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.

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.

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

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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.

Patterns of failure in children with medulloblastoma treated with 3D conformal radiotherapy

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Skowronska-Gardas, Anna; Chojnacka, Marzanna; Morawska-Kaczynska, Marzena; Perek, Danuta; Perek-Polnik, Marta

2007-01-01

Background and purpose: Craniospinal irradiation for medulloblastoma is one of the most complex techniques employed in radiotherapy. Many reports stress the impact of irradiation quality on survival in these patients. Our report presents the outcome and patterns of failure for 95 patients treated with 3D conformal radiotherapy (3D-CRT). Materials and methods: From 1998 to 2003, 95 children with medulloblastoma received 3D conformal radiotherapy. All of them were previously treated with surgery and chemotherapy. The brain and upper spinal cord were treated with two lateral 6 MV photon fields. In four patients, the cribriform plate was irradiated by the additional field. For primary tumour bed we applied two or three photon beams. Spinal cord was irradiated either with 18-20 MeV electron fields or with a mixed beam. Results: With a median follow-up of 48 months, 32/95 patients suffered a multifocal (21) or isolated (11) recurrence. We evaluated every primary site of failure. In all patients, the recurrence appeared within the isodose level of 95-100%. Conclusions: Patterns of failure in medulloblastoma patients treated with 3D conformal radiotherapy indicated that the relapse was mainly associated with poor response to pre-irradiation chemotherapy. We believe that 3D conformal radiotherapy allows avoiding failures, related to radiotherapy uncertainties

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

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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.

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.

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.

Comparative dosimetric study of three-dimensional conformal, dynamic conformal arc, and intensity-modulated radiotherapy for brain tumor treatment using Novalis system

International Nuclear Information System (INIS)

Ding Meisong; Newman, Francis M.S.; Kavanagh, Brian D.; Stuhr, Kelly M.S.; Johnson, Tim K.; Gaspar, Laurie E.

2006-01-01

Purpose: To investigate the dosimetric differences among three-dimensional conformal radiotherapy (3D-CRT), dynamic conformal arc therapy (DCAT), and intensity-modulated radiotherapy (IMRT) for brain tumor treatment. Methods and Materials: Fifteen patients treated with Novalis were selected. We performed 3D-CRT, DCAT, and IMRT plans for all patients. The margin for the planning target volume (PTV) was 1 mm, and the specific prescription dose was 90% for all plans. The target coverage at the prescription dose, conformity index (CI), and heterogeneity index were analyzed for all plans. Results: For small tumors (PTV ≤2 cm 3 ), the three dosimetric parameters had approximate values for both 3D-CRT and DCAT plans. The CI for the IMRT plans was high. For medium tumors (PTV >2 to ≤100 cm 3 ), the three plans were competitive with each other. The IMRT plans had a greater CI, better target coverage at the prescription dose, and a better heterogeneity index. For large tumors (PTV >100 cm 3 ), the IMRT plan had good target coverage at the prescription dose and heterogeneity index and approximate CI values as those in the 3D-CRT and DCAT plans. Conclusion: The results of our study have shown that DCAT is suitable for most cases in the treatment of brain tumors. For a small target, 3D-CRT is useful, and IMRT is not recommended. For larger tumors, IMRT is superior to 3D-CRT and very competitive in sparing critical structures, especially for big tumors

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

Effects of three-dimensional conformal radiotherapy, indensity modulated radiotherapy, and conventional radiotherapy ON treatment of esophageal cancer

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Jian-Jun Han

2016-07-01

Full Text Available Objective: To compare the irradiation volume, short-term and long-term efficacy of conventional radiotherapy (CR, three-dimensional conformal radiotherapy (3D-CRT, and indensity modulated radiotherapy (IMRT in the treatment of esophageal cancer. Methods: A retrospective analysis method was adopted. The patients were divided into CR group (n=42, 3D-CRT group (n=45, and IMRT group (n=40. A follow-up visit was paid to collect the short-term and long-term efficacy, and the occurrence of adverse reactions. The gross tumor voluem (GTV, clinical target volume (CTV, planning target volume (PTV, and irradiation volume of organs (bilateral lungs, spinal cord, and heart at risk (OAR in the three groups were compared. Results: It was found by target volume comparison that the mean values of GTV, CTV, and PTV in the three groups were significantly increased (P0.05. The occurrence rate of adverse reactions in 3D-CRT group and IMRT group was significantly lower than that in CR group (P0.05. The difference of 1-year survival rate among the three groups was not statistically significant (P=0.144, but 3-year and 5-year survival rates in 3D-CRT group and IMRT group were significantly higher than those in CR group (P<0.05. Conclusions: 3D-CRT and IMRT can significantly enhance the short-term and long-term efficacy for esophageal cancer patients, and alleviate the radioactive damage; therefore, they are deserved to be widely recommended in the clinic.

Dosimetric comparison between intensity-modulated with coplanar field and 3D conformal radiotherapy with noncoplanar field for postocular invasion tumor.

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Wenyong, Tu; Lu, Liu; Jun, Zeng; Weidong, Yin; Yun, Li

2010-01-01

This study presents a dosimetric optimization effort aiming to compare noncoplanar field (NCF) on 3 dimensions conformal radiotherapy (3D-CRT) and coplanar field (CF) on intensity-modulated radiotherapy (IMRT) planning for postocular invasion tumor. We performed a planning study on the computed tomography data of 8 consecutive patients with localized postocular invasion tumor. Four fields NCF 3D-CRT in the transverse plane with gantry angles of 0-10 degrees , 30-45 degrees , 240-270 degrees , and 310-335 degrees degrees were isocentered at the center of gravity of the target volume. The geometry of the beams was determined by beam's eye view. The same constraints were prepared with between CF IMRT optimization and NCF 3D-CRT treatment. The maximum point doses (D max) for the different optic pathway structures (OPS) with NCF 3D-CRT treatment should differ in no more than 3% from those with the NCF IMRT plan. Dose-volume histograms (DVHs) were obtained for all targets and organ at risk (OAR) with both treatment techniques. Plans with NCF 3D-CRT and CF IMRT constraints on target dose in homogeneity were computed, as well as the conformity index (CI) and homogeneity index (HI) in the target volume. The PTV coverage was optimal with both NCF 3D-CRT and CF IMRT plans in the 8 tumor sites. No difference was noted between the two techniques for the average D(max) and D(min) dose. NCF 3D-CRT and CF IMRT will yield similar results on CI. However, HI was a significant difference between NCF 3D-CRT and CF IMRT plan (p 3D-CRT versus CF IMRT set-up is very slight. NCF3D-CRT is one of the treatment options for postocular invasion tumor. However, constraints for OARs are needed. 2010 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Dosimetric Comparison Between Intensity-Modulated with Coplanar Field and 3D Conformal Radiotherapy with Noncoplanar Field for Postocular Invasion Tumor

International Nuclear Information System (INIS)

Tu Wenyong; Liu Lu; Zeng Jun; Yin Weidong; Li Yun

2010-01-01

This study presents a dosimetric optimization effort aiming to compare noncoplanar field (NCF) on 3 dimensions conformal radiotherapy (3D-CRT) and coplanar field (CF) on intensity-modulated radiotherapy (IMRT) planning for postocular invasion tumor. We performed a planning study on the computed tomography data of 8 consecutive patients with localized postocular invasion tumor. Four fields NCF 3D-CRT in the transverse plane with gantry angles of 0-10 deg., 30-45 deg., 240-270 deg., and 310-335 deg. degrees were isocentered at the center of gravity of the target volume. The geometry of the beams was determined by beam's eye view. The same constraints were prepared with between CF IMRT optimization and NCF 3D-CRT treatment. The maximum point doses (D max) for the different optic pathway structures (OPS) with NCF 3D-CRT treatment should differ in no more than 3% from those with the NCF IMRT plan. Dose-volume histograms (DVHs) were obtained for all targets and organ at risk (OAR) with both treatment techniques. Plans with NCF 3D-CRT and CF IMRT constraints on target dose in homogeneity were computed, as well as the conformity index (CI) and homogeneity index (HI) in the target volume. The PTV coverage was optimal with both NCF 3D-CRT and CF IMRT plans in the 8 tumor sites. No difference was noted between the two techniques for the average D max and D min dose. NCF 3D-CRT and CF IMRT will yield similar results on CI. However, HI was a significant difference between NCF 3D-CRT and CF IMRT plan (p < 0.001). Physical endpoints for target showed the mean target dose to be low in the CF IMRT plan, caused by a large target dose in homogeneity (p < 0.001). The impact of NCF 3D-CRT versus CF IMRT set-up is very slight. NCF3D-CRT is one of the treatment options for postocular invasion tumor. However, constraints for OARs are needed.

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

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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-CRT

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

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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.

Prone Hypofractionated Whole-Breast Radiotherapy Without a Boost to the Tumor Bed: Comparable Toxicity of IMRT Versus a 3D Conformal Technique

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Hardee, Matthew E.; Raza, Shahzad; Becker, Stewart J.; Jozsef, Gabor; Lymberis, Stella C. [Department of Radiation Oncology, New York University School of Medicine, New York, NY (United States); Hochman, Tsivia; Goldberg, Judith D. [Division of Biostatistics, New York University School of Medicine, New York, NY (United States); DeWyngaert, Keith J. [Department of Radiation Oncology, New York University School of Medicine, New York, NY (United States); Formenti, Silvia C., E-mail: silvia.formenti@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, New York, NY (United States)

2012-03-01

Purpose: We report a comparison of the dosimetry and toxicity of three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT) among patients treated in the prone position with the same fractionation and target of the hypofractionation arm of the Canadian/Whelan trial. Methods and Materials: An institutional review board-approved protocol identified a consecutive series of early-stage breast cancer patients treated according to the Canadian hypofractionation regimen but in the prone position. Patients underwent IMRT treatment planning and treatment if the insurance carrier approved reimbursement for IMRT; in case of refusal, a 3D-CRT plan was used. A comparison of the dosimetric and toxicity outcomes during the acute, subacute, and long-term follow-up of the two treatment groups is reported. Results: We included 97 consecutive patients with 100 treatment plans in this study (3 patients with bilateral breast cancer); 40 patients were treated with 3D-CRT and 57 with IMRT. IMRT significantly reduced the maximum dose (Dmax median, 109.96% for 3D-CRT vs. 107.28% for IMRT; p < 0.0001, Wilcoxon test) and improved median dose homogeneity (median, 1.15 for 3D-CRT vs. 1.05 for IMRT; p < 0.0001, Wilcoxon test) when compared with 3D-CRT. Acute toxicity consisted primarily of Grade 1 to 2 dermatitis and occurred in 92% of patients. Grade 2 dermatitis occurred in 13% of patients in the 3D-CRT group and 2% in the IMRT group. IMRT moderately decreased rates of acute pruritus (p = 0.03, chi-square test) and Grade 2 to 3 subacute hyperpigmentation (p = 0.01, Fisher exact test). With a minimum of 6 months' follow-up, the treatment was similarly well tolerated in either group, including among women with large breast volumes. Conclusion: Hypofractionated breast radiotherapy is well tolerated when treating patients in the prone position, even among those with large breast volumes. Breast IMRT significantly improves dosimetry but yields only a modest

Comparison of dose distribution between 3DCRT and IMRT in middle thoracic and under thoracic esophageal carcinoma

International Nuclear Information System (INIS)

Li Dingjie; Liu Hailong; Mao Ronghu; Liu Ru; Guo Xiaoqi; Lei Hongchang; Wang Jianhua

2011-01-01

Objective: To compare the dose distribution between three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) in treating esophageal carcinoma (middle thoracic section and under thoracic section) and to select reasonable treatment methods for esophagus cancer. Methods: Ten cases with cancer of the middle thoracic section and under thoracic section esophagus were chosen for a retrospective treatment-planning study. 3DCRT and IMRT plans were created for each patient: Some critical indicators were evolved in evaluating the treatment plans of IMRT (5B and 7B) and 3DCRT (3B), such as, PTV coverage and dose-volumes to irradiated normal structures. Evaluation indicators: prescription of 50 Gy. total lung volume (V5, V10, V20), mean lung dose (MLD), spinal cord (Dmax), heart (V40) and conformality index (CI). Each plan was evaluated with respect to dose distribution,dose-volume histograms (DVHs), and additional dosimetric endpoints described below. Results: There is no significance of CRT and IMRT technique in protection of total lung volume,mean lung dose, spinal cord (Dmax), target, CI and heart. Conclusion: As To radiotherapy of esophagus cancer of the middle thoracic section and under thoracic section, IMRT has no advantage compared with 3DCRT, the selection of plan should be adapted to the situations of every patient. (authors)

Persistently better treatment planning results of intensity-modulated (IMRT) over conformal radiotherapy (3D-CRT) in prostate cancer patients with significant variation of clinical target volume and/or organs-at-risk

International Nuclear Information System (INIS)

Fenoglietto, Pascal; Laliberte, Benoit; Allaw, Ali; Ailleres, Norbert; Idri, Katia; Hay, Meng Huor; Moscardo, Carmen Llacer; Gourgou, Sophie; Dubois, Jean-Bernard; Azria, David

2008-01-01

Purpose: To compare the dose coverage of planning and clinical target volume (PTV, CTV), and organs-at-risk (OAR) between intensity-modulated (3D-IMRT) and conventional conformal radiotherapy (3D-CRT) before and after internal organ variation in prostate cancer. Methods and materials: We selected 10 patients with clinically significant interfraction volume changes. Patients were treated with 3D-IMRT to 80 Gy (minimum PTV dose of 76 Gy, excluding rectum). Fictitious, equivalent 3D-CRT plans (80 Gy at isocenter, with 95% isodose (76 Gy) coverage of PTV, with rectal blocking above 76 Gy) were generated using the same planning CT data set ('CT planning'). The plans were then also applied to a verification CT scan ('CT verify') obtained at a different moment. PTV, CTV, and OAR dose coverage were compared using non-parametric tests statistics for V95, V90 (% of the volume receiving ≥95 or 90% of the dose) and D50 (dose to 50% of the volume). Results: Mean V95 of the PTV for 'CT planning' was 94.3% (range, 88-99) vs 89.1% (range, 84-94.5) for 3D-IMRT and 3D-CRT (p = 0.005), respectively. Mean V95 of the CTV for 'CT verify' was 97% for both 3D-IMRT and 3D-CRT. Mean D50 of the rectum for 'CT planning' was 26.8 Gy (range, 22-35) vs 43.5 Gy (range, 33.5-50.5) for 3D-IMRT and 3D-CRT (p = 0.0002), respectively. For 'CT verify', this D50 was 31.1 Gy (range, 16.5-44) vs 44.2 Gy (range, 34-55) for 3D-IMRT and 3D-CRT (p = 0.006), respectively. V95 of the rectum was 0% for both plans for 'CT planning', and 2.3% (3D-IMRT) vs 2.1% (3D-CRT) for 'CT verify' (p = non-sig.). Conclusion: Dose coverage of the PTV and OAR was better with 3D-IMRT for each patient and remained so after internal volume changes

Comparison of radiotherapy dosimetry for 3D-CRT, IMRT, and SBRT based on electron density calibration

International Nuclear Information System (INIS)

Kartutik, K; Pawiro, S A; Wibowo, W E

2016-01-01

Accurate calculation of dose distribution affected by inhomogeneity tissue is required in radiotherapy planning. This study was performed to determine the ratio between radiotherapy planning using 3D-CRT, IMRT, and SBRT based on a calibrated curve of CT-number in the lung for different target's shape in 3D-CRT, IMRT, and spinal cord for SBRT. Calibration curves of CT-number were generated under measurement basis and introduced into TPS, then planning was performed for 3D-CRT, IMRT, and SBRT with 7, and 15 radiation fields. Afterwards, planning evaluation was performed by comparing the DVH curve, HI, and CI. 3D-CRT and IMRT produced the lowest HI at calibration curve of CIRS 002LFC with the value 0.24 and 10. Whereas SBRT produced the lowest HI on a linear calibration curve with a value of 0.361. The highest CI in IMRT and SBRT technique achieved using a linear calibration curve was 0.97 and 1.77 respectively. For 3D-CRT, the highest CI was obtained by using calibration curve of CIRS 062M with the value of 0.45. From the results of CI and HI, it is concluded that the calibration curve of CT-number does not significantly differ with Schneider's calibrated curve, and inverse planning gives a better result than forward planning. (paper)

Factors of influence on acute skin toxicity of breast cancer patients treated with standard three-dimensional conformal radiotherapy (3D-CRT) after breast conserving surgery (BCS)

International Nuclear Information System (INIS)

Kraus-Tiefenbacher, Uta; Sfintizky, Andreas; Welzel, Grit; Simeonova, Anna; Sperk, Elena; Siebenlist, Kerstin; Mai, Sabine; Wenz, Frederik

2012-01-01

Standard 3D-CRT after BCS may cause skin toxicity with a wide range of intensity including acute effects like erythema or late effects. In order to reduce these side effects it is mandatory to identify potential factors of influence in breast cancer patients undergoing standard three-dimensional conformal radiation therapy (3D-CRT) of the breast and modern systemic therapy. Between 2006 and 2010 a total of 211 breast cancer patients (median age 52,4 years, range 24–77) after BCS consecutively treated in our institution with 3D-CRT (50 Gy whole breast photon radiotherapy followed by 16 Gy electron boost to the tumorbed) were evaluated with special focus on documented skin toxicity at the end of the 50 Gy-course. Standardized photodocumentation of the treated breast was done in each patient lying on the linac table with arms elevated. Skin toxicity was documented according to the common toxicity criteria (CTC)-score. Potential influencing factors were classified in three groups: patient-specific (smoking, age, breast size, body mass index = BMI, allergies), tumor-specific (tumorsize) and treatment-specific factors (antihormonal therapy with tamoxifen or aromatase inhibitors, chemotherapy). Uni- and multivariate statistical analyses were done using IBM SPSS version 19. After 50 Gy 3D-CRT to the whole breast 28.9% of all 211 patients had no erythema, 62.2% showed erythema grade 1 (G1) and 8.5% erythema grade 2. None of the patients had grade 3/4 (G3/4) erythema. In univariate analyses a significant influence or trend on the development of acute skin toxicities (erythema G0 versus G1 versus G2) was observed for larger breast volumes (p=0,004), smoking during radiation therapy (p=0,064) and absence of allergies (p=0,014) as well as larger tumorsize (p=0,009) and antihormonal therapy (p=0.005). Neither patient age, BMI nor choice of chemotherapy showed any significant effect on higher grade toxicity. In the multivariate analysis, factors associated with higher grade

Risk of isolated nodal failure for non-small cell lung cancer (NSCLC) treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT) techniques--a retrospective analysis.

Science.gov (United States)

Kepka, Lucyna; Bujko, Krzysztof; Zolciak-Siwinska, Agnieszka

2008-01-01

To estimate retrospectively the rate of isolated nodal failures (INF) in NSCLC patients treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT). One hundred and eighty-five patients with I-IIIB stage treated with 3D-CRT in consecutive clinical trials differing in an extent of the ENI were analyzed. According to the extent of the ENI, two groups were distinguished: extended (n = 124) and limited (n = 61) ENI. INF was defined as regional nodal failure occurring without local progression. Cumulative Incidence of INF (CIINF) was evaluated by univariate and multivariate analysis with regard to prognostic factors. With a median follow up of 30 months, the two-year actuarial overall survival was 35%. The two-year CIINF rate was 12%. There were 16 (9%) INF, eight (6%) for extended and eight (13%) for limited ENI. In the univariate analysis bulky mediastinal disease (BMD), left side, higher N stage, and partial response to RT had a significant negative impact on the CIINF. BMD was the only independent predictor of the risk of incidence of the INF (p = 0.001). INF is more likely to occur in case of more advanced nodal status.

Skin-sparing Helical Tomotherapy vs 3D-conformal Radiotherapy for Adjuvant Breast Radiotherapy: In Vivo Skin Dosimetry Study

International Nuclear Information System (INIS)

Capelle, Lisa; Warkentin, Heather; MacKenzie, Marc; Joseph, Kurian; Gabos, Zsolt; Pervez, Nadeem; Tankel, Keith; Chafe, Susan; Amanie, John; Ghosh, Sunita; Parliament, Matthew; Abdulkarim, Bassam

2012-01-01

Purpose: We investigated whether treatment-planning system (TPS)-calculated dose accurately reflects skin dose received for patients receiving adjuvant breast radiotherapy (RT) with standard three-dimensional conformal RT (3D-CRT) or skin-sparing helical tomotherapy (HT). Methods and Materials: Fifty patients enrolled in a randomized controlled trial investigating acute skin toxicity from adjuvant breast RT with 3D-CRT compared to skin-sparing HT, where a 5-mm strip of ipsilateral breast skin was spared. Thermoluminescent dosimetry or optically stimulated luminescence measurements were made in multiple locations and were compared to TPS-calculated doses. Skin dosimetric parameters and acute skin toxicity were recorded in these patients. Results: With HT there was a significant correlation between calculated and measured dose in the medial and lateral ipsilateral breast (r = 0.67, P V50 (1.4% vs 5.9%, respectively; P=.001) but higher skin V40 and skin V30 (71.7% vs 64.0%, P=.02; and 99.0% vs 93.8%, P=.001, respectively) than 3D-CRT plans. Conclusion: The 3D-CRT TPS more accurately reflected skin dose than the HT TPS, which tended to overestimate dose received by 14% in patients receiving adjuvant breast RT.

IMRT vs. 2D-radiotherapy or 3D-conformal radiotherapy of nasopharyngeal carcinoma. Survival outcome in a Korean multi-institutional retrospective study (KROG 11-06)

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Moon, Sung Ho; Cho, Kwan Ho [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Ilsandong-gu, Goyang-si Gyeonggi-do (Korea, Republic of); Lee, Chang-Geol; Keum, Ki Chang [Yonsei University College of Medicine, Department of Radiation Oncology, Seodaemun-gu, Seoul (Korea, Republic of); Kim, Yeon-Sil [Seoul St. Mary' s Hospital, College of Medicine, the Catholic University of Korea, Department of Radiation Oncology, Seocho-gu, Seoul (Korea, Republic of); Wu, Hong-Gyun; Kim, Jin Ho [Seoul National University College of Medicine, Department of Radiation Oncology, Jongno-gu, Seoul (Korea, Republic of); Ahn, Yong Chan; Oh, Dongryul [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiation Oncology, Gangnam-gu, Seoul (Korea, Republic of); Lee, Jong Hoon [The Catholic University of Korea, College of Medicine, Department of Radiation Oncology, Paldal-gu, Suwon, Gyeonggi-do (Korea, Republic of)

2016-06-15

We compared treatment outcomes of two-dimensional radiotherapy (2D-RT), three-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC). In total, 1237 patients with cT1-4N0-3M0 NPC were retrospectively analyzed. Of these, 350, 390, and 497 were treated with 2D-RT, 3D-CRT, and IMRT, respectively. 3D-CRT and IMRT showed better 5-year overall survival (OS) rates (73.6 and 76.7 %, respectively) than did 2D-RT (5-year OS of 59.7 %, all p < 0.001). In T3-4 subgroup, IMRT was associated with a significantly better 5-year OS than was 2D-RT (70.7 vs. 50.4 %, respectively; p ≤ 0.001) and 3D-CRT (70.7 vs. 57.8 %, respectively; p = 0.011); however, the difference between the 2D-RT and 3D-CRT groups did not reach statistical significance (p = 0.063). In multivariate analyses of all patients, IMRT was a predictive factor for OS when compared with 2D-RT or 3D-CRT, as was 3D-CRT when compared with 2D-RT. Our study showed that 3D-CRT and IMRT were associated with a better local progression-free survival and OS than was 2D-RT in NPC. IMRT was significantly superior in terms of OS for advanced primary tumors (T3-4). (orig.) [German] Wir verglichen die Behandlungsergebnisse von zweidimensionaler Strahlentherapie (2D-RT), dreidimensionaler konformer Strahlentherapie (3D-CRT) und intensitaetsmodulierter Strahlentherapie (IMRT) bei Patienten mit Nasopharynxkarzinom (NPC). Insgesamt 1237 Patienten mit NPC im Stadium cT1-4/N0-3/M0 wurden rueckwirkend analysiert. Von diesen wurden jeweils 350, 390 und 497 mit 2D-RT, 3D-CRT und IMRT behandelt. 3D-CRT und IMRT zeigten eine bessere 5-Jahres-Gesamtueberlebensrate (5y-OS; jeweils 73,6 und 76,7%) als 2D-RT (59,7%; alle p < 0,001). In der Untergruppe T3-4 war die IMRT mit einer erheblich besseren 5y-OS verbunden als 2D-RT (jeweils 70,7 vs. 50,4%; p ≤ 0,001) und 3D-CRT (jeweils 70,7 vs. 57,8%; p = 0,011); jedoch gab es keinen Unterschied zwischen den Gruppen 2D

The value of 18F-FDG PET in three-dimensional conformal radiotherapy of cancer

International Nuclear Information System (INIS)

Lv Huiqing; Zhang Zhongmin; Lv Zhonghong

2006-01-01

Three-dimensional conformal radiotherapy (3D-CRT) is based on an extensive use of modern medical imaging techniques. Delineation of the gross tumor volume and organs at risk constitutes one of the most important phases of conformal radiotherapy procedures. 18 F-fluorodeoxyglucose ( 18 F-FDG) PET possesses greater sensitivity and accuracy in detecting diseased lymph nodes, is an important staging examination for patients considered for radiation treatment with curative intent. 18 F-FDG PET has an important role in delineation of gross tumor volume for patients treated with three-dimensional conformal radiotherapy. (authors)

Feasibility and efficacy of helical intensity-modulated radiotherapy for stage III non-small cell lung cancer in comparison with conventionally fractionated 3D-CRT.

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He, Jian; Huang, Yan; Chen, Yixing; Shi, Shiming; Ye, Luxi; Hu, Yong; Zhang, Jianying; Zeng, Zhaochong

2016-05-01

The standard treatment for stage III non-small-cell lung cancer (NSCLC) is still 60 Gy in conventional fractions combined with concurrent chemotherapy; however, the resulting local controls are disappointing. The aim of this study was to compare and assess the feasibility and efficacy of hypofractionated chemoradiotherapy using helical tomotherapy (HT) with conventional fractionation as opposed to using three-dimensional conformal radiotherapy (3D-CRT) for stage III NSCLC. Sixty-nine patients with stage III (AJCC 7th edition) NSCLC who underwent definitive radiation treatment at our institution between July 2011 and November 2013 were reviewed and analyzed retrospectively. A dose of 60 Gy in 20 fractions was delivered in the HT group (n=34), whereas 60 Gy in 30 fractions in the 3D-CRT group (n=35). Primary endpoints were toxicity, overall response rate, overall survival (OS) and progression-free survival (PFS). The median follow-up period was 26.4 months. V20 (P=0.005), V30 (P=0.001), V40 (P=0.004), mean lung dose (P=0.000) and max dose of spinal cord (P=0.005) were significantly lower in the HT group than in the 3D-CRT group. There was no significant difference in the incidences of acute radiation pneumonitis (RP) ≥ grade 2 between the two groups, whereas the incidences of acute radiation esophagitis ≥ grade 2 were significantly lower in the HT group than in the 3D-CRT group (P=0.027). Two-year overall response rate was significantly higher in the HT group than in the 3D-CRT group (P=0.015). One- and 2-year OS rates were significantly higher in the HT group (95.0% and 68.7%, respectively) than in the 3D-CRT group (85.5% and 47.6%, respectively; P=0.0236). One- and 2-year PFS rates were significantly higher in the HT group (57.8% and 26.3%, respectively) than in the 3D-CRT group (32.7% and 11.4%, respectively; P=0.0351). Univariate analysis indicated that performance status (PS), T stage and radiotherapy technique were significant prognostic factors for both OS

Does TomoDirect 3DCRT represent a suitable option for post-operative whole breast irradiation? A hypothesis-generating pilot study

International Nuclear Information System (INIS)

Borca, Valeria Casanova; La Porta, Maria Rosa; Cante, Domenico; Sciacero, Piera; Girelli, Giuseppe; Ricardi, Umberto; Tofani, Santi; Franco, Pierfrancesco; Catuzzo, Paola; Migliaccio, Fernanda; Zenone, Flora; Aimonetto, Stefania; Peruzzo, Andrea; Pasquino, Massimo; Russo, Giuliana

2012-01-01

This study investigates the use of TomoDirect TM 3DCRT for whole breast adjuvant radiotherapy (AWBRT) that represents a very attractive treatment opportunity, mainly for radiotherapy departments without conventional Linacs and only equipped with helical tomotherapy units. Plans were created for 17 breast cancer patients using TomoDirect in 3DCRT and IMRT modality and field-in-field 3DCRT planning (FIF) and compared in terms of PTV coverage, overdosage, homogeneity, conformality and dose to OARs. The possibility to define patient-class solutions for TD-3DCRT employment was investigated, correlating OARs dose constraints to patient specific anatomic parameters. TD-3DCRT showed PTV coverage and homogeneity significantly higher than TD-IMRT and FIF. PTV conformality was significantly better for FIF, while no differences were found between TD-3DCRT and TD-IMRT. TD-3DCRT showed mean values of the OARs dosimetric endpoints significantly higher than TD-IMRT; with respect to FIF, TD-3DCRT showed values significantly higher for lung V 20Gy , mean heart dose and V 25Gy , while contralateral lung maximum dose and contralateral breast mean dose resulted significantly lower. The Central Lung Distance (CLD) and the maximal Heart Distance (HD) resulted as useful clinical tools to predict the opportunity to employ TD-3DCRT: positive correlations were found between CLD and both V 20Gy and mean lung dose and between HD and both V 25Gy and the mean heart dose. TD-3DCRT showed a significantly shorter mean beam-on time than TD-IMRT. The present study showed that TD-3DCRT and TD-IMRT are two feasible and dosimetrically acceptable treatment approach for AWBRT, with an optimal PTV coverage and adequate OARs sparing. Some concerns might be raised in terms of dose to organs at risks if TD-3DCRT is applied to a general population. A correct patients clusterization according to simple quantitative anatomic measures, would help to correctly allocate patients to the appropriate treatment

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.

Risk of isolated nodal failure for non-small cell lung cancer (NSCLC) treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT) techniques - A retrospective analysis

International Nuclear Information System (INIS)

Kepka, Lucyna; Bujko, Krzysztof; Zolciak-Siwinska, Agnieszka

2008-01-01

Purpose. To estimate retrospectively the rate of isolated nodal failures (INF) in NSCLC patients treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT). Materials/methods. One hundred and eighty-five patients with I-IIIB stage treated with 3D-CRT in consecutive clinical trials differing in an extent of the ENI were analyzed. According to the extent of the ENI, two groups were distinguished: extended (n=124) and limited (n=61) ENI. INF was defined as regional nodal failure occurring without local progression. Cumulative Incidence of INF (CIINF) was evaluated by univariate and multivariate analysis with regard to prognostic factors. Results. With a median follow up of 30 months, the two-year actuarial overall survival was 35%. The two-year CIINF rate was 12%. There were 16 (9%) INF, eight (6%) for extended and eight (13%) for limited ENI. In the univariate analysis bulky mediastinal disease (BMD), left side, higher N stage, and partial response to RT had a significant negative impact on the CIINF. BMD was the only independent predictor of the risk of incidence of the INF (p=0.001). Conclusions. INF is more likely to occur in case of more advanced nodal status

Postoperative Radiotherapy for Prostate Cancer: A Comparison of Four Consensus Guidelines and Dosimetric Evaluation of 3D-CRT Versus Tomotherapy IMRT

International Nuclear Information System (INIS)

Malone, Shawn; Croke, Jennifer; Roustan-Delatour, Nicolas; Belanger, Eric; Avruch, Leonard; Malone, Colin; Morash, Christopher; Kayser, Cathleen; Underhill, Kathryn; Li Yan; Malone, Kyle; Nyiri, Balazs; Spaans, Johanna

2012-01-01

Purpose: Despite the benefits of adjuvant radiotherapy after radical prostatectomy, approximately one-half of patients relapse. Four consensus guidelines have been published (European Organization for Research and Treatment of Cancer, Faculty of Radiation Oncology Genito-Urinary Group, Princess Margaret Hospital, Radiation Therapy Oncology Group) with the aim of standardizing the clinical target volume (CTV) delineation and improve outcomes. To date, no attempt has been made to compare these guidelines in terms of treatment volumes or organ at risk (OAR) irradiation. The extent to which the guideline-derived plans meet the dosimetric constraints of present trials or of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) trial is also unknown. Our study also explored the dosimetric benefits of intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients treated with postoperative RT were included. The three-dimensional conformal radiotherapy (3D-CRT) plans were applied to cover the guideline-generated planning target volumes (66 Gy in 33 fractions). Dose–volume histograms (DVHs) were analyzed for CTV/planning target volume coverage and to evaluate OAR irradiation. The OAR DVHs were compared with the constraints proposed in the QUANTEC and Radiotherapy and Androgen Deprivation In Combination After Local Surgery (RADICALS) trials. 3D-CRT plans were compared with the tomotherapy plans for the Radiation Therapy Oncology Group planning target volume to evaluate the advantages of IMRT. Results: The CTV differed significantly between guidelines (p < 0.001). The European Organization for Research and Treatment of Cancer-CTVs were significantly smaller than the other CTVs (p < 0.001). Differences in prostate bed coverage superiorly accounted for the major volumetric differences between the guidelines. Using 3D-CRT, the DVHs rarely met the QUANTEC or RADICALS rectal constraints, independent of the guideline used. The RADICALS

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 Comparison of Three Dimensional Conformal Radiation Radiotherapy and Helical Tomotherapy Partial Breast Cancer

International Nuclear Information System (INIS)

Kim, Dae Woong; Kim, Jong Won; Choi, Yun Kyeong; Kim, Jung Soo; Hwang, Jae Woong; Jeong, Kyeong Sik; Choi, Gye Suk

2008-01-01

The goal of radiation treatment is to deliver a prescribed radiation dose to the target volume accurately while minimizing dose to normal tissues. In this paper, we comparing the dose distribution between three dimensional conformal radiation radiotherapy (3D-CRT) and helical tomotherapy (TOMO) plan for partial breast cancer. Twenty patients were included in the study, and plans for two techniques were developed for each patient (left breast:10 patients, right breast:10 patients). For each patient 3D-CRT planning was using pinnacle planning system, inverse plan was made using Tomotherapy Hi-Art system and using the same targets and optimization goals. We comparing the Homogeneity index (HI), Conformity index (CI) and sparing of the organs at risk for dose-volume histogram. Whereas the HI, CI of TOMO was significantly better than the other, 3D-CRT was observed to have significantly poorer HI, CI. The percentage ipsilateral non-PTV breast volume that was delivered 50% of the prescribed dose was 3D-CRT (mean: 40.4%), TOMO (mean: 18.3%). The average ipsilateral lung volume percentage receiving 20% of the PD was 3D-CRT (mean: 4.8%), TOMO (mean: 14.2), concerning the average heart volume receiving 20% and 10% of the PD during treatment of left breast cancer 3D-CRT (mean: 1.6%, 3.0%), TOMO (mean: 9.7%, 26.3%) In summary, 3D-CRT and TOMO techniques were found to have acceptable PTV coverage in our study. However, in TOMO, high conformity to the PTV and effective breast tissue sparing was achieved at the expense of considerable dose exposure to the lung and heart.

Dose distribution of IMRT and 3D-CRT on treating central non-small-cell lung cancer

International Nuclear Information System (INIS)

Zhu Xiaoyang; Yu Guangwei

2010-01-01

3D-CRT and IMRT were used in the radiation therapy of Central Non-small-cell lung cancer (NSCLC), and the dose difference of the methods was estimated. Thirty-two patients suffering with II class NSCLC were selected. Based on CT images, each patient was given 1 3D-CRT (3 dimensional conformal radiotherapy) and 2 IMRT(intensity modulated radiation therapy) treatment plans (5 fields and 7 fields), respectively, and the dose distribution was evaluated too. The results showed that PTVD mean and the PTV max , PTVD max (%) and CI of IMRT were both higher than those of 3D-CRT, but the uniformity was not as good as 3D-CRT. All indexes of lung and spinal cord treated with IMRT were lower than that treated with 3D-CRT. Moreover, there was no significance of the difference between 5 fields and 7 fields. In a conclusion, IMRT could not only decrease the target dose of NSCLC, but it can protect normal tissue from radiation damage effectively. And when IMRT was used, 5 fields might be enough. (authors)

Accelerated partial breast irradiation using robotic radiotherapy: a dosimetric comparison with tomotherapy and three-dimensional conformal radiotherapy.

Science.gov (United States)

Rault, Erwann; Lacornerie, Thomas; Dang, Hong-Phuong; Crop, Frederik; Lartigau, Eric; Reynaert, Nick; Pasquier, David

2016-02-27

Accelerated partial breast irradiation (APBI) is a new breast treatment modality aiming to reduce treatment time using hypo fractionation. Compared to conventional whole breast irradiation that takes 5 to 6 weeks, APBI is reported to induce worse cosmetic outcomes both when using three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT). These late normal tissue effects may be attributed to the dose volume effect because a large portion of the non-target breast tissue volume (NTBTV) receives a high dose. In the context of APBI, non-coplanar beams could spare the NTBTV more efficiently. This study evaluates the dosimetric benefit of using the Cyberknife (CK) for APBI in comparison to IMRT (Tomotherapy) and three dimensional conformal radiotherapy (3D-CRT). The possibility of using surgical clips, implanted during surgery, to track target movements is investigated first. A phantom of a female thorax was designed in-house using the measurements of 20 patients. Surgical clips of different sizes were inserted inside the breast. A treatment plan was delivered to the mobile and immobile phantom. The motion compensation accuracy was evaluated using three radiochromic films inserted inside the breast. Three dimensional conformal radiotherapy (3D-CRT), Tomotherapy (TOMO) and CK treatment plans were calculated for 10 consecutive patients who received APBI in Lille. To ensure a fair comparison of the three techniques, margins applied to the CTV were set to 10 mm. However, a second CK plan was prepared using 3 mm margins to evaluate the benefits of motion compensation. Only the larger clips (VITALITEC Medium-Large) could be tracked inside the larger breast (all gamma indices below 1 for 1 % of the maximum dose and 1 mm). All techniques meet the guidelines defined in the NSABP/RTOG and SHARE protocols. As the applied dose volume constraints are very strong, insignificant dosimetric differences exist between techniques regarding the PTV

Accelerated partial breast irradiation using robotic radiotherapy: a dosimetric comparison with tomotherapy and three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Rault, Erwann; Lacornerie, Thomas; Dang, Hong-Phuong; Crop, Frederik; Lartigau, Eric; Reynaert, Nick; Pasquier, David

2016-01-01

Accelerated partial breast irradiation (APBI) is a new breast treatment modality aiming to reduce treatment time using hypo fractionation. Compared to conventional whole breast irradiation that takes 5 to 6 weeks, APBI is reported to induce worse cosmetic outcomes both when using three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT). These late normal tissue effects may be attributed to the dose volume effect because a large portion of the non-target breast tissue volume (NTBTV) receives a high dose. In the context of APBI, non-coplanar beams could spare the NTBTV more efficiently. This study evaluates the dosimetric benefit of using the Cyberknife (CK) for APBI in comparison to IMRT (Tomotherapy) and three dimensional conformal radiotherapy (3D-CRT). The possibility of using surgical clips, implanted during surgery, to track target movements is investigated first. A phantom of a female thorax was designed in-house using the measurements of 20 patients. Surgical clips of different sizes were inserted inside the breast. A treatment plan was delivered to the mobile and immobile phantom. The motion compensation accuracy was evaluated using three radiochromic films inserted inside the breast. Three dimensional conformal radiotherapy (3D-CRT), Tomotherapy (TOMO) and CK treatment plans were calculated for 10 consecutive patients who received APBI in Lille. To ensure a fair comparison of the three techniques, margins applied to the CTV were set to 10 mm. However, a second CK plan was prepared using 3 mm margins to evaluate the benefits of motion compensation. Only the larger clips (VITALITEC Medium-Large) could be tracked inside the larger breast (all gamma indices below 1 for 1 % of the maximum dose and 1 mm). All techniques meet the guidelines defined in the NSABP/RTOG and SHARE protocols. As the applied dose volume constraints are very strong, insignificant dosimetric differences exist between techniques regarding the PTV

3-D conformal radiotherapy of localized prostate cancer: A subgroup analysis of rectoscopic findings prior to radiotherapy and acute/late rectal side effects

International Nuclear Information System (INIS)

Goldner, Gregor; Zimmermann, Frank; Feldmann, Horst; Glocker, Stefan; Wachter-Gerstner, Natascha; Geinitz, Hans; Becker, Gerd; Poetzi, Regina; Wambersie, Andre; Bamberg, Michael; Molls, Michael; Wachter, Stefan; Poetter, Richard

2006-01-01

Background and purpose: To identify endoscopic pathological findings prior to radiotherapy and a possible correlation with acute or chronic rectal side effects after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Patients and methods: Between 03/99 and 07/02, a total of 298 patients, who consented in a voluntary rectoscopy prior to radiotherapy were included into the analysis. Patients were treated with a total dose of either 70 or 74 Gy. Pathological rectoscopic findings like hemorrhoids, polyps or diverticula were documented. Acute and late rectal side effects were scored using the EORTC/RTOG score. Results: The most frequent pathological endosopic findings were hemorrhoids (35%), polyps (24%) and diverticula (13%). Rectal toxicity was mostly low to moderate. Grade 0/1 cumulative acute and late rectal side effects were 82 and 84%, grade 2 were 18 and 17%, respectively. We could not identify any correlation between preexisting pathological findings and rectal side effects by statistical analysis. Conclusions: There is no evidence that prostate cancer patients presenting with endoscopic verified pathological findings in the rectal mucosa at diagnosis are at an increased risk to develop rectal side effects when treated with 3D-CRT of the prostatic region

Tolerance and early outcome results of postprostatectomy three-dimensional conformal radiotherapy

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Zelefsky, Michael J.; Aschkenasy, Eric; Kelsen, Suzanne; Leibel, Steven A.

1997-01-01

Purpose: Three-dimensional conformal radiotherapy (3D-CRT) has been associated with a reduction in acute and late toxicity among patients treated for localized prostatic cancer. The purpose of this study is to assess the acute and late toxicity of 3D-CRT delivered to patients in the postprostatectomy setting and to analyze which factors predict for durable biochemical control in this group of patients. Methods and Materials: Between 1988 and 1994, 42 patients were treated after prostatectomy with three-dimensional conformal radiotherapy. The median time from prostatectomy to radiotherapy was 11 months. Indications for treatment included a rising serum PSA level in 28 patients (65%) and positive surgical margins without a rising PSA level in 14 (35%). Twenty-five patients (60%) had pathologic stage T3 disease, and 32 (74%) had tumor at or close to the surgical margins. The median dose was 64.8 Gy, and the median follow-up time was 2 years. Results: 3D-CRT in the postprostatectomy setting was well tolerated. Three patients (7%) experienced Grade II acute genitourinary toxicity and nine patients (21%) experienced Grade II acute gastrointestinal toxicity during treatment. No patient experienced Grade III or higher acute morbidity. The 2-year actuarial risk for Grade II late genitourinary and gastrointestinal late complications were 5 and 9%, respectively. In patients with existing incontinence, the incidence of worsening stress incontinence 6 months after treatment was 17%, which resolved within 12 months to its preradiotherapy level in four of six cases (66%). The overall 2-year postirradiation PSA relapse-free survival rate was 53%. The 2-year PSA relapse-free survival was 66% for patients with undetectable PSA levels in the immediate postoperative period compared to 26% for those with detectable levels of PSA after surgery (p 1.0 ng/ml (p 1 ng/ml (p < 0.002) was the most important covariate predicting for a rising PSA after radiotherapy. Conclusions: After

Therapeutic effect analysis of three dimensional conformal radiotherapy non-small cell lung cancer

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Yao Zhijun; Cao Yongzhen; Zhang Wenxue; Liang Feng

2012-01-01

Objective: To analyse the treatment effect of non-small cell lung cancer of three dimensional conformal radiotherapy (3D-CRT) and to study the effect of patient survival related factors. Methods: Retrospective analysis was mack for 136 cases of non-small cell lung cancer, all accept 3D-CRT, through the case data collection and long-term follow-up, using the single factor and multiple factor analysis survival time and its influencing factors. Results: The recent curative effects of 136 cases of patients with three dimensional conformal radiotherapy: Complete response (CR) 14.7% (20/136), partial response (PR) 60.3 (82/136), stable disease(SD) 19.9% (27/136), progression disease (PD) 5.1% (7/136), total effective rate is 75% (102/136). One, two, three, five year survival rate is 79.4%, 45.4%, 22.1%, 12.5%. Side effects: Class 1 radiated esophagitis 35 cases, Class 2 radiated esophagitis 16 cases, Class 3 and above radiated esophagitis 0 case. Class I radiated pneumonia 20 cases, Class 2 radiated pneumonia 9 cases, Class 3 radiated pneumonia 0 case. Single factor analysis shows the influence of gender, age, pathology, phase, dose, and first-phase curative effect to the survival time are of a statistical significance, Multiple factor analysis showed KPS score, phase, dose, first-phase curative effect are the survival time independent factors. Conclusion: 3D-CRT for patients with non-small cell lung carcinoma is a safe, effective treatment method, Side effects are relatively low, and the patients survival time is long after radiotherapy. (authors)

Comparing two strategies of dynamic intensity modulated radiation therapy (dIMRT with 3-dimensional conformal radiation therapy (3DCRT in the hypofractionated treatment of high-risk prostate cancer

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Yartsev Slav

2008-01-01

Full Text Available Abstract Background To compare two strategies of dynamic intensity modulated radiation therapy (dIMRT with 3-dimensional conformal radiation therapy (3DCRT in the setting of hypofractionated high-risk prostate cancer treatment. Methods 3DCRT and dIMRT/Helical Tomotherapy(HT planning with 10 CT datasets was undertaken to deliver 68 Gy in 25 fractions (prostate and simultaneously delivering 45 Gy in 25 fractions (pelvic lymph node targets in a single phase. The paradigms of pelvic vessel targeting (iliac vessels with margin are used to target pelvic nodes and conformal normal tissue avoidance (treated soft tissues of the pelvis while limiting dose to identified pelvic critical structures were assessed compared to 3DCRT controls. Both dIMRT/HT and 3DCRT solutions were compared to each other using repeated measures ANOVA and post-hoc paired t-tests. Results When compared to conformal pelvic vessel targeting, conformal normal tissue avoidance delivered more homogenous PTV delivery (2/2 t-test comparisons; p dose, 1–3 Gy over 5/10 dose points; p Conclusion dIMRT/HT nodal and pelvic targeting is superior to 3DCRT in dose delivery and critical structure sparing in the setting of hypofractionation for high-risk prostate cancer. The pelvic targeting paradigm is a potential solution to deliver highly conformal pelvic radiation treatment in the setting of nodal location uncertainty in prostate cancer and other pelvic malignancies.

Dosimetric Comparison Between 3DCRT and IMRT Using Different Multileaf Collimators in the Treatment of Brain Tumors

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Ding Meisong; Newman, Francis M.S.; Chen Changhu; Stuhr, Kelly; Gaspar, Laurie E.

