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Sample records for accelerated radiotherapy carbogen

  1. ACUTE TOXICITY PROFILE AND COMPLIANCE TO ACCELERATED RADIOTHERAPY PLUS CARBOGEN AND NICOTINAMIDE FOR CLINICAL STAGE T2-4 LARYNGEAL CANCER : RESULTS OF A PHASE III RANDOMIZED TRIAL

    Janssens, Geert O.; Terhaard, Chris H.; Doornaert, Patricia A.; Bijl, Hendrik P.; van den Ende, Piet; Chin, Alim; Pop, Lucas A.; Kaanders, Johannes H.

    2012-01-01

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with

  2. Acute toxicity profile and compliance to accelerated radiotherapy plus carbogen and nicotinamide for clinical stage T2-4 laryngeal cancer: results of a phase III randomized trial.

    Janssens, G.O.R.J.; Terhaard, C.H.J.; Doornaert, P.A.; Bijl, H.P.; Ende, P. van den; Chin, A.; Pop, L.A.M.; Kaanders, J.H.A.M.

    2012-01-01

    PURPOSE: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. METHODS AND MATERIALS: From April 2001 to February 2008, 345 patients with

  3. Acute Toxicity Profile and Compliance to Accelerated Radiotherapy Plus Carbogen and Nicotinamide for Clinical Stage T2–4 Laryngeal Cancer: Results of a Phase III Randomized Trial

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with cT2–4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2–4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Results: Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moist desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. Conclusion: With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2–4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit.

  4. Acute Toxicity Profile and Compliance to Accelerated Radiotherapy Plus Carbogen and Nicotinamide for Clinical Stage T2-4 Laryngeal Cancer: Results of a Phase III Randomized Trial

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Terhaard, Chris H. [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands); Doornaert, Patricia A. [Department of Radiation Oncology, VU University Medical Center, Amsterdam (Netherlands); Bijl, Hendrik P. [Department of Radiation Oncology, University Medical Center Groningen, Groningen (Netherlands); Ende, Piet van den [Department of Radiation Oncology, Maastricht University Medical Centre, Maastricht (Netherlands); Chin, Alim [Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands); Pop, Lucas A.; Kaanders, Johannes H. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2012-02-01

    Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with cT2-4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2-4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Results: Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moist desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. Conclusion: With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2-4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit.

  5. Radiotherapy with carbogen breathing and nicotinamide in head and neck cancer: feasibility and toxicity

    The feasibility and early toxicity of radiotherapy with carbogen breathing and nicotinamide was tested in 74 head and neck cancer patients. Forty patients with laryngeal and hypopharyngeal tumors were treated with an accelerated schedule combined with carbogen alone (16) or with carbogen and nicotinamide (24). Thirty-four patients with far advanced unresectable tumors of the oral cavity and oropharynx received conventional radiotherapy with carbogen [16] or with carbogen and nicotinamide (18). Some enhancement of skin reaction was observed with nicotinamide but this remained well within limits of tolerance. With the accelerated regimen there was increased severity of mucosal damage expressed as confluent mucositis in 95% of patients which required healing times of 3-4 months in four patients. Eventually restoration of the mucosal lining was complete in all cases. Nausea and vomiting are the most frequent side effects of nicotinamide and were reported by 60% and 36% of the subjects, respectively. In 26% this was reason to discontinue drug intake. Severe renal dysfunction was associated with nicotinamide intake in two patients of this study and in one other patient who presented later. It is our conclusion that radiotherapy combined with carbogen and nicotinamide is a safe treatment with manageable side effects. We recommend not to give nicotinamide concomitantly with nephrotoxic medication or to patients who have impaired renal function. Preliminary tumor control rates are encouraging and clinical testing will be continued

  6. Radiosensitisation in normal tissues with oxygen, carbogen or nicotinamide: therapeutic gain comparisons for fractionated x-ray schedules

    Methods: Radiosensitisation with oxygen, carbogen or nicotinamide alone and oxygen or carbogen combined with nicotinamide was compared in early and late responding normal tissues in rodents. X-ray treatments were delivered as single doses or fractionated schedules of 2 fractions in 1 day, 2, 12 and 36 fractions in an overall time of 12 days and 10 fractions in 5 or 12 days. Acute skin reactions, survival of intestinal crypts, breathing rate, reduction in the packed red-cell volume and clearance of 51Cr-EDTA were used as assays of epidermal, gut, lung and renal damage. Results: Relative to air-breathing mice, carbogen or oxygen produced a small, and not always significant, increase in sensitivity (enhancement ratios ≤ 1.15) in gut, lung and kidneys; however, in skin a dose enhancement of 1.2-1.3 was observed. The effect of nicotinamide in air, carbogen or oxygen was studied only in lung and gut. The drug produced variable but generally significant increases in radiosensitisation (≤ 1.26) in all three gases. Relative to treatments in air, enhancement ratios for nicotinamide alone were usually slightly higher than those observed when either carbogen or oxygen were administered without the drug. With all three modifiers (i.e. oxygen, carbogen, nicotinamide alone or for the drug-gas combinations) there was no significant change in the enhancement ratios observed as the number of radiation dose fractions was varied. Conclusions: Comparisons with fractionated X-ray studies done previously in rodent tumours indicate that a therapeutic benefit, relative to lung, gut and renal damage, would be observed with oxygen or carbogen alone but not with nicotinamide alone. The greatest gain would be achieved with the combination of carbogen and nicotinamide, with which a benefit was observed even relative to epidermal damage. These results indicate that some decrease in normal tissue tolerance could be observed when using these modifiers in clinical radiotherapy and, although

  7. ARCON in experimental and clinical radiotherapy

    Rojas Callejas, Ana Maria

    2004-01-01

    xHypoxia and repopulation of tumour clonogens are two important determinants of treatment outcome in radiotherapy. In general clinical evidence indicates that loco-regional control may be reduced with long overall treatment times and for tumours with low pre-treatment levels of oxygen. Experimental studies with normobaric carbogen and oxygen showed a two-fold enhancement of the efficacy of radiation in a mouse tumour model when combining oxygen with treatment acceleration. It was then demonst...

  8. Accelerated radiotherapy for advanced laryngeal cancer

    The purpose of this study was to evaluate a single institution's outcome for patients with advanced laryngeal cancer treated with accelerated radiotherapy (RT). Fifty-eight patients with advanced laryngeal cancer were treated with curative intent with accelerated RT during the period 1990-1998. Patients received radiotherapy alone or with induction chemotherapy. The 5-year local control (LC) and loco-regional control (LRC) probabilities were both 49% for T3 and 75% for T4 tumors. The 5-year disease-free survival probability was 46% and 68% and overall survival probability was 30% and 39% for T3 and T4 tumors respectively. No significant statistical difference in outcome was found, either between T3 and T4 tumors, or between patients who received induction chemotherapy and those who did not. The treatment results for advanced laryngeal cancer at this institution were comparable to those reported in the literature. The results for T3 and T4 were similar. T4 classification alone should not be an exclusion criterion for larynx preservation. Overall survival was poor, partly because of a high incidence of deaths from intercurrent diseases

  9. Accelerated radiotherapy for advanced laryngeal cancer

    Haugen, Hedda; Mercke, Claes [Sahlgrenska Univ. Hospital, Goeteborg (Sweden). Dept. of Oncology; Johansson, Karl-Axel [Sahlgrenska Univ. Hospital, Goeteborg (Sweden). Dept. of Radiophysics; Ejnell, Hasse; Edstroem, Staffan [Sahlgrenska Univ. Hospital, Goeteborg (Sweden). Dept. of Oto-Rhino-Laryngology

    2005-07-01

    The purpose of this study was to evaluate a single institution's outcome for patients with advanced laryngeal cancer treated with accelerated radiotherapy (RT). Fifty-eight patients with advanced laryngeal cancer were treated with curative intent with accelerated RT during the period 1990-1998. Patients received radiotherapy alone or with induction chemotherapy. The 5-year local control (LC) and loco-regional control (LRC) probabilities were both 49% for T3 and 75% for T4 tumors. The 5-year disease-free survival probability was 46% and 68% and overall survival probability was 30% and 39% for T3 and T4 tumors respectively. No significant statistical difference in outcome was found, either between T3 and T4 tumors, or between patients who received induction chemotherapy and those who did not. The treatment results for advanced laryngeal cancer at this institution were comparable to those reported in the literature. The results for T3 and T4 were similar. T4 classification alone should not be an exclusion criterion for larynx preservation. Overall survival was poor, partly because of a high incidence of deaths from intercurrent diseases.

  10. Improvement of Brain Tissue Oxygenation by Inhalation of Carbogen

    Ashkanian, M.; Borghammer, P.; Gjedde, A.; Ostergaard, L.; Vafaee, M.

    2008-01-01

    confirmed by statistical cluster analysis. Oxygen and carbogen were equally potent in increasing oxygen saturation of arterial blood (Sa(O2)). The present data demonstrate that inhalation of carbogen increases both CBF and Sa(O2) in healthy adults. In conclusion we speculate that carbogen inhalation is...... sufficient for optimal oxygenation of healthy brain tissue, whereas carbogen induces concomitant increases of CBF and Sa(O2).......Hyperoxic therapy for cerebral ischemia is suspected to reduce cerebral blood flow (CBF), due to the vasoconstrictive effect of oxygen on cerebral arterioles. We hypothesized that vasodilation predominates when 5% CO(2) is added to the inhaled oxygen (carbogen). Therefore, we used positron emission...

  11. A therapeutic benefit from combining normobaric carbogen or oxygen with nicotinamide in fractionated X-ray treatments

    The ability of normobaric oxygen and carbogen (95 percent O2 + 5 percent CO2) combined with nicotinamide to enhance the radiosensitivity of two rodent adenocarcinomas and of mouse skin and kidneys was compared with the effects of radiation in air and without the drug. A comparison of the results in tumors and normal tissues showed that significant therapeutic benefit was obtained with normobaric oxygen and carbogen combined with nicotinamide. Toxic side effects of the treatment are unlikely, as prolonged administration of nicotinamide is well tolerated in man. The combination of normobaric carbogen with nicotinamide could be an effective method of enhancing tumor radiosensitivity in clinical radiotherapy where hypoxia limits the outcome of treatment. (author). 45 refs.; 4 fig.; 4 tabs

  12. Potential role of hypoxia imaging using 18F-FAZA PET to guide hypoxia-driven interventions (carbogen breathing or dose escalation) in radiation therapy

    Background and purpose: Hypoxia-driven intervention (oxygen manipulation or dose escalation) could overcome radiation resistance linked to tumor hypoxia. Here, we evaluated the value of hypoxia imaging using 18F-FAZA PET to predict the outcome and guide hypoxia-driven interventions. Material and methods: Two hypoxic rat tumor models were used: rhabdomyosarcoma and 9L-glioma. For the irradiated groups, the animals were divided into two subgroups: breathing either room air or carbogen. 18F-FAZA PET images were obtained just before the irradiation to monitor the hypoxic level of each tumor. Absolute pO2 were also measured using EPR oximetry. Dose escalation was used in Rhabdomyosarcomas. Results: For 9L-gliomas, a significant correlation between 18F-FAZA T/B ratio and tumor growth delay was found; additionally, carbogen breathing dramatically improved the tumor response to irradiation. On the contrary, Rhabdomyosarcomas were less responsive to hyperoxic challenge. For that model, an increase in growth delay was observed using dose escalation, but not when combining irradiation with carbogen. Conclusions: 18F-FAZA uptake may be prognostic of outcome following radiotherapy and could assess the response of tumor to carbogen breathing. 18F-FAZA PET may help to guide the hypoxia-driven intervention with irradiation: carbogen breathing in responsive tumors or dose escalation in tumors non-responsive to carbogen

  13. Quality assurance protocol for linear accelerators used in radiotherapy

    Radiotherapy is a modality of choice for treatment of malignant diseases. Linear accelerators are the most common devices for implementing external radiation therapy. Taking into account the fact during the treatment, healthy tissue will inevitably be exposed to ionizing radiation, predicted dose in each radiotherapy case should be delivered with the greatest possible accuracy. Medical requirement for quality treatment achieving means as mach as possible dose into volume of interest and the greatest possible healthy tissue protection. From radiation protection point of view, occupational exposure of the staff involved in radiotherapy process should be minimized. To be able to reach it, consistent adherence to the Quality Assurance Programme is necessary. It should be in accordance with higher national and international protocols, because they give guidelines on the necessary standards, procedures, processes, resources and responsibilities that should be defined in structuring the overall radiotherapy quality management. As a part of this Master thesis, quality management as well as Quality Assurance Programme that is necessary to be applied in each radiotherapy center have been prepared. Mandatory dosimetry measurements included in the internal recommendations are also emphasized. Measurement results and external audit by IAEA indicated high accuracy and quality radiotherapy dose delivering in Macedonia. Based on the measurements and analysis, the aim of this Master thesis is offering a Quality Assurance Protocol for external beam radiotherapy that can be used on the national level in Republic of Macedonia. (Author)

  14. Radiotherapy using a laser proton accelerator

    Murakami, Masao; Miyajima, Satoshi; Okazaki, Yoshiko; Sutherland, Kenneth L; Abe, Mitsuyuki; Bulanov, Sergei V; Daido, Hiroyuki; Esirkepov, Timur Zh; Koga, James; Yamagiwa, Mitsuru; Tajima, Toshiki

    2008-01-01

    Laser acceleration promises innovation in particle beam therapy of cancer where an ultra-compact accelerator system for cancer beam therapy can become affordable to a broad range of patients. This is not feasible without the introduction of a technology that is radically different from the conventional accelerator-based approach. The laser acceleration method provides many enhanced capabilities for the radiation oncologist. It reduces the overall system size and weight by more than one order of magnitude. The characteristics of the particle beams (protons) make them suitable for a class of therapy that might not be possible with the conventional accelerator, such as the ease for changing pulse intensity, the focus spread, the pinpointedness, and the dose delivery in general. A compact, uncluttered system allows a PET device to be located in the vicinity of the patient in concert with the compact gantry. The radiation oncologist may be able to irradiate a localized tumor by scanning with a pencil-like particle...

  15. Neutronic fields produced by a lineal accelerator for radiotherapy

    Measurements and Monte Carlo calculations has been utilized to determine the dosimetric features as well as the neutron spectra of photoneutrons produced around an 18 MV linear accelerator for radiotherapy. Measurements were carried out with bare and Cd covered thermoluminescent dosimeters, TLD600 and TLD700, as well as inside a paraffine moderator. TLD pairs were also utilized as thermal neutrons inside a Bonner sphere spectrometer (au)

  16. Formation Mechanism of Carbogenic Nanoparticles with Dual Photoluminescence Emission

    Krysmann, Marta J.

    2012-01-18

    We present a systematic investigation of the formation mechanism of carbogenic nanoparticles (CNPs), otherwise referred to as C-dots, by following the pyrolysis of citric acid (CA)-ethanolamine (EA) precursor at different temperatures. Pyrolysis at 180 °C leads to a CNP molecular precursor with a strongly intense photoluminescence (PL) spectrum and high quantum yield formed by dehydration of CA-EA. At higher temperatures (230 °C) a carbogenic core starts forming and the PL is due to the presence of both molecular fluorophores and the carbogenic core. CNPs that exhibit mostly or exclusively PL arising from carbogenic cores are obtained at even higher temperatures (300 and 400 °C, respectively). Since the molecular fluorophores predominate at low pyrolysis temperatures while the carbogenic core starts forming at higher temperatures, the PL behavior of CNPs strongly depends on the conditions used for their synthesis. © 2011 American Chemical Society.

  17. Accelerated radiotherapy in advanced head and neck cancer

    The purpose of the study is to present the reasons for introducing concomitant boost accelerated radiotherapy (CBAR) and its practical aspects at advanced head and neck carcinomas (HNC). Accelerated clonogenic repopulation of the tumor during radiotherapy necessitates its termination within the shortest possible term. The differentiated effect of the fractionated dose on both early and late response of tissues requires the use of several smaller daily fractions with an interval between exceeding six hours during all the time of radiotherapy or a part of it. If there is no data about earlier kinetics of the tumor cells, schemes with total dose 69-72 Gy are given preference. The practical aspects of CBAR also are presented: 1. specificity of the clinical target volume (ICRU 50) considering the requirements for beam and fields; 2. irradiation techniques most frequently used and 3. the method of patient immobilization. The characteristic features of CBAR are also discussed: 1. The primary tumor and its subclinical diffusion are irradiated in standard fields or in such with exclusion of the spinal cord at dose up to 54 in 30 fractions for 5.5 weeks. During the first two days, two daily fractions at six-hours interval are delivered with partial exclusion of the spinal cord. The primary tumor is given during the last 2.5 weeks up to total dose 69-72 Gy with a second daily fraction of 1.5 Gy six hours after the first one; 2. The current concepts for spinal cord radiation tolerance and very high risk of transverse myelitis in some accelerated radiotherapeutical schemes are also discussed. The therapeutic approach described is based on the experience got from the conventional fractionation; 3. Without neglecting enhanced acute toxicity CBAR is recommended as a well tolerated radiotherapeutical method

  18. Photoluminescent carbogenic nanoparticles directly derived from crude biomass

    Krysmann, Marta J.

    2012-01-01

    We present an environmentally benign, energy efficient and readily scalable approach to synthesize photoluminescent carbogenic nanoparticles directly from soft tissue biomass. Our approach relies on the pyrolytic decomposition of grass that gives rise to the formation of well-defined nanoparticles. The carbogenic nanoparticles can be readily surface modified, generating a series of highly selective photoluminescent materials that exhibit remarkable stability upon prolonged exposure to aggressive, high-temperature, high-salinity environment. © 2012 The Royal Society of Chemistry.

  19. Effects of carbogen plus fractionated irradiation on KHT tumor oxygenation

    Background and purpose: Numerous studies have demonstrated improvements in the oxygenation of tumor cells following both irradiation and carbogen breathing. The current studies were initiated to measure the combined effects of carbogen inhalation plus single and multi-dose irradiation on tumor oxygen availability, to better define the underlying physiological relationships. Materials and methods: Using KHT murine sarcomas, radiation was delivered to the tumor-bearing legs of non-anesthetized mice. Tumors were quick-frozen prior to or following single or multifraction irradiation and carbogen breathing, and intravascular HbO2 saturation profiles were determined cryospectrophotometrically. Results: HbO2 levels for blood vessels located near the tumor surface initially decreased following 10 Gy irradiation, then increased and remained elevated. Interior HbO2 levels remained unchanged. Following 2.5 Gy, HbO2 changes were minimal. At 24 h following 10 Gy, HbO2 levels were significantly increased compared to non-irradiated controls, and carbogen breathing produced no additional benefit. At 24 h following five fractions of 2 Gy, HbO2 levels throughout the tumor volume were significantly higher in carbogen breathing animals than in air breathing controls. Conclusions: Although peripheral blood vessels demonstrated substantial improvements in oxygenation following irradiation, oxygen availability nearer the tumor center remained at very low levels. The utility of carbogen in enhancing tumor oxygen availability was maintained following five clinically relevant fractions. At higher doses, radiation-induced enhancements in HbO2 levels overshadowed the carbogen effect. For either air or carbogen breathing, a decrease in the percentage of vessels with very low oxygen content did not appear to be a major factor in the reoxygenation of the KHT tumor

  20. Accelerated Deformable Registration of Repetitive MRI during Radiotherapy in Cervical Cancer

    Noe, Karsten Østergaard; Tanderup, Kari; Kiritsis, Christian; Dimopoulos, Johannes; Sørensen, Thomas Sangild; Lindegaard, Jacob; Grau, Cai

    Tumour regression and organ deformations during radiotherapy (RT) of cervical cancer represent major challenges regarding accurate conformation and calculation of dose when using image-guided adaptive radiotherapy. Deformable registration algorithms are able to handle organ deformations, which can...... be useful with advanced tools such as auto segmentation of organs and dynamic adaptation of radiotherapy. The aim of this study was to accelerate and validate deformable registration in MRI-based image-guided radiotherapy of cervical cancer.    ...

  1. Biological dose volume histograms during conformal hypofractionated accelerated radiotherapy for prostate cancer

    Radiobiological data suggest that prostate cancer has a low α/β ratio. Large radiotherapy fractions may, therefore, prove more efficacious than standard radiotherapy, while radiotherapy acceleration should further improve control rates. This study describes the radiobiology of a conformal hypofractionated accelerated radiotherapy scheme for the treatment of high risk prostate cancer. Anteroposterior fields to the pelvis deliver a daily dose of 2.7 Gy, while lateral fields confined to the prostate and seminal vesicles deliver an additional daily dose of 0.7 Gy. Radiotherapy is accomplished within 19 days (15 fractions). Dose volume histograms, calculated for tissue specific α/β ratios and time factors, predict a high biological dose to the prostate and seminal vesicles (77-93 Gy). The biological dose to normal pelvic tissues is maintained at standard levels. Radiobiological dosimetry suggests that, using hypofractionated and accelerated radiotherapy, high biological radiation dose can be given to the prostate without overdosing normal tissues

  2. Mild hyperthermia alone or in combination with carbogen is effective in increasing tumor pO2

    Purpose/Objective: We have studied the effect of mild temperature hyperthermia (MTH) on pO2 with or without carbogen breathing and the radio response in three different rodent tumors. Materials and Methods: SCK mammary carcinoma of A/J mice, FSall fibrosarcoma of C3H mice, and R3230 AC mammary carcinoma of Fischer rats were used. The changes in pO2 in these tumors by MTH alone or in combination with carbogen (95% O2 + 5% CO2) breathing were studied. The MTH was done by immersing the legs bearing s.c. tumors into a water bath and the pO2 was measured using an Eppendorf pO2 Histograph machine. The influence of MTH on the effect of X-irradiation (250 kVp) on tumors was investigated with tumor growth delay and the in vivo-in vitro excision assay for hypoxic cell fraction. Results: The pO2 in all three tumor types was increased significantly by MTH. The most effective heating conditions were 60 min at 41.5 deg. C for SCK and FSall, and 30 min at 42.5 deg. C for R3230 AC. Carbogen breathing alone increased the pO2, but the effect of carbogen was dramatically enhanced when combined with heating. FSall tumors heated at 41.5 deg. C for 60 min before receiving a dose of 20 Gy took an average of 3 days longer than tumors receiving heat after irradiation to grow to four times their original volume. The identical conditions in SCK tumors heated before irradiation caused a 5 day growth delay. Effect of heating before or after irradiation on cell survival in tumor was determined using in vivo-in vitro excision assay method. Heating FSall tumors before irradiation for 30 min at 41.5 deg. C caused marked reduction in the hypoxic cell fraction. Cell survival studies in the SCK and R3230 AC tumors are currently being studied as well as the radiation response of all three tumors after heating combined with carbogen breathing. Conclusion: These results indicate that MTH is very effective in increasing the tumor oxygenation and the response of human tumors to radiotherapy. The

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

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

    2016-01-01

    Background 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 no...

