2015-06-15

Purpose: To compare volumetric modulated arc radiotherapy (VMAT) technique with fixed-gantry intensity-modulated radiotherapy (IMRT) technique for early-stage nasopharyngeal carcinoma. Methods: CT datasets of ten patients with early-stage nasopharyngeal carcinoma were included. Dual-arc VMAT and nine-field IMRT plans were generated for each case, and were then compared in terms of planning-target-volume (PTV) coverage, conformity index (CI) and homogeneity index (HI), as well as organ-at-risk (OAR) sparing, planning time, monitor units (MUs) and delivery time. Results: Compared with the IMRT plans, the VMAT plans provided comparable HI and CI of PTVnx (PTV of primary tumor of nasopharynx), superior CI and inferior HI of PTVnd (PTV of lymph nodes), as well as superior CI and comparable HI of PTV60 (high-risk PTV). The VMAT plans provided better sparing of the spinal cord, oral cavity and normal tissue, but inferior sparing of the brainstem planning OAR volume (PRV), larynx and parotids, as well as comparable sparing of the spinal cord PRV, brainstem, lenses, optic nerves, optic chiasm. Moreover, the average planning time (181.6 ± 36.0 min) for the VMAT plans was 171% more than that of the IMRT plans (68.1 ± 7.6 min). The MUs of the VMAT plans (609 ± 43) were 70% lower than those of the IMRT plans (2071 ± 262), while the average delivery time (2.2 ± 0.1 min) was 66% less than that of the IMRT plans (6.6 ± 0.4 min). Conclusion: Compared with the IMRT technique, the VMAT technique can achieve similar or slightly superior target dose distribution, with no significant advantages on OAR sparing, and it can achieve significant reductions of MUs and delivery time.

SU-E-T-808: Volumetric Modulated Arc Radiotherapy Vs. Intensity-Modulated Radiotherapy for Early-Stage Nasopharyngeal Carcinoma: A Dosimetric Study

International Nuclear Information System (INIS)

Lu, J-Y; Huang, B-T; Zhang, W-Z

2015-01-01

Purpose: To compare volumetric modulated arc radiotherapy (VMAT) technique with fixed-gantry intensity-modulated radiotherapy (IMRT) technique for early-stage nasopharyngeal carcinoma. Methods: CT datasets of ten patients with early-stage nasopharyngeal carcinoma were included. Dual-arc VMAT and nine-field IMRT plans were generated for each case, and were then compared in terms of planning-target-volume (PTV) coverage, conformity index (CI) and homogeneity index (HI), as well as organ-at-risk (OAR) sparing, planning time, monitor units (MUs) and delivery time. Results: Compared with the IMRT plans, the VMAT plans provided comparable HI and CI of PTVnx (PTV of primary tumor of nasopharynx), superior CI and inferior HI of PTVnd (PTV of lymph nodes), as well as superior CI and comparable HI of PTV60 (high-risk PTV). The VMAT plans provided better sparing of the spinal cord, oral cavity and normal tissue, but inferior sparing of the brainstem planning OAR volume (PRV), larynx and parotids, as well as comparable sparing of the spinal cord PRV, brainstem, lenses, optic nerves, optic chiasm. Moreover, the average planning time (181.6 ± 36.0 min) for the VMAT plans was 171% more than that of the IMRT plans (68.1 ± 7.6 min). The MUs of the VMAT plans (609 ± 43) were 70% lower than those of the IMRT plans (2071 ± 262), while the average delivery time (2.2 ± 0.1 min) was 66% less than that of the IMRT plans (6.6 ± 0.4 min). Conclusion: Compared with the IMRT technique, the VMAT technique can achieve similar or slightly superior target dose distribution, with no significant advantages on OAR sparing, and it can achieve significant reductions of MUs and delivery time

SU-E-T-302: Dosimetric Comparison Between Volumetric Modulated Arc Radiotherapy and Intensity-Modulated Radiotherapy for Locally Recurrent Nasopharyngeal Carcinoma

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Lu, J-Y; Huang, B-T; Zhang, J-Y; Ma, C-C [Cancer Hospital of Shantou University Medical College, Shantou, Guangdong (China)

2015-06-15

Purpose: To compare volumetric modulated arc radiotherapy (VMAT) technique with fixed-gantry intensity-modulated radiotherapy (IMRT) technique for locally recurrent nasopharyngeal carcinoma. Methods: CT datasets of eleven nasopharyngeal-carcinoma patients were included. Dual-arc VMAT and seven-field IMRT plans were created for each case, and were then compared in terms of conformity index (CI), homogeneity index (HI) of the planning target volume (PTV), organ-at-risk (OAR) sparing, monitor unit (MU) and delivery time. Results: The D98% (near-minimal dose) of PTV in the VMAT plans was slightly lower than that of the IMRT plans (P < 0.05), while the CI was higher than that of the IMRT plans (P < 0.05). No significant difference was found in the HI between the two plans (P > 0.05). Compared with the IMRT plans, the VMAT plans demonstrated lower Dmean (mean dose) of the bilateral temporal lobes and the whole surrounding normal tissue (P < 0.05), but slightly higher Dmean of brainstem (P < 0.05). In terms of the other OARs, no significant differences were found (P > 0.05). The MUs of the VMAT plans (672 ± 112) was significantly lower than that of the IMRT plans (917 ± 206), by 25 ± 13% (P < 0.05). The average delivery time of the VMAT plans (2.3 ± 0.1 min) was less than that of the IMRT plans (5.1 ± 0.4 min), by 54 ± 3%. Conclusion: For locally recurrent nasopharyngeal carcinoma, the VMAT technique could achieve equivalent or superior dose distribution of the target and better protect the bilateral temporal lobes, compared with the IMRT technique. Moreover, it could reduce the MU and delivery time effectively.

The impact of introducing intensity modulated radiotherapy into routine clinical practice.

Science.gov (United States)

Miles, Elizabeth A; Clark, Catharine H; Urbano, M Teresa Guerrero; Bidmead, Margaret; Dearnaley, David P; Harrington, Kevin J; A'Hern, Roger; Nutting, Christopher M

2005-12-01

Intensity modulated radiotherapy (IMRT) at the Royal Marsden Hospital London was introduced in July 2001. Treatment delivery was dynamic using a single-phase technique. Concerns were raised regarding increased clinical workload due to introduction of new technology. The potential increased use of resources was assessed. IMRT patient selection was within guidelines of clinical trials and included patients undergoing prostate plus pelvic lymph node (PPN) irradiation and head and neck cancer (HNC) treatment. Patient planning, quality assurance and treatment times were collected for an initial IMRT patient group. A comparative group of patients with advanced HNC undergoing two- or three-phase conventional radiotherapy, requiring matched photon and electron fields, were also timed. The median overall total planning time for IMRT was greater for HNC patients compared to the PPN cohort. For HNC the overall IMRT planning time was significantly longer than for conventional. The median treatment time for conventional two- or three-phase HNC treatments, encompassing similar volumes to those treated with IMRT, was greater than that for the IMRT HNC patient cohort. A reduction in radiographer man hours per patient of 4.8h was recorded whereas physics time was increased by 4.9h per patient. IMRT currently increases overall planning time. Additional clinician input is required for target volume localisation. Physics time is increased, a significant component of this being patient specific QA. Radiographer time is decreased. For HNC a single phase IMRT treatment has proven to be more efficient than a multiple phase conventional treatment. IMRT has been integrated smoothly and efficiently into the existing treatment working day. This preliminary study suggests that IMRT could be a routine treatment with efficient use of current radiotherapy resources.

Basis for new strategies in postoperative radiotherapy of bronchogenic carcinoma

International Nuclear Information System (INIS)

Choi, N.C.H.; Grillo, H.C.; Gardiello, M.; Scannel, J.G.; Wilkins, E.W. Jr.

1980-01-01

In order to improve our understanding of the role of postoperative radiotherapy and to search for new strategies in the management of N 1 , N 2 , T 3 stage carcinoma of the lung, we analyzed results of treatment in 148 of 166 patients who were registered at the Massachusetts General Hospital Tumor Registry from 1971 to 1977 with a pathological diagnosis of N 1 , N 2 , T 3 carcinoma of the lung after pulmonary resection. Ninety-three patients received postoperative radiotherapy and another 55 were followed without further treatment. Patients with adenocarcinoma showed significant improvement of survival by postoperative radiotherapy; actuarial NED (no evidence of disease) survival rates were 85% and 51% at 1 year, and 43% and 8% at 5 years for S + RT (patients treated with surgery plus postoperative radiotherapy) and S (patients treated with surgery only) groups, respectively, (P 2 , T 3 stages. Regional recurrence was the most common failure in squamous cell carcinoma; 76% (13/17) and 45% (10/22) of all failures were in the regional area in S and S + RT groups. Regional failure in S + RT group was noted with radiation dose up to 5000 rad (TDF 82) which suggests radiation dose higher than 5000 rad in future trial

DARS: a phase III randomised multicentre study of dysphagia- optimised intensity- modulated radiotherapy (Do-IMRT) versus standard intensity- modulated radiotherapy (S-IMRT) in head and neck cancer

International Nuclear Information System (INIS)

Petkar, Imran; Rooney, Keith; Roe, Justin W. G.; Patterson, Joanne M.; Bernstein, David; Tyler, Justine M.; Emson, Marie A.; Morden, James P.; Mertens, Kathrin; Miles, Elizabeth; Beasley, Matthew; Roques, Tom; Bhide, Shreerang A.; Newbold, Kate L.; Harrington, Kevin J.; Hall, Emma; Nutting, Christopher M.

2016-01-01

Persistent dysphagia following primary chemoradiation (CRT) for head and neck cancers can have a devastating impact on patients’ quality of life. Single arm studies have shown that the dosimetric sparing of critical swallowing structures such as the pharyngeal constrictor muscle and supraglottic larynx can translate to better functional outcomes. However, there are no current randomised studies to confirm the benefits of such swallow sparing strategies. The aim of Dysphagia/Aspiration at risk structures (DARS) trial is to determine whether reducing the dose to the pharyngeal constrictors with dysphagia-optimised intensity- modulated radiotherapy (Do-IMRT) will lead to an improvement in long- term swallowing function without having any detrimental impact on disease-specific survival outcomes. The DARS trial (CRUK/14/014) is a phase III multicentre randomised controlled trial (RCT) for patients undergoing primary (chemo) radiotherapy for T1-4, N0-3, M0 pharyngeal cancers. Patients will be randomised (1:1 ratio) to either standard IMRT (S-IMRT) or Do-IMRT. Radiotherapy doses will be the same in both groups; however in patients allocated to Do-IMRT, irradiation of the pharyngeal musculature will be reduced by delivering IMRT identifying the pharyngeal muscles as organs at risk. The primary endpoint of the trial is the difference in the mean MD Anderson Dysphagia Inventory (MDADI) composite score, a patient-reported outcome, measured at 12 months post radiotherapy. Secondary endpoints include prospective and longitudinal evaluation of swallow outcomes incorporating a range of subjective and objective assessments, quality of life measures, loco-regional control and overall survival. Patients and speech and language therapists (SLTs) will both be blinded to treatment allocation arm to minimise outcome-reporting bias. DARS is the first RCT investigating the effect of swallow sparing strategies on improving long-term swallowing outcomes in pharyngeal cancers. An integral

Intensity-modulated radiation therapy.

Science.gov (United States)

Goffman, Thomas E; Glatstein, Eli

2002-07-01

Intensity-modulated radiation therapy (IMRT) is an increasingly popular technical means of tightly focusing the radiation dose around a cancer. As with stereotactic radiotherapy, IMRT uses multiple fields and angles to converge on the target. The potential for total dose escalation and for escalation of daily fraction size to the gross cancer is exciting. The excitement, however, has greatly overshadowed a range of radiobiological and clinical concerns.

Prophylactic post-operative radiotherapy prevents heterotopic ossification following traumatic acetabular fracture

International Nuclear Information System (INIS)

Meyer, Joseph T.; Hixson, William C.; Jennelle, Richard L. S.; Alonso, Jorge E.; Raben, David; Spencer, Sharon S.; Kim, Robert Y.

1996-01-01

Purpose/Objective: To determine the effect of post-operative radiation on the incidence of heterotopic ossification following traumatic acetabular fracture. Materials and Methods: A retrospective analysis was performed of the medical records and radiographs of all patients who received prophylactic radiotherapy to prevent heterotopic ossification. These results were compared to a similar group of patients receiving no prophylactic radiotherapy following traumatic acetabular fracture. Between 1987 and 1994, sixty-six patients received prophylactic radiotherapy to prevent heterotopic ossification. Results: Thirty-six patients (55%) received radiotherapy following operative repair of a traumatic acetabular fracture (median follow-up: 210 days). Three dose schedules were utilized: (28(36)) (77.8%) received 700 cGy/1 fx, (2(36)) (5.5%) 800 cGy/1 fx, and (6(36)) (16.7%) 1000 cGy/5 fxs. These patients were retrospectively compared with thirty-four patients who received similar operative management of traumatic acetabular fractures without post-operative radiotherapy (median follow-up: 378 days). Of the patients with heterotopic ossification, 96% developed it within 180 days. Complications and delayed wound healing rates were not significantly different in patients treated with or without post-operative radiotherapy, 6.4% and 6.3% respectively (p=0.49). The incidence of heterotopic ossification at last follow-up in patients treated with and without post-operative radiotherapy was (5(36)) (13.9%) and (19(34)) (55.9%), respectively (p=0.000332). For all patients, type of surgical approach was associated with development of heterotopic ossification: posterior, (7(38)) (18.4%), ilio-inguinal (1(3)) (33.3%), tri-radiate (13(19)) (68.4%), p=.000511. In patients receiving post-operative radiotherapy, variables associated with heterotopic ossification included dose (p=.00962), injury-to-radiation interval (p=.0038), and surgery-to-radiation interval (p=.0238). Fifty percent ((3

Cervix carcinomas: place of intensity-modulated radiotherapy; Les cancers du col uterin: place de la radiotherapie avec modulation d'intensite

Energy Technology Data Exchange (ETDEWEB)

Barillot, I. [Centre Regional Universitaire de Cancerologie H.S.-Kaplan, Hopital Bretonneau, CHU de Tours, 37 - Tours (France); Universite Francois-Rabelais, 37 - Tours (France)

2009-10-15

While indications of modulated intensity radiation therapy (I.M.R.T.) are perfectly defined in head and neck and prostate cancer patients, this technique remains under evaluation for gynecologic tumours. The implementation of conformal three dimensional radiotherapy in the late 1990 has been the first important step for optimisation of treatment of cervix carcinomas, as it permitted a better target coverage with a significant reduction of the bladder dose. However, this technique often leads to an irradiation of a larger volume of rectum in locally advanced stages and could only spare a limited amount of intestine. I.R.M.T. is one of the optimisation methods potentially efficient for a better sparing of digestive tract during irradiation of cervix carcinomas. The aim of this literature review is to provide the arguments supporting this hypothesis, and to define the place of this technique for dose escalation. (authors)

The impact of introducing intensity modulated radiotherapy into routine clinical practice

International Nuclear Information System (INIS)

Miles, Elizabeth A.; Clark, Catharine H.; Urbano, M. Teresa Guerrero; Bidmead, Margaret; Dearnaley, David P.; Harrington, Kevin J.; A'Hern, Roger; Nutting, Christopher M.

2005-01-01

Background and purpose: Intensity modulated radiotherapy (IMRT) at Royal Marsden Hospital London was introduced in July 2001. Treatment delivery was dynamic using a single-phase technique. Concerns were raised regarding increased clinical workload due to introduction of new technology. The potential increased use of resources was assessed. Patients and methods: IMRT patient selection was within guidelines of clinical trials and included patients undergoing prostate plus pelvic lymph node (PPN) irradiation and head and neck cancer (HNC) treatment. Patient planning, quality assurance and treatment times were collected for an initial IMRT patient group. A comparative group of patients with advanced HNC undergoing two- or three-phase conventional radiotherapy, requiring matched photon and electron fields, were also timed. Results: The median overall total planning time for IMRT was greater for HNC patients compared to the PPN cohort. For HNC the overall IMRT planning time was significantly longer than for conventional. The median treatment time for conventional two- or three-phase HNC treatments, encompassing similar volumes to those treated with IMRT, was greater than that for the IMRT HNC patient cohort. A reduction in radiographer man hours per patient of 4.8 h was recorded whereas physics time was increased by 4.9 h per patient. Conclusions: IMRT currently increases overall planning time. Additional clinician input is required for target volume localisation. Physics time is increased, a significant component of this being patient specific QA. Radiographer time is decreased. For HNC a single phase IMRT treatment has proven to be more efficient than a multiple phase conventional treatment. IMRT has been integrated smoothly and efficiently into the existing treatment working day. This preliminary study suggests that IMRT could be a routine treatment with efficient use of current radiotherapy resources

Comparison of long-term survival and toxicity of simultaneous integrated boost vs conventional fractionation with intensity-modulated radiotherapy for the treatment of nasopharyngeal carcinoma

Directory of Open Access Journals (Sweden)

Tao HM

2016-03-01

Full Text Available Hengmin Tao,1,2 Yumei Wei,1 Wei Huang,1 Xiujuan Gai,1,2 Baosheng Li11Department of 6th Radiation Oncology, Shandong Cancer Hospital and Institute, 2School of Medicine and Life Sciences, Jinan University-Shandong Academy of Medical Sciences, Jinan, People’s Republic of ChinaAim: In recent years, the intensity-modulated radiotherapy with simultaneous integrated boost (IMRT-SIB and intensity-modulated radiotherapy with conventional fractionation (IMRT-CF have been involved in the treatment of nasopharyngeal carcinoma (NPC. However, the potential clinical effects and toxicities are still controversial.Methods: Here, 107 patients with biopsy-proven locally advanced NPC between March 2004 and January 2011 were enrolled in the retrospective study. Among them, 54 patients received IMRT-SIB, and 53 patients received IMRT-CF. Subsequently, overall survival (OS, 5-year progression-free survival (PFS, 5-year locoregional recurrence-free survival (LRFS, and relevant toxicities were analyzed.Results: In the present study, all patients completed the treatment, and the overall median follow-up time was 80 months (range: 8–126 months. The 5-year OS analysis revealed no significant difference between the IMRT-SIB and IMRT-CF groups (80.9% vs 80.5%, P=0.568. In addition, there were also no significant between-group differences in 5-year PFS (73.3% vs 74.4%, P=0.773 and 5-year LRFS (88.1% vs 90.8%, P=0.903. Notably, the dose to critical organs (spinal cord, brainstem, and parotid gland in patients treated by IMRT-CF was significantly lower than that in patients treated by IMRT-SIB (all P<0.05.Conclusion: Both IMRT-SIB and IMRT-CF techniques are effective in treating locally advanced NPC, with similar OS, PFS, and LRFS. However, IMRT-CF has more advantages than IMRT-SIB in protecting spinal cord, brainstem, and parotid gland from acute and late toxicities, such as xerostomia. Further prospective study is warranted to confirm our findings.Keywords: intensity-modulated

Intensity-Modulated Radiotherapy for Craniospinal Irradiation: Target Volume Considerations, Dose Constraints, and Competing Risks

International Nuclear Information System (INIS)

Parker, William; Filion, Edith; Roberge, David; Freeman, Carolyn R.

2007-01-01

Purpose: To report the results of an analysis of dose received to tissues and organs outside the target volume, in the setting of spinal axis irradiation for the treatment of medulloblastoma, using three treatment techniques. Methods and Materials: Treatment plans (total dose, 23.4 Gy) for a standard two-dimensional (2D) technique, a three-dimensional (3D) technique using a 3D imaging-based target volume, and an intensity-modulated radiotherapy (IMRT) technique, were compared for 3 patients in terms of dose-volume statistics for target coverage, as well as organ at risk (OAR) and overall tissue sparing. Results: Planning target volume coverage and dose homogeneity was superior for the IMRT plans for V 95% (IMRT, 100%; 3D, 96%; 2D, 98%) and V 107% (IMRT, 3%; 3D, 38%; 2D, 37%). In terms of OAR sparing, the IMRT plan was better for all organs and whole-body contour when comparing V 10Gy , V 15Gy , and V 20Gy . The 3D plan was superior for V 5Gy and below. For the heart and liver in particular, the IMRT plans provided considerable sparing in terms of V 10Gy and above. In terms of the integral dose, the IMRT plans were superior for liver (IMRT, 21.9 J; 3D, 28.6 J; 2D, 38.6 J) and heart (IMRT, 9 J; 3D, 14.1J; 2D, 19.4 J), the 3D plan for the body contour (IMRT, 349 J; 3D, 337 J; 2D, 555 J). Conclusions: Intensity-modulated radiotherapy is a valid treatment option for spinal axis irradiation. We have shown that IMRT results in sparing of organs at risk without a significant increase in integral dose

Hypofractionated Intensity-Modulated Radiotherapy for Carcinoma of the Prostate: Analysis of Toxicity

International Nuclear Information System (INIS)

Coote, Joanna H.; Wylie, James P.; Cowan, Richard A.; Logue, John P.; Swindell, Ric; Livsey, Jacqueline E.

2009-01-01

Purpose: Dose escalation for prostate cancer improves biological control but with a significant increase in late toxicity. Recent estimates of low α/β ratio for prostate cancer suggest that hypofractionation may result in biological advantage. Intensity-modulated radiotherapy (IMRT) should enable dose escalation to the prostate while reducing toxicity to local organs. We report late toxicity data of a hypofractionated IMRT regime. Methods and Materials: Eligible men had T2-3N0M0 adenocarcinoma prostate, and either Gleason score ≥ 7 or prostate-specific antigen 20-50 ng/L. Patients received 57-60 Gy to prostate in 19-20 fractions using five-field IMRT. All received hormonal therapy for 3 months before radiotherapy to a maximum of 6 months. Toxicity was assessed 2 years postradiotherapy using the RTOG criteria, LENT/SOMA, and UCLA prostate index assessment tools. Results: Acute toxicity was favorable with no RTOG Grade 3 or 4 toxicity. At 2 years, there was 4% Grade 2 bowel and 4.25% Grade 2 bladder toxicity. There was no Grade 3 or 4 bowel toxicity; one patient developed Grade 3 bladder toxicity. UCLA data showed a slight improvement in urinary function at 2 years compared with pretreatment. LENT/SOMA assessments demonstrated general worsening of bowel function at 2 years. Patients receiving 60 Gy were more likely to develop problems with bowel function than those receiving 57 Gy. Conclusions: These data demonstrate that hypofractionated radiotherapy using IMRT for prostate cancer is well tolerated with minimal late toxicity at 2 years posttreatment. Ongoing studies are looking at the efficacy of hypofractionated regimes with respect to biological control.

Is "pelvic radiation disease" always the cause of bowel symptoms following prostate cancer intensity-modulated radiotherapy?

Science.gov (United States)

Min, Myo; Chua, Benjamin; Guttner, Yvonne; Abraham, Ned; Aherne, Noel J; Hoffmann, Matthew; McKay, Michael J; Shakespeare, Thomas P

2014-02-01

Pelvic radiation disease (PRD) also widely known as "radiation proctopathy" is a well recognised late side-effect following conventional prostate radiotherapy. However, endoscopic evaluation and/or specialist referral for new or persistent post-prostate radiotherapy bowel symptoms is not routine and serious diagnoses may potentially be missed. Here we report a policy of endoscopic evaluation of bowel symptoms persisting >90 days post radiotherapy for prostate cancer. A consecutive series of 102 patients who had radical prostate intensity-modulated radiotherapy (IMRT)/image-guided radiotherapy (IGRT) and who had new or ongoing bowel symptoms or positive faecal occult blood tests (FOBT) on follow up visits more than three months after treatment, were referred for endoscopic examination. All but one (99%) had full colonoscopic investigation. Endoscopic findings included gastric/colonic/rectal polyps (56%), diverticular disease (49%), haemorrhoids (38%), radiation proctopathy (29%), gastritis/oesophagitis (8%) and rarer diagnoses, including bowel cancer which was found in 3%. Only four patients (4%) had radiation proctopathy without associated pathology and 65 patients (63%) had more than one diagnosis. If flexible sigmoidoscopy alone were used, 36.6% of patients and 46.6% patients with polyp(s) would have had their diagnoses missed. Our study has shown that bowel symptoms following prostate IMRT/IGRT are due to numerous diagnoses other than PRD, including malignancy. Routine referral pathways should be developed for endoscopic evaluation/specialist review for patients with new or persistent bowel symptoms (or positive FOBT) following prostate radiotherapy. This recommendation should be considered for incorporation into national guidelines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dosimetric complication probability and acoustic analysis of vocal cord region in oropharyngeal carcinoma treated with voice-sparing intensity modulated radiotherapy

International Nuclear Information System (INIS)

Jain, S.; Gupta, T.; Agarwal, J.P.; Baccher, G.; Shrivastava, S.K.; Reenadevi; Master, J.

2008-01-01

Radiation to larynx has long been associated with speech and voice dysfunction. The objective is to study dosimetric parameters and complication probability of vocal cord region (VCR) and the effect of voice-sparing (VS) in the patients treated with intensity modulated radiotherapy (IMRT). The secondary objective is to describe the post-radiation acoustic voice characteristics and correlate them with the dosimetric parameters. (author)

Quality of life in patients with nasopharyngeal carcinoma after intensity modulated radiotherapy

International Nuclear Information System (INIS)

Ma Liqin; Zhang Yu; Pan Jianji; Yang Ling; Kong Xiangquan; Ni Xiaolei

2009-01-01

Objective: To analyze the status of quality of life (QOL) and the related factors in patients with nasopharyngeal carcinoma (NPC) after radiotherapy, and to explore the significance of intensity modulated radiotherapy (IMRT) in decreasing side effects and improving QOL. Methods: A questionnaire including 35 items was designed according to EORTC QLQ-30 and the related symptoms and side effects of NPC. 142 NPC patients surviving with disease-free after radiotherapy were surveyed for the evaluation of QOL. The median follow-up was 25 months. The information of social demography and clinical details were collected. The patients were divided into IMRT group (75 patients) and conventional radiotherapy (CRT) group (67 patients). A statistical software package SAS 8.1 was used to compare the marks of QOL between the groups and analyze the influencing factors. Results: In IMRT group and CRT group, the marks of affective cognitive domain were 82.8 ± 14.7 and 77.5 ± 16.0 (t=2.07, P=0.040); and the marks of disease and treatment-related symptoms, and reactive domain were 78.9 ± 10.3 and 69.8 ± 13.3 (t=4.59, P= 0.000). The marks were significantly different in xerostomia, trismus, deglutitoy choke, hoarseness, restriction of neck movement and dysphagia (P<0.05). Of the influencing factors of QOL, the domain of body function was sex (regression coefficient was -4.692), the self-evaluation of total QOL were follow-up time and educational background (regression coefficients were -0.618 and 12.316, respectively), the financial status was family monthly income per capita (regression coefficient was -11.133), and the disease and treatment-related symptoms and reactive domain were group (techniques of radiation) and age (regression coefficients were -9.384 and -5.853, respectively). Conclusions: IMRT could improve the QOL through decreasing the side effects of patients with NPC including xerostomia, trismus, restriction of neck movement and dysphagia. Sex, age, family monthly

Intensity modulated radiotherapy (IMRT) for patients of the Brazilian unified health system (SUS): an analysis of 508 treatments two years after the technique implementation

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Oliveira, Harley Francisco de; Trevisan, Felipe Amstalden; Bighetti, Viviane Marques; Guimaraes, Flavio da Silva; Amaral, Leonardo Lira; Barbi, Gustavo Lazaro; Borges, Leandro Federiche; Peria, Fernanda Maris, E-mail: harley@fmrp.usp.br [Universidade de Sao Paulo (FMRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina

2014-11-15

Objective: the offering of high-technology radiotherapy to the population assisted by the Brazilian unified health system (SUS) is limited since it is not included in the system’s list of procedures and, many times, because of the insufficient installed capacity and lack of specialized human resources. Thus the access to intensity-modulated radiotherapy (IMRT) is restricted to few centers in Brazil. The present study is aimed at presenting the characteristics of the first 508 cases treated with IMRT during the first years after the technique implementation in a university hospital. Materials and methods: the first consecutive 508 cases of IMRT treatment completed in the period from May/2011 to September/2013 were reviewed. Static multi leaf was the technique employed. Results: amongst 4,233 treated patients, 12.5% were submitted to IMRT. Main indications for the treatment included cancers located in the skull, head and neck and prostate. Intensity modulated radiotherapy was utilized in about 30% of cranial and 50% of prostate treatments. Treatment toxicity was observed in 4% of the patients. Conclusion: because of restricted access to radiotherapy in addition to lack of coverage for the procedure, IMRT indications for SUS patients should be based on institutional clinical protocols, with special attention to the reduction of toxicity. (author)

Investigation of the added value of high-energy electrons in intensity-modulated radiotherapy: four clinical cases

International Nuclear Information System (INIS)

Korevaar, Erik W.; Huizenga, Henk; Loef, Johan; Stroom, Joep C.; Leer, Jan Willem H.; Brahme, Anders

2002-01-01

Purpose: Intensity-modulated radiotherapy (IMRT) with photon beams is currently pursued in many clinics. Theoretically, inclusion of intensity- and energy-modulated high-energy electron beams (15-50 MeV) offers additional possibilities to improve radiotherapy treatments of deep-seated tumors. In this study the added value of high-energy electron beams in IMRT treatments was investigated. Methods and Materials: In a comparative treatment planning study, conventional treatment plans and various types of IMRT plans were constructed for four clinical cases (cancer of the bladder, pancreas, chordoma of the sacrum, and breast). The conventional plans were used for the actual treatment of the patients. The IMRT plans were optimized using the Orbit optimization code (Loef et al., 2000) with a radiobiologic objective function. The IMRT plans were either photon or combined electron and photon beam plans, with or without dose homogeneity constraints assuming standard or increased radiosensitivities of organs at risk. Results: Large improvements in expected treatment outcome are found using IMRT plans compared to conventional plans, but differences in tumor control probability (TCP) and normal tissue complication probabilities (NTCP) values between IMRT plans with and without electrons are small. However, the use of electrons improves the dose-volume histograms for organs at risk, especially at lower dose levels (e.g., 0-40 Gy). Conclusions: This preliminary study indicates that addition of higher energy electrons to IMRT can only marginally improve treatment outcome for the selected cases. The dose-volume histograms of organs at risk show improvements for IMRT with higher energy electrons, which may reduce tumor induction but does not substantially reduce NTCP

Target volume delineation for head and neck cancer intensity-modulated radiotherapy; Delineation des volumes cibles des cancers des voies aerodigestives superieures en radiotherapie conformationnelle avec modulation d'intensite

Energy Technology Data Exchange (ETDEWEB)

Lapeyre, M.; Toledano, I.; Bourry, N. [Departement de radiotherapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France); Bailly, C. [Unite de radiodiagnostic, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France); Cachin, F. [Unite de medecine nucleaire, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1 (France)

2011-10-15

This article describes the determination and the delineation of the target volumes for head-and-neck cancers treated with intensity-modulated radiotherapy (IMRT). The delineation of the clinical target volumes (CTV) on the computerized tomography scanner (CT scan) requires a rigorous methodology due to the complexity of head-and-neck anatomy. The clinical examination with a sketch of pretreatment tumour extension, the surgical and pathological reports and the adequate images (CT scan, magnetic resonance imaging and fluorodeoxyglucose positron emission tomography) are necessary for the delineation. The target volumes depend on the overall strategy: sequential IMRT or simultaneous integrated boost-IMRT (SIB-IMRT). The concept of selectivity of the potential subclinical disease near the primary tumor and the selection of neck nodal targets are described according to the recommendations and the literature. The planing target volume (PTV), mainly reflecting setup errors (random and systematic), results from a uniform 4-5 mm expansion around the CTV. We propose the successive delineation of: (1) the gross volume tumour (GTV); (2) the 'high risk' CTV1 around the GTV or including the postoperative tumour bed in case of positive margins or nodal extra-capsular spread (65-70 Gy in 30-35 fractions); (3) the CTV2 'intermediate risk' around the CTV1 for SIB-IMRT (59-63 Gy in 30-35 fractions); (4) the 'low-risk' CTV3 (54-56 Gy in 30-35 fractions); (5) the PTVs. (authors)

Accelerated Intensity-Modulated Radiotherapy to Breast in Prone Position: Dosimetric Results

International Nuclear Information System (INIS)

De Wyngaert, J. Keith; Jozsef, Gabor; Mitchell, James; Rosenstein, Barry; Formenti, Silvia C.

2007-01-01

Purpose: To report the physics and dosimetry results of a trial of accelerated intensity-modulated radiotherapy to the whole breast with a concomitant boost to the tumor bed in patients treated in the prone position. Methods and Materials: Patients underwent computed tomography planning and treatment in the prone position on a dedicated treatment platform. The platform has an open aperture on the side to allow for the index breast to fall away from the chest wall. Noncontrast computed tomography images were acquired at 2.5- or 3.75-mm-thick intervals, from the level of the mandible to below the diaphragm. A dose of 40.5 Gy was delivered to the entire breast at 2.7-Gy fractions in 15 fractions. An additional dose of 0.5 Gy was delivered as a concomitant boost to the lumpectomy site, with a 1-cm margin, using inverse planning, for a total dose of 48 Gy in 15 fractions. No more than 10% of the heart and lung volume was allowed to receive >18 and >20 Gy, respectively. Results: Between September 2003 and August 2005, 91 patients were enrolled in the study. The median volume of heart that received ≥18 Gy was 0.5%, with a maximal value of 4.7%. The median volume of ipsilateral lung that received ≥20 Gy was 0.8%, with a maximum of 7.2%. Conclusion: This technique for whole breast radiotherapy is feasible and enables an accelerated regimen in the prone position while sparing the lung and heart

A dosimetric comparison of fan-beam intensity modulated radiotherapy with gamma knife stereotactic radiosurgery for treating intermediate intracranial lesions

International Nuclear Information System (INIS)

Ma Lijun; Xia Ping; Verhey, Lynn J.; Boyer, Arthur L.

1999-01-01

Purpose: To compare and evaluate treatment plans for the fan-beam intensity modulated radiotherapy and the Gamma Knife radiosurgery for treating medium-size intracranial lesions (range 4-25 cm 3 ). Methods and Materials: Treatment plans were developed for the Leksell Gamma Knife and a fan-beam inverse treatment planning system for intensity modulated radiotherapy. Treatment plan comparisons were carried out using dose-volume histogram (DVH), tissue-volume ratio (TVR), and maximum dose to the prescription dose (MDPD) ratio. The study was carried out for both simulated targets and clinical targets with irregular shapes and at different locations. Results: The MDPD ratio was significantly greater for the Gamma Knife plans than for the fan-beam IMRT plans. The Gamma Knife plans produced equivalent TVR values to the fan-beam IMRT plans. Based on the DVH comparison, the fan-beam IMRT delivered significantly more dose to the normal brain tissue than the Gamma Knife. The results of the comparison were found to be insensitive to the target locations. Conclusion: The Gamma Knife is better than the fan-beam IMRT in sparing normal brain tissue while producing equivalent tumor dose conformity for treating medium-size intracranial lesions. However, the target dose homogeneity is significantly better for the fan-beam IMRT than for the Gamma Knife

Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: Dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

International Nuclear Information System (INIS)

Wang, Xin; Li, Guangjun; Zhang, Yingjie; Bai, Sen; Xu, Feng; Wei, Yuquan; Gong, Youling

2013-01-01

To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V 20/30 , and mean dose of the left kidney, as well as the V 20/30 of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V 20 of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6 Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future

Toxicity after intensity-modulated, image-guided radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Flentje, Michael; Guckenberger, Matthias; Ok, Sami; Polat, Buelent; Sweeney, Reinhart A.

2010-01-01

Purpose: To evaluate toxicity after dose-escalated radiotherapy for prostate cancer using intensity-modulated treatment planning (IMRT) and image-guided treatment (IGRT) delivery. Patients and Methods: 100 patients were treated with simultaneous integrated boost (SIB) IMRT for prostate cancer: doses of 76.23 Gy and 60 Gy in 33 fractions were prescribed to the prostate and the seminal vesicles, respectively, for intermediate- and high-risk patients (n = 74). The total dose was 73.91 Gy in 32 fractions for low-risk patients and after transurethral resection of the prostate (n = 26). The pelvic lymphatics were treated with 46 Gy in 25 fractions in patients with high risk of lymph node metastases using an SIB to the prostate (n = 25). IGRT was practiced with cone-beam computed tomography. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity was evaluated prospectively (CTCAE v3.0). Results: Treatment was completed as planned by all patients. Acute GI and GU toxicity grade ≥ 2 was observed in 12% and 42% of the patients, respectively, with 4% suffering from GU toxicity grade 3. 6 weeks after treatment, the incidence of acute toxicity grade ≥ 2 had decreased to 12%. With a median follow-up of 26 months, late GI and GU toxicity grade ≥ 2 was seen in 1.5% and 7.7% of the patients at 24 months. Four patients developed late toxicity grade 3 (GI n = 1; GU n = 3). Presence of acute GI and GU toxicity was significantly associated with late GI (p = 0.0007) and GU toxicity (p = 0.006). Conclusion: High-dose radiotherapy for prostate cancer using IMRT and IGRT resulted in low rates of acute toxicity and preliminary results of late toxicity are promising. (orig.)

Toxicity after intensity-modulated, image-guided radiotherapy for prostate cancer

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Flentje, Michael [Dept. of Radiotherapy, Univ. Hospital Wuerzburg (Germany); Guckenberger, Matthias; Ok, Sami; Polat, Buelent; Sweeney, Reinhart A.

2010-10-15

Purpose: To evaluate toxicity after dose-escalated radiotherapy for prostate cancer using intensity-modulated treatment planning (IMRT) and image-guided treatment (IGRT) delivery. Patients and Methods: 100 patients were treated with simultaneous integrated boost (SIB) IMRT for prostate cancer: doses of 76.23 Gy and 60 Gy in 33 fractions were prescribed to the prostate and the seminal vesicles, respectively, for intermediate- and high-risk patients (n = 74). The total dose was 73.91 Gy in 32 fractions for low-risk patients and after transurethral resection of the prostate (n = 26). The pelvic lymphatics were treated with 46 Gy in 25 fractions in patients with high risk of lymph node metastases using an SIB to the prostate (n = 25). IGRT was practiced with cone-beam computed tomography. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity was evaluated prospectively (CTCAE v3.0). Results: Treatment was completed as planned by all patients. Acute GI and GU toxicity grade {>=} 2 was observed in 12% and 42% of the patients, respectively, with 4% suffering from GU toxicity grade 3. 6 weeks after treatment, the incidence of acute toxicity grade {>=} 2 had decreased to 12%. With a median follow-up of 26 months, late GI and GU toxicity grade {>=} 2 was seen in 1.5% and 7.7% of the patients at 24 months. Four patients developed late toxicity grade 3 (GI n = 1; GU n = 3). Presence of acute GI and GU toxicity was significantly associated with late GI (p = 0.0007) and GU toxicity (p = 0.006). Conclusion: High-dose radiotherapy for prostate cancer using IMRT and IGRT resulted in low rates of acute toxicity and preliminary results of late toxicity are promising. (orig.)

Comparative Analysis between preoperative Radiotherapy and postoperative Radiotherapy in Clinical Stage I and II Endometrial Carcinoma

International Nuclear Information System (INIS)

Keum, Ki Chang; Lee, Chang Geol; Chung, Eun Ji; Lee, Sang Wook; Kim, Woo Cheol; Chang, Sei Kyung; Oh, Young Taek; Suh, Chang Ok; Kim, Gwi Eon

1995-01-01

Purpose : To obtain the optical treatment method in patients with endometrial carcinoma(clinical stage FIGO I, II) by comparative analysis between preoperative radiotherapy(pre-op R) and postoperative radiotherapy(post-op RT). Materials and Methods : A retrospective review of 62 endometrial carcinoma patients referred to the Yonsei Cancer Center for radiotherapy between 1985 and 1991 was undertaken. Of 62 patients, 19 patients(Stage I; 12 patients, Stage II; 7 patients) received pre-op RT before TAH(Total Abdominal Hysterectomy) and BSO(Bilateral Salphingoophorectomy) (Group 1) and 43 patients( Stage 1; 32 patients, Stage 2; 11 patients) received post-op RT after TAH and BSO (Group 2). Pre-op irradiation was given 4-6 weeks prior to surgery and post-op RT was administered on 4-5 weeks following surgery. All patients exept 1 patient(Group2; ICR alone) received external irradiation. Seventy percent(13/19) of pre-op RT group and 54 percent(23/42) of post-op RT group received external pelvic irradiation and intracavitary radiation therapy(ICR). External radiation dose was 39.6-55Gy(median 45Gy) in 5-6 week through opposed AP/PA fields or 4-field box technique treating daily, five days per week, 180cGy per fraction. ICR doses were prescribed to point A(20-39.6 Gy, median 39Gy) in Group 1 and 0.5cm depth from vaginal surface (18-30 Gy, median 21Gy) in Group2. Results : The overall 5 year survival rate was 95%. No survival difference between pre-op and post-op RT group.(89.3% vs 97.7%, p>0.1) There was no survival difference by stage, grade and histology between two groups. The survival rate was not affected by presence of residual tumor of surgical specimen after pre-op RT in Group 1(p>0.1), but affected by presence of lymph node metastasis in post-op RT group(p<0.5). The complication rate of pre-op RT group was higher than post-op RT.(16% vs 5%) Conclusion : Post-op radiotherapy offers the advantages of accurate surgical-pathological staging and low complication rate

A comparison of conformal and intensity-modulated techniques for oesophageal radiotherapy

International Nuclear Information System (INIS)

Nutting, Christopher M.; Bedford, James L.; Cosgrove, Vivian P.; Tait, Diana M.; Dearnaley, David P.; Webb, Steve

2001-01-01

Background and purpose: To investigate the potential of intensity-modulated radiotherapy (IMRT) to reduce lung irradiation in the treatment of oesophageal carcinoma with radical radiotherapy. Materials and methods: A treatment planning study was performed to compare two-phase conformal radiotherapy (CFRT) with IMRT in five patients. The CFRT plans consisted of anterior, posterior and bilateral posterior oblique fields, while the IMRT plans consisted of either nine equispaced fields (9F), or four fields (4F) with orientations equal to the CFRT plans. IMRT plans with seven, five or three equispaced fields were also investigated in one patient. Treatment plans were compared using dose-volume histograms and normal tissue complication probabilities. Results: The 9F IMRT plan was unable to improve on the homogeneity of dose to the planning target volume (PTV), compared with the CFRT plan (dose range, 16.9±4.5 (1 SD) vs. 12.4±3.9%; P=0.06). Similarly, the 9F IMRT plan was unable to reduce the mean lung dose (11.7±3.2 vs. 11.0±2.9 Gy; P=0.2). Similar results were obtained for seven, five and three equispaced fields in the single patient studied. The 4F IMRT plan provided comparable PTV dose homogeneity with the CFRT plan (11.8±3.3 vs. 12.4±3.9%; P=0.6), with reduced mean lung dose (9.5±2.3 vs 11.0±2.9 Gy; P=0.001). Conclusions: IMRT using nine equispaced fields provided no improvement over CFRT. This was because the larger number of fields in the IMRT plan distributed a low dose over the entire lung. In contrast, IMRT using four fields equal to the CFRT fields offered an improvement in lung sparing. Thus, IMRT with a few carefully chosen field directions may lead to a modest reduction in pneumonitis, or allow tumour dose escalation within the currently accepted lung toxicity

Potential clinical efficacy of intensity-modulated conformal therapy

International Nuclear Information System (INIS)

Meeks, Sanford L.; Buatti, John M.; Bova, Francis J.; Friedman, William A.; Mendenhall, William M.; Zlotecki, Robert A.

1998-01-01

Purpose: The purpose of this study was to examine the potential benefit of using intensity-modulated conformal therapy for a variety of lesions currently treated with stereotactic radiosurgery or conventional radiotherapy. Methods and Materials: Intensity-modulated conformal treatment plans were generated for small intracranial lesions, as well as head and neck, lung, breast, and prostate cases, using the Peacock Plan[reg] treatment-planning system (Nomos Corporation). For small intracranial lesions, intensity-modulated conformal treatment plans were compared with stereotactic radiosurgery treatment plans generated for patient treatment at the University of Florida Shands Cancer Center. For other sites (head and neck, lung, breast, and prostate), plans generated using the Peacock Plan[reg] were compared with conventional treatment plans, as well as beam's-eye-view conformal treatment plans. Plan comparisons were accomplished through conventional qualitative review of two-dimensional (2D) dose distributions in conjunction with quantitative techniques, such as dose-volume histograms, dosimetric statistics, normal tissue complication probabilities, tumor control probabilities, and objective numerical scoring. Results: For small intracranial lesions, there is little difference between intensity-modulated conformal treatment planning and radiosurgery treatment planning in the conformation of high isodose lines with the target volume. However, stereotactic treatment planning provides a steeper dose gradient outside the target volume and, hence, a lower normal tissue toxicity index. For extracranial sites, objective numerical scores for beam's-eye-view and intensity-modulated conformal planning techniques are superior to scores for conventional treatment plans. The beam's-eye-view planning technique prevents geographic target misses and better excludes healthy tissues from the treatment portal. Compared with scores for the beam's-eye-view planning technique, scores for

Image-guided radiotherapy in near real time with intensity-modulated radiotherapy megavoltage treatment beam imaging.

Science.gov (United States)

Mao, Weihua; Hsu, Annie; Riaz, Nadeem; Lee, Louis; Wiersma, Rodney; Luxton, Gary; King, Christopher; Xing, Lei; Solberg, Timothy

2009-10-01

To utilize image-guided radiotherapy (IGRT) in near real time by obtaining and evaluating the online positions of implanted fiducials from continuous electronic portal imaging device (EPID) imaging of prostate intensity-modulated radiotherapy (IMRT) delivery. Upon initial setup using two orthogonal images, the three-dimensional (3D) positions of all implanted fiducial markers are obtained, and their expected two-dimensional (2D) locations in the beam's-eye-view (BEV) projection are calculated for each treatment field. During IMRT beam delivery, EPID images of the megavoltage treatment beam are acquired in cine mode and subsequently analyzed to locate 2D locations of fiducials in the BEV. Simultaneously, 3D positions are estimated according to the current EPID image, information from the setup portal images, and images acquired at other gantry angles (the completed treatment fields). The measured 2D and 3D positions of each fiducial are compared with their expected 2D and 3D setup positions, respectively. Any displacements larger than a predefined tolerance may cause the treatment system to suspend the beam delivery and direct the therapists to reposition the patient. Phantom studies indicate that the accuracy of 2D BEV and 3D tracking are better than 1 mm and 1.4 mm, respectively. A total of 7330 images from prostate treatments were acquired and analyzed, showing a maximum 2D displacement of 6.7 mm and a maximum 3D displacement of 6.9 mm over 34 fractions. This EPID-based, real-time IGRT method can be implemented on any external beam machine with portal imaging capabilities without purchasing any additional equipment, and there is no extra dose delivered to the patient.

Health-Related Quality of Life in Patients With Locally Advanced Prostate Cancer After 76 Gy Intensity-Modulated Radiotherapy vs. 70 Gy Conformal Radiotherapy in a Prospective and Longitudinal Study

International Nuclear Information System (INIS)

Lips, Irene; Dehnad, Human; Kruger, Arto Boeken; Moorselaar, Jeroen van; Heide, Uulke van; Battermann, Jan; Vulpen, Marco van

2007-01-01

Purpose: To compare quality of life (QoL) after 70 Gy conformal radiotherapy with QoL after 76 Gy intensity-modulated radiotherapy (IMRT) in patients with locally advanced prostate carcinoma. Methods and Materials: Seventy-eight patients with locally advanced prostate cancer were treated with 70 Gy three-field conformal radiotherapy, and 92 patients received 76 Gy IMRT with fiducial markers for position verification. Quality of life was measured by RAND-36, the European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30(+3)), and the prostate-specific EORTC QLQ-PR25, before radiotherapy (baseline) and 1 month and 6 months after treatment. Quality of life changes in time (baseline vs. 1 month and baseline vs. 6 months) of ≥10 points were considered clinically relevant. Results: Differences between the treatment groups for QoL changes over time occurred in several QoL domains. The 76-Gy group revealed no significant deterioration in QoL compared with the 70-Gy group. The IMRT 76-Gy group even demonstrated a significantly better change in QoL from baseline to 1 month in several domains. The conformal 70-Gy group revealed temporary deterioration in pain, role functioning, and urinary symptoms; for the IMRT 76-Gy group a better QoL in terms of change in health existed after 1 month, which persisted after 6 months. For both treatment groups temporary deterioration in physical role restriction occurred after 1 month, and an improvement in emotional role restriction occurred after 6 months. Sexual activity was reduced after treatment for both groups and remained decreased after 6 months. Conclusions: Intensity-modulated radiotherapy and accurate position verification seem to provide a possibility to increase the radiation dose for prostate cancer without deterioration in QoL

Normal liver tissue sparing by intensity-modulated proton stereotactic body radiotherapy for solitary liver tumours

International Nuclear Information System (INIS)

Petersen, Joergen B. B.; Hansen, Anders T.; Lassen, Yasmin; Grau, Cai; Hoeyer, Morten; Muren, Ludvig P.

2011-01-01

Background. Stereotactic body radiotherapy (SBRT) is often the preferred treatment for the advanced liver tumours which owing to tumour distribution, size and multi-focality are out of range of surgical resection or radiofrequency ablation. However, only a minority of patients with liver tumours may be candidates for conventional SBRT because of the limited radiation tolerance of normal liver, intestine and other normal tissues. Due to the favourable depth-dose characteristics of protons, intensity-modulated proton therapy (IMPT) may be a superior alternative to photon-based SBRT. The purpose of this treatment planning study was therefore to investigate the potential sparing of normal liver by IMPT compared to photon-based intensity-modulated radiotherapy (IMRT) for solitary liver tumours. Material and methods. Ten patients with solitary liver metastasis treated at our institution with multi-field SBRT were retrospectively re-planned with IMRT and proton pencil beam scanning techniques. For the proton plans, two to three coplanar fields were used in contrast to five to six coplanar and non-coplanar photon fields. The same planning objectives were used for both techniques. A risk adapted dose prescription to the PTV surface of 12.5-16.75 Gy x 3 was used. Results. The spared liver volume for IMPT was higher compared to IMRT in all 10 patients. At the highest prescription dose level, the median liver volume receiving less than 15 Gy was 1411 cm 3 for IMPT and 955 cm 3 for IMRT (p D 15 Gy > 700 cm 3 constraint. For the D mean = 15 Gy constraint, nine of 10 cases could be treated at the highest dose level using IMPT whereas with IMRT, only two cases met this constraint at the highest dose level and six at the lowest dose level. Conclusion. A considerable sparing of normal liver tissue can be obtained using proton-based SBRT for solitary liver tumours

Outcomes and xerostomia after postoperative radiotherapy for oral and oropharyngeal carcinoma.

Science.gov (United States)

Wang, Zhong-He; Yan, Chao; Zhang, Zhi-Yuan; Zhang, Chen-Ping; Hu, Hai-Sheng; Tu, Wen-Yong; Kirwan, Jessica; Mendenhall, William M

2014-10-01

We compared outcomes and xerostomia grade after postoperative intensity-modulated radiation therapy (IMRT) and conventional radiotherapy (RT) in patients with oral and oropharyngeal carcinoma. Eighty-eight patients with oral cavity (n = 77) and oropharyngeal (n = 11) carcinoma underwent postoperative IMRT (n = 44) or conventional RT (n = 44). Outcomes, failure patterns, volume, doses, salivary gland V30, and xerostomia grade were evaluated. The median follow-up was 53 months (range, 48-58 months). The median interval from surgery to RT was 4 weeks (range, 3-6 weeks). Twenty-one patients (7 and 14 for the IMRT and conventional RT groups, respectively) experienced local-regional failure. For the IMRT group, all 7 local-regional failures occurred in the high-dose target volumes. For the conventional RT group, there were 12 in-field failures, 1 at the margin, and 1 out-of-field. Nine patients experienced distant failure (5 and 4 for the IMRT and conventional RT groups, respectively). The 4-year local-regional control, disease-free survival (DFS), overall survival (OS), and distant-metastasis rates for the IMRT and conventional RT groups were 84.1% versus 68.2% (p = .055), 68.2% versus 52.3% (p = .091), 70.5% versus 56.8% (p = .124), and 11.4% versus 9.1% (p = .927), respectively. Xerostomia grade after RT was lower for IMRT compared to conventional RT (p xerostomia grade when compared to conventional RT. The predominant failure pattern was local. No differences were found in survival outcomes between both groups. There was a marginal difference in local-regional control. © 2014 Wiley Periodicals, Inc.

Independent monitor unit calculation for intensity modulated radiotherapy using the MIMiC multileaf collimator

International Nuclear Information System (INIS)

Chen Zhe; Xing Lei; Nath, Ravinder

2002-01-01

A self-consistent monitor unit (MU) and isocenter point-dose calculation method has been developed that provides an independent verification of the MU for intensity modulated radiotherapy (IMRT) using the MIMiC (Nomos Corporation) multileaf collimator. The method takes into account two unique features of IMRT using the MIMiC: namely the gantry-dynamic arc delivery of intensity modulated photon beams and the slice-by-slice dose delivery for large tumor volumes. The method converts the nonuniform beam intensity planned at discrete gantry angles of 5 deg. or 10 deg. into conventional nonmodulated beam intensity apertures of elemental arc segments of 1 deg. This approach more closely simulates the actual gantry-dynamic arc delivery by MIMiC. Because each elemental arc segment is of uniform intensity, the MU calculation for an IMRT arc is made equivalent to a conventional arc with gantry-angle dependent beam apertures. The dose to the isocenter from each 1 deg. elemental arc segment is calculated by using the Clarkson scatter summation technique based on measured tissue-maximum-ratio and output factors, independent of the dose calculation model used in the IMRT planning system. For treatments requiring multiple treatment slices, the MU for the arc at each treatment slice takes into account the MU, leakage and scatter doses from other slices. This is achieved by solving a set of coupled linear equations for the MUs of all involved treatment slices. All input dosimetry data for the independent MU/isocenter point-dose calculation are measured directly. Comparison of the MU and isocenter point dose calculated by the independent program to those calculated by the Corvus planning system and to direct measurements has shown good agreement with relative difference less than ±3%. The program can be used as an independent initial MU verification for IMRT plans using the MIMiC multileaf collimators

SU-E-T-449: Hippocampal Sparing Radiotherapy Using Intensity Modulated Radiotherapy and Volumetric Modulated Arc Therapy

Energy Technology Data Exchange (ETDEWEB)

Moon, S [Korea University, Seoul (Korea, Republic of); Kyung Hee University Hospital at Gangdong, Gangdong-gu (Korea, Republic of); Kim, D; Chung, W [Kyung Hee University Hospital at Gangdong, Gangdong-gu (Korea, Republic of); Yoon, M [Korea University, Seoul (Korea, Republic of)

2015-06-15

Purpose: The hippocampus sparing during the cranial irradiation has become interesting because it may mitigate radiation-induced neurocognitive toxicity. Herein we report our preliminary study for sparing the hippocampus with and without tilling condition for patient with brain metastases. Methods: Ten patients previously treated with whole brain were reviewed. Five patients tilted the head to around 30 degrees and others were treated without tilting. Treatment plans of linear accelerator (Linac)-based volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) were generated for prescription dose of 30 Gy in 15 fractions. Hippocampal avoidance regions were created with 5-mm volumetric expansion around the hippocampus. Whole brain, hippocampus and hippocampal avoidance volume were 1372cm3, 6cm3 and 30cm3 and hippocampal avoidance volume was 2.2% of the whole brain planned target volume in average. Organs at risk (OARs) are hippocampus, eyes, lens, and cochleae. Coverage index (CVI), conformity index (CI), homogeneity index (HI) and mean dose to OARs were used to compare dose characteristic of tilted and non-tilted cases. Results: In IMRT, when CI, CVI and HI of whole brain were 0.88, 0.09 and 0.98 in both tilted and non-tilted cases, absorbed dose of hippocampal avoidance volume in tilted cases were 10% lower than non-tilted cases. Doses in other OARs such as eyes, lens, and cochleae were also decreased about 20% when tilting the head. When CI, HI and CVI in VMAT were 0.9, 0.08 and 0.99, the dose-decreased ratio of OARs in both with and without tilting cases were almost the same with IMRT. But absolute dose of hippocampal avoidance volume in VMAT was 30% lower than IMRT. Conclusion: This study confirms that dose to hippocampus decreases if patients tilt the head. When treating the whole brain with head tilted, patients can acquire the same successful treatment Result and also preserve their valuable memory.

Intensity-modulated radiotherapy for pituitary adenomas: The preliminary report of Cleveland Clinic experience

International Nuclear Information System (INIS)

Mackley, Heath B.; Reddy, Chandana A. M.S.; Lee, S.-Y.; Harnisch, Gayle A.; Mayberg, Marc R.; Hamrahian, Amir H.; Suh, John H.

2007-01-01

Purpose: Intensity-modulated radiotherapy (IMRT) is being increasingly used for the treatment of pituitary adenomas. However, there have been few published data on the short- and long-term outcomes of this treatment. This is the initial report of Cleveland Clinic's experience. Methods and Materials: Between February 1998 and December 2003, 34 patients with pituitary adenomas were treated with IMRT. A retrospective chart review was conducted for data analysis. Results: With a median follow-up of 42.5 months, the treatment has proven to be well tolerated, with performance status remaining stable in 90% of patients. Radiographic local control was 89%, and among patients with secretory tumors, 100% had a biochemical response. Only 1 patient required salvage surgery for progressive disease, giving a clinical progression free survival of 97%. The only patient who received more than 46 Gy experienced optic neuropathy 8 months after radiation. Smaller tumor volume significantly correlated with subjective improvements in nonvisual neurologic complaints (p = 0.03), and larger tumor volume significantly correlated with subjective worsening of visual symptoms (p = 0.05). New hormonal supplementation was required for 40% of patients. Younger patients were significantly more likely to require hormonal supplementation (p 0.03). Conclusions: Intensity-modulated radiation therapy is a safe and effective treatment for pituitary adenomas over the short term. Longer follow-up is necessary to determine if IMRT confers any advantage with respect to either tumor control or toxicity over conventional radiation modalities

Retrospective study of 48 cases of post-operative radiotherapy for head and neck cancer

International Nuclear Information System (INIS)

Mnejja, W.; Yahiaoui, S.; Siala, W.; Daoud, J.; Ghorbel, A.; Frikha, M.

2011-01-01

The authors report a study which aimed at assessing therapeutic results after post-operative radiotherapy of 48 patients suffering from head and neck cancers. The analysis is made in terms of cancer control, survival without recurrence and global survival. The post-operative radiotherapy improves the disease control rate. Ganglionary attack and capsular failure are survival prognosis factors. The concomitant association of chemo-therapy and radiotherapy should improve therapeutic results. Short communication

A Monte Carlo dosimetric quality assurance system for dynamic intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Takegawa, Hideki; Yamamoto, Tokihiro; Miyabe, Yuki; Teshima, Teruki; Kunugi, Tomoaki; Yano, Shinsuke; Mizowaki, Takashi; Nagata, Yasushi; Hiraoka, Masahiro

2005-01-01

We are developing a Monte Carlo (MC) dose calculation system, which can resolve dosimetric issues derived from multileaf collimator (MLC) design for routine dosimetric quality assurance (QA) of intensity-modulated radiotherapy (IMRT). The treatment head of the medical linear accelerator equipped with MLC was modeled using the EGS4 MC code. A graphical user interface (GUI) application was developed to implement MC dose computation in the CT-based patient model and compare the MC calculated results with those of a commercial radiotherapy treatment planning (RTP) system, Varian Eclipse. To reduce computation time, the EGS4 MC code has been parallelized on massive parallel processing (MPP) system using the message passing interface (MPI). The MC treatment head model and MLC model were validated by the measurement data sets of percentage depth dose (PDD) and off-center ratio (OCR) in the water phantom and the film measurements for the static and dynamic test patterns, respectively. In the treatment head model, the MC calculated results agreed with those of measurements for both of PDD and OCR. The MC could reproduce all of the MLC dosimetric effects. A quantitative comparison between the results of MC and Eclipse was successfully performed with the GUI application. Parallel speed-up became almost linear. An MC dosimetric QA system for dynamic IMRT has been developed, however there were large dose discrepancies between the MC and the measurement in the MLC model simulation, which are now being investigated. (author)

Is “pelvic radiation disease” always the cause of bowel symptoms following prostate cancer intensity-modulated radiotherapy?

International Nuclear Information System (INIS)

Min, Myo; Chua, Benjamin; Guttner, Yvonne; Abraham, Ned; Aherne, Noel J.; Hoffmann, Matthew; McKay, Michael J.; Shakespeare, Thomas P.