2009-01-01

We investigated the differences between 3-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT), and the impact of collimator leaf-width on IMRT plans for the treatment of nonspherical brain tumors. Eight patients treated by 3DCRT with Novalis were selected. We developed 3 IMRT plans with different multileaf collimators (Novalis m3, Varian MLC-120, and Varian MLC-80) with the same treatment margins, number of beams, and gantry positions as in the 3DCRT treatment plans. Treatment planning utilized the BrainLAB treatment planning system. For each patient, the dose constraints and optimization parameters remained identical for all plans. The heterogeneity index, the percentage target coverage, critical structures, and normal tissue volumes receiving 50% of the prescription dose were calculated to compare the dosimetric difference. Equivalent uniform dose (EUD) and tumor control probability (TCP) were also introduced to evaluate the radiobiological effect for different plans. We found that IMRT significantly improved the target dose homogeneity compared to the 3DCRT. However, IMRT showed the same radiobiological effect as 3DCRT. For the brain tumors adjacent to (or partially overlapping with) critical structures, IMRT dramatically spared the volume of the critical structures to be irradiated. In IMRT plans, the smaller collimator leaf width could reduce the volume of critical structures irradiated to the 50% level for those partially overlapping with the brain tumors. For relatively large and spherical brain tumors, the smaller collimator leaf widths give no significant benefit

IMRT and 3D conformal radiotherapy with or without elective nodal irradiation in locally advanced NSCLC. A direct comparison of PET-based treatment planning

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Fleckenstein, Jochen; Kremp, Katharina; Kremp, Stephanie; Palm, Jan; Ruebe, Christian

2016-01-01

The potential of intensity-modulated radiation therapy (IMRT) as opposed to three-dimensional conformal radiotherapy (3D-CRT) is analyzed for two different concepts of fluorodeoxyglucose positron emission tomography (FDG PET)-based target volume delineation in locally advanced non-small cell lung cancer (LA-NSCLC): involved-field radiotherapy (IF-RT) vs. elective nodal irradiation (ENI). Treatment planning was performed for 41 patients with LA-NSCLC, using four different planning approaches (3D-CRT-IF, 3D-CRT-ENI, IMRT-IF, IMRT-ENI). ENI included a boost irradiation after 50 Gy. For each plan, maximum dose escalation was calculated based on prespecified normal tissue constraints. The maximum prescription dose (PD), tumor control probability (TCP), conformal indices (CI), and normal tissue complication probabilities (NTCP) were analyzed. IMRT resulted in statistically significant higher prescription doses for both target volume concepts as compared with 3D-CRT (ENI: 68.4 vs. 60.9 Gy, p < 0.001; IF: 74.3 vs. 70.1 Gy, p < 0.03). With IMRT-IF, a PD of at least 66 Gy was achieved for 95 % of all plans. For IF as compared with ENI, there was a considerable theoretical increase in TCP (IMRT: 27.3 vs. 17.7 %, p < 0.00001; 3D-CRT: 20.2 vs. 9.9 %, p < 0.00001). The esophageal NTCP showed a particularly good sparing with IMRT vs. 3D-CRT (ENI: 12.3 vs. 30.9 % p < 0.0001; IF: 15.9 vs. 24.1 %; p < 0.001). The IMRT technique and IF target volume delineation allow a significant dose escalation and an increase in TCP. IMRT results in an improved sparing of OARs as compared with 3D-CRT at equivalent dose levels. (orig.) [de

Comparing two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the hypofractionated treatment of high-risk prostate cancer

International Nuclear Information System (INIS)

Yuen, Jasper; Rodrigues, George; Trenka, Kristina; Coad, Terry; Yartsev, Slav; D'Souza, David; Lock, Michael; Bauman, Glenn

2008-01-01

To compare two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the setting of hypofractionated high-risk prostate cancer treatment. 3DCRT and dIMRT/Helical Tomotherapy(HT) planning with 10 CT datasets was undertaken to deliver 68 Gy in 25 fractions (prostate) and simultaneously delivering 45 Gy in 25 fractions (pelvic lymph node targets) in a single phase. The paradigms of pelvic vessel targeting (iliac vessels with margin are used to target pelvic nodes) and conformal normal tissue avoidance (treated soft tissues of the pelvis while limiting dose to identified pelvic critical structures) were assessed compared to 3DCRT controls. Both dIMRT/HT and 3DCRT solutions were compared to each other using repeated measures ANOVA and post-hoc paired t-tests. When compared to conformal pelvic vessel targeting, conformal normal tissue avoidance delivered more homogenous PTV delivery (2/2 t-test comparisons; p < 0.001), similar nodal coverage (8/8 t-test comparisons; p = ns), higher and more homogenous pelvic tissue dose (6/6 t-test comparisons; p < 0.03), at the cost of slightly higher critical structure dose (D dose , 1–3 Gy over 5/10 dose points; p < 0.03). The dIMRT/HT approaches were superior to 3DCRT in sparing organs at risk (22/24 t-test comparisons; p < 0.05). dIMRT/HT nodal and pelvic targeting is superior to 3DCRT in dose delivery and critical structure sparing in the setting of hypofractionation for high-risk prostate cancer. The pelvic targeting paradigm is a potential solution to deliver highly conformal pelvic radiation treatment in the setting of nodal location uncertainty in prostate cancer and other pelvic malignancies

Intensity-modulated radiotherapy (IMRT) and conventional three-dimensional conformal radiotherapy for high-grade gliomas: Does IMRT increase the integral dose to normal brain?

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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

IMRT and 3D conformal radiotherapy with or without elective nodal irradiation in locally advanced NSCLC: A direct comparison of PET-based treatment planning.

Science.gov (United States)

Fleckenstein, Jochen; Kremp, Katharina; Kremp, Stephanie; Palm, Jan; Rübe, Christian

2016-02-01

The potential of intensity-modulated radiation therapy (IMRT) as opposed to three-dimensional conformal radiotherapy (3D-CRT) is analyzed for two different concepts of fluorodeoxyglucose positron emission tomography (FDG PET)-based target volume delineation in locally advanced non-small cell lung cancer (LA-NSCLC): involved-field radiotherapy (IF-RT) vs. elective nodal irradiation (ENI). Treatment planning was performed for 41 patients with LA-NSCLC, using four different planning approaches (3D-CRT-IF, 3D-CRT-ENI, IMRT-IF, IMRT-ENI). ENI included a boost irradiation after 50 Gy. For each plan, maximum dose escalation was calculated based on prespecified normal tissue constraints. The maximum prescription dose (PD), tumor control probability (TCP), conformal indices (CI), and normal tissue complication probabilities (NTCP) were analyzed. IMRT resulted in statistically significant higher prescription doses for both target volume concepts as compared with 3D-CRT (ENI: 68.4 vs. 60.9 Gy, p ENI, there was a considerable theoretical increase in TCP (IMRT: 27.3 vs. 17.7 %, p ENI: 12.3 vs. 30.9 % p < 0.0001; IF: 15.9 vs. 24.1 %; p < 0.001). The IMRT technique and IF target volume delineation allow a significant dose escalation and an increase in TCP. IMRT results in an improved sparing of OARs as compared with 3D-CRT at equivalent dose levels.

Parotid gland sparing radiotherapy technique using 3-D conformal radiotherapy for nasopharyngeal carcinoma

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Lim, Ji Hoon; Kim, Gwi Eon; Keum, Ki Chang; Suh, Chang Ok; Lee, Sang Wook; Park, Hee Chul; Cho, Jae Ho; Chang, Sei Kyung; Loh, Juhn Kyu

2000-01-01

Although using the high energy photon beam with conventional parallel-opposed beams radio-therapy for nasopgaryngeal carcinoma, radiation-induced xerostomia is a troublesome problem for patients. We conducted this study to explore a new parotid gland sparing technique in 3-D conformal radiotherapy (3-DCRT) in an effort to prevent the radiation-induced xerostomia. We performed three different planning for four clinically node-negative nasopharyngeal cancer patients with different location of tumor(intracranial extension, nasal cavity extension, oropharyngeal extension, parapharyngeal extension), and intercompared the plans. Total prescription dose was 70.2 Gy to the isocenter. For plan-A, 2-D parallel opposing fields, a conventional radiotherapy technique, were employed. For plan-B, 2-D parallel opposing fields were used up until 54 Gy and afterwards 3-D non-coplanar beams were used. For plan-C, the new technique, 54Gy was delivered by 3-D conformal 3-port beams (AP and both lateral ports with wedge compensator, shielding both superficial lobes of parotid glands at the AP beam using BEV) from the beginning of the treatment and early spinal cord block (at 36 Gy) was performed. And bilateral posterior necks were treated with electron after 36 Gy. After 54 Gy, non-coplanar beams were used for cone-down plan. We intercompared dose statistics (Dmax, Dmin, Dmean, D95, D05, V95, V05, Volume receiving 46 Gy) and dose volume histograms (DVH) of tumor and normal tissues and NTCP values of parotid glands for the above three plans. For all patients, the new technique (plan-C) was comparable or superior to the other plans in target volume isodose distribution and dose statistics and it has more homogenous target volume coverage. The new technique was most superior to the other plans in parotid glands sparing (volume receiving 46 Gy: 100, 98, 69% for each plan-A, B and C). And it showed the lowest NTCP value of parotid glands in all patients (range of NTCP; 96-100%, 79-99%, 51

A dosimetric comparison of 3D conformal vs intensity modulated vs volumetric arc radiation therapy for muscle invasive bladder cancer

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Foroudi Farshad

2012-07-01

Full Text Available Abstract Background To compare 3 Dimensional Conformal radiotherapy (3D-CRT with Intensity Modulated Radiotherapy (IMRT with Volumetric-Modulated Arc Therapy (VMAT for bladder cancer. Methods Radiotherapy plans for 15 patients with T2-T4N0M0 bladder cancer were prospectively developed for 3-DCRT, IMRT and VMAT using Varian Eclipse planning system. The same radiation therapist carried out all planning and the same clinical dosimetric constraints were used. 10 of the patients with well localised tumours had a simultaneous infield boost (SIB of the primary tumour planned for both IMRT and VMAT. Tumour control probabilities and normal tissue complication probabilities were calculated. Results Mean planning time for 3D-CRT, IMRT and VMAT was 30.0, 49.3, and 141.0 minutes respectively. The mean PTV conformity (CI index for 3D-CRT was 1.32, for IMRT 1.05, and for VMAT 1.05. The PTV Homogeneity (HI index was 0.080 for 3D-CRT, 0.073 for IMRT and 0.086 for VMAT. Tumour control and normal tissue complication probabilities were similar for 3D-CRT, IMRT and VMAT. The mean monitor units were 267 (range 250–293 for 3D-CRT; 824 (range 641–1083 for IMRT; and 403 (range 333–489 for VMAT (P  Conclusions VMAT is associated with similar dosimetric advantages as IMRT over 3D-CRT for muscle invasive bladder cancer. VMAT is associated with faster delivery times and less number of mean monitor units than IMRT. SIB is feasible in selected patients with localized tumours.

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

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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

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

Biological Modeling Based Outcome Analysis (BMOA) in 3D Conformal Radiation Therapy (3DCRT) Treatments for Lung and Breast Cancers

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Pyakuryal, Anil; Chen, Chiu-Hao; Dhungana, Sudarshan

2010-03-01

3DCRT treatments are the most commonly used techniques in the treatment of lung and breast cancers. The purpose of this study was to perform the BMOA of the 3DCRT plans designed for the treatment of breast and lung cancers utilizing HART program (Med. Phys. 36, p.2547(2009)). The BMOA parameters include normal tissue complication probability (NTCP), tumor control probability (TCP), and the complication-free tumor control probability (P+). The 3DCRT plans were designed for (i) the palliative treatment of 8 left lung cancer patients (CPs) at early stage (m=8), (ii) the curative treatment of 8 left lung CPs at stages II and III (k=8), and (iii) the curative treatment of 8 left breast CPs (n=8). The NTCPs were noticeably small (esophagus in lung CPs (k=8). Assessments of the TCPs and P+s also indicated good improvements in local tumor control in all plans. Homogeneous target coverage and improved dose conformality were the major advantages of such techniques in the treatment of breast cancer. These achievements support the efficacy of the 3DCRT techniques for the efficient treatment of various types of cancer.

Three-year outcomes of a once daily fractionation scheme for accelerated partial breast irradiation (APBI) using 3-D conformal radiotherapy (3D-CRT)

International Nuclear Information System (INIS)

Goyal, Sharad; Daroui, Parima; Khan, Atif J; Kearney, Thomas; Kirstein, Laurie; Haffty, Bruce G

2013-01-01

The aim of this study was to report 3-year outcomes of toxicity, cosmesis, and local control using a once daily fractionation scheme (49.95 Gy in 3.33 Gy once daily fractions) for accelerated partial breast irradiation (APBI) using three-dimensional conformal radiotherapy (3D-CRT). Between July 2008 and August 2010, women aged ≥40 years with ductal carcinoma in situ or node-negative invasive breast cancer ≤3 cm in diameter, treated with breast-conserving surgery achieving negative margins, were accrued to a prospective study. Women were treated with APBI using 3–5 photon beams, delivering 49.95 Gy over 15 once daily fractions over 3 weeks. Patients were assessed for toxicities, cosmesis, and local control rates before APBI and at specified time points. Thirty-four patients (mean age 60 years) with Tis 0 (n = 9) and T1N0 (n = 25) breast cancer were treated and followed up for an average of 39 months. Only 3% (1/34) patients experienced a grade 3 subcutaneous fibrosis and breast edema and 97% of the patients had good/excellent cosmetic outcome at 3 years. The 3-year rate of ipsilateral breast tumor recurrence (IBTR) was 0% while the rate of contralateral breast events was 6%. The 3-year disease-free survival (DFS), overall survival (OS), and breast cancer-specific survival (BCSS) was 94%, 100%, and 100%, respectively. Our novel accelerated partial breast fractionation scheme of 15 once daily fractions of 3.33 Gy (49.95 Gy total) is a remarkably well-tolerated regimen of 3D-CRT-based APBI. A larger cohort of patients is needed to further ascertain the toxicity of this accelerated partial breast regimen

Conkiss: Conformal Kidneys Sparing 3D Noncoplanar Radiotherapy Treatment for Pancreatic Cancer As an Alternative to IMRT

International Nuclear Information System (INIS)

Sebestyen, Zsolt; Kovacs, Peter; Gulyban, Akos; Farkas, Robert; Bellyei, Szabolcs; Liposits, Gabor; Szigeti, Andras; Esik, Olga; Derczy, Katalin; Mangel, Laszlo

2011-01-01

When treating pancreatic cancer using standard (ST) 3D conformal radiotherapy (3D-CRT) beam arrangements, the kidneys often receive a higher dose than their probable tolerance limit. Our aim was to elaborate a new planning method that-similarly to IMRT-effectively spares the kidneys without compromising the target coverage. Conformal kidneys sparing (CONKISS) 5-field, noncoplanar plans were compared with ST plans for 23 consecutive patients retrospectively. Optimal beam arrangements were used consisting of a left- and right-wedged beam-pair and an anteroposterior beam inclined in the caudal direction. The wedge direction determination (WEDDE) algorithm was developed to adjust the adequate direction of wedges. The aimed organs at risk (OARs) mean dose limits were: kidney <12 Gy, liver <25 Gy, small bowels <30 Gy, and spinal cord maximum <45 Gy. Conformity and homogeneity indexes with z-test were used to evaluate and compare the different planning approaches. The mean dose to the kidneys decreased significantly (p < 0.05): left kidney 7.7 vs. 10.7 Gy, right kidney 9.1 vs. 11.7 Gy. Meanwhile the mean dose to the liver increased significantly (18.1 vs. 15.0 Gy). The changes in the conformity, homogeneity, and in the doses to other OARs were not significant. The CONKISS method balances the load among the OARs and significantly reduces the dose to the kidneys, without any significant change in the conformity and homogeneity. Using 3D-CRT the CONKISS method can be a smart alternative to IMRT to enhance the possibility of dose escalation.

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

International Nuclear Information System (INIS)

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

Comparing morbidity and cancer control after 3D-conformal (70/74 Gy) and intensity modulated radiotherapy (78/82 Gy) for prostate cancer

International Nuclear Information System (INIS)

Dolezel, Martin; Odrazka, Karel; Zouhar, Milan; Jansa, Jan; Paluska, Petr; Vaculikova, Miloslava; Sefrova, Jana; Kohlova, Tereza; Vanasek, Jaroslav; Kovarik, Josef

2015-01-01

The purpose of this work was to compare toxicity and cancer control between patients with prostate cancer treated using three-dimensional conformal radiotherapy (3D-CRT) and those treated using intensity-modulated radiation therapy (IMRT). A total of 553 patients with prostate cancer were treated with 3D-CRT 70-74 Gy (3D-CRT 70, 3D-CRT 74) or IMRT 78-82 Gy (IMRT 78, IMRT/SIB 82). Late toxicity was scored according to FC-RTOG/LENT criteria. Biochemical failure was defined using the Phoenix and ASTRO definitions. The 5-year risk of grade 2-4 genitourinary toxicity was 26.3 % (3D-CRT 70), 27.2 % (3D-CRT 74), 17.3 % (IMRT 78), and 25.1 % (IMRT/SIB 82) without statistical differences. The 5-year risk of grade 2-4 gastrointestinal toxicity was 19.4 % (3D-CRT 70), 42.1 % (3D-CRT 74), 20.5 % (IMRT 78), and 26.6 % (IMRT/SIB 82). The differences between 3D-CRT 74 and 3D-CRT 70 and between 3D-CRT 74 and IMRT 78 were statistically significant (log rank p = 0.03). The 5-year Phoenix PSA relapse-free survival (PSA-RFS) in low-risk, intermediate-risk, and high-risk patients treated using 3D-CRT were 89.4, 65.5, and 57.8 %, respectively. Patients treated with IMRT achieved the following results: 90.9, 89.4, and 83.9 %. Clinical relapse-free survival (C-RFS) in patients treated using 3D-CRT vs. IMRT for the aforementioned groups were 94.7 vs. 100 %, 86.8 vs. 98.6 %, and 84.4 vs. 94.5 %. Disease-free survival (DFS) for patients treated using 3D-CRT were 83.1, 70.9, and 71.5 %. The IMRT group reached 95.8, 89.1, and 87.6 %. The PSA-RFS for intermediate- and high-risk patients were statistically significant, while C-RFS and DFS were marginally better. Dose escalation with IMRT was associated with improved cancer control in intermediate- and high-risk patients in comparison with 3D-CRT, without compromising toxicity. (orig.) [de

External validation of three dimensional conformal radiotherapy based NTCP models for patient-rated xerostomia and sticky saliva among patients treated with intensity modulated radiotherapy

International Nuclear Information System (INIS)

Beetz, Ivo; Schilstra, Cornelis; Luijk, Peter van; Christianen, Miranda E.M.C.; Doornaert, Patricia; Bijl, Henk P.; Chouvalova, Olga; Heuvel, Edwin R. van den; Steenbakkers, Roel J.H.M.; Langendijk, Johannes A.

2012-01-01

Purpose: The purpose of this study was to investigate the ability of predictive models for patient-rated xerostomia (XER 6M ) and sticky saliva (STIC 6M ) at 6 months after completion of primary (chemo)radiation developed in head and neck cancer patients treated with 3D-conformal radiotherapy (3D-CRT) to predict outcome in patients treated with intensity modulated radiotherapy (IMRT). Methods and materials: Recently, we published the results of a prospective study on predictive models for patient-rated xerostomia and sticky saliva in head and neck cancer patients treated with 3D-CRT (3D-CRT based NTCP models). The 3D-CRT based model for XER 6M consisted of three factors, including the mean parotid dose, age, and baseline xerostomia (none versus a bit). The 3D-CRT based model for STIC 6M consisted of the mean submandibular dose, age, the mean sublingual dose, and baseline sticky saliva (none versus a bit). In the current study, a population consisting of 162 patients treated with IMRT was used to test the external validity of these 3D-CRT based models. External validity was described by the explained variation (R 2 Nagelkerke) and the Brier score. The discriminative abilities of the models were calculated using the area under the receiver operating curve (AUC) and calibration (i.e. the agreement between predicted and observed outcome) was assessed with the Hosmer–Lemeshow “goodness-of-fit” test. Results: Overall model performance of the 3D-CRT based predictive models for XER 6M and STIC 6M was significantly worse in terms of the Brier score and R 2 Nagelkerke among patients treated with IMRT. Moreover the AUC for both 3D-CRT based models in the IMRT treated patients were markedly lower. The Hosmer–Lemeshow test showed a significant disagreement for both models between predicted risk and observed outcome. Conclusion: 3D-CRT based models for patient-rated xerostomia and sticky saliva among head and neck cancer patients treated with primary radiotherapy or

Preliminary results of three-dimensional conformal radiotherapy for non-small cell lung cancer

International Nuclear Information System (INIS)

Wang Yingjie; Wang Luhua; Wang Xin; Feng Qinfu; Zhang Hongxing; Xiao Zefen; Yin Weibo

2005-01-01

Objective: To evaluate the therapeutic effects and complications of three-dimensional conformal radiotherapy (3DCRT) for non-small cell lung cancer (NSCLC). Methods: Between March 1999 and September 2003, 91 NSCLC patients treated with 3DCRT were reviewed at the Cancer Hospital, Chinese Academy of Medical Sciences. This patient cohort consisted of 73 men and 18 women. The median age was 66 years. Radio-therapy was delivered at 2 Gy fraction, 5 fractions per week. The median total dose was 60 Gy. Results: With a median follow-up time of 17 months, the response rate after 3DCRT was 57.1%, with complete remission 11.0% (10/91) and partial remission 46.2%(42/91). The median survival time (MST) was 16 months, with 1- and 2- year overall survivals (OS) of 67.0% and 32.6%, 1- and 2-year local progression free survivals (LPFS) of 82.6% and 53.0%, respectively. The independent adverse prognostic factors by univariate analysis and multivariate analysis was weight loss ≥5%. Grade 2 acute radiation pneumonitis was observed in 2 patients and grade 3 in 4 patients. Late lung injury developed in 1 patient with grade 2, 1 patient with grade 3, respectively. Acute radiation esophagitis was observed in 8 patients with grade 2. Acute grade 2 hematologic toxicity developed in 5 patients. Conclusions: 3DCRT was feasible in the treatment of NSCLC with good immediate tumor response and acceptable normal tissue complication. The total dose may potentially be increased. (authors)

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

A dosimetric comparison of 3D conformal vs intensity modulated vs volumetric arc radiation therapy for muscle invasive bladder cancer

International Nuclear Information System (INIS)

Foroudi, Farshad; Kron, Tomas; Wilson, Lesley; Bressel, Mathias; Haworth, Annette; Hornby, Colin; Pham, Daniel; Cramb, Jim; Gill, Suki; Tai, Keen Hun

2012-01-01

To compare 3 Dimensional Conformal radiotherapy (3D-CRT) with Intensity Modulated Radiotherapy (IMRT) with Volumetric-Modulated Arc Therapy (VMAT) for bladder cancer. Radiotherapy plans for 15 patients with T2-T4N0M0 bladder cancer were prospectively developed for 3-DCRT, IMRT and VMAT using Varian Eclipse planning system. The same radiation therapist carried out all planning and the same clinical dosimetric constraints were used. 10 of the patients with well localised tumours had a simultaneous infield boost (SIB) of the primary tumour planned for both IMRT and VMAT. Tumour control probabilities and normal tissue complication probabilities were calculated. Mean planning time for 3D-CRT, IMRT and VMAT was 30.0, 49.3, and 141.0 minutes respectively. The mean PTV conformity (CI) index for 3D-CRT was 1.32, for IMRT 1.05, and for VMAT 1.05. The PTV Homogeneity (HI) index was 0.080 for 3D-CRT, 0.073 for IMRT and 0.086 for VMAT. Tumour control and normal tissue complication probabilities were similar for 3D-CRT, IMRT and VMAT. The mean monitor units were 267 (range 250–293) for 3D-CRT; 824 (range 641–1083) for IMRT; and 403 (range 333–489) for VMAT (P < 0.05). Average treatment delivery time were 2:25min (range 2:01–3:09) for 3D-CRT; 4:39 (range 3:41–6:40) for IMRT; and 1:14 (range 1:13–1:14) for VMAT. In selected patients, the SIB did not result in a higher dose to small bowel or rectum. VMAT is associated with similar dosimetric advantages as IMRT over 3D-CRT for muscle invasive bladder cancer. VMAT is associated with faster delivery times and less number of mean monitor units than IMRT. SIB is feasible in selected patients with localized tumours

3DCRT for posterior fossa: Sparing of surrounding organs at risk ...

African Journals Online (AJOL)

Introduction: Radiotherapy of the posterior fossa is routinely delivered using 3DCRT parallel-opposed lateral fields. However high incidence of sensorineural hearing loss, hypothalamic– pituitary dysfunction, thyroid and gonadal dysfunction during radiotherapy makes the need for treatment plan which provides adequate ...

Dosimetric comparison of 3DCRT versus IMRT in whole breast irradiation of early stage breast cancer

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Mudasir Ashraf

2014-08-01

Full Text Available Purpose: The counseling regarding the treatment option is an important objective in the management of early stages breast cancer. In this study, we attempt to compare and analyze the dosimetric aspects of 3DRT over IMRT in the whole breast radiotherapy.Methods and Materials:  Both right and left sided computed tomography simulations of 14 women with early stage breast cancer were used for our retrospective study to compare the 3DCRT and IMRT. The dose prescribed was 50 Gy in 25 fractions to the whole breast PTV. The PTV was defined by adding unequal margins to the directional safety margin status of each lumpectomy cavity (i.e., medial, lateral, superior, inferior and deep margins measured from the tumor front after the examination of the surgical specimen: 2, 1.5, and 1 cm for resection margins < 1 cm, 1-2 cm, and > 2cm, respectively. And than modified so that it was no longer closer than 3mm to the skin surface and was no deep than the lung –chest interface. The prescribed dose delivered in 5 fractions per week schedule. Treatment plans were compared for target minimum dose, maximum dose, mean dose, conformity index, heterogeneity index and doses to organs at risk were compared and analysed.Results: The target coverage was achieved with 90% prescription to the 95% of the PTV. Conformity to the PTV was significantly higher with 3DCRT technique than IMRT. 3DCRT technique seems better in sparing critical organs parameters like lung V20 and Mean, heart, V25, Maximum, both lungs V20, Mean and Dose to the Normal Healthy tissue.Conclusion: We conclude from our study that treatment technique selection for whole Breast irradiation is an important factor in sparing the adjacent normal structures and in determining the associated risk. 3DCRT produces better conformity and heterogeneity indices of the target volume, also reduces dose to OARs the 3DCRT reduces the risk of radiation induced heart diseases

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

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

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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.

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.

Integral Dose and Radiation-Induced Secondary Malignancies: Comparison between Stereotactic Body Radiation Therapy and Three-Dimensional Conformal Radiotherapy

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Stefano G. Masciullo

2012-11-01

Full Text Available The aim of the present paper is to compare the integral dose received by non-tumor tissue (NTID in stereotactic body radiation therapy (SBRT with modified LINAC with that received by three-dimensional conformal radiotherapy (3D-CRT, estimating possible correlations between NTID and radiation-induced secondary malignancy risk. Eight patients with intrathoracic lesions were treated with SBRT, 23 Gy × 1 fraction. All patients were then replanned for 3D-CRT, maintaining the same target coverage and applying a dose scheme of 2 Gy × 32 fractions. The dose equivalence between the different treatment modalities was achieved assuming α/β = 10Gy for tumor tissue and imposing the same biological effective dose (BED on the target (BED = 76Gy10. Total NTIDs for both techniques was calculated considering α/β = 3Gy for healthy tissue. Excess absolute cancer risk (EAR was calculated for various organs using a mechanistic model that includes fractionation effects. A paired two-tailed Student t-test was performed to determine statistically significant differences between the data (p ≤ 0.05. Our study indicates that despite the fact that for all patients integral dose is higher for SBRT treatments than 3D-CRT (p = 0.002, secondary cancer risk associated to SBRT patients is significantly smaller than that calculated for 3D-CRT (p = 0.001. This suggests that integral dose is not a good estimator for quantifying cancer induction. Indeed, for the model and parameters used, hypofractionated radiotherapy has the potential for secondary cancer reduction. The development of reliable secondary cancer risk models seems to be a key issue in fractionated radiotherapy. Further assessments of integral doses received with 3D-CRT and other special techniques are also strongly encouraged.

Heart dose reduction in breast cancer treatment with simultaneous integrated boost. Comparison of treatment planning and dosimetry for a novel hybrid technique and 3D-CRT

International Nuclear Information System (INIS)

Joest, Vincent; Kretschmer, Matthias; Sabatino, Marcello; Wuerschmidt, Florian; Dahle, Joerg; Lorenzen, Joern; Ueberle, Friedrich

2015-01-01

The present study compares in silico treatment plans of clinically established three-dimensional conformal radiotherapy (3D-CRT) with a hybrid technique consisting of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) during normally fractionated radiation of mammary carcinomas with simultaneous integrated boost on the basis of dose-volume histogram (DVH) parameters. Radiation treatment planning was performed with a hybrid and a 3D-CRT treatment plan for 20 patients. Hybrid plans were implemented with two tangential IMRT fields and a VMAT field in the angular range of the tangents. Verification of the plan was performed with a manufacturer-independent measurement system consisting of a detector array and rotation unit. The mean values of the heart dose for the entire patient collective were 3.6 ± 2.5 Gy for 3D-CRT and 2.9 ± 2.1 Gy for the hybrid technique (p < 0.01). For the left side (n = 10), the mean values for the left anterior descending artery were 21.8 ± 7.4 Gy for 3D-CRT and 17.6 ± 7.4 Gy for the hybrid technique (p < 0.01). The mean values of the ipsilateral lung were 11.9 ± 1.6 Gy for 3D-CRT and 10.5 ± 1.3 Gy for the hybrid technique (p < 0.01). Calculated dose distributions in the hybrid arm were in good accordance with measured dose (on average 95.6 ± 0.5 % for γ < 1 and 3 %/3 mm). The difference of the mean treatment time per fraction was 7 s in favor of 3D-CRT. Compared with the established 3D-CRT technique, the hybrid technique allows for a decrease in dose, particularly of the mean heart and lung dose with comparable target volume acquisition and without disadvantageous low-dose load of contralateral structures. Uncomplicated implementation of the hybrid technique was demonstrated in this context. The hybrid technique combines the advantages of tangential IMRT with the superior sparing of organs at risk by VMAT. (orig.) [de

Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer

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Poli, Ana Paula Diniz Fortuna, E-mail: anapaulafortuna@yahoo.com.br [Universidade Estadual de Campinas (CAISM/UNICAMP), Campinas, SP (Brazil). Centro de Atencao Integrada a Saude da Mulher. Divisao de Radioterapia; Dias, Rodrigo Souza; Giordani, Adelmo Jose; Segreto, Helena Regina Comodo; Segreto, Roberto Araujo [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Divisao de Radioterapia

2016-01-15

Objective: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Materials and Methods: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. Results: The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation (p = 0.037). A baseline rectal volume superior to 70 cm{sup 3} had a significant influence on the prostate motion in the anteroposterior direction (p = 0.045). Conclusion: The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm{sup 3}. Therefore, the treatment of patients with a rectal volume > 70 cm{sup 3} should be re-planned with appropriate rectal preparation. Keywords: Rectal volume; Prostate cancer; Three-dimensional conformal radiotherapy. (author)

Conformal radiotherapy for locally advanced juvenile nasopharyngeal angio-fibroma

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Supriya Mallick

2015-01-01

Full Text Available Purpose: To assess the efficacy of radiation in the treatment of juvenile nasopharyngeal angiofibroma (JNA. Materials and Methods: Data were retrieved for JNA treated with radiotherapy from 1987-2012. The demographics, treatment and outcome data were recorded in predesigned proforma. Results: Data of 32 patients were retrieved. Median age was 17 years (range: 12-33 years. All patients received radiation because of refractory, residual or unresectable locally advanced disease. All patients were planned with a three-dimensional conformal technique (3DCRT. The median radiation dose was 30 Gray (range: 30-45 Gray. Median follow-up was 129 months (range: 1-276 months. At the last follow-up, 13 patients were found to have a radiological complete response. Two patients progressed 38 and 43 months after completion of treatment and opted for alternative treatment. One patient developed squamous cell carcinoma of the nasal ale 15 years after radiation. Conclusion: Conformal radiotherapy shows promise as an alternative treatment approach for locally advanced JNA and confers long-term disease control with minimal toxicity.

Experience in the radiotherapy department of Hospital Hermanos Ameijeiras in the use of 3DCRT 2drt and

International Nuclear Information System (INIS)

Sola Rodriguez, Yeline; Rodriguez Zayas, Michael; Perez Guevara, Adrian

2009-01-01

The introduction of TPS Precise Plan and the installation of an Elekta linear accelerator Entailed Precise Radiotherapy Service HHA 2DRT the evolution of a 3DCRT, the latter being a term used to describe the design and delivery planning radiation treatments based on 3D images, with fields individually shaped to the target volume and improved procedures evaluation of plans. Because of this it is necessary to estimate uncertainty in the delivered dose, which is evaluated in the 2D process 3DCRT, with emphasis on obtaining anatomical information (contour-meter vs TAC) design fields (open field vs MLC), dosimetric calculations, evaluation treatment plan and verification of isocenter. In this work took only internal processes in the treatment, such as location of the target volume and organs at risk, correction for inhomogeneities, etc. We excluded the uncertainties common to both modalities, such as: camera calibration, repeatability errors, among others. It took 40 cases treated: 20 with technical and 20 technical 2DRT 3DCRT for estimate the uncertainty of the delivered dose given each factor separately, say those involved in the planning process and supply of the treatment. This study implements a methodology which maintains or always reported decreasing uncertainties will lead to an increase quality of care. (author)

The evolution of rectal and urinary toxicity and immune response in prostate cancer patients treated with two three-dimensional conformal radiotherapy techniques

Czech Academy of Sciences Publication Activity Database

Vránová, J.; Vinakurau, S.; Richter, J.; Starec, M.; Fišerová, Anna; Rosina, J.

2011-01-01

Roč. 2, č. 6 (2011), s. 1-13 ISSN 1748-717X R&D Projects: GA AV ČR IAA500200620 Institutional research plan: CEZ:AV0Z50200510 Keywords : 3-dimensional conformal radiotherapy (3DCRT) * gastrointestinal and genitourinary toxicity * prostate cancer Subject RIV: EC - Immunology Impact factor: 2.321, year: 2011

A decision model to estimate the cost-effectiveness of intensity modulated radiation therapy (IMRT) compared to three dimensional conformal radiation therapy (3DCRT) in patients receiving radiotherapy to the prostate bed

International Nuclear Information System (INIS)

Carter, Hannah E.; Martin, Andrew; Schofield, Deborah; Duchesne, Gillian; Haworth, Annette; Hornby, Colin; Sidhom, Mark; Jackson, Michael

2014-01-01

Background: Intensity modulated radiation therapy (IMRT) is a radiation therapy technology that facilitates the delivery of an improved dose distribution with less dose to surrounding critical structures. This study estimates the longer term effectiveness and cost-effectiveness of IMRT in patients post radical prostatectomy. Methods: A Markov decision model was developed to calculate the incremental quality adjusted life years (QALYs) and costs of IMRT compared with three dimensional conformal radiation therapy (3DCRT). Costs were estimated from the perspective of the Australian health care system. Results: IMRT was both more effective and less costly than 3DCRT over 20 years, with an additional 20 QALYs gained and over $1.1 million saved per 1000 patients treated. This result was robust to plausible levels of uncertainty. Conclusions: IMRT was estimated to have a modest long term advantage over 3DCRT in terms of both improved effectiveness and reduced cost. This result was reliant on clinical judgement and interpretation of the existing literature, but provides quantitative guidance on the cost effectiveness of IMRT whilst long term trial evidence is awaited

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.

IMRT and 3D conformal radiotherapy with or without elective nodal irradiation in locally advanced NSCLC. A direct comparison of PET-based treatment planning

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Fleckenstein, Jochen; Kremp, Katharina; Kremp, Stephanie; Palm, Jan; Ruebe, Christian [Saarland University Medical School, Department of Radiotherapy and Radiation Oncology, Homburg/Saar (Germany)

2016-02-15

The potential of intensity-modulated radiation therapy (IMRT) as opposed to three-dimensional conformal radiotherapy (3D-CRT) is analyzed for two different concepts of fluorodeoxyglucose positron emission tomography (FDG PET)-based target volume delineation in locally advanced non-small cell lung cancer (LA-NSCLC): involved-field radiotherapy (IF-RT) vs. elective nodal irradiation (ENI). Treatment planning was performed for 41 patients with LA-NSCLC, using four different planning approaches (3D-CRT-IF, 3D-CRT-ENI, IMRT-IF, IMRT-ENI). ENI included a boost irradiation after 50 Gy. For each plan, maximum dose escalation was calculated based on prespecified normal tissue constraints. The maximum prescription dose (PD), tumor control probability (TCP), conformal indices (CI), and normal tissue complication probabilities (NTCP) were analyzed. IMRT resulted in statistically significant higher prescription doses for both target volume concepts as compared with 3D-CRT (ENI: 68.4 vs. 60.9 Gy, p < 0.001; IF: 74.3 vs. 70.1 Gy, p < 0.03). With IMRT-IF, a PD of at least 66 Gy was achieved for 95 % of all plans. For IF as compared with ENI, there was a considerable theoretical increase in TCP (IMRT: 27.3 vs. 17.7 %, p < 0.00001; 3D-CRT: 20.2 vs. 9.9 %, p < 0.00001). The esophageal NTCP showed a particularly good sparing with IMRT vs. 3D-CRT (ENI: 12.3 vs. 30.9 % p < 0.0001; IF: 15.9 vs. 24.1 %; p < 0.001). The IMRT technique and IF target volume delineation allow a significant dose escalation and an increase in TCP. IMRT results in an improved sparing of OARs as compared with 3D-CRT at equivalent dose levels. (orig.) [German] Das Potenzial der intensitaetsmodulierten Strahlentherapie (IMRT) soll im Rahmen der FDG-PET basierten Bestrahlungsplanung des lokal fortgeschrittenen nichtkleinzelligen Bronchialkarzinoms (LA-NSCLC) fuer 2 Zielvolumenansaetze (Involved-Field-Bestrahlung, IF) sowie elektive Nodalbestrahlung (ENI) geprueft und mit der 3-D-konformalen Strahlentherapie (3-D-CRT

Three dimensional conformal radiation therapy (3d-crt) in prostate carcinoma: for whom and how?; La radiotherapie conformationnelle dans le cancer de la prostate: pour qui et comment?

Energy Technology Data Exchange (ETDEWEB)

Bey, P.; Beckendorf, V.; Aletti, P.; Marchesi, V. [Centre Alexis-Vautrin, Dept. de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France)

2002-05-01

External radiotherapy is one of the modalities use o cure localized prostate carcinoma. Most of localized prostate carcinomas, specially those of the intermediate prognostic group, may benefit from escalated dose above 70 Gy at least as regard biochemical and clinical relapse free survival. 3D-CRT allows a reduction of the dose received by organs at risk and an increase of prostate dose over 70 Gy. It is on the way to become a standard. Intensity modulated radiation therapy increases dose homogeneity and reduces rectal dose. These methods necessitate rigorous procedures in reproducibility, delineation of volumes, dosimetry, daily treatment. They need also technological and human means. It is clear that localized prostate cancer is a good example for evaluation of these new radiotherapy modalities. (author)

A custom made phantom for dosimetric audit and quality assurance of three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Radaideh, K.M.; Matalqah, L.M.; Matalqah, L.M.; Tajuddin, A.A.; Luen, F.W.L.; Bauk, S.; Abdel Munem, E.M.E.

2012-01-01

The ultimate check of the actual dose delivered to a patient in radiotherapy can be achieved by using dosimetric measurements. The aims of this study were to develop and evaluate a custom handmade head and neck phantom for evaluation of Three-Dimensional Conformal Radiation Therapy (3D-CRT) dose planning and delivery. A phantom of head and neck region of a medium built male patient with nasopharyngeal cancer was constructed from Perspex material. Primary and secondary Planning Target Volume (PTV) and twelve Organs at Risk (OAR) were delineated using Treatment Planning System (TPS) guided by computed tomography printout transverse images. One hundred and seven (107) holes distributed among the organs were loaded with Rod-shaped Thermoluminescent dosimeters (LiF:Mg, Ti TLDs) after common and individual calibration. Head and neck phantom was imaged, planned and irradiated conformally (3D-CRT) by linear accelerator (LINAC Siemens Artiste). The planned predicted doses by TPS at PTV and OAR regions were obtained and compared with the TLD measured doses using the phantom. Repeated TLD measurements were reproducible with a percent standard deviation of < 3.5 %. Moreover, the average of dose discrepancies between TLDs reading and TPS predicted doses were found to be < 5.3 %. The phantom's preliminary results have proved to be a valuable tool for 3D-CRT treatment dose verification. (author)

Procedure for image acquisition and dosimetric planning for prostate cancer with 3D-CRT in the MIRS 3.0

International Nuclear Information System (INIS)

Perez Velasquez, Reytel; Alvarez Zaldivar, Junior; Gonzalez Lopez, Nadia

2009-01-01

For over 30 years in the department of Radiotherapy of the Lenin Hospital has been doing conventional radiotherapy. In this paper we describe the dose planning procedure for patients with prostate cancer with 3D-CRT in the MIRS RTPS 3.0. The work ranges from imaging in the TAC including quality control of this, the definition of bodies radio therapists medical risk to the data to be transferred to processing machine. With this procedure we have established guidelines for planning 3D-CRT treatments for other locations. (author)

Auto-optimisation for three-dimensional conformal radiotherapy of nasopharyngeal carcinoma

Energy Technology Data Exchange (ETDEWEB)

Wu, V.W.C. E-mail: orvinwu@polyu.edu.hk; Kwong, D.W.L.; Sham, J.S.T.; Mui, A.W.L

2003-08-01

Purpose: The purpose of this study was to evaluate the application of auto-optimisation in the treatment planning of three-dimensional conformal radiotherapy (3DCRT) of nasopharyngeal carcinoma (NPC). Methods: Twenty-nine NPC patients were planned by both forward planning and auto-optimisation methods. The forward plans, which consisted of three coplanar facial fields, were produced according to the routine planning criteria. The auto-optimised plans, which consisted of 5-15 (median 9) fields, were generated by the planning system after prescribing the dose requirements and the importance weightings of the planning target volume and organs at risk. Plans produced by the two planning methods were compared by the dose volume histogram, tumour control probability (TCP), conformity index and normal tissue complication probability (NTCP). Results: The auto-optimised plans reduced the average planner's time by over 35 min. It demonstrated better TCP and conformity index than the forward plans (P=0.03 and 0.04, respectively). Besides, the parotid gland and temporo-mandibular (TM) joint were better spared with the mean dose reduction of 31.8 and 17.7%, respectively. The slight trade off was the mild dose increase in spinal cord and brain stem with their maximum doses remaining within the tolerance limits. Conclusions: The findings demonstrated the potentials of auto-optimisation for improving target dose and parotid sparing in the 3DCRT of NPC with saving of the planner's time.

Auto-optimisation for three-dimensional conformal radiotherapy of nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Wu, V.W.C.; Kwong, D.W.L.; Sham, J.S.T.; Mui, A.W.L.

2003-01-01

Purpose: The purpose of this study was to evaluate the application of auto-optimisation in the treatment planning of three-dimensional conformal radiotherapy (3DCRT) of nasopharyngeal carcinoma (NPC). Methods: Twenty-nine NPC patients were planned by both forward planning and auto-optimisation methods. The forward plans, which consisted of three coplanar facial fields, were produced according to the routine planning criteria. The auto-optimised plans, which consisted of 5-15 (median 9) fields, were generated by the planning system after prescribing the dose requirements and the importance weightings of the planning target volume and organs at risk. Plans produced by the two planning methods were compared by the dose volume histogram, tumour control probability (TCP), conformity index and normal tissue complication probability (NTCP). Results: The auto-optimised plans reduced the average planner's time by over 35 min. It demonstrated better TCP and conformity index than the forward plans (P=0.03 and 0.04, respectively). Besides, the parotid gland and temporo-mandibular (TM) joint were better spared with the mean dose reduction of 31.8 and 17.7%, respectively. The slight trade off was the mild dose increase in spinal cord and brain stem with their maximum doses remaining within the tolerance limits. Conclusions: The findings demonstrated the potentials of auto-optimisation for improving target dose and parotid sparing in the 3DCRT of NPC with saving of the planner's time

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

Energy Technology Data Exchange (ETDEWEB)

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

Details of recurrence sites after elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT) combined with chemotherapy for thoracic esophageal squamous cell carcinoma--a retrospective analysis.

Science.gov (United States)

Yamashita, Hideomi; Okuma, Kae; Wakui, Reiko; Kobayashi-Shibata, Shino; Ohtomo, Kuni; Nakagawa, Keiichi

2011-02-01

To describe patterns of recurrence of elective nodal irradiation (ENI) in definitive chemoradiotherapy (CRT) for thoracic esophageal squamous cell carcinoma (SqCC) using 3D-conformal radiotherapy. One hundred and twenty-six consecutive patients with stages I-IVB thoracic esophageal SqCC newly diagnosed between June 2000 and July 2009 and treated with 3D-CRT in our institution were recruited from our database. Definitive CRT consisted of two cycles of nedaplatin/5FU repeated every 4 weeks, with concurrent radiation therapy of 50-50.4 Gy in 25-28 fractions. Until completion, radiotherapy was delivered to the N1 and M1a lymph nodes as ENI in addition to gross tumor volume. All 126 patients were included in this analysis, and their tumors were staged as follows: T1/T2/T3/T4, 28/18/54/26; N0/N1, 50/76; M0/M1a/M1b, 91/5/30. The mean follow-up period for the 63 surviving patients was 28.3 (±22.8) months. Eighty-seven patients (69%) achieved complete response (CR) without any residual tumor at least once after completion of CRT. After achieving CR, each of 40 patients experienced failures (local=20 and distant=20) and no patient experienced elective nodal failure without having any other site of recurrence. The upper thoracic esophageal carcinoma showed significantly more (34%) relapses at the local site than the middle (9%) or lower thoracic (11%) carcinomas. The 2-year and 3-year overall survival was 56% and 43%, respectively. The 1-year, 2-year and 3-year disease-free survival was 46%, 38% and 33%, respectively. In CRT for esophageal SqCC, ENI was effective for preventing regional nodal failure. The upper thoracic esophageal carcinomas had significantly more local recurrences than the middle or lower thoracic sites. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Prognosis comparison of three-dimensional conformal radiotherapy/intensity modulated radiation therapy for esophageal carcinoma with local regional lymph node metastasis

International Nuclear Information System (INIS)

Wang Yuxiang; Wang Jun; Wang Yi; Tian Dandan; Yang Jie; Zhu Shuchai

2011-01-01

Objective: To explore the prognosis and related factor of esophageal carcinoma with locoregional lymph node metastasis (N 1 ) treated with three-dimensional conformal radiotherapy (3DCRT) or intensity modulated radiation therapy (IMRT). Methods: From January 2001 to December 2008, 60 patients of esophageal carcinoma with local regional lymph node metastasis were treated with 3DCRT and 52 with IMRT. For all patients,dose of tumor was 56 - 70 Gy/28 - 35 fraction/5.6 - 7.0 weeks. Among them, 58 cases was treated with chemotherapy including cisplatin and 5-fluorouracil; 40 with concurrent chemoradiotherapy and 18 with sequential radiotherapy and chemotherapy. Results: After radiotherapy,the total efficiency rate was 98.2%, 96.7% in 3DCRT and 100% in IMRT (χ 2 =1.77, P =0.184). The follow-up rate was 99.1%. The number of patients completed follow-up were 68 and 53, respectively at 2-year and 3-year. The 1 and 3-year overall survival rates were 62.5%, 23.7%, respectively; the median survival time was 17 months. The 1 and 3-year survival rates and median were 52%, 19% and 12.4 months in 3DCRT and 75%, 40% and 17 months in IMRT, respectively (χ 2 =4.74, P =0.030). The 1 and 3-year free-recurrence survival rates were 64%, 45% in 3DCRT and 72%, 59% in IMRT (χ 2 =2.27, P =0.132), respectively. With univariate analysis, for female, ages ≤ 65, tumor located in cervical and upper-thoracic, >5 cm lesion length in barium esophagogram, ≤4 cm the largest diameter of lesion in CT scanning image, T 4 stage, or semiliquid or liquid diet before radiotherapy, survival rate were higher in IMRT than in 3DCRT group (χ 2 =4.63, 5.56, 7.19, 5.08, 4.43, 4.48, 8.25; P=0.031, 0.018, 0.007, 0.025, 0.035, 0.034, 0.004, respectively); but for male, ages > 65, tumor located in middle and lower-thoracic, ≤5 cm lesion length in barium esophagogram, >4 cm the largest diameter of lesion in CT scanning image, T 1-3 stage, or normal diet before radiotherapy, chemotherapy and dose of radiotherapy

FXG dosimeter response for three-dimensional conformal radiotherapy using different evaluation techniques

Energy Technology Data Exchange (ETDEWEB)

Cavinato, Christianne C.; Campos, Leticia L., E-mail: ccavinato@ipen.b, E-mail: lcrodri@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Souza, Benedito H.; Carrete Junior, Henrique; Daros, Kellen A.C.; Medeiros, Regina B., E-mail: bhsouza@unifesp.b, E-mail: daros.kellen@unifesp.b, E-mail: rbitel-li.ddi@epm.b [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Dept. de Diagnostico por Imagem; Giordani, Adelmo J. [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Servico de Radioterapia

2011-07-01

This work aims to compare the dose-response of the Fricke xylenol gel (FXG) dosimeter developed at IPEN using 270 Bloom gelatin from porcine skin made in Brazil evaluated using the magnetic resonance imaging (MRI) technique with the dosimetric response evaluated using the optical absorption (OA) spectrophotometry technique, in order to verify the possibility of quality assurance (QA) and reproducibility of FXG dosimeter to be carried out routinely using the OA technique for three-dimensional conformal radiotherapy (3DCRT) application using a 6 MV photons linear accelerator. The response in function of the absorbed dose of FXG dosimeter developed at IPEN presents linear behavior in clinical interest dose range when irradiated with Co-60 gamma radiation and 6 MV photons and evaluated using the MRI and OA techniques. The results indicate that the optical technique can be used for QA of FXG dosemeter when used in the possible application in QA of 3DCRT. (author)

FXG dosimeter response for three-dimensional conformal radiotherapy using different evaluation techniques

International Nuclear Information System (INIS)

Cavinato, Christianne C.; Campos, Leticia L.; Souza, Benedito H.; Carrete Junior, Henrique; Daros, Kellen A.C.; Medeiros, Regina B.; Giordani, Adelmo J.