  4. Prospective Trial of Accelerated Partial Breast Intensity-Modulated Radiotherapy

    Purpose: To examine the feasibility and acute toxicities of an accelerated, partial breast, intensity-modulated radiotherapy (IMRT) protocol. Methods and Materials: Between February 2004 and August 2005, 55 patients with Stage I breast cancer and initial follow-up were enrolled at four facilities on a HealthONE and Western institutional review board-approved accelerated partial breast IMRT protocol. All patients were treated in 10 equal fractions delivered twice daily within 5 consecutive days. The first 7 patients were treated to 34 Gy, and the remaining 48 patients were treated to 38.5 Gy. Results: The median follow-up after IMRT was 10 months (range, <1-19) and after diagnosis was 11.5 months (range, 2-21). No local or distant recurrences developed. The T stage distribution was as follows: T1a in 11 patients, T1b in 24, and T1c in 20. The median tumor size was 9 mm (range, 1-20 mm). Breast cosmesis was judged by the patient as poor by 2, good by 12, and excellent by 40 (1 patient was legally blind) and by the physician as poor for 1, good for 10, and excellent for 44 patients. Breast pain, as judged by patient, was none in 34, mild in 19, moderate in 2, and severe in 0 patients. There was a single report of telangiectasia but no incidents of significant edema. Compared with historic controls for whom three-dimensional treatment planning techniques were used, IMRT provided similar dose delivery to the target while reducing the volume of normal breast included in the 100%, 75%, and 50% isodose lines. Conclusion: This initial report prospectively explored the feasibility of accelerated partial breast IMRT. After short-term follow-up, the dose delivery and clinical outcomes were very acceptable. We believe this regimen deserves additional investigation under institutional review board guidance

  5. Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

    Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a “wait-and-scan” group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dose to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.

  6. Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

    Rasmussen, Rune, E-mail: rune333@gmail.com [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Claesson, Magnus [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Stangerup, Sven-Eric [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Roed, Henrik [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Christensen, Ib Jarle [Finsen Laboratory, Rigshospitalet, Copenhagen (Denmark); Caye-Thomasen, Per [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Juhler, Marianne [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark)

    2012-08-01

    Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a 'wait-and-scan' group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dose to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.

  7. Avoidance of treatment interruption: an unrecognized benefit of accelerated radiotherapy in oropharyngeal carcinomas?

    Allal, Abdelkarim Said; De Pree, Christian; Dulguerov, Pavel; Bieri, Sabine; Maire, Daphne Isabel; Kurtz, John

    1999-01-01

    To assess the impact of treatment interruption on the potential gain in locoregional control obtained with accelerated radiotherapy (RT) compared with conventionally fractionated RT in patients with oropharyngeal carcinomas.

  8. Salvage surgery after radical accelerated radiotherapy with concomitant boost technique for head and neck carcinomas

    Taussky, Daniel; Dulguerov, Pavel; Allal, Abdelkarim Said

    2005-01-01

    Definitive radiotherapy (RT) for head and neck cancer is increasingly used to preserve organ function, whereas surgery is reserved for treatment failure. However, data are sparse regarding the feasibility of salvage surgery, particularly for unselected patients after accelerated RT.

  9. Late course accelerated hyperfractionation radiotherapy for nasopharyngeal carcinoma

    Objective: To study the efficacy of late course accelerated fractionation (LCAF) radio- therapy in the treatment of nasopharyngeal carcinoma(NPC). The end-po s were local control, radiation-induced complications, factors influencing survival. Methods: From December 1995 to April 1998, 178 NPC patients were admitted for radiation treatment. The radiation beam used was 60Co γ or 6 MV X-ray. For the first two-thirds of the treatment, two daily fractions of 1.2 Gy were given to the primary lesion , with an interval of ≥6 hours, 5 days per week to a total dose of 48 Gy/40 fractions, over a period of 4 weeks. For the last one third of the treatment, i. e. beginning from the 5th week, an accelerated hyperfractionation schedule was carried out. The dose per fraction was increased to 1.5 Gy, 2 fractions per day with an interval of ≥6 hours, the total dose for this part of the protocol was 30 Gy/20 fractions over 2 weeks. Thus the total dose was 78 Gy in 60 fractions in 6 weeks. Results: All patients completed the treatment. Acute mucositis: none in 2 patients, Grade 1 in 43 , Grade 2 in 78, Grade 3 in 52, and Grade 4 in 3 patients. Local control rate: the 5 -year nasopharyngeal local control rate was 87.7%, and the cervical lymph node local control rate was 85.7%. The 5-year distant metastasis rate was 26.1%, and 5-year survivals was 67.9%. Sixteen patients had radiation-induced cranial nerve palsy. Conclusions: With this treatment schedule, patient's tolerance is good, local control and 5 year survivals are better than control groups of conventional fractionation and hyperfractionation radiotherapy. Radiation-related late complication does not increase. Randomized clinical trials are being carried out to further confirm the efficacy of LCAF for nasopharyngeal carcinoma. (authors)

  10. Hyperfractionated or accelerated radiotherapy in head and neck cancer: a meta-analysis

    Bourhis, J.; Overgaard, Jens; Audry, H.;

    2006-01-01

    BACKGROUND: Several trials have studied the role of unconventional fractionated radiotherapy in head and neck squamous cell carcinoma, but the effect of such treatment on survival is not clear. The aim of this meta-analysis was to assess whether this type of radiotherapy could improve survival......-specified categories: hyperfractionated, accelerated, and accelerated with total dose reduction. FINDINGS: 15 trials with 6515 patients were included. The median follow-up was 6 years. Tumours sites were mostly oropharynx and larynx; 5221 (74%) patients had stage III-IV disease (International Union Against Cancer...... radiotherapy (2% with accelerated fractionation without total dose reduction and 1.7% with total dose reduction at 5 years, p=0.02). There was a benefit on locoregional control in favour of altered fractionation versus conventional radiotherapy (6.4% at 5 years; p<0.0001), which was particularly efficient in...

  11. Accelerated hyperfractionated radiotherapy for locally advanced cervix cancer

    Purpose: A phase II trial was designed to evaluate the toxicity and outcome of patients with locally advanced cervix cancer treated with accelerated hyperfractionated radiotherapy (AHFX). Methods and Materials: In this prospective trial, AHFX doses of 1.25 Gy were administered twice daily at least 6 hours apart to a total pelvic dose of 57.5 Gy. A booster dose was then administered via either low-dose rate brachytherapy or external beam therapy to a smaller volume. All patients were accrued and treated at Peter MacCallum Cancer Institute (PMCI) between 1986 until April 1991. Results: Sixty-one eligible patients were enrolled in this protocol; 2 (3.2%) had Stage IIB; 42 (68.9%) had Stage III; 8 (13.1%) had Stage IV and 9 (14.8%) had recurrent cervical cancer. Fifty-two patients (85%) completed the planned external beam without a treatment break. Thirty patients had acute toxicity that required regular medication. One patient died of acute treatment related toxicity. Fifty-five patients received booster therapy: 45 with intrauterine brachytherapy, 6 with interstitial brachytherapy, and 4 with external beam. The median follow-up of surviving patients was 6 years. Overall 5-year survival is 27% and 5-year relapse free survival is 36%. Nineteen patients died with pelvic disease and the actuarial local control rate was 66%. There were 8 severe late complications observed in 7 patients. Seven required surgical intervention (an actuarial rate of 27%). Five patients also required total hip replacement. Conclusions: The local control rate was favorable compared with other series that have used standard fractionation, although overall survival remained similar. The severe late complication rate was high for this protocol and higher than similar protocols reported in the literature

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

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

  13. Feasibility and early results of accelerated radiotherapy for head and neck carcinoma in the elderly

    Allal, Abdelkarim Said; Maire, Daphne Isabel; Becker, Minerva; Dulguerov, Pavel

    2000-01-01

    Accelerated radiotherapy (RT) represents a promising method with which to improve the treatment outcome in patients with head and neck carcinoma. However, its applicability to elderly patients has not been well established. This study assessed treatment toxicities, patient compliance, and oncologic results in patients age >/= 70 years who were treated with an accelerated concomitant boost RT schedule.

  14. Fractionated stereotactic radiotherapy of vestibular schwannomas accelerates hearing loss

    Rasmussen, Rune; Claesson, Magnus; Stangerup, Sven-Eric;

    2012-01-01

    To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hear......To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea...

  15. Accelerated Partial Breast Irradiation with Intensity-Modulated Radiotherapy Is Feasible for Chinese Breast Cancer Patients

    He, Zhenyu; Wu, Sangang; Zhou, Juan; Li, Fengyan; Sun, Jiayan; Lin, Qin; Lin, Huanxin; Guan, Xunxing

    2014-01-01

    Purpose Several accelerated partial breast irradiation (APBI) techniques are being investigated in patients with early-stage breast cancer. The present study evaluated the feasibility, early toxicity, initial efficacy, and cosmetic outcomes of accelerated partial breast intensity-modulated radiotherapy (IMRT) for Chinese female patients with early-stage breast cancer after breast-conserving surgery. Methods A total of 38 patients met the inclusion criteria and an accelerated partial breast in...

  16. Fractionated irradiation combined with carbogen breathing and nicotinamide of two human glioblastomas grafted in nude mice

    SUN, Lin-Quan; Buchegger, Franz; COUCKE, Philippe; MIRIMANOFF

    2001-01-01

    This study addressed the potential radiosensitizing effect of nicotinamide and/or carbogen on human glioblastoma xenografts in nude mice. U-87MG and LN-Z308 tumors were irradiated with either 20 fractions over 12 days or 5 fractions over 5 days in air-breathing mice, mice injected with nicotinamide, mice breathing carbogen, or mice receiving nicotinamide plus carbogen. The responses to treatment were assessed using local control and moist desquamation. In U-87MG tumors, the enhancement ratios...

  17. Comparison of remote results of conventional fractionation radiotherapy and late course accelerated hyperfractionation radiotherapy for nasopharyngeal carcinoma

    Objective: To compare the long-term effects of conventional fractionation (CF) radio-therapy and late course accelerated hyperfractionation (LCAHF) radiotherapy of nasopharyngeal carcinoma (NPC), and to arrive at a appropriate NPC radiotherapy protocol. Methods: According to the criteria, 496 patients with NPC were allotted to our retrospective analysis, including 269 in the CF group and 227 in the LCAHF group. Two large lateral opposing fields were first used to treat the nasopharynx and the upper neck at a fraction of 2 Gy daily, 5 days per week. After 36-40 Gy, two small lateral opposing fields were used to boost the primary tumor while the spinal cord shielded. In the CF group, the accumulated total dose of naso-pharynx was 68-76 Gy at 2 Gy daily. In the LCAHF group, the radiation fraction of primary tumor was 1.5 Gy twice daily, with a minimum of six-hour interval in the late course. The accumulated total dose was 69-72 Gy. Survival was assessed by Kaplan-Meier method and Logrank analysis. Results: The 5-year primary site control, tumor-free survival and overall survival rates was 65.4% ,61.5% and 68.1% in the LCAHF group and 52.8%, 49.4% and 57.5% in the CF group. The difference between the two groups were significant (P=0.006, 0.006 and 0.031). Further analysis showed that LCAHF improved the primary site control, tumor-free survival and overall survival rates of T2-T3 NPC (P0.05). Conclusions: When compared with conventional fractionation radiotherapy, late course accelerated hyperfractionation radiotherapy, being tolerable, definitely can improve the local control, tumor-free survival and overall survival in patients with nasopharyngeal carcinoma. But the recurrence rates of cervical lymph nodes and distant metastasis were similar in between these two groups. (authors)

  18. Prolonged survival when temozolomide is added to accelerated radiotherapy for glioblastoma multiforme

    The goal of this study was to evaluate accelerated radiotherapy with and without temozolomide (TMZ) for glioblastoma multiforme (GBM). This retrospective analysis evaluated 86 patients with histologically proven GBM who were treated with accelerated radiotherapy of 1.8 Gy twice daily to a total dose of 54 Gy within 3 weeks. Median age was 62 years and median Karnofsky index was 90. A total of 41 patients received radiotherapy only from 2002-2005 and 45 patients were treated with TMZ concomitantly and after radiotherapy from 2005-2007. Median overall survival (OS) was 12.5 months and 2-year OS was 15.4%. Patient characteristics were well balanced between the two groups except for better performance status (p = 0.05) and higher frequency of retreatment for the first recurrence (p = 0.02) in the TMZ group. Age at diagnosis (HR 2.83) and treatment with TMZ (HR 0.60) were correlated with OS in the multivariate analysis: treatment with and without TMZ resulted in median OS of 16 months and 11.3 months, respectively. Hematological toxicity grade > II was observed in 2/45 patients and 5/37 patients during simultaneous radiochemotherapy and adjuvant TMZ. TMZ added to accelerated radiotherapy for GBM resulted in prolonged overall survival with low rates of severe hematological toxicity. (orig.)

  19. PhoNeS: A novel approach to BNCT with conventional radiotherapy accelerators

    PhoNeS (Photo Neutron Source) is an INFN project devoted to the optimization of the neutron production and moderation in radiotherapy linear accelerators. LinAcs producing high energy (15-25MeV) photon beams are becoming widespread. At this energy neutron photo-production is unavoidable and the neutron dose must be controlled and reduced during normal radiotherapy. A technique known as BNCT (Boron Neutron Capture Therapy) uses neutrons for radiotherapic treatments: the cells are given a drug containing B10 which undergoes fission after neutron capture, inducing heavy damages to the DNA of the cell itself. This paper will describe the moderator developed by PhoNeS and the results in terms of neutron flux and spectrum and photon contamination of the measurements performed on several radiotherapy accelerators

  20. Particle-beam accelerators for radiotherapy and radioisotopes

    The philosophy used in developing the new PIGMI technology was that the parameters chosen for physics research machines are not necessarily the right ones for a dedicated therapy or radioisotope machine. In particular, the beam current and energy can be optimized, and the design should emphasize minimum size, simplicity and reliability of operation, and economy in capital and operating costs. A major part of achieving these goals lay in raising the operating frequency and voltage gradient of the accelerator, which shrinks the diameter and length of the components. Several other technical innovations resulted in major system improvements. One of these is a radically new type of accelerator structure named the radio-frequency quadrupole (RFQ) accelerator. This allowed us to eliminate the large, complicated ion source used in previous ion accelerators, and to achieve a very high quality accelerated beam. Also, by using advanced permanent magnet materials to make the focusing elements, the system becomes much simpler. Other improvements have been made in all of the accelerator components and in the methods for operating them. These will be described, and design and costing information examples given for several possible therapy and radioisotope production machines

  1. Quality Assesment Of Photon And Electron Beams From Siemens PRIMUS Radiotherapy Accelerator

    There are two types of radiation from SIEMENS Primus Radiotherapy Accelerator at the National Cancer Hospital (K Hospital): electron and photon beams. Electron beams with four different energies of 6; 9; 12 and 15 MeV. Photon beams with two different energies: 6 MV and 15 MV. The symmetry as well as flatness of profiles created by all these beams are very important factors using in clinical practice. This report presents the method using water phantom to define absorbed dose distribution in medium of all beams. This is an effective and accurate method to define quality of radiation beams with different field sizes using in radiotherapy. (author)

  2. Comparison between continuous accelerated hyperfractionated and late-course accelerated hyperfractionated radiotherapy for esophageal carcinoma

    Purpose: To compare the treatment results and toxicity of continuous accelerated hyperfractionated (CAHF) and late-course accelerated hyperfractionated (LCAF) radiotherapy (RT) for esophageal carcinoma. Methods and Materials: Between August 1996 and March 1999, 101 patients with squamous cell carcinoma of the esophagus were randomized into two groups: 49 to the CAHF group and 52 to the LCAF group. Patients in the CAHF group received RT at 1.5 Gy/fraction b.i.d. (6-h interval), 5 d/wk, to a total dose 66 Gy in 44 fractions during 4.4 weeks. The patients in the LCAF group received conventional fractionation RT, 1.8 Gy/fraction, to a dose of 41.4 Gy in 23 fractions during 4.6 weeks, followed by accelerated fractionation RT using reduced fields, b.i.d., at 1.5 Gy/fraction, with a minimal interval of 6 h between fractions. The total dose was 68.4 Gy in 41 fraction during 6.4 weeks. Patient age, gender, performance score, diet, lesion location, lesion length, stage, and fractionation (CAHF or LCAF) were entered into the univariate and multivariate analyses. Results: All patients finished the treatment course, except for 1 patient in the CAHF group because of severe acute esophagitis. The rate of Grade I, II, and III acute bronchitis was 18.4% (9 of 49), 30.6% (15 of 49), and 8.2% (4 of 49) in the CAHF group and 13.5% (7 of 52), 21.2% (11 of 52), and 3.8% (2 of 52) in the LCAF group, respectively. However, the difference between the two groups was not statistically significant (p=0.084). The rate of Grade I, II, III, and IV acute esophagitis was 6.1% (3 of 49), 32.7% (16 of 49), 46.9% (23 of 49), and 14.3% (7 of 49) in the CAHF group and 26.9% (14 of 52), 32.7% (17 of 52), 7.7% (4 of 52), and 1.9% (1 of 52) in the LCAF group, respectively. The difference was statistically significant (p<0.001). The local control rate at 1, 2, and 3 years was 88.7%, 83.9%, and 55.9% in the CAHF group and 80.7%, 71.4%, and 57.1% in the LCAF group, respectively (p=0.1251). The 1-, 2-, and 3

  3. Accelerated ray tracing for radiotherapy dose calculations on a GPU

    M. de Greef; J. Crezee; J.C. van Eijk; R. Pool; A. Bel

    2009-01-01

    PURPOSE: The graphical processing unit (GPU) on modern graphics cards offers the possibility of accelerating arithmetically intensive tasks. By splitting the work into a large number of independent jobs, order-of-magnitude speedups are reported. In this article, the possible speedup of PLATO's ray t

  4. Study of the Accelerator Technology Development for Cancer Radiotherapy

    The hadronic particle beams including both protons, neutrons and charged particles have been studied for cancer therapy by a number of research centers in several countries during the past two decades. In this paper is briefly discussed concerning the accelerator type and its applications. The future trends are seen in the new technological developments like the use of proton gantries, beam scanning techniques, improved patient handling system and in the increasing precision of treatment. (author)

  5. The results of accelerated radiotherapy and concomitant cisplatin administration in advanced oropharyngeal cancer

    The accelerated radiotherapy and concomitant infusion of cisplatin in low doses was evaluated in 15 patients with advanced squamous cell carcinoma of the oral cavity and oral part of pharynx. Clinical complete response was seen in 6 of 15 patients (40%) and 4 patients (26.6%) were alive 12 months with no evidence of disease, of all group of 15 patients 9 (60%) were alive 12 months after treatment. (author)

  6. Physical-dosimetric enabling a dual linear accelerator 3D planning systems for radiotherapy

    The process of commissioning clinical linear accelerator requires a dual comprehensive study of the therapeutic beam parameters, both photons Electron. All information gained by measuring physical and dosimetric these beams must be analyzed, processed and refined for further modeling in computer-based treatment planning (RTPS). Of professionalism of this process will depend on the accuracy and precision of the calculations the prescribed doses. This paper aims to demonstrate availability clinical linear accelerator system-RTPS with late radiotherapy treatments shaped beam of photons and electrons. (author)

  7. Acceleration of pubertal development following pituitary radiotherapy for Cushing's disease

    Nicholl, R.M.; Kirk, J.M.W.; Grossman, A.B.; Plowman, P.N.; Besser, G.M.; Savage, M.O. (Saint Bartholomew' s Hospital, London (United Kingdom))

    1993-01-01

    A 7-year-old boy with pituitary dependent Cushing's disease was treated with pituitary irradiation following unsuccessful microadenomectomy. This led to normalization of the hypercortisolaemia, but was followed by GH deficiency. Two years after radiotherapy he had the onset of pubertal development with testicular enlargement to 8 ml bilaterally. Pubertal regression was induced using the long-acting GnRH analogue goserelin. Acceleration of skeletal maturation was also arrested, resulting in improvement of final height prediction. Irradiation directly to the hypothalamo-pituitary region, as well as whole brain irradiation, may thus be associated with accelerated pubertal development. (author).

  8. Radiotherapy

    This review highlights developments over the past decade in radiotherapy and attempts to summarize the state of the art in the management of the major diseases in which radiotherapy has a meaningful role. The equipment, radiobiology of radiotherapy and carcinoma of the lung, breast and intestines are highlighted

  9. TLD Intercomparison in accelerators for radiotherapy in three Latin american countries

    In Radiotherapy one of the objectives is to establish and to give follow up to quality assurance programs which make sure that the doses administered to the patients with cancer are a high probability of a success in external radiation. Likewise, one of the present preoccupations of the United Nations Agencies as well as the International Atomic Energy Agency and the Pan-American Health Organization is the optimal employment of the radiations in the treatment of cancer patients since the administered dose in Radiotherapy suffers considerable variations by the lack of quality assurance programs. The use of Electron linear accelerators requires a program of quality assurance that includes expert personnel, equipment and adequate facilities. The more used methodology for the dosimetry calibration and characterization of X-ray beams and high energy electrons for radiotherapy use is using a ionization chamber dosemeter calibrated in a regional secondary standardization laboratory. However, to establish and give follow up to the quality assurance programs it is necessary the dosimetric intercomparison through TLD. In this study it was designed plastic phantoms with TLD crystals and it was made its characterization to realize an absorbed dose analysis in the crystals exposed at X-ray beams 6 MV and high energy electrons 10 and 12 MeV to standardize the dosimetric procedures and proceeding to realize an International Pilot intercomparison of absorbed doses in TLD crystals in three Latin American countries: Mexico, Peru and Colombia with the participation of accelerators of five different institutions. The found results show that the majority of the measured doses with TLD in the different accelerators were in the 0.95-1.05 range though it had two cases outside of this range. The use of the phantoms with TLD crystals shows that they are of excellent aid to make analysis of the doses administered to the patients and an intercomparison of results to standardize procedures at

  10. Response of Hepatoma 9618a and Normal Liver to Host Carbogen and Carbon Monoxide Breathing

    Robinson, Simon P.; Loreta M. Rodrigues; Griffiths, John R.; Marion Stubbs

    1999-01-01

    The effects of hyperoxia (induced by host carbogen 95% oxygen/5% carbon dioxide breathing. and hypoxia (induced by host carbon monoxide CO at 660 ppm. breathing) were compared by using noninvasive magnetic resonance (MR) methods to gain simultaneous information on blood flow/oxygenation and the bioenergetic status of rat Morris H9618a hepatomas. Both carbogen and CO breathing induced a 1.5- to 2-fold increase in signal intensity in blood oxygenation level dependent (BOLD) MR images. This was ...

  11. Predictors for Clinical Outcomes After Accelerated Partial Breast Intensity-Modulated Radiotherapy

    Purpose: To correlate the treatment planning parameters with the clinical outcomes in patients treated with accelerated partial breast intensity-modulated radiotherapy. Methods and Materials: A total of 105 patients with Stage I breast cancer were treated between February 2004 and March 2007 in a Phase II prospective trial and had detailed information available on the planning target volume (PTV), ipsilateral breast volume (IBV), PTV/IBV ratio, lung volume, chest wall volume, surgery to radiotherapy interval, follow-up interval, breast pain, and cosmesis. The first 7 of these patients were treated to 34 Gy, and the remaining 98 were treated to 38.5 Gy. All patients were treated twice daily for 5 consecutive days. Univariate and multivariate analyses were performed. Results: The median follow-up was 13 months. No recurrences or deaths were observed. Of the 105 patients, 30 reported mild or moderate breast pain in their most recently recorded follow-up visit. The irradiated lung volume (p 35 Gy (p 35 Gy) and to lung correlated with reports of mild pain after accelerated partial breast intensity-modulated radiotherapy. Also, the PTV, but not the PTV/IBV ratio, was predictive of post-treatment reports of pain.