2014-01-01

Background: Pelvic radiation disease (PRD) also widely known as “radiation proctopathy” is a well recognised late side-effect following conventional prostate radiotherapy. However, endoscopic evaluation and/or specialist referral for new or persistent post-prostate radiotherapy bowel symptoms is not routine and serious diagnoses may potentially be missed. Here we report a policy of endoscopic evaluation of bowel symptoms persisting >90 days post radiotherapy for prostate cancer. Methods and materials: A consecutive series of 102 patients who had radical prostate intensity-modulated radiotherapy (IMRT)/image-guided radiotherapy (IGRT) and who had new or ongoing bowel symptoms or positive faecal occult blood tests (FOBT) on follow up visits more than three months after treatment, were referred for endoscopic examination. All but one (99%) had full colonoscopic investigation. Results: Endoscopic findings included gastric/colonic/rectal polyps (56%), diverticular disease (49%), haemorrhoids (38%), radiation proctopathy (29%), gastritis/oesophagitis (8%) and rarer diagnoses, including bowel cancer which was found in 3%. Only four patients (4%) had radiation proctopathy without associated pathology and 65 patients (63%) had more than one diagnosis. If flexible sigmoidoscopy alone were used, 36.6% of patients and 46.6% patients with polyp(s) would have had their diagnoses missed. Conclusions: Our study has shown that bowel symptoms following prostate IMRT/IGRT are due to numerous diagnoses other than PRD, including malignancy. Routine referral pathways should be developed for endoscopic evaluation/specialist review for patients with new or persistent bowel symptoms (or positive FOBT) following prostate radiotherapy. This recommendation should be considered for incorporation into national guidelines

Postoperative radiotherapy for intracranial meningioma

International Nuclear Information System (INIS)

Chun, Ha Chung; Lee, Myung Za

2001-01-01

To evaluate the effectiveness and tolerance of postoperative external radiotherapy for patients with intracranial meningiomas. The records of thirty three patients with intracranial meningiomas who were treated with postoperative external irradiation at our institution between Feb, 1988 and Nov, 1999 were retrospectively analyzed. Median age of patients at diagnosis was 53 years with range of 17 to 68 years. Sites of involvement were parasagital, cerebral convexity, sphenoid ridge, parasellar and tentorium cerebella. Of 33 evaluated patients, 15 transitional, 10 meningotheliomatous, 4 hemangiopericytic, 3 atypical and 1 malignant meningioma were identified. Four patients underwent biopsy alone and remaining 29 patients underwent total tumor resection. A dose of 50 to 60 Gy was delivered in 28-35 daily fractions over a period of 5 to 7 weeks. Follow-up period ranged from 12 months to 8 years. The actuarial survival rates at 5 and 7 years for entire group of patients were 78% and 67%, respectively. The corresponding disease free survival rates were 73% and 61 %, respectively. The overall local control rate at 5 years was 83%. One out of 25 patients in benign group developed local failure, while 4 out of 8 patients in malignant group did local failure (p <0.05), Of 4 patients who underwent biopsy alone, 2 developed local failure. There was no significant difference in 5 year actuarial survival between patients who underwent total tumor resection and those who did biopsy alone. Patients whose age is under 60 showed slightly better survival than those whose age is 60 or older, although this was not statistically significant. There was no documented late complications in any patients. Based on our study, we might conclude that postoperative external beam radiotherapy tends to improve survival of patients with intracranial meningiomas comparing with surgery alone

Patterns of Failure and Toxicity after Intensity-Modulated Radiotherapy for Head and Neck Cancer

International Nuclear Information System (INIS)

Schoenfeld, Gordon O.; Amdur, Robert J.; Morris, Christopher G.; Li, Jonathan G.; Hinerman, Russell W.; Mendenhall, William M.

2008-01-01

Purpose: To determine the outcome of patients treated with intensity-modulated radiotherapy (IMRT) for head and neck cancer. Methods and Materials: We reviewed the charts of 100 consecutive patients treated with IMRT for squamous cell carcinoma of the oropharynx (64%), nasopharynx (16%), hypopharynx (14%), and larynx (6%). Most patients were treated with a concomitant boost schedule to 72 Gy. Of the 100 patients, 54 (54%) received adjuvant chemotherapy, mostly concurrent cisplatin. The dosimetry plans for patients with either locoregional failure or Grade 4-5 complications were reviewed and fused over the computed tomography images corresponding with the location of the event. Marginal failures were defined as those that occurred at a region of high-dose falloff, where conventional fields would have provided better coverage. Results: The median follow-up of living patients was 3.1 years (range, 1-5.2 years). The 3-year rate of local control, locoregional control, freedom from relapse, cause-specific survival, and overall survival for all patients was 89%, 87%, 72%, 78%, and 71%, respectively. The 3-year rate of freedom from relapse, cause-specific survival, and overall survival for the 64 oropharynx patients was 86%, 92%, and 84%, respectively. Of the 10 local failures, 2 occurred at the margin of the high-dose planning target volume. Both regional failures occurred within the planning target volume. No locoregional failures occurred outside the planning target volume. Of the 100 patients, 8 and 5 had Grade 4 and 5 complications from treatment, respectively. All patients with Grade 5 complications had received adjuvant chemotherapy. No attempt was made to discriminate between the complications from IMRT and other aspects of the patients' treatment. Conclusion: Intensity-modulated radiotherapy did not compromise the outcome compared with what we have achieved with conventional techniques. The 2 cases of recurrence in the high-dose gradient region highlight the

Hippocampal-Sparing Whole-Brain Radiotherapy: A 'How-To' Technique Using Helical Tomotherapy and Linear Accelerator-Based Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Gondi, Vinai; Tolakanahalli, Ranjini; Mehta, Minesh P.; Tewatia, Dinesh; Rowley, Howard; Kuo, John S.; Khuntia, Deepak; Tome, Wolfgang A.

2010-01-01

Purpose: Sparing the hippocampus during cranial irradiation poses important technical challenges with respect to contouring and treatment planning. Herein we report our preliminary experience with whole-brain radiotherapy using hippocampal sparing for patients with brain metastases. Methods and Materials: Five anonymous patients previously treated with whole-brain radiotherapy with hippocampal sparing were reviewed. The hippocampus was contoured, and hippocampal avoidance regions were created using a 5-mm volumetric expansion around the hippocampus. Helical tomotherapy and linear accelerator (LINAC)-based intensity-modulated radiotherapy (IMRT) treatment plans were generated for a prescription dose of 30 Gy in 10 fractions. Results: On average, the hippocampal avoidance volume was 3.3 cm 3 , occupying 2.1% of the whole-brain planned target volume. Helical tomotherapy spared the hippocampus, with a median dose of 5.5 Gy and maximum dose of 12.8 Gy. LINAC-based IMRT spared the hippocampus, with a median dose of 7.8 Gy and maximum dose of 15.3 Gy. On a per-fraction basis, mean dose to the hippocampus (normalized to 2-Gy fractions) was reduced by 87% to 0.49 Gy 2 using helical tomotherapy and by 81% to 0.73 Gy 2 using LINAC-based IMRT. Target coverage and homogeneity was acceptable with both IMRT modalities, with differences largely attributed to more rapid dose fall-off with helical tomotherapy. Conclusion: Modern IMRT techniques allow for sparing of the hippocampus with acceptable target coverage and homogeneity. Based on compelling preclinical evidence, a Phase II cooperative group trial has been developed to test the postulated neurocognitive benefit.

The development of intensity modulated radiotherapy (IMRT) for prostate cancer at Austin and Repatriation Medical Centre (ARMC)

International Nuclear Information System (INIS)

Joon, D.L.; Mantle, C.; Viotto, A.; Rolfo, A.; Rykers, K.; Fernando, W.; Grace, M.; Liu, G.; Quong, G.; Feigen, M.; Wada, M.; Joon, M.L.; Fogarty, G.; Chao, M.W.; Khoo, V.

2003-01-01

To describe the protocol development of the IMRT program for prostate cancer at the ARMC. A series of protocols were defined and developed to facilitate the delivery of intensity modulated radiotherapy for prostate cancer. These included the following: 1. Physical Simulation including bowel and bladder preparation and immobilization 2. Image Acquisition including CT and MRI simulation scans with image co-registration 3. Contouring Definitions including target and organ at risk volumes as well as IMRT optimization and evaluation volumes 4. Radiotherapy Planning including constraint definition, inverse planning and CMS Focus specific parameters 5. DICOM RT interface including data transfer between CMS Focus and the Elekta Linac Desktop record and verify system 6. Verification including action limits and pre-treatment online EPID verification 7. Radiotherapy Delivery being that of step and shoot 8. Quality Assurance including physics testing and documentation The protocol development and testing has lead to the precise clinical delivery of IMRT for prostate cancer at ARMC that exceeds most of the parameters that were previously measured with our conventional and 3D conformal radiotherapy. Further development is now underway to allow it to be implemented as the routine treatment of prostate cancer at ARMC. The clinical implementation of IMRT for prostate cancer involves a collaborative team approach including radiation oncologists, radiation therapists, and radiation physics. This is necessary to develop the appropriate protocols and quality assurance for precision radiotherapy that is required for IMRT

Clinical Outcome in Posthysterectomy Cervical Cancer Patients Treated With Concurrent Cisplatin and Intensity-Modulated Pelvic Radiotherapy: Comparison With Conventional Radiotherapy

International Nuclear Information System (INIS)

Chen, M.-F.; Tseng, C.-J.; Tseng, C.-C.; Kuo, Y.-C.; Yu, C.-Y.; Chen, W.-C.

2007-01-01

Purpose: To assess local control and acute and chronic toxicity with intensity-modulated radiation therapy (IMRT) as adjuvant treatment of cervical cancer. Methods and Materials: Between April 2002 and February 2006, 68 patients at high risk of cervical cancer after hysterectomy were treated with adjuvant pelvic radiotherapy and concurrent chemotherapy. Adjuvant chemotherapy consisted of cisplatin (50 mg/m 2 ) for six cycles every week. Thirty-three patients received adjuvant radiotherapy by IMRT. Before the IMRT series was initiated, 35 other patients underwent conventional four-field radiotherapy (Box-RT). The two groups did not differ significantly in respect of clinicopathologic and treatment factors. Results: IMRT provided compatible local tumor control compared with Box-RT. The actuarial 1-year locoregional control for patients in the IMRT and Box-RT groups was 93% and 94%, respectively. IMRT was well tolerated, with significant reduction in acute gastrointestinal (GI) and genitourinary (GU) toxicities compared with the Box-RT group (GI 36 vs. 80%, p = 0.00012; GU 30 vs. 60%, p = 0.022). Furthermore, the IMRT group had lower rates of chronic GI and GU toxicities than the Box-RT patients (GI 6 vs. 34%, p = 0.002; GU 9 vs. 23%, p = 0.231). Conclusion: Our results suggest that IMRT significantly improved the tolerance to adjuvant chemoradiotherapy with compatible locoregional control compared with conventional Box-RT. However, longer follow-up and more patients are needed to confirm the benefits of IMRT

Dose deviations caused by positional inaccuracy of multileaf collimator in intensity modulated radiotherapy

International Nuclear Information System (INIS)

Wang, H.C.; Chui, C.S.; Tsai, H.Y.; Chen, C.H.; Tsai, L.F.

2008-01-01

Introduction: Multileaf collimator (MLC) is currently a widely used system in the delivery of intensity modulated radiotherapy (IMRT). The accuracy of the multileaf position plays an important role in the final outcome of the radiation treatment. According to ICRU recommendation, a dose inaccuracy over than 5% of prescribed dose affects treatment results. In order to quantify the influence of leaf positional errors on dose distribution, we set different MLC positional inaccuracy from 0 to 6 mm for step-and-shoot IMRT in clinical cases. Two-dimensional dose distributions of radiotherapy plans with different leaf displacements generated with a commercial treatment planning system. And verification films were used to measure two-dimensional dose distributions. Then a computerized dose comparison system will be introduced to analyze the dose deviations. Materials/methods: We assumed MLC positional inaccuracy from 0 to 6 mm for step-and-shoot IMRT in clinical cases by simulating the different leaf displacements with a commercial treatment planning system. Then we transferred the treatment plans with different leaf offset that may be happened in clinical situation to linear accelerator. Verification films (Kodat EDR2) were well positioned within solid water phantoms to be irradiated by the simulated plans. The films were scanned to display two-dimensional dose distributions. Finally, we compared with the dose distributions with MLC positional inaccuracy by a two-dimensional dose comparison software to analyze the deviations in Gamma indexes and normalized agreement test (NAT) values. Results: In general, the data show that larger leaf positional error induces larger dose error. More fields used for treatment generate lesser errors. Besides, leaf position relative to a field influences the degree of dose error. A leaf lying close to the border of a field leads to a more significant dose deviation than a leaf in the center. Algorithms for intensity modulation also affect

Quantitative comparison of volumetric modulated arc therapy and intensity modulated radiotherapy plan quality in sino-nasal cancer

International Nuclear Information System (INIS)

Sankaralingam, Marimuthu; Glegg, Martin; Smith, Suzanne; James, Allan; Rizwanullah, Mohammed

2012-01-01

The aim of this study was to compare various dosimetric parameters of dynamic mlc intensity modulated radiotherapy (IMRT) plans with volumetric modulated arc therapy (VMAT) plans for sino-nasal cancers, which are rare and complex tumors to treat with radiotherapy. IMRT using five fields, coplanar in the sagittal plane and VMAT employing two coplanar arc plans were created for five patients. The plans were assessed by comparing Conformity Index and Sigma Index (dose homogeneity) in the Planning Target Volume (PTV) and through comparison of dose-volume characteristics to the following organs at risk (OARs): Spinal cord, brainstem, eye, ipsilateral and contralateral optic nerve and the volume of brain receiving 10% of the prescribed dose (V 10% ). The total monitor units required to deliver the plan were also compared. Conformity Index was found to be superior in VMAT plans for three patients and in IMRT plans for two patients. Dose homogeneity within the PTV was better with VMAT plans for all five cases. The mean difference in Sigma Index was 0.68%. There was no significant difference in dose between IMRT and VMAT plans for any of the OARs assessed in these patients. The monitor units were significantly reduced in the VMAT plan in comparison to the IMRT plan for four out of five patients, with mean reduction of 66%. It was found in this study that for the treatment of sino-nasal cancer, VMAT produced minimal, and statistically insignificant improvement in dose homogeneity within the PTV when compared with IMRT. VMAT plans were delivered using significantly fewer monitor units. We conclude in this study that VMAT does not offer significant improvement of treatment for sino-nasal cancer over the existing IMRT techniques, but the findings may change with a larger sample of patients in this rare condition. (author)

Comparison between intensity modulated radiotherapy (IMRT) and 3D tangential beams technique used in patients with early-stage breast cancer who received breast-conserving therapy

International Nuclear Information System (INIS)

Sas-Korczynska, B.; Kokoszka, A.; Korzeniowski, S.; Sladowska, A.; Rozwadowska-Bogusz, B.; Lesiak, J.; Dyczek, S.

2010-01-01

Background: The most often found complications in patients with breast cancer who received radiotherapy are cardiac and pulmonary function disorders and development of second malignancies. Aim: To compare the intensity modulated radiotherapy with the 3D tangential beams technique in respect of dose distribution in target volume and critical organs they generate in patients with early-stage breast cancer who received breast-conserving therapy. Materials and methods: A dosimetric analysis was performed to assess the three radiotherapy techniques used in each of 10 consecutive patients with early-stage breast cancer treated with breast-conserving therapy. Radiotherapy was planned with the use of all the three techniques: 3D tangential beams with electron boost, IMRT with electron boost, and intensity modulated radiotherapy with simultaneous integrated boost. Results: The use of the IMRT techniques enables more homogenous dose distribution in target volume. The range of mean and median dose to the heart and lung was lower with the IMRT techniques in comparison to the 3D tangential beams technique. The range of mean dose to the heart amounted to 0.3 - 3.5 Gy for the IMRT techniques and 0.4 - 4.3 for the tangential beams technique. The median dose to the lung on the irradiated side amounted to 4.9 - 5 Gy for the IMRT techniques and 5.6 Gy for the 3D tangential beams technique. Conclusion: The application of the IMRT techniques in radiotherapy patients with early-stage breast cancer allows to obtain more homogenous dose distribution in target volume, while permitting to reduce the dose to critical organs. (authors)

Postoperative radiotherapy for parotid gland malignancy

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Eom, Keun Yong; Wu, Hong Gyun; Kim, Jae Sung; Park, Charn Il; Kim, Kwang Hyun; Lee, Chae Seo [Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, In Ah [Bundang Seoul National University Hospital, Seongnam (Korea, Republic of)

2005-09-15

The aim of this study was to evaluate the clinical results of postoperative radiotherapy for parotid gland malignancy, and determine prognostic factors for locoregional control and survival. Between 1980 and 2002, 130 patients with parotid malignancy were registered in the database of the Department of Radiation Oncology, Seoul National University Hospital. The subjects of this analysis were the 72 of these 130 patients who underwent postoperative irradiation. There were 42 males and 30 females, with a median age of 46.5 years. The most common histological type was a mucoepidermoid carcinoma. There were 6, 23, 23 and 20 patients in Stages I, II, III and IV, respectively. The median dose to the tumor bed was 60 Gy, with a median fraction size of 1.8 Gy. The overall 5 and 10 year survival rates were 85 and 76%, respectively. The five-year locoregional control rate was 85%, which reached a plateau phase after 6 years. Sex and histological type were found to be statistically significant for overall survival from a multivariate analysis. No other factors, including age, facial nerve palsy and stage, were related to overall survival. For locoregional control, nodal involvement and positive resection margin were associated with poor local control. Histological type, tumor size, perineural invasion and type of surgery were not significant for locoregional control. A high survival rate of parotid gland malignancies, with surgery and postoperative radiotherapy, was confirmed. Sex and histological type were significant prognostic factors for overall survival. Nodal involvement and a positive resection margin were associated with poor locoregional control.

Image-Guided Radiotherapy in Near Real Time With Intensity-Modulated Radiotherapy Megavoltage Treatment Beam Imaging

International Nuclear Information System (INIS)

Mao Weihua; Hsu, Annie; Riaz, Nadeem; Lee, Louis; Wiersma, Rodney; Luxton, Gary; King, Christopher; Xing Lei; Solberg, Timothy

2009-01-01

Purpose: To utilize image-guided radiotherapy (IGRT) in near real time by obtaining and evaluating the online positions of implanted fiducials from continuous electronic portal imaging device (EPID) imaging of prostate intensity-modulated radiotherapy (IMRT) delivery. Methods and Materials: Upon initial setup using two orthogonal images, the three-dimensional (3D) positions of all implanted fiducial markers are obtained, and their expected two-dimensional (2D) locations in the beam's-eye-view (BEV) projection are calculated for each treatment field. During IMRT beam delivery, EPID images of the megavoltage treatment beam are acquired in cine mode and subsequently analyzed to locate 2D locations of fiducials in the BEV. Simultaneously, 3D positions are estimated according to the current EPID image, information from the setup portal images, and images acquired at other gantry angles (the completed treatment fields). The measured 2D and 3D positions of each fiducial are compared with their expected 2D and 3D setup positions, respectively. Any displacements larger than a predefined tolerance may cause the treatment system to suspend the beam delivery and direct the therapists to reposition the patient. Results: Phantom studies indicate that the accuracy of 2D BEV and 3D tracking are better than 1 mm and 1.4 mm, respectively. A total of 7330 images from prostate treatments were acquired and analyzed, showing a maximum 2D displacement of 6.7 mm and a maximum 3D displacement of 6.9 mm over 34 fractions. Conclusions: This EPID-based, real-time IGRT method can be implemented on any external beam machine with portal imaging capabilities without purchasing any additional equipment, and there is no extra dose delivered to the patient.

Intensity modulated radiotherapy for elderly bladder cancer patients

International Nuclear Information System (INIS)

Hsieh, Chen-Hsi; Wang, Li-Ying; Hsieh, Yen-Ping; Shueng, Pei-Wei; Chung, Shiu-Dong; Chan, Pei-Hui; Lai, Siu-Kai; Chang, Hsiao-Chun; Hsiao, Chi-Huang; Wu, Le-Jung; Chong, Ngot-Swan; Chen, Yu-Jen

2011-01-01

To review our experience and evaluate treatment planning using intensity-modulated radiotherapy (IMRT) and helical tomotherapy (HT) for the treatment of elderly patients with bladder cancer. From November 2006 through November 2009, we enrolled 19 elderly patients with histologically confirmed bladder cancer, 9 in the IMRT and 10 in the HT group. The patients received 64.8 Gy to the bladder with or without concurrent chemotherapy. Conventional 4-field 'box' pelvic radiation therapy (2DRT) plans were generated for comparison. The median patient age was 80 years old (range, 65-90 years old). The median survival was 21 months (5 to 26 months). The actuarial 2-year overall survival (OS) for the IMRT vs. the HT group was 26.3% vs .37.5%, respectively; the corresponding values for disease-free survival were 58.3% vs. 83.3%, respectively; for locoregional progression-free survival (LRPFS), the values were 87.5% vs. 83.3%, respectively; and for metastases-free survival, the values were 66.7% vs. 60.0%, respectively. The 2-year OS rates for T1, 2 vs. T3, 4 were 66.7% vs. 35.4%, respectively (p = 0.046). The 2-year OS rate was poor for those whose RT completion time greater than 8 weeks when compared with the RT completed within 8 wks (37.9% vs. 0%, p = 0.004). IMRT and HT provide good LRPFS with tolerable toxicity for elderly patients with invasive bladder cancer. IMRT and HT dosimetry and organ sparing capability were superior to that of 2DRT, and HT provides better sparing ability than IMRT. The T category and the RT completion time influence OS rate

Transitioning from conventional radiotherapy to intensity-modulated radiotherapy for localized prostate cancer. Changing focus from rectal bleeding to detailed quality of life analysis

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Yamazaki, Hideya; Nakamura, Satoaki; Nishimura, Takuya; Yoshida, Ken; Yoshioka, Yasuo; Koizumi, Masahiko; Ogawa, Kazuhiko

2014-01-01

With the advent of modern radiation techniques, we have been able to deliver a higher prescribed radiotherapy dose for localized prostate cancer without severe adverse reactions. We reviewed and analyzed the change of toxicity profiles of external beam radiation therapy (EBRT) from the literature. Late rectal bleeding is the main adverse effect, and an incidence of >20% of Grade ≥2 adverse events was reported for 2D conventional radiotherapy of up to 70 Gy. 3D conformal radiation therapy (3D-CRT) was found to reduce the incidence to ∼10%. Furthermore, intensity-modulated radiation therapy (IMRT) reduced it further to a few percentage points. However, simultaneously, urological toxicities were enhanced by dose escalation using highly precise external radiotherapy. We should pay more attention to detailed quality of life (QOL) analysis, not only with respect to rectal bleeding but also other specific symptoms (such as urinary incontinence and impotence), for two reasons: (1) because of the increasing number of patients aged >80 years, and (2) because of improved survival with elevated doses of radiotherapy and/or hormonal therapy; age is an important prognostic factor not only for prostate-specific antigen (PSA) control but also for adverse reactions. Those factors shift the main focus of treatment purpose from survival and avoidance of PSA failure to maintaining good QOL, particularly in older patients. In conclusion, the focus of toxicity analysis after radiotherapy for prostate cancer patients is changing from rectal bleeding to total elaborate quality of life assessment. (author)

Postoperative radiotherapy for stage II and III rectal cancer

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Qian Liting; Song Yongwen; Liu Xinfan; Yu Zihao; Qian Tunan; Li Yexiong

2003-01-01

Objective: To evaluate the impact of postoperative adjuvant radiotherapy, compared with surgery alone for rectal cancer. Methods: From January 1994 to October 1997, 192 patients with stage II or III rectal cancer were treated by radical resection and postoperative radiotherapy (Group S + R) and 51 patients with the same stage lesions underwent surgery alone (Group S). The median dose of radiation was 50(32-62) Gy. Kaplan-Meier method and Log-rank test were used for analysis. Results: The 5-year overall and disease-free survival rates were 60.3% and 58.3%, respectively. The overall 5-year survival rate was 59.4% in Group S + R and 64.7% in Group S, and the 5-year disease-free survival rates were 57.0% and 66.4%, respectively. There were no significant differences between either group (P=0.601 and P=0.424). The disease-free survival was not significantly prolonged in Group S + R as compared with that of Group S. The local recurrence rate was evidently reduced in Group S + R (15.8% v 26.8%, P=0.043). Conclusion: Local recurrence is a major cause of morbidity and mortality in rectal cancer. Postoperative radiotherapy, though reduces the incidence of local recurrence, does not improve the survival in the treatment of stage II and III diseases

Treatment Result of Postoperative Radiotherapy of Carcinoma of the Uterine Cervix

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Park, Charn Il; Kim, Il Han; Ha, Sung Whan; Lee, Hyo Pyo; Shin, Myon Woo; Kim, Jung Soo

1985-01-01

The early carcinoma of the uterine cervix may be treated by either radical surgery or radical radiotherapy according to the patient characteristics, and the survival is high with either treatment. But, because of the size of the lesion, metastasis to lymph nodes, and vascular space invasion by tumor have all been shown to influence recurrence and survival, postoperative radiotherapy may be considered as their histopathologic finding after radical surgery. However, there are still debates on the increasing survival rates with postoperative radiotherapy. Two hundreds and three patients with carcinoma of the uterine cervix who were treated with postoperative radiotherapy from February 1979 to September 1982 in the Department of Therapeutic Radiology, Seoul National University were analyzed and following results were obtained. 3-year actuarial survival rate and 3-year disease free survival rate were 83.4% and 73.4% respectively and 3-year actuarial survival rates by stages were 90.7% for I B, 69.6% for II A, and 85.2% for II b. The overall acute complication rate was 57.6%; tolerable cases was 50.2% and severe cases was 7.4%, Late complication rate was 7.9% and the major late complication were intestinal obstruction, aggravated urinary symptom, radiation cystitis in ORDER of frequency

Dosimetric and Radiobiologic Comparison of 3D Conformal Versus Intensity Modulated Planning Techniques for Prostate Bed Radiotherapy

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Koontz, Bridget F.; Das, Shiva; Temple, Kathy; Bynum, Sigrun; Catalano, Suzanne; Koontz, Jason I.; Montana, Gustavo S.; Oleson, James R.

2009-01-01

Adjuvant radiotherapy for locally advanced prostate cancer improves biochemical and clinical disease-free survival. While comparisons in intact prostate cancer show a benefit for intensity modulated radiation therapy (IMRT) over 3D conformal planning, this has not been studied for post-prostatectomy radiotherapy (RT). This study compares normal tissue and target dosimetry and radiobiological modeling of IMRT vs. 3D conformal planning in the postoperative setting. 3D conformal plans were designed for 15 patients who had been treated with IMRT planning for salvage post-prostatectomy RT. The same computed tomography (CT) and target/normal structure contours, as well as prescription dose, was used for both IMRT and 3D plans. Normal tissue complication probabilities (NTCPs) were calculated based on the dose given to the bladder and rectum by both plans. Dose-volume histogram and NTCP data were compared by paired t-test. Bladder and rectal sparing were improved with IMRT planning compared to 3D conformal planning. The volume of the bladder receiving at least 75% (V75) and 50% (V50) of the dose was significantly reduced by 28% and 17%, respectively (p = 0.002 and 0.037). Rectal dose was similarly reduced, V75 by 33% and V50 by 17% (p = 0.001 and 0.004). While there was no difference in the volume of rectum receiving at least 65 Gy (V65), IMRT planning significant reduced the volume receiving 40 Gy or more (V40, p = 0.009). Bladder V40 and V65 were not significantly different between planning modalities. Despite these dosimetric differences, there was no significant difference in the NTCP for either bladder or rectal injury. IMRT planning reduces the volume of bladder and rectum receiving high doses during post-prostatectomy RT. Because of relatively low doses given to the bladder and rectum, there was no statistically significant improvement in NTCP between the 3D conformal and IMRT plans.

Dosimetric and radiobiologic comparison of 3D conformal versus intensity modulated planning techniques for prostate bed radiotherapy.

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Koontz, Bridget F; Das, Shiva; Temple, Kathy; Bynum, Sigrun; Catalano, Suzanne; Koontz, Jason I; Montana, Gustavo S; Oleson, James R

2009-01-01

Adjuvant radiotherapy for locally advanced prostate cancer improves biochemical and clinical disease-free survival. While comparisons in intact prostate cancer show a benefit for intensity modulated radiation therapy (IMRT) over 3D conformal planning, this has not been studied for post-prostatectomy radiotherapy (RT). This study compares normal tissue and target dosimetry and radiobiological modeling of IMRT vs. 3D conformal planning in the postoperative setting. 3D conformal plans were designed for 15 patients who had been treated with IMRT planning for salvage post-prostatectomy RT. The same computed tomography (CT) and target/normal structure contours, as well as prescription dose, was used for both IMRT and 3D plans. Normal tissue complication probabilities (NTCPs) were calculated based on the dose given to the bladder and rectum by both plans. Dose-volume histogram and NTCP data were compared by paired t-test. Bladder and rectal sparing were improved with IMRT planning compared to 3D conformal planning. The volume of the bladder receiving at least 75% (V75) and 50% (V50) of the dose was significantly reduced by 28% and 17%, respectively (p = 0.002 and 0.037). Rectal dose was similarly reduced, V75 by 33% and V50 by 17% (p = 0.001 and 0.004). While there was no difference in the volume of rectum receiving at least 65 Gy (V65), IMRT planning significant reduced the volume receiving 40 Gy or more (V40, p = 0.009). Bladder V40 and V65 were not significantly different between planning modalities. Despite these dosimetric differences, there was no significant difference in the NTCP for either bladder or rectal injury. IMRT planning reduces the volume of bladder and rectum receiving high doses during post-prostatectomy RT. Because of relatively low doses given to the bladder and rectum, there was no statistically significant improvement in NTCP between the 3D conformal and IMRT plans.

Intensity-modulated radiotherapy for neoadjuvant treatment of gastric cancer

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Knab, Brian; Rash, Carla; Farrey, Karl; Jani, Ashesh B.

2006-01-01

Radiation therapy plays an integral role in the treatment of gastric cancer in the postsurgery setting, the inoperable/palliative setting, and, as in the case of the current report, in the setting of neoadjuvant therapy prior to surgery. Typically, anterior-posterior/posterior-anterior (AP/PA) or 3-field techniques are used. In this report, we explore the use of intensity-modulated radiotherapy (IMRT) treatment in a patient whose care was transferred to our institution after 3-field radiotherapy (RT) was given to a dose of 30 Gy at an outside institution. If the 3-field plan were continued to 50 Gy, the volume of irradiated liver receiving greater than 30 Gy would have been unacceptably high. To deliver the final 20 Gy, an opposed parallel AP/PA plan and an IMRT plan were compared to the initial 3-field technique for coverage of the target volume as well as dose to the kidneys, liver, small bowel, and spinal cord. Comparison of the 3 treatment techniques to deliver the final 20 Gy revealed reduced median and maximum dose to the whole kidney with the IMRT plan. For this 20-Gy boost, the volume of irradiated liver was lower for both the IMRT plan and the AP/PA plan vs. the 3-field plan. Comparing the IMRT boost plan to the AP/PA boost-dose range ( 10 Gy) in comparison to the AP/PA plan. The IMRT boost plan also irradiated a smaller volume of the small bowel compared to both the 3-field plan and the AP/PA plan, and also delivered lower dose to the spinal cord in comparison to the AP/PA plan. Comparison of the composite plans revealed reduced dose to the whole kidney using IMRT. The V20 for the whole kidney volume for the composite IMRT plan was 30% compared to approximately 60% for the composite AP/PA plan. Overall, the dose to the liver receiving greater than 30 Gy was lower for the composite IMRT plan and was well below acceptable limits. In conclusion, our study suggests a dosimetric benefit of IMRT over conventional planning, and suggests an important role for

Intensity-modulated radiotherapy with simultaneous modulated accelerated boost technique and chemotherapy in patients with nasopharyngeal carcinoma

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Fareed, Muhammad M; AlAmro, Abdullah S; Bayoumi, Yasser; Tunio, Mutahir A; Ismail, Abdul S; Akasha, Rashad; Mubasher, Mohamed; Al Asiri, Mushabbab

2013-01-01

To present our experience of intensity-modulated radiotherapy (IMRT) with simultaneous modulated accelerated radiotherapy (SMART) boost technique in patients with nasopharyngeal carcinoma (NPC). Sixty eight patients of NPC were treated between April 2006 and December 2011 including 45 males and 23 females with mean age of 46 (range 15–78). Stage distribution was; stage I 3, stage II 7, stage III 26 and stage IV 32. Among 45 (66.2%) evaluated patients for presence of Epstein-Barr virus (EBV), 40 (88.8%) were positive for EBV. Median radiation doses delivered to gross tumor volume (GTV) and positive neck nodes were 66–70 Gy, 63 Gy to clinical target volume (CTV) and 50.4 Gy to clinically negative neck. In addition 56 (82.4%) patients with bulky tumors (T4/N2+) received neoadjuvant chemotherapy 2–3 cycles (Cisplatin/Docetaxel or Cisplatin/Epirubicin or Cisplatin/5 Flourouracil). Concurrent chemotherapy with radiation was weekly Cisplatin 40 mg/m 2 (40 patients) or Cisplatin 100 mg/m 2 (28 patients). With a median follow up of 20 months (range 3–43), one patient developed local recurrence, two experienced regional recurrences and distant failure was seen in 3 patients. Estimated 3 year disease free survival (DFS) was 94%. Three year DFS for patients with EBV was 100% as compared to 60% without EBV (p = 0.0009). Three year DFS for patients with undifferentiated histology was 98% as compared to 82% with other histologies (p = 0.02). Acute grade 3 toxicity was seen as 21 (30.9%) having G-III mucositis and 6 (8.8%) with G-III skin reactions. Late toxicity was minimal and loss of taste was seen in 3 patients (7.5%) at time of analysis. IMRT with SMART in combination with chemotherapy is feasible and effective in terms of both the clinical response and safety profile. EBV, histopathology and nodal involvement were found important prognostic factors for locoregional recurrence

Effect of stereotactic body radiotherapy versus intensity-modulated radiotherapy in primary liver cancer patients with secondary malignant tumor of vertebra

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SUN Jing

2016-06-01

Full Text Available ObjectiveTo investigate the effect of stereotactic body radiotherapy (SBRT versus intensity-modulated radiotherapy (IMRT in primary liver cancer (PLC patients with secondary malignant tumor of vertebra. MethodsA total of 49 PLC patients with secondary metastatic tumor of vertebra, who were treated in our hospital from December 2011 to January 2014, were enrolled and divided into group A (20 patients treated with SBRT and group B (29 patients treated with IMRT. The prescribed dose was 35 Gy in 5 fractions in group A and 35 Gy in 10 fractions in group B. The time to pain relief, imaging findings, and survival analysis were used to evaluate pain-relieving effect, the condition of lesions, and survival time. The t-test was used to compare continuous data between groups, and the chi-square test was used to compare categorical data between groups. The K-M method was used to plot survival curves for both groups, and the log-rank test was used for survival difference analysis. ResultsThe proportion of patients who achieved complete or partial remission and stable disease shown by radiological examination after radiotherapy showed no significant difference between group A and group B (P=0.873. The pain relief rate also showed no significant difference between group A and group B (P=0.908. The time of pain relief showed a significant difference between group A and group B (t=-3.353, P＜0.01. The overall survival showed no significant difference between the two groups (P=0.346. ConclusionRadiotherapy has a definite therapeutic effect in PLC patients with secondary malignant tumor of vertebra. SBRT and IMRT have similar pain-relieving effects. However, with the same prescribed dose, SBRT has a short time to pain relief and does not lead to serious intolerable acute or late toxic and side effects in surrounding fast-response tissues.

Nasopharyngeal Carcinoma Treated with Precision-Oriented Radiation Therapy Techniques Including Intensity-Modulated Radiotherapy: Preliminary Results

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Wen-Shan Liu

2004-02-01

Full Text Available This paper reports preliminary results with intensity-modulated radiotherapy (IMRT in nasopharyngeal carcinoma (NPC. Between August 2000 and May 2001, we treated 19 patients with NPC using IMRT. Twelve patients had stage I-II disease and seven had stage III-IV disease. Six patients received 9.0-19.8 Gy three-dimensional conformal radiotherapy (3D-CRT before IMRT and 18 patients received a brachytherapy boost after IMRT. The mean follow-up time was 13.0 months. All patients with stage II-IV disease except one received two cycles of chemoradiotherapy with cisplatin and 5-fluorouracil (5-FU during radiotherapy, followed by two to four cycles of chemotherapy after radiotherapy. Tumor response was assessed using clinical examination and computerized tomography or magnetic resonance imaging. The mean doses administered to the gross tumor volume and clinical tumor volume were 70.9 Gy and 63.2 Gy, respectively. The mean doses administered to the right and left parotid glands were 38.1 Gy and 38.6 Gy, respectively. All 19 patients had a complete response of primary and lymph node disease. Grade III mucositis developed during chemoradiotherapy in 15 patients (79%. In addition, clinical grade I xerostomia was recorded in nine patients, grade II in nine, and grade III in one. This study demonstrated that 3D-CRT, IMRT, intracavitary brachytherapy, and chemotherapy are effective and safe methods to treat NPC. Although IMRT treatment spared parotid gland function, its efficacy may be significantly influenced by disease stage and location of the neck lymph nodes. More cases and a longer follow-up to assess survival and complications are planned.

Dosimetric planning study for the prevention of anal complications after post-operative whole pelvic radiotherapy in cervical cancer patients with hemorrhoids.

Science.gov (United States)

Baek, J G; Kim, E C; Kim, S K; Jang, H

2015-01-01

Radiation-induced anal toxicity can be induced by low radiation doses in patients with haemorrhoids. The object of this study was to determine the dosimetric benefits of different whole pelvic radiotherapy (WPRT) techniques in terms of dose delivered to the anal canal in post-operative patients with cervical cancer. The planning CT images of 10 patients with cervical cancer undergoing postoperative radiotherapy were used for comparison of three different plans. All patients had been treated using the conventional box technique WPRT (CV-WPRT), and we tried low-margin-modified WPRT (LM-WPRT), three-dimensional conformal techniques WPRT (CF-WPRT) and intensity-modulated WPRT (IM-WPRT) planning for dosimetric comparison of the anal canal, retrospectively. Mean anal canal doses of the IM-WPRT were significantly lower (p 99%, and the proportion that received ≥108% of the prescribed dose for IM-WPRT was <2%. Volumes of bladders and rectums that received ≥30 or ≥40 Gy were significantly lower for IM-WPRT than for three of the four-field WPRT plans (p = 0.000). IM-WPRT can significantly reduce radiation dose delivered to the anal canal and does not compromise PTV coverage. In patients with haemorrhoids, IM-WPRT may be of value for the prevention of anal complications. Although tolerance of the anal canal tends to be ignored in patients undergoing post-operative WPRT, patients with haemorrhoids may suffer complications at low radiation doses. The present study shows IM-WPRT can be meaningful in these patients.

Improved genetic algorithm in optimization of beam orientation in intensity modulated radiotherapy

International Nuclear Information System (INIS)

Ni Xinye; Yang Jianhua; Sun Suping; Yao Yi

2009-01-01

Objective: At present beam orientation selection in intensity-modulated radiotherapy (IMRT) is mainly based on empiric knowledge. This study is to evaluate the feasibility of automated beam angle selection. Methods: Genetic algorithm technique which based on beam eye view dose measurement (BEVD-GA) was tested on two clinical cases, including a spine column cancer and a lung cancer. Three plans were obtained under the following different beam configurations: five equiangular-spaced beams, five beams with GA-selected, and five beams with BEVD-GA-selected beams. Then the dose distribution was compared among the three plans. Results: The method, restricting the range of genetic algorithm followed by carrying through genetic operations, not only shortened the optimization time, but also improved the optimization effect. For spine column cancer and lung cancer, the best IMRT plans were obtained with BEVD-GA-selected beams, which used automated beam orientation selection. Conclusions: Comparing with the conventional manual beam orientation selection, beam orientation optimization which is feasible in IMRT planning may significantly improve the efficiency and result. (authors)

Late xerostomia after intensity-modulated conformational radiotherapy of upper aero-digestive tract cancers: study 2004-03 by the head and neck oncology and radiotherapy Group (Gortec)

International Nuclear Information System (INIS)

Toledano, I.; Lapeyre, M.; Graff, P.; Serre, C.; Bensadoun, R.J.; Bensadoun, R.J.; Ortholan, C.; Calais, G.; Alfonsi, M.; Giraud, P.; Racadot, S.

2010-01-01

The authors report a retrospective assessment of late xerostomia according to the RTOG (Radiation Therapy Oncology Group) classification of the European Organization for Research and Treatment of Cancer (EORTC) among patients treated by intensity-modulated conformational radiotherapy (IMRT) and suffering from upper aero-digestive tract carcinomas of different stages. Some of these patients have bee operated, and some have been treated by chemotherapy. It appears that the IMRT results in a reduction of late xerostomia, and even in an absence of salivary toxicity. Short communication

Prostate Bed Motion During Intensity-Modulated Radiotherapy Treatment

International Nuclear Information System (INIS)

Klayton, Tracy; Price, Robert; Buyyounouski, Mark K.; Sobczak, Mark; Greenberg, Richard; Li, Jinsheng; Keller, Lanea; Sopka, Dennis; Kutikov, Alexander; Horwitz, Eric M.

2012-01-01

Purpose: Conformal radiation therapy in the postprostatectomy setting requires accurate setup and localization of the prostatic fossa. In this series, we report prostate bed localization and motion characteristics, using data collected from implanted radiofrequency transponders. Methods and Materials: The Calypso four-dimensional localization system uses three implanted radiofrequency transponders for daily target localization and real-time tracking throughout a course of radiation therapy. We reviewed the localization and tracking reports for 20 patients who received ultrasonography-guided placement of Calypso transponders within the prostate bed prior to a course of intensity-modulated radiation therapy at Fox Chase Cancer Center. Results: At localization, prostate bed displacement relative to bony anatomy exceeded 5 mm in 9% of fractions in the anterior-posterior (A-P) direction and 21% of fractions in the superior-inferior (S-I) direction. The three-dimensional vector length from skin marks to Calypso alignment exceeded 1 cm in 24% of all 652 fractions with available setup data. During treatment, the target exceeded the 5-mm tracking limit for at least 30 sec in 11% of all fractions, generally in the A-P or S-I direction. In the A-P direction, target motion was twice as likely to move posteriorly, toward the rectum, than anteriorly. Fifteen percent of all treatments were interrupted for repositioning, and 70% of patients were repositioned at least once during their treatment course. Conclusion: Set-up errors and motion of the prostatic fossa during radiotherapy are nontrivial, leading to potential undertreatment of target and excess normal tissue toxicity if not taken into account during treatment planning. Localization and real-time tracking of the prostate bed via implanted Calypso transponders can be used to improve the accuracy of plan delivery.

SU-E-T-409: Intensity Modulated Robotic Radiotherapy

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Wang, B; Jin, L; Li, J; Chen, L; Ma, C; Fan, J; Zhang, C

2014-01-01

Purpose: As compared with the IRIS-based models, the MLC-based CyberKnife system allows more efficient treatment delivery due to its improved coverage of large lesions and intensity modulation. The treatment delivery efficiency is mainly determined by the number of selected nodes. This study aimed to demonstrate that relatively small sets of optimally selected nodes could produce high-quality plans. Methods: The full body path of the CyberKnife system consists of 110 nodes, from which we selected various sets for 4 prostate cancer cases using our in-house beamselection software. With the selected nodes we generated IMRT plans using our in-house beamlet-based inverse-planning optimization program. We also produced IMRT plans using the MultiPlan treatment planning system (version 5.0) for the same cases. Furthermore, the nodes selected by MultiPlan were used to produce plans with our own optimization software so that we could compare the quality of the selected sets of nodes. Results: Our beam-selection program selected one node-set for each case, with the number of nodes ranging from 23 to 34. The IMRT plans based on the selected nodes and our in-house optimization program showed adequate target coverage, with favorable critical structure sparing for the cases investigated. Compared with the plans using the nodes selected by MultiPlan, the plans generated with our selected beams provided superior rectum/bladder sparing for 75% of the cases. The plans produced by MultiPlan with various numbers of nodes also suggested that the plan quality was not compromised significantly when the number of nodes was reduced. Conclusion: Our preliminary results showed that with beamletbased planning optimization, one could produce high-quality plans with an optimal set of nodes for MLC-based robotic radiotherapy. Furthermore, our beam-selection strategy could help further improve critical structure sparing

Intensity modulated radiotherapy for elderly bladder cancer patients

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Chong Ngot-Swan

2011-06-01

Full Text Available Abstract Background To review our experience and evaluate treatment planning using intensity-modulated radiotherapy (IMRT and helical tomotherapy (HT for the treatment of elderly patients with bladder cancer. Methods From November 2006 through November 2009, we enrolled 19 elderly patients with histologically confirmed bladder cancer, 9 in the IMRT and 10 in the HT group. The patients received 64.8 Gy to the bladder with or without concurrent chemotherapy. Conventional 4-field "box" pelvic radiation therapy (2DRT plans were generated for comparison. Results The median patient age was 80 years old (range, 65-90 years old. The median survival was 21 months (5 to 26 months. The actuarial 2-year overall survival (OS for the IMRT vs. the HT group was 26.3% vs .37.5%, respectively; the corresponding values for disease-free survival were 58.3% vs. 83.3%, respectively; for locoregional progression-free survival (LRPFS, the values were 87.5% vs. 83.3%, respectively; and for metastases-free survival, the values were 66.7% vs. 60.0%, respectively. The 2-year OS rates for T1, 2 vs. T3, 4 were 66.7% vs. 35.4%, respectively (p = 0.046. The 2-year OS rate was poor for those whose RT completion time greater than 8 weeks when compared with the RT completed within 8 wks (37.9% vs. 0%, p = 0.004. Conclusion IMRT and HT provide good LRPFS with tolerable toxicity for elderly patients with invasive bladder cancer. IMRT and HT dosimetry and organ sparing capability were superior to that of 2DRT, and HT provides better sparing ability than IMRT. The T category and the RT completion time influence OS rate.

Occult carcinoma discovered after simple hysterectomy treated with postoperative radiotherapy

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Crane, Christopher H.; Schneider, Bernard F.

1999-01-01

Purpose: Treatment of patients with occult carcinoma of the cervix discovered after simple hysterectomy is controversial. The purpose of this review is to examine our results with postoperative radiotherapy and to compare them to similar reports and to reports of treatment with radical parametrectomy. Methods and Materials: Between November 1979 and April:, 18 patients were treated with radiotherapy at the University of Virginia for invasive carcinoma of the cervix discovered after simple hysterectomy. Simple hysterectomy was performed in all 18 patients for a variety of indications. After surgery gross residual carcinoma remained in four patients; and microscopic disease was present at the surgical margins in two patients. The remaining patients had no evidence of residual disease. All 18 patients had postoperative radiotherapy with or without brachytherapy. The endpoints for this study were local control, survival, and treatment-related toxicity. Actuarial rates were calculated using the Life method. Results: Median follow-up for all 18 patients was 42 months (range 2-202 months). Both the 5 and the 10-year actuarial local control rates were 88%. Five and 10-year actuarial overall survival rates were both 93%. Two patients had both local and distant cancer recurrences. There were no recurrences among the six patients treated with external beam alone. The remaining patients are all alive without evidence of disease, including two patients who had gross residual disease after surgery, and one patient with both microscopic positive margin and a positive lymph node (the only patient to undergo lymph node sampling). There was no severe acute morbidity and only one patient had severe late morbidity. Conclusions: Invasive carcinoma found after simple hysterectomy may be treated safely and effectively with postoperative radiotherapy. Patients with known residual disease following surgery do poorly with either radiotherapy or reoperation, but treatment with radiotherapy

Interfractional Dose Variations in Intensity-Modulated Radiotherapy With Breath-Hold for Pancreatic Cancer

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Nakamura, Mitsuhiro [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Shibuya, Keiko, E-mail: kei@kuhp.kyoto-u.ac.jp [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Nakamura, Akira [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Shiinoki, Takehiro [Department of Nuclear Engineering, Kyoto University Graduate School of Engineering, Kyoto (Japan); Matsuo, Yukinori [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Nakata, Manabu [Clinical Radiology Service Division, Kyoto University Hospital, Kyoto (Japan); Sawada, Akira; Mizowaki, Takashi; Hiraoka, Masahiro [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan)

2012-04-01

Purpose: To investigate the interfractional dose variations for intensity-modulated radiotherapy (RT) combined with breath-hold (BH) at end-exhalation (EE) for pancreatic cancer. Methods and Materials: A total of 10 consecutive patients with pancreatic cancer were enrolled. Each patient was fixed in the supine position on an individualized vacuum pillow with both arms raised. Computed tomography (CT) scans were performed before RT, and three additional scans were performed during the course of chemoradiotherapy using a conventional RT technique. The CT data were acquired under EE-BH conditions (BH-CT) using a visual feedback technique. The intensity-modulated RT plan, which used five 15-MV coplanar ports, was designed on the initial BH-CT set with a prescription dose of 39 Gy at 2.6 Gy/fraction. After rigid image registration between the initial and subsequent BH-CT scans, the dose distributions were recalculated on the subsequent BH-CT images under the same conditions as in planning. Changes in the dose-volume metrics of the gross tumor volume (GTV), clinical target volume (CTV = GTV + 5 mm), stomach, and duodenum were evaluated. Results: For the GTV and clinical target volume (CTV), the 95th percentile of the interfractional variations in the maximal dose, mean dose, dose covering 95% volume of the region of structure, and percentage of the volume covered by the 90% isodose line were within {+-}3%. Although the volume covered by the 39 Gy isodose line for the stomach and duodenum did not exceed 0.1 mL at planning, the volume covered by the 39 Gy isodose line for these structures was up to 11.4 cm{sup 3} and 1.8 cm{sup 3}, respectively. Conclusions: Despite variations in the gastrointestinal state and abdominal wall position at EE, the GTV and CTV were mostly ensured at the planned dose, with the exception of 1 patient. Compared with the duodenum, large variations in the stomach volume receiving high-dose radiation were observed, which might be beyond the

Functional Image-Guided Radiotherapy Planning in Respiratory-Gated Intensity-Modulated Radiotherapy for Lung Cancer Patients With Chronic Obstructive Pulmonary Disease

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Kimura, Tomoki, E-mail: tkkimura@hiroshima-u.ac.jp [Department of Radiation Oncology, Hiroshima University, Graduate School of Biomedical Sciences, Hiroshima City (Japan); Nishibuchi, Ikuno; Murakami, Yuji; Kenjo, Masahiro; Kaneyasu, Yuko; Nagata, Yasushi [Department of Radiation Oncology, Hiroshima University, Graduate School of Biomedical Sciences, Hiroshima City (Japan)

2012-03-15

Purpose: To investigate the incorporation of functional lung image-derived low attenuation area (LAA) based on four-dimensional computed tomography (4D-CT) into respiratory-gated intensity-modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT) in treatment planning for lung cancer patients with chronic obstructive pulmonary disease (COPD). Methods and Materials: Eight lung cancer patients with COPD were the subjects of this study. LAA was generated from 4D-CT data sets according to CT values of less than than -860 Hounsfield units (HU) as a threshold. The functional lung image was defined as the area where LAA was excluded from the image of the total lung. Two respiratory-gated radiotherapy plans (70 Gy/35 fractions) were designed and compared in each patient as follows: Plan A was an anatomical IMRT or VMAT plan based on the total lung; Plan F was a functional IMRT or VMAT plan based on the functional lung. Dosimetric parameters (percentage of total lung volume irradiated with {>=}20 Gy [V20], and mean dose of total lung [MLD]) of the two plans were compared. Results: V20 was lower in Plan F than in Plan A (mean 1.5%, p = 0.025 in IMRT, mean 1.6%, p = 0.044 in VMAT) achieved by a reduction in MLD (mean 0.23 Gy, p = 0.083 in IMRT, mean 0.5 Gy, p = 0.042 in VMAT). No differences were noted in target volume coverage and organ-at-risk doses. Conclusions: Functional IGRT planning based on LAA in respiratory-guided IMRT or VMAT appears to be effective in preserving a functional lung in lung cancer patients with COPD.

Can Intensity-Modulated Radiotherapy Preserve Oral Health-Related Quality of Life of Nasopharyngeal Carcinoma Patients?

International Nuclear Information System (INIS)

Pow, Edmond H.N.; Kwong, Dora L.W.; Sham, Jonathan S.T.; Lee, Victor H.F.; Ng, Sherry C.Y.

2012-01-01

Purpose: To investigate the changes in salivary function and oral health-related quality of life for patients with nasopharyngeal carcinoma treated by intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 57 patients with early-stage nasopharyngeal carcinoma received IMRT. The parotid and whole saliva flow was measured, and the Medical Outcomes Study 36-item short form, European Organization for Research and Treatment of Cancer Quality of Life questionnaire-C30, European Organization for Research and Treatment of Cancer Quality of Life questionnaire 35-item head-and-neck module, and Oral Health Impact Profile questionnaires were completed at baseline and 2, 6, 12, 18, and 24 months after IMRT. Results: Parotid saliva flow recovered fully after 1 year and maintained. Whole saliva flow recovered partially to 40% of baseline. A general trend of deterioration in most quality of life scales was observed after IMRT, followed by gradual recovery. Persistent oral-related symptoms were found 2 years after treatment. Conclusion: IMRT for early-stage nasopharyngeal carcinoma could only partially preserve the whole salivary function and oral health-related quality of life.

Can Intensity-Modulated Radiotherapy Preserve Oral Health-Related Quality of Life of Nasopharyngeal Carcinoma Patients?

Energy Technology Data Exchange (ETDEWEB)

Pow, Edmond H.N., E-mail: ehnpow@hku.hk [Oral Rehabilitation, University of Hong Kong Faculty of Dentistry, Hong Kong Special Administrative Region (China); Kwong, Dora L.W.; Sham, Jonathan S.T.; Lee, Victor H.F.; Ng, Sherry C.Y. [Department of Clinical Oncology, University of Hong Kong Li Ka Shing Faculty of Medicine, Hong Kong Special Administrative Region (Hong Kong)

2012-06-01

Purpose: To investigate the changes in salivary function and oral health-related quality of life for patients with nasopharyngeal carcinoma treated by intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 57 patients with early-stage nasopharyngeal carcinoma received IMRT. The parotid and whole saliva flow was measured, and the Medical Outcomes Study 36-item short form, European Organization for Research and Treatment of Cancer Quality of Life questionnaire-C30, European Organization for Research and Treatment of Cancer Quality of Life questionnaire 35-item head-and-neck module, and Oral Health Impact Profile questionnaires were completed at baseline and 2, 6, 12, 18, and 24 months after IMRT. Results: Parotid saliva flow recovered fully after 1 year and maintained. Whole saliva flow recovered partially to 40% of baseline. A general trend of deterioration in most quality of life scales was observed after IMRT, followed by gradual recovery. Persistent oral-related symptoms were found 2 years after treatment. Conclusion: IMRT for early-stage nasopharyngeal carcinoma could only partially preserve the whole salivary function and oral health-related quality of life.

Anal wall sparing effect of an endorectal balloon in 3D conformal and intensity-modulated prostate radiotherapy.

Science.gov (United States)

Smeenk, Robert Jan; van Lin, Emile N J Th; van Kollenburg, Peter; Kunze-Busch, Martina; Kaanders, Johannes H A M

2009-10-01

To investigate the anal wall (Awall) sparing effect of an endorectal balloon (ERB) in 3D conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for prostate cancer. In 24 patients with localized prostate carcinoma, two planning CT-scans were performed: with and without ERB. A prostate planning target volume (PTV) was defined, and the Awall was delineated, using two different methods. Three-field and 4-field 3D-CRT plans, and IMRT plans were generated with a prescription dose of 78Gy. In 144 treatment plans, the minimum dose (D(min)), maximum dose (D(max)), and mean dose (D(mean)) to the Awall were calculated, as well as the Awall volumes exposed to doses ranging from >or=20Gy to >or=70Gy (V(20)-V(70), respectively). In the 3D-CRT plans, an ERB significantly reduced D(mean), D(max), and V(30)-V(70). For IMRT all investigated dose parameters were significantly reduced by the ERB. The absolute reduction of D(mean) was 12Gy in 3D-CRT and was 7.5Gy in IMRT for both methods of Awall delineation. Application of an ERB showed a significant Awall sparing effect in both 3D-CRT and IMRT. This may lead to reduced late anal toxicity in prostate radiotherapy.

Xerostomia and quality of life after intensity-modulated radiotherapy vs. conventional radiotherapy for early-stage nasopharyngeal carcinoma: Initial report on a randomized controlled clinical trial

International Nuclear Information System (INIS)

Pow, Edmond; Kwong, Dora; McMillan, Anne S.; Wong, May; Sham, Jonathan; Leung, Lucullus; Leung, W. Keung

2006-01-01

Purpose: To compare directly the effect of intensity-modulated radiotherapy (IMRT) vs. conventional radiotherapy (CRT) on salivary flow and quality of life (QoL) in patients with early-stage nasopharyngeal carcinoma (NPC). Methods and Materials: Fifty-one patients with T2, N0/N1, M0 NPC took part in a randomized controlled clinical study and received IMRT or CRT. Stimulated whole (SWS) and parotid (SPS) saliva flow were measured and Medical Outcomes Short Form 36 (SF-36), European Organization for Research and Treatment of Cancer (EORTC) core quetionnaire, and EORTC head-and-neck module (QLQ-H and N35) were completed at baseline and 2, 6, and 12 months after radiotherapy. Results: Forty-six patients (88%) were in disease remission 12 months after radiotherapy. At 12 months postradiotherapy, 12 (50.0%) and 20 patients (83.3%) in the IMRT group had recovered at least 25% of preradiotherapy SWS and SPS flow respectively, compared with 1 (4.8%) and 2 patients (9.5%), respectively, in the CRT group. Global health scores showed continuous improvement in QoL after both treatments (p < 0.001). However, after 12 months subscale scores for role-physical, bodily pain, and physical function were significantly higher in the IMRT group, indicating a better condition (p < 0.05). Dry mouth and sticky saliva were problems in both groups 2 months after treatment. In the IMRT group, there was consistent improvement over time with xerostomia-related symptoms significantly less common than in the CRT group at 12 months postradiotherapy. Conclusions: IMRT was significantly better than CRT in terms of parotid sparing and improved QoL for early-stage disease. The findings support the case for assessment of health-related QoL in relation to head-and-neck cancer using a site-specific approach

Postoperative high-dose pelvic radiotherapy for N+ prostate cancer: Toxicity and matched case comparison with postoperative prostate bed-only radiotherapy

International Nuclear Information System (INIS)

Van Praet, Charles; Ost, Piet; Lumen, Nicolaas; De Meerleer, Gert; Vandecasteele, Katrien; Villeirs, Geert; Decaestecker, Karel; Fonteyne, Valérie

2013-01-01

Purpose: To report on toxicity of postoperative high-dose whole-pelvis radiotherapy (WPRT) with androgen deprivation therapy for lymph node metastasized (N1) prostate cancer (PC). To perform a matched-case analysis to compare this toxicity profile to postoperative prostate bed-only radiotherapy (PBRT). Materials and methods: Forty-eight N1-PC patients were referred for WPRT and 239 node-negative patients for PBRT. Patients were matched 1:1 according to pre-treatment demographics, symptoms, treatment and tumor characteristics. Mean dose to the prostate bed was 75 Gy (WPRT–PBRT) and 54 Gy to the elective nodes (WPRT) in 36 or 37 fractions. End points are genito-urinary (GU) and gastro-intestinal (GI) toxicity. Results: After WPRT, 35% developed grade 2 (G2) and 4% G3 acute GU toxicity. Acute GI toxicity developed in 42% (G2). Late GU toxicity developed in 36% (G2) and 7% (G3). One patient had G4 incontinence. Recuperation occurred in 59%. Late GI toxicity developed in 25% (G2) with 100% recuperation. Incidence of acute and late GI toxicity was higher following WPRT compared to PBRT (p ⩽ 0.041). GU toxicity was similar. With WPRT mean dose to bladder and rectosigmoid were higher. Conclusions: Postoperative high-dose WPRT comes at the cost of a temporary increase in G2. GI toxicity compared to PBRT because larger volumes of rectosigmoid are irradiated

A randomized, controlled, multicenter study comparing intensity-modulated radiotherapy plus concurrent chemotherapy with chemotherapy alone in gastric cancer patients with D2 resection

International Nuclear Information System (INIS)

Zhu Weiguo; Xua Dafu; Pu, Jun; Zong, Cheng-dong; Li, Tao; Tao, Guang-zhou; Ji, Fu-zhi; Zhou, Xi-lei; Han, Ji-hua; Wang, Cheng-shi; Yu, Chang-hua; Yi, Jiang-guo; Su, Xi-long; Ding, Jin-xia

2012-01-01

Background and purpose: The role of postoperative chemoradiotherapy in the treatment of patients with gastric cancer with D2 lymph node curative dissection is not well established. In this study, we compared postoperative intensity-modulated radiotherapy plus chemotherapy (IMRT-C) with chemotherapy-only in this patient population. Materials and methods: We randomly assigned patients with D2 lymph node dissection in gastric cancer to IMRT-C or chemotherapy-only groups. The adjuvant IMRT-C consisted of 400 mg of fluorouracil per square meter of body-surface area per day plus 20 mg of leucovorin per square meter of body-surface area per day for 5 days, followed by 45 Gy of IMRT for 5 weeks, with fluorouracil and leucovorin on the first 4 and the last 3 days of radiotherapy. Two 5-day cycles of fluorouracil and leucovorin were given 4 weeks after the completion of IMRT. Chemotherapy-only group was given the same chemotherapy regimens as IMRT-C group. Results: The median overall survival (OS) in the chemotherapy-only group was 48 months, as compared with 58 months in the IMRT-C group; the hazard ratio for death was 1.24 (95% confidence interval, 0.94–1.65; P = 0.122). IMRT-C was associated with increases in the median duration of recurrence-free survival (RFS) (36 months vs. 50 months), the hazard ratio for recurrence was 1.35 (95% confidence interval, 1.03–1.78; P = 0.029). COX multivariate regression analysis showed that lymph node metastasis and TNM stage were both the independent prognostic factors. Rates of all grade adverse events were similar in the two treatment groups. Conclusions: IMRT-C improved RFS, but did not significantly improve OS among patients with D2 lymph node dissection in gastric cancer. Using IMRT plus chemotherapy was feasible and well tolerated in patients with gastric cancer after D2 resection.