2011-01-01

This work aims to compare the dose-response of the Fricke xylenol gel (FXG) dosimeter developed at IPEN using 270 Bloom gelatin from porcine skin made in Brazil evaluated using the magnetic resonance imaging (MRI) technique with the dosimetric response evaluated using the optical absorption (OA) spectrophotometry technique, in order to verify the possibility of quality assurance (QA) and reproducibility of FXG dosimeter to be carried out routinely using the OA technique for three-dimensional conformal radiotherapy (3DCRT) application using a 6 MV photons linear accelerator. The response in function of the absorbed dose of FXG dosimeter developed at IPEN presents linear behavior in clinical interest dose range when irradiated with Co-60 gamma radiation and 6 MV photons and evaluated using the MRI and OA techniques. The results indicate that the optical technique can be used for QA of FXG dosemeter when used in the possible application in QA of 3DCRT. (author)

SU-E-T-63: Carotid Sparing Tomohelical Three Dimensional Conformal Radiotherapy for T1N0 Glottic Cancer

Energy Technology Data Exchange (ETDEWEB)

Hong, C; Ju, S; Ahn, Y; Oh, D; Noh, J; Chung, K; Kim, J; Han, Y; Choi, D [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2014-06-01

Purpose: We investigated the dosimetric benefit and treatment efficiency of carotid-sparing TomoHelical (TH) three-dimensional conformal radiotherapy (3DCRT) for early glottic cancer. Methods: Computed tomography (CT) simulation was performed for 10 patients with early-stage (T1N0M0) glottic squamous cell carcinoma. The clinical target volume, planning target volume (PTV), carotid artery (CA), and spinal cord (SP) were delineated for each CT data set. Two-field 3DCRT (2F-3DCRT), three-field intensity-modulated radiation therapy (IMRT) (3F-IMRT), TomoHelical-IMRT (TH-IMRT), and TH-3DCRT plans were generated, with a total prescribed dose of 67.5 Gy in 30 fractions to the PTV for each patient. In order to evaluate plan quality, dosimetric characteristics were compared in terms of the conformity index (CI) and homogeneity index (HI) for the PTV, V35, V50, and V63 for the CAs and in terms of the maximum dose for the SP. Additionally, treatment planning and delivery times were compared to evaluate treatment efficiency. Results: The CIs for 3F-IMRT (0.650±0.05), TH-IMRT (0.643±0.03), and TH-3DCRT (0.631±0.03) were much better than that for 2F-3DCRT (0.318±0.03). The HIs for TH-IMRT (1.053±0.01) and TH-3DCRT (1.055±0.01) were slightly better than those for 2F-3DCRT (1.062±0.01) and 3F-IMRT (1.091±0.007). 2F-3DCRT showed poor CA sparing in terms of the V35, V50, and V63 compared to 3F-IMRT, TH-IMRT, and TH-3DCRT (p<0.05), whereas there was no significant dose difference between 3F-IMRT, TH-IMRT, and TH-3DCRT (p>0.05). The maximum dose to the SP with all plans was below 45 Gy. The treatment planning times for 2F-3DCRT (5.9±0.66 min) and TH-3DCRT (7.32±0.94 min) were much lower than those for 3F-IMRT (45.51±2.76 min) and TH-IMRT (35.58±4.41 min), whereas the delivery times with all plans was below 3 minutes. Conclusion: TH-3DCRT showed excellent carotid sparing capability, comparable to that with TH-IMRT, with high treatment efficiency and short planning and

Procedure for image acquisition and dose planning of prostate cancer with 3D-CRT in the MIRS 3.0

International Nuclear Information System (INIS)

Perez Velasquez, Reytel; Alvarez Zaldivar, Junior; Gonzalez Lopez, Nadia

2009-01-01

For over 30 years in the department of Radiotherapy of the Lenin Hospital has been making conventional radiotherapy. In the present work is presented the procedure for dosimetric planning of patients with prostate cancer with 3D-CRT in the MIRS RTPS 3.0. The work ranges from image acquisition in the TAC, its including quality control, the definition of organs at risk by medical radiation therapists to the data to be transferred to the treatment machine. With this procedure has been possible to establish guidelines for planning 3D-CRT treatments for other locations. (author)

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

Setup error in three-dimensional conformal radiotherapy for thoracic esophageal carcinoma

International Nuclear Information System (INIS)

Hong Jinsheng; Zhang Weijian; Chen Jinmei; Cai Chuanshu; Ke Chunlin; Chen Xiuying; Wu Bing; Guo Feibao

2009-01-01

Objective: To study the setup errors in three-dimensional conformal radiotherapy (3DCRT) for thoracic esophageal carcinoma using electronic portal imaging device(EPID) and calculate the margins from CTV to PTV. Methods: Forty-one patients with thoracic esophageal carcinoma who received 3DCRT were continuously enrolled into this study. The anterior and lateral electronic portal images (EPI) were aquired by EPID once a week. The setup errors were obtained through comparing the difference between EPI and digitally reconstructed radiographs (DRR). Then the setup margins from CTV to PTV were calculated. By using self paired design, 22 patients received definitive radiotherapy with different margins. Group A: the margins were 10 mm in all the three axes; Group B: the margins were aquired in this study. The difference were compared by Paired t-test or Wilcoxon signed-rank test. Results: The margins from CTV to PTV in x, y and z axes were 8.72 mm, 10.50 mm and 5.62 mm, respectively. Between the group A and group B, the difference of the maximum dose of the spinal cord was significant(4638.7 cGy ± 1449.6 cGy vs. 4310.2 cGy ± 1528.7 cGy; t=5.48, P=0.000), and the difference of NTCP for the spinal cord was also significant (4.82% ± 5.99% vs. 3.64% ± 4.70%; Z=-2.70, P=0.007). Conclusions: For patients with thoracic esophageal carcinoma who receive 3DCRT in author's department, the margins from CTV to PTV in x, y and z axes were 8.72 mm, 10.50 mm and 5.62 mm, respectively. The spinal cord could be better protected by using these setup margins than using 10 mm in each axis. (authors)

Evidence-based review of three-dimensional conformal radiotherapy for localized prostate cancer: An ASTRO outcomes initiative

International Nuclear Information System (INIS)

Morris, David E.; Emami, Bahman; Mauch, Peter M.; Konski, Andre A.; Tao, May L.; Ng, Andrea K.; Klein, Eric A.; Mohideen, Najeeb; Hurwitz, Mark D.; Fraas, Bendick A.; Roach, Mack; Gore, Elizabeth M.; Tepper, Joel E.

2005-01-01

Purpose: To perform a systematic review of the evidence to determine the efficacy and effectiveness of three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer; provide a clear presentation of the key clinical outcome questions related to the use of 3D-CRT in the treatment of localized prostate cancer that may be answered by a formal literature review; and provide concise information on whether 3D-CRT improves the clinical outcomes in the treatment of localized prostate cancer compared with conventional RT. Methods and Materials: We performed a systematic review of the literature through a structured process developed by the American Society for Therapeutic Radiology and Oncology's Outcomes Committee that involved the creation of a multidisciplinary task force, development of clinical outcome questions, a formal literature review and data abstraction, data review, and outside peer review. Results: Seven key clinical questions were identified. The results and task force conclusions of the literature review for each question are reported. Conclusion: The technological goals of reducing morbidity with 3D-CRT have been achieved. Randomized trials and follow-up of completed trials remain necessary to address these clinical outcomes specifically with regard to patient subsets and the use of hormonal therapy

Towards multidimensional radiotherapy (MD-CRT): biological imaging and biological conformality

International Nuclear Information System (INIS)

Ling, C. Clifton; Humm, John; Larson, Steven; Amols, Howard; Fuks, Zvi; Leibel, Steven; Koutcher, Jason A.

2000-01-01

Purpose: The goals of this study were to survey and summarize the advances in imaging that have potential applications in radiation oncology, and to explore the concept of integrating physical and biological conformality in multidimensional conformal radiotherapy (MD-CRT). Methods and Materials: The advances in three-dimensional conformal radiotherapy (3D-CRT) have greatly improved the physical conformality of treatment planning and delivery. The development of intensity-modulated radiotherapy (IMRT) has provided the 'dose painting' or 'dose sculpting' ability to further customize the delivered dose distribution. The improved capabilities of nuclear magnetic resonance imaging and spectroscopy, and of positron emission tomography, are beginning to provide physiological and functional information about the tumor and its surroundings. In addition, molecular imaging promises to reveal tumor biology at the genotype and phenotype level. These developments converge to provide significant opportunities for enhancing the success of radiotherapy. Results: The ability of IMRT to deliver nonuniform dose patterns by design brings to fore the question of how to 'dose paint' and 'dose sculpt', leading to the suggestion that 'biological' images may be of assistance. In contrast to the conventional radiological images that primarily provide anatomical information, biological images reveal metabolic, functional, physiological, genotypic, and phenotypic data. Important for radiotherapy, the new and noninvasive imaging methods may yield three-dimensional radiobiological information. Studies are urgently needed to identify genotypes and phenotypes that affect radiosensitivity, and to devise methods to image them noninvasively. Incremental to the concept of gross, clinical, and planning target volumes (GTV, CTV, and PTV), we propose the concept of 'biological target volume' (BTV) and hypothesize that BTV can be derived from biological images and that their use may incrementally improve

Prospective study on the dose distribution to the acoustic structures during postoperative 3D conformal radiotherapy for parotid tumors. Dosimetric and audiometric aspects

International Nuclear Information System (INIS)

Jereczek-Fossa, Barbara A.

2011-01-01

To analyze dose distribution in the hearing organ and to evaluate the dose effect on the hearing thresholds in patients treated with post-parotidectomy 3-dimensional conformal radiotherapy (3D-CRT). A total of 17 patients received post-parotidectomy 3D-CRT (median dose: 63 Gy). The audiometric evaluation comprised pure tone audiometry and tympanometry performed before radiotherapy (RT) and 3, 6, and 24 months after RT. The ear structures were delineated on planning computer tomography scans. Mean and maximum doses were calculated and dose-volume histograms were plotted. Before RT, the median baseline audiometric thresholds were normal. At 3 months post-RT, 3 patients were diagnosed as having middle ear underpressure and/or effusion that resolved completely by 6 months. During 2-year follow-up, none of the ears showed perceptive hearing loss at speech frequencies. The mean doses at ipsilateral external auditory canal, mastoids cells, tympanic case, Eustachian tube, semicircular canals, and cochlea were 44.8 Gy, 39.0 Gy, 30.9 Gy, 33.0 Gy, 19.6 Gy, and 19.2 Gy, respectively. The doses to the contralateral ear were negligible, except for the Eustachian tube (up to 28.2 Gy). Post-parotidectomy 3D-CRT is associated with relatively low doses to the ear and the surrounding structures. Post-RT audiometry did not show any permanent (neither conductive nor perceptive) hearing impairment. Only in 3 patients were there signs of transient unilateral dysfunction of the Eustachian tube observed during the first few months after RT. Longer follow-up and larger patient series are warranted to confirm these preliminary findings. (orig.)

Dosimetric comparison of helical tomotherapy, intensity-modulated radiation therapy, volumetric-modulated arc therapy, and 3-dimensional conformal therapy for the treatment of T1N0 glottic cancer

International Nuclear Information System (INIS)

Ekici, Kemal; Pepele, Eda K.; Yaprak, Bahaddin; Temelli, Oztun; Eraslan, Aysun F.; Kucuk, Nadir; Altınok, Ayse Y.; Sut, Pelin A.; Alpak, Ozlem D.; Colak, Cemil; Mayadagli, Alpaslan

2016-01-01

Various radiotherapy planning methods for T1N0 laryngeal cancer have been proposed to decrease normal tissue toxicity. We compare helical tomotherapy (HT), linac-based intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), and 3-D conformal radiotherapy (3D-CRT) techniques for T1N0 laryngeal cancer. Overall, 10 patients with T1N0 laryngeal cancer were selected and evaluated. Furthermore, 10 radiotherapy treatment plans have been created for all 10 patients, including HT, IMRT, VMAT, and 3D-CRT. IMRT, VMAT, and HT plans vs 3D-CRT plans consistently provided superior planning target volume (PTV) coverage. Similar target coverage was observed between the 3 IMRT modalities. Compared with 3D-CRT, IMRT, HT, and VMAT significantly reduced the mean dose to the carotid arteries. VMAT resulted in the lowest mean dose to the submandibular and thyroid glands. Compared with 3D-CRT, IMRT, HT, and VMAT significantly increased the maximum dose to the spinal cord It was observed that the 3 IMRT modalities studied showed superior target coverage with less variation between each plan in comparison with 3D-CRT. The 3D-CRT plans performed better at the D max of the spinal cord. Clinical investigation is warranted to determine if these treatment approaches would translate into a reduction in radiation therapy–induced toxicities.

Intensity modulated radiotherapy (IMRT) in bilateral retinoblastoma

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Atalar, Banu; Ozyar, Enis; Gunduz, Kaan; Gungor, Gorkem

2010-01-01

External beam radiotherapy (EBRT) for retinoblastoma has traditionally been done with conventional radiotherapy techniques which resulted high doses to the surrounding normal tissues. A 20 month-old girl with group D bilateral retinoblastoma underwent intensity modulated radiotherapy (IMRT) to both eyes after failing chemoreduction and focal therapies including cryotherapy and transpupillary thermotherapy. In this report, we discuss the use of IMRT as a method for reducing doses to adjacent normal tissues while delivering therapeutic doses to the tumour tissues compared with 3-dimensional conformal radiotherapy (3DCRT). At one year follow-up, the patient remained free of any obvious radiation complications. Image guided IMRT provides better dose distribution than 3DCRT in retinoblastoma eyes, delivering the therapeutic dose to the tumours and minimizing adjacent tissue damage

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 [University Hospital S. Chiara, Radiation Oncology, Pisa (Italy); D' Angelo, Elisa; Lohr, Frank [University Hospital, Radiation Oncology, Modena (Italy); Mazzola, Rosario [Sacro Cuore-Don Calabria Cancer Care Center, Radiation Oncology, Negrar-Verona (Italy); Merlotti, Anna; Russi, Elvio Grazioso [S. Croce e Carle Hospital, Radiation Oncology, Cuneo (Italy); Musio, Daniela [University Hospital La Sapienza, Radiation Oncology, Roma (Italy); Alterio, Daniela [European Institute of Oncology, Radiation Oncology, Advanced Radiotherapy Center, Milan (Italy); Bacigalupo, Almalina [AOU IRCCS San Martino - IST National Cancer Research Institute and University, Radiation Oncology, Genoa (Italy)

2017-11-15

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.) [German] Dysphagie ist eine der wichtigsten Nebenwirkungen bei der Behandlung von Kopf-Hals-Tumoren (HNC), da sie zu lebensbedrohlichen Komplikationen wie Aspirationspneumonien und Mangelernaehrung fuehren kann. Durch Erzeugung konkaver Dosisverteilungen und durch die Reduzierung der Dosis an schluckrelevanten Strukturen (SWOAR) kann die IMRT Schluckstoerungen moeglicherweise vermindern. Ziel dieser Studie war es, die gegenwaertige Literaturlage hinsichtlich der Schluckfunktion nach IMRT und konformaler dreidimensionaler Strahlentherapie (3DCRT) systematisch zu ueberpruefen. Studien, die die

Implementation of three dimensional conformal radiation therapy: prospects, opportunities, and challenges

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Vijayakumar, Srinivasan; Chen, George T.Y.

1995-01-01

Purpose: To briefly review scientific rationale of 3D conformal radiation therapy (3DCRT) and discuss the prospects, opportunities, and challenges in the implementation of 3DCRT. Some of these ideas were discussed during a workshop on 'Implementation of Three-Dimensional Conformal Radiation Therapy' in April 1994 at Bethesda, MD, and others have been discussed elsewhere in the literature. Methods and Materials: Local-regional control of cancer is an important component in the overall treatment strategy in any patient with cancer. It has been shown that failure to achieve local-regional control can lead to (a) an increase in chances of distant metastases, and (b) a decrease in the survival. In many disease sites, the doses delivered currently are inadequate to achieve satisfactory local tumor control rates; this is because in many sites, only limited doses of radiotherapy can be delivered due to the proximity of cancer to radiosensitive normal tissues. By conforming the radiotherapy beams to the tumor, doses to the tumors can be enhanced and doses to the normal tissues can be reduced. With the advances in 3DCRT, such conformation is possible now and is the rationale for using 3DCRT. However, a number of questions do remain that are not limited to the following: (a) What are the implications in terms of target volume definitions when implementing 3DCRT? (b) Are there some sites where research efforts can be focused to document the efficacy and cost effectiveness of 3DCRT? (c) How do we implement day-to-day 3DCRT treatment efficiently? (d) How do we transfer the technology from the university centers to the community without compromising quality? (e) What are all the quality assurance/quality improvement questions that need to be addressed and how do we ascertain quality assurance of 3DCRT? (f) Have we looked at cost-benefit ratios and quality of life (QOL) issues closely? Results: There is a need for defining multiple target volumes: gross tumor volume, clinical

Three-dimensional conformal radiotherapy in the treatment of prostate cancer in Australia and New Zealand: Report on a survey of radiotherapy centres and the proceedings of a consensus workshop

International Nuclear Information System (INIS)

Tai, K.-H.; Duchesne, G.; See, A.; Berry, M.

2004-01-01

There is an increasing use of 3-D conformal radiotherapy (3DCRT) in the radiotherapeutic management of prostate cancer. The Faculty of Radiation Oncology Genito-Urinary Group carried out a survey of Australian and New Zealand radiotherapy centres in the preparation of a consensus workshop. Of the 19 centres that were represented, there were 24 radiation oncologists, 16 radiation therapists and 12 medical physicists. The survey collected demographic information and data on the practices undertaken at those centres when delivering curative radiotherapy in the treatment of prostate cancer. There was much variation in the delivery of treatment in the areas of patient set-up, contouring of target volumes and organs of interest during computer planning, the techniques and the dose constraints used in these techniques, the use of adjuvant androgen deprivation therapy and the quality assurance processes used in monitoring effects of treatment. This variability reflects the range of data in the published literature. Emerging trends of practices were also identified. This is a first report on a multi-disciplinary approach to the development of guidelines in 3DCRT of prostate cancer. Copyright (2004) Blackwell Science Pty Ltd

Potency following high-dose three-dimensional conformal radiotherapy and the impact of prior major urologic surgical procedures in patients treated for prostate cancer

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Chinn, Daniel M.; Holland, John; Crownover, Richard L.; Roach, Mack

1995-01-01

Purpose: To assess the impact of high-dose three-dimensional conformal radiotherapy (3DCRT) on potency in patients treated for clinically localized prostate cancer and to identify factors that might predict the outcome of sexual function following treatment. Methods and Materials: One hundred twenty-four consecutive patients treated with 3DCRT for localized prostate cancer at UCSF between 1991-1993 were included in this retrospective analysis. Patient responses were obtained from a mailed questionnaire, telephone interviews, or departmental records. Median follow-up was 21 months. Results: Sixty patients reported having sexual function prior to 3DCRT, including 47 who were fully potent and 13 who were marginally potent. Of the remaining 64 patients, 45 were impotent, 7 were on hormones, 1 was status-postorchiectomy, and 11 were not evaluable. Following 3DCRT, 37 of 60 patients (62%) retained sexual function sufficient for intercourse. Of those with sexual function before irradiation, 33 of 47 (70%) of patients fully potent and 4 of 13 (31%) of patients marginally potent maintained function sufficient for intercourse (p < 0.01). Potency was retained in 6 of 15 (40%) patients with a history of a major urologic surgical procedure (MUSP) and in 31 of 45 (69%) with no history of a MUSP (p < 0.04). Transurethral resection of the prostate was the MUSP in eight of these patients, with four (50%) maintaining sexual function. Conclusions: Patients who receive definitive 3DCRT for localized prostate cancer appear to maintain potency similar to patients treated with conventional radiotherapy. However, patients who are marginally potent at presentation or who have a history of a MUSP appear to be at increased risk of impotence following 3DCRT

Dosimetry analysis on radiation-induced acute esophagitis after three-dimensional conformal radiotherapy for non-small cell lung cancer

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ZZhu Shuchai; Cui Yanli; Li Juan; Liu Zhikun; Shen Wenbin; Su Jingwei; Wang Yuxiang

2010-01-01

Objective: To analyze the related factors with radiation-induced esophagitis after threedimensional conformal radiotherapy for non-small cell lung cancer (NSCLC), in order to explore the predictors for optimizing the treatment planning of NSCLC. Methods: From Aug 2000 to Dec 2004, 104 NSCLC patients received radiotherapy and were eligible for this study, 45 cases squamous cell carcinoma, 20 cases adenocarcinoma, 33 cases carrying with cancer cells by test and 6 case with no definitive pathologic feature.46 patients were treated with three dimensional conformal radiotherapy (3DCRT), the other 58 patients conventional radiotherapy (CRT) before later-course 3DCRT. All the patients received the prescribed dose between 60-78 Gy and the median dose 66 Gy. The correlation of the variables were evaluated by Spearman relationship analysis. The morbidity of radiation-induced esophagitis was analyzed by X 2 test. The multivariate effect on radiation-induced esophagitis was statistically processed by Logistic regression model. Results: In 104 patients, the morbidity of radiation- induced esophagitis was 46.2%, including 32 cases at grade 1, 15 cases at grade 2, 1 case at grade 3. Univariate analysis showed the maximal and mean dose of esophagus, the volume of esophagus irradiated, the values of V 40 , V 45 , V 50 , V 55 , V 60 , LETT 45 , LETT 50 , LETT 55 , LETT 60 for the esophagus were correlated with radiation-induced esophagitis. Logistic regression model showed that the maximum dose received by the esophagus was the independent factor of ≥ 2 grade radiation-induced esophagitis. Conclusions: The maxmal dose of esophagus received might be the important factor of radiation-induced esophagitis. (authors)

The therapeutic effect of three-dimensional conformal radiation therapy combined with conventional radiotherapy for nasopharyngeal carcinoma

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Liang Feng; Lu Zhonghong; Yao Zhijun; Cao Yongzhen

2011-01-01

Objective: To observe the therapeutic effect of three-dimensional conformal radiation therapy (3DCRT) for nasopharyngeal carcinoma (NPC). Methods: 78 patients with NPC was treated by radiation schedule in two phases. In the first phase, nasopharyngeal lesions and metastases of all patients were treated by three-dimensional conformal radiation therapy (3DCRT) with a fraction of 2-5 Gy daily, 5 day per weeks, total dose 30 Gy. The second phase T1N0 or parts of T2N0 patients were done by Conventional radiotherapy with total dose 55 Gy on two small lateral opposing fields + with total dose 50 Gy on neck on tangential field,adding a 3 cm block. Patients with lymph node metastasis were given 55 Gy on the dacio-neck field (After 40 Gy, two small lateral opposing fields were used to boost the primary tumor while the spinal cord shielded) + with total dose 55 Gy on lower neck on tangential field. The upper bound of designed therapeutic field was set to connect with lower bound of main therapeutic field. Results: Three months after treatment,the rate of CR, PR, SD, PD were 38.5%, 55.1%, 5.1%, 1.3%, Total effective rate (CR+PR) were 93.6%. The 1-year, 2-year, 3-year and 5-year local-regional control rates were 92.3%, 88.5%, 78.2%, 70.5%.The 1-year, 2-year , 3-year and 5-year overall survival rate were 96.2%, 89.7%, 83.3%, 71.8%. Appearing early radiation response is well tolerated and no obviously mouth difficulties and cranial nerve damage observed. Conclusion: Clinical result of early-course three-dimensional conformal radiation therapy (3DCRT) for nasopharyngeal carcinoma (NPC) is good. (authors)

Hepatitis B Virus Reactivation After Three-Dimensional Conformal Radiotherapy in Patients With Hepatitis B Virus-Related Hepatocellular Carcinoma

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Kim, Ji Hoon; Park, Joong-Won; Kim, Tae Hyun; Koh, Dong Wook; Lee, Woo Jin; Kim, Chang-Min

2007-01-01

Purpose: To investigate whether three-dimensional conformal radiotherapy (3D-CRT) influences hepatitis B virus (HBV) reactivation and chronic hepatitis B (CHB) exacerbation in patients with HBV-related hepatocellular carcinoma (HCC). Methods and Materials: Of the 48 HCC patients with HBV who underwent 3D-CRT to the liver, 16 underwent lamivudine therapy before and during 3D-CRT (Group 1) and 32 did not receive antiviral therapy before 3D-CRT (Group 2). To analyze spontaneous HBV reactivation, we included a control group of 43 HCC patients who did not receive any specific treatment for HCC or CHB. Results: The cumulative rate of radiation-induced liver disease for Groups 1 and 2 was 12.5% (2 of 16) and 21.8% (7 of 32), respectively (p > 0.05). The cumulative rate of HBV reactivation was significantly greater in Group 2 (21.8%, 7 of 32) than in Group 1 (0%, 0/16) or the control group (2.3%, 1 of 43; p 0.05 each). The CHB exacerbations in the 4 Group 2 patients had radiation-induced liver disease features but were differentiated by serum HBV DNA changes. Two of these patients required antiviral therapy and effectively recovered with lamivudine therapy. Conclusions: In patients with HBV-related HCC undergoing 3D-CRT, HBV reactivation and consequent CHB exacerbation should be considered in the differential diagnosis of radiation-induced liver disease, and antiviral therapy might be considered for the prevention of liver function deterioration after RT

Radiotherapy-induced secondary cancer risk for breast cancer: 3D conformal therapy versus IMRT versus VMAT

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Lee, Boram; Sung, Jiwon; Yoon, Myonggeun; Lee, Sunyoung

2014-01-01

This study evaluated the secondary cancer risk to various organs due to radiation treatment for breast cancer. Organ doses to an anthropomorphic phantom were measured using a photoluminescent dosimeter (PLD) for breast cancer treatment with 3D conformal radiation therapy (3D-CRT), intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT). Cancer risk based on the measured dose was calculated using the BEIR (Biological Effects of Ionizing Radiation) VII models. The secondary dose per treatment dose (50.4 Gy) to various organs ranged from 0.02 to 0.36 Gy for 3D-CRT, but from 0.07 to 8.48 Gy for IMRT and VMAT, indicating that the latter methods are associated with higher secondary radiation doses than 3D-CRT. The result of the homogeneity index in the breast target shows that the dose homogeneity of 3D-CRT was worse than those of IMRT and VMAT. The organ specific lifetime attributable risks (LARs) to the thyroid, contralateral breast and ipsilateral lung per 100 000 population were 0.02, 19.71, and 0.76 respectively for 3D-CRT, much lower than the 0.11, 463.56, and 10.59 respectively for IMRT and the 0.12, 290.32, and 12.28 respectively for VMAT. The overall estimation of LAR indicated that the radiation-induced cancer risk due to breast radiation therapy was lower with 3D-CRT than with IMRT or VMAT. (paper)

Whole-pelvic radiotherapy with spot-scanning proton beams for uterine cervical cancer: a planning study

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Hashimoto, Shingo; Shibamoto, Yuta; Iwata, Hiromitsu; Ogino, Hiroyuki; Shibata, Hiroki; Toshito, Toshiyuki; Sugie, Chikao; Mizoe, Jun-etsu

2016-01-01

The aim of this study was to compare the dosimetric parameters of whole-pelvic radiotherapy (WPRT) for cervical cancer among plans involving 3D conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), or spot-scanning proton therapy (SSPT). The dose distributions of 3D-CRT-, IMRT-, and SSPT-based WPRT plans were compared in 10 patients with cervical cancer. All of the patients were treated with a prescribed dose of 50.4 Gy in 1.8-Gy daily fractions, and all of the plans involved the same planning target volume (PTV) constrictions. A 3D-CRT plan involving a four-field box, an IMRT plan involving seven coplanar fields, and an SSPT plan involving four fields were created. The median PTV D95% did not differ between the 3D-CRT, IMRT and SSPT plans. The median conformity index 95% and homogeneity index of the IMRT and SSPT were better than those of the 3D-CRT. The homogeneity index of the SSPT was better than that of the IMRT. SSPT resulted in lower median V20 values for the bladder wall, small intestine, colon, bilateral femoral heads, skin, and pelvic bone than IMRT. Comparing the Dmean values, SSPT spared the small intestine, colon, bilateral femoral heads, skin and pelvic bone to a greater extent than the other modalities. SSPT can reduce the irradiated volume of the organs at risk compared with 3D-CRT and IMRT, while maintaining excellent PTV coverage. Further investigations of SSPT are warranted to assess its role in the treatment of cervical cancer.

Long-term urinary toxicity after 3-dimensional conformal radiotherapy for prostate cancer in patients with prior history of transurethral resection

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Sandhu, Ajaypal S.; Zelefsky, Michael J.; Lee, Henry J.; Lombardi, Danna; Fuks, Zvi; Leibel, Steven A.

2000-01-01

Purpose: To report on the long-term urinary morbidity among prostate cancer patients with a prior history of a transurethral resection of the prostate (TURP) treated with high-dose 3-dimensional conformal radiotherapy (3D-CRT). Methods and Materials: Between 1988 and 1997, 1100 patients with clinically localized prostate cancer were treated with 3D-CRT. Of these, 120 patients (8%) were identified as having had a prior TURP and are the subjects of this analysis. The median age was 71 years (range: 49-83 years). The clinical stages of the patients were T1c: 33 (28%); T2a: 38 (32%); T2b: 15 (13%); and T3: 34 (27%). Neoadjuvant androgen ablation therapy was given to 39 (33%). The median radiation dose prescribed to the planning target volume was 75.6 Gy (range: 64.8-81 Gy). The median elapsed time from TURP to initiation of 3D-CRT was 69 months (range: 4-360 months). The median follow-up time was 51 months (range: 18-109 months). Results: Five patients of the 120 with a prior history of TURP (4%) developed a urethral stricture after 3D-CRT which was corrected with dilatation. The 5-year actuarial likelihood of ≥ Grade 2 late urinary toxicities was 9%. No Grade 4 urinary toxicities were observed in this group of patients. Among 110 patients who were completely continent of urine prior to 3D-CRT, 10 (9%) developed stress incontinence requiring 1 pad daily for protection or experienced occasional leakage (not requiring pad protection). The 5-year incidence of ≥ Grade 1 stress incontinence was 18% in patients who developed acute ≥ Grade 2 GU symptoms during the course of 3D-CRT compared to 7% for patients who experienced Grade 1 or no acute urinary symptoms (p = 0.05). The radiation dose (≥75.6 Gy vs. <75.6 Gy), the number of prior TURP procedures, or the volume of resected tissue at the time of TURP had no significant impact on the long-term urinary morbidity outcome. A multivariate analysis demonstrated that the presence of Grade 2 acute urinary symptoms was the

Incidental irradiation of mediastinal and hilar lymph node stations during 3D-conformal radiotherapy for non-small cell lung cancer

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Kepka, Lucyna; Bujko, Krzysztof; Zolciak-Siwinska, Agnieszka; Garmol, Dariusz

2008-01-01

Purpose. To estimate the doses of incidental irradiation in particular lymph node stations (LNS) in different extents of elective nodal irradiation (ENI) in 3D-conformal radiotherapy (3D-CRT) for non-small cell lung cancer (NSCLC). Methods. Doses of radiotherapy were estimated for particular LNS delineated according to the recommendations of the Univ. of Michigan in 220 patients treated using 3D-CRT with different (extended, limited and omitted) extents of ENI. Minimum doses and volumes of LNS receiving 40 Gy or more (V40) were compared for omitted vs. limited+extended ENI and limited vs. extended ENI. Results. For omission of the ENI the minimum doses and V40 for particular LNS were significantly lower than for patients treated with ENI. For the limited ENI group, the minimum doses for LNS 5, 6 lower parts of 3A and 3P (not included in the elective area) did not differ significantly from doses given to respective LNS for extended ENI group. When the V40 values for extended and limited ENI were compared, no significant differences were seen for any LNS, except for group 1/2R, 1/2L. Conclusions. Incidental irradiation of untreated LNS seems play a part in case of limited ENI, but not in cases without ENI. For subclinical disease the delineation of uninvolved LNS 5, 6, and lower parts of 3A, 3P may be not necessary, because these stations receive the substantial part of irradiation incidentally, if LNS 4R, 4L, 7, and ipsilateral hilum are included in the elective area while this is not case for stations 1 and 2

Comparison of dosimetric parameters and toxicity in esophageal cancer patients undergoing 3D conformal radiotherapy or VMAT

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Muench, Stefan; Aichmeier, Sylvia; Duma, Marciana-Nona; Oechsner, Markus; Habermehl, Daniel [TU Muenchen, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Hapfelmeier, Alexander [TU Muenchen, Institute of Medical Statistics and Epidemiology (IMSE), Klinikum rechts der Isar, Muenchen (Germany); Feith, Marcus [TU Muenchen, Department of Visceral Surgery, Klinikum rechts der Isar, Muenchen (Germany); Combs, Stephanie E. [TU Muenchen, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Helmholtz Zentrum Muenchen, Institute of Innovative Radiotherapy (iRT), Oberschleissheim (Germany)

2016-10-15

Volumetric-modulated arc therapy (VMAT) achieves high conformity to the planned target volume (PTV) and good sparing of organs at risk (OAR). This study compares dosimetric parameters and toxicity in esophageal cancer (EC) patients treated with VMAT and 3D conformal radiotherapy (3D-CRT). Between 2007 and 2014, 17 SC patients received neoadjuvant chemoradiation (CRT) with VMAT. Dose-volume histograms and toxicity were compared between these patients and 20 treated with 3D-CRT. All patients were irradiated with a total dose of 45 Gy. All VMAT patients received simultaneous chemotherapy with cisplatin and 5-fluorouracil (5-FU) in treatment weeks 1 and 5. Of 20 patients treated with 3D-CRT, 13 (65 %) also received CRT with cisplatin and 5-FU, whereas 6 patients (30 %) received CRT with weekly oxaliplatin and cetuximab, and a continuous infusion of 5-FU (OE-7). There were no differences in baseline characteristics between the treatment groups. For the lungs, VMAT was associated with a higher V{sub 5} (median 90.1 % vs. 79.7 %; p = 0.013) and V{sub 10} (68.2 % vs. 56.6 %; p = 0.014), but with a lower V{sub 30} (median 6.6 % vs. 11.0 %; p = 0.030). Regarding heart parameters, VMAT was associated with a higher V{sub 5} (median 100.0 % vs. 91.0 %; p = 0.043), V{sub 10} (92.0 % vs. 79.2 %; p = 0.047), and D{sub max} (47.5 Gy vs. 46.3 Gy; p = 0.003), but with a lower median dose (18.7 Gy vs. 30.0 Gy; p = 0.026) and V{sub 30} (17.7 % vs. 50.4 %; p = 0.015). Complete resection was achieved in 16 VMAT and 19 3D-CRT patients. Due to systemic progression, 2 patients did not undergo surgery. The most frequent postoperative complication was anastomosis insufficiency, occurring in 1 VMAT (6.7 %) and 5 3D-CRT patients (27.8 %; p = 0.180). Postoperative pneumonia was seen in 2 patients of each group (p = 1.000). There was no significant difference in 3-year overall (65 % VMAT vs. 45 % 3D-CRT; p = 0.493) or 3-year progression-free survival (53 % VMAT vs. 35 % 3D-CRT; p = 0

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

Class solution to decrease rectal dose in prostate radiotherapy treatments 3D-CRT

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Andres Rodriguez, C.; Tortosa Oliver, R.; Alonso Hernandez, D.; Mari Palacios, A.; Castillo Belmonte, A. del

2011-01-01

This paper contains a method developed in our center with conventional 3D radiotherapy techniques to increase the dose conformation around the target volume in prostate cancer treatments significantly reduced the doses to the rectum. To evaluate the goodness of the method, the results are compared with two classical techniques of treatment.

Does gap-free intensity modulated chemoradiation therapy provide a greater clinical benefit than 3D conformal chemoradiation in patients with anal cancer?

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Dewas, Claire Vautravers; Créhange, Gilles; Maingon, Philippe; Dalban, Cécile; Petitfils, Aurélie; Peignaux, Karine; Truc, Gilles; Martin, Etienne; Khoury, Cédric; Dewas, Sylvain

2012-01-01

Chemoradiation is the standard treatment for anal cancer. 3D conformal radiotherapy (3D-CRT) is usually split in 2 sequences with a therapeutic break (gap) in between. Intensity-modulated radiation therapy (IMRT) makes it possible to reduce treatment time by abandoning this gap. The purpose of this study was to compare outcomes and toxicities in patients treated with either IMRT or 3D-CRT. Between 2004 and 2011, the data of 51 patients treated with exclusive radiotherapy with or without concomitant chemotherapy for non-metastatic anal carcinoma were retrospectively analyzed. Twenty-seven patients were treated with 3D-CRT and 24 patients with IMRT, with a median dose delivered to the tumor of 59.4Gy [30.6-66.6], whatever the radiotherapy technique (p= 0.99). The median follow-up was 40 months [26.4-51.6]. There was no difference between the two groups for response to treatment (p= 0.46). Two-year overall survival, locoregional relapse-free survival and colostomy-free survival rates were 88.5%, 63% and 60.3%, respectively for the IMRT group and 81%, 76.5% and 81.1% for the 3D-CRT group (all NS). Ten patients (37%) in 3D-CRT and 11 patients (45.8%) in IMRT (p= 0.524) had grade 3 acute toxicity. No grade 4 toxicity occurred. Our study suggests that further investigations concerning the use of IMRT to treat cancer of the anus are warranted. IMRT makes it possible to remove the gap, but with no impact on the prognosis. Nonetheless, a longer follow-up is essential to determine whether or not IMRT has an impact on late toxicity, local control and survival compared with conventional 3D-CRT

Estimate of the damage in organs induced by neutrons in three-dimensional conformal radiotherapy

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Benites R, J. L.; Vega C, H. R.; Uribe, M. del R.

2014-08-01

By means of Monte Carlo methods was considered the damage in the organs, induced by neutrons, of patients with cancer that receive treatment in modality of three-dimensional conformal radiotherapy (3D-CRT) with lineal accelerator Varian Ix. The objective of this work was to estimate the damage probability in radiotherapy patients, starting from the effective dose by neutrons in the organs and tissues out of the treatment region. For that a three-dimensional mannequin of equivalent tissue of 30 x 100 x 30 cm 3 was modeled and spherical cells were distributed to estimate the Kerma in equivalent tissue and the absorbed dose by neutrons. With the absorbed dose the effective dose was calculated using the weighting factors for the organ type and radiation type. With the effective dose and the damage factors, considered in the ICRP 103, was considered the probability of damage induction in organs. (Author)

Prospective randomized trail on chrono-chemotherapy + late course three dimensional conformal radio-therapy and conventional chemotherapy plus radiotherapy for nasopharyngeal carcinoma

International Nuclear Information System (INIS)

Jin Feng; Ouyang Jinling; Dong Hongmin; Wu Weili; Chen Haixia; He Zhihui

2005-01-01

Objective: To compare the therapeutic effects, toxic side effects of late-course three dimensional conformal radiotherapy plus chrono-chemotherapy (DDP + 5-FU/CF) and conventional radiotherapy plus chemotherapy for nasopharyngeal carcinoma (NPC). Methods: Eighty -six NPC patients admitted from Feb. 2001 to Jan. 2002 were divided randomly into two groups: 1. Chrono-chemotherapy + late course three dimensional conformal radiotherapy(CCR) group-44 patients were treated by late course three dimensional conformal radio-therapy plus chrono-chemotherapy, and 2. Routine-chemotherapy-radiotherapy (RCR) group-42 patients were treated by routine chemotherapy plus radiotherapy. The patients in CCR and RCR group were comparable in age, KPS, stage and pathology. All patients were treated by combined chemotherapy and radiotherapy, with chemotherapy stared 2 weeks ahead of radiotherapy. Chemotherapy: Braun pump was used in all drug infusions; 1. CCR group-DDP 80 mg/ m 2 starting from 10:00 until 22:00, 5-Fu 750 mg/d/m 2 starting from 22:00 until 10:00 next day, CF 200 mg/d/m 2 starting from 10:00 every day, infused at normal speed. These drugs were given for 3 days, 14 days as one cycle, totally 2 cycle, and 2. RCR group-with the same drugs at the same total dose, only with the difference being DDP and CF given QD, starting from 10:00 but at the normal speed. 5-Fu was given through-out the day and continuously for 3 days, totally for 2 cycles. Radiotherapy: linear accelerator irradiation was given to either group. Composite facio-cervical field + anterior cervical tangential field to D T 40 Gy/4w, followed by the coned down per-auricular field plus anterior tangential field or β beam irradiation. In CCR group, after D T 40gy/4w, late course 3-dimensional conformal radiotherapy (3DCRT) was used to add D T 30Gy/3w. In RCR group, routine radiotherapy of 40 Gy/w was supplemented with 30 Gy/3w. The total dose in either group was 70 Gy/7w at the nasopharynx, D T 60-70 Gy/6-7w at the

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.

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

Volumetric intensity-modulated arc therapy vs. 3-dimensional conformal radiotherapy for primary chemoradiotherapy of anal carcinoma. Effects on treatment-related side effects and survival

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Weber, Hanne Elisabeth; Droege, Leif Hendrik; Hennies, Steffen; Herrmann, Markus Karl; Wolff, Hendrik Andreas [University Medical Center Goettingen, Dept. of Radiotherapy and Radiooncology, Goettingen (Germany); Gaedcke, Jochen [University Medical Center Goettingen, Dept. of General Surgery, Goettingen (Germany)

2015-11-15

Primary chemoradiotherapy (CRT) is the standard treatment for locally advanced anal carcinoma. This study compared volumetric intensity-modulated arc therapy (VMAT) to 3-dimensional conformal radiotherapy (3DCRT) in terms of treatment-related side effects and survival. From 1992-2014, 103 consecutive patients with anal carcinoma UICC stage I-III were treated. Concomitant CRT consisted of whole pelvic irradiation, including the iliac and inguinal lymph nodes, with 50.4 Gy (1.8 Gy per fractions) by VMAT (n = 17) or 3DCRT (n = 86) as well as two cycles of 5-fluorouracil and mitomycin C. Acute organ and hematological toxicity were assessed according to the Common Terminology Criteria (CTC) for Adverse Events version 3.0. Side effects ≥ grade 3 were scored as high-grade toxicity. High-grade acute organ toxicity CTC ≥ 3 (P < 0.05), especially proctitis (P = 0.03), was significantly reduced in VMAT patients. The 2-year locoregional control (LRC) and disease-free survival (DFS) were both 100 % for VMAT patients compared with 80 and 73 % for 3DCRT patients. VMAT was shown to be a feasible technique, achieving significantly lower rates of acute organ toxicity and promising results for LRC and DFS. Future investigations will aim at assessing the advantages of VMAT with respect to late toxicity and survival after a prolonged follow-up time. (orig.) [German] Die primaere Radiochemotherapie (RCT) gilt als Standardtherapie fuer lokal fortgeschrittene Analkarzinome. In dieser Studie wurde die volumetrisch modulierte Rotationstherapie (''volumetric intensity-modulated arc therapy'', VMAT) mit der klassischen dreidimensionalen konformalen Radiotherapie (3DCRT) hinsichtlich therapieassoziierter Nebenwirkungen und Ueberleben verglichen. Von 1992-2014 wurden 103 aufeinanderfolgende Patienten mit einem Analkarzinom im UICC-Stadium I-III behandelt. Die kombinierte RCT bestand aus der Bestrahlung des gesamten Beckens inklusive der iliakalen und der inguinalen

Geometrical uncertainty margins in 3D conformal radiotherapy in the pediatric age group

International Nuclear Information System (INIS)

Eldebawy, E.; Attalla, E.; Eldesoky, I.; Zaghloul, M.S.

2011-01-01

To evaluate set-up variation of pediatric patients undergoing 3D conformal radiotherapy (3DCRT) using electronic portal image device (EPID), in an effort to evaluate the adequacy of the planning target volume (PTV) margin employed for the 3DCRT treatment of pediatric patients. Materials and methods: Set-up data was collected from 48 pediatric patients treated with 3D CRT-for head and neck (31 patients), abdomino-pelvic (9 patients) and chest (8 patients) sites during the period between September 2008 and February 2009. A total of 358 images obtained by EPID were analyzed. The mean (M) and standard deviation (SD) for systematic and random errors were calculated and the results were analyzed. Results: All images were studied in anterior and lateral portals. The systematic errors along longitudinal, lateral and vertical directions in all patients showed an M equal to 1.9,1.6, and 1.6 mm with SD of 1.8,1.4, and 1.8 mm, respectively; (head and neck cases: M equal to 1.5,1.2, and 1.6 mm with SD 1.4,1.2, and 1.8 mm; chest cases: M equal to 2.5,1.8, and 0.8 mm with SD 2.7,1.7, and 1.2 mm, abdomen-pelvic cases: M equal to 2.9,2.8 and 2.3 mm with SD 1.6,1.2, and 2.3 mm). Similarly, the random errors for all patients showed SD of 1.9,1.6, and 1.8 mm, respectively (head and neck cases: SD 1.7,1.3, and 1.5 mm; chest cases: SD 1.2,1.9, and 2.5 mm; abdomino-pelvic cases SD 2.5, 2, and 2.4 mm, respectively). Using Van Herk's formula the suggested (PTV) margin around the clinical target volume (CTV) of 5.5 mm appears to be adequate. Conclusion: The ranges of set-up errors are site specific and depends on many factors

Sexual Function After Three-Dimensional Conformal Radiotherapy for Prostate Cancer: Results From a Dose-Escalation Trial

International Nuclear Information System (INIS)

Wielen, Gerard J. van der; Putten, Wim van; Incrocci, Luca

2007-01-01

Purpose: The purpose of this study is to provide information about sexual function (SF) after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer while taking important factors into account that influence SF. Methods and Materials: Between June 1997 and February 2003, a total of 268 patients from a randomized dose-escalation trial comparing 68 Gy and 78 Gy agreed to participate in an additional part of the trial that evaluated SF. Results: At baseline 28% of patients had erectile dysfunction (ED). After 1 year, 27% of the pretreatment potent patients had developed ED. After 2 years this percentage had increased to 36%. After 3 years it almost stabilized at 38%. Satisfaction with sexual life was significantly correlated with ED. After 2 years one third of the pre-treatment potent patients still had considerable to very much sexual desire and found sex (very) important. No significant differences were found between the two dose-arms. Potency aids were used on a regular base by 14% of the patients. Conclusion: By taking adjuvant hormonal therapy (HT), HT during follow-up and potency aids into account, we found a lower percentage of ED after 3D-CRT than reported in previous prospective studies. A large group of patients still had sexual desire, considered sex important and 14% used potency aids after 3D-CRT

Predictive factors of gastroduodenal toxicity in cirrhotic patients after three-dimensional conformal radiotherapy for hepatocellular carcinoma

International Nuclear Information System (INIS)

Kim, Haeyoung; Lim, Do Hoon; Paik, Seung Woon; Yoo, Byung Chul; Koh, Kwang Gheol; Lee, Joon Hyoek; Choi, Moon Seok; Park, Won; Park, Hee Chul; Huh, Seung Jae; Choi, Doo Ho; Ahn, Yong Chan

2009-01-01

Background and purpose: To identify predictive factors for the development of gastroduodenal toxicity (GDT) in cirrhotic patients treated with three-dimensional conformal radiotherapy (3D-CRT) for hepatocellular carcinoma (HCC). Materials and methods: We retrospectively analyzed dose-volume histograms (DVHs) and clinical records of 73 cirrhotic patients treated with 3D-CRT for HCC. The median radiation dose was 36 Gy (range, 30-54 Gy) with a daily dose of 3 Gy. The grade of GDT was defined by the Common Toxicity Criteria Version 2. The predictive factors of grade 3 GDT were identified. Results: Grade 3 GDT was found in 9 patients. Patient's age and the percentage of gastroduodenal volume receiving more than 35 Gy (V 35 ) significantly affected the development of grade 3 GDT. Patients over 50 years of age developed grade 3 GDT more frequently than patients under 50 years of age. The risk of grade 3 GDT grew exponentially as V 35 increased. The 1-year actuarial rate of grade 3 GDT in patients with V 35 35 ≥5% (4% vs. 48%, p 35 were the most predictive factors for the development of grade 3 GDT in patients treated with RT.