  12. Study on fluorescence properties of carbogenic nanoparticles and their application for the determination of ferrous succinate

    Sun Wen [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing 210009 (China); Du Yingxiang, E-mail: du_yingxiang@126.co [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing 210009 (China) and Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing 210009 (China) and Key Laboratory of Modern Chinese Medicines, Ministry of Education, China Pharmaceutical University, Nanjing 210009 (China); Wang Yunqing [Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China)

    2010-08-15

    A new type of fluorescent nanomaterial named carbogenic nanoparticles (NPs) has drawn considerable attention recently. In this study, we adopted a direct and simple synthetic method to produce the carbogenic NPs and investigated the fluorescence properties of the as-prepared carbogenic NPs in detail. It was found that the fluorescence of carbogenic NPs was stable with the variance of environmental conditions such as pH, temperature and UV irradiation. More interestingly, we found carbogenic NPs exhibited high selectivity and sensitivity towards ferric ions. Under optimum conditions, a good linear relationship could be obtained between the fluorescence intensity and concentration of ferric ions in the range of 5.0x10{sup -5}-5.0x10{sup -4} mol L{sup -1}, and the limit of detection is 11.2 {mu}mol L{sup -1}. Based on the fluorescence quenching of carbogenic NPs, a rapid and specific quantitative method was proposed for the determination of ferrous succinate. The content of ferrous succinate in commercial tablets determined by the present method was agreed with the spectrophotometric method results and the reproducibility and the recovery of the proposed method were satisfactory.

  13. Study on fluorescence properties of carbogenic nanoparticles and their application for the determination of ferrous succinate

    A new type of fluorescent nanomaterial named carbogenic nanoparticles (NPs) has drawn considerable attention recently. In this study, we adopted a direct and simple synthetic method to produce the carbogenic NPs and investigated the fluorescence properties of the as-prepared carbogenic NPs in detail. It was found that the fluorescence of carbogenic NPs was stable with the variance of environmental conditions such as pH, temperature and UV irradiation. More interestingly, we found carbogenic NPs exhibited high selectivity and sensitivity towards ferric ions. Under optimum conditions, a good linear relationship could be obtained between the fluorescence intensity and concentration of ferric ions in the range of 5.0x10-5-5.0x10-4 mol L-1, and the limit of detection is 11.2 μmol L-1. Based on the fluorescence quenching of carbogenic NPs, a rapid and specific quantitative method was proposed for the determination of ferrous succinate. The content of ferrous succinate in commercial tablets determined by the present method was agreed with the spectrophotometric method results and the reproducibility and the recovery of the proposed method were satisfactory.

  14. Response of Hepatoma 9618a and Normal Liver to Host Carbogen and Carbon Monoxide Breathing

    Simon P. Robinson

    1999-12-01

    Full Text Available The effects of hyperoxia (induced by host carbogen 95% oxygen/5% carbon dioxide breathing. and hypoxia (induced by host carbon monoxide CO at 660 ppm. breathing were compared by using noninvasive magnetic resonance (MR methods to gain simultaneous information on blood flow/oxygenation and the bioenergetic status of rat Morris H9618a hepatomas. Both carbogen and CO breathing induced a 1.5- to 2-fold increase in signal intensity in blood oxygenation level dependent (BOLD MR images. This was due to a decrease in deoxyhemoglobin (deoxyHb, which acts as an endogenous contrast agent, caused either by formation of oxyhemoglobin in the case of carbogen breathing, or carboxyhemoglobin with CO breathing. The results were confirmed by observation of similar changes in deoxyHb in arterial blood samples examined ex vivo after carbogen or CO breathing. There was no change in nucleoside triphosphates (NTP/PI in either tumor or liver after CO breathing, whereas NTP/Pl increased twofold in the hepatoma (but not in the liver after carbogen breathing. No changes in tumor intracellular pH were seen after either treatment, whereas extracellular pH became more alkaline after CO breathing and more acid after carbogen breathing, respectively. This tumor type and the liver are unaffected by CO breathing at 660 ppm, which implies an adequate oxygen supply.

  15. Randomized study on late course accelerated hyperfractionation radiotherapy plus cisplatin in the treatment of esophageal carcinomas

    Objective: To investigate the therapeutic results of late course accelerated hyperfractionation (LCAH) radiotherapy plus cisplatin as a radiosensitizer in the treatment of esophageal carcinoma. Methods: One hundred and four patients with squamou s cell carcinoma of the esophagus were randomized into two groups: LCAH alone group (53 patients) and LCAH + cisplatin group (51 patients). The same irradiation technique was given for both groups with conventional fractionation (2 Gy daily, 5 times a week) in the first 3 weeks and late course accelerated hyperfractionation (1.5 Cry twice daily, a minimum interfraction interval of 6 hours, 5 days per week) in the last 2 weeks. The total dose was 60 Gy/5 wks. In LCAH + cisplatin group, cisplatin was given simultaneous with 20 mg once daily for 5 days in the 1st and 5th weeks. The acute and late side effects were evaluated during :and after the treatment. Results: The median survival time was 12.2 months and 17.0 months in the LCAH alone group and LCAH + cisplatin group. The 1- and 3-year survival rates in LCAH group were 52.8 % and 20.8%; while those of LCAH + cisplatin group were 58.0 % and 24.0% (P>0.05). The acute gastrointestinal toxicities and hematological toxicities were obvious in LCAH + cisplatin group, but no increased acute esophagitis or late complications was observed. Conclusions: Late course accelerated hyperfractionation radio-therapy used simultaneously with cisplatin tends to increase the overall survival rate compared with the late course accelerated hyperfractionation radiotherapy alone in the treatment of esophageal carcinoma. (authors)

  16. Late course accelerated hyperfractionated radiotherapy for clinical T1-2 esophageal carcinoma

    Kuai-Le Zhao; Yang Wang; Xue-Hui Shi

    2003-01-01

    AIM: This retrospective study was designed to analyze the results and the failure patterns of late course accelerated hyperfractionated radiotherapy for clinical T1-2NoMo esophageal carcinoma. METHODS: From Aug. 1994 to Feb. 2001, 56 patients with clinical T1-2 esophageal carcinoma received late course accelerated hyperfractionated radiotherapy in Cancer Hospital,Fudan University. All patients had been histologically proven to have squamous cell carcinoma (SCC) and were diagnosed to be T1-2NoMo by CT scan. All patients were treated with conventional fractionation (CF) irradiation during the first twothirds course of the treatment to a dose of about 41.4Gy/23fx/4 to 5 weeks, Which was then followed by accelerated hyperfractionation irradiation using reduced fields, twice daily at 1.SGy per fraction, to a dose about 27Gy/18 fx. Thus the total dose was 67-70Gy/40-43fx/40-49 d. RESULTS: The 1-, 3- and 5-year overall survival was 90.9 %,54.6 %, 47.8 % respectively. The 1-, 3- and 5-year local control rate was 90.9 %, 84.5 % and 84.5 %, respectively.Twenty-five percent (14/56) patients had distant metastasis and/or lymph nodes metastasis alone. Eight point nine percent (5/56) patients had local disease alone. Another 3.6 % (2/56) patients had regional relapse and distant metastasis. CONCLUSION: Late course accelerated hyperfractionated radiotherapy is effective on clinical T1-2 esophageal carcinoma.The main failure pattern is distant metastasis.

  17. Toshiba's accelerator technology and approach toward higher performance and downsizing for heavy-ion radiotherapy

    Toshiba has developed various systems and components for particle beam accelerators, and delivered a number of accelerator systems including for SPring-8, which is the world's largest-class synchrotron radiation facility, as well as for the Central Japan Synchrotron Radiation Facility (provisional name). Combining our proprietary technologies cultivated through our experience in the development of particle beam accelerators, we are promoting the development of an accelerator for heavy-ion radiotherapy. Toward the higher performance and downsizing of its accelerator, we are also focusing on the research and development of both an ion source applying laser beam technologies, and a superconducting deflecting magnet for accelerators. (author)

  18. Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy

    Stiebel-Kalish, Hadas, E-mail: kalishhadas@gmail.com [Neuro-Ophthalmology Unit, Rabin Medical Center, Petah Tikva (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Reich, Ehud [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Ophthalmology, Rabin Medical Center, Petah Tikva (Israel); Gal, Lior [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Rappaport, Zvi Harry [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Neurosurgery, Rabin Medical Center, Petah Tikva (Israel); Nissim, Ouzi [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel); Pfeffer, Raphael [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Spiegelmann, Roberto [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel)

    2012-02-01

    Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up at our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.

  19. Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy

    Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up at our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.

  20. A real time scintillating fiber dosimeter for gamma and neutron monitoring on radiotherapy accelerators

    Bartesaghi, G. [INFN Sez. di Milano and Universita dell' Insubria, Como (Italy)]. E-mail: giacomobartesaghi@libero.it; Conti, V. [INFN Sez. di Milano and Universita dell' Insubria, Como (Italy); Prest, M. [INFN Sez. di Milano and Universita dell' Insubria, Como (Italy); Mascagna, V. [Universita dell' Insubria, Como (Italy); Scazzi, S. [Universita dell' Insubria, Como (Italy); Cappelletti, P. [Ospedale Sant' Anna, Como (Italy); Frigerio, M. [Ospedale Sant' Anna, Como (Italy); Gelosa, S. [Ospedale Sant' Anna, Como (Italy); Monti, A. [Ospedale Sant' Anna, Como (Italy); Ostinelli, A. [Ospedale Sant' Anna, Como (Italy); Mozzanica, A. [INFN Sez. di Pavia and Universita di Brescia (Italy); Bevilacqua, R. [Universita di Trieste and INFN sez. di Trieste (Italy); Giannini, G. [Universita di Trieste and INFN sez. di Trieste (Italy); Totaro, P. [Universita di Trieste and INFN sez. di Trieste (Italy); Vallazza, E. [INFN Sez. di Trieste (Italy)

    2007-03-01

    The quality of the radiotherapic treatment depends strongly on the capability to measure the dose released in the treated volume and the one absorbed by the surrounding volumes, which is mainly due to the scattered radiation produced by the primary beam interaction with the accelerator collimating system. Radiotherapy linear accelerators produce electron (6-20MeV) and photon (6, 18MV) irradiating fields up to 40x40cm{sup 2}. Photons with energies greater than 8MeV generate neutrons via photoproduction which are being studied for possible BNCT applications. We have developed a prototype of a real time dosimeter with 1mm diameter scintillating and clear fibers readout by multianode photomultipliers. For neutron applications, the fibers have been coupled with boron loaded scintillator. We will describe the dosimeter and the results of the tests comparing them to the ones obtained with the standard dosimeters.

  1. Vertical mammaplasty associated with accelerated partial breast radiotherapy: how oncoplastic surgery techniques associated with modern techniques of radiotherapy can improve the aesthetic outcome in selected patients

    Breast cancer is the second most common type of cancer in the world, being the most common among women, responsible for 22% of new cases each year. It's surgical and radiation treatment evolved from radical procedures (Halsted radical mastectomy and total external breast radiotherapy) to less radical and more conservative procedures. With the use of modern oncoplastic surgery techniques and accelerated partial breast radiotherapy, selected patients can benefit with better aesthetic results, fewer side effects, and more comfortable and brief treatments. (author)

  2. Vertical mammaplasty associated with accelerated partial breast radiotherapy: how oncoplastic surgery techniques associated with modern techniques of radiotherapy can improve the aesthetic outcome in selected patients

    Couto, Henrique Lima, E-mail: enriquecouto@hotmail.com [Santa Fe Women' s and Maternity Hospital, Belo Horizonte, MG (Brazil); Amorim, Washington Cancado; Guimaraes, Rodrigo [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Hospital Geral; Ramires, Leandro Cruz; Castilho, Marcus Simoes [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Fac. de Medicina; Dominguez, Lorena Lima Coto [Universidade Estacio de Sa (UNESA), Rio de Janeiro, EJ (Brazil)

    2014-07-15

    Breast cancer is the second most common type of cancer in the world, being the most common among women, responsible for 22% of new cases each year. It's surgical and radiation treatment evolved from radical procedures (Halsted radical mastectomy and total external breast radiotherapy) to less radical and more conservative procedures. With the use of modern oncoplastic surgery techniques and accelerated partial breast radiotherapy, selected patients can benefit with better aesthetic results, fewer side effects, and more comfortable and brief treatments. (author)

  3. Hyperfractionated-accelerated radiotherapy followed by radical surgery in locally advanced tumors of the oral cavity

    Hoeller, U. [Dept. of Radiotherapy, Radiooncology and Nuclear Medicine, Vivantes Klinikum Neukoelln, Berlin (Germany); Biertz, I.; Tribius, S.; Alberti, W. [Dept. of Radiotherapy and Radiooncology, Univ. Hospital Hamburg-Eppendorf (Germany); Flinzberg, S.; Schmelzle, R. [Dept. of Dental, Oral and Maxillofacial Surgery, Univ. Hospital Hamburg-Eppendorf (Germany)

    2006-03-15

    Purpose: to evaluate the outcome of hyperfractionated-accelerated radiotherapy and subsequent planned primary tumor resection and radical neck dissection in locally advanced tumors of the oral cavity. Patients and Methods: this retrospective analysis evaluates 126 subsequent patients who were treated between 1988 and 1997 for locally advanced tumors of the oral cavity (with extension into the oropharynx in 17 patients), 34 (27%) AJCC stage III and 92 (73%) stage IV. Primary tumor and nodal metastases were irradiated with 1.4 Gy bid to a median total dose of 72.8 Gy (range 58.8-75.6 Gy). Then, planned radical surgery of the primary site according to the initial tumor extent and cervical nodes was performed. Median follow-up of living patients was 6 years (range 1-11 years). Results: 4 weeks after radiotherapy, 14 patients (11%) had complete tumor remission, 92 (73%) partial remission, 15 (12%) no change, and five (4%) progressive disease. Complete resection was achieved in 117 (93%) patients (nine incomplete resections). 5-year locoregional control rate was 62 {+-} 9%, overall survival 36 {+-} 9%. Surgery-related morbidity occurred in 42 patients (33%; mainly delayed wound healing and fistulae), overall severe treatment-related morbidity in 46 patients (36%). 24/84 relapse-free patients (29%) required a percutaneous gastrostomy or nasal tube {>=} 1 year after therapy. Conclusion: in this study, the outcome of combined curative radiotherapy and planned surgery of the primary tumor and neck nodes was comparable to reported results of hyperfractionated radiotherapy with or without salvage surgery of the neck nodes with respect to locoregional control and overall survival. Planned surgery carries a substantial risk of morbidity and seems to offer no benefit in comparison to salvage surgery of the neck nodes only. Therefore, salvage surgery is preferred. (orig.)

  4. Carbogen inhalation increases oxygen transport to hypoperfused brain tissue in patients with occlusive carotid artery disease: increased oxygen transport to hypoperfused brain

    Ashkanian, Mahmoud; Gjedde, Albert; Mouridsen, Kim;

    2009-01-01

    Sa(O2) are readily obtained with carbogen, while oxygen increases only Sa(O2). Thus, carbogen improves oxygen transport to brain tissue more efficiently than oxygen alone. Further studies with more subjects are, however, needed to investigate the applicability of carbogen for long-term inhalation and...

  5. Prostate stereotactic ablative body radiotherapy using a standard linear accelerator: Toxicity, biochemical, and pathological outcomes

    Background and purpose: Biological dose escalation through stereotactic ablative radiotherapy (SABR) holds promise of improved patient convenience, system capacity and tumor control with decreased cost and side effects. The objectives are to report the toxicities, biochemical and pathologic outcomes of this prospective study. Materials and methods: A phase I/II study was performed where low risk localized prostate cancer received SABR 35 Gy in 5 fractions, once weekly on standard linear accelerators. Common Terminology Criteria for Adverse Events v3.0 and Radiation Therapy Oncology Group late morbidity scores were used to assess acute and late toxicities, respectively. Biochemical control (BC) was defined by the Phoenix definition. Results: As of May 2012, 84 patients have completed treatment with a median follow-up of 55 months (range 13–68 months). Median age was 67 years and median PSA was 5.3 ng/ml. The following toxicities were observed: acute grade 3+: 0% gastrointestinal (GI), 1% genitourinary (GU), 0% fatigue; late grade 3+: 1% GI, 1% GU. Ninety-six percent were biopsy negative post-treatment. The 5-year BC was 98%. Conclusions: This novel technique employing standard linear accelerators to deliver an extreme hypofractionated schedule of radiotherapy is feasible, well tolerated and shows excellent pathologic and biochemical control

  6. Transient perfusion and radiosensitizing effect after nicotinamide, carbogen, and perflubron emulsion administration

    In order to improve the effect of radiation on tumour response, nicotinamide, perflubron emulsion and carbogen were administered which act on both diffusion limited hypoxia and intermittent perfusion limited hypoxia. These treatments were used in different combinations. The maximal radiosensitizing effect was found with the combination of the three treatments. The aim of this study was to use a double staining method (Hoechst 33342 and DiOC7(3)) to evaluate the influence of nicotinamide, perflubron emulsion and carbogen on transient perfusion in three tumour cell lines transplanted onto nude mice: one rodent (EMT6), two human (HRT18, a rectal adenocarcinoma; and Na11+, a melanoma). For untreated groups, the percentage of closed and mismatched vessels depended on the tumour cell line. Carbogen alone or carbogen plus perflubron emulsion decreased the number of mismatched and closed vessels only for the two human cell lines. Nicotinamide was effective in decreasing the percentage of mismatched and closed vessels only for the melanoma cell line. The combination of nicotinamide, carbogen and perflubron emulsion was the most effective at decreasing both percentage of mismatched and closed vessels in all three tumours studies. This combination was also the most effective at enhancing the radiation response in all three tumours

  7. Effects of hyperbaric oxygen and normobaric carbogen on the radiation response of the rat rhabdomyosarcoma R1H

    Purpose: Hypoxic tumor cells are an important factor of radioresistance. Hyperbaric oxygen (HBO) and normobaric carbogen (95% oxygen, 5% carbon dioxide) increase the oxygen delivery to tumors. This study was performed to explore changes of tumor oxygenation during a course of fractionated irradiation and to determine the effectiveness of normobaric carbogen and HBO during the final phase of the radiation treatment. Methods and Materials: Experiments were performed on the rhabdomyosarcoma R1H growing on WAG/Rij rats. After 20 X-ray fractions of 2 Gy within 4 weeks, oxygen partial pressure (pO2) was measured using the Eppendorf oxygen electrode under ambient conditions, with normobaric carbogen or HBO at a pressure of 240 kPa. Following the 4-week radiation course, a top-up dose of 10-50 Gy was applied in 2-10 fractions of 5 Gy with or without hyperoxygenation. Results: HBO but not carbogen significantly increased the median pO2 in irradiated tumors. The radiation doses to control 50% of tumors were 38.0 Gy, 29.5 Gy, and 25.0 Gy for air, carbogen, and HBO, respectively. Both high oxygen content gas inspirations led to significantly improved tumor responses with oxygen enhancement ratios (OERs) of 1.3 for normobaric carbogen and 1.5 for HBO (air vs. carbogen: p=0.044; air vs. HBO: p=0.02; carbogen vs. HBO: p=0.048). Conclusion: Both normobaric carbogen and HBO significantly improved the radiation response of R1H tumors. HBO appeared to be more effective than normobaric carbogen, both with regard to tumor oxygenation and response to irradiation

  8. Correlation between egfr expression and accelerated proliferation during radiotherapy of head and neck squamous cell carcinoma

    Pedicini Piernicola

    2012-08-01

    Full Text Available Abstract Purpose To investigate the correlation between the expression of Epidermal Growth Factor receptor (EGFr and the reduction of the effective doubling time (TD during radiotherapy treatment and also to determine the dose per fraction to be taken into account when the overall treatment time (OTT is reduced in accelerated radiotherapy of head and neck squamous cell carcinoma (HNSCC. Methods A survey of the published papers comparing 3-years of local regional control rate (LCR for a total of 2162 patients treated with conventional and accelerated radiotherapy and with a pretreatment assessment of EGFr expression, was made. Different values of TD were obtained by a model incorporating the overall time corrected biologically effective dose (BED and a 3-year clinical LCR for high and low EGFr groups of patients (HEGFr and LEGFr, respectively. By obtaining the TD from the above analysis and the sub-sites’ potential doubling time (Tpot from flow cytometry and immunohistochemical methods, we were able to estimate the average TD for each sub-site included in the analysis. Moreover, the dose that would be required to offset the modified proliferation occurring in one day (Dprolif, was estimated. Results The averages of TD were 77 (27-9095% days in LEGFr and 8.8 (7.3-11.095% days in HEGFr, if an onset of accelerated proliferation TK at day 21 was assumed. The correspondent HEGFr sub-sites’ TD were 5.9 (6.6, 5.9 (6.6, 4.6 (6.1, 14.3 (12.9 days, with respect to literature immunohistochemical (flow cytometry data of Tpot for Oral-Cavity, Oro-pharynx, Hypo-pharynx, and Larynx respectively. The Dprolif for the HEGFr groups were 0.33 (0.29, 0.33 (0.29, 0.42 (0.31, 0.14 (0.15 Gy/day if α = 0.3 Gy-1 and α/β = 10 Gy were assumed. Conclusions A higher expression of the EGFr leads to enhanced proliferation. This study allowed to quantify the extent of the effect which EGFr expression has in terms of reduced TD and Dprolif for each head and neck

  9. Toxicity and cosmetic outcome of three-dimensional conformal radiotherapy for accelerated partial breast irradiation

    Gatti, M.; Bresciani, S.; Ponzone, R.; Panaia, R.; Salatino, A.; Stasi, M.; Gabriele, P. [IRCC, Candiolo (Italy)

    2011-10-15

    Full text of publication follows: Purpose.- To analyse the incidence and severity of acute and late normal tissue toxicity and cosmetic outcome using three - dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Patients and Methods.- 70 patients with stage I disease were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation, in an approved protocol. The prescribed dose was 34 Gy in all patients delivered in 10 fractions over 5 consecutive days. On all CT scans gross tumor volume (GTV ) was defined around surgical clips. A 1.5 cm margin was added in order to account for clinical target volume (CTV) . A margin of 1 cm was added to CTI to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the specifications as dictated in the NSABP/RTOG protocol. After treatment, patients underwent a clinical and cosmetic evaluation every 3 months. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed by the physicians using the controlateral untreated breast as the reference (Harvard scale). Results.- Median patient age was 66 years (range 51-80). Median follow-up was 15 months (range 6-46). Tumor size was < 10 mm in 33 patients (53%) and > 2 cm in 4(6%). The mean value of the ratio between the PTV and the whole ipsilateral breast volume was 38 % and the median percentage whole breast volume that received 95 % of prescribed dose was 34% (range 16%-55%). The rate of G1 and G2 acute skin toxicity was 28% and 2% respectively and the late toxicity was 17% (G1). G2 or greater toxicities were not observed. The most pronounced G1 late toxicity was subcutaneous fibrosis, developed in 3 patients. The cosmetic outcome was excellent in 83% and good in 17%. Conclusion.- Accelerated partial breast irradiation using three-dimensional conformal radiotherapy is technically feasible with very low acute and late toxicity. Long

  10. Correlation between egfr expression and accelerated proliferation during radiotherapy of head and neck squamous cell carcinoma