Intensity-Modulated Radiotherapy is Associated With Improved Global Quality of Life Among Long-term Survivors of Head-and-Neck Cancer

International Nuclear Information System (INIS)

Chen, Allen M.; Farwell, D. Gregory; Luu, Quang; Vazquez, Esther G.; Lau, Derick H.; Purdy, James A.

2012-01-01

Purpose: To compare the long-term quality of life among patients treated with and without intensity-modulated radiotherapy (IMRT) for head-and-neck cancer. Methods and Materials: University of Washington Quality of Life instrument scores were reviewed for 155 patients previously treated with radiation therapy for locally advanced head-and-neck cancer. All patients were disease free and had at least 2 years of follow-up. Eighty-four patients (54%) were treated with IMRT. The remaining 71 patients (46%) were treated with three-dimensional conformal radiotherapy (3D CRT) by use of initial opposed lateral fields matched to a low anterior neck field. Results: The mean global quality of life scores were 67.5 and 80.1 for the IMRT patients at 1 and 2 years, respectively, compared with 55.4 and 57.0 for the 3D CRT patients, respectively (p < 0.001). At 1 year after the completion of radiation therapy, the proportion of patients who rated their global quality of life as “very good” or “outstanding” was 51% and 41% among patients treated by IMRT and 3DCRT, respectively (p = 0.11). At 2 years, the corresponding percentages increased to 73% and 49%, respectively (p < 0.001). On multivariate analysis accounting for sex, age, radiation intent (definitive vs. postoperative), radiation dose, T stage, primary site, use of concurrent chemotherapy, and neck dissection, the use of IMRT was the only variable independently associated with improved quality of life (p = 0.01). Conclusion: The early quality of life improvements associated with IMRT not only are maintained but apparently become more magnified over time. These data provide powerful evidence attesting to the long-term benefits of IMRT for head-and-neck cancer.

Quality of Life After Hypofractionated Concomitant Intensity-Modulated Radiotherapy Boost for High-Risk Prostate Cancer

International Nuclear Information System (INIS)

Quon, Harvey; Cheung, Patrick C.F.; Loblaw, D. Andrew; Morton, Gerard; Pang, Geordi; Szumacher, Ewa; Danjoux, Cyril; Choo, Richard; Kiss, Alex; Mamedov, Alexandre; Deabreu, Andrea

2012-01-01

Purpose: To evaluate the change in health-related quality of life (QOL) of patients with high-risk prostate cancer treated using hypofractionated radiotherapy combined with long-term androgen deprivation therapy. Methods and Materials: A prospective Phase I–II study enrolled patients with any of the following: clinical Stage T3 disease, prostate-specific antigen level ≥20 ng/mL, or Gleason score 8–10. Radiotherapy consisted of 45 Gy (1.8 Gy per fraction) to the pelvic lymph nodes with a concomitant 22.5 Gy intensity-modulated radiotherapy boost to the prostate, for a total of 67.5 Gy (2.7 Gy per fraction) in 25 fractions over 5 weeks. Daily image guidance was performed using three gold seed fiducials. Quality of life was measured using the Expanded Prostate Cancer Index Composite (EPIC), a validated tool that assesses four primary domains (urinary, bowel, sexual, and hormonal). Results: From 2004 to 2007, 97 patients were treated. Median follow-up was 39 months. Compared with baseline, at 24 months there was no statistically significant change in the mean urinary domain score (p = 0.99), whereas there were decreases in the bowel (p < 0.01), sexual (p < 0.01), and hormonal (p < 0.01) domains. The proportion of patients reporting a clinically significant difference in EPIC urinary, bowel, sexual, and hormonal scores at 24 months was 27%, 31%, 55%, and 60%, respectively. However, moderate and severe distress related to these symptoms was minimal, with increases of only 3% and 5% in the urinary and bowel domains, respectively. Conclusions: Hypofractionated radiotherapy combined with long-term androgen deprivation therapy was well tolerated. Although there were modest rates of clinically significant patient-reported urinary and bowel toxicity, most of this caused only mild distress, and moderate and severe effects on QOL were limited. Additional follow-up is ongoing to characterize long-term QOL.

Impact of gantry rotation time on plan quality and dosimetric verification. Volumetric modulated arc therapy (VMAT) vs. intensity modulated radiotherapy (IMRT)

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Pasler, Marlies; Wirtz, Holger; Lutterbach, Johannes [Gemeinschaftspraxis fuer Strahlentherapie Singen-Friedrichshafen, Singen (Germany)

2011-12-15

To compare plan quality criteria and dosimetric accuracy of step-and-shoot intensity-modulated radiotherapy (ss-IMRT) and volumetric modulated arc radiotherapy (VMAT) using two different gantry rotation times. This retrospective planning study based on 20 patients was comprised of 10 prostate cancer (PC) and 10 head and neck (HN) cancer cases. Each plan contained two target volumes: a primary planning target volume (PTV) and a boost volume. For each patient, one ss-IMRT plan and two VMAT plans at 90 s (VMAT90) and 120 s (VMAT120) per arc were generated with the Pinnacle {sup copyright} planning system. Two arcs were provided for the PTV plans and a single arc for boost volumes. Dosimetric verification of the plans was performed using a 2D ionization chamber array placed in a full scatter phantom. VMAT reduced delivery time and monitor units for both treatment sites compared to IMRT. VMAT120 vs. VMAT90 increased delivery time and monitor units in PC plans without improving plan quality. For HN cases, VMAT120 provided comparable organs at risk sparing and better target coverage and conformity than VMAT90. In the VMAT plan verification, an average of 97.1% of the detector points passed the 3 mm, 3% {gamma} criterion, while in IMRT verification it was 98.8%. VMAT90, VMAT120, and IMRT achieved comparable treatment plans. Slower gantry movement in VMAT120 plans only improves dosimetric quality for highly complex targets.

Impact of gantry rotation time on plan quality and dosimetric verification. Volumetric modulated arc therapy (VMAT) vs. intensity modulated radiotherapy (IMRT)

International Nuclear Information System (INIS)

Pasler, Marlies; Wirtz, Holger; Lutterbach, Johannes

2011-01-01

To compare plan quality criteria and dosimetric accuracy of step-and-shoot intensity-modulated radiotherapy (ss-IMRT) and volumetric modulated arc radiotherapy (VMAT) using two different gantry rotation times. This retrospective planning study based on 20 patients was comprised of 10 prostate cancer (PC) and 10 head and neck (HN) cancer cases. Each plan contained two target volumes: a primary planning target volume (PTV) and a boost volume. For each patient, one ss-IMRT plan and two VMAT plans at 90 s (VMAT90) and 120 s (VMAT120) per arc were generated with the Pinnacle copyright planning system. Two arcs were provided for the PTV plans and a single arc for boost volumes. Dosimetric verification of the plans was performed using a 2D ionization chamber array placed in a full scatter phantom. VMAT reduced delivery time and monitor units for both treatment sites compared to IMRT. VMAT120 vs. VMAT90 increased delivery time and monitor units in PC plans without improving plan quality. For HN cases, VMAT120 provided comparable organs at risk sparing and better target coverage and conformity than VMAT90. In the VMAT plan verification, an average of 97.1% of the detector points passed the 3 mm, 3% γ criterion, while in IMRT verification it was 98.8%. VMAT90, VMAT120, and IMRT achieved comparable treatment plans. Slower gantry movement in VMAT120 plans only improves dosimetric quality for highly complex targets.

Treatment of nasal cavity and paranasal sinus cancer with modern radiotherapy techniques in the postoperative setting-the MSKCC experience

International Nuclear Information System (INIS)

Hoppe, Bradford S.; Stegman, Lauren D.; Zelefsky, Michael J.; Rosenzweig, Kenneth E.; Wolden, Suzanne L.; Patel, Snehal G.; Shah, Jatin P.; Kraus, Dennis H.; Lee, Nancy Y.

2007-01-01

Purpose: To perform a retrospective analysis of patients with paranasal sinus (PNS) cancer treated with postoperative radiotherapy (RT) at Memorial Sloan-Kettering Cancer Center. Methods and Materials: Between January 1987 and July 2005, 85 patients with PNS and nasal cavity cancer underwent postoperative RT. Most patients had squamous cell carcinoma (49%; n = 42), T4 tumors (52%; n = 36), and the maxillary sinus (53%; n = 45) as the primary disease site. The median radiation dose was 63 Gy. Of the 85 patients, 76 underwent CT simulation and 53 were treated with either three-dimensional conformal RT (27%; n = 23) or intensity-modulated RT (35%; n = 30). Acute and late toxicities were scored according to the Radiation Therapy Oncology Group radiation morbidity scoring criteria. Results: With a median follow-up for surviving patients of 60 months, the 5-year estimates of local progression-free, regional progression-free, distant metastasis-free, disease-free, and overall survival rates were 62%, 87%, 82%, 55%, and 67%, respectively. On multivariate analysis, squamous cell histology and cribriform plate involvement predicted for an increased likelihood of local recurrence, and squamous cell histologic features predicted for worse overall survival. None of the patients who underwent CT simulation and were treated with modern techniques developed a Grade 3-4 late complication of the eye. Conclusion: Complete surgical resection followed by adjuvant RT is an effective and safe approach in the treatment of PNS cancer. Emerging tools, such as three-dimensional conformal treatment and, in particular, intensity-modulated RT for PNS tumors, may minimize the occurrence of late complications associated with conventional RT techniques. Local recurrence remains a significant problem

Intensity modulated radiotherapy with fixed collimator jaws for locoregional left-sided breast cancer irradiation.

Science.gov (United States)

Wang, Juanqi; Yang, Zhaozhi; Hu, Weigang; Chen, Zhi; Yu, Xiaoli; Guo, Xiaomao

2017-05-16

The purpose of this study is to evaluate the intensity modulated radiotherapy (IMRT) with the fixed collimator jaws technique (FJT) for the left breast and regional lymph node. The targeted breast tissue and the lymph nodes, and the normal tissues were contoured for 16 left-sided breast cancer patients previously treated with radiotherapy after lumpectomy. For each patient, treatment plans using different planning techniques, i.e., volumetric modulated arc therapy (VMAT), tangential IMRT (tangential-IMRT), and IMRT with FJT (FJT-IMRT) were developed for dosimetric comparisons. A dose of 50Gy was prescribed to the planning target volume. The dose-volume histograms were generated, and the paired t-test was used to analyze the dose differences. FJT-IMRT had similar mean heart volume receiving 30Gy (V30 Gy) with tangential-IMRT (1.5% and 1.6%, p = 0.41), but inferior to the VMAT (0.8%, p < 0.001). In the average heart mean dose comparison, FJT-IMRT had the lowest value, and it was 0.6Gy lower than that for the VMAT plans (p < 0.01). A significant dose increase in the contralateral breast and lung was observed in VMAT plans. Compared with tangential-IMRT and VMAT plans, FJT-IMRT reduced the mean dose of thyroid, humeral head and cervical esophageal by 47.6% (p < 0.01) and 45.7% (p < 0.01), 74.3% (p =< 0.01) and 73% (p =< 0.01), and 26.7% (p =< 0.01) and 29.2% (p =< 0.01). In conclusion, compared with tangential-IMRT and VMAT, FJT-IMRT plan has the lowest thyroid, humeral head and cervical esophageal mean dose and it can be a reasonable treatment option for a certain subgroup of patients, such as young left-breast cancer patients and/or patients with previous thyroid disease.

Consensus Guidelines for Delineation of Clinical Target Volume for Intensity-Modulated Pelvic Radiotherapy for the Definitive Treatment of Cervix Cancer

International Nuclear Information System (INIS)

Lim, Karen; Small, William; Portelance, Lorraine; Creutzberg, Carien; Juergenliemk-Schulz, Ina M.; Mundt, Arno; Mell, Loren K.; Mayr, Nina; Viswanathan, Akila; Jhingran, Anuja; Erickson, Beth; De Los Santos, Jennifer; Gaffney, David; Yashar, Catheryn; Beriwal, Sushil; Wolfson, Aaron

2011-01-01

Purpose: Accurate target definition is vitally important for definitive treatment of cervix cancer with intensity-modulated radiotherapy (IMRT), yet a definition of clinical target volume (CTV) remains variable within the literature. The aim of this study was to develop a consensus CTV definition in preparation for a Phase 2 clinical trial being planned by the Radiation Therapy Oncology Group. Methods and Materials: A guidelines consensus working group meeting was convened in June 2008 for the purposes of developing target definition guidelines for IMRT for the intact cervix. A draft document of recommendations for CTV definition was created and used to aid in contouring a clinical case. The clinical case was then analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with kappa statistics as a measure of agreement between participants. Results: Nineteen experts in gynecological radiation oncology generated contours on axial magnetic resonance images of the pelvis. Substantial STAPLE agreement sensitivity and specificity values were seen for gross tumor volume (GTV) delineation (0.84 and 0.96, respectively) with a kappa statistic of 0.68 (p < 0.0001). Agreement for delineation of cervix, uterus, vagina, and parametria was moderate. Conclusions: This report provides guidelines for CTV definition in the definitive cervix cancer setting for the purposes of IMRT, building on previously published guidelines for IMRT in the postoperative setting.

The pitfalls of dosimetric commissioning for intensity modulated radiation therapy

International Nuclear Information System (INIS)

Tohyama, Naoki; Kodama, Takashi; Hatano, K.

2013-01-01

Intensity modulated radiation therapy (IMRT) allows higher radiation dose to be focused to the target volumes while minimizing the dose to OAR. To start of clinical treatment in IMRTvwe must perform commissioning strictly than 3D-conformal radiotherapy (CRT). In this report, pitfalls of dosimetric commissioning for intensity modulated radiation therapy were reviewed. Multileaf collimator (MLC) offsets and MLC transmissions are important parameters in commissioning of RTPS for IMRT. Correction of depth scaling and fluence scaling is necessary for dose measurement using solid phantom. (author)

Randomized clinical trial of post-operative radiotherapy versus concomitant carboplatin and radiotherapy for head and neck cancers with lymph node involvement

International Nuclear Information System (INIS)

Racadot, Severine; Mercier, Mariette; Dussart, Sophie; Dessard-Diana, Bernadette; Bensadoun, Rene-Jean; Martin, Michel; Malaurie, Emmanuelle; Favrel, Veronique; Housset, Martin; Durdux, Catherine; Journel, Catherine; Calais, Gilles; Huet, Jocelyne; Pillet, Gerard; Hennequin, Christophe; Haddad, Elias; Diana, Christian; Blaska-Jaulerry, Brigitte; Henry-Amar, Michel; Gehanno, Pierre

2008-01-01

Background and purpose: Post-operative radiotherapy is indicated for the treatment of head and neck cancers. In vitro, chemotherapy potentiates the cytotoxic effects of radiation. We report the results of a randomized trial testing post-operative radiotherapy alone versus concomitant carboplatin and radiotherapy for head and neck cancers with lymph node involvement. Materials and methods: The study involved patients undergoing curative-intent surgery for head and neck cancers with histological evidence of lymph node involvement. Patients were randomly assigned to receive radiotherapy alone (54-72 Gy, 30-40 fractions, 6-8 weeks) or identical treatment plus concomitant Carboplatin (50 mg/m 2 administered by IV infusion twice weekly). Results: Between February 1994 and June 2002, 144 patients were included. With a median follow-up of 106 months (95% confidence interval (CI) [92-119]), the 2-year rate of loco-regional control was 73% (95% CI: 0.61-0.84) in the combined treatment group and 68% (95% CI: 0.57-0.80) in the radiotherapy group (p = 0.26). Overall survival did not differ significantly between groups (hazard ratio for death, 1.05; 95% CI: 0.69-1.60; p = 0.81). Conclusions: Twice-weekly administration of carboplatin concomitant to post-operative radiotherapy did not improve local control or overall survival rates in this population of patients with node-positive head and neck cancers

The importance of prostate bed tilt during postprostatectomy intensity-modulated radiotherapy

International Nuclear Information System (INIS)

Bell, Linda J.; Cox, Jennifer; Eade, Thomas; Rinks, Marianne; Kneebone, Andrew

2014-01-01

Variations in rectal and bladder filling can create a tilt of the prostate bed, which generates the potential for a geographic miss during postprostatectomy radiotherapy. The aim of this study is to assess the effect that bladder and rectum filling has on planning target volume angle, to determine a method to assess prostate bed tilt leading to potential geographic miss, and to discuss possible implementation issues. The cone-beam computed tomography images (n = 377) of 40 patients who received postprostatectomy radiotherapy with intensity-modulated radiotherapy were reviewed. The amount of tilt in the prostate bed was defined as the angle change between 2 surgical clips, one in the upper prostate bed and another in the lower. A potential geographic miss was defined as movement of any clip of more than 1 cm in any direction or 0.5 cm posteriorly when aligned to bone anatomy. Variations in bladder and rectum size were correlated with the degree of prostate bed tilt, and the rate of potential geographic miss was determined. A possible clinical use of prostate bed tilt was then assessed for different imaging techniques. A tilt of more than 10° was seen in 20.2% of images, which resulted in a 57.9% geographic miss rate of the superior clip. When tilt remained within 10°, there was only a 9% rate of geographic miss. Potential geographic miss of the inferior surgical clip was rare, occurring in only 1.9% of all images reviewed. The most common occurrence when the prostate bed tilt increased by more than 10° was a smaller bladder and larger rectum (6.4% of all images). The most common occurrence when the prostate bed tilt decreased by more than 10° was a larger bladder and smaller rectum (1.3% of all images). Significant prostate bed tilt (>± 10°) occurred in more than 20% of images, creating a 58% rate of geographic miss. Greatest prostate bed tilt occurred when the bladder size increased or reduced by more than 2 cm or the superior rectum size increased by more

The importance of prostate bed tilt during postprostatectomy intensity-modulated radiotherapy

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Bell, Linda J., E-mail: Linda.Bell1@health.nsw.gov.au [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Faculty of Health Sciences, University of Sydney, Lidcombe, New South Wales (Australia); Cox, Jennifer [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Faculty of Health Sciences, University of Sydney, Lidcombe, New South Wales (Australia); Eade, Thomas; Rinks, Marianne; Kneebone, Andrew [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St Leonards, New South Wales (Australia)

2014-10-01

Variations in rectal and bladder filling can create a tilt of the prostate bed, which generates the potential for a geographic miss during postprostatectomy radiotherapy. The aim of this study is to assess the effect that bladder and rectum filling has on planning target volume angle, to determine a method to assess prostate bed tilt leading to potential geographic miss, and to discuss possible implementation issues. The cone-beam computed tomography images (n = 377) of 40 patients who received postprostatectomy radiotherapy with intensity-modulated radiotherapy were reviewed. The amount of tilt in the prostate bed was defined as the angle change between 2 surgical clips, one in the upper prostate bed and another in the lower. A potential geographic miss was defined as movement of any clip of more than 1 cm in any direction or 0.5 cm posteriorly when aligned to bone anatomy. Variations in bladder and rectum size were correlated with the degree of prostate bed tilt, and the rate of potential geographic miss was determined. A possible clinical use of prostate bed tilt was then assessed for different imaging techniques. A tilt of more than 10° was seen in 20.2% of images, which resulted in a 57.9% geographic miss rate of the superior clip. When tilt remained within 10°, there was only a 9% rate of geographic miss. Potential geographic miss of the inferior surgical clip was rare, occurring in only 1.9% of all images reviewed. The most common occurrence when the prostate bed tilt increased by more than 10° was a smaller bladder and larger rectum (6.4% of all images). The most common occurrence when the prostate bed tilt decreased by more than 10° was a larger bladder and smaller rectum (1.3% of all images). Significant prostate bed tilt (>± 10°) occurred in more than 20% of images, creating a 58% rate of geographic miss. Greatest prostate bed tilt occurred when the bladder size increased or reduced by more than 2 cm or the superior rectum size increased by more

Simultaneous integrated boost intensity-modulated radiotherapy versus 3-dimensional conformal radiotherapy in preoperative concurrent chemoradiotherapy for locally advanced rectal cancer

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Bae, Bong Kyung; Kang, Min Kyul; Kim, Jae Chul [Dept. of Radiation Oncology, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Kim, Min Young; Choi, Gyu Seog; Kim, Jong Gwang; Kang, Byung Woog; Kim, Hye Jin; Park, Soo Yeun [Kyungpook National University Chilgok Hospital, Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

2017-09-15

To evaluate the feasibility of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for preoperative concurrent chemoradiotherapy (PCRT) in locally advanced rectal cancer (LARC), by comparing with 3-dimensional conformal radiotherapy (3D-CRT). Patients who were treated with PCRT for LARC from 2015 January to 2016 December were retrospectively enrolled. Total doses of 45 Gy to 50.4 Gy with 3D-CRT or SIB-IMRT were administered concomitantly with 5-fluorouracil plus leucovorin or capecitabine. Surgery was performed 8 weeks after PCRT. Between PCRT and surgery, one cycle of additional chemotherapy was administered. Pathologic tumor responses were compared between SIB-IMRT and 3D-CRT groups. Acute gastrointestinal, genitourinary, hematologic, and skin toxicities were compared between the two groups based on the RTOG toxicity criteria. SIB-IMRT was used in 53 patients, and 3D-CRT in 41 patients. After PCRT, no significant differences were noted in tumor responses, pathologic complete response (9% vs. 7%; p = 1.000), pathologic tumor regression Grade 3 or higher (85% vs. 71%; p = 0.096), and R0 resection (87% vs. 85%; p = 0.843). Grade 2 genitourinary toxicities were significantly lesser in the SIB-IMRT group (8% vs. 24%; p = 0.023), but gastrointestinal toxicities were not different across the two groups. SIB-IMRT showed lower GU toxicity and similar tumor responses when compared with 3D-CRT in PCRT for LARC.

Intensity-modulated radiotherapy (IMRT) for carcinoma of the maxillary sinus: A comparison of IMRT planning systems

International Nuclear Information System (INIS)

Ahmed, Raef S.; Ove, Roger; Duan, Jun; Popple, Richard; Cobb, Glenn

2006-01-01

The treatment of maxillary sinus carcinoma with forward planning can be technically difficult when the neck also requires radiotherapy. This difficulty arises because of the need to spare the contralateral face while treating the bilateral neck. There is considerable potential for error in clinical setup and treatment delivery. We evaluated intensity-modulated radiotherapy (IMRT) as an improvement on forward planning, and compared several inverse planning IMRT platforms. A composite dose-volume histogram (DVH) was generated from a complex forward planned case. We compared the results with those generated by sliding window fixed field dynamic multileaf collimator (MLC) IMRT, using sets of coplanar beams. All setups included an anterior posterior (AP) beam, and 3-, 5-, 7-, and 9-field configurations were evaluated. The dose prescription and objective function priorities were invariant. We also evaluated 2 commercial tomotherapy IMRT delivery platforms. DVH results from all of the IMRT approaches compared favorably with the forward plan. Results for the various inverse planning approaches varied considerably across platforms, despite an attempt to prescribe the therapy similarly. The improvement seen with the addition of beams in the fixed beam sliding window case was modest. IMRT is an effective means of delivering radiotherapy reliably in the complex setting of maxillary sinus carcinoma with neck irradiation. Differences in objective function definition and optimization algorithms can lead to unexpected differences in the final dose distribution, and our evaluation suggests that these factors are more significant than the beam arrangement or number of beams

Temporal lobe injury after re-irradiation of locally recurrent nasopharyngeal carcinoma using intensity modulated radiotherapy: clinical characteristics and prognostic factors.

Science.gov (United States)

Liu, Shuai; Lu, Taixiang; Zhao, Chong; Shen, Jingxian; Tian, Yunming; Guan, Ying; Zeng, Lei; Xiao, Weiwei; Huang, Shaomin; Han, Fei

2014-09-01

Temporal lobe injury (TLI) is a debilitating complication after radiotherapy for nasopharyngeal carcinoma (NPC), especially in patients who suffer treatment relapses and receive re-irradiation. We explored the clinical characteristics and prognostic factors of TLI in locally recurrent NPC (rNPC) patients after re-irradiation using intensity modulated radiotherapy (IMRT). A total of 454 temporal lobes (TLs) from 227 locally rNPC patients were reviewed. The clinical characteristics of TLI were analyzed. In the two radiotherapy courses, the equivalent dose in 2 Gy per fraction (EQD2) for the TLs was recalculated to facilitate comparison of the individual data. The median follow-up time was 31 (range, 3-127) months. After re-irradiation using IMRT, 31.3 % (71/227) of patients developed TLI. The median latency of TLI was 15 (range, 4-100) months. Univariate and multivariate analysis showed that the interval time (IT) between the two courses of radiotherapy and the summation of the maximum doses of the two radiotherapy courses (EQD2 - ∑max) were independent factors influencing TLI. The 5-year incidence of TLI for an IT ≤26 or >26 months was 35.9 and 53.7 % respectively (p = 0.024). The median maximum doses delivered to the injured TLs were significantly higher than was the case for the uninjured TLs after two courses of radiotherapy (135.3 and 129.8 Gy, respectively: p 2-year interval was found to be relatively safe.

Distant Metastases in Head-and-Neck Squamous Cell Carcinoma Treated With Intensity-Modulated Radiotherapy

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Yao Min, E-mail: min.yao@uhhospitals.org [Department of Radiation Oncology, University Hospitals Case Medical Center, Cleveland, OH (United States); Lu Minggen [School of Public Health, University of Nevada at Reno, Reno, NV (United States); Savvides, Panayiotis S. [Department of Medicine, University Hospitals Case Medical Center, Cleveland, OH (United States); Rezaee, Rod; Zender, Chad A.; Lavertu, Pierre [Department of Otolaryngology-Head and Neck Surgery, University Hospitals Case Medical Center, Cleveland, OH (United States); Buatti, John M. [Department of Radiation Oncology, University of Iowa, Iowa City, IA (United States); Machtay, Mitchell [Department of Radiation Oncology, University Hospitals Case Medical Center, Cleveland, OH (United States)

2012-06-01

Purpose: To determine the pattern and risk factors for distant metastases in head-and-neck squamous cell carcinoma (HNSCC) after curative treatment with intensity-modulated radiotherapy (IMRT). Methods and Materials: This was a retrospective study of 284 HNSCC patients treated in a single institution with IMRT. Sites included were oropharynx (125), oral cavity (70), larynx (55), hypopharynx (17), and unknown primary (17). American Joint Committee on Cancer stage distribution includes I (3), II (19), III (42), and IV (203). There were 224 males and 60 females with a median age of 57. One hundred eighty-six patients were treated with definitive IMRT and 98 postoperative IMRT. One hundred forty-nine patients also received concurrent cisplatin-based chemotherapy. Results: The median follow-up for all patients was 22.8 months (range, 0.07-77.3 months) and 29.5 months (4.23-77.3 months) for living patients. The 3-year local recurrence-free survival, regional recurrence-free survival, locoregional recurrence-free survival, distant metastasis-free survival, and overall survival were 94.6%, 96.4%, 92.5%, 84.1%, and 68.95%, respectively. There were 45 patients with distant metastasis. In multivariate analysis, distant metastasis was strongly associated with N stage (p = 0.046), T stage (p < 0.0001), and pretreatment maximum standardized uptake value of the lymph node (p = 0.006), but not associated with age, gender, disease sites, pretreatment standardized uptake value of the primary tumor, or locoregional control. The freedom from distant metastasis at 3 years was 98.1% for no factors, 88.6% for one factor, 68.3% for two factors, and 41.7% for three factors (p < 0.0001 by log-rank test). Conclusion: With advanced radiation techniques and concurrent chemotherapy, the failure pattern has changed with more patients failing distantly. The majority of patients with distant metastases had no local or regional failures, indicating that these patients might have microscopic distant

Can All Centers Plan Intensity-Modulated Radiotherapy (IMRT) Effectively? An External Audit of Dosimetric Comparisons Between Three-Dimensional Conformal Radiotherapy and IMRT for Adjuvant Chemoradiation for Gastric Cancer

International Nuclear Information System (INIS)

Chung, Hans T.; Lee, Brian; Park, Eileen; Lu, Jiade J.; Xia Ping

2008-01-01

Purpose: To compare dosimetric endpoints between three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) at our center with limited IMRT experience, and to perform an external audit of the IMRT plans. Methods and Materials: Ten patients, who received adjuvant chemoradiation for gastric cancer, formed the study cohort. For standardization, the planning target volume (PTV) and organs at risk were recontoured with the assistance of a study protocol radiologic atlas. The cohort was replanned with CMS Xio to generate coplanar 3D-CRT and IMRT plans. All 10 datasets, including volumes but without the plans (i.e., blinded), were transmitted to an experienced center where IMRT plans were designed using Nomos Corvus (IMRT-C) and ADAC Pinnacle (IMRT-P). All IMRT plans were normalized to D95% receiving 45 Gy. Results: Intensity-modulated radiotherapy yielded higher PTV V45 (volume that receives ≥45 Gy) (p < 0.001) than 3D-CRT. No difference in V20 was seen in the right (p = 0.9) and left (p 0.3) kidneys, but the liver mean dose (p < 0.001) was superior with IMRT. For the external audit, IMRT-C (p = 0.002) and IMRT-P (p < 0.001) achieved significantly lower left kidney V20 than IMRT, and IMRT-P (p < 0.001) achieved lower right kidney V20 than IMRT. The IMRT-C (p = 0.003) but not IMRT-P (p = 0.6) had lower liver mean doses than IMRT. Conclusions: At our institution with early IMRT experience, IMRT improved PTV dose coverage and liver doses but not kidney doses. An external audit of IMRT plans showed that an experienced center can yield superior IMRT plans

Clinical application of intensity and energy modulated radiotherapy with photon and electron beams

International Nuclear Information System (INIS)

Xiangkui Mu

2005-01-01

In modern, advanced radiotherapy (e.g. intensity modulated photon radiotherapy, IMXT) the delivery time for each fraction becomes prolonged to 10-20 minutes compared with the conventional, commonly 2-5 minutes. The biological effect of this prolongation is not fully known. The large number of beam directions in IMXT commonly leads to a large integral dose in the patient. Electrons would reduce the integral dose but are not suitable for treating deep-seated tumour, due to their limited penetration in tissues. By combining electron and photon beams, the dose distributions may be improved compared with either used alone. One obstacle for using electron beams in clinical routine is that there is no available treatment planning systems that optimise electron beam treatments in a similar way as for IMXT. Protons have an even more pronounced dose fall-off, larger penetration depth and less penumbra widening than electrons and are therefore more suitable for advanced radiotherapy. However, proton facilities optimised for advanced radiotherapy are not commonly available. In some instances electron beams may be an acceptable surrogate. The first part of this study is an experimental in vitro study where the situation in a tumour during fractionated radiotherapy is simulated. The effect of the prolonged fraction time is compared with the predictions by radiobiological models. The second part is a treatment planning study to analyse the mixing of electron and photon beams for at complex target volume in comparison with IMXT. In the next step a research version of an electron beam optimiser was used for the improvement of treatment plans. The aim was to develop a method for translating crude energy and intensity matrices for optimised electrons into a deliverable treatment plan without destroying the dose distribution. In the final part, different methods of treating the spinal canal in medulloblastoma were explored in a treatment planning study that was evaluated with

Anal wall sparing effect of an endorectal balloon in 3D conformal and intensity-modulated prostate radiotherapy

International Nuclear Information System (INIS)

Smeenk, Robert Jan; Lin, Emile N.J.Th. van; Kollenburg, Peter van; Kunze-Busch, Martina; Kaanders, Johannes H.A.M.

2009-01-01

Background and purpose: To investigate the anal wall (Awall) sparing effect of an endorectal balloon (ERB) in 3D conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for prostate cancer. Materials and methods: In 24 patients with localized prostate carcinoma, two planning CT-scans were performed: with and without ERB. A prostate planning target volume (PTV) was defined, and the Awall was delineated, using two different methods. Three-field and 4-field 3D-CRT plans, and IMRT plans were generated with a prescription dose of 78 Gy. In 144 treatment plans, the minimum dose (D min ), maximum dose (D max ), and mean dose (D mean ) to the Awall were calculated, as well as the Awall volumes exposed to doses ranging from ≥20 Gy to ≥70 Gy (V 20 - V 70 , respectively). Results: In the 3D-CRT plans, an ERB significantly reduced D mean , D max , and V 30 - V 70 . For IMRT all investigated dose parameters were significantly reduced by the ERB. The absolute reduction of D mean was 12 Gy in 3D-CRT and was 7.5 Gy in IMRT for both methods of Awall delineation. Conclusions: Application of an ERB showed a significant Awall sparing effect in both 3D-CRT and IMRT. This may lead to reduced late anal toxicity in prostate radiotherapy.

The Dosimetric Consequences of Intensity Modulated Radiotherapy for Cervix Cancer: The Impact of Organ Motion, Deformation and Tumour Regression

Science.gov (United States)

Lim, Karen Siah Huey

Hypothesis: In intensity modulated radiotherapy (IMRT) for cervix cancer, the dose received by the tumour target and surrounding normal tissues is significantly different to that indicated by a single static plan. Rationale: The optimal use of IMRT in cervix cancer requires a greater attention to clinical target volume (CTV) definition and tumour & normal organ motion to assure maximum tumour control with the fewest side effects. Research Aims: 1) Generate consensus CTV contouring guidelines for cervix cancer; 2) Evaluate intra-pelvic tumour and organ dynamics during radiotherapy; 3) Analyze the dose consequences of intra-pelvic organ dynamics on different radiotherapy strategies. Results: Consensus CTV definitions were generated using experts-in-the-field. Substantial changes in tumour volume and organ motion, resulted in significant reductions in accumulated dose to tumour targets and variability in accumulated dose to surrounding normal tissues. Significance: Formalized CTV definitions for cervix cancer is important in ensuring consistent standards of practice. Complex and unpredictable tumour and organ dynamics mandates daily soft-tissue image guidance if IMRT is used. To maximize the benefits of IMRT for cervix cancer, a strategy of adaptation is necessary.

Radio-induced malignancies after breast cancer postoperative radiotherapy in patients with Li-Fraumeni syndrome

International Nuclear Information System (INIS)

Heymann, Steve; Bourgier, Céline; Delaloge, Suzette; Rahal, Arslane; Caron, Olivier; Frebourg, Thierry; Barreau, Lise; Pachet, Corinne; Mathieu, Marie-Christine; Marsiglia, Hugo

2010-01-01

There are no specific recommendations for the management of breast cancer patients with germ-line p53 mutations, an exceptional genetic condition, particularly regarding postoperative radiotherapy. Preclinical data suggested that p53 mutations conferred enhanced radiosensitivity in vitro and in vivo and the few clinical observations showed that Li-Fraumeni families were at a higher risk of secondary radio-induced malignancies. We reviewed a cohort of patients with germ-line p53 mutations who had been treated for breast cancer as the first tumor event. We assessed their outcome and the incidence of secondary radio-induced malignancies. Among 47 documented Li-Fraumeni families treated from 1997 to 2007 at the Institut Gustave Roussy, 8 patients had been diagnosed with breast cancer as the first tumor event. Three patients had undergone conservative breast surgery followed by postoperative radiotherapy and five patients had undergone a mastectomy (3 with postoperative radiotherapy). Thus, 6/8 patients had received postoperative radiotherapy. Median follow-up was 6 years. Median age at the diagnosis of the primary breast cancer was 30 years. The histological characteristics were as follows: intraductal carcinoma in situ (n = 3), invasive ductal carcinoma (n = 4) and a phyllodes tumor (n = 1). Among the 6 patients who had received adjuvant radiotherapy, the following events had occurred: 3 ipsilateral breast recurrences, 3 contralateral breast cancers, 2 radio-induced cancers, and 3 new primaries (1 of which was an in-field thyroid cancer with atypical histology). In contrast, only one event had occurred (a contralateral breast cancer) among patients who had not received radiation therapy. These observations could argue in favor of bilateral mastectomy and the avoidance of radiotherapy

Intensity-Modulated Radiation Therapy for Primary Brain Tumors

Institute of Scientific and Technical Information of China (English)

Zhong-min Wang

2004-01-01

Radiation therapy has been used to treat primary brain tumors as standard primary and/or adjunctive therapies for decades. It is difficult for conventional radiotherapy to deliver a lethal dose of radiation to the tumors while sparing surrounding normal brain due to complicated structures and multifunction in human brain. With the understanding of radiation physics and computer technology, a number of novel and more precise radiotherapies have been developed in recent years. Intensity modulated radiotherapy (IMRT) is one of these strategies. The use of IMRT in the treatment of primary brain tumors is being increasing nowadays. It shows great promise for some of primary brain tumors and also presents some problems, This review highlights current IMRT in the treatment of mainly primary brain tumors.

Toxicity and dosimetric analysis of non-small cell lung cancer patients undergoing radiotherapy with 4DCT and image-guided intensity modulated radiotherapy: a regional centre's experience.

Science.gov (United States)

Livingston, Gareth C; Last, Andrew J; Shakespeare, Thomas P; Dwyer, Patrick M; Westhuyzen, Justin; McKay, Michael J; Connors, Lisa; Leader, Stephanie; Greenham, Stuart

2016-09-01

For patients receiving radiotherapy for locally advance non-small cell lung cancer (NSCLC), the probability of experiencing severe radiation pneumonitis (RP) appears to rise with an increase in radiation received by the lungs. Intensity modulated radiotherapy (IMRT) provides the ability to reduce planned doses to healthy organs at risk (OAR) and can potentially reduce treatment-related side effects. This study reports toxicity outcomes and provides a dosimetric comparison with three-dimensional conformal radiotherapy (3DCRT). Thirty curative NSCLC patients received radiotherapy using four-dimensional computed tomography and five-field IMRT. All were assessed for early and late toxicity using common terminology criteria for adverse events. All plans were subsequently re-planned using 3DCRT to the same standard as the clinical plans. Dosimetric parameters for lungs, oesophagus, heart and conformity were recorded for comparison between the two techniques. IMRT plans achieved improved high-dose conformity and reduced OAR doses including lung volumes irradiated to 5-20 Gy. One case each of oesophagitis and erythema (3%) were the only Grade 3 toxicities. Rates of Grade 2 oesophagitis were 40%. No cases of Grade 3 RP were recorded and Grade 2 RP rates were as low as 3%. IMRT provides a dosimetric benefit when compared to 3DCRT. While the clinical benefit appears to increase with increasing target size and increasing complexity, IMRT appears preferential to 3DCRT in the treatment of NSCLC.

Postoperative radiotherapy in patients with salivary duct carcinoma. Clinical outcomes and prognostic factors

International Nuclear Information System (INIS)

Shinoto, Makoto; Shioyama, Yoshiyuki; Nakamura, Katsumasa

2013-01-01

This study sought to investigate the clinical outcome and the role of postoperative radiotherapy for patients with salivary duct carcinoma (SDC) who had undergone surgery and postoperative radiotherapy. We performed a retrospective analysis of 25 SDC patients treated between 1998 and 2011 with surgery and postoperative radiotherapy. The median prescribed dose was 60 Gy (range, 49.5-61.4 Gy). The clinical target volume (CTV) was defined as the tumor bed in four patients, the tumor bed and ipsilateral neck in 14 patients, and the tumor bed and bilateral neck in six patients. Local control (LC), disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and prognostic variables were analyzed with the log-rank test. The 5-year LC, DFS and OS were 67%, 45% and 47%, respectively. Disease recurrence was found in 12 patients: seven as local, four as regional and eight as distant failure. Perineural and lymphovascular invasion was a significant prognostic factor for LC (P=0.03). Local failure was common, and the presence of local recurrence significantly affected the OS (P<0.05). We conclude that surgery and postoperative radiotherapy is expected to decrease the risk of local failure and contribute to good prognoses for patients with SDC. It might be advisable to have the CTV include the cranial nerves involved and the corresponding parts of the skull base in cases of pathologically positive perineural invasion. (author)

SU-F-T-342: Dosimetric Constraint Prediction Guided Automatic Mulit-Objective Optimization for Intensity Modulated Radiotherapy

International Nuclear Information System (INIS)

Song, T; Zhou, L; Li, Y

2016-01-01

Purpose: For intensity modulated radiotherapy, the plan optimization is time consuming with difficulties of selecting objectives and constraints, and their relative weights. A fast and automatic multi-objective optimization algorithm with abilities to predict optimal constraints and manager their trade-offs can help to solve this problem. Our purpose is to develop such a framework and algorithm for a general inverse planning. Methods: There are three main components contained in this proposed multi-objective optimization framework: prediction of initial dosimetric constraints, further adjustment of constraints and plan optimization. We firstly use our previously developed in-house geometry-dosimetry correlation model to predict the optimal patient-specific dosimetric endpoints, and treat them as initial dosimetric constraints. Secondly, we build an endpoint(organ) priority list and a constraint adjustment rule to repeatedly tune these constraints from their initial values, until every single endpoint has no room for further improvement. Lastly, we implement a voxel-independent based FMO algorithm for optimization. During the optimization, a model for tuning these voxel weighting factors respecting to constraints is created. For framework and algorithm evaluation, we randomly selected 20 IMRT prostate cases from the clinic and compared them with our automatic generated plans, in both the efficiency and plan quality. Results: For each evaluated plan, the proposed multi-objective framework could run fluently and automatically. The voxel weighting factor iteration time varied from 10 to 30 under an updated constraint, and the constraint tuning time varied from 20 to 30 for every case until no more stricter constraint is allowed. The average total costing time for the whole optimization procedure is ∼30mins. By comparing the DVHs, better OAR dose sparing could be observed in automatic generated plan, for 13 out of the 20 cases, while others are with competitive

SU-F-T-342: Dosimetric Constraint Prediction Guided Automatic Mulit-Objective Optimization for Intensity Modulated Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Song, T; Zhou, L [Southern Medical University, Guangzhou, Guangdong (China); Li, Y [Beihang University, Beijing, Beijing (China)

2016-06-15

Purpose: For intensity modulated radiotherapy, the plan optimization is time consuming with difficulties of selecting objectives and constraints, and their relative weights. A fast and automatic multi-objective optimization algorithm with abilities to predict optimal constraints and manager their trade-offs can help to solve this problem. Our purpose is to develop such a framework and algorithm for a general inverse planning. Methods: There are three main components contained in this proposed multi-objective optimization framework: prediction of initial dosimetric constraints, further adjustment of constraints and plan optimization. We firstly use our previously developed in-house geometry-dosimetry correlation model to predict the optimal patient-specific dosimetric endpoints, and treat them as initial dosimetric constraints. Secondly, we build an endpoint(organ) priority list and a constraint adjustment rule to repeatedly tune these constraints from their initial values, until every single endpoint has no room for further improvement. Lastly, we implement a voxel-independent based FMO algorithm for optimization. During the optimization, a model for tuning these voxel weighting factors respecting to constraints is created. For framework and algorithm evaluation, we randomly selected 20 IMRT prostate cases from the clinic and compared them with our automatic generated plans, in both the efficiency and plan quality. Results: For each evaluated plan, the proposed multi-objective framework could run fluently and automatically. The voxel weighting factor iteration time varied from 10 to 30 under an updated constraint, and the constraint tuning time varied from 20 to 30 for every case until no more stricter constraint is allowed. The average total costing time for the whole optimization procedure is ∼30mins. By comparing the DVHs, better OAR dose sparing could be observed in automatic generated plan, for 13 out of the 20 cases, while others are with competitive

SU-F-P-52: A Meta-Analysis of Controlled Clinical Trials Comparing Elective Nodal Irradiation with Involved-Field Irradiation for Conformal Or Intensity-Modulated Radiotherapy in Patients with Esophageal Cancer

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Bai, W; Zhang, R; Zhou, Z; Qiao, X [The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei (China)

2016-06-15

Purpose: To compare elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer by a metaanalysis. Methods: Wanfang, CNKI, VIP, CBM databases, PubMed, Embase and Cochrane Library were searched to identify the controlled clinical trials of elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. The obtained data were analyzed using Stata 11.0. The difference between two groups was estimated by calculating the odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of 12 controlled clinical trials involving 1095 esophageal cancer patients, which were selected according to inclusion and exclusion criteria, were included in this meta-analysis. The meta-analysis showed that the elective nodal irradiation group reduced the rates of out-field failure comparing with involved-field irradiation group (OR=3.727, P=0.007). However, the rates of ≥grades 3 acute radiation pneumonitis and esophagitis were significantly higher in the elective nodal irradiation group than in the involved-field irradiation group (OR=0.348, P=0.001, OR=0.385, P=0.000). 1-, 2-, 3-year local control rates (OR=0.966, P=0.837, OR=0.946, P=0.781; OR=0.732P=0.098) and 1-, 3-, 5-year survival rates were similar in the two groups ( OR=0.966, P=0.837; OR=0.946, P=0.781; OR=0.732, P=0.098; OR=0.952, P=0.756; OR=1.149, P=0.422; OR=0.768, P=0.120). It is the same with the rates of distant metastasis (OR=0.986, P=0.937). Conclusion: Compared with involved-field irradiation, the elective nodal irradiation can reduce the rates of out-field failure for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. However, its advantage of local control and survival rates is not obvious and it increases the incidence

Conformal radiotherapy with intensity modulation and integrated boost in the head and neck cancers: experience of the Curie Institute

International Nuclear Information System (INIS)

Toledano, I.; Serre, A.; Bensadoun, R.J.; Ortholan, C.; Racadot, S.; Calais, G.; Alfonsi, M.; Giraud, P.; Graff, P.; Serre, A.; Bensadoun, R.J.; Ortholan, C.; Racadot, S.; Calais, G.; Alfonsi, M.; Giraud, P.

2009-01-01

The modulated intensity radiotherapy (I.M.R.T.) is used in the treatment of cancers in superior aero digestive tracts to reduce the irradiation of parotids and to reduce the delayed xerostomia. This retrospective study presents the results got on the fourteen first patients according an original technique of I.M.R.T. with integrated boost. It appears that this technique is feasible and allows to reduce the xerostomia rate without modifying the local control rate. To limit the average dose to the parotids under 30 Gy seems reduce the incidence of severe xerostomia. (N.C.)

Intensity-modulated radiotherapy vs. parotid-sparing 3D conformal radiotherapy. Effect on outcome and toxicity in locally advanced head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Lambrecht, M.; Nevens, D.; Nuyts, S. [University Hospitals Leuven (Belgium). Dept. of Radiation Oncology

2013-03-15

Background and purpose: Intensity-modulated radiotherapy (IMRT) has rapidly become standard of care in the management of locally advanced head and neck squamous cell carcinoma (HNSCC). In this study, our aim was to retrospectively investigate the effect of the introducing IMRT on outcome and treatment-related toxicity compared to parotid-sparing 3D conformal radiotherapy (3DCRT). Material and methods: A total of 245 patients with stage III and IV HNSCC treated with primary radiotherapy between January 2003 and December 2010 were included in this analysis: 135 patients were treated with 3DCRT, 110 patients with IMRT. Groups were compared for acute and late toxicity, locoregional control (LRC), and overall survival (OS). Oncologic outcomes were estimated using Kaplan-Meier analysis and compared using a log-rank test. Acute toxicity was analyzed according to the Common Terminology Criteria for Adverse Events v3.0 and late toxicity was scored using the RTOG/EORTC late toxicity scoring system. Results: Median follow-up was 35 months in the IMRT group and 68 months in the 3DCRT group. No significant differences were found in 3-year LRC and OS rates between the IMRT group and 3DCRT group. Significantly less acute mucositis {>=} grade 3 was observed in the IMRT group (32% vs. 44%, p = 0.03). There was significantly less late xerostomia {>=} grade 2 in the IMRT group than in the 3DCRT group (23% vs. 68%, p < 0.001). After 24 months, there was less dysphagia {>=} grade 2 in the IMRT group although differences failed to reach statistical significance. Conclusion: The introduction of IMRT in the radiotherapeutic management of locally advanced head and neck cancer significantly improved late toxicity without compromising tumor control compared to a parotid-sparing 3D conformal radiotherapy technique. (orig.)

Pleural Intensity-Modulated Radiotherapy for Malignant Pleural Mesothelioma

International Nuclear Information System (INIS)

Rosenzweig, Kenneth E.; Zauderer, Marjorie G.; Laser, Benjamin; Krug, Lee M.; Yorke, Ellen; Sima, Camelia S.; Rimner, Andreas; Flores, Raja; Rusch, Valerie

2012-01-01

Purpose: In patients with malignant pleural mesothelioma who are unable to undergo pneumonectomy, it is difficult to deliver tumoricidal radiation doses to the pleura without significant toxicity. We have implemented a technique of using intensity-modulated radiotherapy (IMRT) to treat these patients, and we report the feasibility and toxicity of this approach. Methods and Materials: Between 2005 and 2010, 36 patients with malignant pleural mesothelioma and two intact lungs (i.e., no previous pneumonectomy) were treated with pleural IMRT to the hemithorax (median dose, 46.8 Gy; range, 41.4–50.4) at Memorial Sloan-Kettering Cancer Center. Results: Of the 36 patients, 56% had right-sided tumors. The histologic type was epithelial in 78%, sarcomatoid in 6%, and mixed in 17%, and 6% had Stage I, 28% had Stage II, 33% had Stage III, and 33% had Stage IV. Thirty-two patients (89%) received induction chemotherapy (mostly cisplatin and pemetrexed); 56% underwent pleurectomy/decortication before IMRT and 44% did not undergo resection. Of the 36 patients evaluable for acute toxicity, 7 (20%) had Grade 3 or worse pneumonitis (including 1 death) and 2 had Grade 3 fatigue. In 30 patients assessable for late toxicity, 5 had continuing Grade 3 pneumonitis. For patients treated with surgery, the 1- and 2-year survival rate was 75% and 53%, and the median survival was 26 months. For patients who did not undergo surgical resection, the 1- and 2-year survival rate was 69% and 28%, and the median survival was 17 months. Conclusions: Treating the intact lung with pleural IMRT in patients with malignant pleural mesothelioma is a safe and feasible treatment option with an acceptable rate of pneumonitis. Additionally, the survival rates were encouraging in our retrospective series, particularly for the patients who underwent pleurectomy/decortication. We have initiated a Phase II trial of induction chemotherapy with pemetrexed and cisplatin with or without pleurectomy

Pleural Intensity-Modulated Radiotherapy for Malignant Pleural Mesothelioma

Energy Technology Data Exchange (ETDEWEB)

Rosenzweig, Kenneth E., E-mail: ken.rosenzweig@mountsinai.org [Department of Radiation Oncology, Mount Sinai Medical Center, New York, NY (United States); Zauderer, Marjorie G. [Department of Medicine, Thoracic Oncology Service, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Laser, Benjamin [Department of Radiation Oncology, Henry Ford Hospital, Detroit, MI (United States); Krug, Lee M. [Department of Medicine, Thoracic Oncology Service, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yorke, Ellen [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Sima, Camelia S. [Department of Epidemiology/Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Rimner, Andreas [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Flores, Raja [Department of Surgery, Mount Sinai Medical Center, New York, NY (United States); Rusch, Valerie [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-07-15

Purpose: In patients with malignant pleural mesothelioma who are unable to undergo pneumonectomy, it is difficult to deliver tumoricidal radiation doses to the pleura without significant toxicity. We have implemented a technique of using intensity-modulated radiotherapy (IMRT) to treat these patients, and we report the feasibility and toxicity of this approach. Methods and Materials: Between 2005 and 2010, 36 patients with malignant pleural mesothelioma and two intact lungs (i.e., no previous pneumonectomy) were treated with pleural IMRT to the hemithorax (median dose, 46.8 Gy; range, 41.4-50.4) at Memorial Sloan-Kettering Cancer Center. Results: Of the 36 patients, 56% had right-sided tumors. The histologic type was epithelial in 78%, sarcomatoid in 6%, and mixed in 17%, and 6% had Stage I, 28% had Stage II, 33% had Stage III, and 33% had Stage IV. Thirty-two patients (89%) received induction chemotherapy (mostly cisplatin and pemetrexed); 56% underwent pleurectomy/decortication before IMRT and 44% did not undergo resection. Of the 36 patients evaluable for acute toxicity, 7 (20%) had Grade 3 or worse pneumonitis (including 1 death) and 2 had Grade 3 fatigue. In 30 patients assessable for late toxicity, 5 had continuing Grade 3 pneumonitis. For patients treated with surgery, the 1- and 2-year survival rate was 75% and 53%, and the median survival was 26 months. For patients who did not undergo surgical resection, the 1- and 2-year survival rate was 69% and 28%, and the median survival was 17 months. Conclusions: Treating the intact lung with pleural IMRT in patients with malignant pleural mesothelioma is a safe and feasible treatment option with an acceptable rate of pneumonitis. Additionally, the survival rates were encouraging in our retrospective series, particularly for the patients who underwent pleurectomy/decortication. We have initiated a Phase II trial of induction chemotherapy with pemetrexed and cisplatin with or without pleurectomy

Comparison of Toxicity Between Intensity-Modulated Radiotherapy and 3-Dimensional Conformal Radiotherapy for Locally Advanced Non-small-cell Lung Cancer.

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Ling, Diane C; Hess, Clayton B; Chen, Allen M; Daly, Megan E

2016-01-01

The role of intensity-modulated radiotherapy (IMRT) in reducing treatment-related toxicity for locally advanced non-small-cell lung cancer (NSCLC) remains incompletely defined. We compared acute toxicity and oncologic outcomes in a large cohort of patients treated with IMRT or 3-dimensional conformal radiotherapy (3-DCRT), with or without elective nodal irradiation (ENI). A single-institution retrospective review was performed evaluating 145 consecutive patients with histologically confirmed stage III NSCLC treated with definitive chemoradiotherapy. Sixty-five (44.8%) were treated with 3-DCRT using ENI, 43 (30.0%) with 3-DCRT using involved-field radiotherapy (IFRT), and 37 (25.5%) with IMRT using IFRT. All patients received concurrent chemotherapy. Comparison of acute toxicities by treatment technique (IMRT vs. 3-DCRT) and extent of nodal irradiation (3-DCRT-IFRT vs. 3-DCRT-ENI) was performed for grade 2 or higher esophagitis or pneumonitis, number of acute hospitalizations, incidence of opioid requirement, percutaneous endoscopic gastrostomy utilization, and percentage weight loss during treatment. Local control and overall survival were analyzed by the Kaplan-Meier method. We identified no significant differences in any measures of acute toxicity by treatment technique or extent of nodal irradiation. There was a trend toward lower rates of grade 2 or higher pneumonitis among IMRT patients compared to 3-DCRT patients (5.4% vs. 23.0%; P = .065). Local control and overall survival were similar between cohorts. Acute and subacute toxicities were similar for patients treated with IMRT and with 3-DCRT with or without ENI, with a nonsignificant trend toward a reduction in pneumonitis with IMRT. Larger studies are needed to better define which patients will benefit from IMRT. Copyright © 2016 Elsevier Inc. All rights reserved.

Integral test phantom for dosimetric quality assurance of image guided and intensity modulated stereotactic radiotherapy.

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Létourneau, Daniel; Keller, Harald; Sharpe, Michael B; Jaffray, David A

2007-05-01

The objective of this work is to develop a dosimetric phantom quality assurance (QA) of linear accelerators capable of cone-beam CT (CBCT) image guided and intensity-modulated radiotherapy (IG-IMRT). This phantom is to be used in an integral test to quantify in real-time both the performance of the image guidance and the dose delivery systems in terms of dose localization. The prototype IG-IMRT QA phantom consisted of a cylindrical imaging phantom (CatPhan) combined with an array of 11 radiation diodes mounted on a 10 cm diameter disk, oriented perpendicular to the phantom axis. Basic diode response characterization was performed for 6 and 18 MV photons. The diode response was compared to planning system calculations in the open and penumbrae regions of simple and complex beam arrangements. The clinical use of the QA phantom was illustrated in an integral test of an IG-IMRT treatment designed for a clinical spinal radiosurgery case. The sensitivity of the phantom to multileaf collimator (MLC) calibration and setup errors in the clinical setting was assessed by introducing errors in the IMRT plan or by displacing the phantom. The diodes offered good response linearity and long-term reproducibility for both 6 and 18 MV. Axial dosimetry of coplanar beams (in a plane containing the beam axes) was made possible with the nearly isoplanatic response of the diodes over 360 degrees of gantry (usually within +/-1%). For single beam geometry, errors in phantom placement as small as 0.5 mm could be accurately detected (in gradient > or = 1% /mm). In clinical setting, MLC systematic errors of 1 mm on a single MLC bank introduced in the IMRT plan were easily detectable with the QA phantom. The QA phantom demonstrated also sufficient sensitivity for the detection of setup errors as small as 1 mm for the IMRT delivery. These results demonstrated that the prototype can accurately and efficiently verify the entire IG-IMRT process. This tool, in conjunction with image guidance

Integral test phantom for dosimetric quality assurance of image guided and intensity modulated stereotactic radiotherapy

International Nuclear Information System (INIS)

Letourneau, Daniel; Keller, Harald; Sharpe, Michael B.; Jaffray, David A.

2007-01-01

The objective of this work is to develop a dosimetric phantom quality assurance (QA) of linear accelerators capable of cone-beam CT (CBCT) image guided and intensity-modulated radiotherapy (IG-IMRT). This phantom is to be used in an integral test to quantify in real-time both the performance of the image guidance and the dose delivery systems in terms of dose localization. The prototype IG-IMRT QA phantom consisted of a cylindrical imaging phantom (CatPhan) combined with an array of 11 radiation diodes mounted on a 10 cm diameter disk, oriented perpendicular to the phantom axis. Basic diode response characterization was performed for 6 and 18 MV photons. The diode response was compared to planning system calculations in the open and penumbrae regions of simple and complex beam arrangements. The clinical use of the QA phantom was illustrated in an integral test of an IG-IMRT treatment designed for a clinical spinal radiosurgery case. The sensitivity of the phantom to multileaf collimator (MLC) calibration and setup errors in the clinical setting was assessed by introducing errors in the IMRT plan or by displacing the phantom. The diodes offered good response linearity and long-term reproducibility for both 6 and 18 MV. Axial dosimetry of coplanar beams (in a plane containing the beam axes) was made possible with the nearly isoplanatic response of the diodes over 360 deg. of gantry (usually within ±1%). For single beam geometry, errors in phantom placement as small as 0.5 mm could be accurately detected (in gradient ≥1%/mm). In clinical setting, MLC systematic errors of 1 mm on a single MLC bank introduced in the IMRT plan were easily detectable with the QA phantom. The QA phantom demonstrated also sufficient sensitivity for the detection of setup errors as small as 1 mm for the IMRT delivery. These results demonstrated that the prototype can accurately and efficiently verify the entire IG-IMRT process. This tool, in conjunction with image guidance capabilities

Image-guided intensity modulated radiotherapy with helical tomotherapy for postoperative treatment of high-risk oral cavity cancer

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Hsieh, Chen-Hsi; Hsieh, Yen-Ping; Lin, Shoei Long; Chen, Chun-Yi; Chen, Chien-An; Shueng, Pei-Wei; Kuo, Ying-Shiung; Liao, Li-Jen; Hu, Kawang-Yu; Lin, Shih-Chiang; Wu, Le-Jung; Lin, Yu-Chin; Chen, Yu-Jen; Wang, Li-Ying

2011-01-01

The aim of this study was to assess the treatment results and toxicity profiles of helical tomotherapy (HT) for postoperative high-risk oral cavity cancer. From December 6, 2006 through October 9, 2009, 19 postoperative high-risk oral cavity cancer patients were enrolled. All of the patients received HT with (84%) or without (16%) chemotherapy. The median follow-up time was 17 months. The 2-year overall survival, disease-free survival, locoregional control, and distant metastasis-free rates were 94%, 84%, 92%, and 94%, respectively. The package of overall treatment time > 13 wk, the interval between surgery and radiation ≤ 6 wk, and the overall treatment time of radiation ≤ 7 wk was 21%, 84%, and 79%, respectively. The percentage of grade 3 mucositis, dermatitis, and leucopenia was 42%, 5% and 5%, respectively. HT achieved encouraging clinical outcomes for postoperative high-risk oral cavity cancer patients with high compliance. A long-term follow-up study is needed to confirm these preliminary findings

Volumetric Modulated Arc Therapy for Spine Radiosurgery: Superior Treatment Planning and Delivery Compared to Static Beam Intensity Modulated Radiotherapy.

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Zach, Leor; Tsvang, Lev; Alezra, Dror; Ben Ayun, Maoz; Harel, Ran

2016-01-01

Spine stereotactic radiosurgery (SRS) delivers an accurate and efficient high radiation dose to vertebral metastases in 1-5 fractions. We aimed to compare volumetric modulated arc therapy (VMAT) to static beam intensity modulated radiotherapy (IMRT) for spine SRS. Ten spine lesions of previously treated SRS patients were planned retrospectively using both IMRT and VMAT with a prescribed dose of 16 Gy to 100% of the planning target volume (PTV). The plans were compared for conformity, homogeneity, treatment delivery time, and safety (spinal cord dose). All evaluated parameters favored the VMAT plan over the IMRT plans. D min in the IMRT was significantly lower than in the VMAT plan (7.65 Gy/10.88 Gy, p DSC) was found to be significantly better for the VMAT plans compared to the IMRT plans (0.77/0.58, resp., p  value < 0.01), and an almost 50% reduction in the net treatment time was calculated for the VMAT compared to the IMRT plans (6.73 min/12.96 min, p < 0.001). In our report, VMAT provides better conformity, homogeneity, and safety profile. The shorter treatment time is a major advantage and not only provides convenience to the painful patient but also contributes to the precision of this high dose radiation therapy.