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

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

Design and implementation of a rotational radiotherapy technique for breast cancer treatment and their comparison with 3-D-Crt irradiation technique

International Nuclear Information System (INIS)

Gutierrez M, J. G.; Lopez V, A.; Rivera M, T.; Velazquez T, J. J.; Adame G, C. S.; Rubio N, O.; Chagoya G, A.; Hernandez G, J. C.

2015-10-01

Breast cancer is one of oncological diseases worldwide, as well in Mexico, which causes even more deaths than cervical cancer; this condition is the second death cause in women aged 30-54 years and threatens all socio-economic groups. The treatment is highly dependent on the stage which is detected and based on protocols that include a combination of surgery, chemotherapy and radiotherapy. This paper studies the main irradiation technique for patients with mastectomy, breast full cycle (irradiation of the chest well and supraclavicular nodes) in their mode Three Dimensional - Conformal Radiation Therapy (3-D-Crt), and compared with the Volumetric Modulated Arc Therapy (VMAT) technique proposed in this paper. In both techniques the prescription was 50 Gy divided into 25 fractions. The techniques were applied in three female patients (being an initial study) with disease of the left side, the target volume and organs at risk were delineated by the medical treating radiation oncologist, the planning system used was Eclipse version 10; for quantitative comparison of both plans indexes of homogeneity were used, con formality, the target volume coverage and normal tissue, sub factors and overdosing, the conformation number and coverage quality. They were evaluated and compared the media, maximum and minimum dose of the organs at risk, based on the fact that the coverage of the target volume, dose gradient and dose at risk organs are acceptable (prescription dose greater that 90% coverage, gradient less that 20% and organs at risk in accordance with the Quantec limitations for both versions). (Author)

[Technique of complex mammary irradiation: Mono-isocentric 3D conformational radiotherapy and helical tomotherapy].

Science.gov (United States)

Vandendorpe, B; Guilbert, P; Champagne, C; Antoni, T; Nguyen, T D; Gaillot-Petit, N; Servagi Vernat, S

2017-12-01

To evaluate the dosimetric contribution of helical tomotherapy for breast cancers compared with conformal radiotherapy in mono-isocentric technique. For 23 patients, the dosimetric results in mono-isocentric 3D conformational radiotherapy did not satisfy the constraints either of target volumes nor organs at risk. A prospective dosimetric comparison between mono-isocentric 3D conformational radiotherapy and helical tomotherapy was therefore carried out. The use of helical tomotherapy showed a benefit in these 23 patients, with either an improvement in the conformity index or homogeneity, but with an increase in low doses. Of the 23 patients, two had pectus excavatum, five had past thoracic irradiation and two required bilateral irradiation. The other 14 patients had a combination of morphology and/or indication of lymph node irradiation. For these patients, helical tomotherapy was therefore preferred to mono-isocentric 3D conformational radiotherapy. Tomotherapy appears to provide better homogeneity and tumour coverage. This technique of irradiation may be justified in the case of morphological situations such as pectus exavatum and in complex clinical situations. In other cases, conformal radiotherapy in mono-isocentric technique remains to be favoured. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

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

Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer

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Ana Paula Diniz Fortuna Poli

2016-02-01

Full Text Available Abstract Objective: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT for prostate cancer. Materials and Methods: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. Results: The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation ( p = 0.037. A baseline rectal volume superior to 70 cm3 had a significant influence on the prostate motion in the anteroposterior direction ( p = 0.045. Conclusion: The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm3. Therefore, the treatment of patients with a rectal volume > 70 cm3 should be re-planned with appropriate rectal preparation.

Estimate of the damage in organs induced by neutrons in three-dimensional conformal radiotherapy; Estimacion del dano en organos inducido por neutrones en radioterapia conformada en 3D

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Benites R, J. L. [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calzada de la Cruz 118 sur, 63000 Tepic, Nayarit (Mexico); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Uribe, M. del R., E-mail: jlbenitesr@prodigy.net.mx [Instituto Tecnico Superior de Radiologia, Calle Leon No. 129, 63000 Tepic, Nayarit (Mexico)

2014-08-15

By means of Monte Carlo methods was considered the damage in the organs, induced by neutrons, of patients with cancer that receive treatment in modality of three-dimensional conformal radiotherapy (3D-CRT) with lineal accelerator Varian Ix. The objective of this work was to estimate the damage probability in radiotherapy patients, starting from the effective dose by neutrons in the organs and tissues out of the treatment region. For that a three-dimensional mannequin of equivalent tissue of 30 x 100 x 30 cm{sup 3} was modeled and spherical cells were distributed to estimate the Kerma in equivalent tissue and the absorbed dose by neutrons. With the absorbed dose the effective dose was calculated using the weighting factors for the organ type and radiation type. With the effective dose and the damage factors, considered in the ICRP 103, was considered the probability of damage induction in organs. (Author)

Conformal radiotherapy: principles and classification

International Nuclear Information System (INIS)

Rosenwald, J.C.; Gaboriaud, G.; Pontvert, D.

1999-01-01

'Conformal radiotherapy' is the name fixed by usage and given to a new form of radiotherapy resulting from the technological improvements observed during the last ten years. While this terminology is now widely used, no precise definition can be found in the literature. Conformal radiotherapy refers to an approach in which the dose distribution is more closely 'conformed' or adapted to the actual shape of the target volume. However, the achievement of a consensus on a more specific definition is hampered by various difficulties, namely in characterizing the degree of 'conformality'. We have therefore suggested a classification scheme be established on the basis of the tools and the procedures actually used for all steps of the process, i.e., from prescription to treatment completion. Our classification consists of four levels: schematically, at level 0, there is no conformation (rectangular fields); at level 1, a simple conformation takes place, on the basis of conventional 2D imaging; at level 2, a 3D reconstruction of the structures is used for a more accurate conformation; and level 3 includes research and advanced dynamic techniques. We have used our personal experience, contacts with colleagues and data from the literature to analyze all the steps of the planning process, and to define the tools and procedures relevant to a given level. The corresponding tables have been discussed and approved at the European level within the Dynarad concerted action. It is proposed that the term 'conformal radiotherapy' be restricted to procedures where all steps are at least at level 2. (author)

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.

Neoadjuvant androgen deprivation and prostate gland shrinkage during conformal radiotherapy

International Nuclear Information System (INIS)

Sanguineti, Giuseppe; Marcenaro, Michela; Franzone, Paola; Foppiano, Franca; Vitale, Vito

2003-01-01

Purpose: The shrinking effect of 3-month neoadjuvant androgen deprivation (NAD) on preradiotherapy prostate gland volume is well documented. However, recently, it has been shown that the cancerous prostate gland keeps shrinking up to 12 months after NAD start. Thus, if such a reduction is not taken into account, a larger than planned portion of the surrounding normal tissues might shift in the high-dose region during conformal radiotherapy (3DCRT) course. The present study was undertaken to quantify this issue. Materials and Methods: Prostate gland volume reduction between planning CT (plCT) and the last week of 3DCRT (tmtCT) was prospectively assessed in 33 consecutive patients with localized prostate carcinoma. The median time interval between plCT and tmtCT was 2.5 months (2.1-2.7 months). A single observer was asked to draw on each slice prostate gland volume as appropriate. The observer was 'blind' to the timing of CT (plCT vs. tmtCT). In order to estimate intra-observer variability, prostate gland delineation was repeated twice for each data set. Mean prostate gland change, plCT and tmtCT cumulative dose volume histogram (DVH) calculations for the rectum were analyzed for each patient. Results were correlated to AD status and its duration before plCT. Means were compared by non-parametric rank tests. Results: Based on an internal protocol, 14 patients (42%) did not receive AD, while 19 patients (58%) had undergone neoadjuvant and concomitant AD. The median duration of AD before plCT ranged from 0.2 to 6 months (median: 2.9 months). Although individual data were highly variable, compared to plCT volume, mean prostate gland volume change at the end of 3DCRT was similar for patients receiving (-7.3%) or not (-7%) androgen deprivation (P=0.77). However, within the group of patients treated with hormones, patients starting AD within 3 months from plCT had a significantly larger reduction in prostate volume (-14.2%) than patients with longer NAD duration (-1.1%, P

A Comparative Dosimetric Study of Adjuvant 3D Conformal Radiotherapy for Operable Stomach Cancer Versus AP-PA Conventional Radiotherapy in NCI-Cairo

International Nuclear Information System (INIS)

El-Hossiny, H.A.; Diab, N.A.; El-Taher, M.M.

2009-01-01

This study was to compare this multiple field conformal technique to the AP-PA technique with respect to target volume coverage and dose to normal tissues. Materials and Methods: Seventeen patients with stages II-III denocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy presented to radiotherapy department in National Cancer Institute, Cairo in period between February 2009 to March 2010 using 3D conformal radiotherapy technique that consisted of a mono isocentric arrangement employing 4-6 radiation fields. For each patient, a second radiotherapy treatment plan was done using an antroposterior (AP-PA) fields, the two techniques were then compared using dose volume histogram (DVH) analysis. Results: Comparing different DVHs, it was found that the planning target volume (PTV) was adequately covered in both (3D and 2D) plans while the left kidney and spinal cord demonstrate lower radiation doses on using the conformal technique. The liver doses is higher in the 3D tecq, but still well below liver tolerance. Conclusions: Both 3D conformal radiotherapy and AP-PA conventional techniques doses are within range of normal tissues tolerance. Regarding the left kidney and spinal cord the 3D conformal radiotherapy is superior than the AP-PA conventional techniques but with higher doses to the liver in the 3D conformal radiotherapy compared to the AP-PA conventional techniques

Clinical Applications of 3-D Conformal Radiotherapy

Science.gov (United States)

Miralbell, Raymond

Although a significant improvement in cancer cure (i.e. 20% increment) has been obtained in the last 2-3 decades, 30-40% of patients still fail locally after curative radiotherapy. In order to improve local tumor control rates with radiotherapy high doses to the tumor volume are frequently necessary. Three-dimensional conformal radiation therapy (3-D CRT) is used to denote a spectrum of radiation planning and delivery techniques that rely on three-dimensional imaging to define the target (tumor) and to distinguish it from normal tissues. Modern, high-precision radiotherapy (RT) techniques are needed in order to implement the goal of optimal tumor destruction delivering minimal dose to the non-target normal tissues. A better target definition is nowadays possible with contemporary imaging (computerized tomography, magnetic resonance imaging, and positron emission tomography) and image registration technology. A highly precise dose distributions can be obtained with optimal 3-D CRT treatment delivery techniques such as stereotactic RT, intensity modulated RT (IMRT), or protontherapy (the latter allowing for in-depth conformation). Patient daily set-up repositioning and internal organ immobilization systems are necessary before considering to undertake any of the above mentioned high-precision treatment approaches. Prostate cancer, brain tumors, and base of skull malignancies are among the sites most benefitting of dose escalation approaches. Nevertheless, a significant dose reduction to the normal tissues in the vicinity of the irradiated tumor also achievable with optimal 3-D CRT may also be a major issue in the treatment of pediatric tumors in order to preserve growth, normal development, and to reduce the risk of developing radiation induced diseases such as cancer or endocrinologic disorders.

Metastatic breast cancer in the eye and orbit, use three-dimensional conformal radiotherapy. Our first experience

International Nuclear Information System (INIS)

Correa Pablos, Tamara; Caceres Toledo, Maria

2009-01-01

The eye and orbit metastases are a significant clinical problem, both by the inability and the deterioration in the quality of life that occur. The most common malignant tumors in the eye and orbit is metastasis. Cancer breast cancer is the most common tumor metastatic to the eye and orbit in a 40% and 50% of cases according to different series. With the introduction of Three-Dimensional Conformal Radiotherapy (3D-CRT) in our hospital from In 2007 we were able to treat patients with cancer different regions with the technique (2D) was impossible because caused irreparable damage to surrounding healthy tissue in this way thanks to potential of 3D technology to shape the planning volume will ensure greater protection for critical organs. (Author)

Domestic comparison of radiation treatment techniques for breast cancer: 3D-CRT, IMRT and VMAT

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Lee, Bo Ram; Yoon, Myong Geun [Dept. of Bio-convergence Engineering, College of Health Science, Korea University, Seoul (Korea, Republic of); Lee, Sun Young [Dept. of Radiation Oncology, Yusung Sun Medical Center, Daejeon (Korea, Republic of)

2013-09-15

The purpose of this study is to compare method in the treatment of breast cancer using dose index. And, it is to find the optimized treatment technique to the patient. The phantom filled with tissue-equivalent material were used simulation and treatment as techniques of 3D-CRT, IMRT, VMAT was planned using Eclipse v10. By using HI(homogeneity index), CI(Conformity index), OE (Organ equivalent dose), EAR(Excess Absolute Risk), were assessed for each treatment plans. HI and CI of 3D-CRT, IMRT, VMAT were calculated 16.89, 11.21, 9.55 and 0.59, 0.61, 0.83. The organ average doses of Lt lung, Rt lung, liver, heart, esophagus, cord, Lt breast, trachea and stomach were 0.01 ∼ 2.02 Gy, 0.36 ∼ 5.01 Gy, 0.25 ∼ 2.49 Gy, 0.14 ∼ 6.92 Gy, 0.03 ∼ 2.02 Gy, 0.01 ∼ 1.06 Gy, 0.25 ∼ 6.08 Gy, 0.08 ∼ 0.59 Gy, 0.01 ∼ 1.34 Gy, respectively. The OED, EAR of the IMRT and VMAT show higher than 3D-CRT. As the result of this study, we could confirm being higher dose index(HI, CI) in IMRT and VMAT than 3D-CRT, but doses of around normal organs was higher IMRT, VMAT than 3D-CRT.

Impact of Different CT Slice Thickness on Clinical Target Volume for 3D Conformal Radiation Therapy

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Prabhakar, Ramachandran; Ganesh, Tharmar; Rath, Goura K.; Julka, Pramod K.; Sridhar, Pappiah S.; Joshi, Rakesh C.; Thulkar, Sanjay

2009-01-01

The purpose of this study was to present the variation of clinical target volume (CTV) with different computed tomography (CT) slice thicknesses and the impact of CT slice thickness on 3-dimensional (3D) conformal radiotherapy treatment planning. Fifty patients with brain tumors were selected and CT scans with 2.5-, 5-, and 10-mm slice thicknesses were performed with non-ionic contrast enhancement. The patients were selected with tumor volume ranging from 2.54 cc to 222 cc. Three-dimensional treatment planning was performed for all three CT datasets. The target coverage and the isocenter shift between the treatment plans for different slice thickness were correlated with the tumor volume. An important observation from our study revealed that for volume 25 cc, the target underdosage was less than 6.7% for 5-mm slice thickness and 8% for 10-mm slice thickness. For 3D conformal radiotherapy treatment planning (3DCRT), a CT slice thickness of 2.5 mm is optimum for tumor volume 25 cc

The evolution of rectal and urinary toxicity and immune response in prostate cancer patients treated with two three-dimensional conformal radiotherapy techniques

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Vranova, Jana; Vinakurau, Stepan; Richter, Jan; Starec, Miroslav; Fiserova, Anna; Rosina, Jozef

2011-01-01

Our research compared whole pelvic (WP) and prostate-only (PO) 3-dimensional conformal radiotherapy (3DCRT) techniques in terms of the incidence and evolution of acute and late toxicity of the rectum and urinary bladder, and identified the PTV-parameters influencing these damages and changes in antitumor immune response. We analyzed 197 prostate cancer patients undergoing 3DCRT for gastrointestinal (GI) and genitourinary (GU) toxicities, and conducted a pilot immunological study including flow cytometry and an NK cell cytotoxicity assay. Acute and late toxicities were recorded according to the RTOG and the LENT-SOMA scales, respectively. Univariate and multivariate analyses were conducted for factors associated with toxicity. In the WP group, an increase of acute rectal toxicity was observed. A higher incidence of late GI/GU toxicity appeared in the PO group. Only 18 patients (WP-7.76% and PO-11.11%) suffered severe late GI toxicity, and 26 patients (WP-11.21% and PO-16.05%) severe late GU toxicity. In the majority of acute toxicity suffering patients, the diminution of late GI/GU toxicity to grade 1 or to no toxicity after radiotherapy was observed. The 3DCRT technique itself, patient age, T stage of TNM classification, surgical intervention, and some dose-volume parameters emerged as important factors in the probability of developing acute and late GI/GU toxicity. The proportion and differentiation of NK cells positively correlated during 3DCRT and negatively so after its completion with dose-volumes of the rectum and urinary bladder. T and NKT cells were down-regulated throughout the whole period. We found a negative correlation between leukocyte numbers and bone marrow irradiated by 44-54 Gy and a positive one for NK cell proportion and doses of 5-25 Gy. The acute GU, late GU, and GI toxicities up-regulated the T cell (CTL) numbers and NK cytotoxicity. Our study demonstrates the association of acute and late damage of the urinary bladder and rectum, with

Importance of protocol target definition on the ability to spare normal tissue: An IMRT and 3D-CRT planning comparison for intraorbital tumors

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Hein, Patrick A.; Gladstone, David J.; Bellerive, Marc R.; Hug, Eugen B.

2005-01-01

Purpose: We selected five intraorbital tumor sites that are frequently found in clinical practice in children diagnosed with orbital rhabdomyosarcoma and performed three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated photon radiotherapy (IMRT) planning. Results of target coverage and doses to critical structures were compared. The goal of this study was to evaluate and to document realistic expectations as to organ-sparing capabilities of modern radiation therapy planning technologies with a focus on lens-sparing irradiation. Furthermore, we investigated potential added benefits of IMRT compared with 3D-CRT and the influence of protocol volume criteria definitions on the ability to obtain normal tissue dose sparing using the orbit as an example of a complex anatomic site. Methods and Materials: The five intraorbital tumor sites were placed retrobulbar, temporal, nasal, in the upper inner and upper outer quadrant, the latter two more complex in shape. Gross tumor volume (GTV), clinical target volume (CTV), and planning target volume (PTV) were defined in image-fused computed tomography and magnetic resonance data sets. 3D-CRT and IMRT photon plans, using equal beam angles and collimation for direct comparison, were designed to 45 Gy prescription dose according to Intergroup Rhabdomyosarcoma Study Group-D9602 (IRSG-D9602) protocol (Intergroup Rhabdomyosarcoma Study V [IRS-V] protocol) for Stage I, Clinical Group 3 orbital rhabdomyosarcoma. To compare the impact of changed target definitions in IMRT planning, additional IMRT plans were generated using modified volume and dose coverage criteria. The minimum dose constraint (95%) of the PTV was substituted by a required minimum volume coverage (95%) with the prescribed dose. Dose-volume histograms (DVHs) were obtained, including target volumes, lens, optic nerves, optic chiasm, lacrimal gland, bony orbit, pituitary gland, frontal and temporal lobes. Results: Protocol target volume coverage criteria

3D Conformal radiotherapy for gastric cancer-results of a comparative planning study

International Nuclear Information System (INIS)

Leong, Trevor; Willis, David; Joon, Daryl Lim; Condron, Sara; Hui, Andrew; Ngan, Samuel Y.K.

2005-01-01

Background and purpose: Many radiation oncologists are reluctant to use anteroposterior-posteroanterior (AP-PA) field arrangements when treating gastric cancer with adjuvant postoperative radiotherapy due to concerns about normal tissue toxicity, particularly in relation to the kidneys and spinal cord. In this report, we describe a multiple-field conformal radiotherapy technique, and compare this technique to the more commonly used AP-PA technique that was used in the recently reported Intergroup study (INT0116). Materials and methods: Fifteen patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy using a standardised 3D conformal radiotherapy technique that consisted of a 'split-field', mono-isocentric arrangement employing 6 radiation fields. For each patient, a second radiotherapy treatment plan was generated utilising AP-PA fields. The two techniques were then compared for target volume coverage and dose to normal tissues using dose volume histogram (DVH) analysis. Results: The conformal technique provides more adequate coverage of the target volume with 99% of the planning target volume (PTV) receiving 95% of the prescribed dose, compared to 93% using AP-PA fields. Comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the conformal technique, and although the liver dose is higher, it is still well below liver tolerance. Conclusions: 3D conformal radiotherapy produces superior dose distributions and reduced radiation doses to the kidneys and spinal cord compared to AP-PA techniques, with the potential to reduce treatment toxicity

Clinical application analysis of 3D-CRT methods using tomography

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Cho, Kang Chul; Kyum, Hun Kyum; Kim, Joo Ho; Ahn, Seung Kwon; Lee, Sang Kyoo; Yoon, Jong Won; Cho, Jeong Hee [Dept. of Radiation Oncology, Yonsei Cancer Center, Yonsei University Health System, Seoul (Korea, Republic of); Lee, Jong Seok; Yoo, Beong Gyu [Dept. of Radiotechnology, Wonkwang Health Science University, Iksan (Korea, Republic of)

2013-12-15

This study investigates the case of clinical application for TomoDirect 3D-CRT(TD-3D) and TomoHelical 3D-CRT(TH-3D) with evaluating dose distribution for clinical application in each case. Treatment plans were created for 8 patients who had 3 dimensional conformal radiation therapy using TD-3D and TH-3D mode. Each patients were treated for sarcoma, CSI(craniospinal irradiation), breast, brain, pancreas, spine metastasis, SVC syndrome and esophagus. DVH(dose volume histogram) and isodose curve were used for comparison of each treatment modality. TD-3D shows better dose distribution over the irradiation field without junction effect because TD-3D was not influenced by target length for sarcoma and CSI case. In breast case, dosimetric results of CTV, the average value of D 99%, D 95% were 49.2±0.4 Gy, 49.9±0.4 Gy and V 105%, V 110% were 0%, respectively. TH-3D with the dosimetric block decreased dose of normal organ in brain, pancreas, spine metastasis case. SCV syndrome also effectively decreased dose of normal organ by using dose block to the critical organs(spinal cord <38 Gy). TH-3D combined with other treatment modalities was possible to boost irradiation and was total dose was reduced to spinal cord in esophagus case(spinal cord <45 Gy, lung V 20 <20%). 3D-CRT using Tomotherapy could overcomes some dosimetric limitations, when we faced Conventional Linac based CRT and shows clinically proper dose distribution. In conclusion, 3D-CRT using Tomotherapy will be one of the effective 3D-CRT techniques.

Sucralfate versus mesalazine versus hydrocortisone in the prevention of acute radiation proctitis during conformal radiotherapy for prostate carcinoma. A randomized study.

Science.gov (United States)

Sanguineti, Giuseppe; Franzone, Paola; Marcenaro, Michela; Foppiano, Franca; Vitale, Vito

2003-07-01

To assess whether the topical use of steroids or 5-aminosalicylic acid (5-ASA) is superior to sucralfate in preventing acute rectal toxicity during three-dimensional conformal radiotherapy (3DCRT) to 76 Gy. Patients undergoing 3DCRT for prostate carcinoma at our institution were offered to be randomized to sucralfate 3 g in 15 ml suspension enema (Antepsin, mesalazine 4 g gel enema (Enterasyn, or hydrocortisone 100 mg foam enema (Colifoam. Randomization was blind to the treating physician but not to the patient. Sucralfate was chosen as control arm. Topical treatment had to be performed once daily, starting on day 1 of 3DCRT. Acute rectal toxicity was scored weekly according to RTOG criteria. Time to occurrence of grade 2+ acute rectal toxicity was taken as endpoint. The trial was opened in August 1999, and after the first 24 patients had been treated, arm 2 was discontinued because of eight patients receiving mesalazine, seven actually developed acute rectal toxicity (five patients grade 3 and two patients grade 2). Until May 2001, 134 consecutive patients were randomly assigned to sucralfate (63 patients), mesalazine (eight patients) or hydrocortisone (63 patients). The cumulative incidence of acute rectal toxicity at the end of treatment by arm is 61.9 +/- 6.1%, 87.5 +/- 11.7%, and 52.4 +/- 6.2% for arms 1, 2, and 3, respectively. The difference between the mesalazine group and the sucralfate group is highly significant (hazard ratio [HR] 2.5, 95% confidence interval [CI] 1.1-5.7; p = 0.03). At both uni- and multivariate analysis taking into account several patients and treatment covariates, the difference between hydrocortisone and sucralfate is not significant (HR 0.7, 95% CI 0.5-1.2; p = 0.2). Topical mesalazine is contraindicated during radiotherapy. Hydrocortisone enema is not superior to sucralfate in preventing acute rectal toxicity.

Results of induction chemotherapy followed by three-dimensional conformal radiotherapy and concurrent weekly paclitaxel for stage III non-small cell lung cancer

International Nuclear Information System (INIS)

Wang Weihua; Bao Yong; Chen Ming; Zhang Li; Xu Guangchuan; Li Kaixin

2008-01-01

Objective: To evaluate the toxicity and efficacy of induction chemotherapy (ICT) followed by three-dimensional conformal radiotherapy (3DCRT) plus concurrent weekly paclitaxel for inoperable non-small cell lung cancer (NSCLC). Methods: Patients with stage III NSCLC in favorable conditions were treated with 2 to 4 cycles of carboplatin (AUC=5-6, d1) combined with paclitaxel (175 mg/m 2 , d1), then followed by weekly paclitaxel (40 mg/m 2 ) and concurrent 3DCRT within 34 weeks. The prescription dose of radiotherapy was given as high as possible while total lung V 20 ≤31% and total dose of the spinal cord ≤50 Gy. Results: ICT was well tolerated. During the concurrent chemoradiotherapy,the treatment of 4 patients was ended ahead of the schedule because of severe pulmonary and cardiac toxicities; the treatment of 2 patients was delayed for 7 and 12 days because of fatigue. Leucopenia(33/56) was in grade 1-2 except 1 patient in grade 3. Lymphocytopenia was severe (54/56,42 in grade 3). Three patients developed grade 3 acute radiation-induced esophagitis, and 3 developed grade 3-4 radiation-induced pneumonitis. There was one patients each who developed grade 2,3, and 4 late esophageal damage, respectively. Nine developed grade 2 pulmonary fibrosis. The overall response rate was 69.7%. The 1-year overall survival rate was 72.3%. The 1-year local progression-free survival rate was 62.7%. Conclusions: The schedule of ICT followed by weekly paclitaxel and concurrent 3DCRT can be well tolerated by most of the favorable patients with stage III NSCLC, and the toxicity is tolerable. Results of this study are encouraging, though long-term results should be followed up. (authors)

Genital marginal failures after intensity-modulated radiation therapy (IMRT) in squamous cell anal cancer: no higher risk with IMRT when compared to 3DCRT.

Science.gov (United States)

Dell'Acqua, V; Kobiela, J; Kraja, F; Leonardi, M C; Surgo, A; Zerella, M A; Arculeo, S; Fodor, C; Ricotti, R; Zampino, M G; Ravenda, S; Spinoglio, G; Biffi, R; Bazani, A; Luraschi, R; Vigorito, S; Spychalski, P; Orecchia, R; Glynne-Jones, R; Jereczek-Fossa, B A

2018-03-28

Intensity-modulated radiotherapy (IMRT) is considered the preferred option in squamous cell canal cancer (SCAC), delivering high doses to tumor volumes while minimizing dose to surrounding normal tissues. IMRT has steep dose gradients, but the technique is more demanding as deep understanding of target structures is required. To evaluate genital marginal failure in a cohort of patients with non-metastatic SCAC treated either with IMRT or 3DCRT and concurrent chemotherapy, 117 patients with SCAC were evaluated: 64 and 53 patients were treated with IMRT and 3DCRT techniques, respectively. All patients underwent clinical and radiological examination during their follow-up. Tumor response was evaluated with response evaluation criteria in solid tumors v1.1 guideline on regular basis. All patients' data were analyzed, and patients with marginal failure were identified. Concomitant chemotherapy was administered in 97 and 77.4% of patients in the IMRT and 3DCRT groups, respectively. In the IMRT group, the median follow-up was 25 months (range 6-78). Progressive disease was registered in 15.6% of patients; infield recurrence, distant recurrence and both infield recurrence and distant recurrence were identified in 5, 4 and 1 patient, respectively. Two out of 64 patients (3.1%) had marginal failures, localized at vagina/recto-vaginal septum and left perineal region. In the 3DCRT group, the median follow-up was 71.3 months (range 6-194 months). Two out of 53 patients (3.8%) had marginal failures, localized at recto-vaginal septum and perigenital structures. The rate of marginal failures was comparable in IMRT and 3DCRT groups (χ 2 test p = 0.85). In this series, the use of IMRT for the treatment of SCAC did not increase the rate of marginal failures offering improved dose conformity to the target. Dose constraints should be applied with caution-particularly in females with involvement of the vagina or the vaginal septum.

Acute gastrointestinal, genitourinary, and dermatological toxicity during dose-escalated 3D-conformal radiation therapy (3DCRT) using an intrarectal balloon for prostate gland localization and immobilization

International Nuclear Information System (INIS)

Woel, Rosemonde; Beard, Clair; Chen, Ming-Hui; Hurwitz, Mark; Loffredo, Marian; McMahon, Elizabeth; Ching, Jane; Lopes, Lynn; D'Amico, Anthony V.

2005-01-01

Purpose: We determined the acute gastrointestinal (GI), genitourinary (GU), and dermatologic (D) toxicity during dose-escalated three-dimensional conformal radiation therapy (3DCRT). A modified intrarectal balloon (Medrad) was used for prostate gland localization and immobilization. Methods: Forty-six men with clinical category T1c to T3a, and at least one high-risk feature (PSA >10, Gleason ≥7, or MRI evidence of extracapsular extension or seminal vesical invasion) comprised the study cohort. Treatment consisted of hormonal therapy and 4-field 3DCRT using an intrarectal balloon for the initial 15 of 40 treatments. Planning treatment volume dose was 72 Gy (95% normalization). A Mantel-Haenzel Chi-square test compared the distribution of GU, GI, and D symptoms at baseline and at end of treatment (EOT). Results: There was no significant difference between the 2 time points in the proportion of patients with bowel symptoms (p = 0.73), tenesmus (p = 0.27), nocturia (p = 1.00), or GU urgency (p = 0.40). However, there was a significant decrease in GU frequency (70% vs. 50%, p = 0.46) as a result of medical interventions and a significant increase in hemorrhoidal irritation (4% vs. 20%, p = 0.02) and anal cutaneous skin reaction (0% vs. 70%, p < 0.001). By 3 months after EOT compared to baseline, there was no significant difference in the proportion of patients experiencing hemorrhoidal bleeding (4% vs. 8%, p = 0.52), requiring intervention for hemorrhoidal symptoms (7% vs. 5%, p = 0.8), or experiencing persistent anal cutaneous skin reaction (0% vs. 3%, p = 0.31). Conclusion: Dose-escalated 3DCRT using an intrarectal balloon for prostate localization and immobilization was well tolerated. Acute GU, GI, and D symptoms resolved with standard dietary or medical interventions by the EOT or shortly thereafter

Class solution to decrease rectal dose in prostate radiotherapy treatments 3D-CRT; Solucion de clase para disminuir dosis en recto en tratamientos de prostata con radioterapia 3D-CRT

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Andres Rodriguez, C.; Tortosa Oliver, R.; Alonso Hernandez, D.; Mari Palacios, A.; Castillo Belmonte, A. del

2011-07-01

This paper contains a method developed in our center with conventional 3D radiotherapy techniques to increase the dose conformation around the target volume in prostate cancer treatments significantly reduced the doses to the rectum. To evaluate the goodness of the method, the results are compared with two classical techniques of treatment.

Dosimetric comparison between CT and X-ray simulation of radiotherapy for lung cancer

International Nuclear Information System (INIS)

Kali Ayguli, Zhang Jinrong; Wang Juwu; Ge Feng; Wang Haifeng; Xu Suling

2007-01-01

Objective: To compare radiotherapy plan of conventional X-ray simulation with CT simulation by 3D-TPS for lung cancer. Methods: Thirty-three patients were allotted to receive both conventional X-ray simulation and CT simulation in the same treatment position. 3D-TPS was used to design 4-field conventional plan of X-ray simulation (RT), 4-field two dimensional plan(2D)and three dimensional conformal radiation plan(3DCRT) of CT simulation for all patients. The total dose was 50 Gy. Dose volume histogram(DVH) was applied to evaluate the difference of target coverage, dose distribution and normal tissue protection among the three plans. Results: 3DCRT and 2D based on CT simulation were superior to RT in the target coverage, target conformity index (TCI) and target homogeneity (TH) (P 20 , V 30 and mean lung dose were similar among 3DCRT, 2D and RT plans. Moreover, the maximum doses of spinal cord were significantly different among the three plans. No statistical differences of doses to 30% of the heart and esophagus volume among the three plans were observed. Conclusions: There is significantly better tumour volume coverage in CT simulation when compared with X-ray conventional simulation. Target volume delineation by CT simulation is improved significantly. The dose distribution is improved by using three dimensional treatment planning system. 3DCRT plan is superior to 2D plans in target conformity index and target homogeneity. Doses delivered to organs surrounding the target such as lung and heart were reduced significantly in 3DCRT. (authors)

Physics aspects of recent and future concepts in radiotherapy

International Nuclear Information System (INIS)

Georg, D.

2001-01-01

Full text: The development of 3-D conformal radiotherapy (3D-CRT), in which the high dose volume matches as closely as possible the target volume and avoids therefore normal tissue irradiation as far as possible, has been a major theme in radiotherapy for improving the therapeutic window. Conformal radiotherapy is not a new concept but only the technological improvements of the last decade allow its clinical implementation. More recent and advanced forms of 3D-CRT are intensity modulated radiotherapy (IMRT) and stereotactic radiotherapy (SRT). IMRT uses an additional degree of freedom to achieve a new class of conformation: the variation of the primary beam intensity. SRT is based on a three dimensional stereotactic coordinate system which is correlated with the patient and the treatment facility through modern imaging technology. IMRT and SRT are related by common features, e.g. high dose gradients and small fields which require a high geometric precision. A high dosimetric and geometric precision can only be based on a detailed knowledge of the patient specific anatomy. Therefore, IMRT and SRT need to underlie multi-modality imaging studies. Both IMRT and SRT utilize photon beams and multiple field arrangements which increase the volumes of healthy tissue receiving low doses. Photons have a low selectivity along the beam direction implying that the sharp dose gradients are to be compromised. The increased low dose volume as well as the low selectivity of photon beams can be over-come by using proton or ions. Brachytherapy, a form of radiotherapy where encapsuled radioactive sources are placed directly in or in the vicinity of the tumor, is by definition conformal. Endovascular brachytherapy has become a promising new field in radiotherapy for the prevention of (re)stenosis after angioplasty. Although many clinical trials have been performed during the last years specific aspects related to endovascular brachytherapy have not been addressed clearly, such as the

Radiotherapy of intensity modulated VS conformational in the treatment of carcinoma of the prostate. A dosimetric comparison; Radioterapia de intensidad modulada VS conformacional en el tratamiento de carcinoma de prostata. Una camparacion dosimetrica

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Rodriguez Martin, G.; Garcia Vicente, F.; Zapatero Laborda, A.; Bermudez Luna, R.; Roch Gonzalez, M.; Perez Gonzalez, L.; Torres Escobar, J. J.

2013-07-01

The intensity modulated (IMRT) radiation therapy is a technique of high conformation which, by its nature, has as one of its main directions prostate cancer radiotherapy treatment. The purpose of this work is presents results of the dosimetric indicators collected in our hospital a number of patients of carcinoma of the prostate with standard three-dimensional Conformal technique (3D-CRT) and IMRT. Aims to demonstrate and quantify with a statistical methodology that, establishing an adequate Protocol of IMRT, significant reductions in risk organ doses can be obtained by keeping the same prescription to the white volume. (Author)

A Dosimetric Comparison of Accelerated Partial Breast Irradiation Techniques: Multicatheter Interstitial Brachytherapy, Three-Dimensional Conformal Radiotherapy, and Supine Versus Prone Helical Tomotherapy

International Nuclear Information System (INIS)

Patel, Rakesh R.; Becker, Stewart J.; Das, Rupak K.; Mackie, Thomas R.

2007-01-01

Purpose: To compare dosimetrically four different techniques of accelerated partial breast irradiation (APBI) in the same patient. Methods and Materials: Thirteen post-lumpectomy interstitial brachytherapy (IB) patients underwent imaging with preimplant computed tomography (CT) in the prone and supine position. These CT scans were then used to generate three-dimensional conformal radiotherapy (3D-CRT) and prone and supine helical tomotherapy (PT and ST, respectively) APBI plans and compared with the treated IB plans. Dose-volume histogram analysis and the mean dose (NTD mean ) values were compared. Results: Planning target volume coverage was excellent for all methods. Statistical significance was considered to be a p value mean dose of 1.3 Gy 3 and 1.2 Gy 3 , respectively. Both of these methods were statistically significantly lower than the supine external beam techniques. Overall, all four methods yielded similar low doses to the heart. Conclusions: The use of IB and PT resulted in greater normal tissue sparing (especially ipsilateral breast and lung) than the use of supine external beam techniques of 3D-CRT or ST. However, the choice of APBI technique must be tailored to the patient's anatomy, lumpectomy cavity location, and overall treatment goals

Three-dimensional conformal external beam radiotherapy compared with permanent prostate implantation in low-risk prostate cancer based on endorectal magnetic resonance spectroscopy imaging and prostate-specific antigen level

International Nuclear Information System (INIS)

Pickett, Barby; Kurhanewicz, John; Pouliot, Jean; Weinberg, Vivian; Shinohara, Katsuto; Coakley, Fergus; Roach, Mack

2006-01-01

Purpose: To evaluate the metabolic response by comparing the time to resolution of spectroscopic abnormalities (TRSA) and the time to prostate-specific antigen level in low-risk prostate cancer patients after treatment with three-dimensional conformal external beam radiotherapy (3D-CRT) compared with permanent prostate implantation (PPI). Recent studies have suggested that the treatment of low-risk prostate cancer yields similar results for patients treated with 3D-CRT or PPI. Methods and Materials: A total of 50 patients, 25 in each group, who had been treated with 3D-CRT or PPI, had undergone endorectal magnetic resonance spectroscopy imaging before and/or at varying times after therapy. The 3D-CRT patients had received radiation doses of ≥72 Gy compared with 144 Gy for the PPI patients. The spectra from all usable voxels were examined for detectable levels of metabolic signal, and the percentages of atrophic and cancerous voxels were tabulated. Results: The median time to resolution of the spectroscopic abnormalities was 32.2 and 24.8 months and the time to the nadir prostate-specific antigen level was 52.4 and 38.0 months for the 3D-CRT and PPI patients, respectively. Of the 3D-CRT patients, 92% achieved negative endorectal magnetic resonance spectroscopy imaging findings, with 40% having complete metabolic atrophy. All 25 PPI patients had negative endorectal magnetic resonance spectroscopy imaging findings, with 60% achieving complete metabolic atrophy. Conclusion: The results of this study suggest that metabolic and biochemical responses of the prostate are more pronounced after PPI. Our results have not proved PPI is more effective at curing prostate cancer, but they have demonstrated that it may be more effective at destroying prostate metabolism

Evaluation on prognosis of esophageal squamous cell carcinoma patients after three-dimensional conformal radiotherapy with different clinical stage system

International Nuclear Information System (INIS)

Wang Yuxiang; Zhu Shuchai; Qiu Rong; Liu Zhikun; Shen Wenbin

2011-01-01

Objective: To evaluate the prognostic significance of 3 clinical stage system in 3-dimensional conformal radiotherapy (3DCRT) for esophageal squamous cell carcinoma. Methods: From January 2004 to August 2007, 179 cases of esophageal squamous cell carcinoma were treated with 3DCRT. Before radiation, each patient was staged with UICC 2003 TNM stage, stage of Chinese esophageal cancer cooperation group (cooperation group' stage), and Zhu's clinical stage respectively. Concordance of each clinical stage and prognosis was analyzed with SPSS 11.5. Results In 179 cases of esophageal cancer, Concordance was better in T stage (Kappa = 0.271) than in TNM stage (Kappa = 0.167) between cooperation group' stage and Zhu's stage. Among them, 98 cases was staged with UICC stage, concordance of T stage was better between UICC-T and cooperation group' T stage (Kappa =0.261) than between UICCT and Zhu's T stage (Kappa = 0.045) ;concordance of TNM stage was better between UICC-TNM and Zhu's TNM stage (Kappa = 0.597) than between UICC-TNM and cooperation group' TNM stage (Kappa =0.299). With multivariate analysis, T (χ 2 value is 11.58, 26.00 and 51.05, all P 2 value is 15.28, 16.10 and 16.10, all P 2 value is 5.59, 27.78 and 27.78, all P 2 value is 15.77, 34, 35 and 51.10, all P 1 - T 3 was difficult to definite and the prognosis was not significantly different in T 1 - T 3 stage. Conclusions: In this study, 3 kinds of clinical stage could evaluate prognosis of esophageal cancer after radiotherapy; cooperation group' stage and Zhu's stage need further application, with further accuracy needed. (authors)

A dosimetric comparison of 3D-CRT, IMRT, and static tomotherapy with an SIB for large and small breast volumes

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Michalski, Andrea [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Central Coast Cancer Centre, Gosford Hospital, Gosford, New South Wales (Australia); Atyeo, John, E-mail: john.atyeo@sydney.edu.au [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Cox, Jennifer [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Department of Radiation Oncology, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Rinks, Marianne [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Radiation Oncology, Cancer Services, Illawarra Shoalhaven Local Health District, Wollongong, New South Wales (Australia); Morgia, Marita; Lamoury, Gillian [Department of Radiation Oncology, Royal North Shore Hospital, St Leonards, New South Wales (Australia)

2014-07-01

Radiation therapy to the breast is a complex task, with many different techniques that can be employed to ensure adequate dose target coverage while minimizing doses to the organs at risk. This study compares the dose planning outcomes of 3 radiation treatment modalities, 3 dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and static tomotherapy, for left-sided whole-breast radiation treatment with a simultaneous integrated boost (SIB). Overall, 20 patients with left-sided breast cancer were separated into 2 cohorts, small and large, based on breast volume. Dose plans were produced for each patient using 3D-CRT, IMRT, and static tomotherapy. All patients were prescribed a dose of 45 Gy in 20 fractions to the breast with an SIB of 56 Gy in 20 fractions to the tumor bed and normalized so that D{sub 98%} > 95% of the prescription dose. Dosimetric comparisons were made between the 3 modalities and the interaction of patient size. All 3 modalities offered adequate planning target volume (PTV) coverage with D{sub 98%} > 95% and D{sub 2%} < 107%. Static tomotherapy offered significantly improved (p = 0.006) dose homogeneity to the PTV{sub boost} {sub eval} (0.079 ± 0.011) and breast minus the SIB volume (Breast{sub SIB}) (p < 0.001, 0.15 ± 0.03) compared with the PTV{sub boost} {sub eval} (0.085 ± 0.008, 0.088 ± 0.12) and Breast{sub SIB} (0.22 ± 0.05, 0.23 ± 0.03) for IMRT and 3D-CRT, respectively. Static tomotherapy also offered statistically significant reductions (p < 0.001) in doses to the ipsilateral lung mean dose of 6.79 ± 2.11 Gy compared with 7.75 ± 2.54 Gy and 8.29 ± 2.76 Gy for IMRT and 3D-CRT, respectively, and significantly (p < 0.001) reduced heart doses (mean = 2.83 ± 1.26 Gy) compared to both IMRT and 3D-CRT (mean = 3.70 ± 1.44 Gy and 3.91 ± 1.58 Gy). Static tomotherapy is the dosimetrically superior modality for the whole breast with an SIB compared with IMRT and 3D-CRT. IMRT is superior to 3D-CRT

Sonographic Assessment of Parotid and Submandibular Glands in Patients Undergoing 3D Conformal Radiotherapy

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Johari M

2016-06-01

Full Text Available The aim of this study was to evaluate sonographic changes in parotid and submandibular salivary glands in patients undergoing radiotherapy for head and neck malignancies. In addition, salivary changes subsequent to radiotherapy were evaluated objectively and subjectively. Twenty patients(13males and 7females with head and neck malignancies, who had been referred to the Radiotherapy/Oncology Department of the Shahid Madani Hospital in Tabriz, Iran, were included in the study. Length, width, echotexture, echogenicity and margins of parotid and submandibular glands were evaluated before and after radiotherapy using sonography. Peak-systolic velocity(PSV,end-diastolic velocity(EDV and resistive index(RI were also assessed by Doppler sonography. Xerostomia subsequent to radiotherapy was evaluated with the use of two techniques: patients’ self-reported scoring and objective measurement of resting saliva. There was a significant decrease in the width of the parotid gland after radiotherapy compared to baseline(P=0.005.Although the length of the parotid gland and the dimensions of submandibular gland decrease, the differences were not significant. In addition, the echogenicity, echotexture and the margin of the glands change to hypoechoic, heterogenic and irregular, respectively, subsequent to radiotherapy. The Doppler technique showed decrease in PSV and RI and an increase in EDV; however, only the decrease in RI in the submandibular gland was statistically significant(P=0.002.The results showed a significant decrease in salivary flow after radiotherapy(P<0.001.In addition, based on the patients reports, the severity of xerostomia increased significantly after radiotherapy(P<0.001. Songraphic changes of parotid and submandibular glands after radiotherapy should be considered in ultrasound examinations. The damages to the parotid and submandibular glands had significant influence in patient post 3D-CRT.

Sucralfate versus mesalazine versus hydrocortisone in the prevention of acute radiation proctitis during conformal radiotherapy for prostate carcinoma. A randomized study

International Nuclear Information System (INIS)

Sanguineti, G.; Franzone, P.; Marcenaro, M.; Vitale, V.; Foppiano, F.

2003-01-01

Purpose: To assess whether the topical use of steroids or 5-aminosalicylic acid (5-ASA) is superior to sucralfate in preventing acute rectal toxicity during three-dimensional conformal radiotherapy (3DCRT) to 76 Gy. Patients and Methods: Patients undergoing 3DCRT for prostate carcinoma at our institution were offered to be randomized to sucralfate 3 g in 15 ml suspension enema (Antepsin trademark ), mesalazine 4 g gel enema (Enterasyn trademark), or hydrocortisone 100 mg foam enema (Colifoam trademark ). Randomization was blind to the treating physician but not to the patient. Sucralfate was chosen as control arm. Topical treatment had to be performed once daily, starting on day 1 of 3DCRT. Acute rectal toxicity was scored weekly according to RTOG criteria. Time to occurrence of grade 2+ acute rectal toxicity was taken as endpoint. Results: The trial was opened in August 1999, and after the first 24 patients had been treated, arm 2 was discontinued because of eight patients receiving mesalazine, seven actually developed acute rectal toxicity (five patients grade 3 and two patients grade 2). Until May 2001, 134 consecutive patients were randomly assigned to sucralfate (63 patients), mesalazine (eight patients) or hydrocortisone (63 patients). The cumulative incidence of acute rectal toxicity at the end of treatment by arm is 61.9 ± 6.1%, 87.5 ± 11.7%, and 52.4 ± 6.2% for arms 1, 2, and 3, respectively. The difference between the mesalazine group and the sucralfate group is highly significant (hazard ratio [HR] 2.5, 95% confidence interval [CI] 1.1-5.7; p = 0.03). At both uni- and multivariate analysis taking into account several patients and treatment covariates, the difference between hydrocortisone and sucralfate is not significant (HR 0.7, 95% CI 0.5-1.2; p = 0.2). Conclusion: Topical mesalazine is contraindicated during radiotherapy. Hydrocortisone enema is not superior to sucralfate in preventing acute rectal toxicity. (orig.)