    To investigate the correlation between the expression of Epidermal Growth Factor receptor (EGFr) and the reduction of the effective doubling time (TD) during radiotherapy treatment and also to determine the dose per fraction to be taken into account when the overall treatment time (OTT) is reduced in accelerated radiotherapy of head and neck squamous cell carcinoma (HNSCC). A survey of the published papers comparing 3-years of local regional control rate (LCR) for a total of 2162 patients treated with conventional and accelerated radiotherapy and with a pretreatment assessment of EGFr expression, was made. Different values of TD were obtained by a model incorporating the overall time corrected biologically effective dose (BED) and a 3-year clinical LCR for high and low EGFr groups of patients (HEGFr and LEGFr), respectively. By obtaining the TD from the above analysis and the sub-sites’ potential doubling time (Tpot) from flow cytometry and immunohistochemical methods, we were able to estimate the average TD for each sub-site included in the analysis. Moreover, the dose that would be required to offset the modified proliferation occurring in one day (Dprolif), was estimated. The averages of TD were 77 (27-90)95% days in LEGFr and 8.8 (7.3-11.0)95% days in HEGFr, if an onset of accelerated proliferation TK at day 21 was assumed. The correspondent HEGFr sub-sites’ TD were 5.9 (6.6), 5.9 (6.6), 4.6 (6.1), 14.3 (12.9) days, with respect to literature immunohistochemical (flow cytometry) data of Tpot for Oral-Cavity, Oro-pharynx, Hypo-pharynx, and Larynx respectively. The Dprolif for the HEGFr groups were 0.33 (0.29), 0.33 (0.29), 0.42 (0.31), 0.14 (0.15) Gy/day if α = 0.3 Gy-1 and α/β = 10 Gy were assumed. A higher expression of the EGFr leads to enhanced proliferation. This study allowed to quantify the extent of the effect which EGFr expression has in terms of reduced TD and Dprolif for each head and neck sub-site

  11. Toxicity and cosmetic outcome of three-dimensional conformal radiotherapy for accelerated partial breast irradiation

    Full text of publication follows: Purpose.- To analyse the incidence and severity of acute and late normal tissue toxicity and cosmetic outcome using three - dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Patients and Methods.- 70 patients with stage I disease were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation, in an approved protocol. The prescribed dose was 34 Gy in all patients delivered in 10 fractions over 5 consecutive days. On all CT scans gross tumor volume (GTV ) was defined around surgical clips. A 1.5 cm margin was added in order to account for clinical target volume (CTV) . A margin of 1 cm was added to CTI to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the specifications as dictated in the NSABP/RTOG protocol. After treatment, patients underwent a clinical and cosmetic evaluation every 3 months. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed by the physicians using the controlateral untreated breast as the reference (Harvard scale). Results.- Median patient age was 66 years (range 51-80). Median follow-up was 15 months (range 6-46). Tumor size was 2 cm in 4(6%). The mean value of the ratio between the PTV and the whole ipsilateral breast volume was 38 % and the median percentage whole breast volume that received 95 % of prescribed dose was 34% (range 16%-55%). The rate of G1 and G2 acute skin toxicity was 28% and 2% respectively and the late toxicity was 17% (G1). G2 or greater toxicities were not observed. The most pronounced G1 late toxicity was subcutaneous fibrosis, developed in 3 patients. The cosmetic outcome was excellent in 83% and good in 17%. Conclusion.- Accelerated partial breast irradiation using three-dimensional conformal radiotherapy is technically feasible with very low acute and late toxicity. Long-term results are needed to assess

  12. Accelerated superfractionated radiotherapy for inflammatory breast carcinoma: complete response predicts outcome and allows for breast conservation

    Purpose: Chemotherapy and accelerated superfractionated radiotherapy were prospectively applied for inflammatory breast carcinoma with the intent of breast conservation. The efficacy, failure patterns, and patient tolerance utilizing this approach were analyzed. Methods and Materials: Between 1983 and 1996, 52 patients with inflammatory breast carcinoma presented to the Medical College of Virginia Hospitals of VCU and the New England Medical Center. Thirty-eight of these patients were jointly evaluated in multidisciplinary breast clinics and managed according to a defined prospectively applied treatment policy. Patients received induction chemotherapy, accelerated superfractionated radiotherapy, selected use of mastectomy, and concluded with additional chemotherapy. The majority were treated with 1.5 Gy twice daily to field arrangements covering the entire breast and regional lymphatics. An additional 18-21 Gy was then delivered to the breast and clinically involved nodal regions. Total dose to clinically involved areas was 63-66 Gy. Following chemoradiotherapy, patients were evaluated with physical examination, mammogram, and fine needle aspiration x 3. Mastectomy was reserved for those patients with evidence of persistent or progressive disease in the involved breast. All patients received additional chemotherapy. Results: Median age was 51 years. Median follow-up was 23.9 months (6-86) months. The breast preservation rate at the time of last follow-up was 74%. The treated breast or chest wall as the first site of failure occurred in only 13%, and the ultimate local control rate with the selected use of mastectomy was 74%. Ten patients underwent mastectomy, 2 of which had pathologically negative specimens despite a clinically palpable residual mass. Response to chemotherapy was predictive of treatment outcome. Of the 15 patients achieving a complete response, 87% remain locoregionally controlled without the use of mastectomy. Five-year overall survival for

  13. Quality of life in patients with oropharynx carcinomas: assessment after accelerated radiotherapy with or without chemotherapy versus radical surgery and postoperative radiotherapy

    Allal, Abdelkarim Said; Nicoucar, Kevin; Mach, Nicolas; Dulguerov, Pavel

    2003-01-01

    In oropharyngeal carcinomas, it is assumed that the effectiveness of the different treatment approaches is roughly equivalent, whereas the functional outcome after radical radiotherapy (RT) is superior to that associated with primary surgery. The aim of this study is to assess quality of life (QoL) outcomes of patients after two treatment strategies: radical surgery with postoperative RT and accelerated concomitant boost RT with or without chemotherapy.

  14. Radiotherapy

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy

  15. Preoperative concurrent CBDCA chemotherapy and accelerated hyperfractionated radiotherapy for squamous cell carcinoma of the maxillary region

    Between 1994 and 2000, 28 patients with T3/T4 squamus cell carcinoma of the maxillary region (maxillary sinus, 22; maxillary gingiva, 4; maxillary bone, 1; buccal mucosa, 1) had accelerated hyperfractionated radiotherapy combined with simultaneous CBDCA chemotherapy preoperatively, at Chiba Cancer Center Hospital. The protocol consisted of combined therapy with accelerated hyperfractionated irradiation of 1.6 Gy, twice a day, to a total dose of 32.0-51.2 Gy and concurrent intra-arterial or intravenous infusion of CBDCA 20-30 mg/body/day for a cumulative total dose of 270-480 mg. After completion of the preoperative combined therapy, the clinical CR rate was 17.9%, and the good PR·CR rate was 32.1%. According to the initial findings and response to the combined therapy, all patients had maxillectomy (subtotal, 3; total, 16; extended, 9) 4 weeks after completion of the preoperative combined therapy. Postoperatively, the complete pathologic response (Ohboshi and Shimozato's classification, grade III and IV) rate was 28.6%. And the actuarial local control rate was 85.7%, with a mean follow-up of 46.2 months. Based on these results, we believe this preoperative therapy with CBDCA chemotherapy and accelerated hyperfractionated radiation is a significant choice as treatment for squamous cell cancer of the maxillary region. (author)

  16. Effectiveness of custom neutron shielding in the maze of radiotherapy accelerators

    An investigation was performed to examine the neutron dose equivalent in a radiotherapy maze lined with a customised neutron shielding material. The accelerator investigated was a Varian Clinac 2100C/D using 18 MV photons, and the neutron shielding utilised at this centre was PremadexTM commercially available neutron shielding. Based on Monte Carlo simulations, properly installed customised neutron shielding may reduce the neutron dose equivalent by up to a factor of 8 outside the maze, depending upon the installation. In addition, it was determined that the neutron dose near the entrance to the maze may be reduced by approximately 40% by using customised neutron shielding in the maze, as compared with a facility not using this shielding. This would have a positive dose-saving effect in doorless maze designs. (author)

  17. Challenges in Linear Accelerator Radiotherapy for Chordomas and Chondrosarcomas of the Skull Base: Focus on Complications

    Hauptman, Jason S., E-mail: jhauptman@mednet.ucla.edu [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Barkhoudarian, Garni; Safaee, Michael; Gorgulho, Alessandra [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Tenn, Steven; Agazaryan, Nzhde; Selch, Michael [Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); De Salles, Antonio A.F. [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States)

    2012-06-01

    Purpose: Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that infiltrate the skull base. Currently, consensus therapy includes surgical resection and adjuvant radiotherapy. Radiation delivery is typically limited by the proximity of these tumors to critical skull base structures. Methods: This is a retrospective review of 13 cases of chordomas and 2 cases of chondroid chondrosarcomas of the skull based treated with linear accelerator stereotactic radiotherapy (SRT, n = 10) or stereotactic radiosurgery (SRS, n = 5). The average time to the most recent follow-up visit was 4.5 years. The tumor characteristics, treatment details, and outcomes were recorded. Each radiation plan was reviewed, and the dosage received by the brainstem, optic apparatus, and pituitary was calculated. Results: Of the 10 patients treated with SRT, 6 were found to have unchanged or decreased tumor size as determined from radiographic follow-up. Of the 5 patients treated with SRS, 3 were found to have stable or unchanged tumors at follow-up. The complications included 1 SRT patient who developed endocrinopathy, 2 patients (1 treated with SRS and the other with SRT), who developed cranial neuropathy, and 1 SRS patient who developed visual deficits. Additionally, 1 patient who received both SRS and SRT within 2 years for recurrence experienced transient medial temporal lobe radiation changes that resolved. Conclusions: Where proton beam therapy is unavailable, linear accelerator-based SRT or radiosurgery remains a safe option for adjuvant therapy of chordomas and chondrosarcomas of the skull base. The exposure of the optic apparatus, pituitary stalk, and brainstem must be considered during planning to minimize complications. If the optic apparatus is included in the 80% isodose line, it might be best to fractionate therapy. Exposure of the pituitary stalk should be kept to <30 Gy to minimize endocrine dysfunction. Brainstem exposure should be

  18. Accelerated radiotherapy for T1, 2 glottic carcinoma: analysis of results with KI-67 index

    Purpose: Hyperfractionated and accelerated radiotherapy without a split was performed to improve the local control probability of early glottic carcinomas. We analyzed the results of this regimen by using the Ki-67 index. Methods and Materials: Over a 12-year period, 85 T1N0M0 glottic cancers and 50 T2N0M0 glottic cancers were treated with conventional fractionation (CF) from 1984 to 1989 and with accelerated fractionation (AF) since 1990. The CF program consisted of five daily fractions of 2 Gy per week, for a total of 64 Gy. The AF program consisted of 1.72 Gy per fraction, two fractions per day, 5 days a week, for a total of 55 or 58 Gy. The specimens, taken before radiotherapy, were immunohistochemically stained with anti-Ki-67 antibody. Results: The 5-year local control probability for T1 tumors was 79.6 ± 6.9% with CF treatment, whereas with AF it was 86.9 ± 5.6%. For T2 tumors it was 62.7 ± 12.2% with CF, whereas it was 74.7 ± 7.8% with AF. The difference between CF and AF did not reach the point of statistical significance. However, when T1 tumors had a Ki-67 index lower than 50%, the local control rate achieved with AF was significantly better than that with CF (p = 0.018). When the tumors had a Ki-67 index that was 50% or more, there was no difference in the local control rate between CF and AF, whether they were T1 or T2. The peak mucosal reactions at the larynx and/or hypopharynx were much more severe and appeared at smaller doses and earlier in AF than in CF. The patients with AF showed no severe late complications. Conclusions: AF could not obtain statistically significant improvement in local control probability of T1 or T2 glottic carcinomas

  19. Challenges in Linear Accelerator Radiotherapy for Chordomas and Chondrosarcomas of the Skull Base: Focus on Complications

    Purpose: Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that infiltrate the skull base. Currently, consensus therapy includes surgical resection and adjuvant radiotherapy. Radiation delivery is typically limited by the proximity of these tumors to critical skull base structures. Methods: This is a retrospective review of 13 cases of chordomas and 2 cases of chondroid chondrosarcomas of the skull based treated with linear accelerator stereotactic radiotherapy (SRT, n = 10) or stereotactic radiosurgery (SRS, n = 5). The average time to the most recent follow-up visit was 4.5 years. The tumor characteristics, treatment details, and outcomes were recorded. Each radiation plan was reviewed, and the dosage received by the brainstem, optic apparatus, and pituitary was calculated. Results: Of the 10 patients treated with SRT, 6 were found to have unchanged or decreased tumor size as determined from radiographic follow-up. Of the 5 patients treated with SRS, 3 were found to have stable or unchanged tumors at follow-up. The complications included 1 SRT patient who developed endocrinopathy, 2 patients (1 treated with SRS and the other with SRT), who developed cranial neuropathy, and 1 SRS patient who developed visual deficits. Additionally, 1 patient who received both SRS and SRT within 2 years for recurrence experienced transient medial temporal lobe radiation changes that resolved. Conclusions: Where proton beam therapy is unavailable, linear accelerator-based SRT or radiosurgery remains a safe option for adjuvant therapy of chordomas and chondrosarcomas of the skull base. The exposure of the optic apparatus, pituitary stalk, and brainstem must be considered during planning to minimize complications. If the optic apparatus is included in the 80% isodose line, it might be best to fractionate therapy. Exposure of the pituitary stalk should be kept to <30 Gy to minimize endocrine dysfunction. Brainstem exposure should be

  20. Five Year Outcome of 145 Patients With Ductal Carcinoma In Situ (DCIS) After Accelerated Breast Radiotherapy

    Ciervide, Raquel [Department of Radiation Oncology, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States); Dhage, Shubhada; Guth, Amber; Shapiro, Richard L.; Axelrod, Deborah M.; Roses, Daniel F. [Department of Surgery, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States); Formenti, Silvia C., E-mail: silvia.formenti@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, NYU Langone Medical Center, New York, New York (United States)

    2012-06-01

    Background: Accelerated whole-breast radiotherapy (RT) with tumor bed boost in the treatment of early invasive breast cancer has demonstrated equivalent local control and cosmesis when compared with standard RT. Its efficacy in the treatment of ductal carcinoma in situ (DCIS) remains unknown. Methods and Materials: Patients treated for DCIS with lumpectomy and negative margins were eligible for 2 consecutive hypofractionated whole-breast RT clinical trials. The first trial (New York University [NYU] 01-51) prescribed to the whole breast 42 Gy (2.8 Gy in 15 fractions) and the second trial (NYU 05-181) 40.5 Gy (2.7 Gy in 15 fractions) with an additional daily boost of 0.5 Gy to the surgical cavity. Results: Between 2002 and 2009, 145 DCIS patients accrued, 59 to the first protocol and 86 to the second trial. Median age was 56 years and 65% were postmenopausal at the time of treatment. Based on optimal sparing of normal tissue, 79% of the patients were planned and treated prone and 21% supine. At 5 years' median follow-up (60 months; range 2.6-105.5 months), 6 patients (4.1%) experienced an ipsilateral breast recurrence in all cases of DCIS histology. In 3/6 patients, recurrence occurred at the original site of DCIS and in the remaining 3 cases outside the original tumor bed. New contralateral breast cancers arose in 3 cases (1 DCIS and 2 invasive carcinomas). Cosmetic self-assessment at least 2 years after treatment is available in 125 patients: 91% reported good-to-excellent and 9% reported fair-to-poor outcomes. Conclusions: With a median follow-up of 5 years, the ipsilateral local recurrence rate is 4.1%, comparable to that reported from the NSABP (National Surgical Adjuvant Breast and Bowel Project) trials that employed 50 Gy in 25 fractions of radiotherapy for DCIS. There were no invasive recurrences. These results provide preliminary evidence that accelerated hypofractionated external beam radiotherapy is a viable option for DCIS.

  1. Five Year Outcome of 145 Patients With Ductal Carcinoma In Situ (DCIS) After Accelerated Breast Radiotherapy

    Background: Accelerated whole-breast radiotherapy (RT) with tumor bed boost in the treatment of early invasive breast cancer has demonstrated equivalent local control and cosmesis when compared with standard RT. Its efficacy in the treatment of ductal carcinoma in situ (DCIS) remains unknown. Methods and Materials: Patients treated for DCIS with lumpectomy and negative margins were eligible for 2 consecutive hypofractionated whole-breast RT clinical trials. The first trial (New York University [NYU] 01-51) prescribed to the whole breast 42 Gy (2.8 Gy in 15 fractions) and the second trial (NYU 05-181) 40.5 Gy (2.7 Gy in 15 fractions) with an additional daily boost of 0.5 Gy to the surgical cavity. Results: Between 2002 and 2009, 145 DCIS patients accrued, 59 to the first protocol and 86 to the second trial. Median age was 56 years and 65% were postmenopausal at the time of treatment. Based on optimal sparing of normal tissue, 79% of the patients were planned and treated prone and 21% supine. At 5 years' median follow-up (60 months; range 2.6-105.5 months), 6 patients (4.1%) experienced an ipsilateral breast recurrence in all cases of DCIS histology. In 3/6 patients, recurrence occurred at the original site of DCIS and in the remaining 3 cases outside the original tumor bed. New contralateral breast cancers arose in 3 cases (1 DCIS and 2 invasive carcinomas). Cosmetic self-assessment at least 2 years after treatment is available in 125 patients: 91% reported good-to-excellent and 9% reported fair-to-poor outcomes. Conclusions: With a median follow-up of 5 years, the ipsilateral local recurrence rate is 4.1%, comparable to that reported from the NSABP (National Surgical Adjuvant Breast and Bowel Project) trials that employed 50 Gy in 25 fractions of radiotherapy for DCIS. There were no invasive recurrences. These results provide preliminary evidence that accelerated hypofractionated external beam radiotherapy is a viable option for DCIS.

  2. Procedure to measure the neutrons spectrum around a lineal accelerator for radiotherapy

    An experimental procedure was developed, by means of Bonner spheres, to measure the neutrons spectrum around Linacs of medical use that only requires of a single shot of the accelerator; to this procedure we denominate Planetary or Isocentric method. One of the problems associated to the neutrons spectrum measurement in a radiotherapy room with lineal accelerator is because inside the room a mixed, intense and pulsed radiation field takes place affecting the detection systems based on active detector; this situation is solved using a passive detector. In the case of the Bonner spheres spectrometer the active detector has been substituted by activation detectors, trace detectors or thermoluminescent dosimeters. This spectrometer uses several spheres that are situated one at a time in the measurement point, this way to have the complete measurements group the accelerator should be operated, under the same conditions, so many times like spheres have the spectrometer, this activity can consume a long time and in occasions due to the work load of Linac to complicate the measurement process too. The procedure developed in this work consisted on to situate all the spectrometer spheres at the same time and to make the reading by means of a single shot, to be able to apply this procedure, is necessary that before the measurements two characteristics are evaluated: the cross-talking of the spheres and the symmetry conditions of the neutron field. This method has been applied to determine the photo-neutrons spectrum produced by a lineal accelerator of medical use Varian ix of 15 MV to 100 cm of the isocenter located to 5 cm of depth of a solid water mannequin of 30 x 30 x 15 cm. The spectrum was used to determine the total flow and the environmental dose equivalent. (Author)

  3. Radiotherapy

    The need for radiotherapy research is exemplified by the 100,000 cancer patients who will fail treatment locally and/or regionally annually for the next several years but who would benefit from better local treatment modalities. Theoretically, all of the areas of investigation discussed in this projection paper have the potential to significantly improve local-regional treatment of cancer by radiotherapy alone or in combination with other modalities. In many of the areas of investigation discussed in this paper encouraging results have been obtained in cellular and animal tumor studies and in limited studies in humans as well. In the not too distant future the number of patients who would benefit from better local control may increase by tens of thousands if developments in chemotherapy and/or immunotherapy provide a means to eradicate disseminated microscopic foci of cancer. Thus the efforts to improve local-regional control take on even greater significance

  4. Alternating chemotherapy and hyperfractionated accelerated radiotherapy in non-metastatic inflammatory breast cancer; Radiotherapie hyperfractionnee acceleree alternee avec une chimiotherapie dans le cancer du sein inflammatoire non metastatique

    Hasbini, A.; Le Pechoux, C.; Roche, B.; Pignol, J.P.; Abdulkarim, B.; Habrand, J.L. [Institut Gustave Roussy, Dept. de Radiotherapie, 94 - Villejuif (France); Zelek, L.; Spielmann, M. [Institut Gustave Roussy, Dept. d' oncologie Medicale, 94 - Villejuif (France); Arriagada, R. [Instituto de Radiomedicina, IRAM, Santiago, (Chile); Guinebretiere, J.M. [Institut Gustave Roussy, Dept. d' Anatomopothologie, 94 - Villejuif (France); Tardivon, A. [Institut Gustave Roussy, Dept. de Radiodiagnostic, 94 - Villejuif (France)

    2000-08-01

    Based on encouraging results reported in alternating radiotherapy and chemotherapy in inflammatory breast carcinoma, we have tried in this study to optimize locoregional treatment with a hyperfractionated accelerated radiotherapy schedule alternating with chemotherapy. From May 1991 to May 1995, 54 patients, previously untreated, with non-metastatic inflammatory breast cancer were entered in an alternating protocol consisting of eight courses of combined chemotherapy and two series of loco-regional hyperfractionated accelerated radiotherapy with a total dose of 66 Gy. Hyperfractionated accelerated radiotherapy was started after three courses of neo-adjuvant chemotherapy (Adriamycin, Vincristine, Cyclophosphamide, Methotrexate, 5-fluoro-uracil) administered every 21 days {+-}G.CSF. The first series delivered 45 Gy/three weeks to the breast, the axillary, sub-clavicular and internal mammary nodes, with two daily sessions of 1.5 Gy separated by an interval of eight hours, the second series consisted of a boost (21 Gy/14 fractions/10d) alternating with another regimen of anthracycline-based-chemotherapy (a total of five cycles every three weeks). Hormonal treatment was given to all patients. Of the 53 patients evaluated at the end of the treatment, 44(83%) had a complete clinical response, seven (13%) had a partial response (>50%) and two (4%) had tumoral progression. Of the 51 patients who were locally controlled, 18 (35%) presented a locoregional recurrence (LRR); eight(15 %) had to undergo a mastectomy. All the patients but two LRR developed metastases or died of local progressive disease and 26 (50%) developed metastases. With a median follow-up of 39 months (range: 4-74 months), survival rates at three and five years were respectively, 66 and 45% for overall survival and 45 and 36% for disease-free survival. Alternating a combination of chemotherapy and hyperfractionated accelerated radiotherapy is a well-tolerated regimen which provides acceptable local control

  5. Can pure accelerated radiotherapy given as six fractions weekly be an option in locally advanced carcinoma cervix: Results of a prospective randomized phase III trial

    Mukesh Sharma

    2016-01-01

    Conclusions: Accelerated radiotherapy given as six fractions per week is an effective alternative to concomitant chemoradiation in locally advanced carcinoma cervix and has shown lesser toxicities in our study.