Intensity-Modulated Radiotherapy Triggers Onset of Bullous Pemphigoid in a Patient with Advanced Melanoma Treated with Nivolumab

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Kayo Tanita

2018-02-01

Full Text Available Since the efficacy of ipilimumab on nivolumab-resistant advanced melanoma is extremely low, additional supportive therapy for anti-PD-1 antibody therapy-resistant advanced melanoma is needed. Although several supportive therapies that enhance the antitumor immune response of anti-PD-1 antibodies have already been reported, unexpected immune-related adverse events were detected at the same time. In this report, we describe a patient with advanced melanoma treated with nivolumab followed by intensity-modulated radiotherapy, which might have triggered bullous pemphigoid (BP. Although several cases of BP developing in anti-PD-1 antibody-treated patients have already been reported, in this report, we shed light on the possible pathogenesis of BP developing in a patient treated with nivolumab through M2 macrophages.

MRI-detected skull-base invasion. Prognostic value and therapeutic implication in intensity-modulated radiotherapy treatment for nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Cheng, Yi-Kan; Jiang, Ning; Yue, Dan; Tang, Ling-Long; Zhang, Fan; Lin, Li; Liu, Xu; Chen, Lei; Ma, Jun; Liu, Li-Zhi

2014-01-01

With advances in imaging and radiotherapy, the prognostic value of skull-base invasion in nasopharyngeal carcinoma (NPC) needs to be reassessed. We aimed to define a classification system and evaluate the prognostic value of the classification of magnetic resonance imaging (MRI)-detected skull-base invasion in NPC treated with intensity-modulated radiotherapy (IMRT). We retrospectively reviewed 749 patients who underwent MRI and were subsequently histologically diagnosed with nondisseminated NPC and treated with IMRT. MRI-detected skull-base invasion was not found to be an independent prognostic factor for overall survival (OS), distant metastasis-free survival (DMFS), local relapse-free survival (LRFS), or disease-free survival (DFS; p > 0.05 for all). Skull-base invasion was classified according to the incidence of each site (type I sites inside pharyngobasilar fascia and clivus vs. type II sites outside pharyngobasilar fascia). The 5-year OS, DMFS, LRFS, and DFS rates in the classification of skull-base invasion in NPC were 83 vs. 67 %, 85 vs.75 %, 95 vs. 88 %, and 76 vs. 62 %, respectively (p [de

Postoperative radiotherapy for rectal and rectosigmoid cancer

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Aleman, B.M.P.; Lebesque, J.V.; Hart, A.A.M.

1992-01-01

Between 1984 and 1988, 206 patients were treated with pelvic radiotherapy after macroscopically complete surgery for rectal or (recto)sigmoid cancer. Depending on an estimation of the amount of small bowel in the intended treatment volume a total dose was, in general, 45 or 50 Gy. An additional boost of 10 Gy was given to 6 patients because of microscopically involved surgical margins. For tumor stage B a statistically significant trend (p=0.017) for higher local control with higher total dose was observed comparing patients treated with a total dose of 45 Gy or less, with more than 45 Gy but less than 50 Gy or with a total dose of 50 Gy or more. This finding illustrates the impact of total dose on local control for postoperative radiotherapy for rectal carcinoma. (author). 18 refs., 1 fig., 1 tab

Individualized planning target volumes for intrafraction motion during hypofractionated intensity-modulated radiotherapy boost for prostate cancer

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Cheung, Patrick; Sixel, Katharina; Morton, Gerard; Loblaw, D. Andrew; Tirona, Romeo; Pang, Geordi; Choo, Richard; Szumacher, Ewa; DeBoer, Gerrit; Pignol, Jean-Philippe

2005-01-01

Purpose: The objective of the study was to access toxicities of delivering a hypofractionated intensity-modulated radiotherapy (IMRT) boost with individualized intrafraction planning target volume (PTV) margins and daily online correction for prostate position. Methods and materials: Phase I involved delivering 42 Gy in 21 fractions using three-dimensional conformal radiotherapy, followed by a Phase II IMRT boost of 30 Gy in 10 fractions. Digital fluoroscopy was used to measure respiratory-induced motion of implanted fiducial markers within the prostate. Electronic portal images were taken of fiducial marker positions before and after each fraction of radiotherapy during the first 9 days of treatment to calculate intrafraction motion. A uniform 10-mm PTV margin was used for the first phase of treatment. PTV margins for Phase II were patient-specific and were calculated from the respiratory and intrafraction motion data obtained from Phase I. The IMRT boost was delivered with daily online correction of fiducial marker position. Acute toxicity was measured using National Cancer Institute Common Toxicity Criteria, version 2.0. Results: In 33 patients who had completed treatment, the average PTV margin used during the hypofractionated IMRT boost was 3 mm in the lateral direction, 3 mm in the superior-inferior direction, and 4 mm in the anteroposterior direction. No patients developed acute Grade 3 rectal toxicity. Three patients developed acute Grade 3 urinary frequency and urgency. Conclusions: PTV margins can be reduced significantly with daily online correction of prostate position. Delivering a hypofractionated boost with this high-precision IMRT technique resulted in acceptable acute toxicity

Intensity modulated radiotherapy with simultaneous integrated boost vs. conventional radiotherapy with sequential boost for breast cancer - A preliminary result.

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Lee, Hsin-Hua; Hou, Ming-Feng; Chuang, Hung-Yi; Huang, Ming-Yii; Tsuei, Le-Ping; Chen, Fang-Ming; Ou-Yang, Fu; Huang, Chih-Jen

2015-10-01

This study was aimed to assess the acute dermatological adverse effect from two distinct RT techniques for breast cancer patients. We compared intensity-modulated radiotherapy with simultaneous integrated boost (IMRT-SIB) and conventional radiotherapy followed by sequential boost (CRT-SB). The study population was composed of 126 consecutive female breast cancer patients treated with breast conserving surgery. Sixty-six patients received IMRT-SIB to 2 dose levels simultaneously. They received 50.4 Gy at 1.8 Gy per fraction to the whole breast and 60.2 Gy at 2.15 Gy per fraction to the tumor bed by integral boost. Sixty patients in the CRT-SB group received 50 Gy in 25 fractions to the whole breast followed by a boost irradiation to tumor bed in 5-7 fractions to a total dose of 60-64 Gy. Acute skin toxicities were documented in agreement with the Common Terminology Criteria for Adverse Events version 3 (CTCAE v.3.0). Ninety-eight patients had grade 1 radiation dermatitis while 14 patients had grade 2. Among those with grade 2, there were 3 patients in IMRT-SIB group (4.5%) while 11 in CRT-SB group (18.3%). (P = 0.048) There was no patient with higher than grade 2 toxicity. Three year local control was 99.2%, 3-year disease free survival was 97.5% and 3-year overall survival was 99.2%. A significant reduction in the severity of acute radiation dermatitis from IMRT-SIB comparing with CRT-SB is demonstrated. Copyright © 2015 Elsevier Ltd. All rights reserved.

Classical prognostic factors in patients with non-advanced endometrial cancer treated with postoperative radiotherapy

International Nuclear Information System (INIS)

Karolewski, K.; Kojs, Z.; Jakubowicz, J.; Urbanski, K.; Michalak, A.

2006-01-01

Aim: Analysis of classical prognostic factors in patients with non-advanced endometrial cancer treated with postoperative radiotherapy. Materials/Methods: In the years 1985 - 1999, 705 patients underwent postoperative radiotherapy due to endometrial cancer: 529 patients with FIGO stage I and 176 with FIGO stage II cancer. Mean age was 58 years. In 96% of patients endometrioid adenocarcinoma was found. In 49.9% the cancer had a high, in 27.9% a medium, and in 22.2% a low degree of differentiation. Results: 82% of patients had 5-year disease-free survival. In univariate analysis a significantly higher rate of disease-free survival was observed in: patients younger than 60, with moderately and well differentiated cancers, with stage I endometrioid adenocarcinoma with less than 50% myometrial invasion. In multivariate analysis degree of cancer differentiation was the only independent prognostic factor. Conclusions: In a group of patients with non-advanced endometrial cancer treated with postoperative radiotherapy, degree of cancer differentiation is the primary prognostic factor. (authors)

Random and systematic beam modulator errors in dynamic intensity modulated radiotherapy

International Nuclear Information System (INIS)

Parsai, Homayon; Cho, Paul S; Phillips, Mark H; Giansiracusa, Robert S; Axen, David

2003-01-01

This paper reports on the dosimetric effects of random and systematic modulator errors in delivery of dynamic intensity modulated beams. A sliding-widow type delivery that utilizes a combination of multileaf collimators (MLCs) and backup diaphragms was examined. Gaussian functions with standard deviations ranging from 0.5 to 1.5 mm were used to simulate random positioning errors. A clinical example involving a clival meningioma was chosen with optic chiasm and brain stem as limiting critical structures in the vicinity of the tumour. Dose calculations for different modulator fluctuations were performed, and a quantitative analysis was carried out based on cumulative and differential dose volume histograms for the gross target volume and surrounding critical structures. The study indicated that random modulator errors have a strong tendency to reduce minimum target dose and homogeneity. Furthermore, it was shown that random perturbation of both MLCs and backup diaphragms in the order of σ = 1 mm can lead to 5% errors in prescribed dose. In comparison, when MLCs or backup diaphragms alone was perturbed, the system was more robust and modulator errors of at least σ = 1.5 mm were required to cause dose discrepancies greater than 5%. For systematic perturbation, even errors in the order of ±0.5 mm were shown to result in significant dosimetric deviations

Postoperative craniospinal radiotherapy of medulloblastoma in children and young adults

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Golubičić Ivana V.

2003-01-01

Full Text Available PURPOSE The aim of this study was: 1. to evaluate treatment results of combined therapy (surgery, postoperative craniospinal radiotherapy with or without chemotherapy and 2. to assess factors affecting prognosis (extend of tumor removal, involvement of the brain stem, extent of disease postoperative meningitis, shunt placement, age, sex and time interval from surgery to start of postoperative radiotherapy. PATIENTS AND METHODS During the period 1986-1996, 78 patients with medulloblastoma, aged 1-22 years (median 8.6 years, were treated with combined modality therapy and 72 of them were evaluable for the study end-points. Entry criteria were histologically proven diagnosis, age under 22 years, and no history of previous malignant disease. The main characteristics of the group are shown in Table 1. Twenty-nine patients (37.2% have total, 8 (10.3% near total and 41 (52.5% partial removal. Seventy-two of 78 patients were treated with curative intent and received postoperative craniospinal irradiation. Radiotherapy started 13-285 days after surgery (median 36 days. Only 13 patients started radiotherapy after 60 days following surgery. Adjuvant chemotherapy was applied in 63 (80.7% patients. The majority of them (46 73% received chemotherapy with CCNU and Vincristine. The survival rates were calculated with the Kaplan-Meier method and the differences in survival were analyzed using the Wilcoxon test and log-rank test. RESULTS The follow-up period ranged from 1-12 years (median 3 years. Five-year overall survival (OS was 51% and disease-free survival (DFS 47% (Graph 1. During follow-up 32 relapses occurred. Patients having no brain stem infiltration had significantly better survival (p=0.0023 (Graph 2. Patients with positive myelographic findings had significantly poorer survival compared to dose with negative myelographic findings (p=0.0116. Significantly poorer survival was found in patients with meningitis developing in the postoperative period

Image-guided intensity modulated radiotherapy with helical tomotherapy for postoperative treatment of high-risk oral cavity cancer

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Chen Yu-Jen

2011-01-01

Full Text Available Abstract Background The aim of this study was to assess the treatment results and toxicity profiles of helical tomotherapy (HT for postoperative high-risk oral cavity cancer. Methods From December 6, 2006 through October 9, 2009, 19 postoperative high-risk oral cavity cancer patients were enrolled. All of the patients received HT with (84% or without (16% chemotherapy. Results The median follow-up time was 17 months. The 2-year overall survival, disease-free survival, locoregional control, and distant metastasis-free rates were 94%, 84%, 92%, and 94%, respectively. The package of overall treatment time > 13 wk, the interval between surgery and radiation ≤ 6 wk, and the overall treatment time of radiation ≤ 7 wk was 21%, 84%, and 79%, respectively. The percentage of grade 3 mucositis, dermatitis, and leucopenia was 42%, 5% and 5%, respectively. Conclusions HT achieved encouraging clinical outcomes for postoperative high-risk oral cavity cancer patients with high compliance. A long-term follow-up study is needed to confirm these preliminary findings.

Decreasing Temporal Lobe Dose With Five-Field Intensity-Modulated Radiotherapy for Treatment of Pituitary Macroadenomas

International Nuclear Information System (INIS)

Parhar, Preeti K.; Duckworth, Tamara; Shah, Parinda; DeWyngaert, J. Keith; Narayana, Ashwatha; Formenti, Silvia C.; Shah, Jinesh N.

2010-01-01

Purpose: To compare temporal lobe dose delivered by three pituitary macroadenoma irradiation techniques: three-field three-dimensional conformal radiotherapy (3D-CRT), three-field intensity-modulated radiotherapy (3F IMRT), and a proposed novel alternative of five-field IMRT (5F IMRT). Methods and Materials: Computed tomography-based external beam radiotherapy planning was performed for 15 pituitary macroadenoma patients treated at New York University between 2002 and 2007 using: 3D-CRT (two lateral, one midline superior anterior oblique [SAO] beams), 3F IMRT (same beam angles), and 5F IMRT (same beam angles with additional right SAO and left SAO beams). Prescription dose was 45 Gy. Target volumes were: gross tumor volume (GTV) = macroadenoma, clinical target volume (CTV) = GTV, and planning target volume = CTV + 0.5 cm. Structure contouring was performed by two radiation oncologists guided by an expert neuroradiologist. Results: Five-field IMRT yielded significantly decreased temporal lobe dose delivery compared with 3D-CRT and 3F IMRT. Temporal lobe sparing with 5F IMRT was most pronounced at intermediate doses: mean V25Gy (% of total temporal lobe volume receiving ≥25 Gy) of 13% vs. 28% vs. 29% for right temporal lobe and 14% vs. 29% vs. 30% for left temporal lobe for 5F IMRT, 3D-CRT, and 3F IMRT, respectively (p -7 for 5F IMRT vs. 3D-CRT and 5F IMRT vs. 3F IMRT). Five-field IMRT plans did not compromise target coverage, exceed normal tissue dose constraints, or increase estimated brain integral dose. Conclusions: Five-field IMRT irradiation technique results in a statistically significant decrease in the dose to the temporal lobes and may thus help prevent neurocognitive sequelae in irradiated pituitary macroadenoma patients.

Intensity-Modulated Radiotherapy in the Treatment of Oropharyngeal Cancer: An Update of the Memorial Sloan-Kettering Cancer Center Experience

International Nuclear Information System (INIS)

Setton, Jeremy; Caria, Nicola; Romanyshyn, Jonathan; Koutcher, Lawrence; Wolden, Suzanne L.; Zelefsky, Michael J.; Rowan, Nicholas; Sherman, Eric J.; Fury, Matthew G.; Pfister, David G.; Wong, Richard J.; Shah, Jatin P.; Kraus, Dennis H.; Shi Weiji; Zhang Zhigang; Schupak, Karen D.; Gelblum, Daphna Y.; Rao, Shyam D.; Lee, Nancy Y.

2012-01-01

Purpose: To update the Memorial Sloan-Kettering Cancer Center’s experience with intensity-modulated radiotherapy (IMRT) in the treatment of oropharyngeal cancer (OPC). Methods and Materials: Between September 1998 and April 2009, 442 patients with histologically confirmed OPC underwent IMRT at our center. There were 379 men and 63 women with a median age of 57 years (range, 27–91). The disease was Stage I in 2%, Stage II in 4%, Stage III in 21%, and Stage IV in 73% of patients. The primary tumor subsite was tonsil in 50%, base of tongue in 46%, pharyngeal wall in 3%, and soft palate in 2%. The median prescription dose to the planning target volume of the gross tumor was 70 Gy for definitive (n = 412) cases and 66 Gy for postoperative cases (n = 30). A total 404 patients (91%) received chemotherapy, including 389 (88%) who received concurrent chemotherapy, the majority of which was platinum-based. Results: Median follow-up among surviving patients was 36.8 months (range, 3–135). The 3-year cumulative incidence of local failure, regional failure, and distant metastasis was 5.4%, 5.6%, and 12.5%, respectively. The 3-year OS rate was 84.9%. The incidence of late dysphagia and late xerostomia ≥Grade 2 was 11% and 29%, respectively. Conclusions: Our results confirm the feasibility of IMRT in achieving excellent locoregional control and low rates of xerostomia. According to our knowledge, this study is the largest report of patients treated with IMRT for OPC.

Intensity-Modulated Radiotherapy in the Treatment of Oropharyngeal Cancer: An Update of the Memorial Sloan-Kettering Cancer Center Experience

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Setton, Jeremy; Caria, Nicola; Romanyshyn, Jonathan; Koutcher, Lawrence; Wolden, Suzanne L.; Zelefsky, Michael J.; Rowan, Nicholas [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Sherman, Eric J.; Fury, Matthew G.; Pfister, David G. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Wong, Richard J.; Shah, Jatin P.; Kraus, Dennis H. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Shi Weiji; Zhang Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Schupak, Karen D.; Gelblum, Daphna Y.; Rao, Shyam D. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Lee, Nancy Y., E-mail: Leen2@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-01-01

Purpose: To update the Memorial Sloan-Kettering Cancer Center's experience with intensity-modulated radiotherapy (IMRT) in the treatment of oropharyngeal cancer (OPC). Methods and Materials: Between September 1998 and April 2009, 442 patients with histologically confirmed OPC underwent IMRT at our center. There were 379 men and 63 women with a median age of 57 years (range, 27-91). The disease was Stage I in 2%, Stage II in 4%, Stage III in 21%, and Stage IV in 73% of patients. The primary tumor subsite was tonsil in 50%, base of tongue in 46%, pharyngeal wall in 3%, and soft palate in 2%. The median prescription dose to the planning target volume of the gross tumor was 70 Gy for definitive (n = 412) cases and 66 Gy for postoperative cases (n = 30). A total 404 patients (91%) received chemotherapy, including 389 (88%) who received concurrent chemotherapy, the majority of which was platinum-based. Results: Median follow-up among surviving patients was 36.8 months (range, 3-135). The 3-year cumulative incidence of local failure, regional failure, and distant metastasis was 5.4%, 5.6%, and 12.5%, respectively. The 3-year OS rate was 84.9%. The incidence of late dysphagia and late xerostomia {>=}Grade 2 was 11% and 29%, respectively. Conclusions: Our results confirm the feasibility of IMRT in achieving excellent locoregional control and low rates of xerostomia. According to our knowledge, this study is the largest report of patients treated with IMRT for OPC.

Postoperative interstitial radiotherapy of keloids

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Clavere, P.; Bonnafoux-Clavere, A.; Roullet, B.; Morzel, A.; Rhein, B.; Bonnetblanc, J.M.; Olivier, J.P.

1993-01-01

During an 8-year period, 21 patients with keloids (27 keloids) were treated with keloidectomy and post-operative interstitial radiotherapy by an iridium 192 wire. Only one patient had been previously treated by corticoids, without results. A dose of 12 Gy (three patients) to 15 Gy (18 patients) was delivered at a point 2.5 mm from the axis of the wire. The follow-up time was from 2 - 104 months. The success rate, at 7 months, was close to 88%. Ao recurrence occurred in three patients without relation to the method used, the lesion-age or the localization of the lesions. There were no side-effects. This method represents an effective, non-constraining and safe treatment for keloids if the contra-indications are respected

Conformal intensity-modulated radiotherapy (IMRT) delivered by robotic linac-conformality versus efficiency of dose delivery

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Webb, Steve

2000-01-01

Intensity-modulated radiotherapy (IMRT) may be delivered with a high-energy-photon linac mounted on a robotic gantry and executing a complex trajectory. In a previous paper an inverse-planning technique was developed for such an application. Here the work is extended to demonstrate the dependence of conformality on the size of the elemental pencil beam, on the complexity of the trajectory and on the sampling of azimuth and elevation of the collimated source. The improved conformality of complex trajectories is demonstrated and benchmarked relative to simpler trajectories, more representative of existing non-robotic IMRT techniques. Specifically, by choosing a very fine pencil beam, exquisitely conformal dose distributions have been obtained. Important sampling considerations have been determined. Expressions have been derived for the dosimetry and monitor-unit efficiency of robotic IMRT. Equivalent trajectories were computed for executing the complex robotic trajectories instead by using a conventional linac. The work benchmarks an ideal in IMRT against which more practical and more common techniques may be measured. (author)

Postoperative adjuvant MVP Chemotherapy and Radiotherapy for Non-Small Cell Lung Cancer

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Kim, Jong Hoon; Choi, Eun Kyung; Chang, Hye Sook

1995-01-01

Purpose : Since February 1991, a prospective study for non-small cell lung cancer patients who underwent radical resection and had a risk factor of positive resection margin or regional lymph node metastasis has been conducted to evaluated the effect of MVP chemotherapy and radiotherapy on the pattern of failure, disease free and overall survival, and tolerance of combined treatment. Materials and Methods : Twenty nine patients were registered to this study until Sep. 1993 ; of these 26 received planned therapy. Within 3 weeks after radical resection, two cycles of MVP(Motomycin C 6 mg/m 2 , Vinblastin 6 mg/m 2 , Cisplatin 6 mg/m 2 ) chemotherapy was given with 4 weeks intervals. Radiotherapy (5040 cGy tumor bed dose and 900 cGy boost to high risk area) was started 3 to 4 weeks after chemotherapy. Results : One and two year overall survival rates were 76.5% and 8.6% respectively. Locoregional failure developed in 6 patients (23.1%) and distant failure in 9 patients(34.6%). Number of involved lymph nodes, resection margin positivity showed some correlation with failure pattern but T-stage and N-stage showed no statistical significance. The group of patients who received chemotherapy within 2 weeks postoperatively and radiotherapy within 70 days showed lower incidence of distant metastasis. Postoperative combined therapy were well tolerated without definite increase of complication rate, and compliance rate in this study was 90%. Conclusion : 1) MVP chemotherapy showed no effect on locoregional recurrence, ut appeared to decrease the distant metastasis rate and 2) combined treatments were well tolerated in all patients. 3) The group of patients who received chemotherapy within 2 weeks postoperatively and radiotherapy within 70 days showed lower incidence of distant metastasis. 4) Addition of chemotherapy to radiotherapy failed to increase the overall or disease free survival

Preliminary results of a phase I/II study of simultaneous modulated accelerated radiotherapy for nondisseminated nasopharyngeal carcinoma

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Lee, Sang-wook; Back, Geum Mun; Yi, Byong Yong; Choi, Eun Kyung; Ahn, Seung Do; Shin, Seong Soo; Kim, Jung-hun; Kim, Sang Yoon; Lee, Bong-Jae; Nam, Soon Yuhl; Choi, Seung-Ho; Kim, Seung-Bae; Park, Jin-hong; Lee, Kang Kyoo; Park, Sung Ho; Kim, Jong Hoon

2006-01-01

Purpose: To present preliminary results of intensity-modulated radiotherapy (IMRT) with the simultaneous modulated accelerated radiotherapy (SMART) boost technique in patients with nasopharyngeal carcinoma (NPC). Methods and Materials: Twenty patients who underwent IMRT for nondisseminated NPC at the Asan Medical Center between September 2001 and December 2003 were prospectively evaluated. Intensity-modulated radiotherapy was delivered with the 'step and shoot' SMART technique at prescribed doses of 72 Gy (2.4 Gy/day) to the gross tumor volume, 60 Gy (2 Gy/day) to the clinical target volume and metastatic nodal station, and 46 Gy (2 Gy/day) to the clinically negative neck region. Eighteen patients also received cisplatin once per week. Results: The median follow-up period was 27 months. Nineteen patients completed the treatment without interruption; the remaining patient interrupted treatment for 2 weeks owing to severe pharyngitis and malnutrition. Five patients (25%) had Radiation Therapy Oncology Group Grade 3 mucositis, whereas 9 (45%) had Grade 3 pharyngitis. Seven patients (35%) lost more than 10% of their pretreatment weight, whereas 11 (55%) required intravenous fluids and/or tube feeding. There was no Grade 3 or 4 xerostomia. All patients showed complete response. Two patients had distant metastases and locoregional recurrence, respectively. Conclusion: Intensity-modulated radiotherapy with the SMART boost technique allows parotid sparing, as shown clinically and by dosimetry, and might also be more effective biologically. A larger population of patients and a longer follow-up period are needed to evaluate ultimate tumor control and late toxicity

Local Control After Intensity-Modulated Radiotherapy for Head-and-Neck Rhabdomyosarcoma

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Curtis, Amarinthia E.; Okcu, M. Fatih; Chintagumpala, Murali; Teh, Bin S.; Paulino, Arnold C.

2009-01-01

Purpose: To examine the patterns of failure in patients treated with intensity-modulated radiotherapy (IMRT) for head-and-neck rhabdomyosarcoma (RMS). Methods and Materials: Between 1998 and 2005, 19 patients with a diagnosis of head-and-neck RMS received IMRT at The Methodist Hospital. There were 11 male and 8 female patients, with a median age of 6 years at time of irradiation. Tumor location was parameningeal in 7, orbital in 6, and other head-and-neck RMS in 6. Chemotherapy was given to all patients, with vincristine, actinomycin D, and cyclophosphamide being the most common regimen (n = 18). The median prescribed dose was 5040 cGy. The clinical target volume included the gross tumor volume with a 1.5-cm margin. The median duration of follow-up for surviving patients was 56 months. Results: The 4-year overall survival and local control rates were 76% and 92.9%, respectively. One patient developed a local failure in the high-dose region of the radiation field; there were no marginal failures. Distant metastasis was seen in 4 patients. Overall survival was 42.9% for parameningeal sites and 100% for other sites (p < 0.01). Late toxicities were seen in 7 patients. Two secondary malignancies occurred in 1 child with embryonal RMS of the face and a p53 mutation. Conclusions: Local control was excellent in patients receiving IMRT for head-and-neck RMS. Patterns of local failure reveal no marginal failures in this group of patients

Local field radiotherapy without elective nodal irradiation for postoperative loco-regional recurrence of esophageal cancer.

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Kimoto, Takuya; Yamazaki, Hideya; Suzuki, Gen; Aibe, Norihiro; Masui, Koji; Tatekawa, Kotoha; Sasaki, Naomi; Fujiwara, Hitoshi; Shiozaki, Atsushi; Konishi, Hirotaka; Nakamura, Satoaki; Yamada, Kei

2017-09-01

Radiotherapy is an effective treatment for the postoperative loco-regional recurrence of esophageal cancer; however, the optimal treatment field remains controversial. This study aims to evaluate the outcome of local field radiotherapy without elective nodal irradiation for postoperative loco-regional recurrence of esophageal cancer. We retrospectively investigated 35 patients treated for a postoperative loco-regional recurrence of esophageal cancer with local field radiotherapy between December 2008 and March 2016. The median irradiation dose was 60 Gy (range: 50-67.5 Gy). Thirty-one (88.6%) patients received concurrent chemotherapy. The median follow-up period was 18 months (range: 5-94 months). The 2-year overall survival was 55.7%, with a median survival time of 29.9 months. In the univariate analysis, the maximal diameter ≤20 mm (P = 0.0383), solitary lesion (P = 0.0352), and the complete remission after treatment (P = 0.00411) had a significantly better prognosis. A total of 27 of 35 patients (77.1%) had progressive disease (loco-regional failure [n = 9], distant metastasis [n = 7], and both loco-regional failure and distant metastasis [n = 11]). No patients had Grade 3 or greater mucositis. Local field radiotherapy is a considerable treatment option for postoperative loco-regional recurrence of esophageal cancer. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Preoperative vs. postoperative radiotherapy in the treatment of soft tissue sarcomas: a matter of presentation

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Pollack, Alan; Zagars, Gunar K.; Goswitz, Mary S.; Pollock, Raphael A.; Feig, Barry W.; Pisters, Peter W.T.

1998-01-01

Purpose: Radiotherapy for soft tissue sarcoma is typically preoperative or postoperative, with advocates of each. In this study, the relationship of the sequencing of radiotherapy and surgery to local control was examined. Methods and Materials: The cohort consisted of 453 patients with Grade 2-3 malignant fibrous histiocytoma, synovial sarcoma, or liposarcoma treated from 1965-1992. Retroperitoneal sarcomas were excluded. Median follow-up was 97 months. There were 3 groups of patients that were classified by the treatment administered at our institution: preoperative radiotherapy to a median dose of 50 Gy given before excision at MDACC (Preop; n = 128); postoperative radiotherapy to a median dose of 64 Gy given after excision at MDACC (Postop; n = 165); and radiotherapy to a median dose of 65 Gy without excision at MDACC (RT Alone; n = 160). Those in the RT Alone Group had gross total excision at an outside center prior to referral. Results: Histological classification, whether locally recurrent at referral, and final MDACC margins were independent determinants of local control in Cox proportional hazards multivariate analysis using the entire cohort. The type of treatment was not significant; however, tumor status at presentation (gross disease vs. excised) affected these findings greatly. Gross disease treated with Preop was controlled locally in 88% at 10 years, as compared to 67% with Postop (p = 0.01). This association was independently significant for patients treated primarily (not for recurrence). In contrast, for those presenting after excision elsewhere, 10-year local control was better with Postop (88% vs. 73%, p = 0.07), particularly for patients treated primarily (91% vs. 72%, p 0.02 in univariate analysis; p = 0.06 in multivariate analysis). Re-excision at MDACC (Postop) resulted in enhanced 10-year local control over that with RT Alone (88% vs. 75%, p = 0.06), and was confirmed to be an independent predictor in multivariate analysis (p = 0

Carotid-Sparing Intensity-Modulated Radiotherapy for Early-Stage Squamous Cell Carcinoma of the True Vocal Cord

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Chera, Bhishamjit S.; Amdur, Robert J.; Morris, Christopher G.; Mendenhall, William M.

2010-01-01

Purpose: To compare radiation doses to carotid arteries among various radiotherapy techniques for treatment of early-stage squamous cell carcinoma (SCC) of the true vocal cords. Methods and Materials: Five patients were simulated using computed tomography (CT). Clinical and planning target volumes (PTV) were created for bilateral and unilateral stage T1 vocal cord cancers. Planning risk volumes for the carotid arteries and spinal cord were delineated. For each patient, three treatment plans were designed for bilateral and unilateral target volumes: opposed laterals (LATS), three-dimensional conformal radiotherapy (3DCRT), and intensity-modulated radiotherapy (IMRT), for a total of 30 plans. More than 95% of the PTV received the prescription dose (63Gy at 2.25 Gy per treatment). Results: Carotid dose was lowest with IMRT. With a bilateral vocal cord target, the median carotid dose was 10Gy with IMRT vs. 25 Gy with 3DCRT and 38 Gy with LATS (p < 0.05); with a unilateral target, the median carotid dose was 4 Gy with IMRT vs. 19 Gy with 3DCRT and 39 Gy with LATS (p < 0.05). The dosimetric tradeoff with IMRT is a small area of high dose in the PTV. The worst heterogeneity results were at a maximum point dose of 80 Gy (127%) in a unilateral target that was close to the carotid. Conclusions: There is no question that IMRT can reduce the dose to the carotid arteries in patients with early-stage vocal cord cancer. The question is whether the potential advantage of reducing the carotid dose outweighs the risk of tumor recurrence due to contouring errors and organ motion and the risk of complications from dose heterogeneity.

Limited benefit of inversely optimised intensity modulation in breast conserving radiotherapy with simultaneously integrated boost

International Nuclear Information System (INIS)

Laan, Hans Paul van der; Dolsma, Wil V.; Schilstra, Cornelis; Korevaar, Erik W.; Bock, Geertruida H. de; Maduro, John H.; Langendijk, Johannes A.

2010-01-01

Background and purpose: To examine whether in breast-conserving radiotherapy (RT) with simultaneously integrated boost (SIB), application of inversely planned intensity-modulated radiotherapy (IMRT-SIB) instead of three-dimensional RT (3D-CRT-SIB) has benefits that justify the additional costs, and to evaluate whether a potential benefit of IMRT-SIB depends on specific patient characteristics. Material and methods: 3D-CRT-SIB and various IMRT-SIB treatment plans were constructed and optimised for 30 patients with early stage left-sided breast cancer. Coverage of planning target volumes (PTVs) and dose delivered to organs at risk (OARs) were determined for each plan. Overlap between heart and breast PTV (OHB), size of breast and boost PTVs and boost location were examined in their ability to identify patients that might benefit from IMRT-SIB. Results: All plans had adequate PTV coverage. IMRT-SIB generally reduced dose levels delivered to heart, lungs, and normal breast tissue relative to 3D-CRT-SIB. However, IMRT-SIB benefit differed per patient. For many patients, comparable results were obtained with 3D-CRT-SIB, while patients with OHB > 1.4 cm and a relatively large boost PTV volume (>125 cm 3 ) gained most from the use of IMRT-SIB. Conclusions: In breast-conserving RT, results obtained with 3D-CRT-SIB and IMRT-SIB are generally comparable. Patient characteristics could be used to identify patients that are most likely to benefit from IMRT-SIB.

Promising results with image guided intensity modulated radiotherapy for muscle invasive bladder cancer

International Nuclear Information System (INIS)

Whalley, D.; Caine, H.; McCloud, P.; Guo, L.; Kneebone, A.; Eade, T.

2015-01-01

To describe the feasibility of image guided intensity modulated radiotherapy (IG-IMRT) using daily soft tissue matching in the treatment of bladder cancer. Twenty-eight patients with muscle-invasive carcinoma of the bladder were recruited to a protocol of definitive radiation using IMRT with accelerated hypofractionation with simultaneous integrated boost (SIB). Isotropic margins of .5 and 1 cm were used to generate the high risk and intermediate risk planning target volumes respectively. Cone beam CT (CBCT) was acquired daily and a soft tissue match was performed. Cystoscopy was scheduled 6 weeks post treatment. The median age was 83 years (range 58-92). Twenty patients had stage II or III disease, and eight were stage IV. Gross disease received 66 Gy in 30 fractions in 11 patients (ten with concurrent chemotherapy) or 55 Gy in 20 fractions for those of poorer performance status or with palliative intent. All patients completed radiation treatment as planned. Three patients ceased chemotherapy early due to toxicity. Six patients (21 %) had acute Grade ≥ 2 genitourinary (GU) toxicity and six (21 %) had acute Grade ≥ 2 gastrointestinal (GI) toxicity. Five patients (18 %) developed Grade ≥2 late GU toxicity and no ≥2 late GI toxicity was observed. Nineteen patients underwent cystoscopy following radiation, with complete response (CR) in 16 cases (86 %), including all patients treated with chemoradiotherapy. Eight patients relapsed, four of which were local relapses. Of the patients with local recurrence, one underwent salvage cystectomy. For patients treated with definitive intent, freedom from locoregional recurrence (FFLR) and overall survival (OS) was 90 %/100 % for chemoradiotherapy versus 86 %/69 % for radiotherapy alone. IG- IMRT using daily soft tissue matching is a feasible in the treatment of bladder cancer, enabling the delivery of accelerated synchronous integrated boost with good early local control outcomes and low toxicity

Volumetric Modulated Arc Therapy for Spine Radiosurgery: Superior Treatment Planning and Delivery Compared to Static Beam Intensity Modulated Radiotherapy

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Leor Zach

2016-01-01

Full Text Available Purpose. Spine stereotactic radiosurgery (SRS delivers an accurate and efficient high radiation dose to vertebral metastases in 1–5 fractions. We aimed to compare volumetric modulated arc therapy (VMAT to static beam intensity modulated radiotherapy (IMRT for spine SRS. Methods and Materials. Ten spine lesions of previously treated SRS patients were planned retrospectively using both IMRT and VMAT with a prescribed dose of 16 Gy to 100% of the planning target volume (PTV. The plans were compared for conformity, homogeneity, treatment delivery time, and safety (spinal cord dose. Results. All evaluated parameters favored the VMAT plan over the IMRT plans. Dmin in the IMRT was significantly lower than in the VMAT plan (7.65 Gy/10.88 Gy, p<0.001, the Dice Similarity Coefficient (DSC was found to be significantly better for the VMAT plans compared to the IMRT plans (0.77/0.58, resp., p  value<0.01, and an almost 50% reduction in the net treatment time was calculated for the VMAT compared to the IMRT plans (6.73 min/12.96 min, p<0.001. Conclusions. In our report, VMAT provides better conformity, homogeneity, and safety profile. The shorter treatment time is a major advantage and not only provides convenience to the painful patient but also contributes to the precision of this high dose radiation therapy.

Salivary Gland Tumors Treated With Adjuvant Intensity-Modulated Radiotherapy With or Without Concurrent Chemotherapy

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Schoenfeld, Jonathan D., E-mail: jdschoenfeld@partners.org [Department of Radiation Oncology, Harvard Radiation Oncology Program, Boston, MA (United States); Sher, David J. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, MA (United States); Norris, Charles M. [Department of Surgery, Division of Otolaryngology, Brigham and Women' s Hospital, Boston, MA (United States); Haddad, Robert I.; Posner, Marshall R. [Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA (United States); Department of Medicine, Brigham and Women' s Hospital, Boston, MA (United States); Balboni, Tracy A.; Tishler, Roy B. [Department of Radiation Oncology, Dana-Farber Cancer Institute and Brigham and Women' s Hospital, Boston, MA (United States)

2012-01-01

Purpose: To analyze the recent single-institution experience of patients with salivary gland tumors who had undergone adjuvant intensity-modulated radiotherapy (IMRT), with or without concurrent chemotherapy. Patients and Methods: We performed a retrospective analysis of 35 salivary gland carcinoma patients treated primarily at the Dana-Farber Cancer Institute between 2005 and 2010 with surgery and adjuvant IMRT. The primary endpoints were local control, progression-free survival, and overall survival. The secondary endpoints were acute and chronic toxicity. The median follow-up was 2.3 years (interquartile range, 1.2-2.8) among the surviving patients. Results: The histologic types included adenoid cystic carcinoma in 15 (43%), mucoepidermoid carcinoma in 6 (17%), adenocarcinoma in 3 (9%), acinic cell carcinoma in 3 (9%), and other in 8 (23%). The primary sites were the parotid gland in 17 (49%), submandibular glands in 6 (17%), tongue in 4 (11%), palate in 4 (11%), and other in 4 (11%). The median radiation dose was 66 Gy, and 22 patients (63%) received CRT. The most common chemotherapy regimen was carboplatin and paclitaxel (n = 14, 64%). A trend was seen for patients undergoing CRT to have more adverse prognostic factors, including Stage T3-T4 disease (CRT, n = 12, 55% vs. n = 4, 31%, p = .29), nodal positivity (CRT, n = 8, 36% vs. n = 1, 8%, p = .10), and positive margins (n = 13, 59% vs. n = 5, 38%, p = .30). One patient who had undergone CRT developed an in-field recurrence, resulting in an overall actuarial 3-year local control rate of 92%. Five patients (14%) developed distant metastases (1 who had undergone IMRT only and 4 who had undergone CRT). Acute Grade 3 mucositis, esophagitis, and dermatitis occurred in 8%, 8%, and 8% (1 each) of IMRT patients and in 18%, 5%, and 14% (4, 1, and 3 patients) of the CRT group, respectively. No acute Grade 4 toxicity occurred. The most common late toxicity was Grade 1 xerostomia (n = 8, 23%). Conclusions: Treatment of

Salivary Gland Tumors Treated With Adjuvant Intensity-Modulated Radiotherapy With or Without Concurrent Chemotherapy

International Nuclear Information System (INIS)

Schoenfeld, Jonathan D.; Sher, David J.; Norris, Charles M.; Haddad, Robert I.; Posner, Marshall R.; Balboni, Tracy A.; Tishler, Roy B.

2012-01-01

Purpose: To analyze the recent single-institution experience of patients with salivary gland tumors who had undergone adjuvant intensity-modulated radiotherapy (IMRT), with or without concurrent chemotherapy. Patients and Methods: We performed a retrospective analysis of 35 salivary gland carcinoma patients treated primarily at the Dana-Farber Cancer Institute between 2005 and 2010 with surgery and adjuvant IMRT. The primary endpoints were local control, progression-free survival, and overall survival. The secondary endpoints were acute and chronic toxicity. The median follow-up was 2.3 years (interquartile range, 1.2–2.8) among the surviving patients. Results: The histologic types included adenoid cystic carcinoma in 15 (43%), mucoepidermoid carcinoma in 6 (17%), adenocarcinoma in 3 (9%), acinic cell carcinoma in 3 (9%), and other in 8 (23%). The primary sites were the parotid gland in 17 (49%), submandibular glands in 6 (17%), tongue in 4 (11%), palate in 4 (11%), and other in 4 (11%). The median radiation dose was 66 Gy, and 22 patients (63%) received CRT. The most common chemotherapy regimen was carboplatin and paclitaxel (n = 14, 64%). A trend was seen for patients undergoing CRT to have more adverse prognostic factors, including Stage T3-T4 disease (CRT, n = 12, 55% vs. n = 4, 31%, p = .29), nodal positivity (CRT, n = 8, 36% vs. n = 1, 8%, p = .10), and positive margins (n = 13, 59% vs. n = 5, 38%, p = .30). One patient who had undergone CRT developed an in-field recurrence, resulting in an overall actuarial 3-year local control rate of 92%. Five patients (14%) developed distant metastases (1 who had undergone IMRT only and 4 who had undergone CRT). Acute Grade 3 mucositis, esophagitis, and dermatitis occurred in 8%, 8%, and 8% (1 each) of IMRT patients and in 18%, 5%, and 14% (4, 1, and 3 patients) of the CRT group, respectively. No acute Grade 4 toxicity occurred. The most common late toxicity was Grade 1 xerostomia (n = 8, 23%). Conclusions: Treatment of

Improvement in toxicity in high risk prostate cancer patients treated with image-guided intensity-modulated radiotherapy compared to 3D conformal radiotherapy without daily image guidance.

Science.gov (United States)

Sveistrup, Joen; af Rosenschöld, Per Munck; Deasy, Joseph O; Oh, Jung Hun; Pommer, Tobias; Petersen, Peter Meidahl; Engelholm, Svend Aage

2014-02-04

Image-guided radiotherapy (IGRT) facilitates the delivery of a very precise radiation dose. In this study we compare the toxicity and biochemical progression-free survival between patients treated with daily image-guided intensity-modulated radiotherapy (IG-IMRT) and 3D conformal radiotherapy (3DCRT) without daily image guidance for high risk prostate cancer (PCa). A total of 503 high risk PCa patients treated with radiotherapy (RT) and endocrine treatment between 2000 and 2010 were retrospectively reviewed. 115 patients were treated with 3DCRT, and 388 patients were treated with IG-IMRT. 3DCRT patients were treated to 76 Gy and without daily image guidance and with 1-2 cm PTV margins. IG-IMRT patients were treated to 78 Gy based on daily image guidance of fiducial markers, and the PTV margins were 5-7 mm. Furthermore, the dose-volume constraints to both the rectum and bladder were changed with the introduction of IG-IMRT. The 2-year actuarial likelihood of developing grade > = 2 GI toxicity following RT was 57.3% in 3DCRT patients and 5.8% in IG-IMRT patients (p analysis, 3DCRT was associated with a significantly increased risk of developing grade > = 2 GI toxicity compared to IG-IMRT (p analysis there was no difference in biochemical progression-free survival between 3DCRT and IG-IMRT. The difference in toxicity can be attributed to the combination of the IMRT technique with reduced dose to organs-at-risk, daily image guidance and margin reduction.

Collimator setting optimization in intensity modulated radiotherapy

International Nuclear Information System (INIS)

Williams, M.; Hoban, P.

2001-01-01

Full text: The aim of this study was to investigate the role of collimator angle and bixel size settings in IMRT when using the step and shoot method of delivery. Of particular interest is minimisation of the total monitor units delivered. Beam intensity maps with bixel size 10 x 10 mm were segmented into MLC leaf sequences and the collimator angle optimised to minimise the total number of MU's. The monitor units were estimated from the maximum sum of positive-gradient intensity changes along the direction of leaf motion. To investigate the use of low resolution maps at optimum collimator angles, several high resolution maps with bixel size 5 x 5 mm were generated. These were resampled into bixel sizes, 5 x 10 mm and 10 x 10 mm and the collimator angle optimised to minimise the RMS error between the original and resampled map. Finally, a clinical IMRT case was investigated with the collimator angle optimised. Both the dose distribution and dose-volume histograms were compared between the standard IMRT plan and the optimised plan. For the 10 x 10 mm bixel maps there was a variation of 5% - 40% in monitor units at the different collimator angles. The maps with a high degree of radial symmetry showed little variation. For the resampled 5 x 5 mm maps, a small RMS error was achievable with a 5 x 10 mm bixel size at particular collimator positions. This was most noticeable for maps with an elongated intensity distribution. A comparison between the 5 x 5 mm bixel plan and the 5 x 10 mm showed no significant difference in dose distribution. The monitor units required to deliver an intensity modulated field can be reduced by rotating the collimator and aligning the direction of leaf motion with the axis of the fluence map that has the least intensity. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

Optimisation of radiotherapy for carcinoma of the parotid gland: a comparison of conventional, three-dimensional conformal, and intensity-modulated techniques

International Nuclear Information System (INIS)

Nutting, Christopher M.; Rowbottom, Carl G.; Cosgrove, Vivian P.; Henk, J. Michael; Dearnaley, David P.; Robinson, Martin H.; Conway, John; Webb, Steve

2001-01-01

Background and purpose: To compare external beam radiotherapy techniques for parotid gland tumours using conventional radiotherapy (RT), three-dimensional conformal radiotherapy (3DCRT), and intensity-modulated radiotherapy (IMRT). To optimise the IMRT techniques, and to produce an IMRT class solution. Materials and methods: The planning target volume (PTV), contra-lateral parotid gland, oral cavity, brain-stem, brain and cochlea were outlined on CT planning scans of six patients with parotid gland tumours. Optimised conventional RT and 3DCRT plans were created and compared with inverse-planned IMRT dose distributions using dose-volume histograms. The aim was to reduce the radiation dose to organs at risk and improve the PTV dose distribution. A beam-direction optimisation algorithm was used to improve the dose distribution of the IMRT plans, and a class solution for parotid gland IMRT was investigated. Results: 3DCRT plans produced an equivalent PTV irradiation and reduced the dose to the cochlea, oral cavity, brain, and other normal tissues compared with conventional RT. IMRT further reduced the radiation dose to the cochlea and oral cavity compared with 3DCRT. For nine- and seven-field IMRT techniques, there was an increase in low-dose radiation to non-target tissue and the contra-lateral parotid gland. IMRT plans produced using three to five optimised intensity-modulated beam directions maintained the advantages of the more complex IMRT plans, and reduced the contra-lateral parotid gland dose to acceptable levels. Three- and four-field non-coplanar beam arrangements increased the volume of brain irradiated, and increased PTV dose inhomogeneity. A four-field class solution consisting of paired ipsilateral coplanar anterior and posterior oblique beams (15, 45, 145 and 170 degree sign from the anterior plane) was developed which maintained the benefits without the complexity of individual patient optimisation. Conclusions: For patients with parotid gland tumours

Limited Advantages of Intensity-Modulated Radiotherapy Over 3D Conformal Radiation Therapy in the Adjuvant Management of Gastric Cancer

International Nuclear Information System (INIS)

Alani, Shlomo; Soyfer, Viacheslav; Strauss, Natan; Schifter, Dan; Corn, Benjamin W.

2009-01-01

Purpose: Although chemoradiotherapy was considered the standard adjuvant treatment for gastric cancer, a recent Phase III trial (Medical Research Council Adjuvant Gastric Infusional Chemotherapy [MAGIC]) did not include radiotherapy in the randomization scheme because it was considered expendable. Given radiotherapy's potential, efforts needed to be made to optimize its use for treating gastric cancer. We assessed whether intensity-modulated radiotherapy (IMRT) could improve upon our published results in patients treated with three-dimensional (3D) conformal therapy. Methods and Materials: Fourteen patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a noncoplanar four-field arrangement. Subsequently, a nine-field IMRT plan was designed using a CMS Xio IMRT version 4.3.3 module. Two IMRT beam arrangements were evaluated: beam arrangement 1 consisted of gantry angles of 0 deg., 53 deg., 107 deg., 158 deg., 204 deg., 255 deg., and 306 deg.. Beam arrangement 2 consisted of gantry angles of 30 deg., 90 deg., 315 deg., and 345 deg.; a gantry angle of 320 deg./couch, 30 deg.; and a gantry angle of 35 o /couch, 312 o . Both the target volume coverage and the dose deposition in adjacent critical organs were assessed in the plans. Dose-volume histograms were generated for the clinical target volume, kidneys, spine, and liver. Results: Comparison of the clinical target volumes revealed satisfactory coverage by the 95% isodose envelope using either IMRT or 3D conformal therapy. However, IMRT was only marginally better than 3D conformal therapy at protecting the spine and kidneys from radiation. Conclusions: IMRT confers only a marginal benefit in the adjuvant treatment of gastric cancer and should be used only in the small subset of patients with risk factors for kidney disease or those with a preexisting nephropathy.

Limited advantages of intensity-modulated radiotherapy over 3D conformal radiation therapy in the adjuvant management of gastric cancer.

Science.gov (United States)

Alani, Shlomo; Soyfer, Viacheslav; Strauss, Natan; Schifter, Dan; Corn, Benjamin W

2009-06-01

Although chemoradiotherapy was considered the standard adjuvant treatment for gastric cancer, a recent Phase III trial (Medical Research Council Adjuvant Gastric Infusional Chemotherapy [MAGIC]) did not include radiotherapy in the randomization scheme because it was considered expendable. Given radiotherapy's potential, efforts needed to be made to optimize its use for treating gastric cancer. We assessed whether intensity-modulated radiotherapy (IMRT) could improve upon our published results in patients treated with three-dimensional (3D) conformal therapy. Fourteen patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a noncoplanar four-field arrangement. Subsequently, a nine-field IMRT plan was designed using a CMS Xio IMRT version 4.3.3 module. Two IMRT beam arrangements were evaluated: beam arrangement 1 consisted of gantry angles of 0 degrees , 53 degrees , 107 degrees , 158 degrees , 204 degrees , 255 degrees , and 306 degrees . Beam arrangement 2 consisted of gantry angles of 30 degrees , 90 degrees , 315 degrees , and 345 degrees ; a gantry angle of 320 degrees /couch, 30 degrees ; and a gantry angle of 35 degrees /couch, 312 degrees . Both the target volume coverage and the dose deposition in adjacent critical organs were assessed in the plans. Dose-volume histograms were generated for the clinical target volume, kidneys, spine, and liver. Comparison of the clinical target volumes revealed satisfactory coverage by the 95% isodose envelope using either IMRT or 3D conformal therapy. However, IMRT was only marginally better than 3D conformal therapy at protecting the spine and kidneys from radiation. IMRT confers only a marginal benefit in the adjuvant treatment of gastric cancer and should be used only in the small subset of patients with risk factors for kidney disease or those with a preexisting nephropathy.

Protocol for the isotoxic intensity modulated radiotherapy (IMRT) in stage III non-small cell lung cancer (NSCLC): a feasibility study.

Science.gov (United States)

Haslett, Kate; Franks, Kevin; Hanna, Gerard G; Harden, Susan; Hatton, Matthew; Harrow, Stephen; McDonald, Fiona; Ashcroft, Linda; Falk, Sally; Groom, Nicki; Harris, Catherine; McCloskey, Paula; Whitehurst, Philip; Bayman, Neil; Faivre-Finn, Corinne

2016-04-15

The majority of stage III patients with non-small cell lung cancer (NSCLC) are unsuitable for concurrent chemoradiotherapy, the non-surgical gold standard of care. As the alternative treatment options of sequential chemoradiotherapy and radiotherapy alone are associated with high local failure rates, various intensification strategies have been employed. There is evidence to suggest that altered fractionation using hyperfractionation, acceleration, dose escalation, and individualisation may be of benefit. The MAASTRO group have pioneered the concept of 'isotoxic' radiotherapy allowing for individualised dose escalation using hyperfractionated accelerated radiotherapy based on predefined normal tissue constraints. This study aims to evaluate whether delivering isotoxic radiotherapy using intensity modulated radiotherapy (IMRT) is achievable. Isotoxic IMRT is a multicentre feasibility study. From June 2014, a total of 35 patients from 7 UK centres, with a proven histological or cytological diagnosis of inoperable NSCLC, unsuitable for concurrent chemoradiotherapy will be recruited. A minimum of 2 cycles of induction chemotherapy is mandated before starting isotoxic radiotherapy. The dose of radiation will be increased until one or more of the organs at risk tolerance or the maximum dose of 79.2 Gy is reached. The primary end point is feasibility, with accrual rates, local control and overall survival our secondary end points. Patients will be followed up for 5 years. The study has received ethical approval (REC reference: 13/NW/0480) from the National Research Ethics Service (NRES) Committee North West-Greater Manchester South. The trial is conducted in accordance with the Declaration of Helsinki and Good Clinical Practice (GCP). The trial results will be published in a peer-reviewed journal and presented internationally. NCT01836692; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

Health-related quality of life using intensity-modulated radiation therapy for post-prostatectomy radiotherapy

International Nuclear Information System (INIS)

Van Gysen, Kirsten L.; Guo, Linxin; Kneebone, Andrew B.; Eade, Thomas N.; Vaux, Kenneth J.; Lazzaro, Enzo M.

2013-01-01

Post-prostatectomy radiotherapy (PPRT) with intensity-modulated radiation therapy (IMRT) has the potential to decrease toxicity by reducing dose to surrounding structures. We assessed its impact on health-related quality of life (HRQoL). PPRT patients were enrolled in a prospective HRQoL database. To be eligible, patients were required to be treated with IMRT and have a minimum of 15-month follow up. HRQoL was assessed at baseline, 3, 9 and 15–24 months using the Expanded Prostate Cancer Index Composite questionnaire. Higher scores reflected better HRQoL. Results were analysed as both population means and as individual scores where a moderate change was 10–20 points and a substantial change was >20 points. There were 64 patients eligible and 83% of the cohort received salvage radiotherapy. Prescribed dose was 64Gy in 32 fractions for adjuvant and 66Gy in 33 fractions for salvage IMRT. Mean function scores for urinary, bowel and sexual domains were similar at baseline and 15 months (83.5, 94.2 and 16.9 vs. 82.2, 93.1 and 14.3, respectively). Mean global physical functioning (51.0 vs. 48.1) and mental functioning (51.6 vs. 54.2) showed no difference over time. Individual patient scores by 2 years showed a >20-point deterioration in urinary (12.5%), bowel (1.6%), sexual function (9.4%), physical functioning (3.1%) and mental functioning (1.6%). This report on HRQoL following post-prostatectomy IMRT demonstrates no variation in mean scores in any domain and only 1.6% of patients reporting a greater than 20-point deterioration between baseline and 15–24 months in bowel function.

Intensity-Modulated Radiotherapy for a Rendu-Osler-Weber Disease Patient with Recurrent Severe Epistaxis: A Case Report

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Maximilian Niyazi

2010-01-01

Full Text Available We present a case of a Rendu-Osler-Weber disease patient with recurrent life threatening epistaxis demanding multiple blood transfusions despite of repetitive endoscopic laser and electrocoagulations, endovascular embolisation, septodermoplasty, and long-term intranasal dressings. As alternative treatment modalities repeatedly failed and the patient became almost permanently dependent on nasal dressing, we performed a highly conformal intensity-modulated radiotherapy of the nasal cavity; a total dose of 50 Gy in 2 Gy single fractions was applied. The therapy was very well tolerated, no acute toxicities occurred. Two weeks after the last radiation dose had been applied, the nasal dressing could be removed without problems. Endoscopical control revealed an almost avascular white mucosa without any trace of bleeding spots; previously existing hemangiomas and crusts had disappeared. After a 1-year-follow up, the patient had no significant recurrent epistaxis.

Intensity-Modulated Radiotherapy for Resected Mesothelioma: The Duke Experience

International Nuclear Information System (INIS)

Miles, Edward F.; Larrier, Nicole A.; Kelsey, Christopher R.; Hubbs, Jessica L.; Ma Jinli; Yoo, Sua; Marks, Lawrence B.

2008-01-01

Purpose: To assess the safety and efficacy of intensity-modulated radiotherapy (IMRT) after extrapleural pneumonectomy for malignant pleural mesothelioma. Methods and Materials: Thirteen patients underwent IMRT after extrapleural pneumonectomy between July 2005 and February 2007 at Duke University Medical Center. The clinical target volume was defined as the entire ipsilateral hemithorax, chest wall incisions, including drain sites, and involved nodal stations. The dose prescribed to the planning target volume was 40-55 Gy (median, 45). Toxicity was graded using the modified Common Toxicity Criteria, and the lung dosimetric parameters from the subgroups with and without pneumonitis were compared. Local control and survival were assessed. Results: The median follow-up after IMRT was 9.5 months. Of the 13 patients, 3 (23%) developed Grade 2 or greater acute pulmonary toxicity (during or within 30 days of IMRT). The median dosimetric parameters for those with and without symptomatic pneumonitis were a mean lung dose (MLD) of 7.9 vs. 7.5 Gy (p = 0.40), percentage of lung volume receiving 20 Gy (V 20 ) of 0.2% vs. 2.3% (p = 0.51), and percentage of lung volume receiving 5 Gy (V 20 ) of 92% vs. 66% (p = 0.36). One patient died of fatal pulmonary toxicity. This patient received a greater MLD (11.4 vs. 7.6 Gy) and had a greater V 20 (6.9% vs. 1.9%), and V 5 (92% vs. 66%) compared with the median of those without fatal pulmonary toxicity. Local and/or distant failure occurred in 6 patients (46%), and 6 patients (46%) were alive without evidence of recurrence at last follow-up. Conclusions: With limited follow-up, 45-Gy IMRT provides reasonable local control for mesothelioma after extrapleural pneumonectomy. However, treatment-related pulmonary toxicity remains a significant concern. Care should be taken to minimize the dose to the remaining lung to achieve an acceptable therapeutic ratio

PET/CT scanning guided intensity-modulated radiotherapy in treatment of recurrent ovarian cancer

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Du, Xue-lian, E-mail: duxuelian23800@yahoo.com.cn [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China); Jiang, Tao, E-mail: melody23800@yahoo.com.cn [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China); Sheng, Xiu-gui, E-mail: jnsd2000@yahoo.cn [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China); Li, Qing-shui, E-mail: lqs1966@126.com [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China); Wang, Cong, E-mail: jnwc1981@hotmail.com [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China); Yu, Hao, E-mail: jnyh2200@sina.com [Department of Gynecologic Oncology, Shandong Cancer Hospital, Jinan 250117 (China); Shandong Academy of Medical Science, Jinan 250012 (China)

2012-11-15

Objective: This study was undertaken to evaluate the clinical contribution of positron emission tomography using {sup 18}F-fluorodeoxyglucose and integrated computer tomography (FDG-PET/CT) guided intensity-modulated radiotherapy (IMRT) for treatment of recurrent ovarian cancer. Materials and methods: Fifty-eight patients with recurrent ovarian cancer from 2003 to 2008 were retrospectively studied. In these patients, 28 received PET/CT guided IMRT (PET/CT-IMRT group), and 30 received CT guided IMRT (CT-IMRT group). Treatment plans, tumor response, toxicities and survival were evaluated. Results: Changes in GTV delineation were found in 10 (35.7%) patients based on PET-CT information compared with CT data, due to the incorporation of additional lymph node metastases and extension of the metastasis tumor. PET/CT guided IMRT improved tumor response compared to CT-IMRT group (CR: 64.3% vs. 46.7%, P = 0.021; PR: 25.0% vs. 13.3%, P = 0.036). The 3-year overall survival was significantly higher in the PET-CT/IMRT group than control (34.1% vs. 13.2%, P = 0.014). Conclusions: PET/CT guided IMRT in recurrent ovarian cancer patients improved the delineation of GTV and reduce the likelihood of geographic misses and therefore improve the clinical outcome.

Carotid sparing intensity modulated radiotherapy on early glottic cancer: Preliminary study

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Choi, Hoon Sik; Jeong, Bae Kwon; Jeong, Ho Jin; Song, Jin Ho; Kim, Jin Pyeong; Park, Jung Je; Woo, Seung Hoon; Kang, Ki Mun [Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju (Korea, Republic of)

2016-03-15

To compare the dose distribution between carotid sparing intensity modulated radiotherapy (IMRT) and opposed lateral field technique (LAFT), and to determine the effects of carotid sparing IMRT in early glottic cancer patients who have risk factors for atherosclerosis. Ten early glottic cancer patients were treated with carotid sparing IMRT. For each patient, the conventional LAFT plan was developed for comparison. IMRT and LAFT plans were compared in terms of planning target volume (PTV) coverage, conformity index, homogeneity index, and the doses to planning organ at risk volume (PRV) for carotid arteries, spinal cord and pharyngeal constrictor muscle. Recurrence was not observed in any patients during the follow-up period. V95% for PTV showed no significant difference between IMRT and LAFT plans, while V100% was significantly higher in the IMRT plan (95.5% vs. 94.6%, p = 0.005). The homogeneity index (11.6%) and conformity index (1.4) in the IMRT plan were significantly better than those in the LAFT plans (8.5% and 5.1, respectively) (p = 0.005). The median V5Gy (90.0%), V25Gy (13.5%), and V50Gy (0%) for carotid artery PRV in the IMRT plan were significantly lower than those in the LAFT plan (99.1%, 89.0%, and 77.3%, respectively) (p = 0.005). Our study suggests that carotid sparing IMRT can significantly decrease the dose to carotid arteries compared to LAFT, and it would be considered for early glottic cancer patient with high risk of atherosclerosis.