Sucralfate versus mesalazine versus hydrocortisone in the prevention of acute radiation proctitis during conformal radiotherapy for prostate carcinoma. A randomized study

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Sanguineti, G.; Franzone, P.; Marcenaro, M.; Vitale, V. [Dept. of Radiation Oncology, National Inst. for Cancer Research, Genova (Italy); Foppiano, F. [Dept. of Physics, National Inst. for Cancer Research, Genova (Italy)

2003-07-01

Purpose: To assess whether the topical use of steroids or 5-aminosalicylic acid (5-ASA) is superior to sucralfate in preventing acute rectal toxicity during three-dimensional conformal radiotherapy (3DCRT) to 76 Gy. Patients and Methods: Patients undergoing 3DCRT for prostate carcinoma at our institution were offered to be randomized to sucralfate 3 g in 15 ml suspension enema (Antepsin {sup trademark}), mesalazine 4 g gel enema (Enterasyn trademark), or hydrocortisone 100 mg foam enema (Colifoam {sup trademark}). Randomization was blind to the treating physician but not to the patient. Sucralfate was chosen as control arm. Topical treatment had to be performed once daily, starting on day 1 of 3DCRT. Acute rectal toxicity was scored weekly according to RTOG criteria. Time to occurrence of grade 2+ acute rectal toxicity was taken as endpoint. Results: The trial was opened in August 1999, and after the first 24 patients had been treated, arm 2 was discontinued because of eight patients receiving mesalazine, seven actually developed acute rectal toxicity (five patients grade 3 and two patients grade 2). Until May 2001, 134 consecutive patients were randomly assigned to sucralfate (63 patients), mesalazine (eight patients) or hydrocortisone (63 patients). The cumulative incidence of acute rectal toxicity at the end of treatment by arm is 61.9 {+-} 6.1%, 87.5 {+-} 11.7%, and 52.4 {+-} 6.2% for arms 1, 2, and 3, respectively. The difference between the mesalazine group and the sucralfate group is highly significant (hazard ratio [HR] 2.5, 95% confidence interval [CI] 1.1-5.7; p = 0.03). At both uni- and multivariate analysis taking into account several patients and treatment covariates, the difference between hydrocortisone and sucralfate is not significant (HR 0.7, 95% CI 0.5-1.2; p = 0.2). Conclusion: Topical mesalazine is contraindicated during radiotherapy. Hydrocortisone enema is not superior to sucralfate in preventing acute rectal toxicity. (orig.)

Conformal Radiotherapy: Physics, Treatment Planning and Verification. Proceedings book

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De Wagter, C [ed.

1995-12-01

The goal of conformal radiotherapy is to establish radiation dose distributions that conform tightly to the target volume in view of limiting radiation to normal tissues. Conformal radiotherapy significantly improves both local control and palliation and thus contributes to increase survival and to improve the quality of life. The subjects covered by the symposium include : (1) conformal radiotherapy and multi-leaf collimation; (2) three dimensional imaging; (3) treatment simulation, planning and optimization; (4) quality assurance; and (5) dosimetry. The book of proceedings contains the abstracts of the invited lectures, papers and poster presentations as well as the full papers of these contributions.

Conformal Radiotherapy: Physics, Treatment Planning and Verification. Proceedings book

International Nuclear Information System (INIS)

De Wagter, C.

1995-12-01

The goal of conformal radiotherapy is to establish radiation dose distributions that conform tightly to the target volume in view of limiting radiation to normal tissues. Conformal radiotherapy significantly improves both local control and palliation and thus contributes to increase survival and to improve the quality of life. The subjects covered by the symposium include : (1) conformal radiotherapy and multi-leaf collimation; (2) three dimensional imaging; (3) treatment simulation, planning and optimization; (4) quality assurance; and (5) dosimetry. The book of proceedings contains the abstracts of the invited lectures, papers and poster presentations as well as the full papers of these contributions

Design and implementation of a rotational radiotherapy technique for breast cancer treatment and their comparison with 3-D-Crt irradiation technique; Diseno e implementacion de una tecnica de radioterapia rotacional para tratamiento de cancer de mama y su comparacion contra la tecnica 3D-CRT de irradiacion

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Gutierrez M, J. G.; Lopez V, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Velazquez T, J. J.; Adame G, C. S. [Centro Medico Nacional Siglo XXI, Hospital de Oncologia, Departamento de Fisica Medica, Av. Cuauhtemoc No. 330, Col. Doctores, 06720 Mexico D. F. (Mexico); Rubio N, O.; Chagoya G, A.; Hernandez G, J. C., E-mail: jggm25@yahoo.com.mx [Centro Medico Nacional Siglo XXI, Hospital de Oncologia, Departamento de Radioterapia, Av. Cuauhtemoc No. 330, Col. Doctores, 06720 Mexico D. F. (Mexico)

2015-10-15

Breast cancer is one of oncological diseases worldwide, as well in Mexico, which causes even more deaths than cervical cancer; this condition is the second death cause in women aged 30-54 years and threatens all socio-economic groups. The treatment is highly dependent on the stage which is detected and based on protocols that include a combination of surgery, chemotherapy and radiotherapy. This paper studies the main irradiation technique for patients with mastectomy, breast full cycle (irradiation of the chest well and supraclavicular nodes) in their mode Three Dimensional - Conformal Radiation Therapy (3-D-Crt), and compared with the Volumetric Modulated Arc Therapy (VMAT) technique proposed in this paper. In both techniques the prescription was 50 Gy divided into 25 fractions. The techniques were applied in three female patients (being an initial study) with disease of the left side, the target volume and organs at risk were delineated by the medical treating radiation oncologist, the planning system used was Eclipse version 10; for quantitative comparison of both plans indexes of homogeneity were used, con formality, the target volume coverage and normal tissue, sub factors and overdosing, the conformation number and coverage quality. They were evaluated and compared the media, maximum and minimum dose of the organs at risk, based on the fact that the coverage of the target volume, dose gradient and dose at risk organs are acceptable (prescription dose greater that 90% coverage, gradient less that 20% and organs at risk in accordance with the Quantec limitations for both versions). (Author)

Dosimetric Study of Current Treatment Options for Radiotherapy in Retinoblastoma

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Eldebawy, Eman [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Department of Radiation Oncology, Children' s Cancer Hospital, Cairo (Egypt); Parker, William, E-mail: william.parker@mcgill.ca [Department of Medical Physics, McGill University Health Centre, Montreal, Quebec (Canada); Abdel Rahman, Wamied [Department of Medical Physics, McGill University Health Centre, Montreal, Quebec (Canada); Freeman, Carolyn R. [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada)

2012-03-01

Purpose: To determine the best treatment technique for patients with retinoblastoma requiring radiotherapy to the whole eye. Methods and Materials: Treatment plans for 3 patients with retinoblastoma were developed using 10 radiotherapy techniques including electron beams, photon beam wedge pair (WP), photon beam three-dimensional conformal radiotherapy (3D-CRT), fixed gantry intensity-modulated radiotherapy (IMRT), photon volumetric arc therapy (VMAT), fractionated stereotactic radiotherapy, and helical tomotherapy (HT). Dose-volume analyses were carried out for each technique. Results: All techniques provided similar target coverage; conformity was highest for VMAT, nine-field (9F) IMRT, and HT (conformity index [CI] = 1.3) and lowest for the WP and two electron techniques (CI = 1.8). The electron techniques had the highest planning target volume dose gradient (131% of maximum dose received [D{sub max}]), and the CRT techniques had the lowest (103% D{sub max}) gradient. The volume receiving at least 20 Gy (V{sub 20Gy}) for the ipsilateral bony orbit was lowest for the VMAT and HT techniques (56%) and highest for the CRT techniques (90%). Generally, the electron beam techniques were superior in terms of brain sparing and delivered approximately one-third of the integral dose of the photon techniques. Conclusions: Inverse planned image-guided radiotherapy delivered using HT or VMAT gives better conformity index, improved orbital bone and brain sparing, and a lower integral dose than other techniques.

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.

Significant reduction of normal tissue dose by proton radiotherapy compared with three-dimensional conformal or intensity-modulated radiation therapy in Stage I or Stage III non-small-cell lung cancer

International Nuclear Information System (INIS)

Chang, Joe Y.; Zhang Xiaodong; Wang Xiaochun; Kang Yixiu; Riley, Beverly C.; Bilton, Stephen C.; Mohan, Radhe; Komaki, Ritsuko; Cox, James D.

2006-01-01

Purpose: To compare dose-volume histograms (DVH) in patients with non-small-cell lung cancer (NSCLC) treated by photon or proton radiotherapy. Methods and Materials: Dose-volume histograms were compared between photon, including three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and proton plans at doses of 66 Gy, 87.5 Gy in Stage I (n = 10) and 60-63 Gy, and 74 Gy in Stage III (n 15). Results: For Stage I, the mean total lung V5, V10, and V20 were 31.8%, 24.6%, and 15.8%, respectively, for photon 3D-CRT with 66 Gy, whereas they were 13.4%, 12.3%, and 10.9%, respectively, with proton with dose escalation to 87.5 cobalt Gray equivalents (CGE) (p = 0.002). For Stage III, the mean total lung V5, V10, and V20 were 54.1%, 46.9%, and 34.8%, respectively, for photon 3D-CRT with 63 Gy, whereas they were 39.7%, 36.6%, and 31.6%, respectively, for proton with dose escalation to 74 CGE (p = 0.002). In all cases, the doses to lung, spinal cord, heart, esophagus, and integral dose were lower with proton therapy even compared with IMRT. Conclusions: Proton treatment appears to reduce dose to normal tissues significantly, even with dose escalation, compared with standard-dose photon therapy, either 3D-CRT or IMRT

Radiation-induced esophagitis in local advanced non-small cell lung cancer after three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Tian Dandan; Wang Yuxiang; Qiu Rong; Zhu Shuchai; Tian Xiuming; Qiao Xueying

2014-01-01

Objective: To explore radiation-induced esophagitis and its related factors in the patients with local advanced non-small cell lung cancer (NSCLC) which were treated with three-dimensional conformal radiation therapy (3D-CRT). Methods: From January 2001 to December 2008, 203 patients who suffered from stage Ⅲ NSCLC were achieved, including 163 males and 40 females, with a median age of 63 years old, while 79 cases were in stage Ⅲ_a and 124 in stage Ⅲ_b. The equivalent median dose of tumor was 62 Gy(range of 50-78 Gy). Among them, 74 cases were administered with radiotherapy alone, 45 with sequential radiotherapy and chemotherapy, 87 cases with concurrent radiochemotherapy. Radiation esophagitis was evaluated with RTOG standard. The dosimetric parameters was estimated from dose volume histogrma (DVH). The clinical and dosimetric parameters of radiation esophagitis were evaluated by spearman correlatived univariate and Logistic multivariable analysis.Results After radiotherapy, out of 203 patients, 87 had acute radiation esophagitis(RE), 47 in grade 1, 37 in grade 2, and 3 in grade 3 RE. According to spearman correlatived analysis, the correlatived factors included ages, chemotherapy, GTV, PTV, the mean doses of PTV and lung, the max and mean dose of esophagus, V_4_0, V_4_5, V_5_0, V_5_5, V_6_0, length of esophagus (total circumference) treated with 45 Gy (LETT_4_5), and LETT_5_0 (r = -0.162-0.235, P 0.05). There were 21 factors, such as gender, age, smoking, clinical stage, site of tumor, chemotherapy, GTV, PTV, mean dose of PTV and lung, max and mean dose of esophagus, V_4_0-V_6_0 of esophagus, LETT_4_5_-_6_0, incorporated into multivariable analysis, only chemotherapy and V_4_5 of esophagus were independent predicted factors(Wald = 4.626, 9.882, P < 0.05). Conclusions: In local advanced NSCLC after 3D-CRT, chemotherapy(especially concurrent radiochemotherapy) could increase radiation-induced esophagitis. The parameter of DVH could also be used to predict

Comparison of rectal volume definition techniques and their influence on rectal toxicity in patients with prostate cancer treated with 3D conformal radiotherapy: a dose-volume analysis

International Nuclear Information System (INIS)

Onal, Cem; Topkan, Erkan; Efe, Esma; Yavuz, Melek; Sonmez, Serhat; Yavuz, Aydin

2009-01-01

To evaluate the impact of four different rectum contouring techniques and rectal toxicities in patients with treated with 3D conformal radiotherapy (3DCRT). Clinical and dosimetric data were evaluated for 94 patients who received a total dose 3DCRT of 70 Gy, and rectal doses were compared in four different rectal contouring techniques: the prostate-containing CT sections (method 1); 1 cm above and below the planning target volume (PTV) (method 2); 110 mm starting from the anal verge (method 3); and from the anal verge to the sigmoid flexure (method 4). The percentage of rectal volume receiving RT doses (30–70 Gy) and minimum, mean rectal doses were assessed. Median age was 69 years. Percentage of rectal volume receiving high doses (≥ 70 Gy) were higher with the techniques that contoured smaller rectal volumes. In methods 2 and 3, the percentage of rectal volume receiving ≥ 70 Gy was significantly higher in patients with than without rectal bleeding (method 2: 30.8% vs. 22.5%, respectively (p = 0.03); method 3: 26.9% vs. 18.1%, respectively (p = 0.006)). Mean rectal dose was significant predictor of rectal bleeding only in method 3 (48.8 Gy in patients with bleeding vs. 44.4 Gy in patients without bleeding; p = 0.02). Different techniques of rectal contouring significantly influence the calculation of radiation doses to the rectum and the prediction of rectal toxicity. Rectal volume receiving higher doses (≥ 70 Gy) and mean rectal doses may significantly predict rectal bleeding for techniques contouring larger rectal volumes, as was in method 3

Pulmonary Toxicity in Stage III Non-Small Cell Lung Cancer Patients Treated With High-Dose (74 Gy) 3-Dimensional Conformal Thoracic Radiotherapy and Concurrent Chemotherapy Following Induction Chemotherapy: A Secondary Analysis of Cancer and Leukemia Group B (CALGB) Trial 30105

International Nuclear Information System (INIS)

Salama, Joseph K.; Stinchcombe, Thomas E.; Gu Lin; Wang Xiaofei; Morano, Karen; Bogart, Jeffrey A.; Crawford, Jeffrey C.; Socinski, Mark A.; Blackstock, A. William; Vokes, Everett E.

2011-01-01

Purpose: Cancer and Leukemia Group B (CALGB) 30105 tested two different concurrent chemoradiotherapy platforms with high-dose (74 Gy) three-dimensional conformal radiotherapy (3D-CRT) after two cycles of induction chemotherapy for Stage IIIA/IIIB non–small cell lung cancer (NSCLC) patients to determine if either could achieve a primary endpoint of >18-month median survival. Final results of 30105 demonstrated that induction carboplatin and gemcitabine and concurrent gemcitabine 3D-CRT was not feasible because of treatment-related toxicity. However, induction and concurrent carboplatin/paclitaxel with 74 Gy 3D-CRT had a median survival of 24 months, and is the basis for the experimental arm in CALGB 30610/RTOG 0617/N0628. We conducted a secondary analysis of all patients to determine predictors of treatment-related pulmonary toxicity. Methods and Materials: Patient, tumor, and treatment-related variables were analyzed to determine their relation with treatment-related pulmonary toxicity. Results: Older age, higher N stage, larger planning target volume (PTV)1, smaller total lung volume/PTV1 ratio, larger V20, and larger mean lung dose were associated with increasing pulmonary toxicity on univariate analysis. Multivariate analysis confirmed that V20 and nodal stage as well as treatment with concurrent gemcitabine were associated with treatment-related toxicity. A high-risk group comprising patients with N3 disease and V20 >38% was associated with 80% of Grades 3-5 pulmonary toxicity cases. Conclusions: Elevated V20 and N3 disease status are important predictors of treatment related pulmonary toxicity in patients treated with high-dose 3D-CRT and concurrent chemotherapy. Further studies may use these metrics in considering patients for these treatments.

Pulmonary Toxicity in Stage III Non-Small Cell Lung Cancer Patients Treated With High-Dose (74 Gy) 3-Dimensional Conformal Thoracic Radiotherapy and Concurrent Chemotherapy Following Induction Chemotherapy: A Secondary Analysis of Cancer and Leukemia Group B (CALGB) Trial 30105

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Salama, Joseph K., E-mail: joseph.salama@duke.edu [Duke University Medical Center, Durham, NC (United States); Stinchcombe, Thomas E. [University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Gu Lin; Wang Xiaofei [CALGB Statistical Center, Duke University Medical Center, Durham, NC (United States); Morano, Karen [Quality Assurance Review Center, Lincoln, RI (United States); Bogart, Jeffrey A. [State University of New York Upstate Medical University, Syracuse, NY (United States); Crawford, Jeffrey C. [Duke University Medical Center, Durham, NC (United States); Socinski, Mark A. [University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Blackstock, A. William [Wake Forest University School of Medicine, Winston-Salem, NC (United States); Vokes, Everett E. [University of Chicago, Chicago, IL (United States)

2011-11-15

Purpose: Cancer and Leukemia Group B (CALGB) 30105 tested two different concurrent chemoradiotherapy platforms with high-dose (74 Gy) three-dimensional conformal radiotherapy (3D-CRT) after two cycles of induction chemotherapy for Stage IIIA/IIIB non-small cell lung cancer (NSCLC) patients to determine if either could achieve a primary endpoint of >18-month median survival. Final results of 30105 demonstrated that induction carboplatin and gemcitabine and concurrent gemcitabine 3D-CRT was not feasible because of treatment-related toxicity. However, induction and concurrent carboplatin/paclitaxel with 74 Gy 3D-CRT had a median survival of 24 months, and is the basis for the experimental arm in CALGB 30610/RTOG 0617/N0628. We conducted a secondary analysis of all patients to determine predictors of treatment-related pulmonary toxicity. Methods and Materials: Patient, tumor, and treatment-related variables were analyzed to determine their relation with treatment-related pulmonary toxicity. Results: Older age, higher N stage, larger planning target volume (PTV)1, smaller total lung volume/PTV1 ratio, larger V20, and larger mean lung dose were associated with increasing pulmonary toxicity on univariate analysis. Multivariate analysis confirmed that V20 and nodal stage as well as treatment with concurrent gemcitabine were associated with treatment-related toxicity. A high-risk group comprising patients with N3 disease and V20 >38% was associated with 80% of Grades 3-5 pulmonary toxicity cases. Conclusions: Elevated V20 and N3 disease status are important predictors of treatment related pulmonary toxicity in patients treated with high-dose 3D-CRT and concurrent chemotherapy. Further studies may use these metrics in considering patients for these treatments.

A high-precision system for conformal intracranial radiotherapy

International Nuclear Information System (INIS)

Tome, Wolfgang A.; Meeks, Sanford L.; Buatti, John M.; Bova, Francis J.; Friedman, William A.; Li Zuofeng

2000-01-01

Purpose: Currently, optimally precise delivery of intracranial radiotherapy is possible with stereotactic radiosurgery and fractionated stereotactic radiotherapy. We report on an optimally precise optically guided system for three-dimensional (3D) conformal radiotherapy using multiple noncoplanar fixed fields. Methods and Materials: The optically guided system detects infrared light emitting diodes (IRLEDs) attached to a custom bite plate linked to the patient's maxillary dentition. The IRLEDs are monitored by a commercially available stereo camera system, which is interfaced to a personal computer. An IRLED reference is established with the patient at the selected stereotactic isocenter, and the computer reports the patient's current position based on the location of the IRLEDs relative to this reference position. Using this readout from the computer, the patient may be dialed directly to the desired position in stereotactic space. The patient is localized on the first day and a reference file is established for 5 different couch positions. The patient's image data are then imported into a commercial convolution-based 3D radiotherapy planning system. The previously established isocenter and couch positions are then used as a template upon which to design a conformal 3D plan with maximum beam separation. Results: The use of the optically guided system in conjunction with noncoplanar radiotherapy treatment planning using fixed fields allows the generation of highly conformal treatment plans that exhibit a high degree of dose homogeneity and a steep dose gradient. To date, this approach has been used to treat 28 patients. Conclusion: Because IRLED technology improves the accuracy of patient localization relative to the linac isocenter and allows real-time monitoring of patient position, one can choose treatment-field margins that only account for beam penumbra and image resolution without adding margin to account for larger and poorly defined setup uncertainty. This

Results of a multicentric in silico clinical trial (ROCOCO): comparing radiotherapy with photons and protons for non-small cell lung cancer.

Science.gov (United States)

Roelofs, Erik; Engelsman, Martijn; Rasch, Coen; Persoon, Lucas; Qamhiyeh, Sima; de Ruysscher, Dirk; Verhaegen, Frank; Pijls-Johannesma, Madelon; Lambin, Philippe

2012-01-01

This multicentric in silico trial compares photon and proton radiotherapy for non-small cell lung cancer patients. The hypothesis is that proton radiotherapy decreases the dose and the volume of irradiated normal tissues even when escalating to the maximum tolerable dose of one or more of the organs at risk (OAR). Twenty-five patients, stage IA-IIIB, were prospectively included. On 4D F18-labeled fluorodeoxyglucose-positron emission tomography-computed tomography scans, the gross tumor, clinical and planning target volumes, and OAR were delineated. Three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) photon and passive scattered conformal proton therapy (PSPT) plans were created to give 70 Gy to the tumor in 35 fractions. Dose (de-)escalation was performed by rescaling to the maximum tolerable dose. Protons resulted in the lowest dose to the OAR, while keeping the dose to the target at 70 Gy. The integral dose (ID) was higher for 3DCRT (59%) and IMRT (43%) than for PSPT. The mean lung dose reduced from 18.9 Gy for 3DCRT and 16.4 Gy for IMRT to 13.5 Gy for PSPT. For 10 patients, escalation to 87 Gy was possible for all 3 modalities. The mean lung dose and ID were 40 and 65% higher for photons than for protons, respectively. The treatment planning results of the Radiation Oncology Collaborative Comparison trial show a reduction of ID and the dose to the OAR when treating with protons instead of photons, even with dose escalation. This shows that PSPT is able to give a high tumor dose, while keeping the OAR dose lower than with the photon modalities.

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.

Three-dimensional conformal radiotherapy by delineations on CT-based simulation in different respiratory phases for the treatment of senile patients with non-small cell lung cancer.

Science.gov (United States)

Wang, Weifeng; Yuan, Feng; Wang, Guoping; Lin, Zhiren; Pan, Yanling; Chen, Longhua

2015-01-01

This study aimed to evaluate the application of three-dimensional conformal radiotherapy (3D-CRT) for elderly patients with non-small cell lung cancer (NSCLC) based on computed tomography (CT) simulations in different respiratory phases. A total of 64 patients aged >70 years old with NSCLC were treated by 3D-CRT using CT images in different respiratory phases. The gross tumor volumes (GTVs) at the end of inspiration and end of expiration were combined to obtain the total GTV, which was close to the motional range of tumors during respiration, and no additional expansion of the clinical target volume (CTAV) to planning target volume (PTV) (CTAV:PTV) was included during the recording of respiratory movements. Patients were also planned according to the classic 3D-CRT approach. Efficacy, prognostic factors, and side effects were evaluated. Compared with the classic approach, the average PTV was 18.9% lower (median: 17.3%), and the average lung volume receiving a prescribed dose for a tumor was 22.4% lower (median: 20.9%). The 1-, 2-, and 3-year survival rates were 70.6%, 54.9%, and 29.4%, respectively, with an overall tumor response rate of 79.7%. The Karnofsky performance status and N stage were independent prognostic factors, whereas age was not. Without affecting therapeutic effects, CT simulations in different respiratory phases were well-tolerated in elderly patients with NSCLC, could effectively reduce PTV, and could improve the quality of life.

Prediction of PET/CT to alleviate radiation pneumonitis in patients with non-small cell lung cancer for 3-dimentional conformal radiotherapy

International Nuclear Information System (INIS)

Gong Heyi; Yu Jinming; Li Jianbin; Li Baosheng; Fu Zheng; Liu Tonghai

2005-01-01

Objective: To investigate the impact of PET/CT on clinical staging of non-small cell lung cancer (NSCLC), delineation of target volume, and prediction to alleviate radiation pneumonitis (RP) from 3-dimentional conformal radiotherapy (3D-CRT) planning. Methods: From October 2002 to June 2004, 34 patients diagnosed cytologically or pathologically with NSCLC, who were candidates for radical radiotherapy or surgery, received PET/CT scanning. Both images were transmitted into treatment planning system (TPS) workstations respectively and were fused and reconstructed. All patients were staged according to the 1997 World Health Organization (WHO) staging system. The impact of PET/CT on the clinical staging of all the patients was determined. The gross tumor volume (GTV) was delineated on the CT imaging and PET/CTfused imaging respectively. Based on the two images, 3D- CRT planning was made respectively at the TPS workstation with Topslane software, the planning target volumes (PTV) being defined with a 15 mm margin around GTV of primary lumps (PTV 1 ) and 7 mm for involved lymph nodes (PTV 2 ). Evaluating indexes including V PTV (volume of PTV, V PTV = V PTV1 + V PTV2 ), V 20 (percentage of the total lung volume receiving more than 20 Gy), MLD (mean lung dose) , TCP (tumor control probability) , NTCP (normal tissue complication probability) , and Ds (dose to spinal cord) were selected to be paralleled to compare the quality of the two plans and the impact of PET/CT on RP was further analyzed. Results: In 13 of 34 (38.2%) cases, PET/CT information changed the clinical staging, 8 of which were upstaged and 5 downstaged. For 10 of 34 (29.4%) cases, PET/CT results modified their management decisions. Among 16 patients performed by surgery, 14 had consistent PET/CT staging with pathologic staging. The sensitivity of PET/CT was 93.3% and accuracy 87.5%. Difference of indexes including V PTV , V 20 and MLD between the two radiation planning was statistically significant, but Ds

Gel dosimetry for conformal radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Gambarini, G [Department of Physics of the University and INFN, Milan (Italy)

2005-07-01

With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

Volumetric modulated arc therapy for delivery of hypofractionated stereotactic lung radiotherapy: A dosimetric and treatment efficiency analysis

International Nuclear Information System (INIS)

McGrath, Samuel D.; Matuszak, Martha M.; Yan Di; Kestin, Larry L.; Martinez, Alvaro A.; Grills, Inga S.

2010-01-01

Purpose/objective(s): Volumetric modulated arc therapy (VMAT) allows for intensity-modulated radiation delivery during gantry rotation with dynamic MLC motion, variable dose rates and gantry speed modulation. We compared VMAT plans with 3D-CRT for hypofractionated lung radiotherapy. Materials/methods: Twenty-one 3D-CRT plans for Stage IA lung cancer previously treated stereotactically were selected. VMAT plans were generated by optimizing machine aperture shape and radiation intensity at 10 deg. intervals. A partial arc range of 180 deg. was manually selected to coincide with tumor location. The arc was resampled down to 5 deg. intervals to ensure dose calculation accuracy. Identical planning objectives were used for VMAT/3D-CRT. Parameters assessed included dose to PTV and organs-at-risk (OAR), monitor units, and multiple conformity and homogeneity indices. Plans were delivered to a phantom for time comparison. Results: Lung V 20/12.5/10/5 were less with VMAT (relative reduction 4.5%, p = .02; 3.2%, p = .01; 2.6%, p = .01; 4.2%, p = .03, respectively). Mean/maximum-doses to PTV, dose to additional OARs, 95% isodose line conformity, and target volume homogeneity were equivalent. VMAT improved conformity at both the 80% (1.87 vs. 1.93, p = .08) and 50% isodose lines (5.19 vs. 5.65, p = .01). Treatment times were reduced significantly with VMAT (mean 6.1 vs. 11.9 min, p < .01). Conclusions: Single arc VMAT planning achieves highly conformal dose distributions while controlling dose to critical structures, including significant reduction in lung dose volume parameters. Employing a VMAT technique decreases treatment times by 37-63%, reducing the chance of error introduced by intrafraction variation. The quality and efficiency of VMAT is ideally suited for stereotactic lung radiotherapy delivery.

Treatment results of radiotherapy for medically inoperable stage I/II non-small cell lung cancer

International Nuclear Information System (INIS)

Zhang Li; Wang Lvhua; Zhang Hongxing; Chen Dongfu; Xiao Zefen; Wang Mei; Feng Qinfu; Liang Jun; Zhou Zongmei; Ou Guangfei; Lv Jima; Yin Weibo

2008-01-01

Objective: To retrospectively analyze treatment results of radiotherapy for medically inoperable stage I/II non-small cell lung cancer. Methods: Between Jan. 2000 and Dec. 2005, fifty-eight such patients were enrolled into the database analysis, including 37 with clinical stage I and 21 with stage II disease. Fifty patients received radiotherapy alone and eight with radiotherapy and chemotherapy. Forty- three patients were treated with 3-D conformal radiotherapy (3D-CRT) and 15 with conventional radiotherapy. Results: The 1-, 2- and 3-year overall survival rates were 85%, 54% and 30%, and the median survival time was 26.2 months for the whole group. The corresponding figures were 88%, 60%, 36% and 30.8 months for cancer-specific survival; 84%, 64%, 31% and 30.8 months for Stage I disease; 81%, 47%, 28% and 18.8 months for Stage II disease; 95%, 57%, 33% and 30.8 months for 3D-CRT group and 53%, 44%, 24% and 15.3 months for conventional radiotherapy group. By logrank test, tumor volume, pneumonitis of Grade II or higher and weight loss more than 5% showed statistically significant impact on overall survival. Tumor volume was the only independent prognostic factor in Cox multivariable regression. Pneumonitis and esophagitis of Grade II or higher were 16% and 2%, respectively. Age and lung function before treatment had a significant relationship with pneumonitis. Failure included the local recurrence (33%) and distant metastasis (21%). There was no difference between the treatment modalities and failure sites. Conclusions: For medically inoperable early stage non-small cell lung cancer patients, tumor volume is the most important prognostic factor for overall survival. The conformal radiotherapy marginally improves the survival. The age and pulmonary function are related to the incidence of treatment induced pneumonitis. (authors)

Dosimetric verification of radiotherapy treatment planning systems in Serbia: national audit

OpenAIRE

Rutonjski Laza; Petrović Borislava; Baucal Milutin; Teodorović Milan; Čudić Ozren; Gershkevitsh Eduard; Izewska Joanna

2012-01-01

Abstract Background Independent external audits play an important role in quality assurance programme in radiation oncology. The audit supported by the IAEA in Serbia was designed to review the whole chain of activities in 3D conformal radiotherapy (3D-CRT) workflow, from patient data acquisition to treatment planning and dose delivery. The audit was based on the IAEA recommendations and focused on dosimetry part of the treatment planning and delivery processes. Methods The audit was conducte...

Time management in radiation oncology: evaluation of time, attendance of medical staff, and resources during radiotherapy for prostate cancer: the DEGRO-QUIRO trial.

Science.gov (United States)

Keilholz, L; Willner, J; Thiel, H-J; Zamboglou, N; Sack, H; Popp, W

2014-01-01

In order to evaluate resource requirements, the German Society of Radiation Oncology (DEGRO) recorded the times needed for core procedures in the radio-oncological treatment of various cancer types within the scope of its QUIRO trial. The present study investigated the personnel and infrastructural resources required in radiotherapy of prostate cancer. The investigation was carried out in the setting of definitive radiotherapy of prostate cancer patients between July and October 2008 at two radiotherapy centers, both with well-trained staff and modern technical facilities at their disposal. Personnel attendance times and room occupancy times required for core procedures (modules) were each measured prospectively by two independently trained observers using time measurements differentiated on the basis of professional group (physician, physicist, and technician), 3D conformal (3D-cRT), and intensity-modulated radiotherapy (IMRT). Total time requirements of 983 min for 3D-cRT and 1485 min for step-and-shoot IMRT were measured for the technician (in terms of professional group) in all modules recorded and over the entire course of radiotherapy for prostate cancer (72-76 Gy). Times needed for the medical specialist/physician were 255 min (3D-cRT) and 271 min (IMRT), times of the physicist were 181 min (3D-cRT) and 213 min (IMRT). The difference in time was significant, although variations in time spans occurred primarily as a result of various problems during patient treatment. This investigation has permitted, for the first time, a realistic estimation of average personnel and infrastructural requirements for core procedures in quality-assured definitive radiotherapy of prostate cancer. The increased time needed for IMRT applies to the step-and-shoot procedure with verification measurements for each irradiation planning.

Interobserver delineation uncertainty in involved-node radiation therapy (INRT) for early-stage Hodgkin lymphoma: on behalf of the Radiotherapy Committee of the EORTC lymphoma group

DEFF Research Database (Denmark)

Aznar, Marianne C.; Girinsky, Theodore; Berthelsen, Anne Kiil

2017-01-01

deviations between the surfaces of the observer and consensus contour (Hausdorff distance). 3D-conformal (3D-CRT) and intensity-modulated radiotherapy (IMRT) plans were calculated for each contour in order to investigate the impact of interobserver variability on each treatment modality. Similar target...... of the systematic error associated with delineation uncertainty, ranged from 1.9 to 3.8 mm (median: 3.2 mm). Variations in mean dose resulting from different observer contours were small and were not higher in IMRT plans than in 3D-CRT plans. CONCLUSIONS: We observed considerable differences in target volume...

Dosimetry study on the conventional and three dimensional conformal radiation treatment planning protocols for rectal cancer

International Nuclear Information System (INIS)

Cai Yong; He Yuxiang; Han Shukui; Wu Hao; Gong Jian; Xu Bo

2007-01-01

Objective: To compare the dose distribution of clinical target volume (CTV), in normal tissues and organs for patients with rectal cancer on the conventional radiotherapy (2D) and three dimension- al conformal radiation treatment (3DCRT). Methods: The CT image data of 36 rectal cancer patients treated with 3DCRT were studied. The CTV, small bowel, colon, bladder, pelvic bone marrow, and femoral head and neck were contoured on consecutive axial slices of CT images. Two 3DCRT and three conventional treatment planning protocols were simulated using three dimensional treatment planning system (CMS Focus 2.31), were defined as 3D-3, 3D-4, 2D-2, 2D-3, 2D-4. The difference of five treatment planning protocols on the CTV and normal structure by analysis of dose-volume histograms (DVHs) were compared. Results: The D 95 and V 95 of these five protocols all exceeded 97%. The conformity index(CI) of 3D was obviously larger than that of 2D protocol. The dose inhomogeneity(DI) in 4 DCRT was less than that of 3 DCRT. The 3D as compared with the 2D, significantly reduced the mean dose of 45 Gy to the small bowel and colon. The 3D-3 as compared with the 2D-3, the 3D-4 as compared with the 2D-4, the mean dose of small bowel and colon was reduced by 28.5% and 25.7%, respectively. The 3D-3 as compared with the 2D-2, the 3D-3 as compared with the 2D-3 and the 3D4 as compared with the 2D-4, the percentage volume of small bowel and colon which received 45 Gy was reduced by 80.8% , 51.1% and 54.7% , respectively. Either the mean dose, or the percentage volume receiving 35 Gy and 45 Gy to the pelvic bone and bladder, the 3D planning protocols had advanage over the 2D planning protocols. The V 45 of bladder in 2D-2 planning proto- col was the highest in all planning protocols, exceeding 98%, but the highest V 45 of bladder was only 50% in the other planning protocols. Conclusions: Even though the difference in pelvic CTV of rectal cancer patients between the conventional radiotherapy and 3

Treatment of primany hepatic carcinoma with three-dimensional conformal radiation therapy combined with transcatheter arterial chemoembolization

International Nuclear Information System (INIS)

Wu Li; Wen Xiaoping; Huang Wei

2006-01-01

Objective: To evaluate the effects of three-dimensional conformal radiation therapy (3DCRT) combined with transcatheter arterial chemoembolization (TACE) on stage m/IV primary hepatic carcinoma. Methods: Eighty cases of stage III/IV primary hepatic carcinoma were randomly divided into two groups: 40 cases treated with three-dimensional conformal radiation therapy combined with transcatheter arterial chemoembolization (3DCRT + TACE group) and 40 cases treated with three-dimensional conformal radiation therapy associated with hepatic arterial infusion chemotherapy (3DCRT +HAI group). Results: The response rates were 75% and 45% in 3DCRT + TACE group and 3DCRT + HAI group, respectively; and the difference between the two groups was statistically significant (P 0.05), The 0.5-, 1- and 2-year survival rates were 73% , 45% and 28% in 3DCRT + TACE group, and 45%, 25% and 13% in 3DCRT + HAI group, respectively; and the difference between the two groups was statistically significant (P 0.05). Conclusion: Three-dimensional conformal radiation therapy combined with transcatheter arterial chemoembolization improved prognosis of stage III/IV primary hepatic carcinoma. (authors)

Phase II study of radiotherapy with three-dimensional conformal boost concurrent with paclitaxel and cisplatin for Stage IIIB non-small-cell lung cancer

International Nuclear Information System (INIS)

Kim, Young Seok; Yoon, Sang Min; Choi, Eun Kyung; Yi, Byong Yong; Kim, Jong Hoon; Ahn, Seung Do; Lee, Sang-wook; Shin, Seong Soo; Lee, Jung Shin; Suh, Cheolwon; Kim, Sang-We; Kim, Dong Soon; Kim, Woo Sung; Park, Heon Joo; Park, Charn Il

2005-01-01

Purpose: To evaluate the efficacy and toxicity of concurrent chemoradiotherapy with paclitaxel/cisplatin for Stage IIIB locally advanced non-small-cell lung cancer (NSCLC). Methods and Materials: Radiotherapy was administered to a total dose of 70.2 Gy (daily fraction of 1.8 Gy, 5 days/wk), over an 8-week period, combined with chemotherapy. The chemotherapy consisted of weekly 40 mg/m 2 of paclitaxel plus 20 mg/m 2 of cisplatin for 8 consecutive weeks. All patients received three-dimensional conformal radiotherapy (3D-CRT), based on computed tomography simulated planning after 41.4 Gy. The median follow-up period of survivors was 24 months. Results: Between January 2000 and October 2002, 135 patients with a median age of 60 years were enrolled and analyzed in this prospective trial. The overall response rate was 75% including 2 cases of complete response. The major patterns of failure were local failure and distant metastasis. The 2-year overall and progression-free survival rates were 37% and 18%, respectively. The median overall and progression-free survival times were 17 months and 9 months, respectively. Hematologic toxicity >Grade 2 was observed in 19% of patients and severe non-hematologic toxicity was infrequent. Conclusions: Three-dimensional conformal radiotherapy, combined with paclitaxel and cisplatin chemotherapy, was associated with a satisfactory outcome with manageable toxicity. Further investigations are needed to improve the local control

Commentary on "Patient-reported outcomes after 3-dimensional conformal, intensity-modulated, or proton beam radiotherapy for localized prostate cancer." Gray PJ, Paly JJ, Yeap BY, Sanda MG, Sandler HM, Michalski JM, Talcott JA, Coen JJ, Hamstra DA, Shipley WU, Hahn SM, Zietman AL, Bekelman JE, Efstathiou JA. Harvard Radiation Oncology Program, Boston, MA.: Cancer 2013;119(9):1729-35. doi: 10.1002/cncr.27956. [Epub 2013 Feb 22].

Science.gov (United States)

Gottschalk, Alexander

2014-04-01

Recent studies have suggested differing toxicity patterns for patients with prostate cancer who receive treatment with 3-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), or proton beam therapy (PBT). The authors reviewed patient-reported outcomes data collected prospectively using validated instruments that assessed bowel and urinary quality of life (QOL) for patients with localized prostate cancer who received 3DCRT (n = 123), IMRT (n = 153) or PBT (n = 95). Clinically meaningful differences in mean QOL scores were defined as those exceeding half the standard deviation of the baseline mean value. Changes from baseline were compared within groups at the first post-treatment follow-up (2-3 months from the start of treatment) and at 12 months and 24 months. At the first post-treatment follow-up, patients who received 3DCRT and IMRT, but not those who received PBT, reported a clinically meaningful decrement in bowel QOL. At 12 months and 24 months, all 3 cohorts reported clinically meaningful decrements in bowel QOL. Patients who received IMRT reported clinically meaningful decrements in the domains of urinary irritation/obstruction and incontinence at the first post-treatment follow-up. At 12 months, patients who received PBT, but not those who received IMRT or 3DCRT, reported a clinically meaningful decrement in the urinary irritation/obstruction domain. At 24 months, none of the 3 cohorts reported clinically meaningful changes in urinary QOL. Patients who received 3DCRT, IMRT, or PBT reported distinct patterns of treatment-related QOL. Although the timing of toxicity varied between the cohorts, patients reported similar modest QOL decrements in the bowel domain and minimal QOL decrements in the urinary domains at 24 months. Prospective randomized trials are needed to further examine these differences. © 2013 Published by Elsevier Inc.

Assessment of improved organ at risk sparing for advanced cervix carcinoma utilizing precision radiotherapy techniques

Energy Technology Data Exchange (ETDEWEB)

Georg, D.; Georg, P.; Hillbrand, M.; Poetter, R.; Mock, U. [Dept. of Radiotherapy, Medical Univ. AKH, Vienna (Austria)

2008-11-15

Purpose: to evaluate the potential benefit of proton therapy and photon based intensity-modulated radiotherapy in comparison to 3-D conformal photon radiotherapy (3D-CRT) in locally advanced cervix cancer. Patients and methods: in five patients with advanced cervix cancer 3D-CRT (four-field box) was compared with intensity modulated photon (IMXT) and proton therapy (IMPT) as well as proton beam therapy (PT) based on passive scattering. Planning target volumes (PTVs) included primary tumor and pelvic and para-aortic lymph nodes. Dose-volume histograms (DVHs) were analyzed for the PTV and various organs at risk (OARs) (rectal wall, bladder, small bowel, colon, femoral heads, and kidneys). In addition dose conformity, dose inhomogeneity and overall volumes of 50% isodoses were assessed. Results: all plans were comparable concerning PTV parameters. Large differences between photon and proton techniques were seen in volumes of the 50% isodoses and conformity indices. DVH for colon and small bowel were significantly improved with PT and IMPT compared to IMXT, with D{sub mean} reductions of 50-80%. Doses to kidneys and femoral heads could also be substantially reduced with PT and IMPT. Sparing of rectum and bladder was superior with protons as well but less pronounced. Conclusion: proton beam RT has significant potential to improve treatment related side effects in the bowel compared to photon beam RT in patients with advanced cervix carcinoma. (orig.)

Assessment of improved organ at risk sparing for advanced cervix carcinoma utilizing precision radiotherapy techniques

International Nuclear Information System (INIS)

Georg, D.; Georg, P.; Hillbrand, M.; Poetter, R.; Mock, U.

2008-01-01

Purpose: to evaluate the potential benefit of proton therapy and photon based intensity-modulated radiotherapy in comparison to 3-D conformal photon radiotherapy (3D-CRT) in locally advanced cervix cancer. Patients and methods: in five patients with advanced cervix cancer 3D-CRT (four-field box) was compared with intensity modulated photon (IMXT) and proton therapy (IMPT) as well as proton beam therapy (PT) based on passive scattering. Planning target volumes (PTVs) included primary tumor and pelvic and para-aortic lymph nodes. Dose-volume histograms (DVHs) were analyzed for the PTV and various organs at risk (OARs) (rectal wall, bladder, small bowel, colon, femoral heads, and kidneys). In addition dose conformity, dose inhomogeneity and overall volumes of 50% isodoses were assessed. Results: all plans were comparable concerning PTV parameters. Large differences between photon and proton techniques were seen in volumes of the 50% isodoses and conformity indices. DVH for colon and small bowel were significantly improved with PT and IMPT compared to IMXT, with D mean reductions of 50-80%. Doses to kidneys and femoral heads could also be substantially reduced with PT and IMPT. Sparing of rectum and bladder was superior with protons as well but less pronounced. Conclusion: proton beam RT has significant potential to improve treatment related side effects in the bowel compared to photon beam RT in patients with advanced cervix carcinoma. (orig.)

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

Left-sided breast cancer irradiation using rotational and fixed-field radiotherapy

International Nuclear Information System (INIS)

Qi, X. Sharon; Liu, Tian X.; Liu, Arthur K.; Newman, Francis; Rabinovitch, Rachel; Kavanagh, Brian; Hu, Y. Angie

2014-01-01

The 3-dimensional conformal radiotherapy (3DCRT) technique is the standard for breast cancer radiotherapy. During treatment planning, not only the coverage of the planning target volume (PTV) but also the minimization of the dose to critical structures, such as the lung, heart, and contralateral breast tissue, need to be considered. Because of the complexity and variations of patient anatomy, more advanced radiotherapy techniques are sometimes desired to better meet the planning goals. In this study, we evaluated external-beam radiation treatment techniques for left breast cancer using various delivery platforms: fixed-field including TomoDirect (TD), static intensity-modulated radiotherapy (sIMRT), and rotational radiotherapy including Elekta volumetric-modulated arc therapy (VMAT) and tomotherapy helical (TH). A total of 10 patients with left-sided breast cancer who did or did not have positive lymph nodes and were previously treated with 3DCRT/sIMRT to the entire breast were selected, their treatment was planned with Monaco VMAT, TD, and TH. Dosimetric parameters including PTV coverage, organ-at-risk (OAR) sparing, dose-volume histograms, and target minimum/maximum/mean doses were evaluated. It is found that for plans providing comparable PTV coverage, the Elekta VMAT plans were generally more inhomogeneous than the TH and TD plans. For the cases with regional node involvement, the average mean doses administered to the heart were 9.2 (± 5.2) and 8.8 (± 3.0) Gy in the VMAT and TH plans compared with 11.9 (± 6.4) and 11.8 (± 9.2) Gy for the 3DCRT and TD plans, respectively, with slightly higher doses given to the contralateral lung or breast or both. On average, the total monitor units for VMAT plans are 11.6% of those TH plans. Our studies have shown that VMAT and TH plans offer certain dosimetric advantages over fixed-field IMRT plans for advanced breast cancer requiring regional nodal treatment. However, for early-stage breast cancer fixed

Late rectal toxicity: dose-volume effects of conformal radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Huang, Eugene H.; Pollack, Alan; Levy, Larry; Starkschall, George; Lei Dong; Rosen, Isaac; Kuban, Deborah A.