  6. Late course accelerated hyperfractionation radiotherapy for elderly patients with esophageal carcinoma

    Objective: To study the clinical results and prognostic factors of late course accelerated hyperfractionation radiotherapy (LCAHR) in the treatment of esophageal carcinoma in the elderly. Methods: 105 over 60 year-old patients with esophageal carcinoma who received radical LCAHR, were retrospectively analysed. Radical tumoricidal dose of 67.9-72.0 Gy was delivered in 39-43 fractions over 42-53 days. Results: The 5-year local control rate was 63.7%. The 5-year disease-free survival and overall survival rate were 22.6% and 34.4%. Acute esophagitis and bronchitis were the most common but acceptable radioreactions Grade 1-2. No significant differences were found either in the clinical response or complication, between the 60-69 year and 70-80 year groups. By multivariate analysis, T stage and KPS score were two independent prognostic factors. Of 67 death cases, 31 died of local relapse, 23 of distant metastases, 8 of both and 5 of other causes. Conclusions: LCAHR toxicity, being tolerable for the older esophageal carcinoma patients, may improve their survival and quality of life

  7. Determining optimization of the initial parameters in Monte Carlo simulation for linear accelerator radiotherapy

    Chang, Kwo-Ping; Wang, Zhi-Wei; Shiau, An-Cheng

    2014-02-01

    Monte Carlo (MC) method is a well known calculation algorithm which can accurately assess the dose distribution for radiotherapy. The present study investigated all the possible regions of the depth-dose or lateral profiles which may affect the fitting of the initial parameters (mean energy and the radial intensity (full width at half maximum, FWHM) of the incident electron). EGSnrc-based BEAMnrc codes were used to generate the phase space files (SSD=100 cm, FS=40×40 cm2) for the linac (linear accelerator, Varian 21EX, 6 MV photon mode) and EGSnrc-based DOSXYZnrc code was used to calculate the dose in the region of interest. Interpolation of depth dose curves of pre-set energies was proposed as a preliminary step for optimal energy fit. A good approach for determination of the optimal mean energy is the difference comparison of the PDD curves excluding buildup region, and using D(10) as a normalization method. For FWHM fitting, due to electron disequilibrium and the larger statistical uncertainty, using horn or/and penumbra regions will give inconsistent outcomes at various depths. Difference comparisons should be performed in the flat regions of the off-axis dose profiles at various depths to optimize the FWHM parameter.

  8. Retrospective study on therapy options of brain metastases surgery versus stereotactic radiotherapy with the linear accelerator

    Fortunati, M K S

    2001-01-01

    Background: in the therapy of brain metastases there has been a great progress in the last years. It was shown, that more aggressive therapies can not only extend the survival of the patients, but also improve quality of life. The major question of this study was, whether surgery or stereotactic radiotherapy with the linear accelerator show better results in behalf of the survival. Beside this major question many parameters regarding the patient or his primary cancer were examined. Methods: from the 1st of January 1995 until the 30th of June 2000 233 patients with one or more brain metastases have been treated in the Wagner Jauregg Landesnervenkrankenhaus Oberoesterreich (WJ LNKH OeO). The LINAC has been established on the 1st of July 1997. The patients have been distributed in three groups: 1. LINAC-group: 81 patients have been treated from the 1st of July 1997 until the 30th of June 2000 with the LINAC. 2. Surgery-group: 81 patients have been operated from the 1st of July 1997 until the 30th June 2000. 3 Co...

  9. Radiobiological characterization of different energy-photon beams used in radiotherapy from linear accelerator

    The main objective of this study was to perform a radiobiological characterization of different energy photon beams (6 MV and 15 MV) from linear accelerator used in radiotherapy, and comparison of different treatment modalities, with special regard to late effects of radiation. Using two end points, cell survival and micronucleus induction, in the biological system (Chines hamster V79 cell line). Chromosomes number was counted and found to be 22 chromosomes per cell. Cells were kept in confluent growth for two days and then exposed to two photon beams and immediately after irradiation were counted and re seeded in different numbered for each dose. For evaluation of surviving fraction samples were incubated at 37oC for 6 days, five samples were counted for each dose. At the same time three samples were seeded for the micronuclei frequency and incubated at 37oC after 24 hours cytochalasin-B was added to block cells in cytokinesis. The survival curve showed similar curves for the two beams and decreased with dose. The micronuclei frequency was positively correlated with dose and the energy of the photon. This indicates the presence of low dose of photoneutrons produced by using high energy photon beams. (Author)

  10. Hypofractionated and Accelerated Radiotherapy With Subcutaneous Amifostine Cytoprotection as Short Adjuvant Regimen After Breast-Conserving Surgery: Interim Report

    Purpose: Short radiotherapy schedules might be more convenient for patients and overloaded radiotherapy departments, provided late toxicity is not increased. We evaluated the efficacy and toxicity of a hypofractionated and highly accelerated radiotherapy regimen supported with cytoprotection provided by amifostine in breast cancer patients treated with breast-conserving surgery. Methods and Materials: A total of 92 patients received 12 consecutive fractions of radiotherapy (3.5 Gy/fraction for 10 fractions) to the breast and/or axillary/supraclavicular area and 4 Gy/fraction for 2 fractions to the tumor bed). Amifostine at a dose of 1,000 mg/d was administered subcutaneously. The follow-up of patients was 30-60 months (median, 39). Results: Using a dose individualization algorithm, 77.1% of patients received 1,000 mg and 16.3% received 750 mg of amifostine daily. Of the 92 patients, 13% interrupted amifostine because of fever/rash symptoms. Acute Grade 2 breast toxicity developed in 6.5% of patients receiving 1,000 mg of amifostine compared with 46.6% of the rest of the patients (p < .0001). The incidence of Grade 2 late sequelae was less frequent in the high amifostine dose group (3.2% vs. 6.6%; p = NS). Grade 1 lung fibrosis was infrequent (3.3%). The in-field relapse rate was 3.3%, and an additional 2.2% of patients developed a relapse in the nonirradiated supraclavicular area. c-erbB-2 overexpression was linked to local control failure (p = .01). Distant metastasis appeared in 13% of patients, and this was marginally related to more advanced T/N stage (p = .06). Conclusion: Within a minimal follow-up of 2.5 years after therapy, hypofractionated and accelerated radiotherapy with subcutaneous amifostine cytoprotection has proved a well-tolerated and effective regimen. Longer follow-up is required to assess the long-term late sequelae.

  11. Avoidance of treatment interruption: an unrecognized benefit of accelerated radiotherapy in oropharyngeal carcinomas?

    Purpose: To assess the impact of treatment interruption on the potential gain in locoregional control obtained with accelerated radiotherapy (RT) compared with conventionally fractionated RT in patients with oropharyngeal carcinomas. Methods and Materials: 152 patients treated with radical RT for oropharyngeal carcinomas between 1979 and 1996 were retrospectively analyzed. According to the American Joint Committee on Cancer (AJCC) staging system, there were 6/30/43/73 stages I/II/III/IV. Sixty-one patients were treated with a conventional RT schedule (median dose 70 Gy in 35 fractions), and 91 patients with either of two 5/5.5-week accelerated RT schedules (median dose 69.6-69.9 Gy in 41 fractions). Discounting weekends, RT was interrupted for 2 consecutive days or more in 53 patients (median duration 11 days, range 2-97), including 67% of the patients in the conventional RT group and 13% in the accelerated RT group. Median follow-up for surviving patients was 55 months (range 23-230). The Cox proportional hazards model was used for the multivariate analysis of factors influencing locoregional control. Results: In univariate analysis, factors associated with a significant decrease in locoregional control included WHO performance status ≥1, advanced AJCC stages (III and IV), conventional RT fractionation, overall treatment time ≥44 days (median), and RT interruption. In the multivariate analysis, when introduced into the model individually, the three significant therapeutic factors remained significant after adjustment for the forced clinical variables. However, when the three therapeutic factors were introduced together into the model, beside the AJCC stage (P = 0.017), only RT interruption remained a significant independent adverse prognostic factor (P = 0.026). Conclusions: This multivariate analysis highlights the potential negative impact of treatment gaps on locoregional control in oropharyngeal carcinomas. This suggests that treatment interruption may be

  12. Short-Course Accelerated Radiotherapy in Palliative Treatment of Advanced Pelvic Malignancies: A Phase I Study

    Caravatta, Luciana [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Padula, Gilbert D.A. [Department of Radiation Oncology, Lacks Cancer Center Saint Mary' s Health Care, Grand Rapids, MI (United States); Macchia, Gabriella, E-mail: gmacchia@rm.unicatt.it [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Ferrandina, Gabriella [Department of Gynecologic Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Bonomo, Pierluigi; Deodato, Francesco; Massaccesi, Mariangela [Department of Radiation Oncology, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Mignogna, Samantha; Tambaro, Rosa [Department of Palliative Therapies, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Rossi, Marco [Department of Anaesthesia, Intensive Care, and Pain Medicine, Fondazione di Ricercae Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Flocco, Mariano [' Madre Teresa di Calcutta' Hospice, Larino (Italy); Scapati, Andrea [Department of Radiation Oncology, ' San Francesco' Hospital, Nuoro (Italy); and others

    2012-08-01

    Purpose: To define the maximum tolerated dose of a conformal short-course accelerated radiotherapy in patients with symptomatic advanced pelvic cancer. Methods and Materials: A phase I trial in 3 dose-escalation steps was designed: 14 Gy (3.5-Gy fractions), 16 Gy (4-Gy fractions), and 18 Gy (4.5-Gy fractions). The eligibility criteria included locally advanced and/or metastatic pelvic cancer and Eastern Cooperative Oncology Group performance status of {<=}3. Treatment was delivered in 2 days with twice-daily fractionation and at least an 8-hour interval. Patients were treated in cohorts of 6-12 to define the maximum tolerated dose. The dose-limiting toxicity was defined as any acute toxicity of grade 3 or greater, using the Radiation Therapy Oncology Group scale. Pain was recorded using a visual analog scale. The effect on quality of life was evaluated according to Cancer Linear Analog Scale (CLAS). Results: Of the 27 enrolled patients, 11 were male and 16 were female, with a median age of 72 years (range 47-86). The primary tumor sites were gynecologic (48%), colorectal (33.5%), and genitourinary (18.5%). The most frequent baseline symptoms were bleeding (48%) and pain (33%). Only grade 1-2 acute toxicities were recorded. No patients experienced dose-limiting toxicity. With a median follow-up time of 6 months (range 3-28), no late toxicities were observed. The overall (complete plus partial) symptom remission was 88.9% (95% confidence interval 66.0%-97.8%). Five patients (41.7%) had complete pain relief, and six (50%) showed >30% visual analog scale reduction. The overall response rate for pain was 91.67% (95% confidence interval 52.4%-99.9%). Conclusions: Conformal short course radiotherapy in twice-daily fractions for 2 consecutive days was well tolerated up to a total dose of 18 Gy. A phase II study is ongoing to confirm the efficacy on symptom control and quality of life indexes.

  13. Short-Course Accelerated Radiotherapy in Palliative Treatment of Advanced Pelvic Malignancies: A Phase I Study

    Purpose: To define the maximum tolerated dose of a conformal short-course accelerated radiotherapy in patients with symptomatic advanced pelvic cancer. Methods and Materials: A phase I trial in 3 dose-escalation steps was designed: 14 Gy (3.5-Gy fractions), 16 Gy (4-Gy fractions), and 18 Gy (4.5-Gy fractions). The eligibility criteria included locally advanced and/or metastatic pelvic cancer and Eastern Cooperative Oncology Group performance status of ≤3. Treatment was delivered in 2 days with twice-daily fractionation and at least an 8-hour interval. Patients were treated in cohorts of 6-12 to define the maximum tolerated dose. The dose-limiting toxicity was defined as any acute toxicity of grade 3 or greater, using the Radiation Therapy Oncology Group scale. Pain was recorded using a visual analog scale. The effect on quality of life was evaluated according to Cancer Linear Analog Scale (CLAS). Results: Of the 27 enrolled patients, 11 were male and 16 were female, with a median age of 72 years (range 47-86). The primary tumor sites were gynecologic (48%), colorectal (33.5%), and genitourinary (18.5%). The most frequent baseline symptoms were bleeding (48%) and pain (33%). Only grade 1-2 acute toxicities were recorded. No patients experienced dose-limiting toxicity. With a median follow-up time of 6 months (range 3-28), no late toxicities were observed. The overall (complete plus partial) symptom remission was 88.9% (95% confidence interval 66.0%-97.8%). Five patients (41.7%) had complete pain relief, and six (50%) showed >30% visual analog scale reduction. The overall response rate for pain was 91.67% (95% confidence interval 52.4%-99.9%). Conclusions: Conformal short course radiotherapy in twice-daily fractions for 2 consecutive days was well tolerated up to a total dose of 18 Gy. A phase II study is ongoing to confirm the efficacy on symptom control and quality of life indexes.

  14. Retrospective study on therapy options of brain metastases: surgery versus stereotactic radiotherapy with the linear accelerator

    Background: in the therapy of brain metastases there has been a great progress in the last years. It was shown, that more aggressive therapies can not only extend the survival of the patients, but also improve quality of life. The major question of this study was, whether surgery or stereotactic radiotherapy with the linear accelerator show better results in behalf of the survival. Beside this major question many parameters regarding the patient or his primary cancer were examined. Methods: from the 1st of January 1995 until the 30th of June 2000 233 patients with one or more brain metastases have been treated in the Wagner Jauregg Landesnervenkrankenhaus Oberoesterreich (WJ LNKH OeO). The LINAC has been established on the 1st of July 1997. The patients have been distributed in three groups: 1. LINAC-group: 81 patients have been treated from the 1st of July 1997 until the 30th of June 2000 with the LINAC. 2. Surgery-group: 81 patients have been operated from the 1st of July 1997 until the 30th June 2000. 3 Control-group: 71 patients have been operated from the 1st of January 1995 until the 30th of June 1997, before the LINAC has been established on the 1st of July 1997. Results: There are shown the mean survival times. Therapy options (0,05): LINAC-group: 377 days. Surgery-group: 195 days. Control-group: 285 days. Primary cancer (0,05): unknown primary: 203 days. Cancer of the colon tract: 218 days. Breast cancer: 314 days. Melanoma: 162 days. Kidney: 466 days. Lung 261 days. Others: 439 days. Metastases in one/in both hemispheres (0,05): in one hemisphere 310 days, in both 184 days. All the other parameters (age, sex, Karnofsky-Index, period between diagnose of the primary and the brain metastases, primary cancer therapy, extra cerebral metastases, number of metastases, localization of metastases supra- or infratentoriell, dose/effect relationship in the LINAC-group, whole brain radiotherapy) showed interesting differences, but the results were not statistically

  15. Development and Dosimetric Characterization of a Tissue Substitute (Bolus) For Use in Linear Accelerator Electron Radiotherapy

    We propose the design of a new custom made material, to be used as a tissue substitute in external beam electron radiotherapy, based on cotton fabric and beeswax. Due to its inexpensive, easy preparation, constant thickness, flexibility, uniform density and physical properties similar to those of soft tissue, this bolus will insure personalized optimal dose build up and dose distribution in irregular treatment regions. Materials and Methods: We used commercial Campeche beeswax and 100% cotton fabric to prepare the bolus. Beeswax's physical characteristics were determined by thermal and density analysis. Its chemical properties are to be determined by electronic microscopy. We performed quality control tests and calibration of the Varian 2100C linear accelerator. The tissue equivalence of the material is established for a range of electron energies (6, 9, 12, 16, 20 MeV) using a water equivalent solid phantom (PTW; Freiburg, Germany) and a plane parallel ionization chamber (PTW) associated to a PTW electrometer. Results: Beeswax's absolute density was found to be 0.9181g/ml at 21 deg. C, with a melting point of 45 deg. C. For the bolus elaboration, the cotton fabric was soaked in liquid beeswax and thin sheets of approximately 1 mm were obtained. These presented high flexibility, physical stability (color, texture, thickness) and homogeneity. Determination of this dosimetric characteristics and equivalent thickness are still in process. Discussion and conclusions: Our preliminary results suggest that the tissue substitute is easily made, inexpensive to produce, molds well to the treatment area and its positioning is easy and reproducible over the course of the treatment. So we consider that it's a good alternative to the commercial bolus

  16. Output trends, characteristics, and measurements of three megavoltage radiotherapy linear accelerators.

    Hossain, Murshed

    2014-01-01

    The purpose of this study is to characterize and understand the long-term behavior of the output from megavoltage radiotherapy linear accelerators. Output trends of nine beams from three linear accelerators over a period of more than three years are reported and analyzed. Output, taken during daily warm-up, forms the basis of this study. The output is measured using devices having ion chambers. These are not calibrated by accredited dosimetry laboratory, but are baseline-compared against monthly output which is measured using calibrated ion chambers. We consider the output from the daily check devices as it is, and sometimes normalized it by the actual output measured during the monthly calibration of the linacs. The data show noisy quasi-periodic behavior. The output variation, if normalized by monthly measured "real' output, is bounded between ± 3%. Beams of different energies from the same linac are correlated with a correlation coefficient as high as 0.97, for one particular linac, and as low as 0.44 for another. These maximum and minimum correlations drop to 0.78 and 0.25 when daily output is normalized by the monthly measurements. These results suggest that the origin of these correlations is both the linacs and the daily output check devices. Beams from different linacs, independent of their energies, have lower correlation coefficient, with a maximum of about 0.50 and a minimum of almost zero. The maximum correlation drops to almost zero if the output is normalized by the monthly measured output. Some scatter plots of pairs of beam output from the same linac show band-like structures. These structures are blurred when the output is normalized by the monthly calibrated output. Fourier decomposition of the quasi-periodic output is consistent with a 1/f power law. The output variation appears to come from a distorted normal distribution with a mean of slightly greater than unity. The quasi-periodic behavior is manifested in the seasonally averaged output

  17. Nelson's syndrome: single centre experience using the linear accelerator (LINAC) for stereotactic radiosurgery and fractionated stereotactic radiotherapy.

    Wilson, Peter J; Williams, Janet R; Smee, Robert I

    2014-09-01

    Nelson's syndrome is a unique clinical phenomenon of growth of a pituitary adenoma following bilateral adrenalectomies for the control of Cushing's disease. Primary management is surgical, with limited effective medical therapies available. We report our own institution's series of this pathology managed with radiation: prior to 1990, 12 patients were managed with conventional radiotherapy, and between 1990 and 2007, five patients underwent stereotactic radiosurgery (SRS) and two patients fractionated stereotactic radiotherapy (FSRT), both using the linear accelerator (LINAC). Tumour control was equivocal, with two of the five SRS patients having a reduction in tumour volume, one patient remaining unchanged, and two patients having an increase in volume. In the FSRT group, one patient had a decrease in tumour volume whilst the other had an increase in volume. Treatment related morbidity was low. Nelson's syndrome is a challenging clinical scenario, with a highly variable response to radiation in our series. PMID:24825407

  18. Radiosensitivity of mouse lip mucosa: Influence of anesthesia, carbogen, and a new high O2 carrying perfluorochemical emulsion

    The effect of a new perfluorochemical emulsion based on F-66E (54%, w/v) which carries, in combination with carbogen, twice as much oxygen as Fluosol-DA 20% was tested on the radiation response of the lip mucosa of unanesthetized mice. Mice were pretreated with 0.015 ml/g of the F-66E emulsion in the presence of carbogen for 1 h prior to and during irradiation. There was a significant increase in the mortality rate following the highest radiation dose in mice given F-66E emulsion plus carbogen. The reactions of lip mucosa of mice given F-66E emulsion and/or carbogen were not significantly different from that of the control group using three end points (average score, mean peak, incidence of mucosal desquamation), but the peak mucosal reaction was delayed. The radiosensitivity of the mouse lip mucosa to Ethrane, an anesthetic gas inhaled with carbogen, was also tested. The reaction of lip mucosa in the anesthetized mice was significantly greater than that of the control group. There was also a significant increase in the mortality rate following the two highest radiation doses

  19. Prospective, longitudinal electroglottographic study of voice recovery following accelerated hypofractionated radiotherapy for T1/T2 larynx cancer

    Background and purpose: To measure voice outcomes following accelerated hypofractionated radiotherapy for larynx cancer. Materials and methods: Twenty-five patients with T1/T2 glottic cancer underwent serial electroglottographic and acoustic analysis (sustained vowel/i/ and connected speech) before radiotherapy and 1, 6 and 12 months post-treatment. Twenty-five normal subjects served as a reference control population. Results: Pre-treatment measures were significantly worse for larynx cancer patients. Median jitter (0.23% vs 0.97%, p = 0.001) and shimmer (0.62 dB vs 0.98 dB, p = 0.05) and differences in data ranges reflected greater frequency and amplitude perturbation in the larynx cancer patients. Pre-treatment Mean Phonation Time (MPT) was significantly reduced (21 s vs 14.8 s, p = 0.002) in larynx cancer patients. There was a trend towards improvement of jitter, shimmer and normalized noise energy at 12 months post-treatment. MPT improved but remained significantly worse than for normal subjects (21 s vs 16.4 s, p = 0.013). Average fundamental frequency resembled normal subjects, including improvement of the measured range (91.4-244.6 Hz in controls vs 100-201 Hz in post-treatment larynx cancer patients). Conclusions: This non-invasive technique effectively measures post-treatment vocal function in larynx cancer patients. This study demonstrated improvement of many key parameters that influence voice function over 12 months after radiotherapy

  20. Bevacizumab, Capecitabine, Amifostine, and Preoperative Hypofractionated Accelerated Radiotherapy (HypoArc) for Rectal Cancer: A Phase II Study

    Purpose: Bevacizumab has established therapeutic activity in patients with metastatic colorectal cancer, and anti-vascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models. We assessed the feasibility and efficacy of preoperative radiochemotherapy combined with bevacizumab in patients with rectal cancer. Methods and Materials: Nineteen patients with radiologic T3 and/or N+ rectal carcinoma were treated with preoperative conformal hypofractionated accelerated radiotherapy (3.4 Gy in 10 consecutive fractions) supported with amifostine (500-1,000 mg daily), capecitabine (600 mg/m2 twice daily, 5 days per week), and bevacizumab (5 mg/kg every 2 weeks for 2 cycles). Surgery followed 6 weeks after the end of radiotherapy. A cohort of 14 sequential patients treated with the same regimen without bevacizumab was available for comparison. Results: Grade 2 or 3 diarrhea was noted in 7 of 19 patients (36.8%), which was statistically worse than patients receiving the same regimen without bevacizumab (p = 0.01). A higher incidence of Grade 2 or 3 proctalgia was also noted (21.1%) (p = 0.03). Bladder and skin toxicity was negligible. All toxicities regressed completely within 2 weeks after the end of therapy. Pathologic complete and partial response was noted in 7 of 19 cases (36.8%) and 8 of 19 cases (42.1%). Within a median follow-up of 21 months, none of the patients has had late complications develop and only 1 of 18 evaluable cases (5.5%) has had locoregional relapse. Conclusions: Bevacizumab can be safely combined with hypofractionated radiotherapy and capecitabine as a preoperative radiochemotherapy regimen for patients with rectal cancer. The high pathologic complete response rates urges the testing of bevacizumab in randomized studies.

  1. A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

    Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as

  2. Effect of external shielding for neutrons during radiotherapy for prostate cancer, considering the 2300 CD linear accelerator and voxel phantom

    Thalhofer, J. L.; Roque, H. S.; Rebello, W. F.; Correa, S. A.; Silva, A. X.; Souza, E. M.; Batita, D. V. S.; Sandrini, E. S.