Dose reduction to normal tissues as compared to the gross tumor by using intensity modulated radiotherapy in thoracic malignancies

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Bhalla NK

2006-08-01

Full Text Available Abstract Background and purpose Intensity modulated radiotherapy (IMRT is a powerful tool, which might go a long way in reducing radiation doses to critical structures and thereby reduce long term morbidities. The purpose of this paper is to evaluate the impact of IMRT in reducing the dose to the critical normal tissues while maintaining the desired dose to the volume of interest for thoracic malignancies. Materials and methods During the period January 2002 to March 2004, 12 patients of various sites of malignancies in the thoracic region were treated using physical intensity modulator based IMRT. Plans of these patients treated with IMRT were analyzed using dose volume histograms. Results An average dose reduction of the mean values by 73% to the heart, 69% to the right lung and 74% to the left lung, with respect to the GTV could be achieved with IMRT. The 2 year disease free survival was 59% and 2 year overall survival was 59%. The average number of IMRT fields used was 6. Conclusion IMRT with inverse planning enabled us to achieve desired dose distribution, due to its ability to provide sharp dose gradients at the junction of tumor and the adjacent critical organs.

Intensity-Modulated Radiotherapy for Locally Advanced Non-Small-Cell Lung Cancer: A Dose-Escalation Planning Study

International Nuclear Information System (INIS)

Lievens, Yolande; Nulens, An; Gaber, Mousa Amr; Defraene, Gilles; De Wever, Walter; Stroobants, Sigrid; Van den Heuvel, Frank

2011-01-01

Purpose: To evaluate the potential for dose escalation with intensity-modulated radiotherapy (IMRT) in positron emission tomography-based radiotherapy planning for locally advanced non-small-cell lung cancer (LA-NSCLC). Methods and Materials: For 35 LA-NSCLC patients, three-dimensional conformal radiotherapy and IMRT plans were made to a prescription dose (PD) of 66 Gy in 2-Gy fractions. Dose escalation was performed toward the maximal PD using secondary endpoint constraints for the lung, spinal cord, and heart, with de-escalation according to defined esophageal tolerance. Dose calculation was performed using the Eclipse pencil beam algorithm, and all plans were recalculated using a collapsed cone algorithm. The normal tissue complication probabilities were calculated for the lung (Grade 2 pneumonitis) and esophagus (acute toxicity, grade 2 or greater, and late toxicity). Results: IMRT resulted in statistically significant decreases in the mean lung (p <.0001) and maximal spinal cord (p = .002 and 0005) doses, allowing an average increase in the PD of 8.6-14.2 Gy (p ≤.0001). This advantage was lost after de-escalation within the defined esophageal dose limits. The lung normal tissue complication probabilities were significantly lower for IMRT (p <.0001), even after dose escalation. For esophageal toxicity, IMRT significantly decreased the acute NTCP values at the low dose levels (p = .0009 and p <.0001). After maximal dose escalation, late esophageal tolerance became critical (p <.0001), especially when using IMRT, owing to the parallel increases in the esophageal dose and PD. Conclusion: In LA-NSCLC, IMRT offers the potential to significantly escalate the PD, dependent on the lung and spinal cord tolerance. However, parallel increases in the esophageal dose abolished the advantage, even when using collapsed cone algorithms. This is important to consider in the context of concomitant chemoradiotherapy schedules using IMRT.

Risk factors for postoperative complications after total laryngectomy following radiotherapy or chemoradiation

DEFF Research Database (Denmark)

Wulff, N B; Kristensen, C.A.; Andersen, E

2015-01-01

OBJECTIVES: To determine the rates of and risk factors for postoperative complications following total laryngectomy in patients treated with radiotherapy or chemoradiation. DESIGN: Retrospective longitudinal study. SETTING: Tertiary medical centres. PARTICIPANTS: A total of 143 patients undergoin...

Intensity-Modulated Radiotherapy for Tumors of the Nasal Cavity and Paranasal Sinuses: Clinical Outcomes and Patterns of Failure

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Wiegner, Ellen A.; Daly, Megan E.; Murphy, James D.; Abelson, Jonathan; Chapman, Chris H.; Chung, Melody; Yu, Yao; Colevas, A. Dimitrios; Kaplan, Michael J.; Fischbein, Nancy; Le, Quynh-Thu [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Chang, Daniel T., E-mail: dtchang@stanford.edu [Department of Radiation Oncology, Stanford University, Stanford, CA (United States)

2012-05-01

Purpose: To report outcomes in patients treated with intensity-modulated radiotherapy (IMRT) for tumors of the paranasal sinuses and nasal cavity (PNS/NC). Methods/Materials: Between June 2000 and December 2009, 52 patients with tumors of the PNS/NC underwent postoperative or definitive radiation with IMRT. Twenty-eight (54%) patients had squamous cell carcinoma (SCC). Twenty-nine patients (56%) received chemotherapy. The median follow-up was 26.6 months (range, 2.9-118.4) for all patients and 30.9 months for living patients. Results: Eighteen patients (35%) developed local-regional failure (LRF) at median time of 7.2 months. Thirteen local failures (25%) were observed, 12 in-field and 1 marginal. Six regional failures were observed, two in-field and four out-of-field. No patients treated with elective nodal radiation had nodal regional failure. Two-year local-regional control (LRC), in-field LRC, freedom from distant metastasis (FFDM), and overall survival (OS) were 64%, 74%, 71%, and 66% among all patients, respectively, and 43%, 61%, 61%, and 53% among patients with SCC, respectively. On multivariate analysis, SCC and >1 subsite involved had worse LRC (p = 0.0004 and p = 0.046, respectively) and OS (p = 0.003 and p = 0.046, respectively). Cribriform plate invasion (p = 0.005) and residual disease (p = 0.047) also had worse LRC. Acute toxicities included Grade {>=}3 mucositis in 19 patients (37%), and Grade 3 dermatitis in 8 patients (15%). Six patients had Grade {>=}3 late toxicity including one optic toxicity. Conclusions: IMRT for patients with PNS/NC tumors has good outcomes compared with historical series and is well tolerated. Patients with SCC have worse LRC and OS. LRF is the predominant pattern of failure.

Hypofractionated intensity-modulated radiotherapy with temozolomide chemotherapy may alter the patterns of failure in patients with glioblastoma multiforme

International Nuclear Information System (INIS)

Reddy, Krishna; Chen, Changhu; Gaspar, Laurie E.; Kavanagh, Brian D.

2014-01-01

The objective of this study was to report the patterns of failure in patients with glioblastoma multiforme (GBM) treated on a phase II trial of hypofractionated intensity-modulated radiotherapy (hypo-IMRT) with concurrent and adjuvant temozolomide (TMZ). Patients with newly diagnosed GBM post-resection received postoperative hypo-IMRT to 60Gy in 10 fractions. TMZ was given concurrently at 75mg/m 2 /day for 28 consecutive days and adjuvantly at 150–200mg/m 2 /day for 5 days every 28 days. Radiographic failure was defined as any new T1-enhancing lesion or biopsy-confirmed progressive enhancement at the primary site. MRIs obtained at the time of failure were fused to original hypo-IMRT plans. Central, in-field, marginal and distant failure were defined as ≥95%, 80% to 95%, any to 80% and 0% of the volume of a recurrence receiving 60Gy, respectively. Twenty-four patients were treated on the trial. Median follow-up was 14.8 months (range 2.7–34.2). Seventeen of 24 patients experienced radiographic failure: one central, five in-field, two marginal, eight distant and one both in-field and distant. Two of the eight distant failures presented with leptomeningeal disease. Two other patients died without evidence of radiographic recurrence. Five of 24 patients demonstrated asymptomatic, gradually progressive in-field T1 enhancement, suggestive of post-treatment changes, without clear evidence of failure; three of these patients received a biopsy/second resection, with 100% radiation necrosis found. The median overall survival of this group was 33.0 months. A 60-Gy hypo-IMRT treatment delivered in 6-Gy fractions with TMZ altered the patterns of failure in GBM, with more distant failures.

Intensity modulated radiotherapy with concurrent chemotherapy for larynx preservation of advanced resectable hypopharyngeal cancer

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Chao Hsing-Lung

2010-05-01

Full Text Available Abstract Background To analyze the rate of larynx preservation in patients of locally advanced hypopharyngeal cancer treated with intensity modulated radiotherapy (IMRT plus concurrent chemotherapy, and compare the results with patients treated with primary surgery. Methods Between January 2003 and November 2007, 14 patients were treated with primary surgery and 33 patients were treated with concurrent chemoradiotherapy (CCRT using IMRT technique. Survival rate, larynx preservation rate were calculated with the Kaplan-Meier method. Multivariate analysis was conducted for significant prognostic factors with Cox-regression method. Results The median follow-up was 19.4 months for all patients, and 25.8 months for those alive. The 5-year overall survival rate was 33% and 44% for primary surgery and definitive CCRT, respectively (p = 0.788. The 5-year functional larynx-preservation survival after IMRT was 40%. Acute toxicities were common, but usually tolerable. The rates of treatment-related mucositis (≥ grade 2 and pharyngitis (≥ grade 3 were higher in the CCRT group. For multivariate analysis, treatment response and cricoid cartilage invasion strongly correlated with survival. Conclusions IMRT plus concurrent chemotherapy may preserve the larynx without compromising survival. Further studies on new effective therapeutic agents are essential.

Conformal intensity-modulated radiotherapy (IMRT) delivered by robotic linac - testing IMRT to the limit?

International Nuclear Information System (INIS)

Webb, S.

1999-01-01

In this paper it is proposed that intensity-modulated radiotherapy (IMRT) could be delivered optimally by a short-length linac mounted on a robotic arm. The robot would allow the linac to 'plant' narrow pencils of photon radiation with any orientation (excluding zones within which the linac and couch might collide) relative to the planning target volume (PTV). The treatment is specified by the trajectory of the robot and by the number of monitor units (MUs) delivered at each robotic orientation. An inverse-planning method to determine the optimum robotic trajectory is presented. It is shown that for complex PTVs, specifically those with concavities in their outline, the conformality of the treatment is improved by the use of a complex trajectory in comparison with a less complex constrained trajectory and this improvement is quantified. It is concluded that robotic linac delivery would lead to a great flexibility in those IMRT treatments requiring very complicated dose distributions with complex 3D shapes. However, even using very fast computers, the goal of determining whether robotic linac delivery is the ultimate IMRT cannot be conclusively reached at present. (author)

Postoperative radiotherapy of uterine sarcoma: A multicentric retrospective study

International Nuclear Information System (INIS)

Champetier, C.; Cowen, D.; Hannoun-Levi, J.M.; Resbeut, M.; Azria, D.; Salem, N.; Tessier, E.; Ellis, S.

2011-01-01

Purpose. - Surgery is the treatment of choice for localized uterine sarcomas. We conducted a retrospective study to define prognostic factors. Patients and methods. - We studied 111 cases of patients treated by adjuvant radiotherapy for uterine sarcoma in seven French centers. The median decline was 31 months. We conducted a univariate analysis to identify factors correlated with local recurrence. The statistically significant factors were studied in multivariate analysis by Cox model. Results. - The median dose of external beam radiotherapy was 45 Gy. Forty-three percent of patients had vaginal vault brachytherapy and 21 % chemotherapy. Only 6.3 % of patients had complications of acute grade III and 8.1 % of long-term sequelae of radiotherapy. The survival rate at 5 years was 74.6 %. They noted 12.6 % of isolated locoregional recurrences, against 29.7 % for distant recurrences, 80 % were pulmonary. Factors correlated with the risk of locoregional relapse were menopausal status (P = 0.045) and surgical margins suspicious or not healthy (P = 0.0095). The chemotherapy did not improve overall survival or disease free survival but the numbers were low. Conclusion. - The postoperative radiotherapy provides good local control in this disease. Brachytherapy is sometimes done, but it does not improve local control. Chemotherapy is not a standard localized stage but the rate of metastatic recurrence calls for the development of strategies involving systemic treatment with radiotherapy. (authors)

Treatment outcome of localized prostate cancer by 70 Gy hypofractionated intensity-modulated radiotherapy with a customized rectal balloon

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Kim, Hyun Jung; Kim, Jun Won; Hong, Sung Joon; Rha, Koon Ho; Lee, Chang Geol; Yang, Seung Choul; Choi, Young Deuk; Suh, Chang Ok; Cho, Jae Ho [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2014-09-15

We aimed to analyze the treatment outcome and long-term toxicity of 70 Gy hypofractionated intensity-modulated radiotherapy (IMRT) for localized prostate cancer using a customized rectal balloon. We reviewed medical records of 86 prostate cancer patients who received curative radiotherapy between January 2004 and December 2011 at our institution. Patients were designated as low (12.8%), intermediate (20.9%), or high risk (66.3%). Thirty patients received a total dose of 70 Gy in 28 fractions over 5 weeks via IMRT (the Hypo-IMRT group); 56 received 70.2 Gy in 39 fractions over 7 weeks via 3-dimensional conformal radiotherapy (the CF-3DRT group, which served as a reference for comparison). A customized rectal balloon was placed in Hypo-IMRT group throughout the entire radiotherapy course. Androgen deprivation therapy was administered to 47 patients (Hypo-IMRT group, 17; CF-3DRT group, 30). Late genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated according to the Radiation Therapy Oncology Group criteria. The median follow-up period was 74.4 months (range, 18.8 to 125.9 months). The 5-year actuarial biochemical relapse-free survival rates for low-, intermediate-, and high-risk patients were 100%, 100%, and 88.5%, respectively, for the Hypo-IMRT group and 80%, 77.8%, and 63.6%, respectively, for the CF-3DRT group (p < 0.046). No patient presented with acute or late GU toxicity > or =grade 3. Late grade 3 GI toxicity occurred in 2 patients (3.6%) in the CF-3DRT group and 1 patient (3.3%) in the Hypo-IMRT group. Hypo-IMRT with a customized rectal balloon resulted in excellent biochemical control rates with minimal toxicity in localized prostate cancer patients.

High-dose intensity-modulated radiotherapy for prostate cancer using daily fiducial marker-based position verification: acute and late toxicity in 331 patients

International Nuclear Information System (INIS)

Lips, Irene M; Dehnad, Homan; Gils, Carla H van; Boeken Kruger, Arto E; Heide, Uulke A van der; Vulpen, Marco van

2008-01-01

We evaluated the acute and late toxicity after high-dose intensity-modulated radiotherapy (IMRT) with fiducial marker-based position verification for prostate cancer. Between 2001 and 2004, 331 patients with prostate cancer received 76 Gy in 35 fractions using IMRT combined with fiducial marker-based position verification. The symptoms before treatment (pre-treatment) and weekly during treatment (acute toxicity) were scored using the Common Toxicity Criteria (CTC). The goal was to score late toxicity according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) scale with a follow-up time of at least three years. Twenty-two percent of the patients experienced pre-treatment grade ≥ 2 genitourinary (GU) complaints and 2% experienced grade 2 gastrointestinal (GI) complaints. Acute grade 2 GU and GI toxicity occurred in 47% and 30%, respectively. Only 3% of the patients developed acute grade 3 GU and no grade ≥ 3 GI toxicity occurred. After a mean follow-up time of 47 months with a minimum of 31 months for all patients, the incidence of late grade 2 GU and GI toxicity was 21% and 9%, respectively. Grade ≥ 3 GU and GI toxicity rates were 4% and 1%, respectively, including one patient with a rectal fistula and one patient with a severe hemorrhagic cystitis (both grade 4). In conclusion, high-dose intensity-modulated radiotherapy with fiducial marker-based position verification is well tolerated. The low grade ≥ 3 toxicity allows further dose escalation if the same dose constraints for the organs at risk will be used

High-dose intensity-modulated radiotherapy for prostate cancer using daily fiducial marker-based position verification: acute and late toxicity in 331 patients

Directory of Open Access Journals (Sweden)

Boeken Kruger Arto E

2008-05-01

Full Text Available Abstract We evaluated the acute and late toxicity after high-dose intensity-modulated radiotherapy (IMRT with fiducial marker-based position verification for prostate cancer. Between 2001 and 2004, 331 patients with prostate cancer received 76 Gy in 35 fractions using IMRT combined with fiducial marker-based position verification. The symptoms before treatment (pre-treatment and weekly during treatment (acute toxicity were scored using the Common Toxicity Criteria (CTC. The goal was to score late toxicity according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC scale with a follow-up time of at least three years. Twenty-two percent of the patients experienced pre-treatment grade ≥ 2 genitourinary (GU complaints and 2% experienced grade 2 gastrointestinal (GI complaints. Acute grade 2 GU and GI toxicity occurred in 47% and 30%, respectively. Only 3% of the patients developed acute grade 3 GU and no grade ≥ 3 GI toxicity occurred. After a mean follow-up time of 47 months with a minimum of 31 months for all patients, the incidence of late grade 2 GU and GI toxicity was 21% and 9%, respectively. Grade ≥ 3 GU and GI toxicity rates were 4% and 1%, respectively, including one patient with a rectal fistula and one patient with a severe hemorrhagic cystitis (both grade 4. In conclusion, high-dose intensity-modulated radiotherapy with fiducial marker-based position verification is well tolerated. The low grade ≥ 3 toxicity allows further dose escalation if the same dose constraints for the organs at risk will be used.

Neural stem cell sparing by linac based intensity modulated stereotactic radiotherapy in intracranial tumors

International Nuclear Information System (INIS)

Oehler, Julia; Brachwitz, Tim; Wendt, Thomas G; Banz, Nico; Walther, Mario; Wiezorek, Tilo

2013-01-01

Neurocognitive decline observed after radiotherapy (RT) for brain tumors in long time survivors is attributed to radiation exposure of the hippocampus and the subventricular zone (SVZ). The potential of sparing capabilities for both structures by optimized intensity modulated stereotactic radiotherapy (IMSRT) is investigated. Brain tumors were irradiated by stereotactic 3D conformal RT or IMSRT using m3 collimator optimized for PTV and for sparing of the conventional OARs (lens, retina, optic nerve, chiasm, cochlea, brain stem and the medulla oblongata). Retrospectively both hippocampi and SVZ were added to the list of OAR and their dose volume histograms were compared to those from two newly generated IMSRT plans using 7 or 14 beamlets (IMSRT-7, IMSRT-14) dedicated for optimized additional sparing of these structures. Conventional OAR constraints were kept constant. Impact of plan complexity and planning target volume (PTV) topography on sparing of both hippocampi and SVZ, conformity index (CI), the homogeneity index (HI) and quality of coverage (QoC) were analyzed. Limits of agreement were used to compare sparing of stem cell niches with either IMSRT-7 or IMSRT-14. The influence of treatment technique related to the topography ratio between PTV and OARs, realized in group A-D, was assessed by a mixed model. In 47 patients CI (p ≤ 0.003) and HI (p < 0.001) improved by IMSRT-7, IMSRT-14, QoC remained stable (p ≥ 0.50) indicating no compromise in radiotherapy. 90% of normal brain was exposed to a significantly higher dose using IMSRT. IMSRT-7 plans resulted in significantly lower biologically effective doses at all four neural stem cell structures, while contralateral neural stem cells are better spared compared to ipsilateral. A further increase of the number of beamlets (IMSRT-14) did not improve sparing significantly, so IMSRT-7 and IMSRT-14 can be used interchangeable. Patients with tumors contacting neither the subventricular zone nor the cortex benefit

Study on the photoneutrons produced in 15 MV medical linear accelerators : Comparison of three dimensional conformal radiotherapy and intensity modulated radiotherapy

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Yang, Oh Nam [Gangneung Asan Hospital, Gangneung (Korea, Republic of); Yang, Oh Nam; Lim, Cheong Hwan [Hanseo Univ., Seosan (Korea, Republic of)

2012-12-15

Intensity-modulated radiotherapy(IMRT) have the ability to provide better dose conformity and sparing of critical normal tissues than three-dimensional radiotherapy(3DCRT). Especially, with the benefit of health insurance in 2011, its use now increasingly in many modern radiotherapy departments. Also the use of linear accelerator with high-energy photon beams over 10 MV is increasing. As is well known, these linacs have the capacity to produce photoneutrons due to photonuclear reactions in materials with a large atomic number such as the target, flattening filters, collimators, and multi-leaf collimators(MLC). MLC-based IMRT treatments increase the monitor units and the probability of production of photoneutrons from photon-induced nuclear reactions. The purpose of this study is to quantitatively evaluate the dose of photoneutrons produced from 3DCRT and IMRT technique for Rando phantom in cervical cancer. We performed the treatment plans with 3DCRT and IMRT technique using Rando phantom for treatment of cervical cancer. An Rando phantom placed on the couch in the supine position was irradiated using 15 MV photon beams. Optically stimulated luminescence dosimeters(OSLD) were attached to 4 different locations (abdomen, chest, head and neck, eyes) and from center of field size and measured 5 times each of locations. Measured neutron dose from IMRT technique increased by 9.0, 8.6, 8.8, and 14 times than 3DCRT technique for abdomen, chest, head and neck, and eyes, respectively. When using IMRT with 15 MV photon beams, the photoneutrons contributed a significant portion on out-of-field. It is difficult to prevent high energy photon beams to produce the photoneutrons due to physical properties, if necessary, It is difficult to prevent high energy photon beams to produce the photoneutrons due to physical properties, if necessary, it is need to provide the additional safe shielding on a linear accelerator and should therefore reduce the out-of-field dose.

Study on the photoneutrons produced in 15 MV medical linear accelerators : Comparison of three dimensional conformal radiotherapy and intensity modulated radiotherapy

International Nuclear Information System (INIS)

Yang, Oh Nam; Yang, Oh Nam; Lim, Cheong Hwan

2012-01-01

Intensity-modulated radiotherapy(IMRT) have the ability to provide better dose conformity and sparing of critical normal tissues than three-dimensional radiotherapy(3DCRT). Especially, with the benefit of health insurance in 2011, its use now increasingly in many modern radiotherapy departments. Also the use of linear accelerator with high-energy photon beams over 10 MV is increasing. As is well known, these linacs have the capacity to produce photoneutrons due to photonuclear reactions in materials with a large atomic number such as the target, flattening filters, collimators, and multi-leaf collimators(MLC). MLC-based IMRT treatments increase the monitor units and the probability of production of photoneutrons from photon-induced nuclear reactions. The purpose of this study is to quantitatively evaluate the dose of photoneutrons produced from 3DCRT and IMRT technique for Rando phantom in cervical cancer. We performed the treatment plans with 3DCRT and IMRT technique using Rando phantom for treatment of cervical cancer. An Rando phantom placed on the couch in the supine position was irradiated using 15 MV photon beams. Optically stimulated luminescence dosimeters(OSLD) were attached to 4 different locations (abdomen, chest, head and neck, eyes) and from center of field size and measured 5 times each of locations. Measured neutron dose from IMRT technique increased by 9.0, 8.6, 8.8, and 14 times than 3DCRT technique for abdomen, chest, head and neck, and eyes, respectively. When using IMRT with 15 MV photon beams, the photoneutrons contributed a significant portion on out-of-field. It is difficult to prevent high energy photon beams to produce the photoneutrons due to physical properties, if necessary, It is difficult to prevent high energy photon beams to produce the photoneutrons due to physical properties, if necessary, it is need to provide the additional safe shielding on a linear accelerator and should therefore reduce the out-of-field dose

Postoperative Intensity-Modulated Arc Therapy for Cervical and Endometrial Cancer: A Prospective Report on Toxicity

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Vandecasteele, Katrien; Tummers, Philippe; Makar, Amin; Eijkeren, Marc van; Delrue, Louke; Denys, Hannelore; Lambert, Bieke; Beerens, Anne-Sophie; Van den Broecke, Rudy; Lambein, Kathleen; Fonteyne, Valérie; De Meerleer, Gert

2012-01-01

Purpose: To report on toxicity after postoperative intensity-modulated arc therapy (IMAT) for cervical (CC) and endometrial cancer (EC). Methods and Materials: Twenty-four CC and 41 EC patients were treated with postoperative IMAT. If indicated, para-aortic lymph node irradiation (preventive or when affected, PALN) and/or concomitant cisplatin (40 mg/m², weekly) was administered. The prescribed dose for IMAT was 45 Gy (CC, 25 fractions) and 46 Gy (EC, 23 fractions), followed by a brachytherapeutic boost if possible. Radiation-related toxicity was assessed prospectively. The effect of concomitant cisplatin and PALN irradiation was evaluated. Results: Regarding acute toxicity (n = 65), Grade 3 and 2 acute gastrointestinal toxicity was observed in zero and 63% of patients (79% CC, 54% EC), respectively. Grade 3 and 2 acute genitourinary toxicity was observed in 1% and 18% of patients, respectively. Grade 2 (21%) and 3 (12%) hematologic toxicity (n = 41) occurred only in CC patients. Seventeen percent of CC patients and 2% of EC patients experienced Grade 2 fatigue and skin toxicity, respectively. Adding cisplatin led to an increase in Grade >2 nausea (57% vs. 9%; p = 0.01), Grade 2 nocturia (24% vs. 4%; p = 0.03), Grade ≥2 hematologic toxicity (38% vs. nil, p = 0.003), Grade ≥2 leukopenia (33% vs. nil, p = 0.009), and a strong trend toward more fatigue (14% vs. 2%; p = 0.05). Para-aortic lymph node irradiation led to an increase of Grade 2 nocturia (31% vs. 4%, p = 0.008) and a strong trend toward more Grade >2 nausea (44% vs. 18%; p = 0.052). Regarding late toxicity (n = 45), no Grade 3 or 4 late toxicity occurred. Grade 2 gastrointestinal toxicity, genitourinary toxicity, and fatigue occurred in 4%, 9%, and 1% of patients. Neither concomitant cisplatin nor PALN irradiation increased late toxicity rates. Conclusions: Postoperative IMAT for EC or CC is associated with low acute and late toxicity. Concomitant chemotherapy and PALN irradiation influences acute but

A Novel Dose Constraint to Reduce Xerostomia in Head-and-Neck Cancer Patients Treated With Intensity-Modulated Radiotherapy

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Strigari, Lidia; Benassi, Marcello; Arcangeli, Giorgio; Bruzzaniti, Vicente; Giovinazzo, Giuseppe; Marucci, Laura

2010-01-01

Purpose: To investigate the predictors of incidence and duration of xerostomia (XT) based on parotid glands (PG), submandibular glands (SMG), and both glands taken as a whole organ (TG) in head-and-neck cancer patients treated with intensity-modulated radiotherapy. Methods and Materials: A prospective study was initiated in May 2003. Sixty-three head-and-neck patients (44 with nasopharynx cancer) were included in the analysis. Using the dose-volume histogram the PG, SMG, and TG mean doses were calculated. Unstimulated and stimulated salivary flow were measured and XT-related questionnaires were compiled before and at 3, 6, 12, 18, and 24 months after radiotherapy. Salivary gland toxicity was evaluated using the Radiation Therapy Oncology Group scale, and Grade ≥3 toxicity was used as the endpoint. The XT incidence was investigated according to descriptive statistics and univariate and multivariate analysis. The Bonferroni method was used for multiple comparison adjustment. Results: After a reduced flow at 3 months after radiotherapy, recovery of salivary flow was observed over time. Primary site and salivary gland mean doses and volumes were identified in univariate analysis as prognostic factors. Multivariate analysis confirmed that TG mean dose (p = 0.00066) and pretreatment stimulated salivary flow (p = 0.00420) are independent factors for predicting XT. Conclusion: The TG mean dose correlates with XT as assessed by Radiation Therapy Oncology Group criteria, salivary output, and XT-related questionnaires. Our results suggest that TG mean dose is a candidate dose constraint for reducing XT, requiring considerably more validation in non-nasopharyngeal cancer patients.

Segmental and dynamic intensity-modulated radiotherapy delivery techniques for micro-multileaf collimator

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Agazaryan, Nzhde; Solberg, Timothy D.

2003-01-01

A leaf sequencing algorithm has been implemented to deliver segmental and dynamic multileaf collimated intensity-modulated radiotherapy (SMLC-IMRT and DMLC-IMRT, respectively) using a linear accelerator equipped with a micro-multileaf collimator (mMLC). The implementation extends a previously published algorithm for the SMLC-IMRT to include the dynamic MLC-IMRT method and several dosimetric considerations. The algorithm has been extended to account for the transmitted radiation and minimize the leakage between opposing and neighboring leaves. The underdosage problem associated with the tongue-and-groove design of the MLC is significantly reduced by synchronizing the MLC leaf movements. The workings of the leaf sequencing parameters have been investigated and the results of the planar dosimetric investigations show that the sequencing parameters affect the measured dose distributions as intended. Investigations of clinical cases suggest that SMLC and DMLC delivery methods produce comparable results with leaf sequences obtained by root-mean-square (RMS) errors specification of 1.5% and lower, approximately corresponding to 20 or more segments. For SMLC-IMRT, there is little to be gained by using an RMS error specification smaller than 2%, approximately corresponding to 15 segments; however, more segments directly translate to longer treatment time and more strain on the MLC. The implemented leaf synchronization method does not increase the required monitor units while it reduces the measured TG underdoses from a maximum of 12% to a maximum of 3% observed with single field measurements of representative clinical cases studied

Dosimetric validation of new semiconductor diode dosimetry system for intensity modulated radiotherapy

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Rajesh Kinhikar

2012-01-01

Full Text Available Introduction: The new diode Isorad was validated for intensity modulated radiotherapy (IMRT and the observations during the validation are reported. Materials and Methods: The validation includes intrinsic precision, post-irradiation stability, dose linearity, dose-rate effect, angular response, source to surface (SSD dependence, field size dependence, and dose calibration. Results: The intrinsic precision of the diode was more than 1% (1 σ. The linearity found in the whole range of dose analyzed was 1.93% (R 2 = 1. The minimum and maximum variation in the measured and calculated dose were found to be 0.78% (with 25 MU at ioscentre and 4.8% (with 1000 MU at isocentre, respectively. The maximal variation in angular response with respect to arbitrary angle 0° found was 1.31%. The diode exhibited a 51.7% and 35% decrease in the response in the 35 cm and 20 cm SSD range, respectively. The minimum and the maximum variation in the measured dose from the diode and calculated dose were 0.82% (5 cm × 5 cm and 3.75% (30 cm × 30 cm, respectively. At couch 270°, the response of the diode was found to vary maximum by 1.4% with ΁ 60 gantry angle. Mean variation between measured dose with diode and planned dose by TPS was found to be 1.3% (SD 0.75 for IMRT patient-specific quality assurance. Conclusion: For the evaluation of IMRT, use of cylindrical diode is strongly recommended.

Locoregionally advanced nasopharyngeal carcinoma treated with intensity-modulated radiotherapy plus concurrent weekly cisplatin with or without neoadjuvant chemotherapy

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Wee, Chan Woo; Keam, Bhum Suk; Heo, Dae Seog; Sung, Myung Whun; Won, Tae Bin; Wu, Hong Gyun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

2015-06-15

The outcomes of locoregionally advanced nasopharyngeal carcinoma patients treated with concurrent chemoradiation (CCRT) using intensity-modulated radiotherapy (IMRT) with/without neoadjuvant chemotherapy (NCT) were evaluated. Eighty-three patients who underwent NCT followed by CCRT (49%) or CCRT with/without adjuvant chemotherapy (51%) were reviewed. To the gross tumor, 67.5 Gy was prescribed. Weekly cisplatin was used as concurrent chemotherapy. With a median follow-up of 49.4 months, the 5-year local control, regional control, distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival rates were 94.7%, 89.3%, 77.8%, 68.0%, and 81.8%, respectively. In multivariate analysis, the American Joint Committee on Cancer stage (p = 0.016) and N stage (p = 0.001) were negative factors for DMFS and DFS, respectively. Overall, NCT demonstrated no benefit and an increased risk of severe hematologic toxicity. However, compared to patients treated with CCRT alone, NCT showed potential of improving DMFS in stage IV patients. CCRT using IMRT resulted in excellent local control and survival outcome. Without evidence of survival benefit from phase III randomized trials, NCT should be carefully administered in locoregionally advanced nasopharyngeal carcinoma patients who are at high-risk of developing distant metastasis and radiotherapy-related mucositis. The results of ongoing trials are awaited.

Locoregionally advanced nasopharyngeal carcinoma treated with intensity-modulated radiotherapy plus concurrent weekly cisplatin with or without neoadjuvant chemotherapy

International Nuclear Information System (INIS)

Wee, Chan Woo; Keam, Bhum Suk; Heo, Dae Seog; Sung, Myung Whun; Won, Tae Bin; Wu, Hong Gyun

2015-01-01

The outcomes of locoregionally advanced nasopharyngeal carcinoma patients treated with concurrent chemoradiation (CCRT) using intensity-modulated radiotherapy (IMRT) with/without neoadjuvant chemotherapy (NCT) were evaluated. Eighty-three patients who underwent NCT followed by CCRT (49%) or CCRT with/without adjuvant chemotherapy (51%) were reviewed. To the gross tumor, 67.5 Gy was prescribed. Weekly cisplatin was used as concurrent chemotherapy. With a median follow-up of 49.4 months, the 5-year local control, regional control, distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival rates were 94.7%, 89.3%, 77.8%, 68.0%, and 81.8%, respectively. In multivariate analysis, the American Joint Committee on Cancer stage (p = 0.016) and N stage (p = 0.001) were negative factors for DMFS and DFS, respectively. Overall, NCT demonstrated no benefit and an increased risk of severe hematologic toxicity. However, compared to patients treated with CCRT alone, NCT showed potential of improving DMFS in stage IV patients. CCRT using IMRT resulted in excellent local control and survival outcome. Without evidence of survival benefit from phase III randomized trials, NCT should be carefully administered in locoregionally advanced nasopharyngeal carcinoma patients who are at high-risk of developing distant metastasis and radiotherapy-related mucositis. The results of ongoing trials are awaited

Postoperative Chemotherapy for Medulloblastoma

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J Gordon Millichap

2005-03-01

Full Text Available The survival rate and cognitive function of 43 children, age <3 years, with medulloblastoma treated with intensive postoperative chemotherapy alone, without radiotherapy, were determined at the University of Wurzburg and other centers in Germany Chemotherapy consisted of three two-month cycles of cyclophosphamide, methotrexate, vincristine, carboplatin, and etoposide.

A comparison of swallowing dysfunction after three-dimensional conformal and intensity-modulated radiotherapy. A systematic review by the Italian Head and Neck Radiotherapy Study Group

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Ursino, Stefano; Morganti, Riccardo; Cristaudo, Agostino; Paiar, Fabiola; D'Angelo, Elisa; Lohr, Frank; Mazzola, Rosario; Merlotti, Anna; Russi, Elvio Grazioso; Musio, Daniela; Alterio, Daniela; Bacigalupo, Almalina

2017-01-01

Dysphagia is one of the most important treatment-related side effects in head and neck cancer (HNC), as it can lead to severe life-threating complications such as aspiration pneumonia and malnutrition. Intensity-modulated radiotherapy (IMRT) could reduce swallowing dysfunction by producing a concave dose distribution and reducing doses to the swallowing-related organs at risk (SWOARs). The aim of this study was to review the current literature in order to compare swallowing outcomes between IMRT and three-dimensional conformal radiotherapy (3DCRT). A search was conducted in the PubMed and Embase databases to identify studies on swallowing outcomes, both clinically and/or instrumentally assessed, after 3DCRT and IMRT. Dysphagia-specific quality of life and objective instrumental data are summarized and discussed. A total of 262 papers were retrieved from the searched databases. An additional 23 papers were retrieved by hand-searching the reference lists. Ultimately, 22 papers were identified which discussed swallowing outcomes after 3DCRT and IMRT for HNC. No outcomes from randomized trials were identified. Despite several methodological limitations, reports from the current literature seem to suggest better swallowing outcomes with IMRT compared to 3DCRT. Further improvements are likely to result from the increased use of IMRT plans optimized for SWOAR sparing. (orig.) [de

Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

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Moraes, Fabio Ynoe de; Neves-Junior, Wellington Furtado Pimenta; Hanna, Samir Abdallah; Carvalho, Heloisa de Andrade; Laufer, Ilya

2016-01-01

Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and non randomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future. (author)

Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

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Moraes, Fabio Ynoe de; Neves-Junior, Wellington Furtado Pimenta; Hanna, Samir Abdallah; Carvalho, Heloisa de Andrade [Hospital Sirio-Libanes, Sao Paulo, SP (Brazil). Departamento de Radioterapia; Taunk, Neil Kanth; Yamada, Yoshiya [Memorial Sloan Kettering Cancer Center, Department of Radiation Oncology, New York, NY (United States); Laufer, Ilya, E-mail: fymoraes@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Neurosurgery, New York, NY (United States)

2016-02-15

Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and non randomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future. (author)

Postoperative radiotherapy for locally advanced gastric cancer

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Lee, M. Z.; Chun, H. C.; Kim, I. S.; Chung, T. J. [Hanyang Univ., Seoul (Korea, Republic of). Coll. of Medicine

1997-06-01

Radical gastrectomy is main treatment of gastric cancer. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adjuvant radiotherapy with 36Gy or more were evaluated. Median age was 60years(range 28-66 yrs). Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively. Chemotherapy was given to all patients except two. Five-year overall survival and disease-free survival rate were 36.6% and 33.6T, respectively. Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and E-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six patients(8.8%) had weigh loss more than 10%. Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high. Five-year survival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival. Furthermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored. (author).

Phase II study evaluating consolidation whole abdominal intensity-modulated radiotherapy (IMRT in patients with advanced ovarian cancer stage FIGO III - The OVAR-IMRT-02 Study

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Eichbaum Michael H

2011-01-01

Full Text Available Abstract Background The prognosis for patients with advanced FIGO stage III epithelial ovarian cancer remains poor despite the aggressive standard treatment, consisting of maximal cytoreductive surgery and platinum-based chemotherapy. The median time to recurrence is less than 2 years, with a 5-years survival rate of -20-25%. Recurrences of the disease occur mostly intraperitoneally. Ovarian cancer is a radiosensitive tumor, so that the use of whole abdominal radiotherapy (WAR as a consolidation therapy would appear to be a logical strategy. WAR used to be the standard treatment after surgery before the chemotherapy era; however, it has been almost totally excluded from the treatment of ovarian cancer during the past decade because of its high toxicity. Modern intensity-modulated radiation therapy (IMRT has the potential of sparing organs at risk like kidneys, liver, and bone marrow while still adequately covering the peritoneal cavity with a homogenous dose. Our previous phase I study showed for the first time the clinical feasibility of intensity-modulated WAR and pointed out promising results concerning treatment tolerance. The current phase-II study succeeds to the phase-I study to further evaluate the toxicity of this new treatment. Methods/design The OVAR-IMRT-02 study is a single-center one arm phase-II trial. Thirty seven patients with optimally debulked ovarian cancer stage FIGO III having a complete remission after chemotherapy will be treated with intensity-modulated WAR as a consolidation therapy. A total dose of 30 Gy in 20 fractions of 1.5 Gy will be applied to the entire peritoneal cavity including the liver surface and the pelvic and para-aortic node regions. Organ at risk are kidneys, liver (except the 1 cm-outer border, heart, vertebral bodies and pelvic bones. Primary endpoint is tolerability; secondary objectives are toxicity, quality of life, progression-free and overall survival. Discussion Intensity-modulated WAR provides

Phase II study evaluating consolidation whole abdominal intensity-modulated radiotherapy (IMRT) in patients with advanced ovarian cancer stage FIGO III - The OVAR-IMRT-02 Study

International Nuclear Information System (INIS)

Rochet, Nathalie; Debus, Juergen; Kieser, Meinhard; Sterzing, Florian; Krause, Sonja; Lindel, Katja; Harms, Wolfgang; Eichbaum, Michael H; Schneeweiss, Andreas; Sohn, Christof

2011-01-01

The prognosis for patients with advanced FIGO stage III epithelial ovarian cancer remains poor despite the aggressive standard treatment, consisting of maximal cytoreductive surgery and platinum-based chemotherapy. The median time to recurrence is less than 2 years, with a 5-years survival rate of -20-25%. Recurrences of the disease occur mostly intraperitoneally. Ovarian cancer is a radiosensitive tumor, so that the use of whole abdominal radiotherapy (WAR) as a consolidation therapy would appear to be a logical strategy. WAR used to be the standard treatment after surgery before the chemotherapy era; however, it has been almost totally excluded from the treatment of ovarian cancer during the past decade because of its high toxicity. Modern intensity-modulated radiation therapy (IMRT) has the potential of sparing organs at risk like kidneys, liver, and bone marrow while still adequately covering the peritoneal cavity with a homogenous dose. Our previous phase I study showed for the first time the clinical feasibility of intensity-modulated WAR and pointed out promising results concerning treatment tolerance. The current phase-II study succeeds to the phase-I study to further evaluate the toxicity of this new treatment. The OVAR-IMRT-02 study is a single-center one arm phase-II trial. Thirty seven patients with optimally debulked ovarian cancer stage FIGO III having a complete remission after chemotherapy will be treated with intensity-modulated WAR as a consolidation therapy. A total dose of 30 Gy in 20 fractions of 1.5 Gy will be applied to the entire peritoneal cavity including the liver surface and the pelvic and para-aortic node regions. Organ at risk are kidneys, liver (except the 1 cm-outer border), heart, vertebral bodies and pelvic bones. Primary endpoint is tolerability; secondary objectives are toxicity, quality of life, progression-free and overall survival. Intensity-modulated WAR provides a new promising option in the consolidation treatment of

Assessment of renal function after conformal radiotherapy and intensity-modulated radiotherapy by functional 1H-MRI and 23Na-MRI

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Haneder, S.; Michaely, H.J.; Schoenberg, S.O.; Konstandin, S.; Schad, L.R.; Siebenlist, K.; Wertz, H.; Wenz, F.; Lohr, F.; Boda-Heggemann, J.

2012-01-01

Purpose: Adjuvant radiochemotherapy (RCHT) improves survival of patients with locally advanced gastric cancer. Conventional three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to a significant amount of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides excellent target coverage with improved kidney sparing. Few long-term results on IMRT for gastric cancer, however, have been published. Functional magnetic resonance imaging (fMRI) at 3.0 T including blood oxygenation-level dependent (BOLD) imaging, diffusion-weighted imaging (DWI) and, for the first time, 23 Na imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT. Patients and methods Four disease-free patients (2 after 3D-CRT and 2 after IMRT; FU for all patients > 5 years) were included in this feasibility study. Morphological sequences, axial DWI images, 2D-gradient echo (GRE)-BOLD images, and 23 Na images were acquired. Mean values/standard deviations for ( 23 Na), the apparent diffusion coefficient (ADC), and R2 * values were calculated for the upper/middle/lower parts of both kidneys. Corticomedullary 23 Na-concentration gradients were determined. Results: Surprisingly, IG-IMRT patients showed no morphological alterations and no statistically significant differences of ADC and R2 * values in all renal parts. Values for mean corticomedullary 23 Na-concentration matched those for healthy volunteers. Results were similar in 3D-CRT patients, except for the cranial part of the left kidney. This was atrophic and presented significantly reduced functional parameters (p = 0.001 - p = 0.033). Reduced ADC values indicated reduced cell density and reduced extracellular space. Cortical and medullary R2 * values of the left cranial kidney in the 3D-CRT group were higher, indicating more deoxygenated hemoglobin due to reduced blood flow/oxygenation. ( 23 Na) of the renal cranial parts in the 3D-CRT group was significantly reduced

Postoperative radiotherapy for malignant tumors of the submandibular gland

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Storey, Mark R.; Garden, Adam S.; Morrison, William H.; Eicher, Susan A.; Schechter, Naomi R.; Ang, K. Kian

2001-01-01

Purpose: This retrospective study assessed the outcome and patterns of failure for patients with malignant submandibular tumors treated with surgery and postoperative radiation. Methods and Materials: Between 1965 and 1995, 83 patients aged 11-83 years old received postoperative radiotherapy after resection of submandibular gland carcinomas. The most common radiation technique was an appositional field to the submandibular gland bed using electrons either alone or mixed with photons. Primary tumor bed doses ranged from 50 to 69 Gy (median, 60 Gy). Regional lymph nodes (ipsilateral Levels I-IV) were irradiated in 66 patients to a median dose of 50 Gy. Follow-up time ranged from 5 to 321 months (median, 82 months). Results: Actuarial locoregional control rates were 90%, 88%, and 88% at 2, 5, and 10 years, respectively. The corresponding disease-free survival rates were 76%, 60%, and 53%, because 27 of 74 patients (36%) who attained locoregional control developed distant metastases. Adenocarcinoma, high-grade histology, and treatment during the earlier years of the study were associated with worse locoregional control and disease-free survival. The median survival times for patients with and without locoregional control were 183 months and 19 months, respectively. Actuarial 2-, 5-, and 10-year survival rates were 84%, 71%, and 55%, respectively. Late complications occurred in 8 patients (osteoradionecrosis, 5 patients). Conclusions: High-risk cancers of the submandibular gland have a historic control rate of approximately 50% when treated with surgery alone. In the current series, locoregional control rates for high-risk patients with submandibular gland cancers treated with surgery and postoperative radiotherapy were excellent, with an actuarial locoregional control rate of 88% at 10 years

Image-guided intensity-modulated radiotherapy for prostate cancer: Dose constraints for the anterior rectal wall to minimize rectal toxicity

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Peterson, Jennifer L., E-mail: peterson.jennifer2@mayo.edu [Department of Radiation Oncology, Mayo Clinic Florida, Jacksonville, FL (United States); Buskirk, Steven J. [Department of Radiation Oncology, Mayo Clinic Florida, Jacksonville, FL (United States); Heckman, Michael G.; Diehl, Nancy N. [Section of Biostatistics, Mayo Clinic Florida, Jacksonville, FL (United States); Bernard, Johnny R. [Section of Biostatistics, Mayo Clinic Florida, Jacksonville, FL (United States); Department of Radiation Oncology, Southern Ohio Medical Center, Portsmouth, OH (United States); Tzou, Katherine S.; Casale, Henry E.; Bellefontaine, Louis P.; Serago, Christopher; Kim, Siyong; Vallow, Laura A.; Daugherty, Larry C.; Ko, Stephen J. [Department of Radiation Oncology, Mayo Clinic Florida, Jacksonville, FL (United States)

2014-04-01

Rectal adverse events (AEs) are a major concern with definitive radiotherapy (RT) treatment for prostate cancer. The anterior rectal wall is at the greatest risk of injury as it lies closest to the target volume and receives the highest dose of RT. This study evaluated the absolute volume of anterior rectal wall receiving a high dose to identify potential ideal dose constraints that can minimize rectal AEs. A total of 111 consecutive patients with Stage T1c to T3a N0 M0 prostate cancer who underwent image-guided intensity-modulated RT at our institution were included. AEs were graded according to the Common Terminology Criteria for Adverse Events, version 4.0. The volume of anterior rectal wall receiving 5 to 80 Gy in 2.5-Gy increments was determined. Multivariable Cox regression models were used to identify cut points in these volumes that led to an increased risk of early and late rectal AEs. Early AEs occurred in most patients (88%); however, relatively few of them (13%) were grade ≥2. At 5 years, the cumulative incidence of late rectal AEs was 37%, with only 5% being grade ≥2. For almost all RT doses, we identified a threshold of irradiated absolute volume of anterior rectal wall above which there was at least a trend toward a significantly higher rate of AEs. Most strikingly, patients with more than 1.29, 0.73, or 0.45 cm{sup 3} of anterior rectal wall exposed to radiation doses of 67.5, 70, or 72.5 Gy, respectively, had a significantly increased risk of late AEs (relative risks [RR]: 2.18 to 2.72; p ≤ 0.041) and of grade ≥ 2 early AEs (RR: 6.36 to 6.48; p = 0.004). Our study provides evidence that definitive image-guided intensity-modulated radiotherapy (IG-IMRT) for prostate cancer is well tolerated and also identifies dose thresholds for the absolute volume of anterior rectal wall above which patients are at greater risk of early and late complications.

Image-guided intensity-modulated radiotherapy for prostate cancer: Dose constraints for the anterior rectal wall to minimize rectal toxicity

International Nuclear Information System (INIS)

Peterson, Jennifer L.; Buskirk, Steven J.; Heckman, Michael G.; Diehl, Nancy N.; Bernard, Johnny R.; Tzou, Katherine S.; Casale, Henry E.; Bellefontaine, Louis P.; Serago, Christopher; Kim, Siyong; Vallow, Laura A.; Daugherty, Larry C.; Ko, Stephen J.

2014-01-01

Rectal adverse events (AEs) are a major concern with definitive radiotherapy (RT) treatment for prostate cancer. The anterior rectal wall is at the greatest risk of injury as it lies closest to the target volume and receives the highest dose of RT. This study evaluated the absolute volume of anterior rectal wall receiving a high dose to identify potential ideal dose constraints that can minimize rectal AEs. A total of 111 consecutive patients with Stage T1c to T3a N0 M0 prostate cancer who underwent image-guided intensity-modulated RT at our institution were included. AEs were graded according to the Common Terminology Criteria for Adverse Events, version 4.0. The volume of anterior rectal wall receiving 5 to 80 Gy in 2.5-Gy increments was determined. Multivariable Cox regression models were used to identify cut points in these volumes that led to an increased risk of early and late rectal AEs. Early AEs occurred in most patients (88%); however, relatively few of them (13%) were grade ≥2. At 5 years, the cumulative incidence of late rectal AEs was 37%, with only 5% being grade ≥2. For almost all RT doses, we identified a threshold of irradiated absolute volume of anterior rectal wall above which there was at least a trend toward a significantly higher rate of AEs. Most strikingly, patients with more than 1.29, 0.73, or 0.45 cm 3 of anterior rectal wall exposed to radiation doses of 67.5, 70, or 72.5 Gy, respectively, had a significantly increased risk of late AEs (relative risks [RR]: 2.18 to 2.72; p ≤ 0.041) and of grade ≥ 2 early AEs (RR: 6.36 to 6.48; p = 0.004). Our study provides evidence that definitive image-guided intensity-modulated radiotherapy (IG-IMRT) for prostate cancer is well tolerated and also identifies dose thresholds for the absolute volume of anterior rectal wall above which patients are at greater risk of early and late complications

Postoperative radiotherapy for low grade glioma of the brain

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Chun, Ha Chung; Lee, Myung Za

2000-01-01

To evaluate the effectiveness and tolerance of postoperative external beam radiotherapy for patients with low grade glioma of the brain and define the optimal radiotherapeutic regimen. Between June, 1985 and May, 1998, 72 patients with low grade gliomas were treated with postoperative radiotherapy immediately following surgery. Median age was 37 years with range of 11 to 76 years. Forty one patients were male and 31 patients were female with male to female ratio of 1.3:1. Of those patients, 15 underwent biopsy alone and remaining 57 did subtotal resection. The distribution of the patients according to histologic type was as follows: astrocytomas-42 patients (58%), mixed oligodendrogliomas-19 patients (27%), oligodendrogliomas-11 patients (15%). Two patients were treated with whole brain irradiation followed by cone down boost and remaining 70 patients were treated with localized field with appropriate margin. All of the patients were treated with conventional once a day fractionation. Most of patients received total tumor dose of 5000-5500 cGy. The overall 5 and 7 year survival rates for entire group of 72 patients were 61% and 50%. Corresponding disease free survival rates for entire patients were 53% and 45%, respectively. The 5 and 7 year overall survival rates for astrocytomas, mixed oligodendrogliomas, and oligodendrogliomas were 48% and 45%, 76% and 56%, and 80% and 52%, respectively. Patients who underwent subtotal resection showed better survival rates than those who did biopsy alone. The overall 5 year survival rates for subtotal resection patients and biopsy alone patients were 67% and 43%, respectively. Forty six patients who were 40 years or younger survived better than 26 patients who were 41 years or older (overall survival rate at 5 years, 69% vs 45%). Although one patient was not able to complete the treatment because of neurological deterioration, there was no significant treatment related acute toxicities. Postoperative radiotherapy was safe and

Improved Planning Time and Plan Quality Through Multicriteria Optimization for Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Craft, David L.; Hong, Theodore S.; Shih, Helen A.; Bortfeld, Thomas R.

2012-01-01

Purpose: To test whether multicriteria optimization (MCO) can reduce treatment planning time and improve plan quality in intensity-modulated radiotherapy (IMRT). Methods and Materials: Ten IMRT patients (5 with glioblastoma and 5 with locally advanced pancreatic cancers) were logged during the standard treatment planning procedure currently in use at Massachusetts General Hospital (MGH). Planning durations and other relevant planning information were recorded. In parallel, the patients were planned using an MCO planning system, and similar planning time data were collected. The patients were treated with the standard plan, but each MCO plan was also approved by the physicians. Plans were then blindly reviewed 3 weeks after planning by the treating physician. Results: In all cases, the treatment planning time was vastly shorter for the MCO planning (average MCO treatment planning time was 12 min; average standard planning time was 135 min). The physician involvement time in the planning process increased from an average of 4.8 min for the standard process to 8.6 min for the MCO process. In all cases, the MCO plan was blindly identified as the superior plan. Conclusions: This provides the first concrete evidence that MCO-based planning is superior in terms of both planning efficiency and dose distribution quality compared with the current trial and error–based IMRT planning approach.

The impact of postoperative supraclavicular radiotherapy on tracheoesophageal groove lymph node metastasis in esophageal carcinoma

International Nuclear Information System (INIS)

Qian Pudong; Lu Jinchen; Mei Zeru; Zhu Jun

2005-01-01

Objective: To evaluate the prognostic factors of tracheoesophageal groove lymph node (TEGLN) metastasis in postoperative esophageal carcinoma. Methods: From January 1996 to December 1997, 101 postoperative cervical and thoracic esophageal carcinoma patients proved absence from tracheoesophageal groove lymph node (TEGIAN) metastasis before and after operation by physical examination and computer tomography examination were entered into this study. The patients were divided into three groups according to the treatment of supraclavicular region: no prophylactic radiotherapy (group A-, 30 patients); prophylactic radiotherapy with local dose < 45 Gy (Group B-, 71 patients); and prophylactic radiotherapy with local dose ≥45 Gy (Group C-, 19 patients). Radiotherapy was delivered by cobalt- 60 or 6 MV X-ray with the prescribed dose normalized to the point of tracheoesophageal groove, i. e, 5 cm in depth. The tracheoesophageal groove lymph node metastasis after treatment was observed. Results: The incidence of tracheoesophageal groove lymph node metastasis was 20% (6/30), 9.6% (5/71) and 0% (0/19) in groups A, B and C. Univariate analysis showed that there was significant difference of TEGLN metastasis between groups A and C only (P=0.039), but higher dose to supraclavicular region tended to lower the incidence of TEGLN metastasis. Multivariate analysis showed that only prophylactic radiotherapy to the supraclavicular region was independent prognostic factor for TEGLN metastasis (P=0.037). Gender, primary tumor site and pathological stage had no significant impact on TEGLN metastasis. Conclusions: Postoperative prophylactic supraclavicular region irradiation can lower the incidence of tracheoesophageal groove lymph node metastasis in esophageal carcinoma. Radiotherapy dose should not be less than 45 Gy and should be routinely normalized to a point 5 cm deep in the tracheoesophageal groove. (authors)

Cardiac avoidance in breast radiotherapy: a comparison of simple shielding techniques with intensity-modulated radiotherapy

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Landau, David; Adams, Elizabeth J.; Webb, Steve; Ross, Gillian

2001-01-01

Background and purpose: Adjuvant breast radiotherapy (RT) is now part of the routine care of patients with early breast cancer. However, analysis of the Early Breast Cancer Trialists' Collaborative suggests that patients with the lowest risk of dying of breast cancer are at significant risk of cardiac mortality due to longer relapse-free survival. Patients with a significant amount of heart in the high-dose volume have been shown to be at risk of fatal cardiac events. This study was designed to assess whether conformal planning or intensity-modulated radiotherapy (IMRT) techniques allow reduced cardiac irradiation whilst maintaining full target coverage. Material and methods: Ten patients with early breast cancer were available for computed tomography (CT) planning. Each had at least 1 cm maximum heart depth within the posterior border of conventional tangents. For each patient, plans were generated and compared using dose volume histograms for planning target volume (PTV) and organs at risk. The plans included conventional tangents with and without shielding. The shielding was designed to either completely spare the heart or to shield as much heart as possible without compromising PTV coverage. IMRT plans were also prepared using two- and four-field tangential and six-field arc-like beam arrangements. Results: PTV homogeneity was better for the tangential IMRT techniques. For all patients, cardiac irradiation was reduced by the addition of partial cardiac shielding to conventional tangents, without compromise of PTV coverage. The two- and four-field IMRT techniques also reduced heart doses. The average percentage volume of heart receiving >60% of the prescription dose was 4.4% (range 1.0-7.1%) for conventional tangents, 1.5% (0.2-3.9%) for partial shielding, 2.3% (0.5-4.6%) for the two-field IMRT technique and 2.2% (0.4-5.6%) for the four-field IMRT technique. For patients with larger maximum heart depths the four-field IMRT plan achieved greater heart sparing

Parotid-sparing intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma: Preserved parotid function after IMRT on quantitative salivary scintigraphy, and comparison with historical data after conventional radiotherapy

International Nuclear Information System (INIS)

Hsiung, C.-Y.; Ting, H.-M.; Huang, H.-Y.; Lee, C.-H.; Huang, E.-Y.; Hsu, H.-C.

2006-01-01

Purpose: To evaluate the parotid function after parotid-sparing intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC). Methods and Materials: From March 2003 to May 2004, 16 patients with nonmetastatic NPC underwent parotid-sparing IMRT. Eight of these patients had Stage III or IV NPC based on the 1997 American Joint Committee on Cancer staging system. The post-IMRT parotid function was evaluated by quantitative salivary scintigraphy and represented by the maximal excretion ratio (MER) of the parotid gland after sialogogue stimulation. The parotid function of 16 NPC patients who were previously treated with conventional radiotherapy was reviewed as the historical control. Results: In the parotid-sparing IMRT group, all 16 patients were alive and without cancer at the end of follow-up period (median, 24.2 months). The mean parotid MER was 53.5% before radiotherapy, 10.7% at 1 month post-IMRT, and 23.3% at 9 months post-IMRT. In the conventional radiotherapy group, the mean parotid MER was 0.6% at 6 to 12 months postradiotherapy. The difference was statistically significant (23.3% vs. 0.6%, p < 0.001, Mann-Whitney test). In the IMRT group, the mean parotid doses ranged from 33.2 Gy to 58.8 Gy (average, 43.9 Gy). The correlation between the mean parotid dose and the percentage decrease of parotid MER at 9 months post-IMRT (dMER) was statically significant (p = 0.008, Pearson correlation). Conclusions: Although the mean parotid doses are relatively high, the significant preservation of parotid function is achieved with IMRT for NPC patients. The significant correlation between mean parotid dose and parotid dMER demonstrates the dose-function relationship of the parotid gland

Protons Offer Reduced Normal-Tissue Exposure for Patients Receiving Postoperative Radiotherapy for Resected Pancreatic Head Cancer

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Nichols, Romaine C., E-mail: rnichols@floridaproton.org [University of Florida Proton Therapy Institute, Jacksonsville, FL (United States); Huh, Soon N. [University of Florida Proton Therapy Institute, Jacksonsville, FL (United States); Prado, Karl L.; Yi, Byong Y.; Sharma, Navesh K. [Department of Radiation Oncology, University of Maryland, Baltimore, MD (United States); Ho, Meng W.; Hoppe, Bradford S.; Mendenhall, Nancy P.; Li, Zuofeng [University of Florida Proton Therapy Institute, Jacksonsville, FL (United States); Regine, William F. [Department of Radiation Oncology, University of Maryland, Baltimore, MD (United States)

2012-05-01

Purpose: To determine the potential role for adjuvant proton-based radiotherapy (PT) for resected pancreatic head cancer. Methods and Materials: Between June 2008 and November 2008, 8 consecutive patients with resected pancreatic head cancers underwent optimized intensity-modulated radiotherapy (IMRT) treatment planning. IMRT plans used between 10 and 18 fields and delivered 45 Gy to the initial planning target volume (PTV) and a 5.4 Gy boost to a reduced PTV. PTVs were defined according to the Radiation Therapy Oncology Group 9704 radiotherapy guidelines. Ninety-five percent of PTVs received 100% of the target dose and 100% of the PTVs received 95% of the target dose. Normal tissue constraints were as follows: right kidney V18 Gy to <70%; left kidney V18 Gy to <30%; small bowel/stomach V20 Gy to <50%, V45 Gy to <15%, V50 Gy to <10%, and V54 Gy to <5%; liver V30 Gy to <60%; and spinal cord maximum to 46 Gy. Optimized two- to three-field three-dimensional conformal proton plans were retrospectively generated on the same patients. The team generating the proton plans was blinded to the dose distributions achieved by the IMRT plans. The IMRT and proton plans were then compared. A Wilcoxon paired t-test was performed to compare various dosimetric points between the two plans for each patient. Results: All proton plans met all normal tissue constraints and were isoeffective with the corresponding IMRT plans in terms of PTV coverage. The proton plans offered significantly reduced normal-tissue exposure over the IMRT plans with respect to the following: median small bowel V20 Gy, 15.4% with protons versus 47.0% with IMRT (p = 0.0156); median gastric V20 Gy, 2.3% with protons versus 20.0% with IMRT (p = 0.0313); and median right kidney V18 Gy, 27.3% with protons versus 50.5% with IMRT (p = 0.0156). Conclusions: By reducing small bowel and stomach exposure, protons have the potential to reduce the acute and late toxicities of postoperative chemoradiation in this setting.