2002-01-01

Purpose: To identify dosimetric, anatomic, and clinical factors that correlate with late rectal toxicity after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Methods and Materials: We retrospectively analyzed the dose-volume histograms and clinical records of 163 Stage T1b-T3c prostate cancer patients treated between 1992 and 1999 with 3D-CRT, to a total isocenter dose of 74-78 Gy at The University of Texas M. D. Anderson Cancer Center. The median follow-up was 62 months (range 24-102). All late rectal complications were scored using modified Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. The 6-year toxicity rate was assessed using Kaplan-Meier analysis and the log-rank test. A univariate proportional hazards regression model was used to test the correlation between Grade 2 or higher toxicity and the dosimetric, anatomic, and clinical factors. In a multivariate regression model, clinical factors were added to the dosimetric and anatomic variables to determine whether they significantly altered the risk of developing late toxicity. Results: At 6 years, the rate of developing Grade 2 or higher late rectal toxicity was 25%. A significant volume effect was observed at rectal doses of 60, 70, 75.6, and 78 Gy, and the risk of developing rectal complications increased exponentially as greater volumes were irradiated. Although the percentage of rectal volume treated correlated significantly with the incidence of rectal complications at all dose levels (p 3 of the rectum. Of the clinical variables tested, only a history of hemorrhoids correlated with rectal toxicity (p=0.003). Multivariate analysis showed that the addition of hemorrhoids increased the risk of toxicity for each dosimetric variable found to be significant on univariate analysis (p<0.05 for all comparisons). Conclusion: Dose-volume histogram analyses clearly indicated a volume effect on the probability of developing late rectal complications

Accelerated partial breast irradiation with external beam three-dimensional conformal radiotherapy. Five-year results of a prospective phase II clinical study

Energy Technology Data Exchange (ETDEWEB)

Mozsa, Emoeke [National Institute of Oncology, Centre of Radiotherapy, Budapest (Hungary); Landesklinikum Wiener Neustadt, Department of Radiooncology and Radiotherapy, Wiener Neustadt (Austria); Meszaros, Norbert; Major, Tibor; Froehlich, Georgina; Stelczer, Gabor; Fodor, Janos; Polgar, Csaba [National Institute of Oncology, Centre of Radiotherapy, Budapest (Hungary); Sulyok, Zoltan [National Institute of Oncology, Centre of Surgery, Budapest (Hungary)

2014-05-15

The aim of this study was to report the 5-year results of accelerated partial breast irradiation (APBI) using external beam three-dimensional conformal radiotherapy (3D-CRT). Between 2006 and 2011, 44 patients with low-risk, stage I-II breast cancer underwent breast-conserving surgery. Postoperative APBI was given by means of 3D-CRT using three to five non-coplanar fields. The total dose of APBI was 36.9 Gy (nine fractions of 4.1 Gy b.i.d.). The mean follow-up time was 58.2 months for surviving patients. Survival results, side effects, and cosmetic results were assessed. One (2.3 %) local recurrence was observed, for a 5-year actuarial rate of 3.7 %. Neither regional nor distant failure was observed. Two patients died of internal disease. The 5-year disease-free, cancer-specific, and overall survival rates were 96.3, 100, and 95.1 %, respectively. Acute side effects included grade 1 (G1) erythema in 75 %, G1 parenchymal induration in 46 %, and G1 pain in 46 % of patients. No G2 or higher acute side effect occurred. Late side effects included G1, G2, and G3 fibrosis in 44, 7, and 2 % of patients, respectively, G1 skin pigmentation in 12 %, and G1 pain in 2 %. Asymptomatic fat necrosis occurred in 14 %. Cosmetic results were rated excellent or good in 86 % of cases by the patients themselves and 84 % by the physicians. The 5-year local tumor control, toxicity profile, and cosmetic results of APBI delivered with external beam 3D-CRT are encouraging and comparable to other APBI series. (orig.) [German] Evaluation der 5-Jahres-Ergebnisse bezueglich Ueberleben, Tumorkontrolle, Nebenwirkungen und Kosmetik nach Teilbrustbestrahlung (APBI) mittels 3-D-konformaler, akzelerierter Radiotherapie (3D-CRT). Zwischen 2006 und 2011 wurden 44 Patienten mit Brustkrebs im Stadium I-II und niedrigem Risikoprofil brusterhaltend operiert. Die adjuvante, 3-D-konformale APBI wurde mittels 3-5 nonkoplanarer Feldern durchgefuehrt. Die Gesamtdosis betrug 36,9 Gy bei 9 -mal 4,1 Gy b.i.d.. Nach

Results of different modes conformal radiotherapy in treatment of cervical cancer

International Nuclear Information System (INIS)

Baranovs'ka, L.M.; Yivankova, V.S.; Khrulenko, T.V.; Skomorokhova, T.V.; Gorelyina, G.L.

2017-01-01

Development of techniques for cytotoxic treatment applying different modes of conformal radiotherapy, brachytherapy and high-energy (high dose rate - HDR) is one of the promising areas of optimization and efficiency of conservative treatment of patients with regional forms of cervical cancer. At Radiation Oncology Department, National Cancer Institute, 89 patients with stage 2b-3b cervical cancer, aged 29 to 70, underwent examination and combined radiotherapy course. The patients were divided into 2 main groups (56 patients) depending on the mode of developed conformal radiation therapy, and a control group made up by 33 patients (classic, default conformal radiotherapy). Results. Along with external beam radiotherapy, the patients of Group 2 were provided with conformal radiotherapy carried out by means of the linear accelerator of electrons in the mode of enhanced multi fractionation of irradiation dose applied to the small pelvis area (tumor and lymph efflux channels) with the single tumor dose 1.3 Gy twice per day once 4-6 hours up to the total radiation dose of 45 Gy applied to the small pelvis lymph nodes. The patients of Group 1 and the ones of the control group underwent conformal radiotherapy in the mode of standard fractionation applied to the small pelvis area with the single tumor dose of 1.8 Gy up to the total radiation dose of 45 Gy. Conformal radiotherapy was carried out for the patients of Group 1 associated with chemoradiomodifiers (tegafur, cisplatin). At the stage 2 of combined radiotherapy course, all patients underwent HDR brachytherapy via Co60 source in the mode of the single tumor dose of 5 Gy at point A up to the total radiation dose of 35-40 Gy. Therefore, employing accelerated mode of multifractiation in conformal radiotherapy of patients with regional cervical cancer makes it possible to enhance canrcinocidal irradiation doses applied to a tumor, and an interval between radiotherapy fractions provides conditions for initiation of

Parotid gland-recovery after radiotherapy in the head and neck region - 36 months follow-up of a prospective clinical study

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Vordermark Dirk

2011-09-01

Full Text Available Abstract Background The aim of the present study was to evaluate the recovery potential of the parotid glands after using either 3D-conformal-radiotherapy (3D-CRT or intensity-modulated radiotherapy (IMRT by sparing one single parotid gland. Methods Between 06/2002 and 10/2008, 117 patients with head and neck cancer were included in this prospective, non-randomised clinical study. All patients were treated with curative intent. Salivary gland function was assessed by measuring stimulated salivary flow at the beginning, during and at the end of radiotherapy as well as 1, 6, 12, 24, and 36 months after treatment. Measurements were converted to flow rates and normalized relative to rates before treatment. Mean doses (Dmean were calculated from dose-volume histograms based on computed tomographies of the parotid glands. Results Patients were grouped according to the Dmean of the spared parotid gland having the lowest radiation exposure: Group I - Dmean mean 26-40 Gy (n = 45, and group III - Dmean > 40 Gy (n = 36. 15/117 (13% patients received IMRT. By using IMRT as compared to 3D-CRT the Dmean of the spared parotid gland could be significantly reduced (Dmean IMRT vs. 3D-CRT: 21.7 vs. 34.4 Gy, p Conclusions If a Dmean mean of the parotids, and thus on the saliva flow and recovery of parotid gland.

Helical tomo-therapy in the anal canal cancer: dosimetric comparison with conformal radiotherapy with intensity modulation and classical conformal radiotherapy

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Ozsahin, M.; Ugurluer, G.; Ballerini, G.; Letenneur, G.; Zouhair, A.; Mirimanoff, R.O.

2009-01-01

A dosimetry comparison was made between helical tomo-therapy, I.M.R.T. and classical conformal three dimensional radiotherapy for twelve first patients that received a image guided radiotherapy, the toxicity was tackled with a minimum follow-up of fourteen months. In conclusion, the CT-guided radiotherapy allows to save organs at risks superior to I.M.R.T. and conformal radiotherapy and a best homogeneity in the target volume. the toxicity is moderated and the break time is limited. (N.C.)

Intensity modulated radiotherapy in early stage Hodgkin lymphoma patients: Is it better than three dimensional conformal radiotherapy?

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De Sanctis, Vitaliana; Chiacchiararelli, Laura; Enrici, Riccardo Maurizi; Bolzan, Chiara; D’Arienzo, Marco; Bracci, Stefano; Fanelli, Alessandro; Cox, Maria Christina; Valeriani, Maurizio; Osti, Mattia F; Minniti, Giuseppe

2012-01-01

Cure rate of early Hodgkin Lymphoma are high and avoidance of late toxicities is of paramount importance. This comparative study aims to assess the normal tissue sparing capability of intensity-modulated radiation therapy (IMRT) versus standard three-dimensional conformal radiotherapy (3D-CRT) in terms of dose-volume parameters and normal tissue complication probability (NTCP) for different organs at risk in supradiaphragmatic Hodgkin Lymphoma (HL) patients. Ten HL patients were actually treated with 3D-CRT and all treatments were then re-planned with IMRT. Dose-volume parameters for thyroid, oesophagus, heart, coronary arteries, lung, spinal cord and breast were evaluated. Dose-volume histograms generated by TPS were analyzed to predict the NTCP for the considered organs at risk, according to different endpoints. Regarding dose-volume parameters no statistically significant differences were recorded for heart and origin of coronary arteries. We recorded statistically significant lower V30 with IMRT for oesophagus (6.42 vs 0.33, p = 0.02) and lungs (4.7 vs 0.1 p = 0.014 for the left lung and 2.59 vs 0.1 p = 0.017 for the right lung) and lower V20 for spinal cord (17.8 vs 7.2 p = 0.02). Moreover the maximum dose to the spinal cord was lower with IMRT (30.2 vs 19.9, p <0.001). Higher V10 with IMRT for thyroid (64.8 vs 95, p = 0.0019) and V5 for lungs (30.3 vs 44.8, p = 0.03, for right lung and 28.9 vs 48.1, p = 0.001 for left lung) were found, respectively. Higher V5 and V10 for breasts were found with IMRT (V5: 4.14 vs 20.6, p = 0.018 for left breast and 3.3 vs 17, p = 0.059 for right breast; V10: 2.5 vs 13.6 p = 0.035 for left breast and 1.7 vs 11, p = 0.07 for the right breast.) As for the NTCP, our data point out that IMRT is not always likely to significantly increase the NTCP to OARs. In HL male patients IMRT seems feasible and accurate while for women HL patients IMRT should be used with caution

Hyperfractionated 3D conformal radiotherapy and concurrent chemotherapy for unresectable stage III non-small cell lung cancer

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Choi, E.K.; Ahn, S.D.; Yi, B.Y.; Chang, H.S.; Lee, J.H.; Suh, C.W.; Lee, J.S.; Kim, S.H.; Koh, Y.S.; Kim, W.S.; Kim, D.S.; Kim, W.D.; Sohn, K.H.

1997-01-01

Purpose/Objective: This phase II study has been conducted to determine the feasibility, toxicity, response rate, local control, distant metastasis, and survival of hyperfractionated 3D conformal radiotherapy and concurrent chemotherapy with mitomycin C, vinblastine, and cisplatin in unresectable stage III non-small cell lung cancer (NSCLC), and also to find the most ideal 3D conformal radiotherapy technique. Materials and Methods: From Aug 1993, 173 patients with unresectable stage III NSCLC were entered into this trial and 146 (84%) completed the treatment. Hyperfractionated radiotherapy was given to a total dose of 65-70 Gy (120 cGy/fx, bid) with concurrent 2 cycles of MVP chemotherapy (Mitomycin C 6 mg/m 2 d2 and d29, Vinblastine 6 mg/m 2 d2 and d29, Cisplatin 60 mg/m 2 d1 and d28). Of these 146 patients who completed the treatment, 78 received noncoplanar 3D conformal radiotherapy using 4-6 fields and 17 received coplanar segmented conformal radiotherapy. Clinical tumor response was assessed one month after the completion of radiotherapy by computerized tomography (CT) scan. Toxicity was graded by RTOG and SWOG criteria. Normal tissue complication probability (NTCP) for lung was calculated to find the correlation with radiation pneumonitis. Results: Nineteen (13%) had stage IIIa and 127 (87%) had IIIb disease including 16 with pleural effusion and 20 with supraclavicular lymph node metastases. Response rate was 74%, including 20% complete response and 54% partial response. With a minimum follow up of 12 months, overall survival was 60% at 1 year, 30% at 2 years and median survival was 15 months. Patients achieving a complete response (n=29) had a 2-year overall survival of 46.5% compared to 28.7% for partial responders (n=79) (p=.001). Actuarial local control was 66.7% at 1 year and 43.7% at 2 years. Actuarial distant free survival was 52.3% at 1 year and 39.8% at 2 years. Major hematologic toxicity (Gr 3-4) occurred in 33% of the patients but treatment delay

Results and DVH analysis of late rectal bleeding in patients treated with 3D-CRT or IMRT for localized prostate cancer

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Someya, Masanori; Hori, Masakazu; Tateoka, Kunihiko; Nakata, Kensei; Saito, Masato; Hirokawa, Naoki; Sakata, Koh-ichi; Takagi, Masaru; Hareyama, Masato

2015-01-01

In patients undergoing radiotherapy for localized prostate cancer, dose-volume histograms and clinical variables were examined to search for correlations between radiation treatment planning parameters and late rectal bleeding. We analyzed 129 patients with localized prostate cancer who were managed from 2002 to 2010 at our institution. They were treated with 3D conformal radiation therapy (3D-CRT, 70 Gy/35 fractions, 55 patients) or intensity-modulated radiation therapy (IMRT, 76 Gy/38 fractions, 74 patients). All radiation treatment plans were retrospectively reconstructed, dose-volume histograms of the rectum were generated, and the doses delivered to the rectum were calculated. Time to rectal bleeding ranged from 9 - 53 months, with a median of 18.7 months. Of the 129 patients, 33 patients had Grade 1 bleeding and were treated with steroid suppositories, while 25 patients with Grade 2 bleeding received argon plasma laser coagulation therapy (APC). Three patients with Grade 3 bleeding required both APC and blood transfusion. The 5-year incidence rate of Grade 2 or 3 rectal bleeding was 21.8% for the 3D-CRT group and 21.6% for the IMRT group. Univariate analysis showed significant differences in the average values from V65 to V10 between Grades 0 - 1 and Grades 2 - 3. Multivariate analysis demonstrated that patients with V65 ≥ 17% had a significantly increased risk (P = 0.032) of Grade 2 or 3 rectal bleeding. Of the 28 patients of Grade 2 or 3 rectal bleeding, 17 patients (60.7%) were cured by a single session of APC, while the other 11 patients required two sessions. Thus, none of the patients had any further rectal bleeding after the second APC session. (author)

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

Science.gov (United States)

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-01-01

Introduction Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. Methods A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. Results The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. Conclusion The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques. PMID:26229623

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

International Nuclear Information System (INIS)

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-01-01

Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT).

Science.gov (United States)

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-12-01

Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147-53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose-volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

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Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham [Andrew Love Cancer Centre, Geelong Hospital, Geelong, Victoria (Australia)

2013-12-15

Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.

Radiation dose verification using real tissue phantom in modern radiotherapy techniques

International Nuclear Information System (INIS)

Gurjar, Om Prakash; Mishra, S.P.; Bhandari, Virendra; Pathak, Pankaj; Patel, Prapti; Shrivastav, Garima

2014-01-01

In vitro dosimetric verification prior to patient treatment has a key role in accurate and precision radiotherapy treatment delivery. Most of commercially available dosimetric phantoms have almost homogeneous density throughout their volume, while real interior of patient body has variable and varying densities inside. In this study an attempt has been made to verify the physical dosimetry in actual human body scenario by using goat head as 'head phantom' and goat meat as 'tissue phantom'. The mean percentage variation between planned and measured doses was found to be 2.48 (standard deviation (SD): 0.74), 2.36 (SD: 0.77), 3.62 (SD: 1.05), and 3.31 (SD: 0.78) for three-dimensional conformal radiotherapy (3DCRT) (head phantom), intensity modulated radiotherapy (IMRT; head phantom), 3DCRT (tissue phantom), and IMRT (tissue phantom), respectively. Although percentage variations in case of head phantom were within tolerance limit (< ± 3%), but still it is higher than the results obtained by using commercially available phantoms. And the percentage variations in most of cases of tissue phantom were out of tolerance limit. On the basis of these preliminary results it is logical and rational to develop radiation dosimetry methods based on real human body and also to develop an artificial phantom which should truly represent the interior of human body. (author)

Radiation dose verification using real tissue phantom in modern radiotherapy techniques

Directory of Open Access Journals (Sweden)

Om Prakash Gurjar

2014-01-01

Full Text Available In vitro dosimetric verification prior to patient treatment has a key role in accurate and precision radiotherapy treatment delivery. Most of commercially available dosimetric phantoms have almost homogeneous density throughout their volume, while real interior of patient body has variable and varying densities inside. In this study an attempt has been made to verify the physical dosimetry in actual human body scenario by using goat head as "head phantom" and goat meat as "tissue phantom". The mean percentage variation between planned and measured doses was found to be 2.48 (standard deviation (SD: 0.74, 2.36 (SD: 0.77, 3.62 (SD: 1.05, and 3.31 (SD: 0.78 for three-dimensional conformal radiotherapy (3DCRT (head phantom, intensity modulated radiotherapy (IMRT; head phantom, 3DCRT (tissue phantom, and IMRT (tissue phantom, respectively. Although percentage variations in case of head phantom were within tolerance limit (< ± 3%, but still it is higher than the results obtained by using commercially available phantoms. And the percentage variations in most of cases of tissue phantom were out of tolerance limit. On the basis of these preliminary results it is logical and rational to develop radiation dosimetry methods based on real human body and also to develop an artificial phantom which should truly represent the interior of human body.

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

Patient outcomes of monotherapy with hypofractionated three-dimensional conformal radiation therapy for stage T2 or T3 non-small cell lung cancer: a retrospective study

International Nuclear Information System (INIS)

Sakaguchi, Masakuni; Maebayashi, Toshiya; Aizawa, Takuya; Ishibashi, Naoya; Fukushima, Shoko; Abe, Osamu; Saito, Tsutomu

2016-01-01

Hypofractionated three-dimensional conformal radiation therapy (3D-CRT) is a treatment option for patients with early-stage non-small cell lung cancer (NSCLC) who are medically unable to tolerate surgery and who are not amenable to treatment with stereotactic body radiotherapy. This study assessed the efficacy and safety of 3D-CRT as a monotherapy in patients with localized stage T2 or T3 NSCLC. This retrospective study consisted of 29 patients (20 males) aged 56–89 years (median, 76 years) with histologically confirmed NSCLC who underwent 3D-CRT between 2005 and 2014. The median duration of patient observation was 17.0 months (range, 1.0–64.0 months). Complete and partial responses occurred in 13.8 and 44.8 % of patients, respectively, and the overall response rate was 58.2 %. Meanwhile, the 1- and 3-year survival rates were 65.8 and 33.8 %, respectively. In T2 NSCLC, the median survival time (MST) was 12 months, and the 1- and 3-year survival rates were 62.4 and 21.4 %, respectively. In T3 NSCLC, the MST was 17 months, and the 1- and 3-year survival rates were 72.9 and 48.6 %, respectively. Severe toxicities (Common Terminology Criteria Grade 3) were not observed. The mean biologically effective dose required to improve local control exceeded 80 Gy (range, 67.2–96.0 Gy). These findings support a role for 3D-CRT as a treatment option for patients who refuse or could not tolerate surgical therapy with early-stage NSCLC. Although this was a small, retrospective study, it may form the basis for future, larger controlled studies on 3D-CRT as a monotherapy for NSCLC

Late toxicity after conformal and intensity-modulated radiation therapy for prostate cancer. Impact of previous surgery for benign prostatic hyperplasia

International Nuclear Information System (INIS)

Odrazka, K.; Dolezel, M.; Vanasek, J.

2010-01-01

The objective of this study was to retrospectively compare late toxicity of conventional-dose three-dimensional conformal radiation therapy (3D-CRT) and high-dose intensity-modulated radiation therapy (IMRT) for prostate cancer. A total of 340 patients with T1-3 prostate cancer were treated with 3D-CRT (n=228) and IMRT (n=112). The median follow-up time was 5.9 years and 3.0 years, respectively. The prescription dose was 70 Gy for 3D-CRT and 78 Gy for IMRT. Late gastrointestinal (GI) and genitourinary (GU) toxicities were graded according to the Fox Chase modification of the Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. There was no difference between 3D-CRT and IMRT in the incidence of GI and GU toxicity at 3 years. On multivariate analysis, transurethral resection of prostate/open transvesical prostatectomy (TURP/TVPE) for benign prostatic hyperplasia, carried out before radiotherapy, significantly increased the risk of Grade ≥2 GU toxicity (risk ratio 1.88). Among patients who experienced TURP/TVPE, the 5-year actuarial likelihood of Grade 2-3 urinary incontinence was 23%, compared with 9% for those without prostate surgery (P=0.01). Tolerance of 3D-CRT and IMRT was similar, despite the use of high radiation dose with IMRT. Previous TURP/TVPE increased the risk of GU toxicity. (author)

Cost-benefit analysis of 3D conformal radiation therapy. Treatment of prostate cancer as a model

International Nuclear Information System (INIS)

Cho, K.H.; Khan, F.M.; Levitt, S.H.

1999-01-01

Three-dimensional conformal radiation therapy (3D-CRT) is a promising new treatment technique based on the principle that improved precision in both tumor definition and dose delivery will enhance outcomes by maximizing dose to the tumor area while minimizing dose to normal tissue. Using a cost-benefit analysis, in terms of outcomes, we first examined the overall risks and benefits of 3D-CRT. We then used the treatment of prostate cancer as a model to compare actual clinical outcomes reported between 3D-CRT and standard radiation therapy (SRT). Our analysis shows that application of 3D-CRT to the clinical setting remains difficult because of the continual difficulties of target definition, and that dose escalation cannot yet be justified on the basis of the lack of benefit found, and suggested increased late toxicity, in most of the dose escalation series compared with SRT. (orig.)

Dosimetric reproduction of a left-breast 3DCRT field-in-field radiation therapy planning in an anthropomorphic and anthropometric phantom

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Nogueira, Luciana B., E-mail: lucibn19@yahoo.com.br, E-mail: jonymarques@uol.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Anatomia e Imagem; Barsanelli, Cristiane; Geraldo, Jony M., E-mail: cbarsanelli@yahoo.com.br [Hospital Luxemburgo, Instituto Mário Penna, Belo Horizonte, MG (Brazil); Aquino, Jean Carlos; Campos, Tarcísio P. Ribeiro, E-mail: jeancarlosaquino@outlook.com, E-mail: tprcampos@yahoo.com.br [Universidade Federal de Minas Gerais (UGMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2017-07-01

The proposal of this study was to reproduce the dosimetry established in a treatment planning system (TPS) following a 3D conformational radiation therapy (3DCRT) protocol of two parallel-opposite fields applied to the left-breast in a thorax phantom, with the use of the field-in-field technique. Computed tomography (CT) images of the anthropomorphic and anthropometric phantom of the thorax with mobile breasts were generated. This phantom was developed by the NRI / UFMG research group. The generated images were transferred to the planning system XiO version-5 for the elaboration of the breast tele therapeutic planning with 2 Gy per fraction, in 25 fractions, with prescribed dose of 50 Gy. A set of ten EBT2 radiochromic films were irradiated at different doses. The values of RGB (Red, Green, Blue) of the radiochromic films were obtained by scanning and data transformed in optical density (OD), whose values were used to construct the calibration curve. EBT2 radiochromic films were positioned outside and inside of the thorax phantom: internally in the right and left lungs, on the face of the heart, in the glandular breast tissue-equivalent (TE) and in the left breast skin. After phantom radiation at the linear accelerator 6 MV Elekta Precise reproducing the 3DCRT, the radiochromic films were digitized after 24 h of exposure. The measurements of the intensities of the films in RGB were measured in the software ImageJ, transformed in optical density and converted in bidimensional dose distributions, applying the calibration curve. The experimental dosimetric data were analyzed and compared with values generated in the TPS. In addition, graphics and dose-volume histograms (DVH) were developed. The dose measurements in the glandular-TE in breast did not present statistically significant differences in relation to values at equivalent positions generated in the TPS. The organs at risk received doses below the reference values, according to TPS. It was verified the

Dosimetric reproduction of a left-breast 3DCRT field-in-field radiation therapy planning in an anthropomorphic and anthropometric phantom

International Nuclear Information System (INIS)

Nogueira, Luciana B.; Aquino, Jean Carlos; Campos, Tarcísio P. Ribeiro

2017-01-01

The proposal of this study was to reproduce the dosimetry established in a treatment planning system (TPS) following a 3D conformational radiation therapy (3DCRT) protocol of two parallel-opposite fields applied to the left-breast in a thorax phantom, with the use of the field-in-field technique. Computed tomography (CT) images of the anthropomorphic and anthropometric phantom of the thorax with mobile breasts were generated. This phantom was developed by the NRI / UFMG research group. The generated images were transferred to the planning system XiO version-5 for the elaboration of the breast tele therapeutic planning with 2 Gy per fraction, in 25 fractions, with prescribed dose of 50 Gy. A set of ten EBT2 radiochromic films were irradiated at different doses. The values of RGB (Red, Green, Blue) of the radiochromic films were obtained by scanning and data transformed in optical density (OD), whose values were used to construct the calibration curve. EBT2 radiochromic films were positioned outside and inside of the thorax phantom: internally in the right and left lungs, on the face of the heart, in the glandular breast tissue-equivalent (TE) and in the left breast skin. After phantom radiation at the linear accelerator 6 MV Elekta Precise reproducing the 3DCRT, the radiochromic films were digitized after 24 h of exposure. The measurements of the intensities of the films in RGB were measured in the software ImageJ, transformed in optical density and converted in bidimensional dose distributions, applying the calibration curve. The experimental dosimetric data were analyzed and compared with values generated in the TPS. In addition, graphics and dose-volume histograms (DVH) were developed. The dose measurements in the glandular-TE in breast did not present statistically significant differences in relation to values at equivalent positions generated in the TPS. The organs at risk received doses below the reference values, according to TPS. It was verified the

Phase I Study of Concurrent High-Dose Three-Dimensional Conformal Radiotherapy With Chemotherapy Using Cisplatin and Vinorelbine for Unresectable Stage III Non-Small-Cell Lung Cancer

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Sekine, Ikuo, E-mail: isekine@ncc.go.jp [Division of Internal Medicine and Thoracic Oncology, National Cancer Center Hospital, Tokyo (Japan); Sumi, Minako; Ito, Yoshinori [Division of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Horinouchi, Hidehito; Nokihara, Hiroshi; Yamamoto, Noboru; Kunitoh, Hideo; Ohe, Yuichiro; Kubota, Kaoru; Tamura, Tomohide [Division of Internal Medicine and Thoracic Oncology, National Cancer Center Hospital, Tokyo (Japan)

2012-02-01

Purpose: To determine the maximum tolerated dose in concurrent three-dimensional conformal radiotherapy (3D-CRT) with chemotherapy for unresectable Stage III non-small-cell lung cancer (NSCLC). Patients and Methods: Eligible patients with unresectable Stage III NSCLC, age {>=}20 years, performance status 0-1, percent of volume of normal lung receiving 20 GY or more (V{sub 20}) {<=}30% received three to four cycles of cisplatin (80 mg/m{sup 2} Day 1) and vinorelbine (20 mg/m{sup 2} Days 1 and 8) repeated every 4 weeks. The doses of 3D-CRT were 66 Gy, 72 Gy, and 78 Gy at dose levels 1 to 3, respectively. Results: Of the 17, 16, and 24 patients assessed for eligibility, 13 (76%), 12 (75%), and 6 (25%) were enrolled at dose levels 1 to 3, respectively. The main reasons for exclusion were V{sub 20} >30% (n = 10) and overdose to the esophagus (n = 8) and brachial plexus (n = 2). There were 26 men and 5 women, with a median age of 60 years (range, 41-75). The full planned dose of radiotherapy could be administered to all the patients. Grade 3-4 neutropenia and febrile neutropenia were noted in 24 (77%) and 5 (16%) of the 31 patients, respectively. Grade 4 infection, Grade 3 esophagitis, and Grade 3 pulmonary toxicity were noted in 1 patient, 2 patients, and 1 patient, respectively. The dose-limiting toxicity was noted in 17% of the patients at each dose level. The median survival and 3-year and 4-year survival rates were 41.9 months, 72.3%, and 49.2%, respectively. Conclusions: 72 Gy was the maximum dose that could be achieved in most patients, given the predetermined normal tissue constraints.

Comparative study of four advanced 3d-conformal radiation therapy treatment planning techniques for head and neck cancer

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Herrassi, Mohamed Yassine; Bentayeb, Farida; Malisan, Maria Rosa

2013-01-01

For the head-and-neck cancer bilateral irradiation, intensity-modulated radiation therapy (IMRT) is the most reported technique as it enables both target dose coverage and organ-at-risk (OAR) sparing. However, during the last 20 years, three-dimensional conformal radiotherapy (3DCRT) techniques have been introduced, which are tailored to improve the classic shrinking field technique, as regards both planning target volume (PTV) dose conformality and sparing of OARs, such as parotid glands and spinal cord. In this study, we tested experimentally in a sample of 13 patients, four of these advanced 3DCRT techniques, all using photon beams only and a unique isocentre, namely Bellinzona, Forward-Planned Multisegments (FPMS), ConPas, and field-in-field (FIF) techniques. Statistical analysis of the main dosimetric parameters of PTV and OARs DVHs as well as of homogeneity and conformity indexes was carried out in order to compare the performance of each technique. The results show that the PTV dose coverage is adequate for all the techniques, with the FPMS techniques providing the highest value for D95%; on the other hand, the best sparing of parotid glands is achieved using the FIF and ConPas techniques, with a mean dose of 26 Gy to parotid glands for a PTV prescription dose of 54 Gy. After taking into account both PTV coverage and parotid sparing, the best global performance was achieved by the FIF technique with results comparable to that of IMRT plans. This technique can be proposed as a valid alternative when IMRT equipment is not available or patient is not suitable for IMRT treatment. (author)

Radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma: Dosimetric comparison and risk assessment of solid secondary cancer

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Bae, Sun Hyun; Park, Hee Chul; Lim, Do Hoon [Dept. of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Dong Wook [Dept. of Radiation Oncology, Kyung Hee University Hospital at Gangdong, Seoul (Korea, Republic of); Kim, Mi Sook [Dept. of Radiation Oncology, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Shin, Myung Hee [Dept. of Social and Preventive Medicine, Sungkyunkwan University School of Medicine, Suwon (Korea, Republic of)

2017-03-15

We compared the dosimetric parameters and the risk of solid secondary cancer from scattered doses among anterior-posterior/posterior-anterior parallel-opposed fields (AP/PA), anterior, posterior, right, and left lateral fields (4{sub f}ield), 3-dimensional conformal radiotherapy (3D-CRT) using noncoplanar beams, and intensity-modulated radiotherapy composed of 7 coplanar beams (IMRT{sub c}o) and 7 coplanar and noncoplanar beams (IMRT{sub n}on). We retrospectively generated 5 planning techniques for 5 patients with gastric MALToma. Homogeneity index (HI), conformity index (CI), and mean doses of the kidney and liver were calculated from the dose-volume histograms. Applied the Biological Effects of Ionizing Radiation VII report to scattered doses, the lifetime attributable risk (LAR) was calculated to estimate the risk of solid secondary cancer. The best value of CI was obtained with IMRT, although the HI varied among patients. The mean kidney dose was the highest with AP/PA, followed by 4{sub f}ield, 3D-CRT, IMRT{sub c}o, and IMRT{sub n}on. On the other hand, the mean liver dose was the highest with 4{sub f}ield and the lowest with AP/PA. Compared with 4{sub f}ield, the LAR for 3D-CRT decreased except the lungs, and the LAR for IMRT{sub c}o and IMRT{sub n}on increased except the lungs. However, the absolute differences were much lower than <1%. Tailored RT techniques seem to be beneficial because it could achieve adjacent organ sparing with very small and clinically irrelevant increase of secondary solid cancer risk compared to the conventional techniques.

Doses to head and neck normal tissues for early stage Hodgkin lymphoma after involved node radiotherapy

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Maraldo, M.V.; Brodin, N.P.; Aznar, M.C.; Vogelius, I.R.; Munck af Rosenschöld, P.; Petersen, P.M.; Specht, L.

2014-01-01

Purpose: To evaluate dose plans for head and neck organs at risk (OARs) for classical Hodgkin lymphoma (HL) patients using involved node radiotherapy (INRT) delivered as 3D conformal radiotherapy (3DCRT), volumetric modulated arc therapy (VMAT), and intensity modulated proton therapy (PT), in comparison to the past mantle field (MF). Materials and methods: Data from 37 patients with cervical lymph node involvement were used. All patients originally received chemotherapy followed by 3DCRT–INRT (30.6 Gy). A VMAT–INRT, PT–INRT (both 30.6 Gy), and a MF plan (36 Gy) were simulated. Doses to head and neck OARs were compared with cumulative DVHs and repeated measures ANOVA. Results: The estimated median mean doses were 15.3, 19.3, 15.4, and 37.3 Gy (thyroid), 10.9, 12.0, 7.9, and 34.5 Gy (neck muscles), 2.3, 11.1, 1.8, and 37.1 Gy (larynx), 1.7, 5.1, 1.3, and 23.8 Gy (pharynx), 0.5, 0.8, 0.01, and 32.3 Gy (ipsilateral parotid), and 2.4, 3.8, 0.7, and 34.7 Gy (ipsilateral submandibular) with 3DCRT, VMAT, PT, and MF (all p < 0.0001), respectively. Conclusion: The use of INRT significantly lowered the estimated radiation dose to the head and neck OARs. VMAT appeared suboptimal compared to 3DCRT and PT, and for some patients, PT offered an additional gain

Induction chemotherapy combined with three-dimensional conformal radiation therapy for locally advanced non-small cell lung cancer

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Zheng Aiqing; Yu Jinming; Zhao Xianguang; Wang Xuetao; Wei Guangsheng

2005-01-01

Objective: To evaluate the effect and complication of induction chemotherapy combined with three-dimensional conformal radiation therapy (3DCRT) for locally advanced non small cell lung cancer (NSCLC). Methods: Ninety-two such patients were randomized into radiation therapy alone group(RT-, 50 patients) and induction chemotherapy combined radiotherapy group (CMT-, 42 patients). The induction chemotherapy consisted of 2-4 cycles of platinum-based regimen. Results: The overall median survival time was 15 months with 12 months in the RT group and 18 months in the CMT group (P=0.014) respectively. The 1-year overall survival rates were 48.6% and 71.2% in RT and CMT group, respectively (P=0.004). The 2-year survival rates were 20.8% and 37.6% in RT and CMT group, respectively (P=0.041). Treatment was well tolerated and the toxicities were similar in either group. Conclusion: The addition of induction chemotherapy to 3DCRT takes a survival advantage over 3DCRT alone for Stage III NSCLC without increasing toxicities. (authors)

Outcome of three-dimensional conformal radiation therapy and intensity-modulated radiation therapy for inoperable locally advanced pancreatic cancer

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Lu Ningning; Jin Jing; Li Yexiong; Yu Zihao; Liu Xinfan; Wang Weihu; Wang Shulian; Song Yongwen; Liu Yuping

2009-01-01

Objective: To evaluate the outcome of radiotherapy for locally advanced pancreatic cancer. Methods: From January 2000 to December 2007, 41 patients with inoperable locally advanced (stage III) pancreatic cancer were treated with three-dimensional conformal radiation therapy(3DCRT) or intensity-modulated radiation therapy (IMRT). Among these patients, 30 received concurrent radio-chemo-therapy. Results: The median survival time(MST) and 1-year overall survival were 9.2 months and 23%. Patients with pretreatment KPS ≥ 80, no regional lymph nodes metastasis, and CR/PR after radiotherapy had better prognosis. The corresponding MSTs were 11.1 months vs 5.8 months (χ 2 =7.50, P=0.006), 10.8 months vs 6.5 months(χ 2 =5.67, P=0.017), and 19.5 months vs 9.1 months (χ 2 =7.28, P=0.007), respectively. Concurrent radio-chemotherapy tended to improve the overall survival(χ 2 =3.25, P=0.072). After radiotherapy, 18 patients had clinical benefit response, mainly being abdominal pain relief. Neither grade 4 hematologic nor grade 3 non-hematologic toxicities were observed. Conclusions: For patients with locally advanced pancreatic cancer, both 3DCRT and IMRT are effective in alleviation of disease-related symptoms. Patients with better performance status before treatment, no regional lymph nodes metastasis, and better response to radiotherapy may have better prognosis. Concurrent radio-chemotherapy trend to improve overall survival when compared with radiotherapy alone. (authors)

Intensity-modulated radiotherapy for laryngeal and hypopharyngeal cancer. Minimization of late dysphagia without jeopardizing tumor control

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Modesto, Anouchka; Laprie, Anne; Graff, Pierre; Rives, Michel [Institut Universitaire du Cancer, Department of Radiation Oncology, Institut Claudius Regaud, Toulouse (France); Vieillevigne, Laure [Institut Universitaire du Cancer, Department of Medical Physics, Toulouse (France); Sarini, Jerome; Vergez, Sebastien; Farenc, Jean-Claude [Institut Universitaire du Cancer, Department of Head and Neck Surgery, Toulouse (France); Delord, Jean-Pierre [Institut Universitaire du Cancer, Department of Medical Oncology, Toulouse (France); Vigarios, Emmanuelle [Centre Hospitalo Universitaire de Rangueil, Dental Surgery Department, Toulouse (France); Filleron, Thomas [Institut Universitaire du Cancer, Department of Biostatistics, Toulouse (France)

2014-11-01

The purpose of this work was to retrospectively determine the value of intensity-modulated radiotherapy (IMRT) in patients with laryngeal and hypopharyngeal squamous cell carcinoma (LHSCC), on outcome and treatment-related toxicity compared to 3-dimensional conformal radiotherapy (3D-CRT). A total of 175 consecutive patients were treated between 2007 and 2012 at our institution with curative intent RT and were included in this study: 90 were treated with 3D-CRT and 85 with IMRT. Oncologic outcomes were estimated using Kaplan-Meier statistics; acute and late toxicities were scored according to the Common Toxicity Criteria for Adverse Events scale v 3.0. Median follow-up was 35 months (range 32-42 months; 95% confidence interval 95 %). Two-year disease-free survival did not vary, regardless of the technique used (69 % for 3D-CRT vs. 72 %; for IMRT, p = 0.16). Variables evaluated as severe late toxicities were all statistically lower with IMRT compared with 3D-CRT: xerostomia (0 vs. 12 %; p < 0.0001), dysphagia (4 vs. 26 %; p < 0.0001), and feeding-tube dependency (1 vs 13 %; p = 0.0044). The rates of overall grade ≥ 3 late toxicities for the IMRT and 3D-CRT groups were 4.1 vs. 41.4 %, respectively (p < 0.0001). IMRT for laryngeal and hypopharyngeal cancer minimizes late dysphagia without jeopardizing tumor control and outcome. (orig.) [German] Das Ziel dieser Studie war es, retrospektiv den Nutzen der intensitaetsmodulierten Strahlentherapie (IMRT) in der Behandlung von Patienten mit Plattenepithelkarzinom von Kehlkopf und Hypopharynx (LHSCC) zu bewerten und mit dem Outcome und den Spaetfolgen der 3-D-konformalen Strahlentherapie (3D-CRT) zu vergleichen. Insgesamt wurden zwischen Januar 2007 und Dezember 2012175 LHSCC-Patienten mit einer RT behandelt und in die Studie aufgenommen: 85 Patienten wurden mit 3D-CRT und 90 Patienten mit IMRT behandelt.Das onkologische Outcome wurde mittels Kaplan-Meier-Statistik ermittelt und Akut- und Spaettoxizitaeten anhand der CTCAE

Conformation radiotherapy with eccentric multi-leaves, (1)

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Obata, Yasunori; Sakuma, Sadayuki.

1986-01-01

In order to extend the application of the conformation radiotherapy, the eccentric multi-leaves are equipped with the linear accelerator. The information of the position of the collimators and the dose distribution of the eccentric conformation radiotherapy are calculated by the improved algorism of the treatment planning system. In simple cases, the dose distributions for the distant region from the rotational center are measured and compared with the calculated values. Both distributions are well coincided with the error of about 5 % in the high dose region and 10 % in the low dose region. In eccentric conformation radiotherapy, it is difficult to deliver the planned dose to the lesion. The dose increases with the distance of the target area from the rotational center. And the measured value and the calculated value are well coincided with 1 % error. So after getting the dose ratio of the rotational center to the target area, the calculated dose can be delivered to the rotational center. The advantages of the eccentric conformation radiotherapy are a good coincidence of target area and treated area, a partial shielding and a hollow out technique without absorber. The limitation of the movement of the collimator from center is 5 cm at 1 m SCD. (author)

Hippocampal sparing radiotherapy for glioblastoma patients: a planning study using volumetric modulated arc therapy

International Nuclear Information System (INIS)

Hofmaier, Jan; Kantz, Steffi; Söhn, Matthias; Dohm, Oliver S.; Bächle, Stefan; Alber, Markus; Parodi, Katia; Belka, Claus; Niyazi, Maximilian

2016-01-01

The purpose of this study is to investigate the potential to reduce exposure of the contralateral hippocampus in radiotherapy for glioblastoma using volumetric modulated arc therapy (VMAT). Datasets of 27 patients who had received 3D conformal radiotherapy (3D-CRT) for glioblastoma with a prescribed dose of 60Gy in fractions of 2Gy were included in this planning study. VMAT plans were optimized with the aim to reduce the dose to the contralateral hippocampus as much as possible without compromising other parameters. Hippocampal dose and treatment parameters were compared to the 3D-CRT plans using the Wilcoxon signed-rank test. The influence of tumour location and PTV size on the hippocampal dose was investigated with the Mann–Whitney-U-test and Spearman’s rank correlation coefficient. The median reduction of the contralateral hippocampus generalized equivalent uniform dose (gEUD) with VMAT was 36 % compared to the original 3D-CRT plans (p < 0.05). Other dose parameters were maintained or improved. The median V30Gy brain could be reduced by 17.9 % (p < 0.05). For VMAT, a parietal and a non-temporal tumour localisation as well as a larger PTV size were predictors for a higher hippocampal dose (p < 0.05). Using VMAT, a substantial reduction of the radiotherapy dose to the contralateral hippocampus for patients with glioblastoma is feasible without compromising other treatment parameters. For larger PTV sizes, less sparing can be achieved. Whether this approach is able to preserve the neurocognitive status without compromising the oncological outcome needs to be investigated in the setting of prospective clinical trials

Involved-Site Image-Guided Intensity Modulated Versus 3D Conformal Radiation Therapy in Early Stage Supradiaphragmatic Hodgkin Lymphoma

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Filippi, Andrea Riccardo, E-mail: andreariccardo.filippi@unito.it [Department of Oncology, University of Torino, Torino (Italy); Ciammella, Patrizia [Radiation Therapy Unit, Department of Oncology and Advanced Technology, ASMN Hospital IRCCS, Reggio Emilia (Italy); Piva, Cristina; Ragona, Riccardo [Department of Oncology, University of Torino, Torino (Italy); Botto, Barbara [Hematology, Città della Salute e della Scienza, Torino (Italy); Gavarotti, Paolo [Hematology, University of Torino and Città della Salute e della Scienza, Torino (Italy); Merli, Francesco [Hematology Unit, ASMN Hospital IRCCS, Reggio Emilia (Italy); Vitolo, Umberto [Hematology, Città della Salute e della Scienza, Torino (Italy); Iotti, Cinzia [Radiation Therapy Unit, Department of Oncology and Advanced Technology, ASMN Hospital IRCCS, Reggio Emilia (Italy); Ricardi, Umberto [Department of Oncology, University of Torino, Torino (Italy)

2014-06-01

Purpose: Image-guided intensity modulated radiation therapy (IG-IMRT) allows for margin reduction and highly conformal dose distribution, with consistent advantages in sparing of normal tissues. The purpose of this retrospective study was to compare involved-site IG-IMRT with involved-site 3D conformal RT (3D-CRT) in the treatment of early stage Hodgkin lymphoma (HL) involving the mediastinum, with efficacy and toxicity as primary clinical endpoints. Methods and Materials: We analyzed 90 stage IIA HL patients treated with either involved-site 3D-CRT or IG-IMRT between 2005 and 2012 in 2 different institutions. Inclusion criteria were favorable or unfavorable disease (according to European Organization for Research and Treatment of Cancer criteria), complete response after 3 to 4 cycles of an adriamycin- bleomycin-vinblastine-dacarbazine (ABVD) regimen plus 30 Gy as total radiation dose. Exclusion criteria were chemotherapy other than ABVD, partial response after ABVD, total radiation dose other than 30 Gy. Clinical endpoints were relapse-free survival (RFS) and acute toxicity. Results: Forty-nine patients were treated with 3D-CRT (54.4%) and 41 with IG-IMRT (45.6%). Median follow-up time was 54.2 months for 3D-CRT and 24.1 months for IG-IMRT. No differences in RFS were observed between the 2 groups, with 1 relapse each. Three-year RFS was 98.7% for 3D-CRT and 100% for IG-IMRT. Grade 2 toxicity events, mainly mucositis, were recorded in 32.7% of 3D-CRT patients (16 of 49) and in 9.8% of IG-IMRT patients (4 of 41). IG-IMRT was significantly associated with a lower incidence of grade 2 acute toxicity (P=.043). Conclusions: RFS rates at 3 years were extremely high in both groups, albeit the median follow-up time is different. Acute tolerance profiles were better for IG-IMRT than for 3D-CRT. Our preliminary results support the clinical safety and efficacy of advanced RT planning and delivery techniques in patients affected with early stage HL, achieving complete

Dosimetric analysis of the brachial plexus among patients with breast cancer treated with post-mastectomy radiotherapy to the ipsilateral supraclavicular area: report of 3 cases of radiation-induced brachial plexus neuropathy

International Nuclear Information System (INIS)

Wu, San-Gang; Huang, Si-Juan; Zhou, Juan; Sun, Jia-Yuan; Guo, Han; Li, Feng-Yan; Lin, Qin; Lin, Huan-Xin; He, Zhen-Yu

2014-01-01

The purpose of this study was to evaluate the brachial plexus (BP) dose of postmastectomy radiotherapy (PMRT) to the ipsilateral supraclavicular (ISCL) area, and report the characteristics of radiation-induced brachial plexus neuropathy (RIBPN). The BP dose of 31 patients who received adjuvant PMRT to the ISCL area and chest wall using three-dimensional conformal radiotherapy (3DCRT) and the records of 3 patients with RIBPN were retrospectively analyzed based on the standardized Radiation Therapy Oncology Group-endorsed guidelines. The total dose to the ISCL area and chest wall was 50 Gy in 25 fractions. Patients with a higher number of removed lymph nodes (RLNs) had a higher risk of RIBPN (hazard ratio [HR]: 1.189, 95% confidence interval [CI]: 1.005-1.406, p = 0.044). In 31 patients treated with 3DCRT, the mean dose to the BP without irradiation to the ISCL area was significantly less than that with irradiation to the ISCL area (0.97 ± 0.20 vs. 44.39 ± 4.13 Gy, t = 136.75, p <0.001). In the 3DCRT plans with irradiation to the ISCL area and chest wall, the maximum dose to the BP was negatively correlated with age (r = −0.40, p = 0.026), body mass index (BMI) (r = −0.44, p = 0.014), and body weight (r = −0.45, p = 0.011). Symptoms of the 3 patients with RIBPN occurred 37–65 months after radiotherapy, and included progressive upper extremity numbness, pain, and motor disturbance. After treatment, 1 patient was stable, and the other 2 patients’ symptoms worsened. The incidence of RIBPN was higher in patients with a higher number of RLNs after PMRT. The dose to the BP is primarily from irradiation of the ISCL area, and is higher in slim and young patients. Prevention should be the main focus of managing RIBPN, and the BP should be considered an organ-at-risk when designing a radiotherapy plan for the ISCL area

Potential for Improved Intelligence Quotient Using Volumetric Modulated Arc Therapy Compared With Conventional 3-Dimensional Conformal Radiation for Whole-Ventricular Radiation in Children

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Qi, X. Sharon; Stinauer, Michelle; Rogers, Brion; Madden, Jennifer R.; Wilkening, Greta N.; Liu, Arthur K.

2012-01-01

Purpose: To compare volumetric modulated arc therapy (VMAT) with 3-dimensional conformal radiation therapy (3D-CRT) in the treatment of localized intracranial germinoma. We modeled the effect of the dosimetric differences on intelligence quotient (IQ). Method and Materials: Ten children with intracranial germinomas were used for planning. The prescription doses were 23.4 Gy to the ventricles followed by 21.6 Gy to the tumor located in the pineal region. For each child, a 3D-CRT and full arc VMAT was generated. Coverage of the target was assessed by computing a conformity index and heterogeneity index. We also generated VMAT plans with explicit temporal lobe sparing and with smaller ventricular margin expansions. Mean dose to the temporal lobe was used to estimate IQ 5 years after completion of radiation, using a patient age of 10 years. Results: Compared with the 3D-CRT plan, VMAT improved conformality (conformity index 1.10 vs 1.85), with slightly higher heterogeneity (heterogeneity index 1.09 vs 1.06). The averaged mean doses for left and right temporal lobes were 31.3 and 31.7 Gy, respectively, for VMAT plans and 37.7 and 37.6 Gy for 3D-CRT plans. This difference in mean temporal lobe dose resulted in an estimated IQ difference of 3.1 points at 5 years after radiation therapy. When the temporal lobes were explicitly included in the VMAT optimization, the mean temporal lobe dose was reduced 5.6-5.7 Gy, resulting in an estimated IQ difference of an additional 3 points. Reducing the ventricular margin from 1.5 cm to 0.5 cm decreased mean temporal lobe dose 11.4-13.1 Gy, corresponding to an estimated increase in IQ of 7 points. Conclusion: For treatment of children with intracranial pure germinomas, VMAT compared with 3D-CRT provides increased conformality and reduces doses to normal tissue. This may result in improvements in IQ in these children.