    2014-02-01

    Photoneutron production occurs when high energy photons, greater than 6.7 MeV, interact with linear accelerator head structures. In Brazil, the National Cancer Institute, one of the centers of reference in cancer treatment, uses radiation at 4 angles (0°, 90°, 180° and 270°) as treatment protocol for prostate cancer. With the objective of minimizing the dose deposited in the patient due to photoneutrons, this study simulated radiotherapy treatment using MCNPX, considering the most realistic environment; simulating the radiotherapy room, the Linac 2300 head, the MAX phantom and the treatment protocol with the accelerator operating at 18 MV. In an attempt to reduce the dose deposited by photoneutrons, an external shielding was added to the Linac 2300. Results show that the equivalent dose due to photoneutrons deposited in the patient diminished. The biggest reduction was seen in bone structures, such as the tibia and fibula, and mandible, at approximately 75%. Besides that, organs such as the brain, pancreas, small intestine, lungs and thyroid revealed a reduction of approximately 60%. It can be concluded that the shielding developed by our research group is efficient in neutron shielding, reducing the dose for the patient, and thus, the risk of secondary cancer, and increasing patient survival rates.

  3. Hyperfractionated Accelerated Radiotherapy (HART) with maintenance chemotherapy for metastatic (M1–3) Medulloblastoma – A safety/feasibility study

    Background and purpose: To evaluate feasibility and toxicity of Hyperfractionated Accelerated Radiotherapy (HART) 1.24 Gy b.i.d. followed by chemotherapy for M1–3 Medulloblastoma (MB). The aim of HART was to use hyperfractionation to improve therapeutic ratio combined with acceleration to minimise tumour cell repopulation during radiotherapy (RT). Materials and methods: Between February 2002 and May 2008, 34 eligible patients (22 male, 12 female) aged 3–15 years (median 7) with metastatic MB (M1–9; M2–3, M3–22) received HART with a craniospinal radiotherapy (CSRT) dose of 39.68 Gy followed by 22.32 Gy boost to the whole posterior fossa and 9.92 Gy metastatic boosts. The 8th and subsequent patients received vincristine (VCR) 1.5 mg/m2 weekly × 8 doses over 8 weeks starting during the 1st week of RT. Maintenance chemotherapy comprised 8 six-weekly cycles of VCR 1.5 mg/m2 weekly × 3, CCNU 75 mg/m2 and cisplatin 70 mg/m2. Results: Median duration of HART was 34 days (range 31–38). Grade 3–4 toxicities included mucositis (8), nausea (10), anaemia (5), thrombocytopaenia (2), leucopaenia (24). With 4.5-year median follow-up, 3-year EFS and OS were 59% and 71%, respectively. Of 10 relapses, 1 was outside the central nervous system (CNS), 1 posterior fossa alone and 8 leptomeningeal with 3 also associated with posterior fossa. Conclusion: HART with or without VCR was well tolerated and may have a place in the multi-modality management of high-risk MB

  4. Addition of a hypoxic cell selective cytotoxic agent (mitomycin C or porfiromycin) to Fluosol-DA/carbogen/radiation

    Holden, S.A.; Teicher, B.A. (Dana-Farber Cancer Institute, Boston (USA)); Herman, T.S. (Dana-Farber Cancer Institute, Boston (USA) Joint Center for Radiation Therapy, Boston (USA))

    1990-05-01

    In an effort to develop effictive combination treatments for use with radiation against solid tumors, the cytotoxic effects of the addition of mitomycin C or porfiromycin on treatment with Fluosol-DA/carbogen breathing and radiation in the FSaIIC tumor system were studied. In vitro mitomycin C and porfiromycin were both preferentially cytotoxic toward hypoxic FSaIIC cells. After in vivo exposure, however, the cytotoxicity of mitomycin C toward single cell tumor suspensions obtained from whole tumors was exponential over the dose range studied, but for porfiromycin a plateau in cell killing was observed. With Fluosol-DA/carbogen breathing and single dose radiaiton, addition of either mitomycin C or porfiromycin increased the tumor cell kill achieved at 5 Gy by approximately 1.2 and 1.0 logs, respectively. Less effect was seen with addition of the drugs at the 10 and 15 Gy radiation doses. In tumor growth delay experiments, the addition of either mitomycin C or porfiromycin to Fluosol-DA/carbogen breathing and radiation resulted in primarily an additive increase in tumor growth delay. The survival of Hoechst 33342 dye-selected tumor cell subpopulations indicated that Fluosol-DA/carbogen breathing increased the cytotoxicity of radiation (10 Gy) more in the bright cell subpopulation (4-fold) than in the dim cell subpopulation (2-fold) resulting in an overall 4-fold sparing of the dim subpopulation. Mitomycin C and porfiromycin were both more toxic toward the dim cell subpopulations. Addition of mitomycin C or porfiromycin to Fluosol-DA/carbogen breathing and radiation (10 Gy) resulted in a primarily additive effect of the drugs and radiation killing in both tumor cell subpopulations. Thus, with mitomycin C/Fluosol-DA/carbogen and radiation there was a 2-fold sparing of dim cells and with profiromycin in the combined treatment a 1.6-fold sparing of the dim cell population. (Abstract Truncated)

  5. Perfusion changes in the RIF-1 tumour and normal tissues after carbogen and nicotinamide, individually and combined.

    Honess, D. J.; Bleehen, N.M.

    1995-01-01

    The strategy of combining carbogen breathing and nicotinamide to overcome chronic and acute hypoxia respectively is being evaluated clinically. The effects of both agents individually and in combination on relative perfusion of 400-700 mm3 RIF-1 tumours and normal tissues were measured by 86Rb extraction. Carbogen breathing alone for 6 min increased relative tumour perfusion by 50-70% compared with control at flow rates of 50 to 200 ml min-1, but the effect was lost at 300 ml min-1. All flow ...

  6. Evolution of Hypofractionated Accelerated Radiotherapy for Prostate Cancer – The Sunnybrook Experience

    Hima Bindu Musunuru

    2014-11-01

    Full Text Available Stereotactic Ablative Body Radiotherapy (SABR is a newer method of ultra hypo fractionated radiotherapy that uses combination of image guided radiotherapy (IGRT and intensity modulated radiotherapy(IMRT or volumetric modulated arc therapy(VMAT, to deliver high doses of radiation in a few fractions to a target, at the same time sparing the surrounding organs at risk(OAR.SABR is ideal for treating small volumes of disease and has been introduced in a number of disease sites including brain, lung, liver, spine and prostate. Given the radiobiological advantages of treating prostate cancer with high doses per fraction, SABR is becoming a standard of care for low and intermediate risk prostate cancer patients based upon the results from Sunny Brook and also the US-based prostate SABR consortium. This review examines the development of moderate and ultra hypo fractionation schedules at the Odette Cancer centre, Sunnybrook Health Sciences. Moderate hypo fractionation protocol was first developed in 2001 for intermediate risk prostate cancer and from there on different treatment schedules including SABR evolved for all risk groups.

  7. Prospective randomized trial to compare accelerated (six fractions a week radiotherapy against concurrent chemoradiotherapy (using conventional fractionation in locally advanced head and neck cancers

    Manoj Gupta

    2015-01-01

    Full Text Available Background: Concurrent chemoradiation (CCRT is currently considered to be the standard of care in locally advanced head and neck cancer. The optimum radiotherapy schedule for best local control and acceptable toxicity is not yet clear. We aimed at shortening of treatment time by using accelerated radiation, thereby comparing the disease response, loco-regional tumor control and tolerability of accelerated radiation (six fractions per week against CCRT in locally advanced head and neck cancer. Materials and Methods: We conducted the prospective randomized study for a period of 2 years from June 2011 to May 2013 in 133 untreated patients of histologically confirmed squamous cell carcinoma of head and neck. Study group (66 patients received accelerated radiotherapy with 6 fractions per week (66Gy/33#/5½ weeks. Control group (67 patients received CCRT with 5 fractions per week radiation (66 Gy/33#/6½ weeks along with intravenous cisplatin 30 mg/m 2 weekly. Tumor control, survival, acute and late toxicities were assessed. Results: Median overall treatment time was 38 days and 45 days in the accelerated radiotherapy and concurrent chemoradiation arm, respectively. At a median follow up of 12 months, 41 patients (62.1% in the accelerated radiotherapy arm and 47 patients (70.1% in the CCRT arm were disease free (P = 0.402. Local disease control was comparable in both the arms. Acute toxicities were significantly higher in the CCRT arm as compared with accelerated radiotherapy arm. There was no difference in late toxicities between the two arms. Conclusion: We can achieve, same or near to the same local control, with lower toxicities with accelerated six fractions per week radiation compared with CCRT especially for Indian population.

  8. Effectiveness of surgery and individualized high-dose hyperfractionated accelerated radiotherapy on survival in clinical stage I non-small cell lung cancer. A propensity score matched analysis

    Background and purpose: Surgery is considered the treatment of choice for early-stage non-small cell lung cancer (NSCLC). Patients with poor pulmonary function or other comorbidities are treated with radiotherapy. The objective of this investigation is to compare the 3-year survival of two early-stage NSCLC populations treated in two different hospitals, either by surgical resection (lobectomy) or by individualized high-dose accelerated radiotherapy, after matching patients by propensity scoring analysis. Methods: A retrospective comparative study has been performed on two series of consecutive patients with cytohistological diagnosis of NSCLC, clinically staged IA by means of PET-scan (radiotherapy group) and pathologically staged IA (surgery group). Results: A total of 157 cases were initially selected for the analysis (110 operated and 47 treated by radiotherapy). Patients in the radiotherapy group were older, with higher comorbidity and lower FEV1% with 3-years probability of survival for operated patients higher than that found for patients treated by radiotherapy. After matching by propensity scoring (using age and FEV1%), differences disappear and 3-years probability of survival had no statistical differences. Conclusions: Although this is a non-randomized retrospective analysis, we have not found 3-years survival differences after matching cases between surgery and radiotherapy. Nevertheless, data presented here support the continuous investigation for non-surgical alternatives in this disease.

  9. The Nano-X Linear Accelerator: A Compact and Economical Cancer Radiotherapy System Incorporating Patient Rotation.

    Eslick, Enid M; Keall, Paul J

    2015-10-01

    Rapid technological improvements in radiotherapy delivery results in improved outcomes to patients, yet current commercial systems with these technologies on board are costly. The aim of this study was to develop a state-of-the-art cancer radiotherapy system that is economical and space efficient fitting with current world demands. The Nano-X system is a compact design that is light weight combining a patient rotation system with a vertical 6 MV fixed beam. In this paper, we present the Nano-X system design configuration, an estimate of the system dimensions and its potential impact on shielding cost reductions. We provide an assessment of implementing such a radiotherapy system clinically, its advantages and disadvantages compared to a compact conventional gantry rotating linac. The Nano-X system has several differentiating features from current radiotherapy systems, it is [1] compact and therefore can fit into small vaults, [2] light weight, and [3] engineering efficient, i.e., it rotates a relatively light component and the main treatment delivery components are not under rotation (e.g., DMLCs). All these features can have an impact on reducing the costs of the system. In terms of shielding requirements, leakage radiation was found to be the dominant contributor to the Nano-X vault and as such no primary shielding was necessary. For a low leakage design, the Nano-X vault footprint and concrete volume required is 17 m2 and 35 m3 respectively, compared to 54 m2 and 102 m3 for a conventional compact linac vault, resulting in decreased costs in shielding. Key issues to be investigated in future work are the possible patient comfort concerns associated with the patient rotation system, as well as the magnitude of deformation and subsequent adaptation requirements. PMID:24949649

  10. A randomized study of accelerated fractionation radiotherapy with and without mitomycin C in the treatment of locally advanced head and neck cancer

    Ezzat, M.; Shouman, T.; Zaza, K.;

    2005-01-01

    Objectives: This single-institution study evaluates the feasibility of accelerated fractionation radiotherapy (AF) with and without mitomycin C (MMC) in the treatment of locally advanced head and neck cancer. Patients and Methods: Between May 1998 and October 2001, sixty patients with locally...... advanced stage III and IV of head and neck cancer were randomized into three treatment arms: (1) conventional fractionation radiotherapy (CF) (5 fractions per week); (2) accelerated fractionation radiotherapy (AF) (6 fractions per week); and (3) AF plus Mitomycin C (MMC). Results: The 2-year overall...... survival (OS) of the whole group was 21%. The OS according to treatment arm was 23%, 20%, and 28% in CF, AF, and AF+MMC arms respectively (p<0.19). The 2-year loco-regional control (LC) rate was 22% for the whole group of patients. The LC was 10%, 25%, and 30% for the CF, AF, and AF+MMC respectively (p=0...

  11. Prevalence and peak incidence of acute and late normal tissue morbidity in the DAHANCA 6&7 randomised trial with accelerated radiotherapy for head and neck cancer

    Mortensen, Hanna R.; Overgaard, Jens; Specht, Lena;

    2012-01-01

    BACKGROUND AND PURPOSE: The aim of this report was to describe the incidence and prevalence of acute and late morbidity in the DAHANCA 6&7 multicentre randomised trial with accelerated radiotherapy for squamous cell carcinoma of the head and neck. MATERIALS AND METHODS: The DAHANCA 6&7 study...

  12. Dosimetric comparison of the linear accelerators at the University Clinic of Radiotherapy and Oncology in Skopje, Macedonia

    In radiotherapy practice, for various practical reasons it is important to know whether two or more linear accelerators (linacs) are dosimetric matched and whether the patient’s treatment can be shifted from one linac to another without reducing the treatment quality. This work presents the data from the dosimetric comparison of the two Varian Clinacs 23EX and one Varian Clinac iX at the University Clinic of Radiotherapy and Oncology in Skopje. Both Percentage Depth Dose (PDD) and Beam Profile (BP) curves were compared for the photon energies (6MV, 15MV) in use at the clinic. The comparison was performed using the IBA OmniPro Accept 7.4™ software. The results from the comparison of the PDD curves showed that in the clinically significant region the dose differences were smaller than 1%. The results from the comparison of the in line and cross line BP curves showed that in the flattened area the dose differences were smaller than 2.5%, while in the penumbra region they were usually between 2% and 8%, but sometimes up to 21%. This suggests that for treatments where the influence of the penumbra region is small, the three linacs may be considered to be dosimetric matched. For treatments where the influence of the penumbra region is greater, the patient can be switched to another machine only after recalculation of the treatment plan. (Author)

  13. Application Monte Carlo code calculates dose distribution of the emitted photon beams from linear accelerator in case radiotherapy lung cancer

    The dose distribution calculation is one of major steps in cancer radiotherapy. This paper applies Monte Carlo code, MCNP5, in simulation 15 MV photon beams from linear accelerator of General Hospital of Kien Giang in a case treatment of lung cancer. The settings for beam direction, field size and isocenter position used in MCNP5 must be the same as in treatment plan at hospital to ensure the results from MCNP5 are accurate. We also built a program CODIM by using MATLAB® programming software. This program is used to construct digital voxel phantoms from lung CT images obtained from cancer treatment cases at Kien Giang hospital and then simulate the delivered dose of linac in these phantoms by using MCNP5 simulation code. The results show that there is a difference of 5% in comparison to Prowess Panther program - a semi-empirical simulation program which is being used for treatment planning in Kien Giang hospital. (author)

  14. Supratentorial primitive neuroectodermal tumors (S-PNET) in children: A prospective experience with adjuvant intensive chemotherapy and hyperfractionated accelerated radiotherapy

    Purpose: Supratentorial primitive neuroectodermal tumors (S-PNET) are rare and have a grim prognosis, frequently taking an aggressive course with local relapse and metastatic spread. We report the results of a mono-institutional therapeutic trial. Methods and Materials: We enrolled 15 consecutive patients to preradiation chemotherapy (CT) consisting of high-dose methotrexate, high-dose etoposide, high-dose cyclophosphamide, and high-dose carboplatin, craniospinal irradiation (CSI) with hyperfractionated accelerated radiotherapy (HART) plus focal boost, maintenance with vincristine/lomustine or consolidation with high-dose thiotepa followed by autologous stem-cell rescue. Results: Median age was 9 years; 7 were male, 8 female. Site of disease was pineal in 3, elsewhere in 12. Six patients were had no evidence of disease after surgery (NED). Of those with evidence of disease after surgery (ED), 2 had central nervous system spread. Of the 9 ED patients, 2 had complete response (CR) and 2 partial response (PR) after CT, 4 stable disease, and 1 progressive disease. Of the 7 ED patients before radiotherapy, 1 had CR, 4 PR, and 2 minor response, thus obtaining a 44% CR + PR after CT and 71% after HART. Because of rapid progression in 2 of the first 5 patients, high-dose thiotepa was systematically adopted after HART in the subsequent 10 patients. Six of 15 patients relapsed (4 locally, 1 locally with dissemination, 1 with dissemination) a mean of 6 months after starting CT, 2 developed second tumors; 5 of 6 relapsers died at a median of 13 months. Three-year progression-free survival, event-free survival, and overall survival were 54%, 34%, and 61%, respectively. Conclusion: Hyperfractionated accelerated RT was the main tool in obtaining responses in S-PNET; introducing the myeloablative phase improved the prognosis (3/10 vs. 3/5 relapses), though the outcome remained unsatisfactory despite the adoption of this intensive treatment

  15. Locoregionally advanced carcinoma of the oropharynx: conventional radiotherapy vs. accelerated hyperfractionated radiotherapy vs. concomitant radiotherapy and chemotherapy - a multicenter randomized trial

    Purpose: To compare conventional fractionation radiation therapy (RT), Arm A, vs. split-course accelerated hyperfractionated RT (S-AHF), Arm B, vs. conventional fractionation RT plus concomitant chemotherapy (CT), Arm C, in terms of survival and toxicity for advanced, unresectable epidermoid tumors of oropharynx. Methods and Materials: Between January 1993 and June 1998, 192 previously untreated patients affected with Stage III and IV oropharyngeal carcinoma (excluding T1N1 and T2N1) were accrued in a multicenter, randomized Phase III trial (ORO 93-01). For Arms A and C, 66-70 Gy in 33-35 fractions, 5 days a week, were administered in 6.5-7 weeks to tumor and positive nodes. In Arm B, the dose delivered to tumor and involved nodes was 64-67.2 Gy, giving 2 fractions of 1.6 Gy every day with an interfraction interval of at least 4 h and preferably 6 h, 5 days a week. At 38.4 Gy, a 2-week split was planned; after the split, RT was resumed with the same modality. In Arm C, CT regimen consisted of carboplatin and 5-fluorouracil (CBDCA 75 mg/m2, Days 1-4; 5-FU 1,000 mg/m2 i.v. over 96 h, Days 1-4, recycling every 28 days (at 1st, 5th, and 9th week). Results: No statistically significant difference was detected in overall survival (p=0.129): 40% Arm A vs. 37% Arm B vs. 51% Arm C were alive at 24 months. Similarly, there was no statistically significant difference in terms of event-free survival (p=0.196): 20% for Arm A, 19% for Arm B, and 37% for Arm C were event free at 24 months. On the contrary, the 2-year disease-free survival was significantly different among the three arms (p = 0.022), with a superiority for Arm C. At 24 months, the proportion of patients without relapse was 42% for Arm C vs. 23% for Arm A and 20% for Arm B. Patients in Arm A less frequently developed G3+ acute mucositis than their counterparts in Arm B or C (14.7% vs. 40.3% vs. 44%). Regarding the CT-related acute toxicity, apart from 1 case of fatal nephrotoxicity, only hematologic G3+ (Grade 3 or

  16. Stereotactic radiotherapy of intracranial lesions with micro multi leaf collimator mounted on linear accelerator

    Stereotactic radiotherapy (SRT) is an advancement on three-dimensional conformal radiotherapy (3DCRT) which aims not only to conform the therapeutic dose volume to the shape of the tumor, but also ensures low dose to the other normal tissues. As the therapeutic dose volume tightly covers the tumor, small variation between intended plan and executed plan parameters may lead to significant under-dose of tumor or over-dose of normal tissue, which may result in the failure of the treatment. Therefore, SRT should be carried out through a well-laid out systematic procedure in order to achieve its goal. This paper highlights the systematic procedure and comprehensive quality assurance (QA) involved at various steps of intracranial SRT followed in our hospital and our preliminary experience with brain lab stereotactic system. Of the 18 patients treated so far with SRT, we have analyzed the SRT treatment plans for the first 11 brain tumor patients to highlight the volume of tumor covered by the therapeutic dose and integral dose to other normal tissues. The average gross target volume (GTV) and planning target volume (PTV) treated are 14.07 cc, and 43.72 cc, respectively. Out of the 11 patients treated, 100% volume of PTV is covered by 95% isodose volume in 4 patients, 99% of PTV in another 4 patients and 98% of PTV in the remaining 3 patients. But in all the cases, a minimum volume of 96% of the GTV is adequately covered by 100% dose. The conformity index of PTV varies from 1.27 to 1.56, with a mean value of 1.42. As the target volume decreases from 76 cc to 20 cc, the mean dose within the target volume increases from 1.7 Gy to 1.76 Gy. The average volume of normal brain treated with 80%, 50% and 33% dose are 6.53 cc, 73 cc and 298 cc, respectively. Stereotactic radiotherapy with static beams and micro-multileaf collimator (mMLC) shaped fields gives the flexibility to tailor the irregular shaped target volume, thereby ensuring better dose conformity and homogeneous dose

  17. GPU-accelerated automatic identification of robust beam setups for proton and carbon-ion radiotherapy

    We demonstrate acceleration on graphic processing units (GPU) of automatic identification of robust particle therapy beam setups, minimizing negative dosimetric effects of Bragg peak displacement caused by treatment-time patient positioning errors. Our particle therapy research toolkit, RobuR, was extended with OpenCL support and used to implement calculation on GPU of the Port Homogeneity Index, a metric scoring irradiation port robustness through analysis of tissue density patterns prior to dose optimization and computation. Results were benchmarked against an independent native CPU implementation. Numerical results were in agreement between the GPU implementation and native CPU implementation. For 10 skull base cases, the GPU-accelerated implementation was employed to select beam setups for proton and carbon ion treatment plans, which proved to be dosimetrically robust, when recomputed in presence of various simulated positioning errors. From the point of view of performance, average running time on the GPU decreased by at least one order of magnitude compared to the CPU, rendering the GPU-accelerated analysis a feasible step in a clinical treatment planning interactive session. In conclusion, selection of robust particle therapy beam setups can be effectively accelerated on a GPU and become an unintrusive part of the particle therapy treatment planning workflow. Additionally, the speed gain opens new usage scenarios, like interactive analysis manipulation (e.g. constraining of some setup) and re-execution. Finally, through OpenCL portable parallelism, the new implementation is suitable also for CPU-only use, taking advantage of multiple cores, and can potentially exploit types of accelerators other than GPUs.