Indications of elective neck dissection and postoperative radiotherapy for parotid cancers

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Shibata, Tomohisa; Yonezawa, Kouichiro; Morimoto, Koichi; Yamashita, Daisuke; Otsuki, Naoki; Nishimura, Hideki; Sasaki, Ryohei; Nibu, Ken-ichi

2011-01-01

Regional lymph node metastases significantly influence the prognosis of patients with parotid cancer. To assess our indications of elective neck dissection and postoperative radiotherapy for parotid cancer, a retrospective chart review was performed. Between 2001 and 2009, 35 patients with parotid cancer were initially treated at our department. The median follow-up was 30 months (range, 10-90 months). Out of all patients, 31 (89%) patients were preoperatively diagnosed as malignant, while 4 (11%) patients were initially diagnosed as benign. Mucoepidermoid carcinoma was the most common histological type (10 patients). Twenty-two tumors (63%) were pathologically diagnosed as high-grade. The numbers of patients with Stages I, II, III, and IVA were 3, 10, 7, and 15, respectively. Ipsilateral neck dissection (Level II-V) was performed in seven patients with clinically positive neck metastasis (cN+), and in ten patients without lymph node metastasis who had T4 disease, high-grade malignancy, or positive neck (Level II) metastasis during intraoperative evaluation. Postoperative radiotherapy was performed in 24 patients with pathological T4, high-grade malignancy, positive surgical margin, multiple neck metastasis and/or extranodal extension (ENI). Seven of 28 (25%) patients with clinically N0 had pathologically positive neck metastasis (pN+). Regional recurrence developed in one patient with high-grade malignancy and ENI (T4N2b). Disease-specific survival rates for Stages I, II, III, and IVA at 3 years were 100%, 73%, 100%, and 37%, respectively. Loco-regional control rates for pN0 (21 patients) and pN+ (14 patients) at 3 years were 90% and 95%, respectively. Our present favorable loco-regional control supported our current indications of elective neck dissection and postoperative radiotherapy. We also recommend intraoperative biopsy of level IIB nodes to study the need for elective neck dissection. (author)

[Radiotherapy for head and neck squamous cell carcinoma: State of the art and future directions].

Science.gov (United States)

Schick, U; Huguet, F; Pointreau, Y; Pradier, O

2017-10-01

Therapeutic principles of radiation therapy in head and neck carcinomas will be discussed in this review. Intensity-modulated radiotherapy with concomitant cisplatin should be standard. In case of contraindication to chemotherapy, cetuximab is an option, while hyperfractionation should be considered in patients unfit for concomitant treatment. Concomitant chemotherapy should be administered in the presence of extracapsular extensions and positive margins in the postoperative setting. Current research areas such as desescalation in human papillomavirus-positive tumours, adaptive radiotherapy, radiomics and immunotherapy will also be addressed. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Radiotherapy of prostate cancer with or without intensity modulated beams: a planning comparison

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Meerleer, Gert O. de; Vakaet, Luc A.M.L.; Gersem, Werner R.T. de; Wagter, Carlos de; Naeyer, Bart de; Neve, Wilfried de

2000-01-01

Purpose: To evaluate whether intensity modulated radiotherapy (IMRT) by static segmented beams allows the dose to the main portion of the prostate target to escalate while keeping the maximal dose at the anterior rectal wall at 72 Gy. The value of such IMRT plans was analyzed by comparison with non-IMRT plans using the same beam incidences. Methods and Materials: We performed a planning study on the CT data of 32 consecutive patients with localized adenocarcinoma of the prostate. Three fields in the transverse plane with gantry angles of 0 deg. , 116 deg. , and 244 deg. were isocentered at the center of gravity of the target volume (prostate and seminal vesicles). The geometry of the beams was determined by beam's eye view autocontouring of the target volume with a margin of 1.5 cm. In study 1, the beam weights were determined by a human planner (3D-man) or by computer optimization using a biological objective function with (3D-optim-lim) or without (3D-optim-unlim) a physical term to limit target dose inhomogeneity. In study 2, the 3 beam incidences mentioned above were used and in-field uniform segments were added to allow IMRT. Plans with (IMRT-lim) or without (IMRT-unlim) constraints on target dose inhomogeneity were compared. In the IMRT-lim plan, target dose inhomogeneity was constrained between 15% and 20%. After optimization, plans in both studies were normalized to a maximal rectal dose of 72 Gy. Biological (tumor control probability [TCP], normal tissue complication probability [NTCP]) and physical indices for tumor control and normal tissue complication probabilities were computed, as well as the probability of the uncomplicated local control (P+). Results: The IMRT-lim plan was superior to all other plans concerning TCP (p =no. 89%). For bladder, maximal bladder dose was significantly higher in the IMRT-unlim plan compared to all other plans (p no. <=no. 0.0001). P+ was significantly higher in both IMRT-plans than in all other plans. The 3D

Intensity-modulated proton therapy, volumetric-modulated arc therapy, and 3D conformal radiotherapy in anaplastic astrocytoma and glioblastoma. A dosimetric comparison

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Adeberg, S.; Debus, J. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); German Cancer Research Center (DKFZ), Clinical Cooperation Unit Radiation Oncology, Heidelberg (Germany); Harrabi, S.B.; Bougatf, N.; Rieber, J.; Koerber, S.A.; Herfarth, K.; Rieken, S. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Bernhardt, D.; Syed, M.; Sprave, T.; Mohr, A. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Abdollahi, A. [University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Haberer, T. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); Combs, S.E. [Technische Universitaet Muenchen, Department of Radiation Oncology, Muenchen (Germany); Helmholtz Zentrum Muenchen, Institut fuer Innovative Radiotherapie (iRT), Department of Radiation Sciences (DRS), Neuherberg (Germany)

2016-11-15

The prognosis for high-grade glioma (HGG) patients is poor; thus, treatment-related side effects need to be minimized to conserve quality of life and functionality. Advanced techniques such as proton radiation therapy (PRT) and volumetric-modulated arc therapy (VMAT) may potentially further reduce the frequency and severity of radiogenic impairment. We retrospectively assessed 12 HGG patients who had undergone postoperative intensity-modulated proton therapy (IMPT). VMAT and 3D conformal radiotherapy (3D-CRT) plans were generated and optimized for comparison after contouring crucial neuronal structures important for neurogenesis and neurocognitive function. Integral dose (ID), homogeneity index (HI), and inhomogeneity coefficient (IC) were calculated from dose statistics. Toxicity data were evaluated. Target volume coverage was comparable for all three modalities. Compared to 3D-CRT and VMAT, PRT showed statistically significant reductions (p < 0.05) in mean dose to whole brain (-20.2 %, -22.7 %); supratentorial (-14.2 %, -20,8 %) and infratentorial (-91.0 %, -77.0 %) regions; brainstem (-67.6 %, -28.1 %); pituitary gland (-52.9 %, -52.5 %); contralateral hippocampus (-98.9 %, -98.7 %); and contralateral subventricular zone (-62.7 %, -66.7 %, respectively). Fatigue (91.7 %), radiation dermatitis (75.0 %), focal alopecia (100.0 %), nausea (41.7 %), cephalgia (58.3 %), and transient cerebral edema (16.7 %) were the most common acute toxicities. Essential dose reduction while maintaining equal target volume coverage was observed using PRT, particularly in contralaterally located critical neuronal structures, areas of neurogenesis, and structures of neurocognitive functions. These findings were supported by preliminary clinical results confirming the safety and feasibility of PRT in HGG. (orig.) [German] Die Prognose bei ''High-grade''-Gliomen (HGG) ist infaust. Gerade bei diesen Patienten sollten therapieassoziierte Nebenwirkungen minimiert werden

Impact of xerostomia on dysphagia after chemotherapy-intensity-modulated radiotherapy for oropharyngeal cancer: Prospective longitudinal study.

Science.gov (United States)

Vainshtein, Jeffrey M; Samuels, Stuart; Tao, Yebin; Lyden, Teresa; Haxer, Marc; Spector, Matthew; Schipper, Matthew; Eisbruch, Avraham

2016-04-01

The purpose of this study was to assess how xerostomia affects dysphagia. Prospective longitudinal studies of 93 patients with oropharyngeal cancer treated with definitive chemotherapy-intensity-modulated radiotherapy (IMRT). Observer-rated dysphagia (ORD), patient-reported dysphagia (PRD), and patient-reported xerostomia (PRX) assessment of the swallowing mechanics by videofluoroscopy (videofluoroscopy score), and salivary flow rates, were prospectively assessed from pretherapy through 2 years. ORD grades ≥2 were rare and therefore not modeled. Of patients with no/mild videofluoroscopy abnormalities, a substantial proportion had PRD that peaked 3 months posttherapy and subsequently improved. Through 2 years, highly significant correlations were observed between PRX and PRD scores for all patients, including those with no/mild videofluoroscopy abnormalities. Both PRX and videofluoroscopy scores were highly significantly associated with PRD. On multivariate analysis, PRX score was a stronger predictor of PRD than the videofluoroscopy score. Xerostomia contributes significantly to PRD. Efforts to further decrease xerostomia, in addition to sparing parotid glands, may translate into improvements in PRD. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1605-E1612, 2016. © 2015 Wiley Periodicals, Inc.

Quality Assurance Analysis of a Large Multicenter Practice: Does Increased Complexity of Intensity-Modulated Radiotherapy Lead to Increased Error Frequency?

International Nuclear Information System (INIS)

Olson, Adam C.; Wegner, Rodney E.; Scicutella, Carol; Heron, Dwight E.; Greenberger, Joel S.; Huq, M. Saiful; Bednarz, Gregory; Flickinger, John C.

2012-01-01

Purpose: Error reduction is an important concern in clinical medicine. Intensity-modulated radiotherapy (IMRT) is an important advancement in radiation oncology that increases the complexity of treatment, potentially increasing the error risk. We studied the frequency and severity of errors in a large multicenter practice to ascertain the impact of quality improvement interventions over time, IMRT, and type of practice. Methods and Materials: We analyzed prospective data from three academic and 16 community practice sites with 24,775 courses of radiotherapy (9,210 IMRT courses and 15,565 non-IMRT) between January 2006 and December 2009. All IMRT treatment was performed using one centralized dose planning center for all sites. Results: We prospectively identified various errors or potential errors in 0.14 % vs. 0.40 % of the IMRT vs. non-IMRT courses (13/9,210 vs. 62/15,565, p = 0.0004) and excluding potential errors: 0.03 % for IMRT vs. 0.21% for non-IMRT. We developed the Clinical Radiotherapy Error Severity Scale (CRESS) to classify error severity from 1 to 10, with 1 to 3 for potential or completely correctable errors, 4 to 5 for dose variations 5%. Multivariate analyses of CRESS values, severity >4, and any error (including potential) correlated significantly reduced errors with IMRT (p = 0.0001–0.0024) but found no significant difference between the academic and community practice sites and no change in error frequency over time despite implementation of 39 system-wide policy changes by the centralized quality improvement committee. Conclusions: Despite the increase in complexity with IMRT compared with conventional radiotherapy, it can be delivered with reduced error frequency.

Urethra sparing - potential of combined Nickel-Titanium stent and intensity modulated radiation therapy in prostate cancer.

Science.gov (United States)

Thomsen, Jakob Borup; Arp, Dennis Tideman; Carl, Jesper

2012-05-01

To investigate a novel method for sparing urethra in external beam radiotherapy of prostate cancer and to evaluate the efficacy of such a treatment in terms of tumour control using a mathematical model. This theoretical study includes 20 patients previously treated for prostate cancer using external beam radiotherapy. All patients had a Nickel-Titanium (Ni-Ti) stent inserted into the prostate part of urethra. The stent has been used during the treatment course as an internal marker for patient positioning prior to treatment. In this study the stent is used for delineating urethra while intensity modulated radiotherapy was used for lowering dose to urethra. Evaluation of the dose plans were performed using a tumour control probability model based on the concept of uniform equivalent dose. The feasibility of the urethra dose reduction method is validated and a reduction of about 17% is shown to be possible. Calculations suggest a nearly preserved tumour control probability. A new concept for urethra dose reduction is presented. The method relies on the use of a Ni-Ti stent as a fiducial marker combined with intensity modulated radiotherapy. Theoretical calculations suggest preserved tumour control. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A Multiplan Treatment-Planning Framework: A Paradigm Shift for Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Meyer, Robert R.; Zhang, Hao H.; Goadrich, Laura; Nazareth, Daryl P.; Shi Leyuan; D'Souza, Warren D.

2007-01-01

Purpose: To describe a multiplan intensity-modulated radiotherapy (IMRT) planning framework, and to describe a decision support system (DSS) for ranking multiple plans and modeling the planning surface. Methods and Materials: One hundred twenty-five plans were generated sequentially for a head-and-neck case and a pelvic case by varying the dose-volume constraints on each of the organs at risk (OARs). A DSS was used to rank plans according to dose-volume histogram (DVH) values, as well as equivalent uniform dose (EUD) values. Two methods for ranking treatment plans were evaluated: composite criteria and pre-emptive selection. The planning surface determined by the results was modeled using quadratic functions. Results: The DSS provided an easy-to-use interface for the comparison of multiple plan features. Plan ranking resulted in the identification of one to three 'optimal' plans. The planning surface models had good predictive capability with respect to both DVH values and EUD values and generally, errors of <6%. Models generated by minimizing the maximum relative error had significantly lower relative errors than models obtained by minimizing the sum of squared errors. Using the quadratic model, plan properties for one OAR were determined as a function of the other OAR constraint settings. The modeled plan surface can then be used to understand the interdependence of competing planning objectives. Conclusion: The DSS can be used to aid the planner in the selection of the most desirable plan. The collection of quadratic models constructed from the plan data to predict DVH and EUD values generally showed excellent agreement with the actual plan values

Dosimetric Advantage of Intensity-Modulated Radiotherapy for Whole Ventricles in the Treatment of Localized Intracranial Germinoma

International Nuclear Information System (INIS)

Sakanaka, Katsuyuki; Mizowaki, Takashi; Hiraoka, Masahiro

2012-01-01

Purpose: To investigate the dosimetric advantage of intensity-modulated radiotherapy (IMRT) for whole ventricles (WV) in patients with a localized intracranial germinoma receiving induction chemotherapy. Methods and Materials: Data from 12 consecutive patients with localized intracranial germinomas who received induction chemotherapy and radiotherapy were used. Four-field coplanar three-dimensional conformal radiotherapy (3D-CRT) and seven-field coplanar IMRT plans were created. In both plans, 24 Gy was prescribed in 12 fractions for the planning target volume (PTV) involving WV and tumor bed. In IMRT planning, optimization was conducted to reduce the doses to the organs at risk (OARs) as much as possible, keeping the minimum dose equivalent to that of 3D-CRT. The 3D-CRT and IMRT plans were compared in terms of the dose–volume statistics for target coverage and the OARs. Results: IMRT significantly increased the percentage volume of the PTV receiving 24 Gy compared with 3D-CRT (93.5% vs. 84.8%; p = 0.007), while keeping target homogeneity equivalent to 3D-CRT (p = 0.869). The absolute percentage reduction in the irradiated volume of the normal brain receiving 100%, 75%, 50%, and 25% of 24 Gy ranged from 0.7% to 16.0% in IMRT compared with 3D-CRT (p < 0.001). No significant difference was observed in the volume of the normal brain receiving 10% and 5% of 24 Gy between IMRT and 3D-CRT. Conformation number was significantly improved in IMRT (p < 0.001). For other OARs, the mean dose to the cochlea was reduced significantly in IMRT by 22.3% of 24 Gy compared with 3D-CRT (p < 0.001). Conclusions: Compared with 3D-CRT, IMRT for WV improved the target coverage and reduced the irradiated volume of the normal brain in patients with intracranial germinomas receiving induction chemotherapy. IMRT for WV with induction chemotherapy could reduce the late side effects from cranial irradiation without compromising control of the tumor.

Comparison of mucous and cutaneous toxicity of IMRT and of conventional radiotherapy associated with cetuximab; Comparaison de la toxicite muqueuse et cutanee de la RCMI et de la radiotherapie classique associee au cetuximab

Energy Technology Data Exchange (ETDEWEB)

Kreps, S.; Tamby, E.; Dessard Diana, B.; Berges, O.; Botti, M.; Deberne, M.; Henni, M.; Durdux, C.; Housset, M.; Giraud, P. [Hopital europeen Georges-Pompidou, Paris (France)

2011-10-15

The authors report a retrospective assessment of acute, cutaneous and mucous toxicity resulting from an association of cetuximab and conventional conformational radiotherapy, and from an intensity-modulated conformational radiotherapy (IMRT). Seven patients presenting nasopharyngeal, oropharyngeal or hypopharyngeal tumours have been irradiated with intensity modulation, and seven without. It appears that the association of cetuximab and radiotherapy is not well tolerated and requires a close monitoring. Intensity-modulated radiotherapy allows a significant reduction of dose and of toxicity. However, mucous toxicity remains significant. Short communication

Adjuvant whole abdominal intensity modulated radiotherapy (IMRT) for high risk stage FIGO III patients with ovarian cancer (OVAR-IMRT-01) – Pilot trial of a phase I/II study: study protocol

International Nuclear Information System (INIS)

Rochet, Nathalie; Jensen, Alexandra D; Sterzing, Florian; Munter, Marc W; Eichbaum, Michael H; Schneeweiss, Andreas; Sohn, Christof; Debus, Juergen; Harms, Wolfgang

2007-01-01

The prognosis for patients with advanced epithelial ovarian cancer remains poor despite aggressive surgical resection and platinum-based chemotherapy. More than 60% of patients will develop recurrent disease, principally intraperitoneal, and die within 5 years. The use of whole abdominal irradiation (WAI) as consolidation therapy would appear to be a logical strategy given its ability to sterilize small tumour volumes. Despite the clinically proven efficacy of whole abdominal irradiation, the use of radiotherapy in ovarian cancer has profoundly decreased mainly due to high treatment-related toxicity. Modern intensity-modulated radiation therapy (IMRT) could allow to spare kidneys, liver, and bone marrow while still adequately covering the peritoneal cavity with a homogenous dose. The OVAR-IMRT-01 study is a single center pilot trial of a phase I/II study. Patients with advanced ovarian cancer stage FIGO III (R1 or R2< 1 cm) after surgical resection and platinum-based chemotherapy will be treated with whole abdomen irradiation as consolidation therapy using intensity modulated radiation therapy (IMRT) to a total dose of 30 Gy in 1.5 Gy fractions. A total of 8 patients will be included in this trial. For treatment planning bone marrow, kidneys, liver, spinal cord, vertebral bodies and pelvic bones are defined as organs at risk. The planning target volume includes the entire peritoneal cavity plus pelvic and para-aortic node regions. The primary endpoint of the study is the evaluation of the feasibility of intensity-modulated WAI and the evaluation of the study protocol. Secondary endpoint is evaluation of the toxicity of intensity modulated WAI before continuing with the phase I/II study. The aim is to explore the potential of IMRT as a new method for WAI to decrease the dose to kidneys, liver, bone marrow while covering the peritoneal cavity with a homogenous dose, and to implement whole abdominal intensity-modulated radiotherapy into the adjuvant multimodal

Planning magnetic resonance imaging for prostate cancer intensity-modulated radiation therapy: Impact on target volumes, radiotherapy dose and androgen deprivation administration.

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Horsley, Patrick J; Aherne, Noel J; Edwards, Grace V; Benjamin, Linus C; Wilcox, Shea W; McLachlan, Craig S; Assareh, Hassan; Welshman, Richard; McKay, Michael J; Shakespeare, Thomas P

2015-03-01

Magnetic resonance imaging (MRI) scans are increasingly utilized for radiotherapy planning to contour the primary tumors of patients undergoing intensity-modulated radiation therapy (IMRT). These scans may also demonstrate cancer extent and may affect the treatment plan. We assessed the impact of planning MRI detection of extracapsular extension, seminal vesicle invasion, or adjacent organ invasion on the staging, target volume delineation, doses, and hormonal therapy of patients with prostate cancer undergoing IMRT. The records of 509 consecutive patients with planning MRI scans being treated with IMRT for prostate cancer between January 2010 and July 2012 were retrospectively reviewed. Tumor staging and treatment plans before and after MRI were compared. Of the 509 patients, 103 (20%) were upstaged and 44 (9%) were migrated to a higher risk category as a result of findings at MRI. In 94 of 509 patients (18%), the MRI findings altered management. Ninety-four of 509 patients (18%) had a change to their clinical target volume (CTV) or treatment technique, and in 41 of 509 patients (8%) the duration of hormone therapy was changed because of MRI findings. The use of radiotherapy planning MRI altered CTV design, dose and/or duration of androgen deprivation in 18% of patients in this large, single institution series of men planned for dose-escalated prostate IMRT. This has substantial implications for radiotherapy target volumes and doses, as well as duration of androgen deprivation. Further research is required to investigate whether newer MRI techniques can simultaneously fulfill staging and radiotherapy contouring roles. © 2014 Wiley Publishing Asia Pty Ltd.

Recurrence in Region of Spared Parotid Gland After Definitive Intensity-Modulated Radiotherapy for Head and Neck Cancer

International Nuclear Information System (INIS)

Cannon, Donald M.; Lee, Nancy Y.

2008-01-01

Purpose: To discuss the implications of three examples of periparotid recurrence after definitive intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC). Methods and Materials: We present 3 patients with HNC who underwent definitive IMRT with concurrent chemotherapy and later had treatment failure in or near a spared parotid gland. Two patients had bilateral multilevel nodal disease, and all had Level II nodal disease ipsilateral to the site of recurrence. The patients were treated using dose-painting IMRT with a dose of 70 Gy to the gross tumor volume and 59.4 Gy or 54 Gy to the high-risk or low-risk clinical tumor volume, respectively. The parotid glands were spared bilaterally. The patients had not undergone any surgical treatment for HNC before radiotherapy. Results: All patients had treatment failure in the region of a spared parotid gland. Failure in the 2 patients with bilateral multilevel nodal involvement occurred in the periparotid lymph nodes. The third patient developed a dermal metastasis near the tail of a spared parotid gland. On pretreatment imaging, the 2 patients with nodal failure had small nonspecific periparotid nodules that showed no hypermetabolic activity on positron emission tomography. Conclusion: For HNC patients receiving definitive IMRT, nonspecific positron emission tomography-negative periparotid nodules on pretreatment imaging should raise the index of suspicion for subclinical disease in the presence of multilevel or Level II nodal metastases. Additional evaluation of such nodules might be indicated before sparing the ipsilateral parotid gland

Evaluation of the impact of dental artefacts on intensity-modulated radiotherapy planning for the head and neck

International Nuclear Information System (INIS)

Webster, Gareth J.; Rowbottom, Carl G.; Mackay, Ranald I.

2009-01-01

Background and purpose: High density materials create severe artefacts in the computed tomography (CT) scans used for radiotherapy dose calculations. Increased use of intensity-modulated radiotherapy (IMRT) to treat oropharyngeal cancers raises concerns over the accuracy of the resulting dose calculation. This work quantifies their impact and evaluates a simple corrective technique. Materials and methods: Fifteen oropharyngeal patients with severe artefacts were retrospectively planned with IMRT using two different CT/density look-up tables. Each plan was recalculated using a corrected CT dataset to evaluate the dose distribution delivered to the patient. Plan quality in the absence of dental artefacts was similarly assessed. A range of dosimetric and radiobiological parameters were compared pre- and post-correction. Results: Plans using a standard CT/density look-up table (density ≤1.8 g/cm 3 ) revealed inconsistent inter-patient errors, mostly within clinical acceptance, although potentially significantly reducing target coverage for individual patients. Using an extended CT/density look-up table (density ≤10.0 g/cm 3 ) greatly reduced the errors for 13/15 patients. In 2/15 patients with residual errors the CTV extended into the severely affected region and could be corrected by applying a simple manual correction. Conclusions: Use of an extended CT/density look-up table together with a simple manual bulk density correction reduces the impact of dental artefacts on head and neck IMRT planning to acceptable levels.

Feasibility of using intensity-modulated radiotherapy to improve lung sparing in treatment planning for distal esophageal cancer

International Nuclear Information System (INIS)

Chandra, Anurag; Guerrero, Thomas M.; Liu, H. Helen; Tucker, Susan L.; Liao Zhongxing; Wang Xiaochun; Murshed, Hasan; Bonnen, Mark D.; Garg, Amit K.; Stevens, Craig W.; Chang, Joe Y.; Jeter, Melinda D.; Mohan, Radhe; Cox, James D.; Komaki, Ritsuko

2005-01-01

Background and purpose: To evaluate the feasibility whether intensity-modulated radiotherapy (IMRT) can be used to reduce doses to normal lung than three-dimensional conformal radiotherapy (3DCRT) in treating distal esophageal malignancies. Patients and methods: Ten patient cases with cancer of the distal esophagus were selected for a retrospective treatment-planning study. IMRT plans using four, seven, and nine beams (4B, 7B, and 9B) were developed for each patient and compared with the 3DCRT plan used clinically. IMRT and 3DCRT plans were evaluated with respect to PTV coverage and dose-volumes to irradiated normal structures, with statistical comparison made between the two types of plans using the Wilcoxon matched-pair signed-rank test. Results: IMRT plans (4B, 7B, 9B) reduced total lung volume treated above 10 Gy (V 1 ), 20 Gy (V 2 ), mean lung dose (MLD), biological effective volume (V eff ), and lung integral dose (P 1 , 5% for V 2 , and 2.5 Gy for MLD. IMRT improved the PTV heterogeneity (P<0.05), yet conformity was better with 7B-9B IMRT plans. No clinically meaningful differences were observed with respect to the irradiated volumes of spinal cord, heart, liver, or total body integral doses. Conclusions: Dose-volume of exposed normal lung can be reduced with IMRT, though clinical investigations are warranted to assess IMRT treatment outcome of esophagus cancers

Analysis of Biochemical Control and Prognostic Factors in Patients Treated With Either Low-Dose Three-Dimensional Conformal Radiation Therapy or High-Dose Intensity-Modulated Radiotherapy for Localized Prostate Cancer

International Nuclear Information System (INIS)

Vora, Sujay A.; Wong, William W.; Schild, Steven E.; Ezzell, Gary A.; Halyard, Michele Y.

2007-01-01

Purpose: To identify prognostic factors and evaluate biochemical control rates for patients with localized prostate cancer treated with either high-dose intensity-modulated radiotherapy (IMRT) or conventional-dose three-dimensional conformal radiotherapy 3D-CRT. Methods: Four hundred sixteen patients with a minimum follow-up of 3 years (median, 5 years) were included. Two hundred seventy-one patients received 3D-CRT with a median dose of 68.4 Gy (range, 66-71 Gy). The next 145 patients received IMRT with a median dose of 75.6 Gy (range, 70.2-77.4 Gy). Biochemical control rates were calculated according to both American Society for Therapeutic Radiology and Oncology (ASTRO) consensus definitions. Prognostic factors were identified using both univariate and multivariate analyses. Results: The 5-year biochemical control rate was 60.4% for 3D-CRT and 74.1% for IMRT (p < 0.0001, first ASTRO Consensus definition). Using the ASTRO Phoenix definition, the 5-year biochemical control rate was 74.4% and 84.6% with 3D-RT and IMRT, respectively (p = 0.0326). Univariate analyses determined that PSA level, T stage, Gleason score, perineural invasion, and radiation dose were predictive of biochemical control. On multivariate analysis, dose, Gleason score, and perineural invasion remained significant. Conclusion: On the basis of both ASTRO definitions, dose, Gleason score, and perineural invasion were predictive of biochemical control. Intensity-modulated radiotherapy allowed delivery of higher doses of radiation with very low toxicity, resulting in improved biochemical control

Simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) in nasopharyngeal cancer

Energy Technology Data Exchange (ETDEWEB)

Studer, Gabriela [Dept. of Radiation Oncology, Univ. Hospital, Zurich (Switzerland); Peponi, Evangelia; Glanzmann, Christoph; Kunz, Guntram; Renner, Christoph; Tomuschat, Katja

2010-03-15

Purpose: To assess the efficacy and safety of using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) to treat nasopharyngeal cancer (NPC) in a Caucasian cohort. Outcome was analyzed with respect to dose-volume histogram (DVH) values. Patients and Methods: Between 03/2002 and 01/2008, 39 NPC patients underwent SIB-IMRT (37 Caucasians; 31 males; mean age 53 years [16-78 years]). 41% presented with WHO (World Health Organization) type 1 unfavorable histology, 85% with stage III/IV disease. 19 patients had total gross tumor volume (GTV) 16-70 cm{sup 3} (mean 36 cm{sup 3}), while 16 had GTV > 70 cm{sup 3} (73-217 cm{sup 3}; mean 115 cm{sup 3}). All patients with stage II-IV disease received concomitant cisplatin. The prescribed SIB dose delivered to the planning target volume (PTV) was 70 Gy (2.00 Gy/fraction) in 17, 69.6 Gy (2.11 Gy/fraction) in 19, and 66 Gy (2.20 Gy/fraction) in three patients. Results: 3-year local relapse-free, nodal relapse-free, distant metastases-free, disease-free rates and overall survival were 86%, 89%, 85%, 72%, and 85% (median follow-up 30 months [8-71 months]). Histology was a significant prognostic factor concerning overall survival, with worst prognosis in WHO type 1 compared to type 2/3 (75% vs. 93%; p = 0.03). There was a trend in favor of WHO type 2/3 regarding local control (74% vs. 94%; p = 0.052). The PTV DVHs showed a slight left shift compared to reported series. Three patients developed grade 3 late effects (xerostomia [n=2], dysphagia [n=1], hearing loss [n=1]). Conclusion: In comparison with predominantly Asian NPC IMRT series in the literature, chemo-IMRT in the own Caucasian cohort, characterized by less radioresponsive WHO type 1, was equally effective. Treatment tolerance was excellent. (orig.)

Automated Planning of Tangential Breast Intensity-Modulated Radiotherapy Using Heuristic Optimization

International Nuclear Information System (INIS)

Purdie, Thomas G.; Dinniwell, Robert E.; Letourneau, Daniel; Hill, Christine; Sharpe, Michael B.

2011-01-01

Purpose: To present an automated technique for two-field tangential breast intensity-modulated radiotherapy (IMRT) treatment planning. Method and Materials: A total of 158 planned patients with Stage 0, I, and II breast cancer treated using whole-breast IMRT were retrospectively replanned using automated treatment planning tools. The tools developed are integrated into the existing clinical treatment planning system (Pinnacle 3 ) and are designed to perform the manual volume delineation, beam placement, and IMRT treatment planning steps carried out by the treatment planning radiation therapist. The automated algorithm, using only the radio-opaque markers placed at CT simulation as inputs, optimizes the tangential beam parameters to geometrically minimize the amount of lung and heart treated while covering the whole-breast volume. The IMRT parameters are optimized according to the automatically delineated whole-breast volume. Results: The mean time to generate a complete treatment plan was 6 min, 50 s ± 1 min 12 s. For the automated plans, 157 of 158 plans (99%) were deemed clinically acceptable, and 138 of 158 plans (87%) were deemed clinically improved or equal to the corresponding clinical plan when reviewed in a randomized, double-blinded study by one experienced breast radiation oncologist. In addition, overall the automated plans were dosimetrically equivalent to the clinical plans when scored for target coverage and lung and heart doses. Conclusion: We have developed robust and efficient automated tools for fully inversed planned tangential breast IMRT planning that can be readily integrated into clinical practice. The tools produce clinically acceptable plans using only the common anatomic landmarks from the CT simulation process as an input. We anticipate the tools will improve patient access to high-quality IMRT treatment by simplifying the planning process and will reduce the effort and cost of incorporating more advanced planning into clinical practice.

Intensity-modulated radiation therapy for anal carcinoma; Radiotherapie conformationnelle avec modulation d'intensite des cancers de l'anus

Energy Technology Data Exchange (ETDEWEB)

Peiffert, D.; Moreau-Claeys, M.V.; Tournier-Rangeard, L.; Huger, S.; Marchesi, V. [Departement de radiotherapie, centre Alexis-Vautrin, 6, avenue de Bourgogne, 54511 Vandoeuvre-les-Nancy cedex (France)

2011-10-15

Anal canal carcinoma are highly curable by irradiation, combined with chemotherapy in locally advanced disease, with preservation of sphincter function. The clinical target volume for the nodes is extended, often including the inguinal nodes, which is not usual for other pelvic tumours. Acute and late effects are correlated with the volume and dose delivered to organs at risk, i. e. small bowel, bladder and increased by concomitant chemotherapy. Intensity modulated irradiation (IMRT) makes it possible to optimize the dose distribution in this 'complex U shaped' volume, while maintaining the dose distribution for the target volumes. The conversion from conformal irradiation to IMRT necessitates good knowledge of the definition and skills to delineate target volumes and organs at risk, including new volumes needed to optimize the dose distribution. Dosimetric and clinical benefits of IMRT are described, based on early descriptions and evidence-based publication. The growing development of IMRT in anal canal radiotherapy must be encouraged, and long-term benefits should be soon published. Radiation oncologists should precisely learn IMRT recommendations before starting the technique, and evaluate its early and late results for adverse effects, but also for long-term tumour control. (authors)

Risk Factors for Hearing Loss in Patients Treated With Intensity-Modulated Radiotherapy for Head-and-Neck Tumors

International Nuclear Information System (INIS)

Zuur, Charlotte L.; Simis, Yvonne J.; Lamers, Emmy A.; Hart, Augustinus A.; Dreschler, Wouter A.; Balm, Alfons J.; Rasch, Coen R.

2009-01-01

Purpose: Radiotherapy (RT) is a common treatment of head-and-neck carcinoma. The objective of this study was to perform a prospective multivariate assessment of the dose-effect relationship between intensity-modulated RT and hearing loss. Methods and Materials: Pure tone audiometry at 0.250-16 kHz was obtained before and after treatment in 101 patients (202 ears). All patients received full-course intensity-modulated RT (range, 56-70 Gy), with a median cochlear dose of 11.4 Gy (range, 0.2-69.7). Results: Audiometry was performed 1 week before and a median of 9 weeks (range, 1-112) after treatment. The mean hearing deterioration at pure tone average air-conduction 1-2-4 kHz was small (from 28.6 dB HL to 30.1 dB HL). However, individual patients showed clinically significant hearing loss, with 10-dB threshold shift incidences of 13% and 18% at pure tone averages air-conduction 1-2-4 kHz and 8-10-12.5 kHz, respectively. Post-treatment hearing capability was unfavorable in the case of greater inner ear radiation doses (p <0.0001), unfavorable baseline hearing capability (p <0.0001), green-eyed patients (p <0.0001), and older age (p <0.0001). Using multivariate analysis, a prediction of individual hearing capabiltity after treatment was made. Conclusion: RT-induced hearing loss in the mean population is modest. However, clinically significant hearing loss was observed in older patients with green eyes and unfavorable pretreatment hearing. In these patients, the intended radiation dose may be adjusted according to the proposed predictive model, aiming to decrease the risk of ototoxicity.

Image-guided intensity-modulated radiotherapy for patients with locally advanced gastric cancer: a clinical feasibility study.

Science.gov (United States)

Badakhshi, Harun; Gruen, Arne; Graf, Reinhold; Boehmer, Dirk; Budach, Volker

2014-01-01

The aim of this study was to determine the medical and technical feasibility of intensity-modulated radiotherapy (IMRT) in high-risk nonmetastatic gastric cancer stage II and III after primary gastrectomy and D2 lymphadenectomy. A prospective nonrandomized phase II trial was performed on 25 consecutive patients with gastric cancer with high risk (T3-4, N1-3, G2-3, R0-1). The dose delivered was 45 Gy (1.80 Gy per fraction) in IMRT technique. Concurrent 5-fluorouracil-based chemotherapy at 225 mg/m(2) was administered as a continuous intravenous infusion. Primary endpoints were acute gastrointestinal toxicity (CTC 4.0) and technical feasibility of IMRT in regard to dose planning and radiation delivery. Early acute events were defined as clinical and chemical adverse effects of IMRT and concurrent chemotherapy during treatment. By definition, 90 days after the end of IMRT has been evaluated as acute-phase toxicity. No patient had grade 4 or higher acute adverse events. Clinical grade 3 toxicity occurred in two patients (8%) with diarrhea and in one case (4%) with nausea. Hematological changes with grade 3 occurred in three cases (12%) with hemoglobin decrease, in five cases (25%) as leukopenia, and in one case (4%) with thrombocytopenia. The mean dose for liver was 16 Gy and the percentage volume exceeding 30 Gy (V30) was 21%. Mean dose for right and left kidney was 9 and 13 Gy, respectively, and V20 was 9% and 13%, respectively. Heart received a median dose of 15 Gy and V40 was 17%. The mean dose to the bowel was 11 Gy and V40 was 6%. Spinal cord had at maximum 33 Gy in median. Specifics of dose distribution, including the coverage, for the target region were as follows: minimum was 33 Gy, maximum 48.6 Gy, and mean dose 44.6 Gy. The prescribed dose (45 Gy) covered 99% and 95% of planning target volume (OTV) in 66% and 92% of cases, respectively. Median PTV was 15.77 ml (range, 805-3,604 ml). The data support the practical feasibility of IMRT in adjuvant treatment in

Comparison of mucous and cutaneous toxicity of IMRT and of conventional radiotherapy associated with cetuximab

International Nuclear Information System (INIS)

Kreps, S.; Tamby, E.; Dessard Diana, B.; Berges, O.; Botti, M.; Deberne, M.; Henni, M.; Durdux, C.; Housset, M.; Giraud, P.

2011-01-01

The authors report a retrospective assessment of acute, cutaneous and mucous toxicity resulting from an association of cetuximab and conventional conformational radiotherapy, and from an intensity-modulated conformational radiotherapy (IMRT). Seven patients presenting nasopharyngeal, oropharyngeal or hypopharyngeal tumours have been irradiated with intensity modulation, and seven without. It appears that the association of cetuximab and radiotherapy is not well tolerated and requires a close monitoring. Intensity-modulated radiotherapy allows a significant reduction of dose and of toxicity. However, mucous toxicity remains significant. Short communication

The outcome of the postoperative radiotherapy of autonomic nerve preserving operation for lower rectal cancer

International Nuclear Information System (INIS)

Takahashi, Keiichi; Mori, Takeo; Yasuno, Masamichi

1997-01-01

It is unclear whether adjuvant radiotherapy before or after surgery is effective for locally advanced, resectable lower rectal cancer. This study consists of a prospective randomized trial of postoperative radiotherapy for locally advanced curatively resected lower rectal carcinoma. We divided patients into two groups, one with postoperative 50 Gy radiation therapy to pelvic wall (N=64), and the other with no radiation therapy (N=46). The 5 year disease-free rate was 61.8% in the radiation group and 70.6% in the no radiation group. There was statistically no significant difference between these two groups. The local recurrence rate was 2.7% (radiation therapy group: 1.6%, no radiation therapy group: 4.3%). This local recurrence rate was very low. These results made us suspect that postoperative radiation therapy was not always necessary to prevent local recurrence. Postoperative complications had a higher incidence in the radiation therapy group than in the no-radiation therapy group. In the radiation therapy group, 35.5% of the patients suffered from diarrhea or frequent defecation, and 10.8% from severe abdominal pain. We operated on 4 cases of radiation-induced ileal stenosis and ileus. Postoperative radiation therapy did not help prevent local recurrence even though many complications resulted. (author)

MRI before and after external beam intensity-modulated radiotherapy of patients with prostate cancer: The feasibility of monitoring of radiation-induced tissue changes using a dynamic contrast-enhanced inversion-prepared dual-contrast gradient echo sequence

International Nuclear Information System (INIS)

Franiel, Tobias; Luedemann, Lutz; Taupitz, Matthias; Boehmer, Dirk; Beyersdorff, Dirk

2009-01-01

Purpose: To identify and quantify suitable pharmacokinetic MRI parameters for monitoring tissue changes after external beam intensity-modulated radiotherapy of prostate cancer. Material and methods: Six patients with biopsy-proven prostate cancer (initial PSA, 6.0-81.4 ng/ml) underwent MRI at 1.5 T using a combined endorectal/body phased-array coil and a dynamic contrast-enhanced inversion-prepared dual-contrast gradient echo sequence (T1/T2*w; 1.65 s temporal resolution). MRI was performed before and immediately after radiotherapy, at 3 months and at 1 year. Perfusion, blood volume, mean transit time, delay, dispersion, interstitial volume, and extraction coefficient were calculated in prostate cancer and normal prostate for all four time points using a sequential 3-compartment model. Results: Prostate cancer and normal prostate tissue showed a statistically significant decrease in perfusion (p = 0.006, p = 0.001) and increase in extraction coefficient (p = 0.004, p 3 min, p = 0.028) and a smaller extraction coefficient (0.42 vs. 0.64, p = 0.028). Conclusions: Two pharmacokinetic parameters, perfusion and extraction coefficient, appear to be suitable candidates for monitoring the response to percutaneous intensity-modulated radiotherapy of prostate cancer.

Postoperative radiotherapy after laser surgery with or without chemotherapy in head and neck evolved cancers

International Nuclear Information System (INIS)

Ryll, L.; Pradier, O.; Nitsche, M.; Christiansen, H.; Hess, C.

2007-01-01

We compared concurrent combination chemoradiotherapy and adjuvant radiotherapy after laser surgery in patients with stage 3/4 non metastatic squamous cell head and neck cancer. Combination chemotherapy and concurrent irradiation after laser surgery was not superior to surgery and postoperative radiotherapy for resectable advanced squamous cell head and neck cancer. However, the collective is small, and the follow-up to short to conclude. (authors)

Urethra sparing – potential of combined Nickel–Titanium stent and intensity modulated radiation therapy in prostate cancer

International Nuclear Information System (INIS)

Thomsen, Jakob Borup; Arp, Dennis Tideman; Carl, Jesper

2012-01-01

Background and purpose: To investigate a novel method for sparing urethra in external beam radiotherapy of prostate cancer and to evaluate the efficacy of such a treatment in terms of tumour control using a mathematical model. Materials and methods: This theoretical study includes 20 patients previously treated for prostate cancer using external beam radiotherapy. All patients had a Nickel–Titanium (Ni–Ti) stent inserted into the prostate part of urethra. The stent has been used during the treatment course as an internal marker for patient positioning prior to treatment. In this study the stent is used for delineating urethra while intensity modulated radiotherapy was used for lowering dose to urethra. Evaluation of the dose plans were performed using a tumour control probability model based on the concept of uniform equivalent dose. Results: The feasibility of the urethra dose reduction method is validated and a reduction of about 17% is shown to be possible. Calculations suggest a nearly preserved tumour control probability. Conclusions: A new concept for urethra dose reduction is presented. The method relies on the use of a Ni–Ti stent as a fiducial marker combined with intensity modulated radiotherapy. Theoretical calculations suggest preserved tumour control.

Implementation of an image guided intensity-modulated protocol for post-prostatectomy radiotherapy: planning data and acute toxicity outcomes.

Science.gov (United States)

Chua, Benjamin; Min, Myo; Wood, Maree; Edwards, Sarah; Hoffmann, Matthew; Greenham, Stuart; Kovendy, Andrew; McKay, Michael J; Shakespeare, Thomas P

2013-08-01

There is substantial interest in implementation of image-guided intensity-modulated radiotherapy (IG-IMRT) in the post-prostatectomy setting. We describe our implementation of IG-IMRT, and examine how often published organ-at-risk (OAR) constraints were met. Furthermore, we evaluate the incidence of acute genitourinary and gastrointestinal toxicities when patients were treated according to our protocol. Patients were eligible if they received post-prostatectomy radiotherapy (PPRT). Planning data were collected prospectively, and toxicity assessments were collected before, during and after treatment. Seventy-five eligible patients received either 64 Gy (19%) or 66 Gy (81%) in a single phase to the prostate bed. Suggested rectal dose-constraints of V40Gy < 60% and V60Gy < 40% were met in 64 (85%) and 75 (100%) patients, respectively. IMRT-specific rectal dose-constraints of V40Gy < 35% and V65Gy < 17% were achieved in 5 (7%) and 57 (76%) of patients. Bladder dose-constraint (V50Gy < 50%) was met in 58 (77%) patients. Two patients (3%) experienced new grade 3 genitourinary toxicity and one patient (1%) experienced new grade 3 gastroinestinal toxicity. All grade 3 toxicities had improved by 3-month review. Overall deterioration in urinary and gastrointestinal symptoms occurred in 33 (44%) and 35 (47%) of patients respectively. We report on our implementation of PPRT which takes into account nationally adopted guidelines, with a margin reduction supported by use of daily image guidance. Non-IMRT OAR constraints were met in most cases. IMRT-specific constraints were less often achieved despite margin reductions, suggesting the need for review of guidelines. Severe toxicity was rare, and most patients did not experience deterioration in urinary or bowel function attributable to radiotherapy. © 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.

Implementation of an image guided intensity-modulated protocol for post-prostatectomy radiotherapy: planning data and acute toxicity outcomes

International Nuclear Information System (INIS)

Chua, Benjamin; Min, Myo; Wood, Maree; Edwards, Sarah; Hoffmann, Matthew; Greenham, Stuart; Kovendy, Andrew; McKay, Michael J.; Shakespeare, Thomas P.

2013-01-01

There is substantial interest in implementation of image-guided intensity-modulated radiotherapy (IG-IMRT) in the post-prostatectomy setting. We describe our implementation of IG-IMRT, and examine how often published organ-at-risk (OAR) constraints were met. Furthermore, we evaluate the incidence of acute genitourinary and gastrointestinal toxicities when patients were treated according to our protocol. Patients were eligible if they received post-prostatectomy radiotherapy (PPRT). Planning data were collected prospectively, and toxicity assessments were collected before, during and after treatment. Seventy-five eligible patients received either 64Gy (19%) or 66Gy (81%) in a single phase to the prostate bed. Suggested rectal dose-constraints of V40Gy<60% and V60Gy<40% were met in 64 (85%) and 75 (100%) patients, respectively. IMRT-specific rectal dose-constraints of V40Gy<35% and V65Gy<17% were achieved in 5 (7%) and 57 (76%) of patients. Bladder dose-constraint (V50Gy<50%) was met in 58 (77%) patients. Two patients (3%) experienced new grade 3 genitourinary toxicity and one patient (1%) experienced new grade 3 gastrointestinal toxicity. All grade 3 toxicities had improved by 3-month review. Overall deterioration in urinary and gastrointestinal symptoms occurred in 33 (44%) and 35 (47%) of patients respectively. We report on our implementation of PPRT which takes into account nationally adopted guidelines, with a margin reduction supported by use of daily image guidance. Non-IMRT OAR constraints were met in most cases. IMRT-specific constraints were less often achieved despite margin reductions, suggesting the need for review of guidelines. Severe toxicity was rare, and most patients did not experience deterioration in urinary or bowel function attributable to radiotherapy.

Temporary organ displacement coupled with image-guided, intensity-modulated radiotherapy for paraspinal tumors

International Nuclear Information System (INIS)

Katsoulakis, Evangelia; Thornton, Raymond H; Yamada, Yoshiya; Solomon, Stephen B; Maybody, Majid; Housman, Douglas; Niyazov, Greg; Riaz, Nadeem; Lovelock, Michael; Spratt, Daniel E; Erinjeri, Joseph P

2013-01-01

To investigate the feasibility and dosimetric improvements of a novel technique to temporarily displace critical structures in the pelvis and abdomen from tumor during high-dose radiotherapy. Between 2010 and 2012, 11 patients received high-dose image-guided intensity-modulated radiotherapy with temporary organ displacement (TOD) at our institution. In all cases, imaging revealed tumor abutting critical structures. An all-purpose drainage catheter was introduced between the gross tumor volume (GTV) and critical organs at risk (OAR) and infused with normal saline (NS) containing 5-10% iohexol. Radiation planning was performed with the displaced OARs and positional reproducibility was confirmed with cone-beam CT (CBCT). Patients were treated within 36 hours of catheter placement. Radiation plans were re-optimized using pre-TOD OARs to the same prescription and dosimetrically compared with post-TOD plans. A two-tailed permutation test was performed on each dosimetric measure. The bowel/rectum was displaced in six patients and kidney in four patients. One patient was excluded due to poor visualization of the OAR; thus 10 patients were analyzed. A mean of 229 ml (range, 80–1000) of NS 5-10% iohexol infusion resulted in OAR mean displacement of 17.5 mm (range, 7–32). The median dose prescribed was 2400 cGy in one fraction (range, 2100–3000 in 3 fractions). The mean GTV D min and PTV D min pre- and post-bowel TOD IG-IMRT dosimetry significantly increased from 1473 cGy to 2086 cGy (p=0.015) and 714 cGy to 1214 cGy (p=0.021), respectively. TOD increased mean PTV D95 by 27.14% of prescription (p=0.014) while the PTV D05 decreased by 9.2% (p=0.011). TOD of the bowel resulted in a 39% decrease in mean bowel D max (p=0.008) confirmed by CBCT. TOD of the kidney significantly decreased mean kidney dose and D max by 25% (0.022). TOD was well tolerated, reproducible, and facilitated dose escalation to previously radioresistant tumors abutting critical structures while

Efficacy and Toxicity of Chemoradiotherapy Using Intensity-Modulated Radiotherapy for Unknown Primary of Head and Neck

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Sher, David J.; Balboni, Tracy A.; Haddad, Robert I.; Norris, Charles M.; Posner, Marshall R.; Wirth, Lori J.; Goguen, Laura A.; Annino, Donald; Tishler, Roy B.

2011-01-01

Purpose: No single standard treatment paradigm is available for head-and-neck squamous cell carcinoma of an unknown primary (HNCUP). Bilateral neck radiotherapy with mucosal axis irradiation is widely used, with or without chemotherapy and/or surgical resection. Intensity-modulated radiotherapy (IMRT) is a highly conformal method for delivering radiation that is becoming the standard of care and might reduce the long-term treatment-related sequelae. We report the Dana-Farber Cancer Institute experience with IMRT-based treatment for HNCUP. Patients and Materials: A retrospective study of all patients treated at the Dana-Farber Cancer Institute for HNCUP with IMRT between August 2004 and January 2009. The primary endpoint was overall survival; the secondary endpoints were locoregional and distant control, and acute and chronic toxicity. Results: A total of 24 patients with HNCUP were included. Of these patients, 22 had Stage N2 disease or greater. All patients underwent neck computed tomography, positron emission tomography-computed tomography, and examination under anesthesia with directed biopsies. Of the 24 patients, 22 received concurrent chemotherapy, and 7 (29%) also underwent induction chemotherapy. The median involved nodal dose was 70 Gy, and the median mucosal dose was 60 Gy. With a median follow-up of 2.1 years, the 2-year actuarial overall survival and locoregional control rate was 92% and 100%, respectively. Only 25% of the patients had Grade 2 xerostomia, although 11 patients (46%) required esophageal dilation for stricture. Conclusion: In a single-institution series, IMRT-based chemoradiotherapy for HNCUP was associated with superb overall survival and locoregional control. The xerostomia rates were promising, but the aggressive therapy was associated with significant rates of esophageal stenosis.

Prognostic Value of Cavernous Sinus Invasion in Patients with Nasopharyngeal Carcinoma Treated with Intensity-Modulated Radiotherapy.

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Jun-Fang Liao

Full Text Available To investigate the prognostic value of cavernoussinus invasion (CSI in patients with nasopharyngeal carcinoma (NPC treated with intensity-modulated radiotherapy (IMRT.Retrospective review of data from 1,087 patients with biopsy-proven, non-metastatic NPC. All patients were diagnosed using magnetic resonance imaging (MRI scans and received IMRT as the primary treatment.The incidence of cavernoussinus invasion in this cohort was 12.1%. In univariate analysis, 5-year overall survival (OS (70.6% vs. 88.5%, P < 0.001 and distant metastasis-free survival (DMFS (71.4% vs. 87.7%, P < 0.001, but not locoregional relapse-free survival (LRFS (93.9% vs. 93.7%, P = 0.341, were significantly different between patients with and without cavernoussinus invasion. In the T4 subgroup, the 5-year OS, DMFS, and LRFS of patients with and without cavernoussinus extension were 70.6% vs. 81.9% (P = 0.011, 71.4% vs. 84.1% (P = 0.011, and 91.2% vs. 89.7% (P = 0.501, respectively. In multivariate analysis, cavernoussinus invasion was an independent prognostic factor for poorer OS (HR = 1.782; P = 0.013 and DMFS (HR = 1.771; P = 0.016, but not LRFS (HR = 0.632; P = 0.294. In patients with lymph node metastasis, the DMFS rates of patients with and without cavernoussinus invasion were significantly different (P < 0.001. Preliminaryanalysis indicated that neoadjuvant chemotherapy led to better DMFS and OS in patients with cavernoussinus invasion than concurrent chemotherapy or radiotherapy alone; however, the differences were not significant.In the IMRT era, cavernoussinus invasion remains a prognostic factor for poor DMFS and OS in NPC, even in patients with T4 disease.

Intensity-modulated conformal radiotherapy in the anal canal cancer. Report of technological assessment. Updating of the 2006 report

International Nuclear Information System (INIS)

2015-07-01

As intensity-modulated conformal radiotherapy (IMCR) has already been technologically assessed in 2006 with a positive opinion for some treatments and a negative one for others, and as this technique displays some interesting properties for the treatment of pelvic cancers (optimisation of dose distribution, preservation of sane tissues, reduction of secondary effects during irradiation), this report proposes an assessment of clinical safety and efficiency of IMCR in the treatment of an anal canal cancer. After a discussion of generalities, of histological and epidemiological data, and of knowledge regarding treatment and follow-up of this cancer, the report presents the IMCR technique, some regulatory aspects, and its applications to the considered cancer. The methodology adopted for this assessment is then presented. Based on various studies and clinical results, the IMCR clinical safety and efficiency in the treatment of the anal canal cancer are discussed and assessed. Recommendations produced by different medical professional bodies are reported. Opinion of experts and a synthesis of stakeholders are then proposed

Haemostatis activity in rectal cancer patients exposed to preoperative radiotherapy: a clinical prospective cohort study

DEFF Research Database (Denmark)

Stender, Mogens T; Larsen, Torben B; Lundbye-Christensen, Søren

2009-01-01

To investigate whether markers of haemostasis activity increased during preoperative radiotherapy and whether postoperative marker levels were increased in irradiated rectal cancer patients when compared with nonirradiated rectal and colon cancer patients. In 45 rectal cancer patients, we measured...... plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complex, and D-dimer during radiotherapy. Postoperative levels of F1 + 2, thrombin-antithrombin complex, and D-dimer in irradiated patients were compared with postoperative levels in 123 nonirradiated colon and rectal cancer...... for activation of the haemostatic system during preoperative radiotherapy in patients with rectal cancer. Some evidence was provided for increased postoperative haemostatic activity among rectal cancer patients who received short-term high-intensity radiotherapy, when compared with patients who received long...

A comparison of morbidity following conformal versus intensity-modulated radiotherapy for urinary bladder cancer.

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Søndergaard, Jimmi; Holmberg, Mats; Jakobsen, Annette Ross; Agerbæk, Mads; Muren, Ludvig Paul; Høyer, Morten

2014-10-01

In radiotherapy (RT) of urinary bladder cancer, the use of intensity-modulated RT (IMRT) opens for sparing of considerable intestinal volumes. The purpose of the present study was to investigate the acute and late toxicities following either conformal RT (CRT) or IMRT for bladder cancer, and to correlate the toxicities to dose-volume parameters. The study included 116 consecutively treated patients with muscle-invasive bladder cancer who received either CRT (n = 66) or IMRT (n = 50) during 2007-2010. Acute side effects were retrospectively collected whereas late effects were assessed by a cross-sectional evaluation by telephone interview of 44 recurrence-free patients. Acute and late toxicities were scored according to the Common Terminology Criteria for Adverse Event (CTCAE) version 3.0. Acute diarrhoea grade ≥ 2 was more frequent in patients treated by CRT (56%) compared to IMRT (30%) (p = 0.008). Logistic regression analysis showed a correlation between acute diarrhoea and bowel cavity dose-volume parameters in the 10-50 Gy range. Severe late toxicity (grade ≥ 3) was recorded in 10% of the total cohort, with no statistical difference between the IMRT and CRT groups. Patients treated with IMRT for bladder cancer had significantly less acute diarrhoea compared to those treated with CRT, but there was no significant difference in late morbidity between the groups. The risk of acute diarrhoea was related to the volume of bowel irradiated.

Toxicity after post-prostatectomy image-guided intensity-modulated radiotherapy using Australian guidelines.

Science.gov (United States)

Chin, Stephen; Aherne, Noel J; Last, Andrew; Assareh, Hassan; Shakespeare, Thomas P

2017-12-01

We evaluated single institution toxicity outcomes after post-prostatectomy radiotherapy (PPRT) via image-guided intensity-modulated radiation therapy (IG-IMRT) with implanted fiducial markers following national eviQ guidelines, for which late toxicity outcomes have not been published. Prospectively collected toxicity data were retrospectively reviewed for 293 men who underwent 64-66 Gy IG-IMRT to the prostate bed between 2007 and 2015. Median follow-up after PPRT was 39 months. Baseline grade ≥2 genitourinary (GU), gastrointestinal (GI) and sexual toxicities were 20.5%, 2.7% and 43.7%, respectively, reflecting ongoing toxicity after radical prostatectomy. Incidence of new (compared to baseline) acute grade ≥2 GU and GI toxicity was 5.8% and 10.6%, respectively. New late grade ≥2 GU, GI and sexual toxicity occurred in 19.1%, 4.7% and 20.2%, respectively. However, many patients also experienced improvements in toxicities. For this reason, prevalence of grade ≥2 GU, GI and sexual toxicities 4 years after PPRT was similar to or lower than baseline (21.7%, 2.6% and 17.4%, respectively). There were no grade ≥4 toxicities. Post-prostatectomy IG-IMRT using Australian contouring guidelines appears to have tolerable acute and late toxicity. The 4-year prevalence of grade ≥2 GU and GI toxicity was virtually unchanged compared to baseline, and sexual toxicity improved over baseline. This should reassure radiation oncologists following these guidelines. Late toxicity rates of surgery and PPRT are higher than following definitive IG-IMRT, and this should be taken into account if patients are considering surgery and likely to require PPRT. © 2017 The Royal Australian and New Zealand College of Radiologists.

Improving bladder cancer treatment with radiotherapy using separate intensity modulated radiotherapy plans for boost and elective fields

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Van Rooijen, D.; Van de Kamer, J.; Hulshof, M.; Koning, C.; Bel, A. [Department of Radiation Oncology, Academic Medical Center, Amsterdam (Netherlands)

2010-06-01

The aim of this study is to investigate to what extent IMRT can decrease the dose to the organs at risk in bladder cancer treatment compared with conformal treatment while making separate treatment plans for the elective field and the boost. Special attention is paid to sparing small intestines. Twenty patients who were treated with the field-in-field technique (FiF) were re-planned with intensity modulated radiotherapy (IMRT) using five and seven beams, respectively. Separate treatment plans were made for the elective field (including the pelvic lymph nodes) and the boost, which enables position correction for bone and tumour separately. The prescribed dose was 40 Gy to the elective field and 55 or 60 Gy to the planning target volume (PTV). For bladder and rectum, V{sub 45}Gy and V{sub 55}Gy were compared, and for small intestines, V{sub 25}Gy and V{sub 40}Gy. The dose distribution with IMRT conformed better to the shape of the target. There was no significant difference between the techniques in dose to the healthy bladder. The median V{sub 40}Gy of the small intestines decreased from 114 to 66 cc (P = 0.001) with five beam IMRT, and to 55 cc (P = 0.001) with seven beam IMRT compared with FiF. V{sub 45}Gy for rectum decreased from 34.2% to 17.5% (P = 0.004) for both five and seven beam plans, while V{sub 55}Gy for rectum remained the same. With IMRT, a statistically significant dose decrease to the small intestines can be achieved while covering both tumour and elective PTV adequately.

Improving bladder cancer treatment with radiotherapy using separate intensity modulated radiotherapy plans for boost and elective fields

International Nuclear Information System (INIS)

Van Rooijen, D.; Van de Kamer, J.; Hulshof, M.; Koning, C.; Bel, A.

2010-01-01

The aim of this study is to investigate to what extent IMRT can decrease the dose to the organs at risk in bladder cancer treatment compared with conformal treatment while making separate treatment plans for the elective field and the boost. Special attention is paid to sparing small intestines. Twenty patients who were treated with the field-in-field technique (FiF) were re-planned with intensity modulated radiotherapy (IMRT) using five and seven beams, respectively. Separate treatment plans were made for the elective field (including the pelvic lymph nodes) and the boost, which enables position correction for bone and tumour separately. The prescribed dose was 40 Gy to the elective field and 55 or 60 Gy to the planning target volume (PTV). For bladder and rectum, V 45 Gy and V 55 Gy were compared, and for small intestines, V 25 Gy and V 40 Gy. The dose distribution with IMRT conformed better to the shape of the target. There was no significant difference between the techniques in dose to the healthy bladder. The median V 40 Gy of the small intestines decreased from 114 to 66 cc (P = 0.001) with five beam IMRT, and to 55 cc (P = 0.001) with seven beam IMRT compared with FiF. V 45 Gy for rectum decreased from 34.2% to 17.5% (P = 0.004) for both five and seven beam plans, while V 55 Gy for rectum remained the same. With IMRT, a statistically significant dose decrease to the small intestines can be achieved while covering both tumour and elective PTV adequately.