Acute and late side-effects of conventional and conformal pelvic radiotherapy for cervical and endometrial cancer

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Izmajlowicz, B.; Komafel, J.

2010-01-01

Aim of the study. The purpose of this prospective study was to analyze and compare acute and late side-effects observed in patients with cervical and endometrial cancer treated with conventional 2-dimensional (2D) and conformal 3-dimensional (3D) pelvic radiotherapy. Patients and method. 50 patients treated with conventional pelvic radiotherapy and 50 patients treated with conformal pelvic radiotherapy at the Clinical Department of Gynecological Radiotherapy of the Lower Silesian Oncology Center between November 2004 and October 2005 were entered into a prospective study. We assessed Radiotherapy side-effects according to EORTCIRTOG, performance status according to the WHO, Body Mass Index and hematologic parameters during radiotherapy and one year after treatment. Results. Performance status acc. to the WHO was significantly better in the conformal arm. Anemia and nausea were more frequent in the conventional arm. In both the study groups acute gastrointestinal and genitourinary morbidity was more frequent than late morbidity and performance status was better after than before radiotherapy. Mean BMI was lower after radiotherapy than before treatment. Conclusions. Conformal pelvic radiotherapy in patients with cervical and endometrial cancer is less toxic than conventional pelvic radiotherapy which is also confirmed by the performance status. (authors)

Impact of radiation dose on achieving nadir PSA levels after 3-dimensional conformal radiotherapy for patients with localized prostate cancer

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Zelefsky, Michael J.; Leibel, Steven A.; Kelson, Suzanne; Fuks, Zvi

1996-01-01

Purpose: Several reports have documented the prognostic value of a post-irradiation nadir PSA of ≤1 ng/ml in prostatic cancer patients. The purpose of this study was to determine which pre-treatment and treatment-related variables impact upon achieving such nadir levels. Materials and Methods: Between January 1987 and June 1995, 740 patients with clinically localized prostate cancer were treated with 3-dimensional conformal radiotherapy (3D-CRT). 214 (29%) patients were treated with neo-adjuvant androgen ablation prior to therapy and were excluded from this analysis. Among the 526 evaluable patients, the clinical stage were as follows: T 1 C=128 (24%); T 2 A=76 (14%); T 2 B=116 (22%); T 2 C=99 (19%) and T 3 =107 (21%). The prescription dose to the planning target volume (PTV) was 64.8-68.4 Gy in 87 patients (17%); 70.2 Gy in 191 (36%); 75.6 Gy in 209 (40%) and 81 Gy in 39 (7%). The median pre-treatment PSA value was 11.2 ng/ml (range 0.3-114). The median follow-up was 20 months (range: 6-76 months). Results: 242 patients (46%) had PSA levels which declined to ≤1.0 ng/ml. The median time to a nadir level of ≤1.0 was 15.6 months (range: 1-43 months) from completion of 3D-CRT. 154 (29%) patients continued to show declining PSA levels within the first 2 years after therapy, and 130 patients (25%) failed to nadir at PSA levels of ≤1.0 ng/ml. Among patients with nadir PSA levels ≤1, the 3 year PSA relapse-free survival was 91% compared to 29% for patients with nadir PSA levels >1 ng/ml (p<0.0001). A Cox-regression analysis demonstrated that nadir PSA ≤1 was the strongest predictor of PSA relapse-free survival (p<0.001) followed by Gleason score ≤ 6 (p<0.001) and stage< T3 (p=0.004). Among patients who received doses of ≥75.6 Gy, the likelihood of achieving PSA nadir levels ≤1.0 at 24 and 36 months was 86% and 93%, respectively, compared to 74 and 80%, respectively, among those who received lower doses (p<0.001). Doses of ≥75.6 Gy was the strongest

Psa control for dose escalation with 3DCRT in the treatment of prostate cancer

International Nuclear Information System (INIS)

Alvarez Sosa, Amarilys; Rodriguez, Yaima; Perez Velasquez, Reytel

2009-01-01

In the detection of prostate cancer PSA carry out checks on patients between 40-50 years or more. The present work has as objective to establish the procedure 'in vivo' and i n vitro , based on ISO 9000, for assessment changes in PSA levels in patients who underwent scaling the dose through the 3D-CRT. The procedure provides the steps to follow from diagnostic evaluation to the completion of treatment with 3D-CRT. Finally This document is a valuable tool in assessing the effectiveness of treatment for prostate cancer with 3D-CRT. (author)

Investigation of normal tissue complication probabilities in prostate and partial breast irradiation radiotherapy techniques

International Nuclear Information System (INIS)

Bezak, E.; Takam, R.; Bensaleh, S.; Yeoh, E.; Marcu, L.

2011-01-01

Full text: Normal- Tissue-Complication Probabilities of rectum, bladder and urethra following various radiation techniques for prostate cancer were evaluated using the relative-seriality and Lyman models. NTCPs of lungs, heart and skin, their dependence on sourceposition, balloon-deformation were also investigated for HDR mammosite brachytherapy. The prostate treatment techniques included external three dimentional conformal-radiotherapy, Low-Dose-Rate brachytherapy (1-125), High-Dose-Rate brachytherapy (Ir-I92). Dose- Volume-Histograms of critical structures for prostate and breast radiotherapy, retrieved from corresponding treatment planning systems, were converted to Biological Effective Dose (BEffD)-based and Equivalent Dose(Deq)-based DVHs to account for differences in radiation delivery and fractionation schedule. Literature-based model parameters were used to calculate NTCPs. Hypofractionated 3D-CRT (2.75 Gy/fraction, total dose 55 Gy) NTCPs of rectum, bladder and urethra were less than those for standard fractionated 4-field 3D-CRT (2-Gy/fraction, 64 Gy) and dose-escalated 4- and 5-field 3D-CRT (74 Gy). Rectal and bladder NTCPs (5.2% and 6.6%) following the dose-escalated 4-field 3D-CRT (74 Gy) were the highest among analyzed techniques. The average NTCP for rectum and urethra were 0.6% and 24.7% for LDRBT and 0.5% and 11.2% for HDR-BT. For Mammosite, NTCP was estimated to be 0.1 %, 0.1 %, 1.2% and 3.5% for skin desquamation, erythema, telangiectasia and fibrosis respectively (the source positioned at the balloon centre). A 4 mm Mammosite-balloon deformation leads to overdosing of PTV regions by ∼40%, resulting in excessive skin dose and increased NTCP. Conclusions Prostate brachytherapy resulted in NTCPs lower compared to external beam techniques. Mammosite-brachytherapy resulted in no heart/lung complications regardless of balloon deformation. However, 4 mm deformation caused 0.6% increase in tissue fibrosis NTCP.

A survey on the state on the use of conformation radiotherapy units in Japan

International Nuclear Information System (INIS)

Tomaru, Teizo; Onai, Yoshio; Abe, Shunsuke

1985-01-01

A survey on the stage on the use of conformation radiotherapy units in Japan was performed by the Radiotherapy Equipments Committee of the Japanese Association for Radiotherapy Systems. The questionnaire was sent to 34 hospitals, which are all the hospitals equipped with these units, and 13 cancer and adult disease centers. The answers were collected from 42 hospitals, of which the 31 from formers and 11 from latters. In June, 1984, 27 conformation radiotherapy units (11 units with a pair of lower jaws and 16 units with multi-leaf collimators) were being used at 26 hospitals answered to questionnaire. During a month from May 16 to June 15 in 1984, conformation radiotherapy was performed at 10 hopsitals, and mean number of patients per day treated with these irradiation techniques was 3.7 +- 3.5. Fixed beam radiotherapy with irregular shape fields using multi-leaf collimators was also performed at 8 hospitals and mean number of patients per day treated with this fixed beam was 6.6 +- 3.9. Hollow-out irradiation technique was used at 4 hospitals, and 3.8 patients per day per hospital were treated with this technique. (author)

Treatment planning with protons for pediatric retinoblastoma, medulloblastoma, and pelvic sarcoma: How do protons compare with other conformal techniques?

International Nuclear Information System (INIS)

Lee, Catherine T.; Bilton, Stephen D.; Famiglietti, Robin M.; Riley, Beverly A.; Mahajan, Anita; Chang, Eric L.; Maor, Moshe H.; Woo, Shiao Y.; Cox, James D.; Smith, Alfred R.

2005-01-01

Purpose: To calculate treatment plans and compare the dose distributions and dose-volume histograms (DVHs) for photon three-dimensional conformal radiation therapy (3D-CRT), electron therapy, intensity-modulated radiation therapy (IMRT), and standard (nonintensity modulated) proton therapy in three pediatric disease sites. Methods and Materials: The tumor volumes from 8 patients (3 retinoblastomas, 2 medulloblastomas, and 3 pelvic sarcomas) were studied retrospectively to compare DVHs from proton therapy with 3D-CRT, electron therapy, and IMRT. In retinoblastoma, several planning techniques were analyzed: A single electron appositional beam was compared with a single 3D-CRT lateral beam, a 3D-CRT anterior beam paired with a lateral beam, IMRT, and protons. In medulloblastoma, three posterior fossa irradiation techniques were analyzed: 3D-CRT, IMRT, and protons. Craniospinal irradiation (which consisted of composite plans of both the posterior fossa and craniospinal components) was also evaluated, primarily comparing spinal irradiation using 3D-CRT electrons, 3D-CRT photons, and protons. Lastly, in pelvic sarcoma, 3D-CRT, IMRT, and proton plans were assessed. Results: In retinoblastoma, protons resulted in the best target coverage combined with the most orbital bone sparing (10% was the mean orbital bone volume irradiated at ≥5 Gy for protons vs. 25% for 3D-CRT electrons, 69% for IMRT, 41% for a single 3D lateral beam, 51% for a 3D anterolateral beam with a lens block, and 65% for a 3D anterolateral beam without a lens block). A single appositional electron field was the next best technique followed by other planning approaches. In medulloblastoma, for posterior fossa and craniospinal irradiation, protons resulted in the least dose to the cochlea (for only posterior fossa irradiation at ≥20 Gy, 34% was the mean cochlear volume irradiated for protons, 87% for IMRT, 89% for 3D-CRT) and hypothalamus-pituitary axis (for only posterior fossa irradiation at ≥10 Gy

Metallic stent and stereotactic conformal radiotherapy for hilar cholangiocarcinoma

International Nuclear Information System (INIS)

Li Yu; Wang Ning; Tian Qihe; Guo Zhanwen; Zhang Haibo; Song Liyan

2005-01-01

Objective: To evaluate the effect of metallic stent combined with stereotactic conformal radiotherapy (SCRT) for hilar cholangiocarcinoma. Methods: Fifty-four patients with hilar cholangiocarcinoma were analyzed, including 31 treated with stent plus stereotactic conformal radiotherapy (combined group) and 23 with metallic stent alone (control group). Results: The mean survival time of combined group was 11.1 ± 4.6 months, compared with 5.1 ± 2.8 months of the control group, giving a significant difference between the two groups (P<0.01). Conclusion: The combination of metallic stent and stereotactic conformal radiotherapy is more effective than metallic stent alone for unresectable hilar cholangiocarcinoma. (authors)

Critical dose and toxicity index of organs at risk in radiotherapy: Analyzing the calculated effects of modified dose fractionation in non–small cell lung cancer

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Pedicini, Piernicola, E-mail: ppiern@libero.it [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Strigari, Lidia [Laboratory of Medical Physics and Expert Systems, Regina Elena National Cancer Institute, Rome (Italy); Benassi, Marcello [Service of Medical Physics, Scientific Institute of Tumours of Romagna I.R.S.T., Meldola (Italy); Caivano, Rocchina [Service of Medical Physics, I.R.C.C.S. Regional Cancer Hospital C.R.O.B, Rionero in Vulture (Italy); Fiorentino, Alba [U.O. of Radiotherapy, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Nappi, Antonio [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy); Salvatore, Marco [U.O. of Nuclear Medicine, I.R.C.C.S. SDN Foundation, Naples (Italy); Storto, Giovanni [U.O. of Nuclear Medicine, I.R.C.C.S. Regional Cancer Hospital C.R.O.B., Rionero in Vulture (Italy)

2014-04-01

To increase the efficacy of radiotherapy for non–small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new “toxicity index” (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volume histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V{sub 20} in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC.

Analysis of the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy

Directory of Open Access Journals (Sweden)

Song-Lin Wang

2017-04-01

Full Text Available Objective: To explore the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy. Methods: A total of 84 patients who were admitted in our hospital after modified radical mastectomy were included in the study and divided into the conventional radiotherapy group (n=42 and the three-dimensional conformal radiotherapy group (n=42 according to different radiotherapy methods. The patients in the conventional radiotherapy group were given conventional radiotherapy of chest wall and clavicular field, while the patients in the three-dimensional conformal radiotherapy group were given three-dimensional conformal radiotherapy. The serum tumor markers and peripheral blood T lymphocyte subsets 6-8 weeks after treatment in the two groups were detected. The clinical efficacy, and toxic and side effects in the two groups were evaluated. Results: The serum CA15-3, CA125, CEA, and CK19 levels after treatment in the two groups were significantly reduced when compared with before treatment, CD3 +,CD4 +, and CD4 +/CD8 + were significantly elevated, while CD8 + was significantly reduced when compared with before treatment, but the comparison of the above indicators between the two groups was not statistically significant. The occurrence rate of radioactive skin damage and pneumonia after treatment in the conventional radiotherapy group was significantly higher than that in the three-dimensional conformal radiotherapy group. Conclusions: The two kinds of radiotherapy schemes have an equal efficacy, but the toxic and side effects of three-dimensional conformal radiotherapy are significantly lower than those by the conventional radiotherapy, with a certain advantage.

Three-dimensional conformal radiotherapy with concurrent chemotherapy for postoperative recurrence of esophageal squamous cell carcinoma: clinical efficacy and failure pattern

International Nuclear Information System (INIS)

Bao, Yong; Rong, TieHua; Li, Qun; Liu, Hui; Liu, ShiLiang; Zhou, QiChao; Cai, PeiQiang; Anfossi, Simone; Li, QiaoQiao; Hu, YongHong; Liu, MengZhong; Fu, JianHua

2013-01-01

To assess the therapeutic outcome and failure pattern of three-dimensional conformal radiotherapy (3D-CRT)-based concurrent chemoradiotherapy (CCRT) for recurrence of esophageal squamous cell carcinoma (SCC) after radical surgery. Treatment outcome and failure pattern were retrospectively evaluated in 83 patients with localized cervical and thoracic recurrences after radical surgery for thoracic esophageal SCC. All patients were treated with 3DCRT-based CCRT (median radiation dose 60 Gy), in which 39 received concurrent cisplatin plus 5-fluorouracil (PF), and 44 received concurrent docetaxel plus cisplatin (TP). Treatment response was evaluated at 1–3 months after CCRT. With a median follow-up of 34 months (range, 2–116 months), the 3-year overall survival (OS) of all the patients was 51.8% and the median OS time was 43.0 months. The overall tumor response rate was 75.9% (63/83), with a complete remission (CR) rate of 44.6% (37/83). In univariate analysis, tumor response after CCRT (p = 0.000), recurrence site (p = 0.028) and concurrent chemotherapy (p = 0.090) showed a trend favoring better OS. Multivariate analysis revealed that tumor response after CCRT (p = 0.000) and concurrent chemotherapy (p = 0.010) were independent predictors of OS. Forty-seven patients had progressive diseases after CCRT, 27 had local failure (27/47, 57.4%), 18 had distant metastasis (18/47, 38.3%) and 2 had both local and distant failures (2/47, 4.3%). 3DCRT-based CCRT is effective in postoperatively recurrent esophageal SCC. Patients that obtained complete remission after CCRT appeared to achieve long-term OS and might benefit from concurrent TP regimen. Local and distant failures remained high and prospective studies are needed to validate these factors

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

International Nuclear Information System (INIS)

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.

Three dimensional conformal postoperative radiotherapy for ...

African Journals Online (AJOL)

Azza Helal

2013-06-17

Jun 17, 2013 ... during postoperative 3DCRT treatment of parotid gland cancer patients. ... contralateral parotid, oral cavity, cochlea, spinal cord, brain stem, eyes, lenses and ... xerostomia, dry ear, ear infections, hearing deficits and ipsilat-.

Conventional (2D) Versus Conformal (3D) Techniques in Radiotherapy for Malignant Pediatric Tumors: Dosimetric Perspectives

International Nuclear Information System (INIS)

Ahmad, N.; Attia, G.; Radwan, A.; El-Badawy, S.; El-Ghoneimy, E.

2009-01-01

Objectives: In pediatric radiotherapy, the enhanced radiosensitivity of the developing tissues combined with the high overall survival, raise the possibility of late complications. The present study aims at comparing two dimensional (2D) and three dimensional (3D) planning regarding dose homogeneity within target volume and dose to organs at risk (OARs) to demonstrate the efficacy of 3D in decreasing dose to normal tissue. Material and Methods: Thirty pediatric patients (18 years or less) with different pediatric tumors were planned using 2D and 3D plans. All were CT scanned after proper positioning and immobilization. Structures were contoured; including the planning target volume (PTV) and organs at risk (OARs). Conformal beams were designed and dose distribution analysis was edited to provide the best dose coverage to the PTV while sparing OARs using dose volume histograms (DVHs) of outlined structures. For the same PTVs conventional plans were created using the conventional simulator data (2-4 coplanar fields). Conventional and 3D plans coverage and distribution were compared using the term of V95% (volume of PTV receiving 95% of the prescribed dose), V107% (volume of PTV receiving 107% of the prescribed dose), and conformity index (CI) (volume receiving 90% of the prescribed dose/PTV). Doses received by OARs were compared in terms of mean dose. In children treated for brain lesions, OAR volume received 90% of the dose (V 90%) and OAR score were calculated. Results: The PTV coverage showed no statistical difference between 2D and 3D radiotherapy in terms of V95% or V107%. However, there was more conformity in 3D planning with CI 1.43 rather than conventional planning with CI 1.86 (p-value <0.001). Regarding OARs, 3D planning shows large gain in healthy tissue sparing. There was no statistical difference in mean dose received by each OAR. However, for brain cases, brain stem mean dose and brain V 90% showed better sparing in 3D planning (brain stem mean dose was

Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

OpenAIRE

Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham

2013-01-01

Introduction Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation ...

On-line estimations of delivered radiation doses in three-dimensional conformal radiotherapy treatments of carcinoma uterine cervix patients in linear accelerator.

Science.gov (United States)

Putha, Suman Kumar; Saxena, P U; Banerjee, S; Srinivas, Challapalli; Vadhiraja, B M; Ravichandran, Ramamoorthy; Joan, Mary; Pai, K Dinesh

2016-01-01

Transmission of radiation fluence through patient's body has a correlation to the planned target dose. A method to estimate the delivered dose to target volumes was standardized using a beam level 0.6 cc ionization chamber (IC) positioned at electronic portal imaging device (EPID) plane from the measured transit signal (S t ) in patients with cancer of uterine cervix treated with three-dimensional conformal radiotherapy (3DCRT). The IC with buildup cap was mounted on linear accelerator EPID frame with fixed source to chamber distance of 146.3 cm, using a locally fabricated mount. S t s were obtained for different water phantom thicknesses and radiation field sizes which were then used to generate a calibration table against calculated midplane doses at isocenter (D iso,TPS ), derived from the treatment planning system. A code was developed using MATLAB software which was used to estimate the in vivo dose at isocenter (D iso,Transit ) from the measured S t s. A locally fabricated pelvic phantom validated the estimations of D iso,Transit before implementing this method on actual patients. On-line dose estimations were made (3 times during treatment for each patient) in 24 patients. The D iso,Transit agreement with D iso,TPS in phantom was within 1.7% and the mean percentage deviation with standard deviation is -1.37% ±2.03% ( n = 72) observed in patients. Estimated in vivo dose at isocenter with this method provides a good agreement with planned ones which can be implemented as part of quality assurance in pelvic sites treated with simple techniques, for example, 3DCRT where there is a need for documentation of planned dose delivery.

Acute morbidity reduction using 3DCRT for prostate carcinoma; a randomised phase III study

International Nuclear Information System (INIS)

Koper, P.; Putten, W. van; Stroom, J.; Korevaar, G.; Heijmen, B.; Wijnmaalen, A.; Jansen, P.; Hanssens, P.; Griep, C.; Krol, A.; Samson, M.; Levendag, P.

1997-01-01

observed. In the QOL questionnaire analysis complaints were judged to be moderate/severe in resp 30%(conventional) vs 28%(conformal) for intestinal symptoms and 21%(conventional) vs 23% (conformal) for urological symptoms. The expected moderate reduction in exposed volume is diluted by a wide range of anatomical variations. For the bladder a trend for (dose) volume effect is observed. For the rectosigmoid however no relation for toxicity and volume exposed was found. A higher volume exposed is not translated in a increase of toxicity (grade 0 60%, grade I 57% and grade II 57% rectosigmoid volume exposed to doses >90% TD). Conclusions: 1. The randomised phase III study didn't show a statistical significant reduction in acute rectosigmoid and bladder toxicity. The reduction in intestinal morbidity (p=0.02) is mainly caused by reduced anal toxicity for 3DCRT. 2. The CTV-PTV margin of 10 mm will only modestly reduce the volumes exposed. The DVH difference is however further diluted by large anatomical variation. 3. In the preliminary DVH analysis for the first 100 patients a trend for a (dose) volume effect relationship is found for bladder. For rectosigmoid no (dose) volume effect relationship was found. This might be due to the dose level (66 Gy) and the 10 mm CTV-PTV 3D-margins. An extended DVH analysis will be presented

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.

Daily-diary evaluated side-effects of conformal versus conventional prostatic cancer radiotherapy technique

International Nuclear Information System (INIS)

Widmark, A.; Fransson, P.; Franzen, L.; Littbrand, B.; Henriksson, R.

1997-01-01

Conventional 4-field box radiotherapy technique induces high morbidity for patients with localized prostatic cancer. Using a patient daily diary, the present study compared side-effects after conventional radiotherapy with conformal radiotherapy for prostate cancer. Fifty-eight patients treated with the conventional technique (with or without sucralfate) were compared with 72 patients treated with conformal technique. The patient groups were compared with an age-matched control population. Patients treated with conformal technique were also evaluated regarding acute and late urinary problems. Results showed that patients treated with conformal technique reported significantly fewer side-effects as compared with conventional technique. Patients treated with sucralfate also showed slightly decreased intestinal morbidity in comparison to non-sucralfate group. Acute and late morbidity evaluated by the patients was decreased after conformal radiotherapy as compared with the conventional technique. Sucralfate may be of value if conformal radiotherapy is used for dose escalation in prostatic cancer patients. (orig.)

Conformal radiotherapy using multileaf collimation: quality assurance and in vivo dosimetry

Energy Technology Data Exchange (ETDEWEB)

Aletti, P [Centre A. Vautrin, Nancy (France)

1995-12-01

The application of quality assurance principles in three dimensional conformal therapy is discussed.Critical requirements in three dimensional radiotherapy are the patient immobilization, the location, and the delivered dose. General recommendations with respect to the equipment for conformal radiotherapy and personnel are made.

Conformal radiotherapy using multileaf collimation: quality assurance and in vivo dosimetry

International Nuclear Information System (INIS)

Aletti, P.

1995-01-01

The application of quality assurance principles in three dimensional conformal therapy is discussed.Critical requirements in three dimensional radiotherapy are the patient immobilization, the location, and the delivered dose. General recommendations with respect to the equipment for conformal radiotherapy and personnel are made

A potential to reduce pulmonary toxicity: The use of perfusion SPECT with IMRT for functional lung avoidance in radiotherapy of non-small cell lung cancer

International Nuclear Information System (INIS)

Lavrenkov, Konstantin; Christian, Judith A.; Partridge, Mike; Niotsikou, Elena; Cook, Gary; Parker, Michelle; Bedford, James L.; Brada, Michael

2007-01-01

Background and purpose: The study aimed to examine specific avoidance of functional lung (FL) defined by a single photon emission computerized tomography (SPECT) lung perfusion scan, using intensity modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3-DCRT) in patients with non-small cell lung cancer (NSCLC). Materials and methods: Patients with NSCLC underwent planning computerized tomography (CT) and lung perfusion SPECT scan in the treatment position using fiducial markers to allow co-registration in the treatment planning system. Radiotherapy (RT) volumes were delineated on the CT scan. FL was defined using co-registered SPECT images. Two inverse coplanar RT plans were generated for each patient: 4-field 3-DCRT and 5-field step-and-shoot IMRT. 3-DCRT plans were created using automated AutoPlan optimisation software, and IMRT plans were generated employing Pinnacle 3 treatment planning system (Philips Radiation Oncology Systems). All plans were prescribed to 64 Gy in 32 fractions using data for the 6 MV beam from an Elekta linear accelerator. The objectives for both plans were to minimize the volume of FL irradiated to 20 Gy (fV 20 ) and dose variation within the planning target volume (PTV). A spinal cord dose was constrained to 46 Gy. Volume of PTV receiving 90% of the prescribed dose (PTV 90 ), fV 20 , and functional mean lung dose (fMLD) were recorded. The PTV 90 /fV 20 ratio was used to account for variations in both measures, where a higher value represented a better plan. Results: Thirty-four RT plans of 17 patients with stage I-IIIB NSCLC suitable for radical RT were analysed. In 6 patients with stage I-II disease there was no improvement in PTV 90 , fV 20 , PTV/fV 20 ratio and fMLD using IMRT compared to 3-DCRT. In 11 patients with stage IIIA-B disease, the PTV was equally well covered with IMRT and 3-DCRT plans, with IMRT producing better PTV 90 /fV 20 ratio (mean ratio - 7.2 vs. 5.3, respectively, p = 0.001) and reduced f

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)

Dose-response relationship in local radiotherapy for hepatocellular carcinoma

International Nuclear Information System (INIS)

Park, Hee Chul; Seong, Jinsil; Han, Kwang Hyub; Chon, Chae Yoon; Moon, Young Myoung; Suh, Chang Ok

2002-01-01

Purpose: Dose escalation using three-dimensional conformal radiotherapy (3D-CRT) is based on the hypothesis that increasing the dose can enhance tumor control. This study aimed to determine whether a dose-response relationship exists in local radiotherapy for primary hepatocellular carcinoma (HCC). Methods and Materials: One hundred fifty-eight patients were enrolled in the present study between January 1992 and March 2000. The exclusion criteria included the presence of an extrahepatic metastasis, liver cirrhosis of Child class C, tumors occupying more than two-thirds of the entire liver, and a performance status on the Eastern Cooperative Oncology Group scale of more than 3. Radiotherapy was given to the field, including the tumor, with generous margin using 6- or 10-MV X-rays. The mean radiation dose was 48.2 ± 7.9 Gy in daily 1.8-Gy fractions. The tumor response was assessed based on diagnostic radiologic examinations, including a computed tomography scan, magnetic resonance imaging, and hepatic artery angiography 4-8 weeks after the completion of treatment. Liver toxicity and gastrointestinal complications were evaluated. Results: An objective response was observed in 106 of 158 (67.1%) patients. Statistical analysis revealed that the total dose was the most significant factor associated with the tumor response. The response rates in patients treated with doses 50 Gy were 29.2%, 68.6%, and 77.1%, respectively. Survivals at 1 and 2 years after radiotherapy were 41.8% and 19.9%, respectively, with a median survival time of 10 months. The rate of liver toxicity according to the doses 50 Gy was 4.2%, 5.9%, and 8.4%, respectively, and the rate of gastrointestinal complications was 4.2%, 9.9%, and 13.2%, respectively. Conclusions: The present study showed the existence of a dose-response relationship in local radiotherapy for primary HCC. Only the radiation dose was a significant factor for predicting an objective response. The results of this study showed that 3D-CRT

Potential risk factors for jaw osteoradionecrosis after radiotherapy for head and neck cancer

International Nuclear Information System (INIS)

Kuhnt, Thomas; Stang, Andreas; Wienke, Andreas; Vordermark, Dirk; Schweyen, Ramona; Hey, Jeremias

2016-01-01

To identify potential risk factors for the development of jaw osteoradionecrosis (ORN) after 3D-conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) among patients with newly diagnosed head and neck cancer. This study included 776 patients who underwent 3D-CRT or IMRT for head and neck cancer at the Department of Radiotherapy at the University Hospital Halle-Wittenberg between 2003 and 2013. Sex, dental status prior to radiotherapy, tumor site, bone surgery during tumor resection, concomitant chemotherapy, and the development of advanced ORN were documented for each patient. ORN was classified as grade 3, 4, or 5 according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer classification or grade 3 or 4 according to the late effects in normal tissues/subjective, objective, management, and analytic scale. The cumulative incidence of ORN was estimated. Cox regression analysis was used to identify prognostic risk factors for the development of ORN. Fifty-one patients developed advanced ORN (relative frequency 6.6 %, cumulative incidence 12.4 %). The highest risk was found in patients who had undergone primary bone surgery during tumor resection (hazard ratio [HR] = 5.87; 95 % confidence interval [CI]: 3.09–11.19) and in patients with tumors located in the oral cavity (HR = 4.69; 95 % CI: 1.33–16.52). Sex, dentition (dentulous vs. edentulous), and chemotherapy had no clinically relevant influence. In contrast to most previous studies, we noted a low cumulative incidence of advanced ORN. Patients with tumors located in the oral cavity and those who undergo bone surgery during tumor resection prior to RT may be considered a high-risk group for the development of ORN

Conformal radiotherapy for 6 cases of bile duct carcinoma

International Nuclear Information System (INIS)

Kawasaki, Yoshiyuki; Suzuki, Takashi; Sugahara, Shinji

1998-01-01

Authors performed the conformal radiotherapy using the multileaf collimator for inoperable patients with bile duct carcinoma and examined the usefulness of this treatment. Forty one patients were examined, whose age was from 45 to 80 years (mean: 69.5 years), and whose ratio of men to women was 1 to 1.6. Patients in Group I (palliative irradiation, 30 cases) received bilateral irradiation using the linac with 4 MV-x-ray of total 50.0 Gy (2.0 Gy a dose, 5 times a week), those in Group II (palliative irradiation, 5 cases) using the microtron with 10 MV-x-ray of total 50.0 Gy (2.0 Gy a dose, 5 times a week). And those in Group III (radial irradiation, 6 cases) were first irradiated using the microtron with total 40.0 Gy (2.0 Gy a dose, 5 times a week) and secondly by the conformal radiotherapy with total 20.0 Gy (2.0 Gy a dose, 5 times a week). Patients in Group III were irradiated with total 60.0 Gy. Patients in all Groups showed mild side-effects including nausea and vomiting. And patients in Group III, who were irradiated 10 Gy more than other Group, showed no severe side-effects as alimentary bleeding, liver function disorders and cholangitis. In Group I, one year survivors were 3 (10.0%) and two years survivors were none. The median survival month was 7.2 months. In Group II, one year survivor was 1 (20.0%) and two years survivors were none. The median survival month was 8.1 months. In Group III, one year survivors were 2 (33.3%), and two years survivors were 2 (33.3%). The median survival month was 11.2 months. Two patients are survival at present (March, 1998), 2 years and 10 months, and 2 years and 9 months, respectively. The conformal radiotherapy gave better results than the ordinary radiotherapy. (K.H.)

三维适形放疗与调强放疗治疗原发性肝癌伴门静脉癌栓的剂量学比较

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ZHOU Yuanyuan

2014-03-01

Full Text Available ObjectiveTo compare three-dimensional conformal radiotherapy (3DCRT and intensity-modulated radiotherapy (IMRT in terms of their advantages of disadvantages in the treatment of primary hepatocellular carcinoma (PHC with portal vein tumor thrombus (PVTT. MethodsTwenty patients with PHC accompanied by PVTT were enrolled in this study. Each patient underwent 3DCRT and IMRT with a prescribed dose of 40 Gy/ 20 fractions. The parameters included the conformity index (CI, homogeneity index (HI, mean dose (Dmean, minimum dose (Dmin, maximum dose (Dmax, V95%, V100%, and V105% for planning target volume (PTV, the number of monitor units (MUs for evaluating planning efficiency, and Dmean, Dmax, and Dmin for the organs at risk (OAR. The percentage of the normal liver volume receiving ≥30, ＞20, ＞10, and ＞5 Gy (V30 Gy, V20 Gy, V10 Gy, and V5 Gy, respectively were calculated to determine liver toxicity. The two radiotherapy regimens were compared in terms of the dosimetric parameters for PTV and OAR, as well as number of MUs. ResultsIMRT had significantly higher Dmin, Dmean, V95%, and V100% and significantly better HI and CI compared with 3DCRT (P＜0.05. The liver V30 Gy and V20 Gy were 33.55±5.67 and 44.24±6.17, respectively, for 3DCRT, versus 2941±267 and 41.28±4.59 for IMRT (P=0.001; P=0.021. There were no significant differences in liver V10 Gy, liver V5 Gy, stomach Dmax, small intestine Dmax, spinal cord Dmax, kidney Dmax, and kidney V20 Gy between IMRT and 3DCRT. The number of MUs was 303.7±35.8 for 3DCRT and 377.4±33.2 for IMRT (P=0.000. ConclusionIMRT provides higher tumor coverage, homogeneity, and conformity, as well as better normal liver tissue sparing, as compared with 3DCRT. However, IMRT is not superior to 3DCRT in terms of treatment efficiency.

Clinical Studies on conformal radiotherapy combined with epidermal ...

African Journals Online (AJOL)

in second-line treatment of non-small cell lung cancer ... receptor-tyrosine kinase inhibitor (EGFR-TKI) in the second-line treatment of non-small cell ... were divided into two groups: 106 patients were treated with conformal ... Conformal radiotherapy, Targeted therapy, Survival rate .... regression model was used for survival.

Evaluation of homogeneity and dose conformity in IMRT planning in prostate radiotherapy

International Nuclear Information System (INIS)

Lopes, Juliane S.; Leidens, Matheus; Estacio, Daniela R.; Razera, Ricardo A.Z.; Streck, Elaine E.; Silva, Ana M.M. da

2015-01-01

The goal of this study was to evaluate the dose distribution homogeneity and conformity of radiation therapy plans of prostate cancer using IMRT. Data from 34 treatment plans of Hospital Sao Lucas of PUCRS, where those plans were executed, were retrospectively analyzed. All of them were done with 6MV X-rays from a linear accelerator CLINAC IX, and the prescription doses varied between 60 and 74 Gy. Analyses showing the homogeneity and conformity indices for the dose distribution of those plans were made. During these analyses, some comparisons with the traditional radiation therapy planning technic, the 3D-CRT, were discussed. The results showed that there is no correlation between the prescribed dose and the homogeneity and conformity indices, indicating that IMRT works very well even for higher doses. Furthermore, a comparison between the results obtained and the recommendations of ICRU 83 was carried out. It has also been observed that the indices were really close to the ideal values. 82.4% of the cases showed a difference below 5% of the ideal value for the index of conformity, and 88.2% showed a difference below 10% for the homogeneity index. Concluding, it is possible to confirm the quality of the analyzed radiation therapy plans of prostate cancer using IMRT. (author)

3DCRT for posterior fossa: Sparing of surrounding organs at risk

African Journals Online (AJOL)

Azza Helal

2013-06-25

Jun 25, 2013 ... spinal cord, thyroid gland, pharynx, parotid glands and mandible using three different 3DCRT ... Methods: Ten patients underwent CT simulation for treatment .... structures such as the developing brain, bone, thyroid gland,.

Conformal Radiotherapy in the Treatment of Advanced Juvenile Nasopharyngeal Angiofibroma With Intracranial Extension: An Institutional Experience

International Nuclear Information System (INIS)

Chakraborty, Santam; Ghoshal, Sushmita; Patil, Vijay Maruti; Oinam, Arun Singh; Sharma, Suresh C.

2011-01-01

Purpose: To describe the results of conformal radiotherapy in advanced juvenile nasopharyngeal angiofibroma in a tertiary care institution. Methods and Materials: Retrospective chart review was conducted for 8 patients treated with conformal radiotherapy between 2006 and 2009. The median follow-up was 17 months. All patients had Stage IIIB disease with intracranial extension. Radiotherapy was considered as treatment because patients were deemed inoperable owing to extensive intracranial/intraorbital extension or proximity to optic nerve. All but 1 patient were treated with intensity-modulated radiotherapy using seven coplanar fields. Median (range) dose prescribed was 39.6 (30-46) Gy. Actuarial analysis of local control and descriptive analysis of toxicity profile was conducted. Results: Despite the large and complex target volume (median planning target volume, 292 cm 3 ), intensity-modulated radiotherapy achieved conformal dose distributions (median van't Reit index, 0.66). Significant sparing of the surrounding organs at risk was obtained. No significant Grade 3/4 toxicities were experienced during or after treatment. Actual local control at 2 years was 87.5%. One patient died 1 month after radiotherapy secondary to massive epistaxis. The remaining 7 patients had progressive resolution of disease and were symptom-free at last follow-up. Persistent rhinitis was the only significant toxicity, seen in 1 patient. Conclusions: Conformal radiotherapy results in good local control with minimal acute and late side effects in juvenile nasopharyngeal angiofibromas, even in the presence of advanced disease.

Risk factors of radiation-induced liver disease after three-dimensional conformal radiotherapy for primary liver carcinoma

International Nuclear Information System (INIS)

Liang Shixiong; Zhu Xiaodong; Lu Haijie; Pan Chaoyang; Huang Qifang; Li Fuxiang; Wang Anyu; Liang Guoliang; Fu Xiaolong

2005-01-01

Objective: To identify the risk factors of radiation-induced liver disease (RILD) after three-dimensional radiotherapy (3DCRT) for primary liver carcinoma (PLC) and the dosimetric threshold of RILD. Methods: Between April 1999 and August 2003, 128 PLC patients who were treated with 3DCRT received a mean dose of 53.6 ± 6.6 Gy with a 4-8 Gy/f, 3f/w, qod regimen. The relation between RILD and the possible clinical factors, such as gender, age, UICC/ AJCC T stage, GTV, HBV status, PTV, TACE, Child-Pugh grade of liver cirrhosis, BED calculated by LQ model and fraction size were analyzed. Among 84 patients who had full dose- volume histogram (DVH) data, the relation between RILD and dosimetric parameters were analyzed. Results: Nineteen patients (14.8%) developed RILD. It was found that T stage, GTV, PTV, Child-Pugh grade of liver cirrhosis and the acute hepatic toxicity proposed by common toxicity criteria version 2.0 (CTC2.0) were correlated with RILD (P=0.024, 0.002, 0.001, 0.000, 0.000, respectively). Multivariate analysis showed that only the Child-Pugh grade of liver cirrhosis was independent factor (P=0.000). The mean liver dose was significantly higher in patients with RILD (P=0.027). In patients with Child-Pugh grade A, V5 (percentage of normal liver volume with radiation dose > 5 Gy), V 10 and V 20 ≤81%, 69% and 42%, mean liver dose ≤28 Gy, RILD was not observed, whereas in patients with Child-Pugh grade B, the possibility of developing RILD was 53.3%(8/15). Conclusions: Comprehensive consideration of T stage, GTV, PTV and Child-Pugh grade of liver cirrhosis, especially the Child-Pugh grade of liver cirrhosis, when planning 3DCRT for PLC, may lower the incidence of RILD. (authors)

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.

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

International Nuclear Information System (INIS)

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.

Science.gov (United States)

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.

Conformal radiotherapy: a glossary

International Nuclear Information System (INIS)

Dubray, B.; Giraud, P.; Beaudre, A.

1999-01-01

Most of the concepts and terms related to conformal radiotherapy were produced by English-speaking authors and eventually validated by international groups of experts, whose working language was also English. Therefore, a significant part of this literature is poorly accessible to the French-speaking radiation oncology community. The present paper gathers the 'official' definitions already published in French, along with propositions for the remaining terms which should be submitted to a more formal and representative validation process. (author)

Effective avoidance of a functional spect-perfused lung using intensity modulated radiotherapy (IMRT) for non-small cell lung cancer (NSCLC): An update of a planning study

International Nuclear Information System (INIS)

Lavrenkov, Konstantin; Singh, Shalini; Christian, Judith A.; Partridge, Mike; Nioutsikou, Elena; Cook, Gary; Bedford, James L.; Brada, Michael

2009-01-01

IMRT and 3-dimensional conformal radiotherapy (3-DCRT) plans of 25 patients with non-small cell lung (NSCLC) were compared in terms of planning target volume (PTV) coverage and sparing of functional lung (FL) defined by a SPECT perfusion scan. IMRT resulted in significant reduction of functional V 20 and mean lung dose in stage III patients with inhomogeneous hypoperfusion. If the dose to FL is shown to be the determinant of lung toxicity, IMRT would allow for effective dose escalation by specific avoidance of functional lung.

Extracranial stereotactic radiotherapy: Evaluation of PTV coverage and dose conformity

International Nuclear Information System (INIS)

Haedinger, U.; Thiele, W.; Wulf, J.

2002-01-01

During the past few years the concept of cranial sterotactic radiotherapy has been successfully extended to extracranial tumoral targets. In our department, hypofractionated treatment of tumours in lung, liver, abdomen, and pelvis is performed in the Stereotactic Body Frame (ELEKTA Instrument AB) since 1997. We present the evaluation of 63 consecutively treated targets (22 lung, 21 liver, 20 abdomen/pelvis) in 58 patients with respect to dose coverage of the planning target volume (PTV) as well as conformity of the dose distribution. The mean PTV coverage was found to be 96.3%±2.3% (lung), 95.0%±4.5% (liver), and 92.1%±5.2% (abdomen/pelvis). For the so-called conformation number we obtained values of 0.73±0.09 (lung), 0.77±0.10 (liver), and 0.70±0.08 (abdomen/pelvis). The results show that highly conformal treatment techniques can be applied also in extracranial stereotactic radiotherapy. This is primarily due to the relatively simple geometrical shape of most of the targets. Especially lung and liver targets turned out to be approximately spherically/cylindrically shaped, so that the dose distribution can be easily tailored by rotational fields. (orig.) [de

Comparison and Limitations of DVH-Based NTCP Models Derived From 3D-CRT and IMRT Data for Prediction of Gastrointestinal Toxicities in Prostate Cancer Patients by Using Propensity Score Matched Pair Analysis

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Troeller, Almut [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Department of Radiotherapy and Radiation Oncology, Ludwig-Maximilians-Universität, Munich (Germany); Yan, Di, E-mail: dyan@beaumont.edu [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Marina, Ovidiu; Schulze, Derek [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Alber, Markus [Department of Oncology, Aarhus University Hospital, Aarhus (Denmark); Parodi, Katia [Department of Medical Physics, Ludwig-Maximilians-Universität, Munich (Germany); Belka, Claus; Söhn, Matthias [Department of Radiotherapy and Radiation Oncology, Ludwig-Maximilians-Universität, Munich (Germany)

2015-02-01

Purpose: This study compared normal tissue complication probability (NTCP) modeling of chronic gastrointestinal toxicities following prostate cancer treatment for 2 treatment modalities. Possible factors causing discrepancies in optimal NTCP model parameters between 3-dimensional conformal radiation therapy (3D-CRT) and intensity modulated RT (IMRT) were analyzed and discussed, including the impact of patient characteristics, image guidance, toxicity scoring bias, and NTCP model limitations. Methods and Materials: Rectal wall dose-volume histograms of 1115 patients treated for prostate cancer under an adaptive radiation therapy protocol were used to model gastrointestinal toxicity grade ≥2 (according to Common Terminology Criteria for Adverse Events). A total of 457 patients were treated with 3D-CRT and 658 with IMRT. 3D-CRT patients were matched to IMRT patients based on various patient characteristics, using a propensity score–based algorithm. Parameters of the Lyman equivalent uniform dose and cut-off dose logistic regression NTCP models were estimated for the 2 matched treatment modalities and the combined group. Results: After they were matched, the 3D-CRT and IMRT groups contained 275 and 550 patients with a large discrepancy of 28.7% versus 7.8% toxicities, respectively (P<.001). For both NTCP models, optimal parameters found for the 3D-CRT groups did not fit the IMRT patients well and vice versa. Models developed for the combined data overestimated NTCP for the IMRT patients and underestimated NTCP for the 3D-CRT group. Conclusions: Our analysis did not reveal a single definitive cause for discrepancies of model parameters between 3D-CRT and IMRT. Patient characteristics and bias in toxicity scoring, as well as image guidance alone, are unlikely causes of the large discrepancy of toxicities. Whether the cause was inherent to the specific NTCP models used in this study needs to be verified by future investigations. Because IMRT is increasingly used

Salvage conformal radiotherapy for biochemical recurrent prostate cancer after radical prostatectomy

Directory of Open Access Journals (Sweden)

Carlos R. Monti

2006-08-01

Full Text Available OBJECTIVE: Assess the results of salvage conformal radiotherapy in patients with biochemical failure after radical prostatectomy and identify prognostic factors for biochemical recurrence and toxicity of the treatment. MATERIALS AND METHODS: From June 1998 to November 2001, 35 patients were submitted to conformal radiotherapy for PSA > 0.2 ng/mL in progression after radical prostatectomy and were retrospectively analyzed. The mean dose of radiation in prostatic bed was of 77.4 Gy (68-81. Variables related to the treatment and to tumor were assessed to identify prognostic factors for biochemical recurrence after salvage radiotherapy. RESULTS: The median follow-up was of 55 months (17-83. The actuarial survival rates free of biochemical recurrence and free of metastasis at a distance of 5 years were 79.7% e 84.7%, respectively. The actuarial global survival rate in 5 years was 96.1%.The actuarial survival rate free of biochemical recurrence in 5 years was 83.3% with PSA pre-radiotherapy 1 and 2 (p = 0.023. Dose > 70 Gy in 30% of the bladder volume implied in more acute urinary toxicity (p = 0.035. The mean time for the development of late urinary toxicity was 21 months (12-51. Dose > 55 Gy in 50% bladder volume implied in more late urinary toxicity (p = 0.018. A patient presented late rectal toxicity of 2nd grade. CONCLUSIONS: Conformal radiotherapy showed to be effective for the control of biochemical recurrence after radical prostatectomy. Patients with pre-therapy PSA < 2 ng/mL have more biochemical control.

Choosing wisely after publication of level I evidence in breast cancer radiotherapy.