  18. Addition of a hypoxic cell selective cytotoxic agent (mitomycin C or porfiromycin) to Fluosol-DA/carbogen/radiation.

    Holden, S A; Herman, T S; Teicher, B A

    1990-05-01

    In an effort to develop effective combination treatments for use with radiation against solid tumors, the cytotoxic effects of the addition of mitomycin C or porfiromycin on treatment with Fluosol-DA/carbogen (95% O2/5% CO2) breathing and radiation in the FSaIIC tumor system were studied. In vitro mitomycin C and porfiromycin were both preferentially cytotoxic toward hypoxic FSaIIC cells. After in vivo exposure, however, the cytotoxicity of mitomycin C toward single cell tumor suspensions obtained from whole tumors was exponential over the dose range studied, but for porfiromycin a plateau in cell killing was observed. With Fluosol-DA/carbogen breathing and single dose radiation, addition of either mitomycin C or porfiromycin increased the tumor cell kill achieved at 5 Gy by approximately 1.2 and 1.0 logs, respectively. Less effect was seen with addition of the drugs at the 10 and 15 Gy radiation doses. In tumor growth delay experiments, the addition of either mitomycin C or porfiromycin to Fluosol-DA/carbogen breathing and radiation resulted in primarily an additive increase in tumor growth delay. The survival of Hoechst 33342 dye-selected tumor cell subpopulations indicated that Fluosol-DA/carbogen breathing increased the cytotoxicity of radiation (10 Gy) more in the bright cell subpopulation (4-fold) than in the dim cell subpopulation (2-fold) resulting in an overall 4-fold sparing of the dim subpopulation. Mitomycin C and porfiromycin were both more toxic toward the dim cell subpopulations. Addition of mitomycin C or porfiromycin to Fluosol-DA/carbogen breathing and radiation (10 Gy) resulted in a primarily additive effect of the drugs and radiation killing in both tumor cell subpopulations. Thus, with mitomycin C/Fluosol-DA/carbogen and radiation there was a 2-fold sparing of dim cells and with porfiromycin in the combined treatment a 1.6-fold sparing of the dim cell population. Our results indicate that treatment strategies directed against both oxic and

  19. Accelerated partial breast irradiation using 3D conformal radiotherapy: initial clinical experience

    Gatti, M.; Madeddu, A.; Malinverni, G.; Delmastro, E.; Bona, C.; Gabriele, P. [IRCC-Radiotherapy, Candiolo, TO (Italy); Baiotto, B.; Stasi, M. [IRCC-Medical Physics, Candiolo, TO (Italy); Ponzone, R.; Siatis, D. [IRCC-Surgery, Candiolo, TO (Italy)

    2006-11-15

    Accelerated partial breast irradiation using 3D-C.R.T. is technically sophisticate but feasible and acute toxicity to date has been minimal. A C.T.V.-to-P.T.V. margin of 10 mm seems to provide coverage for analyzed patients. However, more patients and additional studies will be needed to validate the accuracy of this margin, and longer follow-up will be needed to assess acute and chronic toxicity, tumor control, and cosmetic results. (author)

  20. Determination of radiation levels by neutrons in an accelerator for radiotherapy

    It was determined the radiation levels by neutrons due to photonuclear reactions (γ, n) which occur in the target, levelling filter, collimators and the small pillow blinding of a medical accelerator Varian Clinac 2100C of 18 MeV, using thermoluminescent dosemeters UD-802AS and US-809AS. The experimental values were presented for the patient level, inside and outside of the radiation field, as well as for the small pillow. (Author)

  1. Fractionated stereotactic radiotherapy with linear accelerator for uveal melanoma - preliminary Vienna results

    Between June 1997 and February 1998, 21 patients suffering from uveal melanomas have been treated with a sterotactic 6 MeV LINAC (Saturne 43 trademark, General Electric, France) in conjunction with a stereotactic frame system (BrainLAB trademark, Germany). Immobilization of the eye was ensured with an optical fixation system which was proven reliable. During radiotherapy, movements of the irradiated eye were controlled on a monitor and documented by video recording. All patients co-operated very well with the optical fixation system. In 1164 measurements, the median value of horizontal deviation of the diseased eye during treatment was 0.3 mm (range: 0 to 1.3 mm). Median vertical deviation was 0.2 mm (range: 0 to 1.2 mm). For all patients, mean tumor prominence before treatment was 6.0±2.2 mm. In 20 patients, the total dose of 70 Gy (at 80%) was delivered in 5 fractions within 10 days. In one patient with a ciliary body tumor, the total dose of 70 Gy was divided into 7 fractions for better sparing of the anterior eye segment. Results: After a follow-up of at least 6 months, local tumor control was seen in all eyes. Mean tumor thickness reduction after 3, 6 and 9 months was 7%, 13% and 31%, respectively. Up to now, only mild subacute side-effects located in the anterior eye segment have been noticed. (orig.)

  2. Accelerated split-course radiotherapy and concomitant cis-platinum and 5-fluorouracil chemotherapy with folinic acid enhancement in unresectable head and neck cancer

    In patients suffering from locally advanced, unresectable squamous cell carcinoma (SCC) of the base of the tongue, the floor of the mouth, the mobile part of the tongue, the tonsils, the hypopharynx and the larynx radiotherapy yields poor results, due to local failure rather than to distant metastases. Since toxicity of radiotherapy and cytotoxic chemotherapy do not overlap entirely efforts were made to achieve better results combining these two treatment modalities. Clinical trials on simultaneous radiotherapy/chemotherapy focussed on two cytotoxic agents: Cis-dichlorodiammineplatinum(II) (cis-DDP) and 5-flourouracil (5-FU). Another approach to overcome the radioresistance of large SCC adopts accelerated fractionation. The potential tumor doubling time of sqamous cell carcinomas is about four days, and thus repopulation of surviving clonogenic tumor cells during fractionated radiotherapy may be the cause of poor treatment results. In this pilot study a twice daily fractionated split-course radiotherapy is combined with simultaneous administration of cis-DDP and 5-FU with folinic acid (FA) enhancement. (orig.)

  3. Accelerated split-course radiotherapy and concomitant cis-platinum and 5-fluorouracil chemotherapy with folinic acid enhancement in unresectable head and neck cancer

    Wendt, T.G.; Wustrow, T.P.U.; Hartenstein, R.C.; Trott, K.R.

    1988-01-01

    In patients suffering from locally advanced, unresectable squamous cell carcinoma (SCC) of the base of the tongue, the floor of the mouth, the mobile part of the tongue, the tonsils, the hypopharynx and the larynx radiotherapy yields poor results, due to local failure rather than to distant metastases. Since toxicity of radiotherapy and cytotoxic chemotherapy do not overlap entirely efforts were made to achieve better results combining these two treatment modalities. Clinical trials on simultaneous radiotherapy/chemotherapy focussed on two cytotoxic agents: Cis-dichlorodiammineplatinum(II) (cis-DDP) and 5-flourouracil (5-FU). Another approach to overcome the radioresistance of large SCC adopts accelerated fractionation. The potential tumor doubling time of sqamous cell carcinomas is about four days, and thus repopulation of surviving clonogenic tumor cells during fractionated radiotherapy may be the cause of poor treatment results. In this pilot study a twice daily fractionated split-course radiotherapy is combined with simultaneous administration of cis-DDP and 5-FU with folinic acid (FA) enhancement.

  4. Can concomitant-boost accelerated radiotherapy be adopted as routine treatment for head-and-neck cancers? A 10-year single-institution experience

    Allal, Abdelkarim Said; Taussky, Daniel; Mach, Nicolas; Becker, Minerva; Bieri, Sabine; Dulguerov, Pavel

    2004-01-01

    Accelerated schedules are effective in overcoming repopulation during radiotherapy (RT) for head-and-neck cancers, but their feasibility is compromised by increased toxicity. The therapeutic ratio may be particularly favorable for 5-week regimens. This study reports the 10-year experience of a single institution in the routine use of concomitant boost RT as standard radical treatment in all but the most favorable stage patients.

  5. Impact of Schedule Duration on Head and Neck Radiotherapy: Accelerated Tumor Repopulation Versus Compensatory Mucosal Proliferation

    Purpose: To determine how modelled maximum tumor control rates, achievable without exceeding mucositis tolerance (tcpmax-early) vary with schedule duration for head and neck squamous cell carcinoma (HNSCC). Methods and materials: Using maximum-likelihood techniques, we have fitted a range of tcp models to two HNSCC datasets (Withers’ and British Institute of Radiology [BIR]), characterizing the dependence of tcp on duration and equivalent dose in 2 Gy fractions (EQD2). Models likely to best describe future data have been selected using the Akaike information criterion (AIC) and its quasi-AIC extension to overdispersed data. Setting EQD2s in the selected tcp models to levels just tolerable for mucositis, we have plotted tcpmax-early against schedule duration. Results: While BIR dataset tcp fits describe dose levels isoeffective for tumor control as rising significantly with schedule protraction, indicative of accelerated tumor repopulation, repopulation terms in fits to Withers’ dataset do not reach significance after accounting for overdispersion of the data. The tcpmax-early curves calculated from tcp fits to the overall Withers’ and BIR datasets rise by 8% and 0-4%, respectively, between 20 and 50 days duration; likewise, tcpmax-early curves calculated for stage-specific cohorts also generally rise slowly with increasing duration. However none of the increases in tcpmax-early calculated from the overall or stage-specific fits reach significance. Conclusions: Local control rates modeled for treatments which lie just within mucosal tolerance rise slowly but insignificantly with increasing schedule length. This finding suggests that whereas useful gains may be made by accelerating unnecessarily slow schedules until they approach early reaction tolerance, little is achieved by shortening schedules further while reducing doses to remain within mucosal tolerance, an approach that may slightly worsen outcomes.

  6. The role of accelerated hyperfractionated radiotherapy in the treatment of inoperable non-small cell lung cancer: a controlled clinical trial

    Radiotherapy remains the basic form of treatment in cases of non-small cell lung cancer (NSCLC) but there still exist controversies concerning optimal radiotherapy regimen and in particular, the total dose and fractionation schedules. To prove whether the question: if using an unconventional dose fractionation regimen (accelerated hyperfractionation) could improve the results of palliative teleradiotherapy patients with NSCLC. Between 1997 and 2000 in the Cancer Centre in Cracow (COOK) a controlled clinical trial was conducted in a group of 150 patients with locally advanced (III Deg) inoperable and unsuitable for radical radiotherapy NSCLC, with no major symptoms of the disease. In 76 patients conventionally fractionated radiotherapy was performed - 50 Gy in 25 fractions during 5 weeks (CF). 74 patients were irradiated twice a day (AHF); the dose per fraction was 1.25 Gy and the minimum interval between fractions - 6 hours. The total dose was 50 Gy in 40 fractions during 26 days. The probability of 12 months survival was 47.4% in the CF arm and 45.9% in the AHF arm; the probability of 24 months survival was 16.2% and 15.8%, respectively. In all 76 patients in CF arm the treatment was carried out in prescribed time without breaks. Out of 74 patients in the A HF group 8 (10,8%) did not complete the treatment and 2 of then died in 3rd and 4th week of treatment. The use of accelerated hyperfractionation does not improve the results of palliative teleradiotherapy in patients with locally advanced NSCLC without severe symptoms related to intrathoracic tumor. The treatment of choice in this group of patients os conventionally fractionated radiotherapy with a total dose of 50 Gy in 25 fractions in 5 week of treatment. (author)

  7. Accelerated versus conventional fractionated postoperative radiotherapy for advanced head and neck cancer: Results of a multicenter Phase III study

    Purpose: To determine whether, in the postoperative setting, accelerated fractionation (AF) radiotherapy (RT) yields a superior locoregional control rate compared with conventional fractionation (CF) RT in locally advanced squamous cell carcinomas of the oral cavity, oropharynx, larynx, or hypopharynx. Methods and materials: Patients from four institutions with one or more high-risk features (pT4, positive resection margins, pN >1, perineural/lymphovascular invasion, extracapsular extension, subglottic extension) after surgery were randomly assigned to either RT with one daily session of 2 Gy up to 60 Gy in 6 weeks or AF. Accelerated fractionation consisted of a 'biphasic concomitant boost' schedule, with the boost delivered during the first and last weeks of treatment, to deliver 64 Gy in 5 weeks. Informed consent was obtained. The primary endpoint of the study was locoregional control. Analysis was on an intention-to-treat basis. Results: From March 1994 to August 2000, 226 patients were randomized. At a median follow-up of 30.6 months (range, 0-110 months), 2-year locoregional control estimates were 80% ± 4% for CF and 78% ± 5% for AF (p = 0.52), and 2-year overall survival estimates were 67% ± 5% for CF and 64% ± 5% for AF (p = 0.84). The lack of difference in outcome between the two treatment arms was confirmed by multivariate analysis. However, interaction analysis with median values as cut-offs showed a trend for improved locoregional control for those patients who had a delay in starting RT and who were treated with AF compared with those with a similar delay but who were treated with CF (hazard ratio = 0.5, 95% confidence interval 0.2-1.1). Fifty percent of patients treated with AF developed confluent mucositis, compared with only 27% of those treated with CF (p = 0.006). However, mucositis duration was not different between arms. Although preliminary, actuarial Grade 3+ late toxicity estimates at 2 years were 18% ± 4% and 27% ± 6% for CF and AF

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

    To present our experience of intensity-modulated radiotherapy (IMRT) with simultaneous modulated accelerated radiotherapy (SMART) boost technique in patients with nasopharyngeal carcinoma (NPC). Sixty eight patients of NPC were treated between April 2006 and December 2011 including 45 males and 23 females with mean age of 46 (range 15–78). Stage distribution was; stage I 3, stage II 7, stage III 26 and stage IV 32. Among 45 (66.2%) evaluated patients for presence of Epstein-Barr virus (EBV), 40 (88.8%) were positive for EBV. Median radiation doses delivered to gross tumor volume (GTV) and positive neck nodes were 66–70 Gy, 63 Gy to clinical target volume (CTV) and 50.4 Gy to clinically negative neck. In addition 56 (82.4%) patients with bulky tumors (T4/N2+) received neoadjuvant chemotherapy 2–3 cycles (Cisplatin/Docetaxel or Cisplatin/Epirubicin or Cisplatin/5 Flourouracil). Concurrent chemotherapy with radiation was weekly Cisplatin 40 mg/m2 (40 patients) or Cisplatin 100 mg/m2 (28 patients). With a median follow up of 20 months (range 3–43), one patient developed local recurrence, two experienced regional recurrences and distant failure was seen in 3 patients. Estimated 3 year disease free survival (DFS) was 94%. Three year DFS for patients with EBV was 100% as compared to 60% without EBV (p = 0.0009). Three year DFS for patients with undifferentiated histology was 98% as compared to 82% with other histologies (p = 0.02). Acute grade 3 toxicity was seen as 21 (30.9%) having G-III mucositis and 6 (8.8%) with G-III skin reactions. Late toxicity was minimal and loss of taste was seen in 3 patients (7.5%) at time of analysis. IMRT with SMART in combination with chemotherapy is feasible and effective in terms of both the clinical response and safety profile. EBV, histopathology and nodal involvement were found important prognostic factors for locoregional recurrence

  9. Radiobiological Characterization of Two Photon-Beam Energies 6 and 15 MV used in Radiotherapy From Linear Accelerator

    The main objective of this study is to perform radiobiological characterization of two different photon beam energies, 6 MV and 15 MV, from linear accelerator used in radiotherapy, with special regard to late effects of radiation. Two end-points, namely cell survival and micronucleus induction were used for the characterization. Chinese hamster V 79 lung fibroblast cell line to prepare cell culture and to perform the innervate experiments. chromosomes number was counted and found to be 22 chromosomes per cell, this result is in complete agreement with expected 11 pairs of chromosomes representing the genome of this species. Cells were kept in confluent growth for two days and then exposed to two photon beam energies, 6 and 15 MV respectively. Different dose rates were used for the two beam energies, 0.25, 0.5, 1.0, 2.0, 4.0, 7.0 Gy. Cells were counted immediately after irradiation and re seeded, the seeded number of cells was calculated to the dose rate used. Another set of unirradiated cells treated the same as the experimental set was used as a control group. The plating efficiency (PE) was calculated for the control group, then cells were incubated at 37oC for 6 days to construct the survival curve, five samples were counted per dose and the mean was calculated. The two survival curves are similar for photon beam energies (6 and 15 MV) and the surviving fraction was decreased with dose rate. The two curves showed similar values of α and β parameters, this result is expected for the same radiation type (X-ray). For the micronuclei assay three samples for each dose were seeded and incubated at 37oC for 24 hours then Cytochalasin-B was added to block cells in cytokinesis phase of the mitosis. The micronuclei number was counted and plotted with dose. A significant positive correlation was found between dose and micronuclei frequency (P=0.00), moreover, the micronuclei frequency is relatively higher with 15 MV compared with 6 MV energy. This indicates the presence

  10. TLD Intercomparison in accelerators for radiotherapy in three Latin american countries; Intercomparacion TLD en aceleradores para radioterapia en tres paises latinoamericanos

    Gaona, E.; Azorin N, J.; Perez, M.A.; Picon, C.; Castellanos, E.; Plazas, M.C.; Murcia, G.; Archundia, L. [Depto. El Hombre y su Ambiente. Universidad Autonoma Metropolitana, Calz. Del Hueso 1100, 04960 Mexico D.F. (Mexico)

    1998-12-31

    In Radiotherapy one of the objectives is to establish and to give follow up to quality assurance programs which make sure that the doses administered to the patients with cancer are a high probability of a success in external radiation. Likewise, one of the present preoccupations of the United Nations Agencies as well as the International Atomic Energy Agency and the Pan-American Health Organization is the optimal employment of the radiations in the treatment of cancer patients since the administered dose in Radiotherapy suffers considerable variations by the lack of quality assurance programs. The use of Electron linear accelerators requires a program of quality assurance that includes expert personnel, equipment and adequate facilities. The more used methodology for the dosimetry calibration and characterization of X-ray beams and high energy electrons for radiotherapy use is using a ionization chamber dosemeter calibrated in a regional secondary standardization laboratory. However, to establish and give follow up to the quality assurance programs it is necessary the dosimetric intercomparison through TLD. In this study it was designed plastic phantoms with TLD crystals and it was made its characterization to realize an absorbed dose analysis in the crystals exposed at X-ray beams 6 MV and high energy electrons 10 and 12 MeV to standardize the dosimetric procedures and proceeding to realize an International Pilot intercomparison of absorbed doses in TLD crystals in three Latin American countries: Mexico, Peru and Colombia with the participation of accelerators of five different institutions. The found results show that the majority of the measured doses with TLD in the different accelerators were in the 0.95-1.05 range though it had two cases outside of this range. The use of the phantoms with TLD crystals shows that they are of excellent aid to make analysis of the doses administered to the patients and an intercomparison of results to standardize procedures at

  11. Carbogen Breathing Differentially Enhances Blood Plasma Volume and 5-Fluorouracil Uptake in Two Murine Colon Tumor Models with a Distinct Vascular Structure

    Hanneke W.M. van Laarhoven

    2006-06-01

    Full Text Available For the systemic treatment of colorectal cancer, 5-fluorouracil (FU-based chemotherapy is the standard. However, only a subset of patients responds to chemotherapy. Breathing of carbogen (95% O2 and 5% CO2 may increase the uptake of FU through changes in tumor physiology. This study aims to monitor in animal models in vivo the effects of carbogen breathing on tumor blood plasma volume, pH, and energy status, and on FU uptake and metabolism in two colon tumor models C38 and C26a, which differ in their vascular structure and hypoxic status. Phosphorus-31 magnetic resonance spectroscopy (MRS was used to assess tumor pH and energy status, and fluorine-19 MRS was used to follow FU uptake and metabolism. Advanced magnetic resonance imaging methods using ultrasmall particles of iron oxide were performed to assess blood plasma volume. The results showed that carbogen breathing significantly decreased extracellular pH and increased tumor blood plasma volume and FU uptake in tumors. These effects were most significant in the C38 tumor line, which has the largest relative vascular area. In the C26a tumor line, carbogen breathing increased tumor growth delay by FU. In this study, carbogen breathing also enhanced systemic toxicity by FU.

  12. Impact on cellular immunocompetence by late course accelerated hyperfractionation radiotherapy assisted with cisplatin in the treatment of esophageal carcinoma

    Objective: To investigate the therapeutic results of late course accelerated hyperfractionation radiotherapy (LCAHR) combined with concomitant cisplatin administration as a sensitizer, and to assess the effects on cell-mediated immunocompetence in the treatment of esophageal carcinoma. Methods: From Jan. to Nov. 199, 104 patients with squamous cell carcinoma (SCC) of the esophagus were randomized to receive LCAHR alone (Group A, 53 patients) or LCAHR plus cisplatin (Group B, 51 patients). For both groups, the same radiation technic was given with the conventional fractionation in the first 3 weeks and 1.5 Gy twice daily, a minimum inter fraction interval of 6 hours, 5 days per week in the final 2 weeks. The total dose was 60 Gy/35 fs/5 wk. For the B group patients, cisplatin was given synchronously with 20 mg once daily for 5 days in the 1 st and 5 th weeks. The CD4, CD8 and CD56 expressions in peripheral blood lymphocytes (PBL) were quantitatively assessed with flow cytometry before and during the treatment. Results: The CD4/CD8 ratio of PBL decreased significantly after treatment completion (P < 0.01 in Group A and P < 0.01 in Group B). Whereas the percentage of positive CD56 PBL increased dramatically (P < 0.01 in two groups). There were no evidence that CD expression difference had any statistical or clinical significance. Conclusion: Immunosuppression may be present on cell-mediated immuno-activity (CD4/CD8) and NK cell (CD56)immuno-enhancement may be obtainable on immuno-surveillance, when esophageal carcinoma is being treated by LCAHR with or without cisplatin

  13. Neoadjuvant short-course hyperfractionated accelerated radiotherapy (SC-HART) combined with S-1 for locally advanced rectal cancer

    The purpose of this study was to examine the safety and feasibility of a novel protocol of neoadjuvant short-course hyperfractionated accelerated radiotherapy (SC-HART) combined with S-1 for locally advanced rectal cancer. A total of 56 patients with lower rectal cancer of cT3N1M0 (Stage III b) was treated with SC-HART followed by radical surgery, and were analyzed in the present study. SC-HART was performed with a dose of 2.5 Gy twice daily, with an interval of at least 6 hours between fractions, up to a total dose of 25 Gy (25 Gy in 10 fractions for 5 days) combined with S-1 for 10 days. Radical surgery was performed within three weeks following the end of the SC-HART. The median age was 64.6 (range, 39-85) years. The median follow-up term was 16.3 (range, 2-53) months. Of the 56 patients, 53 (94.4%) had no apparent adverse events before surgery; 55 (98.2%) completed the full course of neoadjuvant therapy, while one patient stopped chemotherapy because of Grade 3 gastrointestinal toxicity (CTCAE v.3). The sphincter preservation rate was 94.6%. Downstaging was observed in 45 patients (80.4%). Adjuvant chemotherapy was administered to 43 patients (76.8%). The local control rate, disease-free survival rate and disease-specific survival rate were 100%, 91.1% and 100%, respectively. To conclude, SC-HART combined with S-1 for locally advanced rectal cancer was well tolerated and produced good short-term outcomes. SC-HART therefore appeared to have a good feasibility for use in further clinical trials. (author)

  14. Neoadjuvant short-course hyperfractionated accelerated radiotherapy (SC-HART) combined with S-1 for locally advanced rectal cancer.