Improvement in toxicity in high risk prostate cancer patients treated with image-guided intensity-modulated radiotherapy compared to 3D conformal radiotherapy without daily image guidance

International Nuclear Information System (INIS)

Sveistrup, Joen; Rosenschöld, Per Munck af; Deasy, Joseph O; Oh, Jung Hun; Pommer, Tobias; Petersen, Peter Meidahl; Engelholm, Svend Aage

2014-01-01

Image-guided radiotherapy (IGRT) facilitates the delivery of a very precise radiation dose. In this study we compare the toxicity and biochemical progression-free survival between patients treated with daily image-guided intensity-modulated radiotherapy (IG-IMRT) and 3D conformal radiotherapy (3DCRT) without daily image guidance for high risk prostate cancer (PCa). A total of 503 high risk PCa patients treated with radiotherapy (RT) and endocrine treatment between 2000 and 2010 were retrospectively reviewed. 115 patients were treated with 3DCRT, and 388 patients were treated with IG-IMRT. 3DCRT patients were treated to 76 Gy and without daily image guidance and with 1–2 cm PTV margins. IG-IMRT patients were treated to 78 Gy based on daily image guidance of fiducial markers, and the PTV margins were 5–7 mm. Furthermore, the dose-volume constraints to both the rectum and bladder were changed with the introduction of IG-IMRT. The 2-year actuarial likelihood of developing grade > = 2 GI toxicity following RT was 57.3% in 3DCRT patients and 5.8% in IG-IMRT patients (p < 0.001). For GU toxicity the numbers were 41.8% and 29.7%, respectively (p = 0.011). On multivariate analysis, 3DCRT was associated with a significantly increased risk of developing grade > = 2 GI toxicity compared to IG-IMRT (p < 0.001, HR = 11.59 [CI: 6.67-20.14]). 3DCRT was also associated with an increased risk of developing GU toxicity compared to IG-IMRT. The 3-year actuarial biochemical progression-free survival probability was 86.0% for 3DCRT and 90.3% for IG-IMRT (p = 0.386). On multivariate analysis there was no difference in biochemical progression-free survival between 3DCRT and IG-IMRT. The difference in toxicity can be attributed to the combination of the IMRT technique with reduced dose to organs-at-risk, daily image guidance and margin reduction

Outcome of postoperative radiotherapy following radical prostatectomy: a single institutional experience

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Lee, Sea Won; Chung, Mi Joo; Jeong, Song Mi; Kim, Sung Hwan; Lee, Jong Hoon [Dept.of Radiation Oncology, St. Vincent' s Hospital, The Catholic University of Korea College of Medicine, Suwon (Korea, Republic of); Hwang, Tae Kon; Hong, Sung Hoo; Lee, Ji Youl; Jang, Hong Seok [Seoul St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Yoon, Sei Chul [Dept.of Radiation Oncology, Bucheon St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Bucheon (Korea, Republic of)

2014-09-15

This single institutional study is aimed to observe the outcome of patients who received postoperative radiotherapy after radical prostatectomy. A total of 59 men with histologically identified prostate adenocarcinoma who had received postoperative radiation after radical prostatectomy from August 2005 to July 2011 in Seoul St. Mary's Hospital of the Catholic University of Korea, was included. They received 45-50 Gy to the pelvis and boost on the prostate bed was given up to total dose of 63-72 Gy (median, 64.8 Gy) in conventional fractionation. The proportion of patients given hormonal therapy and the pattern in which it was given were analyzed. Primary endpoint was biochemical relapse-free survival (bRFS) after radiotherapy completion. Secondary endpoint was overall survival (OS). Biochemical relapse was defined as a prostate-specific antigen level above 0.2 ng/mL. After median follow-up of 53 months (range, 0 to 104 months), the 5-year bRFS of all patients was estimated 80.4%. The 5-year OS was estimated 96.6%. Patients who were given androgen deprivation therapy had a 5-year bRFS of 95.1% while the ones who were not given any had that of 40.0% (p < 0.01). However, the statistical significance in survival difference did not persist in multivariate analysis. The 3-year actuarial grade 3 chronic toxicity was 1.7% and no grade 3 acute toxicity was observed. The biochemical and toxicity outcome of post-radical prostatectomy radiotherapy in our institution is favorable and comparable to those of other studies.

Performance evaluation of an algorithm for fast optimization of beam weights in anatomy-based intensity modulated radiotherapy

International Nuclear Information System (INIS)

Ranganathan, Vaitheeswaran; Sathiya Narayanan, V.K.; Bhangle, Janhavi R.; Gupta, Kamlesh K.; Basu, Sumit; Maiya, Vikram; Joseph, Jolly; Nirhali, Amit

2010-01-01

This study aims to evaluate the performance of a new algorithm for optimization of beam weights in anatomy-based intensity modulated radiotherapy (IMRT). The algorithm uses a numerical technique called Gaussian-Elimination that derives the optimum beam weights in an exact or non-iterative way. The distinct feature of the algorithm is that it takes only fraction of a second to optimize the beam weights, irrespective of the complexity of the given case. The algorithm has been implemented using MATLAB with a Graphical User Interface (GUI) option for convenient specification of dose constraints and penalties to different structures. We have tested the numerical and clinical capabilities of the proposed algorithm in several patient cases in comparison with KonRad inverse planning system. The comparative analysis shows that the algorithm can generate anatomy-based IMRT plans with about 50% reduction in number of MUs and 60% reduction in number of apertures, while producing dose distribution comparable to that of beamlet-based IMRT plans. Hence, it is clearly evident from the study that the proposed algorithm can be effectively used for clinical applications. (author)

Impact of intensity-modulated and image-guided radiotherapy on elderly patients undergoing chemoradiation for locally advanced head and neck cancer

International Nuclear Information System (INIS)

Nguyen, N.P.; Chi, A.; Vock, J.

2012-01-01

Purpose: In this work, the treatment tolerance of elderly patients (≥ 70 years) undergoing intensity-modulated radiotherapy (IMRT) and image-guided radiotherapy (IGRT) and chemotherapy for locally advanced head and neck cancer was assessed. Patients and methods: A retrospective review of 112 patients undergoing concurrent chemoradiation for locally advanced head and neck cancer was performed. Treatment toxicity, protocol violations, long-term complications, and survival were compared between 85 younger patients (< 70 years) and 27 older patients (≥ 70 years). Results: Grade 3-4 treatment toxicity was observed in 88.2% and 88.8% for younger and older patients, respectively. Mean weight loss and treatment break were 5.9 and 3.9 kg (p = 0.03) and 7.3 and 7.8 days (p = 0.8) for younger and older patients, respectively. Seven patients (8.2%) did not complete treatment in the younger group compared to 1 patient (3.7%) in the older group (p = 0.6). No significant differences in protocol violations and survival were found between the two groups. Conclusion: Compared to younger patients, elderly patients with locally advanced head and neck cancer tolerated chemoradiation with IMRT and IGRT well, and should not be denied curative treatment based solely on age. (orig.)

Propensity Score-based Comparison of Long-term Outcomes With 3-Dimensional Conformal Radiotherapy vs Intensity-Modulated Radiotherapy for Esophageal Cancer

International Nuclear Information System (INIS)

Lin, Steven H.; Wang Lu; Myles, Bevan; Thall, Peter F.; Hofstetter, Wayne L.; Swisher, Stephen G.; Ajani, Jaffer A.; Cox, James D.; Komaki, Ritsuko; Liao Zhongxing

2012-01-01

Purpose: Although 3-dimensional conformal radiotherapy (3D-CRT) is the worldwide standard for the treatment of esophageal cancer, intensity modulated radiotherapy (IMRT) improves dose conformality and reduces the radiation exposure to normal tissues. We hypothesized that the dosimetric advantages of IMRT should translate to substantive benefits in clinical outcomes compared with 3D-CRT. Methods and Materials: An analysis was performed of 676 nonrandomized patients (3D-CRT, n=413; IMRT, n=263) with stage Ib-IVa (American Joint Committee on Cancer 2002) esophageal cancers treated with chemoradiotherapy at a single institution from 1998-2008. An inverse probability of treatment weighting and inclusion of propensity score (treatment probability) as a covariate were used to compare overall survival time, interval to local failure, and interval to distant metastasis, while accounting for the effects of other clinically relevant covariates. The propensity scores were estimated using logistic regression analysis. Results: A fitted multivariate inverse probability weighted-adjusted Cox model showed that the overall survival time was significantly associated with several well-known prognostic factors, along with the treatment modality (IMRT vs 3D-CRT, hazard ratio 0.72, P<.001). Compared with IMRT, 3D-CRT patients had a significantly greater risk of dying (72.6% vs 52.9%, inverse probability of treatment weighting, log-rank test, P<.0001) and of locoregional recurrence (P=.0038). No difference was seen in cancer-specific mortality (Gray's test, P=.86) or distant metastasis (P=.99) between the 2 groups. An increased cumulative incidence of cardiac death was seen in the 3D-CRT group (P=.049), but most deaths were undocumented (5-year estimate, 11.7% in 3D-CRT vs 5.4% in IMRT group, Gray's test, P=.0029). Conclusions: Overall survival, locoregional control, and noncancer-related death were significantly better after IMRT than after 3D-CRT. Although these results need

Can dosimetric parameters predict acute hematologic toxicity in rectal cancer patients treated with intensity-modulated pelvic radiotherapy?

International Nuclear Information System (INIS)

Wan, Juefeng; Liu, Kaitai; Li, Kaixuan; Li, Guichao; Zhang, Zhen

2015-01-01

To identify dosimetric parameters associated with acute hematologic toxicity (HT) in rectal cancer patients undergoing concurrent chemotherapy and intensity-modulated pelvic radiotherapy. Ninety-three rectal cancer patients receiving concurrent capecitabine and pelvic intensity-modulated radiation therapy (IMRT) were analyzed. Pelvic bone marrow (PBM) was contoured for each patient and divided into three subsites: lumbosacral spine (LSS), ilium, and lower pelvis (LP). The volume of each site receiving 5–40 Gy (V 5, V10, V15, V20, V30, and V40, respectively) as well as patient baseline clinical characteristics was calculated. The endpoint for hematologic toxicity was grade ≥ 2 (HT2+) leukopenia, neutropenia, anemia or thrombocytopenia. Logistic regression was used to analyze correlation between dosimetric parameters and grade ≥ 2 hematologic toxicity. Twenty-four in ninety-three patients experienced grade ≥ 2 hematologic toxicity. Only the dosimetric parameter V40 of lumbosacral spine was correlated with grade ≥ 2 hematologic toxicity. Increased pelvic lumbosacral spine V40 (LSS-V40) was associated with an increased grade ≥ 2 hematologic toxicity (p = 0.041). Patients with LSS-V40 ≥ 60 % had higher rates of grade ≥ 2 hematologic toxicity than did patients with lumbosacral spine V40 < 60 % (38.3 %, 18/47 vs.13 %, 6/46, p =0.005). On univariate and multivariate logistic regression analysis, lumbosacral spine V40 and gender was also the variable associated with grade ≥ 2 hematologic toxicity. Female patients were observed more likely to have grade ≥ 2 hematologic toxicity than male ones (46.9 %, 15/32 vs 14.8 %, 9/61, p =0.001). Lumbosacral spine -V40 was associated with clinically significant grade ≥ 2 hematologic toxicity. Keeping the lumbosacral spine -V40 < 60 % was associated with a 13 % risk of grade ≥ 2 hematologic toxicity in rectal cancer patients undergoing concurrent chemoradiotherapy

Interobserver Delineation variation using CT versus combined CT + MRI in intensity- modulated radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Villeirs, G.M.; Verstraete, K.L.; Vaerenbergh, K. van; Vakaet, L.; Bral, S.; Claus, F.; Neve, W.J. de; Meerleer, G.O. de

2005-01-01

Purpose: to quantify interobserver variation of prostate and seminal vesicle delineations using CT only versus CT + MRI in consensus reading with a radiologist. Material and methods: the prostate and seminal vesicles of 13 patients treated with intensity-modulated radiotherapy for prostatic adenocarcinoma were retrospectively delineated by three radiation oncologists on CT only and on CT + MRI in consensus reading with a radiologist. The volumes and margin positions were calculated and intermodality and interobserver variations were assessed for the clinical target volume (CTV), seminal vesicles, prostate and three prostatic subdivisions (apical, middle and basal third). Results: using CT + MRI as compared to CT alone, the mean CTV, prostate and seminal vesicle volumes significantly decreased by 6.54%, 5.21% and 10.47%, respectively. More importantly, their standard deviations significantly decreased by 63.06%, 62.65% and 44.83%, respectively. The highest level of variation was found at the prostatic apex, followed by the prostatic base and seminal vesicles. Conclusion: addition of MRI to CT in consensus reading with a radiologist results in a moderate decrease of the CTV, but an important decrease of the interobserver delineation variation, especially at the prostatic apex. (orig.)

Role of postoperative radiotherapy in the management of malignant pleural mesothelioma. A propensity score matching of the SEER database

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Abdel-Rahman, Omar [Ain Shams University, Clinical Oncology department, Faculty of medicine, Cairo (Egypt)

2017-04-15

This study assessed the prognostic impact of postoperative radiotherapy in patients with surgically resected malignant pleural mesothelioma (MPM). MPM patients diagnosed between 2000 and 2013 were identified from the SEER (Surveillance, Epidemiology, and End Results) database. A propensity-matched analysis was performed considering baseline characteristics (age, gender, race, histology, TNM stage, and type of surgery). A total of 2166 patients were identified. The median age was 60 years (range 25-85 years), and 469 patients received postoperative radiotherapy. Both before and after propensity score matching, overall survival (P < 0.0001 and P = 0.012, respectively) was better in the postoperative radiotherapy group. When the overall survival was stratified by histology, postoperative radiotherapy did not improve the survival in sarcomatoid histology patients both before and after matching (P = 0.424 and P = 0.281, respectively). In multivariate analysis of the matched population, not receiving postoperative radiotherapy did not correlate with worse survival (hazard ratio: 1.175; P = 0.12). Factors associated with worse survival include sarcomatoid histology, nodal positivity, and age ≥70. Evidence from this analysis is insufficient on its own to routinely recommend postoperative radiotherapy for surgically resected MPM. However, large-scale prospective clinical trials are warranted to further evaluate this intervention in nonsarcomatoid histology. (orig.) [German] In der vorliegenden Studie wurde der prognostische Einfluss der postoperativen Strahlentherapie bei Patienten mit chirurgisch reseziertem malignem Pleuramesotheliom (MPM) untersucht. In der SEER-Datenbank (Surveillance, Epidemiology, and End Results) wurden Patienten ermittelt, bei denen zwischen 2000 und 2013 die Diagnose eines MPM gestellt worden war. Unter Beruecksichtigung der Ausgangsmerkmale (Alter, Geschlecht, Ethnizitaet, Histologie, TNM-Stadium und Art des chirurgischen Eingriffs) wurde eine

Symptom resolution, tumor control, and side effects following postoperative radiotherapy for pituitary macroadenomas

International Nuclear Information System (INIS)

Rush, Stephen; Cooper, Paul R.

1997-01-01

This study reports the outcome of 70 patients who were treated by a consistent treatment plan of surgery and postoperative radiotherapy (RT) for pituitary macroadenomas in the modern era [computed tomographic scan or magnetic resonance imaging (MRI), dopamine agonist therapy (DA) added as indicated, and immunohistochemical staining]. Sixty-two patients underwent transsphenoidal surgery (vs. transcranial surgery) and 61 received 45-Gy/25 fractions postoperatively (vs. other dose fractionation schemes). Twenty-four patients received DA for prolactin-secreting tumors. With a median follow-up of 8 years (range 2-15), 68 patients have experienced continuous control of their tumors. Most symptoms related to mass effect abated, while physiologic symptoms such as amenorrhea from markedly elevated prolactin levels tended to persist. Treatment-induced hypopituitarism occurred in 42% of the patients at risk. No patients in this series have died as a result of their pituitary tumor. No gross neuropsychologic dysfunction after treatment has been noted. While it is possible at this time with serial MRI to withhold postoperative RT and observe some patients who have had a 'gross total' resection of a macroadenoma, the therapeutic ratio for surgery and adjuvant radiotherapy for patients with nonfunctional tumors as well as select patients with secretory macroadenomas is favorable

Intensity-modulated whole pelvic radiotherapy in women with gynecologic malignancies

International Nuclear Information System (INIS)

Mundt, Arno J.; Lujan, Anthony E.; Rotmensch, Jacob; Waggoner, Steven E.; Yamada, S. Diane; Fleming, Gini; Roeske, John C.

2002-01-01

Purpose: To describe our initial clinical experience with intensity-modulated whole pelvic radiotherapy (IM-WPRT) in women with gynecologic malignancies. Methods and Materials: Between February 2000 and August 2001, 40 gynecology patients underwent IM-WPRT. After fabrication of customized immobilization, all patients underwent contrast-enhanced CT, and a clinical target volume was contoured consisting of the upper vagina, parametria, uterus (if present), and presacral and pelvic lymph node regions. The clinical target volume was expanded by 1 cm to create a planning target volume (PTV). Using commercially available software, 7- or 9-field, 6-MV, coplanar IM-WPRT plans were generated for all patients. The worst acute gastrointestinal and genitourinary toxicity during treatment was scored on a 4-point scale: 0, none; 1, mild, no medications required; 2, moderate, medications required; and 3, severe, treatment breaks or cessation, hospitalization. As a comparison, acute toxicities in 35 previously treated conventional WPRT patients were analyzed. No significant differences were noted in the clinicopathologic and treatment factors between the two groups. Results: IM-WPRT plans provided excellent PTV coverage, with considerable sparing of the surrounding normal tissues. On average, 98.1% of the PTV received the prescription dose. The average percentage of the PTV receiving 110% and 115% of the prescription dose was 9.8% and 0.2%, respectively. IM-WPRT was well tolerated, with no patient developing Grade 3 toxicity. Grade 2 acute gastrointestinal toxicity was less common in the IM-WPRT group (60 vs. 91%, p=0.002) than in the conventional WPRT group. Moreover, the percentage of IM-WPRT and WPRT patients requiring no or only infrequent antidiarrheal medications was 75% and 34%, respectively (p=0.001). Although less Grade 2 genitourinary toxicity was seen in the IM-WPRT group (10% vs. 20%), this difference was not statistically significant (p=0.22). Conclusion: IM-WPRT is a

Intensity-modulated radiotherapy (IMRT) and conventional three-dimensional conformal radiotherapy for high-grade gliomas: Does IMRT increase the integral dose to normal brain?

International Nuclear Information System (INIS)

Hermanto, Ulrich; Frija, Erik K.; Lii, MingFwu J.; Chang, Eric L.; Mahajan, Anita; Woo, Shiao Y.

2007-01-01

Purpose: To determine whether intensity-modulated radiotherapy (IMRT) treatment increases the total integral dose of nontarget tissue relative to the conventional three-dimensional conformal radiotherapy (3D-CRT) technique for high-grade gliomas. Methods and Materials: Twenty patients treated with 3D-CRT for glioblastoma multiforme were selected for a comparative dosimetric evaluation with IMRT. Original target volumes, organs at risk (OAR), and dose-volume constraints were used for replanning with IMRT. Predicted isodose distributions, cumulative dose-volume histograms of target volumes and OAR, normal tissue integral dose, target coverage, dose conformity, and normal tissue sparing with 3D-CRT and IMRT planning were compared. Statistical analyses were performed to determine differences. Results: In all 20 patients, IMRT maintained equivalent target coverage, improved target conformity (conformity index [CI] 95% 1.52 vs. 1.38, p mean by 19.8% and D max by 10.7%), optic chiasm (D mean by 25.3% and D max by 22.6%), right optic nerve (D mean by 37.3% and D max by 28.5%), and left optic nerve (D mean by 40.6% and D max by 36.7%), p ≤ 0.01. This was achieved without increasing the total nontarget integral dose by greater than 0.5%. Overall, total integral dose was reduced by 7-10% with IMRT, p < 0.001, without significantly increasing the 0.5-5 Gy low-dose volume. Conclusions: These results indicate that IMRT treatment for high-grade gliomas allows for improved target conformity, better critical tissue sparing, and importantly does so without increasing integral dose and the volume of normal tissue exposed to low doses of radiation

Cost of New Technologies in Prostate Cancer Treatment: Systematic Review of Costs and Cost Effectiveness of Robotic-assisted Laparoscopic Prostatectomy, Intensity-modulated Radiotherapy, and Proton Beam Therapy.

Science.gov (United States)

Schroeck, Florian Rudolf; Jacobs, Bruce L; Bhayani, Sam B; Nguyen, Paul L; Penson, David; Hu, Jim

2017-11-01

Some of the high costs of robot-assisted radical prostatectomy (RARP), intensity-modulated radiotherapy (IMRT), and proton beam therapy may be offset by better outcomes or less resource use during the treatment episode. To systematically review the literature to identify the key economic trade-offs implicit in a particular treatment choice for prostate cancer. We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement and protocol. We searched Medline, Embase, and Web of Science for articles published between January 2001 and July 2016, which compared the treatment costs of RARP, IMRT, or proton beam therapy to the standard treatment. We identified 37, nine, and three studies, respectively. RARP is costlier than radical retropubic prostatectomy for hospitals and payers. However, RARP has the potential for a moderate cost advantage for payers and society over a longer time horizon when optimal cancer and quality-of-life outcomes are achieved. IMRT is more expensive from a payer's perspective compared with three-dimensional conformal radiotherapy, but also more cost effective when defined by an incremental cost effectiveness ratio new versus traditional technologies is costlier. However, given the low quality of evidence and the inconsistencies across studies, the precise difference in costs remains unclear. Attempts to estimate whether this increased cost is worth the expense are hampered by the uncertainty surrounding improvements in outcomes, such as cancer control and side effects of treatment. If the new technologies can consistently achieve better outcomes, then they may be cost effective. We review the cost and cost effectiveness of robot-assisted radical prostatectomy, intensity-modulated radiotherapy, and proton beam therapy in prostate cancer treatment. These technologies are costlier than their traditional counterparts. It remains unclear whether their use is associated

Evaluation of detector array technology for the verification of advanced intensity-modulated radiotherapy

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Hussien, Mohammad

Purpose: Quality assurance (QA) for intensity modulated radiotherapy (IMRT) has evolved substantially. In recent years, various ionization chamber or diode detector arrays have become commercially available, allowing pre-treatment absolute dose verification with near real-time results. This has led to a wide uptake of this technology to replace point dose and film dosimetry and to facilitate QA streamlining. However, arrays are limited by their spatial resolution giving rise to concerns about their response to clinically relevant deviations. The common factor in all commercial array systems is the reliance on the gamma index (γ) method to provide the quantitative evaluation of the measured dose distribution against the Treatment Planning System (TPS) calculated dose distribution. The mathematical definition of the gamma index presents computational challenges that can cause a variation in the calculation in different systems. The purpose of this thesis was to evaluate the suitability of detector array systems, combined with their implementation of the gamma index, in the verification and dosimetry audit of advanced IMRT. Method: The response of various commercial detector array systems (Delta4®, ArcCHECK®, and the PTW 2D-Array seven29™ and OCTAVIUS II™ phantom combination, Gafchromic® EBT2 and composite EPID measurements) to simulated deliberate changes in clinical IMRT and VMAT plans was evaluated. The variability of the gamma index calculation in the different systems was also evaluated by comparing against a bespoke Matlab-based gamma index analysis software. A novel methodology for using a commercial detector array in a dosimetry audit of rotational radiotherapy was then developed. Comparison was made between measurements using the detector array and those performed using ionization chambers, alanine and radiochromic film. The methodology was developed as part of the development of a national audit of rotational radiotherapy. Ten cancer centres were

Intensity-modulated radiotherapy plus nimotuzumab with or without concurrent chemotherapy for patients with locally advanced nasopharyngeal carcinoma

Directory of Open Access Journals (Sweden)

Huang JF

2017-12-01

Full Text Available Jianfeng Huang,1,* Qinzhou Zou,1,* Danqi Qian,1 Leyuan Zhou,1 Bo Yang,1 Jianjun Chu,1 Qingfeng Pang,2 Kewei Wang,2 Fuzheng Zhang1 1Department of Radiation Oncology, Affiliated Hospital of Jiangnan University, 2Department of Epidemiology, Wuxi Medical School of Jiangnan University, Wuxi, Jiangsu, People’s Republic of China *These authors contributed equally to this work Objective: This study aimed to evaluate the safety and efficacy of intensity-modulated radiotherapy (IMRT plus nimotuzumab with or without concurrent chemotherapy (CCT for patients with locally advanced nasopharyngeal carcinoma (LA-NPC. Patients and methods: A total of 50 newly diagnosed patients with LA-NPC treated at the Affiliated Hospital of Jiangnan University between November 2011 and January 2017 were retrospectively analyzed. All patients received the combined treatment modality of nimotuzumab plus IMRT. Nimotuzumab was administered concurrently with IMRT at a weekly dose of 200 mg. Neoadjuvant, concurrent or adjuvant chemotherapy with the doublet regimen of taxanes (docetaxel or paclitaxel plus platinum (cisplatin or nedaplatin were administered. Among the 50 patients, 43 (86.0% received ≥6 cycles of nimotuzumab (median 7 cycles, range 2–14 cycles and 29 (58.0% received two cycles of CCT with docetaxel plus nedaplatin. Results: With a median follow-up of 28.0 months, the 2-year progression-free survival (PFS and overall survival were 83.29% (95% confidence interval [CI]: 67.93%–91.72% and 97.67% (95% CI: 84.62%–99.67%, respectively. Both univariate and multivariate analyses revealed that cycles of nimotuzumab were significantly associated with PFS. Patients who received ≥6 cycles of nimotuzumab showed a better PFS than those receiving <6 cycles (P=0.006, whereas the addition of CCT failed to improve PFS. Oral mucositis was the most common adverse event, which was recorded as grade 3–4 in 18 (36.0% patients. Besides, two (4.0% patients experienced

Evolution of treatment for nasopharyngeal cancer – Success and setback in the intensity-modulated radiotherapy era

International Nuclear Information System (INIS)

Lee, Anne W.M.; Ng, Wai Tong; Chan, Lucy L.K.; Hung, Wai Man; Chan, Connie C.C.; Sze, Henry C.K.; Chan, Oscar S.H.; Chang, Amy T.Y.; Yeung, Rebecca M.W.

2014-01-01

Background and purpose: To assess the therapeutic gains and setbacks as we evolved from the 2-dimensional radiotherapy (2DRT) to conformal 3-dimensional (3DRT) and to intensity-modulated (IMRT) era. Materials and methods: 1593 consecutive patients from 1994 to 2010 were retrospectively analyzed. Evolving changes in the different era included advances in staging investigation, radiotherapy technique, dose escalation, and use of chemotherapy. Results: The 3DRT era achieved significant improvement in local failure-free rate (L-FFR), disease-specific survival (DSS) and overall survival (OS). Neurological damage and bone/soft tissue necrosis were significantly reduced. However, the improvement in distant failure-free rate (D-FFR) was insignificant, and more hearing impairment occurred due to chemotherapy. Significantly higher D-FFR was achieved in the IMRT era, but L-FFR did not show further improvement. 5-Year DSS increased from 78% in the 2DRT, to 81% in the 3DRT, and 85% in the IMRT era, while the corresponding neurological toxicity rate decreased from 7.4% to 3.5% and 1.8%. Conclusions: Significant improvement in survival and reduction of serious toxicity was achieved as we evolved from 2DRT to 3DRT and IMRT era; the therapeutic ratio for all T-categories improved with more conformal techniques. Improvements in tumor control were attributed not only to advances in RT technique, but also to better imaging and increasing use of potent chemotherapy. However, it should also be noted that hearing impairment significantly increased due to chemotherapy, L-FFR reached a plateau in the 3DRT era, and it is worrisome that the result for T4 remained unsatisfactory. Besides exploring for more potent chemotherapy and innovative methods, the guideline on dose constraint should be re-visited to optimize the therapeutic ratio

Grading xerostomia by physicians or by patients after intensity-modulated radiotherapy of head-and-neck cancer

International Nuclear Information System (INIS)

Meirovitz, Amichay; Murdoch-Kinch, Carol Anne; Schipper, Mathew; Pan, Charlie; Eisbruch, Avraham

2006-01-01

Purpose: To assess observer-based vs. patient self-reported scoring of xerostomia after intensity-modulated radiotherapy (IMRT) of head-and-neck (HN) cancer. Methods: A total of 38 patients who had received IMRT for HN cancer underwent xerostomia evaluations 6 to 24 months after completion of therapy using three methods each time: (1) Grading by 3 observers according to the Radiotherapy Oncology Group/European Organization for Research and Therapy of Cancer (RTOG/EORTC) system; (2) patient self-reported validated xerostomia questionnaire (XQ); and (3) major salivary gland flow measurements. Results: The interobserver agreement regarding the RTOG/EORTC grades was moderate: κ-coefficient 0.54 (95% CI = 0.31-0.76). The correlations between the average RTOG/EORTC grades and the salivary flow rates were not statistically significant. A trend for significant correlation was observed between these grades and the percent (relative to the pretherapy) nonstimulated salivary flow rates (p = 0.07), but not with the percent stimulated flow rates. Better correlations were found between grading made more than the median time (15 min) after the last liquid sipping and the nonstimulated (but not the stimulated) flows compared with grading made shortly after sipping. In contrast, significant correlations were found between the XQ scores and the nonstimulated (p < 0.005) and the stimulated (p < 0.005) salivary flow rates, as well as with the percentages of the corresponding pretherapy values (p = 0.002 and 0.038, respectively). No significant correlation was found between the RTOG/EORTC grades and the XQ scores. The observer-based grades underestimated the severity of xerostomia compared with the patient self-reported scores. Conclusions: Patient self-reported, rather than physician-assessed scores, should be the main end points in evaluating xerostomia

Photon energy-modulated radiotherapy: Monte Carlo simulation and treatment planning study

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Min; Kim, Jung-in; Heon Choi, Chang; Chie, Eui Kyu; Kim, Il Han; Ye, Sung-Joon [Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744, Korea and Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of) and Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of) and Department of Intelligent Convergence Systems, Seoul National University, Seoul, 151-742 (Korea, Republic of)

2012-03-15

Purpose: To demonstrate the feasibility of photon energy-modulated radiotherapy during beam-on time. Methods: A cylindrical device made of aluminum was conceptually proposed as an energy modulator. The frame of the device was connected with 20 tubes through which mercury could be injected or drained to adjust the thickness of mercury along the beam axis. In Monte Carlo (MC) simulations, a flattening filter of 6 or 10 MV linac was replaced with the device. The thickness of mercury inside the device varied from 0 to 40 mm at the field sizes of 5 x 5 cm{sup 2} (FS5), 10 x 10 cm{sup 2} (FS10), and 20 x 20 cm{sup 2} (FS20). At least 5 billion histories were followed for each simulation to create phase space files at 100 cm source to surface distance (SSD). In-water beam data were acquired by additional MC simulations using the above phase space files. A treatment planning system (TPS) was commissioned to generate a virtual machine using the MC-generated beam data. Intensity modulated radiation therapy (IMRT) plans for six clinical cases were generated using conventional 6 MV, 6 MV flattening filter free, and energy-modulated photon beams of the virtual machine. Results: As increasing the thickness of mercury, Percentage depth doses (PDD) of modulated 6 and 10 MV after the depth of dose maximum were continuously increased. The amount of PDD increase at the depth of 10 and 20 cm for modulated 6 MV was 4.8% and 5.2% at FS5, 3.9% and 5.0% at FS10 and 3.2%-4.9% at FS20 as increasing the thickness of mercury from 0 to 20 mm. The same for modulated 10 MV was 4.5% and 5.0% at FS5, 3.8% and 4.7% at FS10 and 4.1% and 4.8% at FS20 as increasing the thickness of mercury from 0 to 25 mm. The outputs of modulated 6 MV with 20 mm mercury and of modulated 10 MV with 25 mm mercury were reduced into 30%, and 56% of conventional linac, respectively. The energy-modulated IMRT plans had less integral doses than 6 MV IMRT or 6 MV flattening filter free plans for tumors located in the

Prognostic value and importance of surgery combined with postoperative radiotherapy for oral and oropharyngeal cancer

International Nuclear Information System (INIS)

Maciejewski, A.

2001-01-01

The aim of this paper is to evaluate the efficacy of surgery for patients with oral cavity or oropharyngeal cancer, and is impact on the final results of treatment combined with postoperative radiotherapy. Furthermore, predictive and prognostic value of clinical and histopatological postoperative factors were analysed, and estimation of clinical applicability of modified scale for risk of postoperative local and/or nodal recurrence according to Peters was checked. Material includes 218 cases of the advanced oral cavity or oropharyngeal cancer. All data were subdivided into 4 groups depending on treatment strategy. For the analysis of the treatment efficacy (overall and disease-free survival) many predictive and prognostic factors have been considered. Despite of multivariate logistic regression analysis of these factors, the risk of local recurrence was related to the results of combined treatment based on the modified numerical risk scale adapted from Peters. The risk value is the sum of scores given to individual prognostic factors. Time interval between surgery and radiotherapy (TI) and overall treatment time (TTT) have been accounted for the analysis. Generally; optimal results were noted in the group B, where surgery has been combined with postoperative radiotherapy. In case of surgery combined with preoperative radiotherapy (group E) 5-year DFS was 30%, and in the case when radiotherapy was delayed and applied when recurrence after primary surgery has occurred, the 5-year DFS was not higher than 20%. Macro- and microscopic surgical radicalism has been found one of the most important and significant prognostic factors. For positive margins (m+) 5-year DFS significantly decreases to about 20%. Surgical macro- and microradicalism has an important impact (p = 0.013) on the incidence of distant metastases. The scoring system for the recurrence was based on Peters scale. The sum of the risk scores (TRRI+n) for individual prognostic factors allow to allocate

Nasopharyngeal Carcinoma in Children: Comparison of Conventional and Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Laskar, Siddhartha; Bahl, Gaurav; Muckaden, MaryAnn; Pai, Suresh K.; Gupta, Tejpal; Banavali, Shripad; Arora, Brijesh; Sharma, Dayanand; Kurkure, Purna A.; Ramadwar, Mukta; Viswanathan, Seethalaxhmi; Rangarajan, Venkatesh; Qureshi, Sajid; Deshpande, Deepak D.; Shrivastava, Shyam K.; Dinshaw, Ketayun A.

2008-01-01

Purpose: To evaluate the efficacy of intensity-modulated radiotherapy (IMRT) in reducing the acute toxicities associated with conventional RT (CRT) in children with nasopharyngeal carcinoma. Patients and Methods: A total of 36 children with nonmetastatic nasopharyngeal carcinoma, treated at the Tata Memorial Hospital between June 2003 and December 2006, were included in this study. Of the 36 patients, 28 were boys and 8 were girls, with a median age of 14 years; 4 (11%) had Stage II and 10 (28%) Stage III disease at presentation. All patients had undifferentiated carcinoma and were treated with a combination of chemotherapy and RT. Of the 36 patients, 19 underwent IMRT and 17 underwent CRT. Results: After a median follow-up of 27 months, the 2-year locoregional control, disease-free, and overall survival rate was 76.5%, 60.6%, and 71.3%, respectively. A significant reduction in acute Grade 3 toxicities of the skin (p = 0.006), mucous membrane (p = 0.033), and pharynx (p = 0.035) was noted with the use of IMRT. The median time to the development of Grade 2 toxicity was delayed with IMRT (skin, 35 vs. 25 days, p = 0.016; mucous-membrane, 39 vs. 27 days, p = 0.002; and larynx, 50 vs. 28 days, p = 0.009). The duration of RT significantly influenced disease-free survival on multivariate analysis (RT duration >52 days, hazard ratio = 5.49, 95% confidence interval, 1.14-26.45, p = 0.034). The average mean dose to the first and second planning target volume was 71.8 Gy and 62.5 Gy with IMRT compared with 66.3 Gy (p = 0.001) and 64.4 Gy (p = 0.046) with CRT, respectively. Conclusion: The results of our study have shown that IMRT significantly reduces and delays the onset of acute toxicity, resulting in improved tolerance and treatment compliance for children with nasopharyngeal carcinoma. Also, IMRT provided superior target coverage and normal tissue sparing compared with CRT

Potential clinical predictors of outcome after postoperative radiotherapy of non-small cell lung cancer

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Buetof, R. [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiation Oncology, Dresden (Germany); Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, OncoRay National Center for Radiation Research in Oncology, Dresden (Germany); Kirchner, K.; Appold, S. [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiation Oncology, Dresden (Germany); Loeck, S. [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, OncoRay National Center for Radiation Research in Oncology, Dresden (Germany); Rolle, A. [Lungenfachklinik Coswig, Department of Thoracic and Vascular Surgery, Coswig (Germany); Hoeffken, G. [Lungenfachklinik Coswig, Department of Pneumology, Coswig (Germany); Krause, M.; Baumann, M. [Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, Department of Radiation Oncology, Dresden (Germany); Medical Faculty and University Hospital Carl Gustav Carus, Technische Universitaet Dresden, OncoRay National Center for Radiation Research in Oncology, Dresden (Germany); German Cancer Consortium (DKTK), Dresden (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany)

2014-03-15

The aim of this analysis was to investigate the impact of tumour-, treatment- and patient-related cofactors on local control and survival after postoperative adjuvant radiotherapy in patients with non-small cell lung cancer (NSCLC), with special focus on waiting and overall treatment times. For 100 NSCLC patients who had received postoperative radiotherapy, overall, relapse-free and metastases-free survival was retrospectively analysed using Kaplan-Meier methods. The impact of tumour-, treatment- and patient-related cofactors on treatment outcome was evaluated in uni- and multivariate Cox regression analysis. No statistically significant difference between the survival curves of the groups with a short versus a long time interval between surgery and radiotherapy could be shown in uni- or multivariate analysis. Multivariate analysis revealed a significant decrease in overall survival times for patients with prolonged overall radiotherapy treatment times exceeding 42 days (16 vs. 36 months) and for patients with radiation-induced pneumonitis (8 vs. 29 months). Radiation-induced pneumonitis and prolonged radiation treatment times significantly reduced overall survival after adjuvant radiotherapy in NSCLC patients. The negative impact of a longer radiotherapy treatment time could be shown for the first time in an adjuvant setting. The hypothesis of a negative impact of longer waiting times prior to commencement of adjuvant radiotherapy could not be confirmed. (orig.) [German] Das Ziel der vorliegenden Analyse war, den Einfluss von tumor-, patienten- und therapieabhaengigen Kofaktoren auf die lokoregionale Tumorkontrolle und das Ueberleben nach postoperativer adjuvanter Strahlentherapie bei Patienten mit einem nicht-kleinzelligen Bronchialkarzinom (NSCLC) zu untersuchen. Ein spezieller Fokus lag dabei auf der Wartezeit zwischen Operation und Beginn der Strahlentherapie sowie der Gesamtbehandlungszeit der Strahlentherapie. Fuer 100 Patienten, die eine postoperative

Utilization of intensity modulated beam radiotherapy (IMBXRT) to diminish dose to the parotid gland in head and neck cancer

International Nuclear Information System (INIS)

Shiao, W. Woo; Grant, Walter H.; Butler, E. Brian

1996-01-01

Purpose/Objective: To determine if intensity conformal modulated radiotherapy could diminish the radiation dose to the parotid gland in the treatment of primary head and neck cancer. Materials and Methods: The NOMOS Peacock treatment system was utilized in the planning and delivery of conformal radiotherapy for the following diseases: 1) an oropharyngeal cancer that extends from the soft palate to the tonsillar fossa without nodal disease, 2) laryngeal hypopharyngeal cancer without nodal disease, 3) and adenocystic carcinoma, that originated in the hard palate. Patients were treated to areas suspicious for microscopic disease (nodal disease in 1 and 2, perineural spread in 3) at 2 Gy per fraction for a tc of 50 Gy in five weeks. The primary disease was treated at 2.4 Gy per fraction for a total of 60 Gy over five weeks. The percent of the volume of each parotid gland receiving < 20 Gy, <25 Gy and <30 Gy retrospectively was determined for each of the above mentioned optimized plans. The patients were observed for the clinical development of xerostomia. Results: No patient developed clinically apparent xerostomia within one month of completion of radiotherapy. Conclusion: IMBXRT could reduce the volume to parotid glands receiving high radiation doses. Sparing of the parotid glands appear to be most easily accomplished when irradiating head and neck tumors that do not require regional nodal treatment. For head and neck cancer that requires nodal treatment it is possible to spare a significant portion of the parotid glands if the disease originates below the hyoid bone where the primary site is not in close proximity to the parotid glands. Objective salivary flow data are being obtained pre ar post treatment, to confirm the subjective impression of lack of clinical xerostomia. IMBXRT is potentially beneficial in decreasing the morbidity of xerostomia related to head and neck irradiation

Conformity Index and Homogeneity Index of the Postoperative Whole Breast Radiotherapy.

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Petrova, Deva; Smickovska, Snezana; Lazarevska, Emilija

2017-10-15

The treatment of breast cancer involves a multidisciplinary approach in which radiotherapy plays a key role. The conformity index and the homogeneity index are two analysis tools of a treatment plan using conformal radiotherapy. The purpose of this article is an analysis of these two parameters in the assessment of the treatment plans in 58 patients undergoing postoperative radiotherapy of the whole breast. All 58 patients participating in the study had a conservatively treated early-stage breast cancer. The treatment was performed using a standard regimen of fractionation in 25 fractions up to a total dose of 50 Gy. Dose-volume histograms were generated for both plans with and without segmental fields. Pair samples t-test was used. The technique with segmental fields allowed us more homogeneity distribution when compared to standard two tangential field techniques. The HI values were 1.08 ± 0.01 and 1.09 ± 0.01 for segment and technique with two tangential fields (p conformity and the homogeneity index are important tools in the analysis of the treatment plans during radiation therapy in patients with early-stage breast cancer. Adding segment fields in the administration of radiotherapy in patients with conservatively treated breast cancer can lead to improved dosage homogeneity and conformity.

3D-conformal-intensity modulated radiotherapy with compensators for head and neck cancer: clinical results of normal tissue sparing

Directory of Open Access Journals (Sweden)

Koscielny Sven

2006-06-01

Full Text Available Abstract Background To investigate the potential of parotic gland sparing of intensity modulated radiotherapy (3D-c-IMRT performed with metallic compensators for head and neck cancer in a clinical series by analysis of dose distributions and clinical measures. Materials and methods 39 patients with squamous cell cancer of the head and neck irradiated using 3D-c-IMRT were evaluable for dose distribution within PTVs and at one parotid gland and 38 patients for toxicity analysis. 10 patients were treated primarily, 29 postoperatively, 19 received concomittant cis-platin based chemotherapy, 20 3D-c-IMRT alone. Initially the dose distribution was calculated with Helax ® and photon fluence was modulated using metallic compensators made of tin-granulate (n = 22. Later the dose distribution was calculated with KonRad ® and fluence was modified by MCP 96 alloy compensators (n = 17. Gross tumor/tumor bed (PTV 1 was irradiated up to 60–70 Gy, [5 fractions/week, single fraction dose: 2.0–2.2 (simultaneously integrated boost], adjuvantly irradiated bilateral cervical lymph nodes (PTV 2 with 48–54 Gy [single dose: 1.5–1.8]. Toxicity was scored according the RTOG scale and patient-reported xerostomia questionnaire (XQ. Results Mean of the median doses at the parotid glands to be spared was 25.9 (16.3–46.8 Gy, for tin graulate 26 Gy, for MCP alloy 24.2 Gy. Tin-granulate compensators resulted in a median parotid dose above 26 Gy in 10/22, MCP 96 alloy in 0/17 patients. Following acute toxicities were seen (°0–2/3: xerostomia: 87%/13%, dysphagia: 84%/16%, mucositis: 89%/11%, dermatitis: 100%/0%. No grade 4 reaction was encountered. During therapy the XQ forms showed °0–2/3: 88%/12%. 6 months postRT chronic xerostomia °0–2/3 was observed in 85%/15% of patients, none with °4 xerostomia. Conclusion 3D-c-IMRT using metallic compensators along with inverse calculation algorithm achieves sufficient parotid gland sparing in virtually all advanced

Intensity-Modulated Radiotherapy Results in Significant Decrease in Clinical Toxicities Compared With Conventional Wedge-Based Breast Radiotherapy

International Nuclear Information System (INIS)

Harsolia, Asif; Kestin, Larry; Grills, Inga; Wallace, Michelle; Jolly, Shruti; Jones, Cortney; Lala, Moinaktar; Martinez, Alvaro; Schell, Scott; Vicini, Frank A.

2007-01-01

Purpose: We have previously demonstrated that intensity-modulated radiotherapy (IMRT) with a static multileaf collimator process results in a more homogenous dose distribution compared with conventional wedge-based whole breast irradiation (WBI). In the present analysis, we reviewed the acute and chronic toxicity of this IMRT approach compared with conventional wedge-based treatment. Methods and Materials: A total of 172 patients with Stage 0-IIB breast cancer were treated with lumpectomy followed by WBI. All patients underwent treatment planning computed tomography and received WBI (median dose, 45 Gy) followed by a boost to 61 Gy. Of the 172 patients, 93 (54%) were treated with IMRT, and the 79 patients (46%) treated with wedge-based RT in a consecutive fashion immediately before this cohort served as the control group. The median follow-up was 4.7 years. Results: A significant reduction in acute Grade 2 or worse dermatitis, edema, and hyperpigmentation was seen with IMRT compared with wedges. A trend was found toward reduced acute Grade 3 or greater dermatitis (6% vs. 1%, p = 0.09) in favor of IMRT. Chronic Grade 2 or worse breast edema was significantly reduced with IMRT compared with conventional wedges. No difference was found in cosmesis scores between the two groups. In patients with larger breasts (≥1,600 cm 3 , n = 64), IMRT resulted in reduced acute (Grade 2 or greater) breast edema (0% vs. 36%, p <0.001) and hyperpigmentation (3% vs. 41%, p 0.001) and chronic (Grade 2 or greater) long-term edema (3% vs. 30%, p 0.007). Conclusion: The use of IMRT in the treatment of the whole breast results in a significant decrease in acute dermatitis, edema, and hyperpigmentation and a reduction in the development of chronic breast edema compared with conventional wedge-based RT

Isocentric integration of intensity-modulated radiotherapy with electron fields improves field junction dose uniformity in postmastectomy radiotherapy.

Science.gov (United States)

Wright, Pauliina; Suilamo, Sami; Lindholm, Paula; Kulmala, Jarmo

2014-08-01

In postmastectomy radiotherapy (PMRT), the dose coverage of the planning target volume (PTV) with additional margins, including the chest wall, supraclavicular, interpectoral, internal mammary and axillar level I-III lymph nodes, is often compromised. Electron fields may improve the medial dose coverage while maintaining organ at risk (OAR) doses at an acceptable level, but at the cost of hot and cold spots at the electron and photon field junction. To improve PMRT dose coverage and uniformity, an isocentric technique combining tangential intensity-modulated (IM)RT fields with one medial electron field was implemented. For 10 postmastectomy patients isocentric IMRT with electron plans were created and compared with a standard electron/photon mix and a standard tangent technique. PTV dose uniformity was evaluated based on the tolerance range (TR), i.e. the ratio of the standard deviation to the mean dose, a dice similarity coefficient (DSC) and the 90% isodose coverage and the hot spot volumes. OAR and contralateral breast doses were also recorded. IMRT with electrons significantly improved the PTV dose homogeneity and conformity based on the TR and DSC values when compared with the standard electron/photon and tangent technique (p < 0.02). The 90% isodose coverage improved to 86% compared with 82% and 80% for the standard techniques (p < 0.02). Compared with the standard electron/photon mix, IMRT smoothed the dose gradient in the electron and photon field junction and the volumes receiving a dose of 110% or more were reduced by a third. For all three strategies, the OAR and contralateral breast doses were within clinically tolerable limits. Based on these results two-field IMRT combined with an electron field is a suitable strategy for PMRT.

Selection of the optimal radiotherapy technique for locally advanced hepatocellular carcinoma

International Nuclear Information System (INIS)

Lee, Ik-Jae; Seong, Jinsil; Koom, Woong-Sub; Kim, Yong-Bae; Jeon, Byeong-Chul; Kim, Joo-Ho; Han, Kwang-Hyub

2011-01-01

Various techniques are available for radiotherapy of hepatocellular carcinoma, including three-dimensional conformal radiotherapy, linac-based intensity-modulated radiotherapy and helical tomotherapy. The purpose of this study was to determine the optimal radiotherapy technique for hepatocellular carcinoma. Between 2006 and 2007, 12 patients underwent helical tomotherapy for locally advanced hepatocellular carcinoma. Helical tomotherapy computerized radiotherapy planning was compared with the best computerized radiotherapy planning for three-dimensional conformal radiotherapy and linac-based intensity-modulated radiotherapy for the delivery of 60 Gy in 30 fractions. Tumor coverage was assessed by conformity index, radical dose homogeneity index and moderated dose homogeneity index. Computerized radiotherapy planning was also compared according to the tumor location. Tumor coverage was shown to be significantly superior with helical tomotherapy as assessed by conformity index and moderated dose homogeneity index (P=0.002 and 0.03, respectively). Helical tomotherapy showed significantly lower irradiated liver volume at 40, 50 and 60 Gy (V40, V50 and V60, P=0.04, 0.03 and 0.01, respectively). On the contrary, the dose-volume of three-dimensional conformal radiotherapy at V20 was significantly smaller than those of linac-based intensity-modulated radiotherapy and helical tomotherapy in the remaining liver (P=0.03). Linac-based intensity-modulated radiotherapy showed better sparing of the stomach compared with helical tomotherapy in the case of separated lesions in both lobes (12.3 vs. 24.6 Gy). Helical tomotherapy showed the high dose-volume exposure to the left kidney due to helical delivery in the right lobe lesion. Helical tomotherapy achieved the best tumor coverage of the remaining normal liver. However, helical tomotherapy showed much exposure to the remaining liver at the lower dose region and left kidney. (author)

The study of treatment value of concurrent chemotherapy for patients with esophageal carcinoma received three-dimensional conformal radiotherapy or intensity modulated radiotherapy

International Nuclear Information System (INIS)

Wang Lan; Wang Jun; Han Chun; Zhang Jing; Li Xiaoning; Gao Chao

2011-01-01

Objective: To observe the acute side effects, local control rate and survival rate of concurrent chemoradiotherapy (CC) and radiotherapy alone (R) for patients with esophageal carcinoma. Methods: From June 2006 to February 2009, 209 patients with esophageal carcinoma were observed, 105 of them were treated with CC. Of all the patients, 117 received three-dimensional conformal radiotherapy, 92 received intensity modulated radiotherapy, the median prescription dose was 60 Gy. The regimen of LFP (5-FU, cisplatin and calcium folinate) was selected for this study, side effects, local control rate and survival rate were observed and subsets analysis were performed. Results: The overall follow-up rate was 99.0%,there were 99 and 44 patients whose follow-up time was more than 2 and 3 years, respectively;for the CC group, the data were 45 and 14, respectively; and for the R group, 54 and 30, respectively. The 1-, 2-, 3-year local control rates of CC group and R group were 88.1%, 69.2%, 66.2% and 81.0%, 64.0%, 54.9% (χ 2 =2.31, P=0.128), respectively. The 1-, 2-, 3-year overall survival rates of CC group and R group were 84.4%, 52.9%, 45.6% and 75.2%, 50.7%, 37.0%(χ 2 =1.57, P=0.210), respectively. Subset analysis indicated that for the patients of N 0 group and whose length of GTV >7 cm, the local control rate of CC was significantly higher than that of radiotherapy alone (χ 2 =5.11, 7.66; P=0.024, 0.006). For N 0 group, the survival rate of CC was higher than that of R alone. (χ 2 =5.07, P=0.024). The incidence of WBC, PLT and HGB reduction for the two groups were 81.9% and 49.0% (χ 2 =36.45, P=0.000), 14.3% and 1.9% (χ 2 =10.54, P=0.006), and 24.8% and 2.9% (χ 2 =22.95, P=0.000), respectively. The incidence of nausea, vomiting and constipation for the two groups were 63.8% and 7.7% (χ 2 =71.52, P=0.000), respectively. The incidence of ≥2 grade esophagitis of CC group and R group were 48.57% and 38.46% (χ 2 =2.17, P=0.141), respectively. The incidence of ≥2

Magnetic resonance assessment of prostate localization variability in intensity-modulated radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Villeirs, Geert M.; Meerleer, Gert O. de; Verstraete, Koenraad L.; Neve, Wilfried J. de

2004-01-01

Purpose: To measure prostate motion with magnetic resonance imaging (MRI) during a course of intensity-modulated radiotherapy. Methods and materials: Seven patients with prostate carcinoma were scanned supine on a 1.5-Tesla MRI system with weekly pretreatment and on-treatment HASTE T2-weighted images in 3 orthogonal planes. The bladder and rectal volumes and position of the prostatic midpoint (PMP) and margins relative to the bony pelvis were measured. Results: All pretreatment positions were at the mean position as computed from the on-treatment scans in each patient. The PMP variability (given as 1 SD) in the anterior-posterior (AP), superior-inferior (SI), and right-left (RL) directions was 2.6, 2.4, and 1.0 mm, respectively. The largest variabilities occurred at the posterior (3.2 mm), superior (2.6 mm), and inferior (2.6 mm) margins. A strong correlation was found between large rectal volume (>95th percentile) and anterior PMP displacement. A weak correlation was found between bladder volume and superior PMP displacement. Conclusions: All pretreatment positions were representative of the subsequent on-treatment positions. A clinical target volume (CTV) expansion of 5.3 mm in any direction was sufficient to ascertain a 95% coverage of the CTV within the planning target volume (PTV), provided that a rectal suppository is administered to avoid rectal overdistension and that the patient has a comfortably filled bladder (<300 mL)

Dose-Effect Relationships for the Submandibular Salivary Glands and Implications for Their Sparing by Intensity Modulated Radiotherapy

International Nuclear Information System (INIS)

Murdoch-Kinch, Carol-Anne; Kim, Hyugnjin M.; Vineberg, Karen A.; Ship, Jonathan; Eisbruch, Avraham

2008-01-01

Purpose: Submandibular salivary glands (SMGs) dysfunction contributes to xerostomia after radiotherapy (RT) of head-and-neck (HN) cancer. We assessed SMG dose-response relationships and their implications for sparing these glands by intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 148 HN cancer patients underwent unstimulated and stimulated SMG salivary flow rate measurements selectively from Wharton's duct orifices, before RT and periodically through 24 months after RT. Correlations of flow rates and mean SMG doses were modeled throughout all time points. IMRT replanning in 8 patients whose contralateral level I was not a target incorporated the results in a new cost function aiming to spare contralateral SMGs. Results: Stimulated SMG flow rates decreased exponentially by (1.2%) Gy as mean doses increased up to 39 Gy threshold, and then plateaued near zero. At mean doses ≤39 Gy, but not higher, flow rates recovered over time at 2.2%/month. Similarly, the unstimulated salivary flow rates decreased exponentially by (3%) Gy as mean dose increased and recovered over time if mean dose was <39 Gy. IMRT replanning reduced mean contralateral SMG dose by average 12 Gy, achieving ≤39 Gy in 5 of 8 patients, without target underdosing, increasing the mean doses to the parotid glands and swallowing structures by average 2-3 Gy. Conclusions: SMG salivary flow rates depended on mean dose with recovery over time up to a threshold of 39 Gy. Substantial SMG dose reduction to below this threshold and without target underdosing is feasible in some patients, at the expense of modestly higher doses to some other organs

Definitive Upfront Stereotactic Ablative Radiotherapy Combined with Image-Guided, Intensity Modulated Radiotherapy (IG-IMRT or IG-IMRT Alone for Locally Advanced Non-Small Cell Lung Cancer.

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Alexander Chi

Full Text Available Image-guided (IG intensity-modulated radiotherapy (IMRT enables maximal tumor margin reduction for the sparing of organs at risk (OARs when used to treat locally advanced non-small cell lung cancer (NSCLC with definitive chemo-radiation. It also allows for the incorporation of stereotactic ablative radiotherapy (SABR into the treatment regimen. Here, we describe our initial experience in combining definitive upfront SABR to the primary lesion with chemo-radiation delivered with conventionally fractionated IG-IMRT to the remaining regional disease; along with clinical outcome following chemo-radiation with conventionally fractionated IG-IMRT alone in the treatment of locally advanced NSCLC.The clinical outcome of 29 patients with locally advanced NSCLC who underwent conventionally fractionated IG-IMRT, or definitive upfront SABR followed by IG-IMRT combined with chemotherapy (induction, concurrent, or both was retrospectively reviewed.After a median follow up of 23.7 months, the median overall survival (OS and progression-free survival (PFS were 19.8 and 11.3 months, respectively. The 2 year local, regional, and distant control was 60%, 62%, and 38%, respectively. No local failure was observed in 3 patients following SABR + IG-IMRT while 6/26 patients failed locally following IG-IMRT alone. SABR + IG-IMRT was well tolerated. No ≥ grade 3 radiation-related toxicity was observed.Definitive upfront SABR followed by IG-IMRT in selected patients with locally advanced NSCLC warrants further investigation in future clinical trials, while chemo-radiation with IG-IMRT alone was well tolerated.

Postoperative radiotherapy of uterine sarcoma: A multicentric retrospective study; Radiotherapie postoperatoire dans les sarcomes uterins: etude retrospective multicentrique

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Champetier, C.; Cowen, D. [Service de radiotherapie, hopital de la Timone, 264, rue Saint-Pierre, 13385 Marseille cedex 05 (France); Hannoun-Levi, J.M. [Centre Antoine-Lacassagne, 33, avenue Valombrose, 06100 Nice (France); Resbeut, M. [Centre de radiotherapie Saint-Louis, rue Andre-Blondel, 83100 Toulon (France); Azria, D. [Centre Val-d' Aurelle-Paul-Lamarque, 208, rue des Apothicaires, 34298 Montpellier cedex 5 (France); Salem, N. [Institut Paoli-Calmettes, 232, boulevard Sainte-Marguerite, 13009 Marseille (France); Tessier, E. [Centre azureen de radiotherapie, 1, place du Docteur-Jean-Luc-Broquerie, 06250 Mougins (France); Ellis, S. [Centre catalan de radiotherapie, 80, rue Pascal-Marie-Agasse, 66000 Perpignan (France)

2011-04-15

Purpose. - Surgery is the treatment of choice for localized uterine sarcomas. We conducted a retrospective study to define prognostic factors. Patients and methods. - We studied 111 cases of patients treated by adjuvant radiotherapy for uterine sarcoma in seven French centers. The median decline was 31 months. We conducted a univariate analysis to identify factors correlated with local recurrence. The statistically significant factors were studied in multivariate analysis by Cox model. Results. - The median dose of external beam radiotherapy was 45 Gy. Forty-three percent of patients had vaginal vault brachytherapy and 21 % chemotherapy. Only 6.3 % of patients had complications of acute grade III and 8.1 % of long-term sequelae of radiotherapy. The survival rate at 5 years was 74.6 %. They noted 12.6 % of isolated locoregional recurrences, against 29.7 % for distant recurrences, 80 % were pulmonary. Factors correlated with the risk of locoregional relapse were menopausal status (P = 0.045) and surgical margins suspicious or not healthy (P = 0.0095). The chemotherapy did not improve overall survival or disease free survival but the numbers were low. Conclusion. - The postoperative radiotherapy provides good local control in this disease. Brachytherapy is sometimes done, but it does not improve local control. Chemotherapy is not a standard localized stage but the rate of metastatic recurrence calls for the development of strategies involving systemic treatment with radiotherapy. (authors)

Influence of the timing of surgery and postoperative radiotherapy on treatment results

International Nuclear Information System (INIS)

Fietkau, R.

2000-01-01

Background: The timing of surgery and postoperative radiotherapy - especially if combined with chemotherapy - has been a subject of interest over the past years. Methods: This analysis was based on a literature review of mostly retrospective publications. Data concerning the interval between surgery and radiotherapy were correlated with the locoregional control, incidence of distant metastases and prognosis of breast cancer, lung carcinoma, and head and neck carcinomas. Results and Conclusions: The reviewed data did not show a clear relationship of the time interval between surgery and start of radiotherapy and locoregional control. However, evaluation of the data was difficult, because in most publications, retrospective analyses were performed and other prognostically more relevant parameters may influence locoregional control stronger than the time interval. In patients with head and neck carcinomas, there is a negative effect of time interval between surgery and radiotherapy on local control if unfavorable factors exist, i.e., close surgical margins, unfavorable pathohistological parameters and low radiation dose. In patients with breast cancer who do not receive chemotherapy, there are inconsistent reports in the literature. If additional chemotherapy is necessary, the sequence surgery, chemotherapy and radiotherapy seems adequate. Although some data suggest that delaying the initiation of radiotherapy due to chemotherapy may increase the risk of local recurrences, there may, on the other hand, be an increased likelihood of systemic metastases, if radiotherapy is applied before chemotherapy. Concerning lung cancer, only one retrospective analysis exists suggesting a better survival of patients with an interval of more than 36 days between surgery and radiotherapy as compared to patients with a shorter interval. (orig.) [de

Improved Dosimetric and Clinical Outcomes With Intensity-Modulated Radiotherapy for Head-and-Neck Cancer of Unknown Primary Origin

International Nuclear Information System (INIS)

Chen, Allen M.; Li Baoqing; Farwell, D. Gregory; Marsano, Joseph; Vijayakumar, Srinivasan; Purdy, James A.

2011-01-01

Purpose: To compare differences in dosimetric, clinical, and quality-of-life endpoints among a cohort of patients treated by intensity-modulated radiotherapy (IMRT) and conventional radiotherapy (CRT) for head-and-neck cancer of unknown primary origin. Methods and Materials: The medical records of 51 patients treated by radiation therapy for squamous cell carcinoma of the head and neck presenting as cervical lymph node metastasis of occult primary origin were reviewed. Twenty-four patients (47%) were treated using CRT, and 27 (53%) were treated using IMRT. The proportions of patients receiving concurrent chemotherapy were 54% and 63%, respectively. Results: The 2-year estimates of overall survival, local-regional control, and disease-specific survival for the entire patient population were 86%, 89%, and84%, respectively. There were no significant differences in any of these endpoints with respect to radiation therapy technique (p > 0.05 for all). Dosimetric analysis revealed that the use of IMRT resulted in significant improvements with respect to mean dose and V30 to the contralateral (spared) parotid gland. In addition, mean doses to the ipsilateral inner and middle ear structures were significantly reduced with IMRT (p < 0.05 for all). The incidence of severe xerostomia in the late setting was 58% and 11% among patients treated by CRT and IMRT, respectively (p < 0.001). The percentages of patients who were G-tube dependent at 6 months after treatment were 42% and 11%, respectively (p < 0.001). Conclusions: IMRT results in significant improvements in the therapeutic ratio among patients treated by radiation therapy for head-and-neck cancer of unknown primary origin.