Science.gov (United States)

Niska, Joshua R; Keole, Sameer R; Pockaj, Barbara A; Halyard, Michele Y; Patel, Samir H; Northfelt, Donald W; Gray, Richard J; Wasif, Nabil; Vargas, Carlos E; Wong, William W

2018-01-01

Recent trials in early-stage breast cancer support hypofractionated whole-breast radiotherapy (WBRT) as part of breast-conserving therapy (BCT). Evidence also suggests that radiotherapy (RT) omission may be reasonable for some patients over 70 years. Among radiation-delivery techniques, intensity-modulated RT (IMRT) is more expensive than 3-dimensional conformal RT (3DCRT). Based on this evidence, in 2013, the American Society for Radiation Oncology (ASTRO) recommended hypofractionated schedules for women aged ≥50 years with early-stage breast cancer and avoiding routine use of IMRT for WBRT. To assess response to level I evidence and adherence to ASTRO recommendations, we evaluated the pattern of RT use for early-stage breast cancer at our National Comprehensive Cancer Network institution from 2006 to 2008 and 2011 to 2013 and compared the results with national trends. Data from a prospective database were extracted to include patients treated with BCT, aged ≥50 years, with histologic findings of invasive ductal carcinoma, stage T1-T2N0M0, estrogen receptor-positive, and HER2 normal. We retrospectively reviewed the medical records and estimated costs based on 2016 Hospital Outpatient Prospective Payment System (technical fees) and Medicare Physician Fee Schedule (professional fees). Among 55 cases from 2006 to 2008, treatment regimens were 11% hypofractionated, 69% traditional schedule, and 20% RT omission (29% of patients were aged >70 years). Among 83 cases from 2011 to 2013, treatment regimens were 54% hypofractionated, 19% traditional schedule, and 27% RT omission (48% of patients were aged >70 years). 3DCRT was used for all WBRT treatments. Direct medical cost estimates were as follows: 15 fractions 3DCRT, $7,197.87; 15 fractions IMRT, $11,232.33; 25 fractions 3DCRT, $9,731.39; and 25 fractions IMRT, $16,877.45. Despite apparent resistance to shorter radiation schedules in the United States, we demonstrate that rapid practice change in response to level I

A planning comparison of 7 irradiation options allowed in RTOG 1005 for early-stage breast cancer

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Chen, Guang-Pei, E-mail: gpchen@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Liu, Feng [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); White, Julia [Department of Radiation Oncology, The Ohio State University, Columbus, OH (United States); Vicini, Frank A. [Michigan Healthcare Professionals/21st Century Oncology, Farmington Hills, MI (United States); Freedman, Gary M. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Arthur, Douglas W. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

2015-04-01

This study compared the 7 treatment plan options in achieving the dose-volume criteria required by the Radiation Therapy Oncology Group (RTOG) 1005 protocol. Dosimetry plans were generated for 15 representative patients with early-stage breast cancer (ESBC) based on the protocol-required dose-volume criteria for each of the following 7 treatment options: 3D conformal radiotherapy (3DCRT), whole-breast irradiation (WBI) plus 3DCRT lumpectomy boost, 3DCRT WBI plus electron boost, 3DCRT WBI plus intensity-modulated radiation therapy (IMRT) boost, IMRT WBI plus 3DCRT boost, IMRT WBI plus electron boost, IMRT WBI plus IMRT boost, and simultaneous integrated boost (SIB) with IMRT. A variety of dose-volume parameters, including target dose conformity and uniformity and normal tissue sparing, were compared for these plans. For the patients studied, all plans met the required acceptable dose-volume criteria, with most of them meeting the ideal criteria. When averaged over patients, most dose-volume goals for all plan options can be achieved with a positive gap of at least a few tenths of standard deviations. The plans for all 7 options are generally comparable. The dose-volume goals required by the protocol can in general be easily achieved. IMRT WBI provides better whole-breast dose uniformity than 3DCRT WBI does, but it causes no significant difference for the dose conformity. All plan options are comparable for lumpectomy dose uniformity and conformity. Patient anatomy is always an important factor when whole-breast dose uniformity and conformity and lumpectomy dose conformity are considered.

Volumetric modulated arc radiotherapy for esophageal cancer

International Nuclear Information System (INIS)

Vivekanandan, Nagarajan; Sriram, Padmanaban; Syam Kumar, S.A.; Bhuvaneswari, Narayanan; Saranya, Kamalakannan

2012-01-01

A treatment planning study was performed to evaluate the performance of volumetric arc modulation with RapidArc (RA) against 3D conformal radiation therapy (3D-CRT) and conventional intensity-modulated radiation therapy (IMRT) techniques for esophageal cancer. Computed tomgraphy scans of 10 patients were included in the study. 3D-CRT, 4-field IMRT, and single-arc and double-arc RA plans were generated with the aim to spare organs at risk (OAR) and healthy tissue while enforcing highly conformal target coverage. The planning objective was to deliver 54 Gy to the planning target volume (PTV) in 30 fractions. Plans were evaluated based on target conformity and dose-volume histograms of organs at risk (lung, spinal cord, and heart). The monitor unit (MU) and treatment delivery time were also evaluated to measure the treatment efficiency. The IMRT plan improves target conformity and spares OAR when compared with 3D-CRT. Target conformity improved with RA plans compared with IMRT. The mean lung dose was similar in all techniques. However, RA plans showed a reduction in the volume of the lung irradiated at V 20Gy and V 30Gy dose levels (range, 4.62–17.98%) compared with IMRT plans. The mean dose and D 35% of heart for the RA plans were better than the IMRT by 0.5–5.8%. Mean V 10Gy and integral dose to healthy tissue were almost similar in all techniques. But RA plans resulted in a reduced low-level dose bath (15–20 Gy) in the range of 14–16% compared with IMRT plans. The average MU needed to deliver the prescribed dose by RA technique was reduced by 20–25% compared with IMRT technique. The preliminary study on RA for esophageal cancers showed improvements in sparing OAR and healthy tissue with reduced beam-on time, whereas only double-arc RA offered improved target coverage compared with IMRT and 3D-CRT plans.

Intensity-modulated radiotherapy prolongs the survival of patients with nasopharyngeal carcinoma compared with conventional two-dimensional radiotherapy: A 10-year experience with a large cohort and long follow-up.

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Zhang, Meng-Xia; Li, Jing; Shen, Guo-Ping; Zou, Xiong; Xu, Jun-Jie; Jiang, Rou; You, Rui; Hua, Yi-Jun; Sun, Ying; Ma, Jun; Hong, Ming-Huang; Chen, Ming-Yuan

2015-11-01

To evaluate the survival benefit of intensity-modulated radiotherapy (IMRT) compared with conventional two-dimensional radiotherapy (2D-CRT) in nasopharyngeal carcinoma (NPC) using a large cohort with long follow-up. We retrospectively analysed 7081 non-metastatic NPC patients who received curative IMRT or 2D-CRT from February 2002 to December 2011. Of the 7081 patients, 2245 (31.7%) were administered IMRT, while 4836 (68.3%) were administered 2D-CRT. At 5 years, the patients administered IMRT had significantly higher local relapse-free survival (LRFS), loco-regional relapse-free survival (LRRFS), progression-free survival (PFS) and overall survival (OS) (95.6%, 92.5%, 82.1% and 87.4%, respectively) than those administered 2D-CRT (90.8%, 88.5%, 76.7% and 84.5%, respectively; p<0.001). The distant metastasis-free survival (DMFS) was higher for IMRT than 2D-CRT, with borderline significance (87.6% and 85.7%, respectively; p=0.056). However, no difference was observed between IMRT and 2D-CRT in nodal relapse-free survival (NRFS; 96.3% and 97.4%, respectively; p=0.217). Multivariate analyses showed that IMRT was an independent protective prognostic factor for LRFS, LRRFS and PFS, but not NRFS, DMFS or OS. IMRT provided an improved LRFS, LRRFS and PFS in both the early and advanced T classifications and overall stage for non-disseminated NPC compared with 2D-CRT. However, no significant advantage was observed in NRFS, DMFS or OS when IMRT was used. Copyright © 2015 Elsevier Ltd. All rights reserved.

Left-sided breast cancer and risks of secondary lung cancer and ischemic heart disease. Effects of modern radiotherapy techniques

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Corradini, Stefanie; Ballhausen, Hendrik; Weingandt, Helmut; Freislederer, Philipp; Schoenecker, Stephan; Niyazi, Maximilian; Belka, Claus [University Hospital, LMU Munich, Department of Radiation Oncology, Munich (Germany); Simonetto, Cristoforo; Eidemueller, Markus [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, Neuherberg (Germany); Ganswindt, Ute [University Hospital, LMU Munich, Department of Radiation Oncology, Munich (Germany); Medical University, Department of Radiation Oncology, Innsbruck (Austria)

2018-03-15

Modern breast cancer radiotherapy techniques, such as respiratory-gated radiotherapy in deep-inspiration breath-hold (DIBH) or volumetric-modulated arc radiotherapy (VMAT) have been shown to reduce the high dose exposure of the heart in left-sided breast cancer. The aim of the present study was to comparatively estimate the excess relative and absolute risks of radiation-induced secondary lung cancer and ischemic heart disease for different modern radiotherapy techniques. Four different treatment plans were generated for ten computed tomography data sets of patients with left-sided breast cancer, using either three-dimensional conformal radiotherapy (3D-CRT) or VMAT, in free-breathing (FB) or DIBH. Dose-volume histograms were used for organ equivalent dose (OED) calculations using linear, linear-exponential, and plateau models for the lung. A linear model was applied to estimate the long-term risk of ischemic heart disease as motivated by epidemiologic data. Excess relative risk (ERR) and 10-year excess absolute risk (EAR) for radiation-induced secondary lung cancer and ischemic heart disease were estimated for different representative baseline risks. The DIBH maneuver resulted in a significant reduction of the ERR and estimated 10-year excess absolute risk for major coronary events compared to FB in 3D-CRT plans (p = 0.04). In VMAT plans, the mean predicted risk reduction through DIBH was less pronounced and not statistically significant (p = 0.44). The risk of radiation-induced secondary lung cancer was mainly influenced by the radiotherapy technique, with no beneficial effect through DIBH. VMAT plans correlated with an increase in 10-year EAR for radiation-induced lung cancer as compared to 3D-CRT plans (DIBH p = 0.007; FB p = 0.005, respectively). However, the EARs were affected more strongly by nonradiation-associated risk factors, such as smoking, as compared to the choice of treatment technique. The results indicate that 3D-CRT plans in DIBH pose the lowest

Does hormonal therapy influence sexual function in men receiving 3D conformal radiation therapy for prostate cancer?

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Chen, Christopher T.; Valicenti, Richard K.; Lu Jiandong; Derose, Troy; Dicker, Adam P.; Strup, Stephen E.; Mulholland, S. Grant; Hirsch, Irvin H.; McGinnis, David E.; Gomella, Leonard G.

2001-01-01

Purpose: We evaluated the effect of three-dimensional conformal radiation therapy (3D-CRT) with or without hormonal therapy (HT) on sexual function (SF) in prostate cancer patients whose SF was known before all treatment. Methods and Materials: Between March 1996 and March 1999, 144 patients received 3D-CRT (median dose = 70.2 Gy, range 66.6-79.2 Gy) for prostate cancer and had pre- and post-therapy SF data. All SF data were obtained with the O'Leary Brief SF Inventory, a self-administered, multidimensional, validated instrument. We defined total sexual potency as erections firm enough for penetration during intercourse. Mean follow-up time was 21 months (SD ± 11 months). The Wilcoxon signed-rank test was used to test for significance of the change from baseline. Results: Before 3D-CRT, 87 (60%) of 144 men were totally potent as compared to only 47 (47%) of 101 at 1-year follow-up. Of the 60 men totally potent at baseline and followed for at least 1 year, 35 (58%) remained totally potent. These changes corresponded to a significant reduction in SF (p<0.05). Patients who had 3D-CRT alone were more likely to be totally potent at 1 year than those receiving 3D-CRT with HT (56% vs. 31%, p=0.012); however, they were also more likely to be potent at baseline (71% vs. 44%, p=0.001). Although these two groups had a significant reduction in SF from baseline, their change was not significantly different from each other. Conclusion: These data indicate that 3D-CRT causes a significant reduction in total sexual potency as compared to pretreatment baseline. The addition of HT does not appear to increase the risk of sexual dysfunction

Prone Whole-Breast Irradiation Using Three-Dimensional Conformal Radiotherapy in Women Undergoing Breast Conservation for Early Disease Yields High Rates of Excellent to Good Cosmetic Outcomes in Patients With Large and/or Pendulous Breasts

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Bergom, Carmen; Kelly, Tracy; Morrow, Natalya; Wilson, J. Frank [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Walker, Alonzo [Department of Surgery, Medical College of Wisconsin, Milwaukee, WI (United States); Xiang Qun; Ahn, Kwang Woo [Division of Biostatistics, Medical College of Wisconsin, Milwaukee, WI (United States); White, Julia, E-mail: jwhite@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

2012-07-01

Purpose: To report our institution's experience using prone positioning for three-dimensional conformal radiotherapy (3D-CRT) to deliver post-lumpectomy whole breast irradiation (WBI) in a cohort of women with large and/or pendulous breasts, to determine the rate of acute and late toxicities and, more specifically, cosmetic outcomes. We hypothesized that using 3D-CRT for WBI in the prone position would reduce or eliminate patient and breast size as negative prognostic indicators for toxicities associated with WBI. Methods and Materials: From 1998 to 2006, 110 cases were treated with prone WBI using 3D-CRT. The lumpectomy, breast target volumes, heart, and lung were contoured on all computed tomography scans. A dose of 45-50 Gy was prescribed to the breast volume using standard fractionation schemes. The planning goals were {>=}95% of prescription to 95% of the breast volume, and 100% of boost dose to 95% of lumpectomy planning target volume. Toxicities and cosmesis were prospectively scored using the Common Terminology Criteria for Adverse Effects Version 3.0 and the Harvard Scale. The median follow-up was 40 months. Results: The median body mass index (BMI) was 33.6 kg/m{sup 2}, and median breast volume was 1396 cm{sup 3}. The worst toxicity encountered during radiation was Grade 3 dermatitis in 5% of our patient population. Moist desquamation occurred in 16% of patients, with only 2% of patients with moist desquamation outside the inframammary/axillary folds. Eleven percent of patients had Grade {>=}2 late toxicities, including Grade 3 induration/fibrosis in 2%. Excellent to good cosmesis was achieved in 89%. Higher BMI was associated with moist desquamation and breast pain, but BMI and breast volume did not impact fibrosis or excellent to good cosmesis. Conclusion: In patients with higher BMI and/or large-pendulous breasts, delivering prone WBI using 3D-CRT results in favorable toxicity profiles and high excellent to good cosmesis rates. Higher BMI was

Dosimetric impact of inter-observer variability for 3D conformal radiotherapy and volumetric modulated arc therapy: the rectal tumor target definition case

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Lobefalo, Francesca; Cozzi, Luca; Scorsetti, Marta; Mancosu, Pietro; Bignardi, Mario; Reggiori, Giacomo; Tozzi, Angelo; Tomatis, Stefano; Alongi, Filippo; Fogliata, Antonella; Gaudino, Anna; Navarria, Piera

2013-01-01

To assess the dosimetric effect induced by inter-observer variability in target definition for 3D-conformal RT (3DCRT) and volumetric modulated arc therapy by RapidArc (RA) techniques for rectal cancer treatment. Ten patients with rectal cancer subjected to neo-adjuvant RT were randomly selected from the internal database. Four radiation oncologists independently contoured the clinical target volume (CTV) in blind mode. Planning target volume (PTV) was defined as CTV + 7 mm in the three directions. Afterwards, shared guidelines between radiation oncologists were introduced to give general criteria for the contouring of rectal target and the four radiation oncologists defined new CTV following the guidelines. For each patient, six intersections (I) and unions (U) volumes were calculated coupling the contours of the various oncologists. This was repeated for the contours drawn after the guidelines. Agreement Index (AI = I/U) was calculated pre and post guidelines. Two RT plans (one with 3DCRT technique using 3–4 fields and one with RA using a single modulated arc) were optimized on each radiation oncologist’s PTV. For each plan the PTV volume receiving at least 95% of the prescribed dose (PTV V95%) was calculated for both target and non-target PTVs. The inter-operator AI pre-guidelines was 0.57 and was increased up to 0.69 post-guidelines. The maximum volume difference between the various CTV couples, drawn for each patient, passed from 380 ± 147 cm 3 to 137 ± 83 cm 3 after the introduction of guidelines. The mean percentage for the non-target PTV V95% was 93.7 ± 9.2% before and 96.6 ± 4.9%after the introduction of guidelines for the 3DCRT, for RA the increase was more relevant, passing from 86.5 ± 13.8% (pre) to 94.5 ± 7.5% (post). The OARs were maximally spared with VMAT technique while the variability between pre and post guidelines was not relevant in both techniques. The contouring inter-observer variability has dosimetric effects in the PTV coverage

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.

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

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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.

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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.

SU-F-T-646: SBRT Lung: Moving Beyond the 3D Conformal Paradigm with An Elekta VersaHD Accelerator

International Nuclear Information System (INIS)

Dalhart, A; Hyer, D; Allen, B; Flynn, R; Johnston, H

2016-01-01

Purpose: To develop a volumetric modulated arc therapy (VMAT) planning and delivery methodology for lung stereotactic body radiation therapy (SBRT) that addresses the unique geometric challenges presented when using an Elekta VersaHD linear accelerator. Methods: The Elekta VersaHD imaging panels are fixed at 160cm SID when deployed, limiting the ability to perform non-coplanar treatments due to collisions with the treatment table. The panels can be folded in a stored position for non-coplanar treatments, but in this configuration, longitudinal table travel is restricted by the space required for the folded panels. To overcome these design features, a non-coplanar VMAT technique was designed and evaluated for 6 patients that uses a superiorly placed isocenter near the apex of the lung. A coplanar VMAT technique with isocenter placement within the target was also assessed for each patient. Non-coplanar plans included three arcs, totalling 340° of arc angle, while coplanar plans included two arcs, totalling 280° of arc angle. Each technique avoided the contralateral lung and major overlap on patient skin. Corresponding 3DCRT plans were used as a baseline for each patient in evaluating VMAT plans. Results: Coplanar and noncoplanar VMAT plans yielded a high dose conformity index (CI) improvement of 6% and low dose CI improvements of 9% and 11%, respectively, over corresponding 3DCRT plans. While both VMAT techniques provided greater skin sparing compared to 3DCRT, the non-coplanar technique offered an improvement of 20% over the coplanar approach. Treatment time with for VMAT was ∼2.5 minutes compared to ∼10 minutes for 3DCRT. Conclusion: Two VMAT techniques were developed for lung SBRT that account for machine design limitations and provide greater dose conformity and normal tissue sparing than 3DCRT plans. The non-coplanar VMAT plans showed a marginal improvement over coplanar VMAT plans and may not warrant the additional complexity.

Salvage conformal radiotherapy for biochemical recurrent prostate cancer after radical prostatectomy

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Monti, Carlos R.; Nakamura, Ricardo A.; Ferrigno, Robson; Rossi Junior, Aristides; Kawakami, Neusa S.; Trevisan, Felipe A.

2006-01-01

Objective: Assess the results of salvage conformal radiotherapy in patients with biochemical failure after radical prostatectomy and identify prognostic factors for biochemical recurrence and toxicity of the treatment. Materials and methods: From June 1998 to November 2001, 35 patients were submitted to conformal radiotherapy for PSA ≥ 0.2 ng/mL in progression after radical prostatectomy and were retrospectively analyzed. The mean dose of radiation in prostatic bed was of 77.4 Gy (68-81). Variables related to the treatment and to tumor were assessed to identify prognostic factors for biochemical recurrence after salvage radiotherapy. Results: The median follow-up was of 55 months (17-83). The actuarial survival rates free of biochemical recurrence and free of metastasis at a distance of 5 years were 79.7% e 84.7%, respectively. The actuarial global survival rate in 5 years was 96.1%.The actuarial survival rate free of biochemical recurrence in 5 years was 83.3% with PSA pre-radiotherapy ≤ 1, 100% when > 1 and ≤ 2, and 57.1% when > 2 (p = 0.023). Dose > 70 Gy in 30% of the bladder volume implied in more acute urinary toxicity (p = 0.035). The mean time for the development of late urinary toxicity was 21 months (12-51). Dose > 55 Gy in 50% bladder volume implied in more late urinary toxicity (p = 0.018). A patient presented late rectal toxicity of second grade. Conclusions: Conformal radiotherapy showed to be effective for the control of biochemical recurrence after radical prostatectomy. Patients with pre-therapy PSA < 2 ng/mL have more biochemical control. (author)

The place of conformal radiotherapy in the routine work: national investigation of SFRO members'opinion

International Nuclear Information System (INIS)

Lagrange, J.L.; Lipinski, F.

2001-01-01

National French investigation of the using of conformal radiotherapy in routine work, has been made in 2001, in 180 radiotherapeutic centers. Eighty responses have been obtained and analyzed. Conformal radiotherapy is used in 88% and virtual simulation in 60% of these centers. There is a heterogeneity in the equipment of these institutions, most of them have one or two machines. The accelerator equipment differs, and the availability of multi-leaf collimators and electronic portal imaging is limited. Actually only eleven centers have IMRT, eight have projects to install. Only six centers have CT-scans, used mainly for simulation. In 75% of centers conformal radiotherapy have been used in the treatment of CNS-tumors, head and neck cancers, prostate, and non-small cell lung carcinoma. If there are more equipment and human facilities to use conformal radiotherapy, this treatment can be proposed to patients with breast cancer, rectal and gynecological tumors. According 90% of responses, all prostatic cancers need conformal radiotherapy. The analysis of routine use of conformal radiotherapy in France shows an important heterogeneity but it seems that there is an agreement with objectives of this treatment. (authors)

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.

Bladder filling variation during conformal radiotherapy for rectal cancer

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Sithamparam, S.; Ahmad, R.; Sabarudin, A.; Othman, Z.; Ismail, M.

2017-05-01

Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients.

Bladder filling variation during conformal radiotherapy for rectal cancer

International Nuclear Information System (INIS)

Sithamparam, S; Ahmad, R; Sabarudin, A; Othman, Z; Ismail, M

2017-01-01

Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients. (paper)

Constituent Components of Out-of-Field Scatter Dose for 18-MV Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy: A Comparison With 6-MV and Implications for Carcinogenesis

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Ruben, Jeremy D.; Smith, Ryan; Lancaster, Craig M.; Haynes, Matthew; Jones, Phillip; Panettieri, Vanessa

2014-01-01

Purpose: To characterize and compare the components of out-of-field dose for 18-MV intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) and their 6-MV counterparts and consider implications for second cancer induction. Methods and Materials: Comparable plans for each technique/energy were delivered to a water phantom with a sloping wall; under full scatter conditions; with field edge abutting but outside the bath to prevent internal/phantom scatter; and with shielding below the linear accelerator head to attenuate head leakage. Neutron measurements were obtained from published studies. Results: Eighteen-megavolt IMRT produces 1.7 times more out-of-field scatter than 18-MV 3D-CRT. In absolute terms, however, differences are just approximately 0.1% of central axis dose. Eighteen-megavolt IMRT reduces internal/patient scatter by 13%, but collimator scatter (C) is 2.6 times greater than 18-MV 3D-CRT. Head leakage (L) is minimal. Increased out-of-field photon scatter from 18-MV IMRT carries out-of-field second cancer risks of approximately 0.2% over and above the 0.4% from 18-MV 3D-CRT. Greater photoneutron dose from 18-MV IMRT may result in further maximal, absolute increased risk to peripheral tissue of approximately 1.2% over 18-MV 3D-CRT. Out-of-field photon scatter remains comparable for the same modality irrespective of beam energy. Machine scatter (C+L) from 18 versus 6 MV is 1.2 times higher for IMRT and 1.8 times for 3D-CRT. It is 4 times higher for 6-MV IMRT versus 3D-CRT. Reduction in internal scatter with 18 MV versus 6 MV is 27% for 3D-CRT and 29% for IMRT. Compared with 6-MV 3D-CRT, 18-MV IMRT increases out-of-field second cancer risk by 0.2% from photons and adds 0.28-2.2% from neutrons. Conclusions: Out-of-field photon dose seems to be independent of beam energy for both techniques. Eighteen-megavolt IMRT increases out-of-field scatter 1.7-fold over 3D-CRT because of greater collimator scatter despite

Gastro-intestinal and genito-urinary morbidity after 3D conformal radiotherapy of prostate cancer: observations of a randomized trial

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Koper, Peter C.; Jansen, Peter; Putten, Wim van; Os, Marjolein van; Wijnmaalen, Arend J.; Lebesque, Joos V.; Levendag, Peter C.

2004-01-01

Background and purpose: The late morbidity of a randomized study was analyzed after a follow up of 2 years. The difference in intestinal morbidity was analyzed as a function of the treatment arm and dose volume parameters. The correlation with acute toxicity and (pre-existing) bowel complaints was investigated. Patients and methods: 266 T1-4N0M0 prostate cancer patients were randomized for conventional (open fields) and 3D conformal radiotherapy using beams eye view blocked fields with the same dose (66 Gy) and gross target volume-planning target volume margin (15 mm). Apart from the RTOG toxicity scoring system a patient self-assessment questionnaire was used to obtain detailed information on morbidity. Results: At 2 years there is only a trend for less rectal toxicity (grade≥1) in favor of the conformal radiotherapy (grade 1, 47 versus 40% and grade 2, 10 versus 7% for conventional and conformal radiotherapy, respectively (P=0.1). A significant relation was found between late rectal toxicity (grade≥1) and the volume of the anus and rectum exposed to≥90% tumor dose (TD). A highly significant relationship is observed between acute rectum and anal toxicity and late rectal toxicity. The patient self-assessment questionnaire analysis revealed that patients are most bothered by compliance related symptoms like urgency, soiling and fecal loss. In a multivariate analysis, all other variables loose significance, when anal volume exposed to≥90% TD and pre-treatment defaecation frequency are accounted for. Late anal toxicity is low and related only to acute anal toxicity. Late bladder toxicity is related solely to pre-treatment frequency and overall urological symptoms. The incidence of grade 2 toxicity increases with a factor 2.5-4 when (stool or urine) frequency is unfavorable at the start of treatment. Conclusions: Conformal radiotherapy at the dose level of 66 Gy does not significantly decrease the incidence of rectal, anal and bladder toxicity compared to

Analysis of second malignancies after modern radiotherapy versus prostatectomy for localized prostate cancer

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Huang Jiayi; Kestin, Larry L.; Ye, Hong; Wallace, Michelle; Martinez, Alvaro A.; Vicini, Frank A.

2011-01-01

Purpose: To clarify the risk of developing second primary cancers (SPCs) after radiotherapy (RT) versus prostatectomy for localized prostate cancer (PCa) in the modern era. Methods: The RT cohort consisted of 2120 patients matched on a 1:1 basis with surgical patients according to age and follow-up time. RT techniques consisted of conventional or two-dimensional RT (2DRT, 36%), three-dimensional conformal RT and/or intensity modulated RT (3DCRT/IMRT, 29%), brachytherapy (BT, 16%), and a combination of 2DRT and BT (BT boost, 19%). Results: The overall SPC risk was not significantly different between the matched-pair (HR 1.14, 95% CI 0.94-1.39), but the risk became significant >5 years or >10 years after RT (HR 1.86, 95% CI 1.36-2.55; HR 4.94, 95% CI 2.18-11.2, respectively). The most significant sites of increased risk were bladder, lymphoproliferative, and sarcoma. Of the different RT techniques, only 2DRT was associated with a significantly higher risk (HR 1.76, 95% CI 1.32-2.35), but not BT boost (HR 0.83, 95% CI 0.50-1.38), 3DCRT/IMRT (HR 0.81, 95% CI 0.55-1.21), or BT (HR 0.53, 95% CI 0.28-1.01). Conclusions: Radiation-related SPC risk varies depending on the RT technique and may be reduced by using BT, BT boost, or 3DCRT/IMRT.

Beam angle selection for intensity-modulated radiotherapy (IMRT) treatment of unresectable pancreatic cancer: are noncoplanar beam angles necessary?

Science.gov (United States)

Chang, D S; Bartlett, G K; Das, I J; Cardenes, H R

2013-09-01

External beam radiation therapy with concurrent chemotherapy (CRT) is widely used for the treatment of unresectable pancreatic cancer. Noncoplanar (NCP) 3D conformal radiotherapy (3DCRT) and coplanar (CP) IMRT have been reported to lower the radiation dose to organs at risk (OARs). The purpose of this article is to examine the utility of noncoplanar beam angles in IMRT for the management of pancreatic cancer. Sixteen patients who were treated with CRT for unresectable adenocarcinoma of the pancreatic head or neck were re-planned using CP and NCP beams in 3DCRT and IMRT with the Varian Eclipse treatment planning system. Compared to CP IMRT, NCP IMRT had similar target coverage with slightly increased maximum point dose, 5,799 versus 5,775 cGy (p = 0.008). NCP IMRT resulted in lower mean kidney dose, 787 versus 1,210 cGy (p kidney dose, but did not improve other dose-volume criteria. The use of NCP beam angles is preferred only in patients with risk factors for treatment-related kidney dysfunction.

Australian and New Zealand three-dimensional conformal radiation therapy consensus guidelines for prostate cancer

International Nuclear Information System (INIS)

Skala, M.; Berry, M.; Kneebone, A.; Gogna, K.; Turner, S.; Rolfo, A.; Haworth, A.

2004-01-01

Three-dimensional conformal radiation therapy (3DCRT) has been shown to reduce normal tissue toxicity and allow dose escalation in the curative treatment of prostate cancer. The Faculty of Radiation Oncology Genito-Urinary Group initiated a consensus process to generate evidence-based guidelines for the safe and effective implementation of 3DCRT. All radiation oncology departments in Australia and New Zealand were invited to complete a survey of their prostate practice and to send representatives to a consensus workshop. After a review of the evidence, key issues were identified and debated. If agreement was not reached, working parties were formed to make recommendations. Draft guidelines were circulated to workshop participants for approval prior to publication. Where possible, evidence-based recommendations have been made with regard to patient selection, risk stratification, simulation, planning, treatment delivery and toxicity reporting. This is the first time a group of radiation therapists, physicists and oncologists representing professional radiotherapy practice across Australia and New Zealand have worked together to develop best-practice guidelines. These guidelines should serve as a baseline for prospective clinical trials, outcome research and quality assurance. Copyright (2004) Blackwell Science Pty Ltd

Comparative analysis of dosimetric parameters of three different radiation techniques for patients with Graves’ ophthalmopathy treated with retro-orbital irradiation

International Nuclear Information System (INIS)

Lee, Victor HF; Ng, Sherry CY; Choi, Cheuk Wai; Luk, Mai Yee; Leung, To Wai; Au, Gordon KH; Kwong, Dora LW

2012-01-01

We would like to investigate the if IMRT produced better target coverage and dose sparing to adjacent normal structures as compared with 3-dimensional conformal radiotherapy (3DCRT) and lateral opposing fields (LOF) for patients with Graves’ ophthalmopathy treated with retro-orbital irradiation. Ten consecutive patients diagnosed with Graves’ ophthalmopathy were prospectively recruited into this study. An individual IMRT, 3DCRT and LOF plan was created for each patient. Conformity index (CI), homogeneity index (HI) and other dosimetric parameters of the targets and organs-at-risk (OAR) generated by IMRT were compared with the other two techniques. Mann–Whitney U test demonstrated that CI generated by IMRT was superior to that produced by 3DCRT and LOF (p=0.005 for both respectively). Similarly HI with IMRT was proven better than 3DCRT (p=0.007) and LOF (p=0.005). IMRT gave rise to better dose sparing to some OARs including globes, lenses and optic nerves as compared with 3DCRT but not with LOF. IMRT, as compared with 3DCRT and LOF, was found to have a better target coverage, conformity and homogeneity and dose sparing to some surrounding structures, despite a slight increase but clinically negligible dose to other structures. Dosimetrically it might be a preferred treatment technique and a longer follow up is warranted to establish its role in routine clinical use

Intensity-modulated three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Mohan, Radhe

1996-01-01

Optimized intensity-modulated treatments one of the important advances in photon radiotherapy. Intensity modulation provides a greatly increased control over dose distributions. Such control can be maximally exploited to achieve significantly higher levels of conformation to the desired clinical objectives using sophisticated optimization techniques. Safe, rapid and efficient delivery of intensity-modulated treatments has become feasible using a dynamic multi-leaf collimator under computer control. The need for all other field shaping devices such as blocks, wedges and compensators is eliminated. Planning and delivery of intensity-modulated treatments is amenable to automation and development of class solutions for each treatment site and stage which can be implemented not only at major academic centers but on a wide scale. A typical treatment involving as many as 10 fields can be delivered in times shorter than much simpler conventional treatments. The main objective of the course is to give an overview of the current state of the art of planning and delivery methods of intensity-modulated treatments. Specifically, the following topics will be covered using representative optimized plans and treatments: 1. A typical procedure for planning and delivering an intensity-modulated treatment. 2. Quantitative definition of criteria (i.e., the objective function) of optimization of intensity-modulated treatments. Clinical relevance of objectives and the dependence of the quality of optimized intensity-modulated plans upon whether the objectives are stated purely in terms of simple dose or dose-volume criteria or whether they incorporate biological indices. 3. Importance of the lateral transport of radiation in the design of intensity-modulated treatments. Impact on dose homogeneity and the optimum choice of margins. 4. Use of intensity-modulated treatments in escalation of tumor dose for the same or lower normal tissue dose. Fractionation of intensity-modulated treatments

Intensity-modulated three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Mohan, Radhe

1997-01-01

Optimized intensity-modulated treatments one of the important advances in photon radiotherapy. Intensity modulation provides a greatly increased control over dose distributions. Such control can be maximally exploited to achieve significantly higher levels of conformation to the desired clinical objectives using sophisticated optimization techniques. Safe, rapid and efficient delivery of intensity-modulated treatments has become feasible using a dynamic multi-leaf collimator under computer control. The need for all other field shaping devices such as blocks, wedges and compensators is eliminated. Planning and delivery of intensity-modulated treatments is amenable to automation and development of class solutions for each treatment site and stage which can be implemented not only at major academic centers but on a wide scale. A typical treatment involving as many as 10 fields can be delivered in times shorter than much simpler conventional treatments. The main objective of the course is to give an overview of the current state of the art of planning and delivery methods of intensity-modulated treatments. Specifically, the following topics will be covered using representative optimized plans and treatments: 1. A typical procedure for planning and delivering an intensity-modulated treatment. 2. Quantitative definition of criteria (i.e., the objective function) of optimization of intensity-modulated treatments. Clinical relevance of objectives and the dependence of the quality of optimized intensity-modulated plans upon whether the objectives are stated purely in terms of simple dose or dose-volume criteria or whether they incorporate biological indices. 3. Importance of the lateral transport of radiation in the design of intensity-modulated treatments. Impact on dose homogeneity and the optimum choice of margins. 4. Use of intensity-modulated treatments in escalation of tumor dose for the same or lower normal tissue dose. Fractionation of intensity-modulated treatments

Sildenafil citrate (Viagra) and erectile dysfunction following external beam radiotherapy for prostate cancer: a randomized, double-blind, placebo-controlled, cross-over study

International Nuclear Information System (INIS)

Incrocci, Luca; Koper, Peter C.M.; Hop, Wim C.J.; Slob, A. Koos

2001-01-01

Purpose: To determine the efficacy of sildenafil citrate (Viagra) in patients with erectile dysfunction after three-dimensional conformal external beam radiotherapy (3D-CRT) for prostate cancer. Methods and Materials: 406 patients with complaints of erectile dysfunction and who completed radiation at least 6 months before the study were approached by mail. 3D-CRT had been delivered (mean dose 68 Gy). Sixty patients were included and entered a double-blind, placebo-controlled, cross-over study lasting 12 weeks. They received during 2 weeks 50 mg of sildenafil or placebo; at Week 2 the dose was increased to 100 mg in case of unsatisfactory erectile response. At Week 6, patients crossed over to the alternative treatment. Data were collected using the International Index of Erectile Function (IIEF) questionnaire, and side effects were recorded. Results: Mean age was 68 years. All patients completed the study. For most questions of the IIEF questionnaire there was a significant increase in mean scores from baseline with sildenafil, but not with placebo. Ninety percent of the patients needed a dose adjustment to 100 mg sildenafil. Side effects were mild or moderate. Conclusion: Sildenafil is well tolerated and effective in improving erectile function of patients with ED after 3D-CRT for prostate cancer

Radiological response and dosimetry in physical phantom of head and neck for 3D conformational radiotherapy

International Nuclear Information System (INIS)

Thompson, Larissa

2013-01-01

Phantoms are tools for simulation of organs and tissues of the human body in radiology and radiotherapy. This thesis describes the development, validation and, most importantly, the use of a physical head and neck phantom in radiology and radiotherapy, with the purpose of evaluating dose distribution using Gafchromic EBT2 film in 15 MV 3D conformal radiotherapy. The work was divided in two stages, (1) development of new equivalent tissues and improvement of the physical phantom, and (2) use of the physical phantom in experimental dosimetry studies. In phase (1) parameters such as mass density, chemical composition of tissues, anatomical and biometric measurements were considered, as well as aspects of imaging by computed tomography (CT) and radiological response representation in Hounsfield Units (HU), which were compared with human data. Radiological experiments of in-phantom simulated brain pathologies were also conducted. All those results matched human-sourced data, therefore the physical phantom is a suitable simulator that may be used to enhance radiological protocols and education in medical imaging. The main objective in phase (2) was to evaluate the spatial dose distribution in a brain tumor simulator inserted inside the head and neck phantom developed by the Ionizing Radiation Research Group (NRI), exposed to 15 MV 3D conformal radiotherapy, for internal dose assessment. Radiation planning was based on CT images of the physical phantom with a brain tumor simulator made with equivalent material. The treatment planning system (TPS), CAT3D software, used CT images and prescribed a dose of 200 cGy, distributed in three fields of radiation, in a T-shaped pattern. The TPS covered the planning treatment volume (PTV) with 97% of the prescribed dose. A solid water phantom and radiochromic Gafchromic EBT2 film were used for calibration procedures, generating a dose response curve as a function of optical density (OD). After calibration and irradiation, the film

A case study of radiotherapy planning for a bilateral metal hip prosthesis prostate cancer patient

International Nuclear Information System (INIS)

Su, Andy; Reft, Chester; Rash, Carla; Price, Jennifer; Jani, Ashesh B.

2005-01-01

The purpose of this report is to communicate the observed advantage of intensity-modulated radiotherapy (IMRT) in a patient with bilateral metallic hip prostheses. In this patient with early-stage low-risk disease, a dose of 74 Gy was planned in two phases-an initial 50 Gy to the prostate and seminal vesicles and an additional 24 Gy to the prostate alone. Each coplanar beam avoided the prosthesis in the beam's eye view. Using the same target expansions for each phase, IMRT and 3D-conformal radiotherapy (CRT) plans were compared for target coverage and inhomogeneity as well as dose to the bladder and rectum. The results of the analysis demonstrated that IMRT provided superior target coverage with reduced dose to normal tissues for both individual phases of the treatment plan as well as for the composite treatment plan. The dose to the rectum was significantly reduced with the IMRT technique, with a composite V80 of 35% for the IMRT plan versus 70% for 3D-CRT plan. Similarly, the dose to the bladder was significantly reduced with a V80 of 9% versus 20%. Overall, various dosimetric parameters revealed the corresponding 3D-CRT plan would not have been acceptable. The results indicate significant success with IMRT in a clinical scenario where there were no curative alternatives for local treatment other than external beam radiotherapy. Therefore, definitive external beam radiation of prostate cancer patients with bilateral prosthesis is made feasible with IMRT. The work described herein may also have applicability to other groups of patients, such as those with gynecological or other pelvic malignancies

Optimized volumetric modulated arc therapy versus 3D-CRT for early stage mediastinal Hodgkin lymphoma without axillary involvement: a comparison of second cancers and heart disease risk.

Science.gov (United States)

Filippi, Andrea Riccardo; Ragona, Riccardo; Piva, Cristina; Scafa, Davide; Fiandra, Christian; Fusella, Marco; Giglioli, Francesca Romana; Lohr, Frank; Ricardi, Umberto

2015-05-01

The purpose of this study was to evaluate the risks of second cancers and cardiovascular diseases associated with an optimized volumetric modulated arc therapy (VMAT) planning solution in a selected cohort of stage I/II Hodgkin lymphoma (HL) patients treated with either involved-node or involved-site radiation therapy in comparison with 3-dimensional conformal radiation therapy (3D-CRT). Thirty-eight patients (13 males and 25 females) were included. Disease extent was mediastinum alone (n=8, 21.1%); mediastinum plus unilateral neck (n=19, 50%); mediastinum plus bilateral neck (n=11, 29.9%). Prescription dose was 30 Gy in 2-Gy fractions. Only 5 patients had mediastinal bulky disease at diagnosis (13.1%). Anteroposterior 3D-CRT was compared with a multiarc optimized VMAT solution. Lung, breast, and thyroid cancer risks were estimated by calculating a lifetime attributable risk (LAR), with a LAR ratio (LAR(VMAT)-to-LAR(3D-CRT)) as a comparative measure. Cardiac toxicity risks were estimated by calculating absolute excess risk (AER). The LAR ratio favored 3D-CRT for lung cancer induction risk in mediastinal alone (P=.004) and mediastinal plus unilateral neck (P=.02) presentations. LAR ratio for breast cancer was lower for VMAT in mediastinal plus bilateral neck presentations (P=.02), without differences for other sites. For thyroid cancer, no significant differences were observed, regardless of anatomical presentation. A significantly lower AER of cardiac (P=.038) and valvular diseases (Pdisease extent. In a cohort of patients with favorable characteristics in terms of disease extent at diagnosis (large prevalence of nonbulky presentations without axillary involvement), optimized VMAT reduced heart disease risk with comparable risks of thyroid and breast cancer, with an increase in lung cancer induction probability. The results are however strongly influenced by the different anatomical presentations, supporting an individualized approach. Copyright © 2015 Elsevier

Dosimetric comparison of axilla and groin radiotherapy techniques for high-risk and locally advanced skin cancer

International Nuclear Information System (INIS)

Mattes, Malcolm D.; Zhou, Ying; Berry, Sean L.; Barker, Christopher A.

2016-01-01

Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung V 20 (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum D max (13.6 vs. 38.9 Gy), bowel D 200cc (7.3 vs. 23.1 Gy), femur D 50 (34.6 vs. 57.2 Gy), and genitalia D max (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus D mean (16.9 vs. 22.4 Gy), brachial plexus D 5 (57.4 vs. 61.3 Gy), bladder D 5 (26.8 vs. 36.5 Gy), and femur D 50 (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients

Dosimetric comparison of axilla and groin radiotherapy techniques for high-risk and locally advanced skin cancer

Energy Technology Data Exchange (ETDEWEB)

Mattes, Malcolm D.; Zhou, Ying; Berry, Sean L.; Barker, Christopher A. [Memorial Sloan Kettering Cancer Center, New York (United States)

2016-06-15

Radiation therapy targeting axilla and groin lymph nodes improves regional disease control in locally advanced and high-risk skin cancers. However, trials generally used conventional two-dimensional radiotherapy (2D-RT), contributing towards relatively high rates of side effects from treatment. The goal of this study is to determine if three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), or volumetric-modulated arc therapy (VMAT) may improve radiation delivery to the target while avoiding organs at risk in the clinical context of skin cancer regional nodal irradiation. Twenty patients with locally advanced/high-risk skin cancers underwent computed tomography simulation. The relevant axilla or groin planning target volumes and organs at risk were delineated using standard definitions. Paired t-tests were used to compare the mean values of several dose-volumetric parameters for each of the 4 techniques. In the axilla, the largest improvement for 3D-CRT compared to 2D-RT was for homogeneity index (13.9 vs. 54.3), at the expense of higher lung V{sub 20} (28.0% vs. 12.6%). In the groin, the largest improvements for 3D-CRT compared to 2D-RT were for anorectum D{sub max} (13.6 vs. 38.9 Gy), bowel D{sub 200cc} (7.3 vs. 23.1 Gy), femur D{sub 50} (34.6 vs. 57.2 Gy), and genitalia D{sub max} (37.6 vs. 51.1 Gy). IMRT had further improvements compared to 3D-CRT for humerus D{sub mean} (16.9 vs. 22.4 Gy), brachial plexus D{sub 5} (57.4 vs. 61.3 Gy), bladder D{sub 5} (26.8 vs. 36.5 Gy), and femur D{sub 50} (18.7 vs. 34.6 Gy). Fewer differences were observed between IMRT and VMAT. Compared to 2D-RT and 3D-CRT, IMRT and VMAT had dosimetric advantages in the treatment of nodal regions of skin cancer patients.

Probability of mediastinal involvement in non-small-cell lung cancer: a statistical definition of the clinical target volume for 3-dimensional conformal radiotherapy?

International Nuclear Information System (INIS)

Giraud, Philippe; De Rycke, Yann; Lavole, Armelle; Milleron, Bernard; Cosset, Jean-Marc; Rosenzweig, Kenneth E.

2006-01-01

Purpose: Conformal irradiation (3D-CRT) of non-small-cell lung carcinoma (NSCLC) is largely based on precise definition of the nodal clinical target volume (CTVn). A reduction of the number of nodal stations to be irradiated would facilitate tumor dose escalation. The aim of this study was to design a mathematical tool based on documented data to predict the risk of metastatic involvement for each nodal station. Methods and Materials: We reviewed the large surgical series published in the literature to identify the main pretreatment parameters that modify the risk of nodal invasion. The probability of involvement for the 17 nodal stations described by the American Thoracic Society (ATS) was computed from all these publications. Starting with the primary site of the tumor as the main characteristic, we built a probabilistic tree for each nodal station representing the risk distribution as a function of each tumor feature. Statistical analysis used the inversion of probability trees method described by Weinstein and Feinberg. Validation of the software based on 134 patients from two different populations was performed by receiver operator characteristic (ROC) curves and multivariate logistic regression. Results: Analysis of all of the various parameters of pretreatment staging relative to each level of the ATS map results in 20,000 different combinations. The first parameters included in the tree, depending on tumor site, were histologic classification, metastatic stage, nodal stage weighted as a function of the sensitivity and specificity of the diagnostic examination used (positron emission tomography scan, computed tomography scan), and tumor stage. Software is proposed to compute a predicted probability of involvement of each nodal station for any given clinical presentation. Double cross validation confirmed the methodology. A 10% cutoff point was calculated from ROC and logistic model giving the best prediction of mediastinal lymph node involvement. Conclusion

Brainstem tolerance to conformal radiotherapy of skull base tumors

International Nuclear Information System (INIS)

Debus, J.; Hug, E.B.; Munzenrider, J.E.; Liebsch, N.J.; O'Farrell, D.; Efird, J.; Daly, W.; Suit, H.D.

1996-01-01

Purpose/Objective: Brainstem tolerance to inhomogenous radiation doses applied by modern conformal radiotherapy has not yet been examined. The aim of this study was to analyse the incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Materials and Methods: Between 1974 and 1995, 367 patients with chordomas (n=195) and chondrosarcomas (n=172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. All patients had previously undergone biopsy, subtotal or total tumor removal. 104 patients had two or more surgical procedures before radiotherapy. Following 3D treatment planning with delineation of target volumes and critical non-target structures, dose distributions and dose volume histograms were calculated [at the time of treatment delivery]. Radiotherapy was given once a day, 1.8 Gy or CGE (Cobalt Gy Equivalent: Proton Gy X 1.1) per fraction, 5 fractions per week, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Dose distributions were developed to limit dose to brainstem surface and center; current plans limit dose to surface and center to ≤64 CGE and ≤53 CGE, respectively. Brainstem toxicity was scored according to the RTOG grading system. Results: Follow-up ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem symptoms, attributable to the treatment, developed in 17 of 282 patients with local tumor control (6.0%), resulting in death of three patients. The mean time to onset of symptoms was 17 months (range: 4.5 to 177 months). These symptoms appeared in 89.5% within 3 years. Grading of the brainstem toxicity is listed in table 1. Actuarial rates of 5 and 10 year toxicity free survival were 87% and 82% respectively. Increased risk of brainstem toxicity was significantly associated with maximum brainstem dose

Conformal three dimensional radiotherapy treatment planning in Lund

International Nuclear Information System (INIS)

Knoos, T.; Nilsson, P.; Anders, A.

1995-01-01

The use of conformal therapy is based on 3-dimensional treatment planning as well as on methods and routines for 3-dimensional patient mapping, 3-dimensional virtual simulation and others. The management of patients at the Radiotherapy Department at the University Hospital in Lund (Sweden) is discussed. About 2100 new patients are annually treated with external radiotherapy using seven linear accelerators. Three of the accelerators have dual photon energies and electron treatment facilities. A multi-leaf collimator as well as an electronic portal imaging device are available on one machine. Two simulators and an in-house CT-scanner are used for treatment planning. From 1988 to 1992 Scandiplan (Umplan) was used. Since 1992, the treatment planning system is TMS (HELAX AB, Sweden), which is based on the pencil beam algorithm of Ahnesjo. The calculations use patient modulated accelerator specific energy fluence spectra which are compiled with pencil beams from Monte Carlo generated energy absorption kernels. Heterogeneity corrections are performed with results close to conventional algorithms. Irregular fields, either from standard or individual blocks and from multi-leaf collimators are handled by the treatment planning system. The field shape is determined conveniently using the beam's eye view. The final field shape is exported electronically to either the block cutting machine or the multileaf collimator control computer. All patient fields are checked against the beam's eye view during simulation using manual methods. Treatment verification is performed by portal films and in vivo dosimetry with silicon diodes or TL-dosimetry. Up to now, approximately 4400 patients have received a highly individualized 3-dimensional conformal treatment

Comparisons of dose-volume histograms for proton-beam versus 3-D conformal X-ray therapy in patients with stage I non-small cell lung cancer

International Nuclear Information System (INIS)

Wang, Changlu; Nakayama, Hidetsugu; Sugahara, Shinji; Sakae, Takeji; Tokuuye, Koichi

2009-01-01