Treatment planning comparison of electron arc therapy and photon intensity modulated radiotherapy for Askin's tumor of chest wall

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Jamema, Swamidas V.; Sharma, Pramod K.; Laskar, Siddhartha; Deshpande, Deepak D.; Shrivastava, Shyam K.

2007-01-01

Background and Purpose: A dosimetric study to quantitatively compare radiotherapy treatment plans for Askin's tumor using Electron Arc (EA) vs. photon Intensity Modulated Radiotherapy (IMRT). Materials and methods: Five patients treated with EA were included in this study. Treatment plans were generated for each patient using EA and IMRT. Plans were compared using dose volume histograms (DVH) of the Planning Target Volume (PTV) and Organs at Risk (OAR). Results: IMRT resulted in superior PTV coverage, and homogeneous dose distribution compared to EA. For EA, 92% of the PTV was covered to 85% of the dose compared to IMRT in which 96% was covered to 95% of the dose. V 107 that represents the hot spot within the PTV was more in IMRT compared to EA: 7.4(±2)% vs. 3(±0.5)%, respectively. With PTVs located close to the spinal cord (SC), the dose to SC was more with EA, whereas for PTVs located away from the SC, the dose to SC was more with IMRT. The cardiac dose profile was similar to that of SC. Ipsilateral lung received lower doses with IMRT while contralateral lung received higher dose with IMRT compared to EA. For non-OAR normal tissues, IMRT resulted in large volumes of low dose regions. Conclusions: IMRT resulted in superior PTV coverage and sparing of OAR compared to EA plans. Although IMRT seems to be superior to EA, one needs to keep in mind the volume of low dose regions associated with IMRT, especially while treating young children

Dosimetric comparison of intensity-modulated, conformal, and four-field pelvic radiotherapy boost plans for gynecologic cancer: a retrospective planning study

International Nuclear Information System (INIS)

Chan, Philip; Yeo, Inhwan; Perkins, Gregory; Fyles, Anthony; Milosevic, Michael

2006-01-01

To evaluate intensity-modulated radiation therapy (IMRT) as an alternative to conformal radiotherapy (CRT) or 4-field box boost (4FB) in women with gynecologic malignancies who are unsuitable for brachytherapy for technical or medical reasons. Dosimetric and toxicity information was analyzed for 12 patients with cervical (8), endometrial (2) or vaginal (2) cancer previously treated with external beam pelvic radiotherapy and a CRT boost. Optimized IMRT boost treatment plans were then developed for each of the 12 patients and compared to CRT and 4FB plans. The plans were compared in terms of dose conformality and critical normal tissue avoidance. The median planning target volume (PTV) was 151 cm 3 (range 58–512 cm 3 ). The median overlap of the contoured rectum with the PTV was 15 (1–56) %, and 11 (4–35) % for the bladder. Two of the 12 patients, both with large PTVs and large overlap of the contoured rectum and PTV, developed grade 3 rectal bleeding. The dose conformity was significantly improved with IMRT over CRT and 4FB (p ≤ 0.001 for both). IMRT also yielded an overall improvement in the rectal and bladder dose-volume distributions relative to CRT and 4FB. The volume of rectum that received the highest doses (>66% of the prescription) was reduced by 22% (p < 0.001) with IMRT relative to 4FB, and the bladder volume was reduced by 19% (p < 0.001). This was at the expense of an increase in the volume of these organs receiving doses in the lowest range (<33%). These results indicate that IMRT can improve target coverage and reduce dose to critical structures in gynecologic patients receiving an external beam radiotherapy boost. This dosimetric advantage will be integrated with other patient and treatment-specific factors, particularly internal tumor movement during fractionated radiotherapy, in the context of a future image-guided radiation therapy study

Predicting two-year longitudinal MD Anderson Dysphagia Inventory outcomes after intensity modulated radiotherapy for locoregionally advanced oropharyngeal carcinoma.

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Goepfert, Ryan P; Lewin, Jan S; Barrow, Martha P; Fuller, C David; Lai, Stephen Y; Song, Juhee; Hobbs, Brian P; Gunn, G Brandon; Beadle, Beth M; Rosenthal, David I; Garden, Adam S; Kies, Merrill S; Papadimitrakopoulou, Vali A; Schwartz, David L; Hutcheson, Katherine A

2017-04-01

To determine the factors associated with longitudinal patient-reported dysphagia as measured by the MD Anderson Dysphagia Inventory (MDADI) in locoregionally advanced oropharyngeal carcinoma (OPC) survivors treated with split-field intensity modulated radiotherapy (IMRT). Retrospective patient analysis. A retrospective analysis combined data from three single-institution clinical trials for stage III/IV head and neck carcinoma. According to trial protocols, patients had prospectively collected MDADI at baseline, 6, 12, and 24 months after treatment. OPC patients with baseline and at least one post-treatment MDADI were included. Longitudinal analysis was completed with multivariate linear mixed effects modeling. There were 116 patients who met inclusion criteria. Mean baseline MDADI composite was 88.3, dropping to 73.8 at 6 months, and rising to 78.6 and 83.3 by 12 and 24 months, respectively (compared to baseline, all P dysphagia early after split-field IMRT for locoregionally advanced OPC that remains apparent 6 months after treatment. MDADI scores recover slowly thereafter, but remain depressed at 24 months compared to baseline. Higher tumor stage and smoking status are important markers of patient-reported function through the course of treatment, suggesting these are important groups for heightened surveillance and more intensive interventions to optimize swallowing outcomes. 4 Laryngoscope, 127:842-848, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

A retrospective comparison of outcome and toxicity of preoperative image-guided intensity-modulated radiotherapy versus conventional pelvic radiotherapy for locally advanced rectal carcinoma

International Nuclear Information System (INIS)

Huang, Chun-Ming; Huang, Ming-Yii; Tsai, Hsiang-Lin; Huang, Ching-Wen; Ma, Cheng-Jen; Lin, Chih-Hung; Huang, Chih-Jen; Wang, Jaw-Yuan

2017-01-01

The aim of the study was to compare clinical outcomes and toxicity between 3D conformal radiotherapy (3DCRT) and image-guided intensity-modulated radiotherapy (IG-IMRT) administered through helical tomotherapy in locally advanced rectal cancer (LARC) patients receiving preoperative chemoradiotherapy. We reviewed 144 patients with Stage II–III rectal cancer receiving preoperative fluoropyrimidine-based chemoradiotherapy followed by radical resection. Tumor responses following chemoradiotherapy were evaluated using the Dworak tumor regression grade (TRG). Of the 144 patients, 45 received IG-IMRT and 99 received 3DCRT. A significant reduction in Grade 3 or 4 acute gastrointestinal toxicity (IG-IMRT, 6.7%; 3DCRT, 15.1%; P = 0.039) was observed by IG-IMRT. The pathologic complete response (pCR) rate did not differ between the IG-IMRT and the 3DCRT group (17.8% vs 15.1%, P = 0.52). Patients in the IG-IMRT group had the trend of favorable tumor regressions (TRG 3 or 4) compared with those in the 3DCRT group (66.7% vs 43.5%, P = 0.071). The median follow-up was 53 months (range, 18–95 months) in the 3DCRT group and 43 months (range, 17–69 months) in the IG-IMRT group. Four-year overall, disease-free, and local failure–free survival rates of the IG-IMRT and 3DCRT groups were 81.6% and 67.9% (P = 0.12), 53.8% and 51.8% (P = 0.51), and 88% and 75.1% (P = 0.031), respectively. LARC patients treated with preoperative IG-IMRT achieved lower acute gastrointestinal adverse effects and a higher local control rate than those treated with 3DCRT, but there was no prominent difference in distant metastasis rate and overall survival between two treatment modalities.

Quality of Life and Survival Outcome for Patients With Nasopharyngeal Carcinoma Receiving Three-Dimensional Conformal Radiotherapy vs. Intensity-Modulated Radiotherapy-A Longitudinal Study

International Nuclear Information System (INIS)

Fang, F.-M.; Chien, C.-Y.; Tsai, W.-L.; Chen, H.-C.; Hsu, H.-C.; Lui, C.-C.; Huang, T.-L.

2008-01-01

Purpose: To investigate the changes of quality of life (QoL) and survival outcomes for patients with nasopharyngeal carcinoma (NPC) treated by three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT). Methods and Materials: Two hundred and three newly diagnosed NPC patients, who were curatively treated by 3D-CRT (n = 93) or IMRT (n = 110) between March 2002 and July 2004, were analyzed. The distributions of clinical stage according to American Joint Committee on Cancer 1997 were I: 15 (7.4%), II: 78 (38.4%), III: 74 (36.5%), and IV: 36 (17.7%). QoL was longitudinally assessed by the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and the EORTC QLQ-H and N35 questionnaires at the five time points: before RT, during RT (36 Gy), and 3 months, 12 months, and 24 months after RT. Results: The 3-year locoregional control, metastasis-free survival, and overall survival rates were 84.8%, 76.7%, and 81.7% for the 3D-CRT group, respectively, compared with 84.2%, 82.6%, and 85.4% for the IMRT group (p value > 0.05). A general trend of maximal deterioration in most QoL scales was observed during RT, followed by a gradual recovery thereafter. There was no significant difference in most scales between the two groups at each time point. The exception was that patients treated by IMRT had a both statistically and clinically significant improvement in global QoL, fatigue, taste/smell, dry mouth, and feeling ill at the time point of 3 months after RT. Conclusions: The potential advantage of IMRT over 3D-CRT in treating NPC patients might occur in QoL outcome during the recovery phase of acute toxicity

The efficacy of postoperative radiotherapy in localized primary soft tissue sarcoma treated with conservative surgery

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Zhao, Ru-Ping; Yu, Xiao-Li; Zhang, Zhen; Jia, Li-Juan; Feng, Yan; Yang, Zhao-Zhi; Chen, Xing-Xing; Wang, Jian; Ma, Sheng-Lin; Guo, Xiao-Mao

2016-01-01

To evaluate the efficacy of postoperative radiotherapy (RT) on local failure-free survival (LFFS), distant metastasis-free survival (DMFS) and overall survival (OS) in patients with localized primary soft tissue sarcoma (STS) and to identify prognostic factors. Between January 2000 and July 2010, 220 consecutive patients with localized primary STS, who received conservative surgery with or without postoperative RT, were enrolled in the study. Survival curves were constructed by the Kaplan-Meier method and log-rank test was used to assess statistical significance. Multivariate analysis was applied to identify the prognostic factors. After a median follow-up of 68 months (range, 5–127 months), the 5-year LFFS, DMFS and OS were 70.0, 78.2 and 71.2 %, respectively. Tumor size, histological subtypes, margin status and postoperative RT were independent predictors for OS. Postoperative RT was associated with a significant reduced local recurrence risk versus surgery alone (hazard ratio [HR] = 0.408, 95 % confidence interval [CI] 0.235–0.707, P = 0.001), with 5-year LFFS of 81.1 and 63.6 %, respectively (log-rank, P = 0.004). The log-rank test showed that postoperative RT had a tendency of improving OS compared with surgery alone, with 5-year OS of 74.8 and 65.0 %, respectively (P = 0.089). Multivariate analysis demonstrated that postoperative RT significantly reduced mortality rate compared with surgery alone (HR = 0.512, 95 % CI 0.296–0.886, p = 0.017), especially in patients with liposarcoma (p = 0.034). Postoperative radiotherapy reduce both local recurrence and STS mortality in patients with localized primary STS. The efficacy of RT on survival warrants further prospective study. The online version of this article (doi:10.1186/s13014-016-0605-y) contains supplementary material, which is available to authorized users

Candidate Dosimetric Predictors of Long-Term Swallowing Dysfunction After Oropharyngeal Intensity-Modulated Radiotherapy

International Nuclear Information System (INIS)

Schwartz, David L.; Hutcheson, Katherine; Barringer, Denise; Tucker, Susan L.; Kies, Merrill; Holsinger, F. Christopher; Ang, K. Kian; Morrison, William H.; Rosenthal, David I.; Garden, Adam S.; Dong Lei; Lewin, Jan S.

2010-01-01

Purpose: To investigate long-term swallowing function in oropharyngeal cancer patients treated with intensity-modulated radiotherapy (IMRT), and to identify novel dose-limiting criteria predictive for dysphagia. Methods and Materials: Thirty-one patients with Stage IV oropharyngeal squamous carcinoma enrolled on a Phase II trial were prospectively evaluated by modified barium swallow studies at baseline, and 6, 12, and 24 months post-IMRT treatment. Candidate dysphagia-associated organs at risk were retrospectively contoured into original treatment plans. Twenty-one (68%) cases were base of tongue and 10 (32%) were tonsil. Stage distribution was T1 (12 patients), T2 (10), T3 (4), T4 (2), and TX (3), and N2 (24), N3 (5), and NX (2). Median age was 52.8 years (range, 42-78 years). Thirteen patients (42%) received concurrent chemotherapy during IMRT. Thirteen (42%) were former smokers. Mean dose to glottic larynx for the cohort was limited to 18 Gy (range, 6-39 Gy) by matching IMRT to conventional low-neck fields. Results: Dose-volume constraints (V30 < 65% and V35 < 35% for anterior oral cavity and V55 < 80% and V65 < 30% for high superior pharyngeal constrictors) predictive for objective swallowing dysfunction were identified by univariate and multivariate analyses. Aspiration and feeding tube dependence were observed in only 1 patient at 24 months. Conclusions: In the context of glottic laryngeal shielding, we describe candidate oral cavity and superior pharyngeal constrictor organs at risk and dose-volume constraints associated with preserved long-term swallowing function; these constraints are currently undergoing prospective validation. Strict protection of the glottic larynx via beam-split IMRT techniques promises to make chronic aspiration an uncommon outcome.

Intra-fractional uncertainties in image-guided intensity-modulated radiotherapy (IMRT) of prostate cancer

International Nuclear Information System (INIS)

Polat, Buelent; Guenther, Iris; Wilbert, Juergen; Goebel, Joachim; Sweeney, Reinhart A.; Flentje, Michael; Guckenberger, Matthias

2008-01-01

To evaluate intra-fractional uncertainties during intensity-modulated radiotherapy (IMRT) of prostate cancer. During IMRT of 21 consecutive patients, kilovolt (kV) cone-beam computed tomography (CBCT) images were acquired prior to and immediately after treatment: a total of 252 treatment fractions with 504 CBCT studies were basis of this analysis. The prostate position in anterior-posterior (AP) direction was determined using contour matching; patient set-up based on the pelvic bony anatomy was evaluated using automatic image registration. Internal variability of the prostate position was the difference between absolute prostate and patient position errors. Intra-fractional changes of prostate position, patient position, rectal distension in AP direction and bladder volume were analyzed. With a median treatment time of 16 min, intra-fractional drifts of the prostate were > 5 mm in 12% of all fractions and a margin of 6 mm was calculated for compensation of this uncertainty. Mobility of the prostate was independent from the bony anatomy with poor correlation between absolute prostate motion and motion of the bony anatomy (R 2 = 0.24). A systematic increase of bladder filling by 41 ccm on average was observed; however, these changes did not influence the prostate position. Small variations of the prostate position occurred independently from intra-fractional changes of the rectal distension; a weak correlation between large internal prostate motion and changes of the rectal volume was observed (R 2 = 0.55). Clinically significant intra-fractional changes of the prostate position were observed and margins of 6 mm were calculated for this intra-fractional uncertainty. Repeated or continuous verification of the prostate position may allow further margin reduction. (orig.)

Intra-fractional uncertainties in image-guided intensity-modulated radiotherapy (IMRT) of prostate cancer

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Polat, Buelent; Guenther, Iris; Wilbert, Juergen; Goebel, Joachim; Sweeney, Reinhart A.; Flentje, Michael; Guckenberger, Matthias [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology

2008-12-15

To evaluate intra-fractional uncertainties during intensity-modulated radiotherapy (IMRT) of prostate cancer. During IMRT of 21 consecutive patients, kilovolt (kV) cone-beam computed tomography (CBCT) images were acquired prior to and immediately after treatment: a total of 252 treatment fractions with 504 CBCT studies were basis of this analysis. The prostate position in anterior-posterior (AP) direction was determined using contour matching; patient set-up based on the pelvic bony anatomy was evaluated using automatic image registration. Internal variability of the prostate position was the difference between absolute prostate and patient position errors. Intra-fractional changes of prostate position, patient position, rectal distension in AP direction and bladder volume were analyzed. With a median treatment time of 16 min, intra-fractional drifts of the prostate were > 5 mm in 12% of all fractions and a margin of 6 mm was calculated for compensation of this uncertainty. Mobility of the prostate was independent from the bony anatomy with poor correlation between absolute prostate motion and motion of the bony anatomy (R{sup 2} = 0.24). A systematic increase of bladder filling by 41 ccm on average was observed; however, these changes did not influence the prostate position. Small variations of the prostate position occurred independently from intra-fractional changes of the rectal distension; a weak correlation between large internal prostate motion and changes of the rectal volume was observed (R{sup 2} = 0.55). Clinically significant intra-fractional changes of the prostate position were observed and margins of 6 mm were calculated for this intra-fractional uncertainty. Repeated or continuous verification of the prostate position may allow further margin reduction. (orig.)

Pretreatment combination of platelet counts and neutrophil–lymphocyte ratio predicts survival of nasopharyngeal cancer patients receiving intensity-modulated radiotherapy

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Lin YH

2017-05-01

Full Text Available Yu-Hsuan Lin,1 Kuo-Ping Chang,2 Yaoh-Shiang Lin,2,3 Ting-Shou Chang2–4 1Department of Otolaryngology, Head and Neck Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 2Department of Otolaryngology, Head and Neck Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, 3Department of Otolaryngology, Head and Neck Surgery, National Defense Medical Center, Taipei, 4Institute of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China Background: Increased cancer-related inflammation has been associated with unfavorable clinical outcomes. The combination of platelet count and neutrophil–lymphocyte ratio (COP-NLR has related outcomes in several cancers, except for nasopharyngeal carcinoma (NPC. This study evaluated the prognostic value of COP-NLR in predicting outcome in NPC patients treated with intensity-modulated radiotherapy (IMRT.Materials and methods: We analyzed the data collected from 232 NPC patients. Pretreatment total platelet counts, neutrophil–lymphocyte ratio (NLR, and COP-NLR score were evaluated as potential predictors. Optimal cutoff values for NLR and platelets were determined using receiver operating curve. Patients with both elevated NLR (>3 and platelet counts (>300×109/L were assigned a COP-NLR score of 2; those with one elevated or no elevated value were assigned a COP-NLR a score of 1 or 0. Cox proportional hazards model was used to test the association of these factors and relevant 3-year survivals.Results: Patients (COP-NLR scores 1 and 2=85; score 0=147 were followed up for 55.19 months. Univariate analysis showed no association between pretreatment NLR >2.23 and platelet counts >290.5×109/L and worse outcomes. Multivariate analysis revealed that those with COP-NLR scores of 0 had better 3-year disease-specific survival (P=0.02, overall survival (P=0.024, locoregional relapse-free survival (P=0.004, and distant

Influence of jaw tracking in intensity-modulated and volumetric-modulated arc radiotherapy for head and neck cancers: a dosimetric study

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Mani, Karthick Raj [Research and Development Centre, Bharathiar University, Tamilnadu (India); Upadhayay, Sagar [Radiation Oncology, Kathmandu Cancer Center, Bhaktapur (Nepal); Das, K. J. Maria [Dept. of Radiotherapy, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Uttar Pradesh (India)

2017-03-15

To Study the dosimetric advantage of the Jaw tracking technique in intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) for Head and Neck Cancers. We retrospectively selected 10 previously treated head and neck cancer patients stage (T1/T2, N1, M0) in this study. All the patients were planned for IMRT and VMAT with simultaneous integrated boost technique. IMRT and VMAT plans were performed with jaw tracking (JT) and with static jaw (SJ) technique by keeping the same constraints and priorities for a particular patient. Target conformity, dose to the critical structures and low dose volumes were recorded and analyzed for IMRT and VMAT plans with and without JT for all the patients. The conformity index average of all patients followed by standard deviation (x¯x¯ ± σx¯σx¯) of the JT-IMRT, SJ-IMRT, JT-VMAT, and SJ-VMAT were 1.72 ± 0.56, 1.67 ± 0.57, 1.83 ± 0.65, and 1.85 ± 0.64, and homogeneity index were 0.059 ± 0.05, 0.064 ± 0.05, 0.064 ± 0.04, and 0.064 ± 0.05. JT-IMRT shows significant mean reduction in right parotid and left parotid shows of 7.64% (p < 0.001) and 7.45% (p < 0.001) compare to SJ-IMRT. JT-IMRT plans also shows considerable dose reduction to thyroid, inferior constrictors, spinal cord and brainstem compared to the SJ-IMRT plans. Significant dose reductions were observed for critical structure in the JT-IMRT compared to SJ-IMRT technique. In JT-VMAT plans dose reduction to the critical structure were not significant compared to the SJ-IMRT due to relatively lesser monitor units.

Cardiac Side-effects From Breast Cancer Radiotherapy.

Science.gov (United States)

Taylor, C W; Kirby, A M

2015-11-01

Breast cancer radiotherapy reduces the risk of cancer recurrence and death. However, it usually involves some radiation exposure of the heart and analyses of randomised trials have shown that it can increase the risk of heart disease. Estimates of the absolute risks of radiation-related heart disease are needed to help oncologists plan each individual woman's treatment. The risk for an individual woman varies according to her estimated cardiac radiation dose and her background risk of ischaemic heart disease in the absence of radiotherapy. When it is known, this risk can then be compared with the absolute benefit of the radiotherapy. At present, many UK cancer centres are already giving radiotherapy with mean heart doses of less than 3 Gy and for most women the benefits of the radiotherapy will probably far outweigh the risks. Technical approaches to minimising heart dose in breast cancer radiotherapy include optimisation of beam angles, use of multileaf collimator shielding, intensity-modulated radiotherapy, treatment in a prone position, treatment in deep inspiration (including the use of breath-hold and gating techniques), proton therapy and partial breast irradiation. The multileaf collimator is suitable for many women with upper pole left breast cancers, but for women with central or lower pole cancers, breath-holding techniques are now recommended in national UK guidelines. Ongoing work aims to identify ways of irradiating pan-regional lymph nodes that are effective, involve minimal exposure of organs at risk and are feasible to plan, deliver and verify. These will probably include wide tangent-based field-in-field intensity-modulated radiotherapy or arc radiotherapy techniques in combination with deep inspiratory breath-hold, and proton beam irradiation for women who have a high predicted heart dose from intensity-modulated radiotherapy. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Assessment of renal function after conformal radiotherapy and intensity-modulated radiotherapy by functional {sup 1}H-MRI and {sup 23}Na-MRI

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Haneder, S.; Michaely, H.J.; Schoenberg, S.O. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Konstandin, S.; Schad, L.R. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Computer-Assisted Clinical Medicine; Siebenlist, K.; Wertz, H.; Wenz, F.; Lohr, F.; Boda-Heggemann, J. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Dept. of Radiation Oncology

2012-12-15

Purpose: Adjuvant radiochemotherapy (RCHT) improves survival of patients with locally advanced gastric cancer. Conventional three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to a significant amount of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides excellent target coverage with improved kidney sparing. Few long-term results on IMRT for gastric cancer, however, have been published. Functional magnetic resonance imaging (fMRI) at 3.0 T including blood oxygenation-level dependent (BOLD) imaging, diffusion-weighted imaging (DWI) and, for the first time, {sup 23}Na imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT. Patients and methods Four disease-free patients (2 after 3D-CRT and 2 after IMRT; FU for all patients > 5 years) were included in this feasibility study. Morphological sequences, axial DWI images, 2D-gradient echo (GRE)-BOLD images, and {sup 23}Na images were acquired. Mean values/standard deviations for ({sup 23}Na), the apparent diffusion coefficient (ADC), and R2{sup *} values were calculated for the upper/middle/lower parts of both kidneys. Corticomedullary {sup 23}Na-concentration gradients were determined. Results: Surprisingly, IG-IMRT patients showed no morphological alterations and no statistically significant differences of ADC and R2{sup *} values in all renal parts. Values for mean corticomedullary {sup 23}Na-concentration matched those for healthy volunteers. Results were similar in 3D-CRT patients, except for the cranial part of the left kidney. This was atrophic and presented significantly reduced functional parameters (p = 0.001 - p = 0.033). Reduced ADC values indicated reduced cell density and reduced extracellular space. Cortical and medullary R2{sup *} values of the left cranial kidney in the 3D-CRT group were higher, indicating more deoxygenated hemoglobin due to reduced blood flow/oxygenation. ({sup 23}Na) of the renal cranial parts in

Comparison of intensity-modulated radiotherapy and volumetric-modulated arc therapy dose measurement for head and neck cancer using optical stimulated luminescence dosimeter

International Nuclear Information System (INIS)

Lai, Lu-Han; Chuang, Keh-Shih; Lin, Hsin-Hon; Liu, Yi-Chi; Kuo, Chiung-Wen; Lin, Jao-Perng

2017-01-01

The in-vivo dose distributions of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT), a newly developed technique, for head and neck cancer have been investigated for several years. The present study used a head-and-neck RANDO phantom to simulate the clinical conditions of nasopharyngeal carcinoma and compare the radiation doses between VMAT and IMRT. Three types of planning target volume (PTV) profiles were targeted by reducing the PTV surface margin by 0, 3, and 5 mm. An optically stimulated luminescence dosimeter was used to measure the surface doses. The results revealed that VMAT provided on average 16.8–13.8% lower surface doses within the PTV target areas than IMRT. When the PTV margin was reduced by 0 mm, the surface doses for IMRT reached their maximum value, accounting for 75.1% of its prescribed dose (Dp); however, the Dp value of VMAT was only 61.1%. When the PTV margin was reduced by 3 or 5 mm, the surface doses decreased considerably. The observed surface doses were insufficient when the tumours invaded the body surface; however, VMAT exerted larger skin-sparing effects than IMRT when the tumours away from the skin. These results suggest that the skin doses for these two techniques are insufficient for surface tumours. Notably, VMAT can provide lower skin doses for deep tumours. - Highlights: • The surface doses of NPC patients are compared between VMAT and IMRT. • VMAT exerts lower skin dose than IMRT for deep tumours. • The surface tumour coverage is insufficient for VMAT and IMRT.

Postoperative radiotherapy for stage I/II seminoma: results for 212 patients

International Nuclear Information System (INIS)

Bauman, Glenn S.; Venkatesan, Varagur M.; Ago, C. Tetteh; Radwan, John S.; Dar, A. Rashid; Winquist, Eric W.

1998-01-01

Purpose: A retrospective review of patients with Stage I and II seminoma treated at a regional cancer center was performed to assess the long term efficacy and toxicity associated with post operative radiotherapy. Methods and Materials: Between 1950 and 1995, 212 patients seen at the London Regional Cancer Centre received adjuvant radiotherapy following orchiectomy for Stage I (169) and II (43) seminoma. Median follow-up for the group was 7.5 years. Results: Progression free, cause specific, and overall survival were 95%, 98%, and 95% at 5 years, and 94%, 98%, and 94% at 10 years respectively. An increased risk of failure was noted among patients with bulky Stage II disease. No other prognostic factors for relapse were identified. Late toxicity was uncommon with only 12/212 (6%) developing any late GI toxicity potentially attributable to radiotherapy. The incidence of second malignancies (excluding second testicular tumors) was 6/212 (actuarial:1%, 1%, 6% at 5,10,15 years respectively). There was a trend toward increased acute complications for patients treated with larger volumes of radiation. No prognostic factors associated with increased risk of late toxicity or second malignancy were identified, likely a consequence of the small number of these events. Conclusion: Survival and toxicity were comparable to that reported in the literature. Post-operative radiotherapy remains a safe and efficacious adjuvant treatment for Stage I and early Stage II seminoma

Intensity-modulated radiation therapy: a review with a physics perspective.

Science.gov (United States)

Cho, Byungchul

2018-03-01

Intensity-modulated radiation therapy (IMRT) has been considered the most successful development in radiation oncology since the introduction of computed tomography into treatment planning that enabled three-dimensional conformal radiotherapy in 1980s. More than three decades have passed since the concept of inverse planning was first introduced in 1982, and IMRT has become the most important and common modality in radiation therapy. This review will present developments in inverse IMRT treatment planning and IMRT delivery using multileaf collimators, along with the associated key concepts. Other relevant issues and future perspectives are also presented.

Qualitative risk analysis in the process of treatment in radiation oncology for the steps performed by the technician/technologist in intensity modulated radiotherapy (lMRT)

International Nuclear Information System (INIS)

Teixeira, Flavia C.S.; Faria, Alessandra L.; Pereira, Danielle P.S.; Silva, Fabiana M.I.

2013-01-01

The efficacy of radiation therapy is to eradicate the tumor while preserving the integrity of normal tissues. Technological advances have allowed to develop techniques capable of modulating doses delivered to the target volume, providing more effective treatments. However, the operational complexity of these techniques makes the benefits offered are directly proportional to the chances of occurrences of serious errors. The objective of this work is to analyze the steps performed by the technician/technologist in Intensity Modulated Radiotherapy (IMRT), to detect possible errors in order to determine ways to mitigate them. After literature regarding errors in the radiation therapy, a prospective analysis was performed in the first half of 2012 in a radiation clinic located in the city of Rio de Janeiro, in which 11 technicians/technologists contributed to the survey data analysis. The method of risk analysis Failure Mode and Effects Analysis was used for prospective analysis of accidents/incidents, with respect to a qualitative assessment . The method allowed mapping 16 steps performed by technicians/technologists in the treatments with IMRT, identifying possible failures and their causes allowing to find ways to avoid possible errors. This analysis helped to confirm that the qualification and continuing education of technicians/technologists, allied to implement quality assurance programs and a computerized management can make a tool capable of IMRT to achieve the greatest challenge of radiotherapy. (author)

The use of hypofractionated intensity-modulated irradiation in the treatment of glioblastoma multiforme: preliminary results of a prospective trial.

Science.gov (United States)

Sultanem, Khalil; Patrocinio, Horacio; Lambert, Christine; Corns, Robert; Leblanc, Richard; Parker, William; Shenouda, George; Souhami, Luis

2004-01-01

Despite major advances in treatment modalities, the prognosis of patients with glioblastoma multiforme (GBM) remains poor. Exploring hypofractionated regimens to replace the standard 6-week radiotherapy schedule is an attractive strategy as an attempt to prevent accelerated tumor cell repopulation. There is equally interest in dose escalation to the gross tumor volume where the majority of failures occur. We report our preliminary results using hypofractionated intensity-modulated accelerated radiotherapy regimen in the treatment of patients with GBM. Between July 1998 and December 2001, 25 patients with histologically proven diagnosis of GBM, Karnofsky performance status > or =60, and a postoperative tumor volume step-and-shoot technique), 60 Gy in 20 daily fractions of 3 Gy each were given to the GTV, whereas the planning target volume received a minimum of 40 Gy in 20 fractions of 2 Gy each at its periphery. Treatments were delivered over a 4-week period using 5 daily fractions per week. Dose was prescribed at the isocenter (ICRU point). Three beam angles were used in all of the cases. Treatments were well tolerated. Acute toxicity was limited to increased brain edema during radiotherapy in 2 patients who were on tapering doses of corticosteroids. This was corrected by increasing the steroid dose. At a median follow-up of 8.8 months, no late toxicity was observed. One patient experienced visual loss at 9 months after completion of treatment. MRI suggested nonspecific changes to the optic chiasm. On review of the treatment plan, the total dose to the optic chiasm was confirmed to be equal to or less than 40 Gy in 20 fractions. When Radiation Therapy Oncology Group recursive partitioning analysis was used, 10 patients were class III-IV, and 15 patients were class V-VI. To date, 21 patients have had clinical and/or radiologic evidence of disease progression, and 16 patients have died. The median survival was 9.5 months (range: 2.8-22.9 months), the 1-year survival

Dysphagia in head and neck cancer patients following intensity modulated radiotherapy (IMRT)

International Nuclear Information System (INIS)

Peponi, Evangelia; Glanzmann, Christoph; Willi, Bettina; Huber, Gerhard; Studer, Gabriela

2011-01-01

To evaluate the objective and subjective long term swallowing function, and to relate dysphagia to the radiation dose delivered to the critical anatomical structures in head and neck cancer patients treated with intensity modulated radiation therapy (IMRT, +/- chemotherapy), using a midline protection contour (below hyoid, ~level of vertebra 2/3). 82 patients with stage III/IV squamous cell carcinoma of the larynx, oropharynx, or hypopharynx, who underwent successful definitive (n = 63, mean dose 68.9Gy) or postoperative (n = 19, mean dose 64.2Gy) simultaneous integrated boost (SIB) -IMRT either alone or in combination with chemotherapy (85%) with curative intent between January 2002 and November 2005, were evaluated retrospectively. 13/63 definitively irradiated patients (21%) presented with a total gross tumor volume (tGTV) >70cc (82-173cc; mean 106cc). In all patients, a laryngo-pharyngeal midline sparing contour outside of the PTV was drawn. Dysphagia was graded according subjective patient-reported and objective observer-assessed instruments. All patients were re-assessed 12 months later. Dose distribution to the swallowing structures was calculated. At the re-assessment, 32-month mean post treatment follow-up (range 16-60), grade 3/4 objective toxicity was assessed in 10%. At the 32-month evaluation as well as at the last follow up assessment mean 50 months (16-85) post-treatment, persisting swallowing dysfunction grade 3 was subjectively and objectively observed in 1 patient (1%). The 5-year local control rate of the cohort was 75%; no medial marginal failures were observed. Our results show that sparing the swallowing structures by IMRT seems effective and relatively safe in terms of avoidance of persistent grade 3/4 late dysphagia and local disease control

Breath-hold technique in conventional APPA or intensity-modulated radiotherapy for Hodgkin's lymphoma. Comparison of ILROG IS-RT and the GHSG IF-RT

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Kriz, Jan; Spickermann, Max; Lehrich, Philipp; Reinartz, Gabriele; Eich, Hans; Haverkamp, Uwe [University of Muenster, Department of Radiation Oncology, Muenster (Germany); Schmidberger, Heinz [University Mainz, Department of Radiation Oncology, Mainz (Germany)

2015-09-15

The present study addresses the role of intensity-modulated radiotherapy (IMRT) in contrast to standard RT (APPA) for patients with Hodgkin's lymphoma (HL) with a focus on deep inspiration breath-hold (DIBH) technique and a comparison between the International Lymphoma Radiation Oncology Group (ILROG) Involved Site Radiotherapy (IS-RT) versus the German Hodgkin Study Group (GHSG) Involved Field Radiotherapy (IF-RT). APPA treatment and 2 IMRT plans were compared for 11 patients with HL. Furthermore, treatment with DIBH versus free breathing (FB) and two different treatment volumes, i.e. IF-RT versus IS-RT, were compared. IMRT was planned as a sliding-window technique with 5 and 7 beam angles. For each patient 12 different treatment plans were calculated (132 plans). Following organs at risk (OAR) were analysed: lung, heart, spinal cord, oesophagus, female breast and skin. Comparisons of the different values with regard to dose-volume histograms (DVH), conformity and homogeneity indices were made. IS-RT reduces treatment volumes. With respect to the planning target volume (PTV), IMRT achieves better conformity but the same homogeneity. Regarding the D{sub mean} for the lung, IMRT shows increased doses, while RT in DIBH reduces doses. The IMRT shows improved values for D{sub max} concerning the spinal cord, whereas the APPA shows an improved D{sub mean} of the lung and the female breast. IS-RT reduces treatment volumes. Intensity-modulated radiotherapy shows advantages in the conformity. Treatment in DIBH also reduces the dose applied to the lungs and the heart. (orig.) [German] Ziel dieser Auswertung ist es, die konventionelle APPA-Feldanordnung mit der Intensitaetsmodulierten Radiotherapie (IMRT) bei Patienten mit Hodgkin-Lymphom (HL) zu vergleichen. Ein besonderer Fokus liegt hierbei auf der Bestrahlung in tiefer Inspiration und Atemanhaltetechnik (DIBH). Des Weiteren wurde die ''Involved-site''-Radiotherapie (IS-RT) der International

Technological advances in radiotherapy of rectal cancer

DEFF Research Database (Denmark)

Appelt, Ane L; Sebag-Montefiore, David

2016-01-01

PURPOSE OF REVIEW: This review summarizes the available evidence for the use of modern radiotherapy techniques for chemoradiotherapy for rectal cancer, with specific focus on intensity-modulated radiotherapy (IMRT) and volumetric arc therapy (VMAT) techniques. RECENT FINDINGS: The dosimetric...

Treatment Planning Study to Determine Potential Benefit of Intensity-Modulated Radiotherapy Versus Conformal Radiotherapy for Unresectable Hepatic Malignancies

International Nuclear Information System (INIS)

Eccles, Cynthia L.; Bissonnette, Jean-Pierre; Craig, Tim; Taremi, Mojgan; Wu Xia; Dawson, Laura A.

2008-01-01

Purpose: To compare intensity-modulated radiotherapy (IMRT) with conformal RT (CRT) for hypofractionated isotoxicity liver RT and explore dose escalation using IMRT for the same/improved nominal risk of liver toxicity in a treatment planning study. Methods and Materials: A total of 26 CRT plans were evaluated. Prescription doses (24-54 Gy within six fractions) were individualized on the basis of the effective liver volume irradiated maintaining ≤5% risk of radiation-induced liver disease. The dose constraints included bowel (0.5 cm 3 ) and stomach (0.5 cm 3 ) to ≤30 Gy, spinal cord to ≤25 Gy, and planning target volume (PTV) to ≤140% of the prescribed dose. Two groups were evaluated: (1) PTV overlapping or directly adjacent to serial functioning normal tissues (n = 14), and (2) the liver as the dose-limiting normal tissue (n = 12). IMRT plans using direct machine parameter optimization maintained the CRT plan beam arrangements, an estimated radiation-induced liver disease risk of 5%, and underwent dose escalation, if all normal tissue constraints were maintained. Results: IMRT improved PTV coverage in 19 of 26 plans (73%). Dose escalation was feasible in 9 cases by an average of 3.8 Gy (range, 0.6-13.2) in six fractions. Three of seven plans without improved PTV coverage had small gross tumor volumes (≤105 cm 3 ) already receiving 54 Gy, the maximal prescription dose allowed. In the remaining cases, the PTV range was 9.6-689 cm 3 ; two had overlapped organs at risk; and one had four targets. IMRT did not improve these plans owing to poor target coverage (n = 2) and nonliver (n = 2) dose limits. Conclusion: Direct machine parameter optimization IMRT improved PTV coverage while maintaining normal tissue tolerances in most CRT liver plans. Dose escalation was possible in a minority of patients

Intensity-Modulated Radiotherapy Causes Fewer Side Effects than Three-Dimensional Conformal Radiotherapy When Used in Combination With Brachytherapy for the Treatment of Prostate Cancer

International Nuclear Information System (INIS)

Forsythe, Kevin; Blacksburg, Seth; Stone, Nelson; Stock, Richard G.

2012-01-01

Purpose: To measure the benefits of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3D-CRT) when used in combination with brachytherapy for the treatment of prostate cancer. Methods and Materials: We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of 103 Pd or 125 I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson χ 2 test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors. Results: Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19% mild, 44% moderate, and 37% severe; patients treated with IMRT scored their urinary symptoms as follows: 36% mild, 47% moderate, and 17% severe (p < 0.001). The 3D-CRT patients rated their QOL as follows: 35% positive, 20% neutral, and 45% negative; IMRT patients rated their QOL as follows: 51% positive, 18% neutral, and 31% negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade ≥2 rectal bleeding was reported by 11% of 3D-CRT patients and 7

Postoperative radiotherapy prophylaxis of periarticular ossification after total hip replacement

International Nuclear Information System (INIS)

Sauer, R.; Seegenschmiedt, M.H.; Andreas, P.; Goldmann, A.; Beck, H.

1992-01-01

Since June 1988, we have treated 77 patients or 80 hips respectively with prophylactic irradiation. Individual risk factors included severe coxarthrosis grade IV, ipsi- or contralateral heterotopic ossification and severe hip trauma. As of July 1991 60 patients with a minimum follow-up of six months could be analyzed using clinical and radiological scoring systems. The patients had been prospectively randomized in two different treatment arms: 32 patients were treated with low dose (LD), five times 2 Gy daily fractions to a total dose of 10 Gy, whereas 28 patients were treated with high dose (HD), ten times 2 Gy (eight patients) or five times 3.5 Gy (20 patients). Operative procedures and individual risk factors were equally distributed in both groups. 23 patients (38% received indometacin three times 25 mg for six weeks, 19 patients (32%) diphosphonate EHDP 20 mg/kg body weight and 18 patients (30%) had no additional medication. 56/60 (93%) patients developed no significant heterotopic ossification and/or remained without impairment of their postoperative radiological and clinical hip status according to the applied Brooker and Harris Scores. Only 4/60 (7%) patients demonstrated treatment failures developing postoperative worsening one grade of Brooker score in two patients and two and three grades of Brooker score in the two others. Only 1/49 patients experienced a treatment failure, when radiotherapy had been initiated before and at postoperative day 4 compared to 3/11 patients initiated after postoperative day 4 (p [de

Role of postoperative radiotherapy in the treatment of Merkel tumours: experience at the Henri Mondor Hospital on 21 cases

International Nuclear Information System (INIS)

Calitchi, E.; Pan, Q.; Diana, C.; Belkacemi, Y.; Lagrange, J.L.

2010-01-01

As Merkel tumour treatment modalities are still a matter of discussion, the authors report the experience gained on 21 patients in the radiotherapy department of the Henri Mondor Hospital between 1990 and 2005. The treatment always comprised a surgical exeresis followed by radiotherapy. The authors analyse the obtained results which confirm the interest of postoperative radiotherapy. The detailed analysis of modalities (radiation type, total dose, irradiation volume) allows an optimal irradiation scheme to be proposed. Short communication

Therapeutic results and safety of postoperative radiotherapy for keloid after repeated Cesarean section in immediate postpartum period

International Nuclear Information System (INIS)

Kim Ju Ree; Lee, Sang Hoon

2012-01-01

To evaluate the effectiveness and safety of postoperative radiotherapy for the treatment of keloid scars administered immediately after Cesarean section. A total of 26 postpartum patients with confirmed keloids resulting from previous Cesarean sections received either 12 or 15 Gy radiotherapy. The radiotherapy was divided into three 6 MeV electron beam fractions administered during the postpartum period immediately following the fi nal Cesarean section. To evaluate ovarian safety, designated doses of radiation were estimated at the calculated depth of the ovaries using a solid plate phantom and an ionization chamber with the same lead cutout as was used for the treatment of Cesarean section operative scars and a tissue equivalent bolus. In total, the control rate was 77% (20 patients), while six (23%) developed focally elevated keloids (ranging from 0.5 to 2 cm in length) in the middle of the primary abdominal scar. Five patients experienced mild hyperpigmentation. Nonetheless, most patients (96%) were satisfied with the treatment results. The estimated percentage of the applied radiation doses that reached the calculated depth of the ovaries ranged from 0.0033% to 0.0062%. When administered during the immediate postpartum period, postoperative electron beam radiotherapy for repeated Cesarean section scars is generally safe and produces good cosmetic results with minimal toxicity.

Therapeutic results and safety of postoperative radiotherapy for keloid after repeated Cesarean section in immediate postpartum period

Energy Technology Data Exchange (ETDEWEB)

Kim Ju Ree; Lee, Sang Hoon [Cheil General Hospital and Women' s Healthcare Center, Kwandong University College of Medicine, Seoul (Korea, Republic of)

2012-06-15

To evaluate the effectiveness and safety of postoperative radiotherapy for the treatment of keloid scars administered immediately after Cesarean section. A total of 26 postpartum patients with confirmed keloids resulting from previous Cesarean sections received either 12 or 15 Gy radiotherapy. The radiotherapy was divided into three 6 MeV electron beam fractions administered during the postpartum period immediately following the fi nal Cesarean section. To evaluate ovarian safety, designated doses of radiation were estimated at the calculated depth of the ovaries using a solid plate phantom and an ionization chamber with the same lead cutout as was used for the treatment of Cesarean section operative scars and a tissue equivalent bolus. In total, the control rate was 77% (20 patients), while six (23%) developed focally elevated keloids (ranging from 0.5 to 2 cm in length) in the middle of the primary abdominal scar. Five patients experienced mild hyperpigmentation. Nonetheless, most patients (96%) were satisfied with the treatment results. The estimated percentage of the applied radiation doses that reached the calculated depth of the ovaries ranged from 0.0033% to 0.0062%. When administered during the immediate postpartum period, postoperative electron beam radiotherapy for repeated Cesarean section scars is generally safe and produces good cosmetic results with minimal toxicity.

Can a peri-rectal hydrogel spaceOAR programme for prostate cancer intensity-modulated radiotherapy be successfully implemented in a regional setting?

International Nuclear Information System (INIS)

Te Velde, Bridget L.; Westhuyzen, Justin; Wood, Maree; Shakespeare, Thomas P.; Awad, Nader

2017-01-01

The aim of this study was to investigate whether the implementation of a hydrogel spacer (SpaceOAR) programme for patients treated with 81 Gy prostate intensity-modulated radiotherapy (IMRT) in a regional setting can reduce rectal doses and toxicity. In this retrospective study, 125 patients with localised prostate cancer treated between April 2014 (programme commencement) and June 2015 were compared: 65 with SpaceOAR (inserted by five different urologists) and 60 patients treated over the same time period without SpaceOAR. Patients were treated with 81 Gy in 45Fx of IMRT over 9 weeks. Planning aims included restricting rectal doses to V40 Gy < 35%, V65 Gy < 17%, V75 Gy < 10%. Acute toxicity was assessed weekly during radiotherapy and at 12 weeks. Rectal volume parameters were all significantly lower in the SpaceOAR group, with an associated reduction in acute diarrhoea (13.8% vs 31.7%). There were no significant differences in the very low rates of acute and late faecal incontinence or proctitis, however, there was a trend towards increased haemorrhoid rate in the SpaceOAR group (11.7% vs 3.1%, P = 0.09). A SpaceOAR programme in a regional setting with urologists performing low volumes of insertions (<1 per month on average) is of clinical benefit, and was associated with significantly lower radiation doses to the rectum and lower rates of acute diarrhoea.

Concurrent Chemotherapy and Intensity-Modulated Radiotherapy for Locoregionally Advanced Laryngeal and Hypopharyngeal Cancers

International Nuclear Information System (INIS)

Lee, Nancy Y.; O'Meara, William; Chan, Kelvin; Della-Bianca, Cesar; Mechalakos, James G.; Zhung, Joanne; Wolden, Suzanne L.; Narayana, Ashwatha; Kraus, Dennis; Shah, Jatin P.; Pfister, David G.

2007-01-01

Purpose: To perform a retrospective review of laryngeal/hypopharyngeal carcinomas treated with concurrent chemotherapy and intensity-modulated radiotherapy (IMRT). Methods and Materials: Between January 2002 and June 2005, 20 laryngeal and 11 hypopharyngeal carcinoma patients underwent IMRT with concurrent platinum-based chemotherapy; most patients had Stage IV disease. The prescription of the planning target volume for gross, high-risk, and low-risk subclinical disease was 70, 59.4, and 54 Gy, respectively. Acute/late toxicities were retrospectively scored using the Common Toxicity Criteria scale. The 2-year local progression-free, regional progression-free, laryngectomy-free, distant metastasis-free, and overall survival rates were calculated using the Kaplan-Meier method. Results: The median follow-up of the living patients was 26 months (range, 17-58 months). The 2-year local progression-free, regional progression-free, laryngectomy-free, distant metastasis-free, and overall survival rate was 86%, 94%, 89%, 92%, and 63%, respectively. Grade 2 mucositis or higher occurred in 48% of patients, and all experienced Grade 2 or higher pharyngitis during treatment. Xerostomia continued to decrease over time from the end of RT, with none complaining of Grade 2 toxicity at this analysis. The 2-year post-treatment percutaneous endoscopic gastrostomy-dependency rate for those with hypopharyngeal and laryngeal tumors was 31% and 15%, respectively. The most severe late complications were laryngeal necrosis, necrotizing fascitis, and a carotid rupture resulting in death 3 weeks after salvage laryngectomy. Conclusion: These preliminary results have shown that IMRT achieved encouraging locoregional control of locoregionally advanced laryngeal and hypopharyngeal carcinomas. Xerostomia improved over time. Pharyngoesophageal stricture with percutaneous endoscopic gastrostomy dependency remains a problem, particularly for patients with hypopharyngeal carcinoma and, to a lesser

High-dose simultaneously integrated breast boost using intensity-modulated radiotherapy and inverse optimization

International Nuclear Information System (INIS)

Hurkmans, Coen W.; Meijer, Gert J.; Vliet-Vroegindeweij, Corine van; Sangen, Maurice J. van der; Cassee, Jorien

2006-01-01

Purpose: Recently a Phase III randomized trial has started comparing a boost of 16 Gy as part of whole-breast irradiation to a high boost of 26 Gy in young women. Our main aim was to develop an efficient simultaneously integrated boost (SIB) technique for the high-dose arm of the trial. Methods and Materials: Treatment planning was performed for 5 left-sided and 5 right-sided tumors. A tangential field intensity-modulated radiotherapy technique added to a sequentially planned 3-field boost (SEQ) was compared with a simultaneously planned technique (SIB) using inverse optimization. Normalized total dose (NTD)-corrected dose volume histogram parameters were calculated and compared. Results: The intended NTD was produced by 31 fractions of 1.66 Gy to the whole breast and 2.38 Gy to the boost volume. The average volume of the PTV-breast and PTV-boost receiving more than 95% of the prescribed dose was 97% or more for both techniques. Also, the mean lung dose and mean heart dose did not differ much between the techniques, with on average 3.5 Gy and 2.6 Gy for the SEQ and 3.8 Gy and 2.6 Gy for the SIB, respectively. However, the SIB resulted in a significantly more conformal irradiation of the PTV-boost. The volume of the PTV-breast, excluding the PTV-boost, receiving a dose higher than 95% of the boost dose could be reduced considerably using the SIB as compared with the SEQ from 129 cc (range, 48-262 cc) to 58 cc (range, 30-102 cc). Conclusions: A high-dose simultaneously integrated breast boost technique has been developed. The unwanted excessive dose to the breast was significantly reduced

Phase I Trial of Preoperative Hypofractionated Intensity-Modulated Radiotherapy with Incorporated Boost and Oral Capecitabine in Locally Advanced Rectal Cancer

International Nuclear Information System (INIS)

Freedman, Gary M.; Meropol, Neal J.; Sigurdson, Elin R.; Hoffman, John; Callahan, Elaine; Price, Robert; Cheng, Jonathan; Cohen, Steve; Lewis, Nancy; Watkins-Bruner, Deborah; Rogatko, Andre; Konski, Andre

2007-01-01

Purpose: To determine the safety and efficacy of preoperative hypofractionated radiotherapy using intensity-modulated radiotherapy (IMRT) and an incorporated boost with concurrent capecitabine in patients with locally advanced rectal cancer. Methods and Materials: The eligibility criteria included adenocarcinoma of the rectum, T3-T4 and/or N1-N2 disease, performance status 0 or 1, and age ≥18 years. Photon IMRT and an incorporated boost were used to treat the whole pelvis to 45 Gy and the gross tumor volume plus 2 cm to 55 Gy in 25 treatments within 5 weeks. The study was designed to escalate the dose to the gross tumor volume in 5-Gy increments in 3-patient cohorts. Capecitabine was given orally 825 mg/m 2 twice daily for 7 days each week during RT. The primary endpoint was the maximal tolerated radiation dose, and the secondary endpoints were the pathologic response and quality of life. Results: Eight patients completed RT at the initial dose level of 55 Gy. The study was discontinued because of toxicity-six Grade 3 toxicities occurred in 3 (38%) of 8 patients. All patients went on to definitive surgical resection, and no patient had a pathologically complete response. Conclusion: This regimen, using hypofractionated RT with an incorporated boost, had unacceptable toxicity despite using standard doses of capecitabine and IMRT. Additional research is needed to determine whether IMRT is able to reduce the side effects during and after pelvic RT with conventional dose fractionation

Change of tumor target volume during waiting time for intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Chen Bo; Yi Junlin; Gao Li; Xu Guozhen; Huang Xiaodong; Zhang Zhong; Luo Jingwei; Li Suyan

2007-01-01

Objective: To determine the influence of change in tumor target volume of nasopharyngeal carcinoma (NPC) while waiting for intensity modulated radiation therapy (IMRT). Methods: From March 2005 to December 2005, 31 patients with nasopharyngeal carcinoma received IMRT as the initial treatment at the Cancer Hospital of Chinese Academic of Medical Sciences. The original simulation CT scan was acquired before IMRT planning. A second CT scan was acquired before the start of radiotherapy. Wait- ing time was defined as the duration between CT simulation and start of radiotherapy. CT-CT fusion was used to minimize the error of delineation between the first tumor target volume (GTV) and the second tumor target volume (sGTV). Tumor target volume was calculated by treatment planning system. T test was carried out to analyse the difference between GTV and sGTV. Pearson correlation and multivariate linear regression was used to analyse the influence factor of the change betweent GTV and sGTV. Results: Median waiting time was 18 days (range, 9-27 days). There were significant differences between GTV and sGTV of both primary tumor (P=0.009) and metastatic lymphoma (P=0.005 ). Both Pearson correlation and multivariate linear regression showed that the change of primary tumor target volume had significant correlation with the first tumor target volume but had no significant correlation with the waiting time, sex, age, T stage and N stage (1992 Chinese Fuzhou Staging Classification). Conclusions: Within the range of the waiting time ob- served in our study, large volume primary tumor would have had a significant increase in volume, but whether the therapeutic effect would be influenced or not would need to be proved by study of large number of cases. Patients with large volume tumor should be considered to reduce the influence of waiting time by enlarging gross target volume and clinical targe volume and by neoadjuveant chemotherapy. For avoiding the unnecessary high-dose to normal

Intensity-Modulated Radiotherapy Reduces Gastrointestinal Toxicity in Patients Treated With Androgen Deprivation Therapy for Prostate Cancer

International Nuclear Information System (INIS)

Sharma, Navesh K.; Li Tianyu; Chen, David Y.; Pollack, Alan; Horwitz, Eric M.; Buyyounouski, Mark K.

2011-01-01

Purpose: Androgen deprivation therapy (AD) has been shown to increase late Grade 2 or greater rectal toxicity when used concurrently with three-dimensional conformal radiotherapy (3D-CRT). Intensity-modulated radiotherapy (IMRT) has the potential to reduce toxicity by limiting the radiation dose received by the bowel and bladder. The present study compared the genitourinary and gastrointestinal (GI) toxicity in men treated with 3D-CRT+AD vs. IMRT+AD. Methods and Materials: Between July 1992 and July 2004, 293 men underwent 3D-CRT (n = 170) or IMRT (n = 123) with concurrent AD (<6 months, n = 123; ≥6 months, n = 170). The median radiation dose was 76 Gy for 3D-CRT (International Commission on Radiation Units and Measurements) and 76 Gy for IMRT (95% to the planning target volume). Toxicity was assessed by a patient symptom questionnaire that was completed at each visit and recorded using a Fox Chase Modified Late Effects Normal Tissue Task radiation morbidity scale. Results: The mean follow-up was 86 months (standard deviation, 29.3) for the 3D-CRT group and 40 months (standard deviation, 9.7) for the IMRT group. Acute GI toxicity (odds ratio, 4; 95% confidence interval, 1.6-11.7; p = .005) was significantly greater with 3D-CRT than with IMRT and was independent of the AD duration (i.e., <6 vs. ≥6 months). The interval to the development of late GI toxicity was significantly longer in the IMRT group. The 5-year Kaplan-Meier estimate for Grade 2 or greater GI toxicity was 20% for 3D-CRT and 8% for IMRT (p = .01). On multivariate analysis, Grade 2 or greater late GI toxicity (hazard ratio, 2.1; 95% confidence interval, 1.1-4.3; p = .04) was more prevalent in the 3D-CRT patients. Conclusion: Compared with 3D-CRT, IMRT significantly decreased the acute and late GI toxicity in patients treated with AD.

Radical chemo-irradiation using intensity-modulated radiotherapy for locally advanced head and neck cancer in elderly patients: Experience from a tertiary care center in South India.

Science.gov (United States)

Chalissery, J R; Sudheeran, P C; Varghese, K M; Venkatesan, K

2016-01-01

To assess the feasibility, tolerance and response of radical chemo irradiation using Intensity modulated Radiotherapy [IMRT] in elderly patients [age >65] with locally advanced head and neck cancer. Patients aged 65 and above [range 65 to 84years] registered in oncology outpatient unit in our institution between December 2011 to 2014, with stage III and IV head and neck cancer were treated with radical dose of radiotherapy using IMRT and concurrent chemotherapy with cisplatin 40mg/sq.m weekly. Response evaluation and toxicity profile assessment was done 6 to 8 weeks after completion of treatment and 3 monthly thereafter with median follow up of 3 years. Total number of patients analysed were 47. 43(91.5%) patients tolerated 66-.70Gy of radiotherapy and 4 or more cycles of weekly chemotherapy with cisplatin. First follow up evaluation at 6 to 8 weeks showed 81% patients having complete loco regional response. Grade III skin reaction and mucositis was noticed in 24% and 47% respectively. No grade III neutropenia observed. Median follow up of 3 years showed a complete local control in 53% and overall survival of 60%. Radical chemo irradiation with IMRT in elderly patients is a feasible option. Long term local control and overall survival benefits needs to be followed up.

Gamma-H2Ax quantification of low dose irradiation-induced DNA damage in patients receiving intensity modulated radiotherapy (IRMT)

International Nuclear Information System (INIS)

Sivabalasingham, S.; Short, S.; Worku, M.; Marks, G.; Guerrero-Urbano, T.

2013-01-01

The full text of the publication follows. Purpose/Objective: IMRT (Intensity Modulated Radiotherapy) offers greater target dose compliance yet may produce a comparative higher whole body dose. The aim of this study is to quantify γH2Ax foci in lymphocytes (an established marker of DNA double strand breaks) in patients undergoing IMRT. Material/Methods: Radical inverse planned IMRT was delivered to patients with brain tumours. Peripheral blood samples were collected from each patient at the following time points: baseline; weekly- prior to and 30 minutes after one treatment fraction; 2 and 6 weeks following completion of treatment. Whole blood was centrifuged to separate lymphocytes, which were fixed and stained for fluorescent immunocytochemistry. 150 cells per sample were visualized. γH2Ax foci were identified and counted using confocal microscopy. Results A low basal level of foci was present in all samples prior to any radiation exposure (0.233, SD 0.028). There was a significant increase in mean foci per cell in post radiotherapy treatment samples(0.367 foci per cell pre-treatment and 0.612 foci per cell post treatment, p=0.000) and no significant difference between post-treatment foci numbers at different times during treatment(for example, 0.518 foci per cell at week 1 and 0.760 at week 6, p=0.279). Mean foci numbers returned to background levels at 6 weeks following completion of radiotherapy (0.239 foci per cell at baseline and 0.219 foci per cell at 6 weeks, p=0.529). Comparison between patients treated with different delivery methods is ongoing. Conclusion: γH2Ax is a feasible marker of DNA damage in lymphocytes during IMRT. These data demonstrate a reproducible level of foci induction in patients undergoing IMRT for tumour targets in brain. There is no significant accumulation of foci during treatment and foci numbers return to baseline post treatment. This assay may be useful to assess differences in whole body dose when different delivery methods

SU-E-T-394: The Use of Jaw Tracking in Intensity Modulated and Volumetric Modulated Arc Radiotherapy for Spine Stereotactic Radiosurgery

Energy Technology Data Exchange (ETDEWEB)

Chin, K; Wen, N; Huang, Y; Kim, J; Zhao, B; Siddiqui, S; Chetty, I; Ryu, S [Henry Ford Health System, Detroit, MI (United States)

2014-06-01

Purpose: To evaluate the potential advantages of jaw tracking for intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in spine radiosurgery. Methods: VMAT and IMRT plans were retrospectively generated for ten patients. Six plans for each patient were created in the Eclipse treatment planning system for a Varian Truebeam equipped with a Millennium 120 MLC. Plans were created to study IMRT and VMAT plans with and without jaw tracking, as well as IMRT plans of different flattening filter free (FFF) energies. Plans were prescribed to the 90% isodose line to 16 or 18 Gy in one fraction to cover 95% of the target. Planning target volume (PTV) coverage, conformity index (CI), dose to spinal cord, distance to fall off from the 90% to 50% isodose line (DTF), as well as delivery time were evaluated. Ion chamber and film measurements were performed to verify calculated and measured dose distributions. Results: Jaw tracking decreased the spinal cord dose for both IMRT and VMAT plans, but a larger decrease was seen with the IMRT plans (p=0.004 vs p=0.04). The average D10% for the spinal cord was least for the 6MV FFF IMRT plan with jaw tracking and was greatest for the 10MV FFF plan without jaw tracking. Treatment times between IMRT and VMAT plans with or without jaw tracking were not significantly different. Measured plans showed greater than 98.5% agreement for planar dose gamma analysis (3%/2 mm) and less than 2.5% for point dose analysis compared to calculated plans. Conclusion: Jaw tracking can be used to help decrease spinal cord dose without any change in treatment delivery or calculation accuracy. Lower dose to the spinal cord was achieved using 6 MV beams compared to 10 MV beams, though 10 MV may be justified in some cases to decrease skin dose.

Dosimetric comparison of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in total scalp irradiation: a single institutional experience