    Doi, Hiroshi; Beppu, Naohito; Odawara, Soichi; Tanooka, Masao; Takada, Yasuhiro; Niwa, Yasue; Fujiwara, Masayuki; Kimura, Fumihiko; Yanagi, Hidenori; Yamanaka, Naoki; Kamikonya, Norihiko; Hirota, Shozo

    2013-11-01

    The purpose of this study was to examine the safety and feasibility of a novel protocol of neoadjuvant short-course hyperfractionated accelerated radiotherapy (SC-HART) combined with S-1 for locally advanced rectal cancer. A total of 56 patients with lower rectal cancer of cT3N1M0 (Stage III b) was treated with SC-HART followed by radical surgery, and were analyzed in the present study. SC-HART was performed with a dose of 2.5 Gy twice daily, with an interval of at least 6 hours between fractions, up to a total dose of 25 Gy (25 Gy in 10 fractions for 5 days) combined with S-1 for 10 days. Radical surgery was performed within three weeks following the end of the SC-HART. The median age was 64.6 (range, 39-85) years. The median follow-up term was 16.3 (range, 2-53) months. Of the 56 patients, 53 (94.4%) had no apparent adverse events before surgery; 55 (98.2%) completed the full course of neoadjuvant therapy, while one patient stopped chemotherapy because of Grade 3 gastrointestinal toxicity (CTCAE v.3). The sphincter preservation rate was 94.6%. Downstaging was observed in 45 patients (80.4%). Adjuvant chemotherapy was administered to 43 patients (76.8%). The local control rate, disease-free survival rate and disease-specific survival rate were 100%, 91.1% and 100%, respectively. To conclude, SC-HART combined with S-1 for locally advanced rectal cancer was well tolerated and produced good short-term outcomes. SC-HART therefore appeared to have a good feasibility for use in further clinical trials. PMID:23658415

  15. Whole brain radiotherapy: Prognostic factors and results of a radiation boost delivered through a conventional linear accelerator

    Purpose: Assess prognostic factors for overall survival and the potential benefit of a boost in patients treated with whole brain radiation therapy (WBRT). Methods and materials: From 2002 to 2006, a retrospective analysis was made from 250 unselected consecutive patients with secondary brain metastases from lung cancer, breast cancer and melanoma. Eighteen patients received surgery and were excluded from analysis. Four potential prognostic factors have been studied: primary tumor type, gender, number of metastases and improvement of neurological symptoms after radiation therapy. A subgroup analysis was performed to determine whether an additional boost could potentially improve outcome in patients who presented with less than three metastases, performance status <2, and no surgical resection of their metastasis. Results: Average follow-up was 10.3 months. Median overall survival was 5.6 months and survival rates at 1 and 2 years were 22.7% and 10%, respectively. Age less than 65 (p < 0.01), neurological improvement after WBRT (p < 0.01), and presence of less than three metastases were significant factors for overall survival in multivariate analysis. When focusing on the selected subgroup (120 assessable patients), median overall survival was 4.0 months in patients with no radiation boost, versus 8.9 months in patients with radiation boost (p = 0.0024). Conclusions: Survival and prognostic factors were similar to those found in the literature. Boost delivered after WBRT by a conventional particle accelerator could provide a benefit in selected patients, especially for centers that do not have radiotherapy techniques in stereotactic conditions. This warrants further prospective assessment.

  16. Quality assurance audit in an Australasian phase III trial of accelerated radiotherapy for head and neck cancer (TROG 91.01)

    The Trans-Tasman Radiation Oncology Group (TROG) initiated a randomized trial, testing accelerated (twice daily) radiotherapy against conventional radiotherapy for stage II and stage IV squamous cell carcinoma of the head and neck in 1991. In 1996, the Trial Management Committee arranged for a technical audit of 76 cases from 11 institutions, conducted by investigators from interstate institutions. A 10% unacceptable protocol violation rate was detected, which compares favourably with initial Radiation Therapy Oncology Group (RTOG) experience in the late 1970s. Infrastructural deficits with poor quality of documentation, incomplete retrieval of films and document return have been demonstrated in some cases. The Trans-Tasman Radiation Oncology Group is actively pursuing procedural and resourcing issues in order to redress this and is actively expanding its Quality Assurance (QA) Programme with an intercentre dosimetry study. Ultimately, comprehensive clinical and technical QA site visits are planned. Copyright (1999) Blackwell Science Pty Ltd

  17. Evaluation and Immunohistochemical Qualification of Carbogen-Induced ΔR{sub 2}* as a Noninvasive Imaging Biomarker of Improved Tumor Oxygenation

    Baker, Lauren C.J., E-mail: lauren.baker@icr.ac.uk [Cancer Research UK and EPSRC Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom); Boult, Jessica K.R.; Jamin, Yann; Gilmour, Lesley D.; Walker-Samuel, Simon; Burrell, Jake S. [Cancer Research UK and EPSRC Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom); Ashcroft, Margaret [Division of Medicine, Centre for Cell Signalling and Molecular Genetics, University College London, London (United Kingdom); Howe, Franklyn A. [St. George' s, University of London, London (United Kingdom); Griffiths, John R. [Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Raleigh, James A. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina (United States); Kogel, Albert J. van der [University of Nijmegen Medical Centre, Nijmegen (Netherlands); Robinson, Simon P. [Cancer Research UK and EPSRC Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom)

    2013-09-01

    Purpose: To evaluate and histologically qualify carbogen-induced ΔR{sub 2}* as a noninvasive magnetic resonance imaging biomarker of improved tumor oxygenation using a double 2-nitroimidazole hypoxia marker approach. Methods and Materials: Multigradient echo images were acquired from mice bearing GH3 prolactinomas, preadministered with the hypoxia marker CCI-103F, to quantify tumor R{sub 2}* during air breathing. With the mouse remaining positioned within the magnet bore, the gas supply was switched to carbogen (95% O{sub 2}, 5% CO{sub 2}), during which a second hypoxia marker, pimonidazole, was administered via an intraperitoneal line, and an additional set of identical multigradient echo images acquired to quantify any changes in tumor R{sub 2}*. Hypoxic fraction was quantified histologically using immunofluorescence detection of CCI-103F and pimonidazole adduct formation from the same whole tumor section. Carbogen-induced changes in tumor pO{sub 2} were further validated using the Oxylite fiberoptic probe. Results: Carbogen challenge significantly reduced mean tumor R{sub 2}* from 116 ± 13 s{sup −1} to 97 ± 9 s{sup −1} (P<.05). This was associated with a significantly lower pimonidazole adduct area (2.3 ± 1%), compared with CCI-103F (6.3 ± 2%) (P<.05). A significant correlation was observed between ΔR{sub 2}* and Δhypoxic fraction (r=0.55, P<.01). Mean tumor pO{sub 2} during carbogen breathing significantly increased from 6.3 ± 2.2 mm Hg to 36.0 ± 7.5 mm Hg (P<.01). Conclusions: The combined use of intrinsic susceptibility magnetic resonance imaging with a double hypoxia marker approach corroborates carbogen-induced ΔR{sub 2}* as a noninvasive imaging biomarker of increased tumor oxygenation.

  18. Preliminary comparison of the therapeutic efficacy of accelerated relative to conventional fractionation radiotherapy by treatment of spontaneous canine malignancies

    Purpose/Objective: This study's ultimate goals involve development of an accelerated fractionation (AF) regimen with an integrated final concomitant boost (CB) and examination of factors prognostic of the CB's therapeutic efficacy which could be measured during the initial AF portion to determine for which patients CB should be used. These endpoints can be accurately determined quickly by evaluating the treatment (tx) of spontaneous canine veterinary patient tumors. Because surviving tumor clonogen growth rate increases after radiotherapy (RT) begins, this accelerated repopulation (AR) should be reduced by AF. Furthermore, CB using a small field encompassing only the tumor bed, given as a second daily tx during the last week of RT, should further reduce AR. The initial portion of this project which is nearing completion was designed to determine if incidentally treated normal tissues could tolerate the AF regimen and project whether addition of the tumor bed CB would also be tolerated. Materials and Methods: Currently 20 canine patients with biopsy proven localized tumors have received canine AF radiotherapy given as 3.2Gy/fraction(fx) administered 5 days a week (Mon-Fri) to a total of 15 fxs (48Gy) within 18 elapsed days. RT is given with a 60Co teletherapy unit. Their tumor response, control, survival, and acute normal tissue responses are being directly compared to results we previously obtained from canines receiving a nearly equivalent dose/fx and total dose conventional fractionation (CF) regimen which was given alone or with adjuvant hyperthermia (HT). In that study the canines were stratified by tumor histology and anatomic site and randomly assigned to receive canine CF (3.5Gy/fx, 3 fxs/week [Mon-Wed-Fri] to 14 fxs (49Gy) in an elapsed time of approx. 30 days) either alone or followed weekly by local HT (44 deg. +/- 2 deg. C) for 30 minutes (5 HT fxs). As is currently done, these CF+/-HT patients were followed up to 3 years to quantitate the magnitudes and

  19. Experimental research of dose distribution and protection for mobile intra-operative radiotherapy accelerator in operating room

    Objective: To study the dose distribution characteristics for mobile intra-operative radiotherapy accelerator (Mobetron) in an operating room, and to provide basic data for developing appropriate radiation protection measures and protection standard. Methods: For most commonly used electron energy 9 MeV, TLD dosimeters were placed at 50, 100, 150 and 200 cm high plane, respectively. For each plane,the measurement points were selected at every 50 cm from the central axis at every 45° at eight different directions. Also different electron energies, such as 4, 6, 9 and 12 MeV, were taken into consideration at the plane at 100 cm height. After 10 Gy with a dose rate of 10 Gy/min were delivered, the TLD dosimeters were used to read out the data. Results: For 9 MeV, at the phantom plane (100 cm high plane), the average doses were 169, 756, 395 and 241 μSv at 50, 100, 150 and 200 cm from the central axis,respectively. The maximum deviation between the doses at 50 cm from the central axis in different angles and their average values were 9.1%. In the identical angle, the average doses of 50, 100, 150 and 200 cm high planes at the distance of 100 cm from central axis were 527, 756, 570 and 141 μSv, respectively. For the energies of 4, 6, 9 and 12 MeV, the average doses were 573, 486, 689 and 781 μSv at 100 cm from the central axis at 90° of 100 cm high plane. Conclusions: For the same energy,the dose values at different directions were decreased by the minus exponential function law with the distance. The doses were uniformly distributed at different directions at the same distance from the central axis. The doses on the plane of 100 cm height were much higher than those at other heights,and the dose values were increased with the election energy. (authors)

  20. Development of an ultrasmall C-band linear accelerator guide for a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head.

    Kamino, Yuichiro; Miura, Sadao; Kokubo, Masaki; Yamashita, Ichiro; Hirai, Etsuro; Hiraoka, Masahiro; Ishikawa, Junzo

    2007-05-01

    We are developing a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head. It is capable of pursuing irradiation and delivering irradiation precisely with the help of an agile moving x-ray head on the gimbals. Requirements for the accelerator guide were established, system design was developed, and detailed design was conducted. An accelerator guide was manufactured and basic beam performance and leakage radiation from the accelerator guide were evaluated at a low pulse repetition rate. The accelerator guide including the electron gun is 38 cm long and weighs about 10 kg. The length of the accelerating structure is 24.4 cm. The accelerating structure is a standing wave type and is composed of the axial-coupled injector section and the side-coupled acceleration cavity section. The injector section is composed of one prebuncher cavity, one buncher cavity, one side-coupled half cavity, and two axial coupling cavities. The acceleration cavity section is composed of eight side-coupled nose reentrant cavities and eight coupling cavities. The electron gun is a diode-type gun with a cerium hexaboride (CeB6) direct heating cathode. The accelerator guide can be operated without any magnetic focusing device. Output beam current was 75 mA with a transmission efficiency of 58%, and the average energy was 5.24 MeV. Beam energy was distributed from 4.95 to 5.6 MeV. The beam profile, measured 88 mm from the beam output hole on the axis of the accelerator guide, was 0.7 mm X 0.9 mm full width at half maximum (FWHM) width. The beam loading line was 5.925 (MeV)-Ib (mA) X 0.00808 (MeV/mA), where Ib is output beam current. The maximum radiation leakage of the accelerator guide at 100 cm from the axis of the accelerator guide was calculated as 0.33 cGy/min at the rated x-ray output of 500 cGy/min from the measured value. This leakage requires no radiation shielding for the accelerator guide itself per IEC 60601-2-1. PMID:17555261

  1. IAEA-HypoX. A randomized multicenter study of the hypoxic radiosensitizer nimorazole concomitant with accelerated radiotherapy in head and neck squamous cell carcinoma

    Metwally, Mohamed Ahmed Hassan; Ali, Rubina; Kuddu, Maire;

    2015-01-01

    multicenter randomized trial in patients with HNSCC. Tumors were treated to a dose of 66-70Gy, 33-35 fractions, 6 fractions per week. NIM was administered in a dose of 1.2gperm(2), 90min before the first daily RT fraction. The primary endpoint was loco-regional failure. The trial was closed prematurely by......PURPOSE: To test the hypothesis that radiotherapy (RT) of head and neck squamous cell carcinoma (HNSCC) can be improved by hypoxic modification using nimorazole (NIM) in association with accelerated fractionation. MATERIALS AND METHODS: The protocol was activated in March 2012 as an international...... HNSCC given the hypoxic modifier NIM in addition to accelerated fractionation RT. However, the trial also revealed that conducting multicenter and multinational study combining drug and RT in developing countries may suffer from uncontrolled and unsolvable problems....

  2. High-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in locally advanced non-small-cell lung cancer: a feasibility study

    Increasing the radiotherapy dose can result in improved local control for non-small-cell lung cancer (NSCLC) and can thereby improve survival. Accelerated hypofractionated radiotherapy can expose tumors to a high dose of radiation in a short period of time, but the optimal treatment regimen remains unclear. The purpose of this study was to evaluate the feasibility of utilizing high-dose accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for the treatment of local advanced NSCLC. Untreated patients with unresectable stage IIIA/IIIB NSCLC or patients with a recurrence of NSCLC received accelerated hypofractionated three-dimensional conformal radiotherapy. The total dose was greater than or equal to 60 Gy. The accelerated hypofractionated radiotherapy was conducted once daily at 3 Gy/fraction with 5 fractions per week, and the radiotherapy was completed in 5 weeks. In addition to radiotherapy, the patients also received at least 1 cycle of a concurrent two-drug chemotherapy regimen of NVB and CBP. A total of 26 patients (19 previously untreated cases and 7 cases of recurrent disease) received 60Gy-75Gy radiotherapy with concurrent chemotherapy. All of the patients underwent evaluations for toxicity and preliminary therapeutic efficacy. There were no treatment-related deaths within the entire patient group. The major acute adverse reactions were radiation esophagitis (88.5%) and radiation pneumonitis (42.3%). The percentages of grade III acute radiation esophagitis and grade III radiation pneumonitis were 15.4% and 7.7%, respectively. Hematological toxicities were common and did not significantly affect the implementation of chemoradiotherapy after supportive treatment. Two patients received high dose of 75 Gy had grade III late esophageal toxicity, and none had grade IV and above. Grade III and above late lung toxicity did not occur. High-dose accelerated

  3. Clinical role of18F-FDG PET/CT-based simultaneous modulated accelerated radiotherapy treatment plan-ning for locally advanced nasopharyngeal carcinoma

    Jianshe Wang; Tianyou Tang Co-first author; Jing Xu; Andrew Z Wang; Liang Li; Junnian Zheng; Longzhen Zhang

    2015-01-01

    Objective The aim of this study was to compare the long-term local control, overal survival, and late toxicities of positron emission tomography/computed tomography (PET/CT)-guided dose escalation radio-therapy versus conventional radiotherapy in the concurrent chemoradiotherapy treatment of local y ad-vanced nasopharyngeal carcinoma (NPC). Methods A total of 48 patients with stage III–IVa NPC were recruited and randomly administered PET/CT-guided dose escalation chemoradiotherapy (group A) or conventional chemoradiotherapy (group B). The dose-escalation radiotherapy was performed using the simultaneous modulated accelerated radiotherapy technique at prescribed doses of 77 gray (Gy) in 32 fractions (f) to the gross target volume (GTV): planning target volume (PTV) 1 received 64 Gy/32 f, while PTV2 received 54.4 Gy/32 f. Patients in group B received uniform-dose intensity-modulated radiotherapy, PTV1 received 70 Gy/35 f and PTV2 received 58 Gy/29 f. Concurrent chemotherapy consisted of cisplatin [20 mg/m2 intravenous (IV) on days 1–4] and docetaxel (75 mg/m2 IV on days 1 and 8) administered during treatment weeks 1 and 4. Al patients received 2–4 cycles of adjuvant chemotherapy of the same dose and drug regimen. Results The use of fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT significantly reduced the treat-ment volume delineation of the GTV in 83.3% (20/24) of patients. The 5-year local recurrence-free survival rates of the two groups were 100% and 79.2%, respectively (P = 0.019). The 5-year disease free survival (DFS) rates were 95.8% and 75.0%, respectively (P = 0.018). The 5-year local progression-free survival and DFS rates were significantly dif erent. The 5-year overal survival (OS) rates were 95.8% and 79.2%, re-spectively. Dif erences in OS improvement were insignificant (P = 0.079). Late toxicities were similar in the two groups. The most common late toxicities of the two arms were grade 1–2 skin dystrophy, xerostomia, subcutaneous fibrosis, and

  4. Accelerator

    The invention claims equipment for stabilizing the position of the front covers of the accelerator chamber in cyclic accelerators which significantly increases accelerator reliability. For stabilizing, it uses hydraulic cushions placed between the electromagnet pole pieces and the front chamber covers. The top and the bottom cushions are hydraulically connected. The cushions are disconnected and removed from the hydraulic line using valves. (J.P.)

  5. Hyperfractionated accelerated radiotherapy with concomitant integrated boost of 70-75 Gy in 5 weeks for advanced head and neck cancer. A phase I dose escalation study

    Cvek, J.; Skacelikova, E.; Otahal, B.; Halamka, M.; Feltl, D. [University Hospital Ostrava (Czech Republic). Dept. of Oncology; Kubes, J. [University Hospital Bulovka, Prague (Czech Republic). Dept. of Radiation Oncology; Kominek, P. [University Hospital Ostrava (Czech Republic). Dept. of Otolaryngology

    2012-08-15

    Background and purpose: The present study was performed to evaluate the feasibility of a new, 5-week regimen of 70-75 Gy hyperfractionated accelerated radiotherapy with concomitant integrated boost (HARTCIB) for locally advanced, inoperable head and neck cancer. Methods and materials: A total of 39 patients with very advanced, stage IV nonmetastatic head and neck squamous cell carcinoma (median gross tumor volume 72 ml) were included in this phase I dose escalation study. A total of 50 fractions intensity-modulated radiotherapy (IMRT) were administered twice daily over 5 weeks. Prescribed total dose/dose per fraction for planning target volume (PTV{sub tumor}) were 70 Gy in 1.4 Gy fractions, 72.5 Gy in 1.45 Gy fractions, and 75 Gy in 1.5 Gy fractions for 10, 13, and 16 patients, respectively. Uninvolved lymphatic nodes (PTV{sub uninvolved}) were irradiated with 55 Gy in 1.1 Gy fractions using the concomitant integrated boost. Results: Acute toxicity was evaluated according to the RTOG/EORTC scale; the incidence of grade 3 mucositis was 51% in the oral cavity/pharynx and 0% in skin and the recovery time was {<=} 9 weeks for all patients. Late toxicity was evaluated in patients in complete remission according to the RTOG/EORTC scale. No grade 3/4 late toxicity was observed. The 1-year locoregional progression-free survival was 50% and overall survival was 55%. Conclusion: HARTCIB (75 Gy in 5 weeks) is feasible for patients deemed unsuitable for chemoradiation. Acute toxicity was lower than predicted from radiobiological models; duration of dysphagia and confluent mucositis were particularly short. Better conformity of radiotherapy allows the use of more intensive altered fractionation schedules compared with older studies. These results suggest that further dose escalation might be possible when highly conformal techniques (e.g., stereotactic radiotherapy) are used.

  6. Advances in conformal radiotherapy using Monte Carlo Code to design new IMRT and IORT accelerators and interpret CT numbers

    Wysocka-Rabin, A

    2013-01-01

    The introductory chapter of this monograph, which follows this Preface, provides an overview of radiotherapy and treatment planning. The main chapters that follow describe in detail three significant aspects of radiotherapy on which the author has focused her research efforts. Chapter 2 presents studies the author worked on at the German National Cancer Institute (DKFZ) in Heidelberg. These studies applied the Monte Carlo technique to investigate the feasibility of performing Intensity Modulated Radiotherapy (IMRT) by scanning with a narrow photon beam. This approach represents an alternative to techniques that generate beam modulation by absorption, such as MLC, individually-manufactured compensators, and special tomotherapy modulators. The technical realization of this concept required investigation of the influence of various design parameters on the final small photon beam. The photon beam to be scanned should have a diameter of approximately 5 mm at Source Surface Distance (SSD) distance, and the penumbr...

  7. Quality of life assessment in advanced non-small-cell lung cancer patients undergoing an accelerated radiotherapy regimen: report of ECOG study 4593

    Purpose: To prospectively evaluate the quality of life (QOL) before, at completion, and after therapy for patients receiving an accelerated fractionation schedule of radiotherapy for advanced, unresectable non-small-cell lung cancer in a Phase II multi-institutional trial. Methods and Materials: The Functional Assessment of Cancer Therapy-Lung (FACT-L) patient questionnaire was used to score the QOL in patients enrolled in the Eastern Cooperative Oncology Group Phase II trial (ECOG 4593) of hyperfractionated accelerated radiotherapy in non-small-cell lung cancer. Radiotherapy (total dose 57.6 Gy in 36 fractions) was delivered during 15 days, with three radiation fractions given each treatment day. The protocol was activated in 1993, and 30 patients had accrued by November 1995. The FACT-L questionnaire was administered at study entry (baseline), on the last day of radiotherapy (assessment 2), and 4 weeks after therapy (assessment 3). The FACT-L includes scores for physical, functional, emotional, and social well-being (33 items), and a subscale of lung cancer symptoms (10 additional items). The summation of the physical, functional, and lung cancer symptom subscales (21 items) constitutes the Trial Outcome Index (TOI), considered the most clinically relevant outcome measure in lung cancer treatment trials. Results: The FACT-L completion rates at the designated study time points were as follows: baseline, 30 of 30 (100%); assessment 2, 29 (97%) of 30; and assessment 3, 24 (80%) of 30. At treatment completion, statistically significant declines in QOL scores were noted, compared with baseline for physical and functional well-being. Emotional well-being scores improved at both assessment 2 and assessment 3. The physical and functional scores returned approximately to baseline values at assessment 3. The change in TOI score was evaluated as a function of the clinical response to treatment, toxicity grade, and survival; no clear association was noted. A trend for the

  8. A Randomized Study of Accelerated Fractionation Radiotherapy with and Without Mitomycin C in the Treatment of Locally Advanced Head and Neck Cancer

    This single-institution study evaluates the feasibility of accelerated fractionation radiotherapy (AF) with and without mitomycin C (MMC) in thc treatment of locally advanced head and neck cancer. Patients and Methods: Between May 1998 and October 2001, sixty patients with locally advanced stage III and IV of head and neck cancer were randomized into three treatment arms: (I) conventional fractionation radiotherapy (CF) (5 fractions per week); (2) accelerated fractionation radiotherapy (AF) (6 fractions per week); and (3) AF plus Mitomycin C (MMC). The 2-year overall survival (OS) of the whole group was 21 %. The OS according to treatment arm was 23%, 20%. and 28% in CF. AF. and AF+MMC arms respectively (ρ<0. 19). The 2-year loco-regional control (LC) rate was 22% for the whole group of patients. The LC was 10%, 25%. and 30% for the CF, AF, and AF+MMC respectively (ρ=0.27). The only significant parameters for OS and LC were performance status and pre-treatment hemoglobin level. Mucositis grades 3 and 4 occurred in 70% and 90% of the patients in the AF and AF+MMC arm respectively compared to 55% of patients in the CF arm (ρ=0.04). However the addition of MMC did not significantly increase the incidence or severity of mucositis between AF and AF+MMC (ρ=0.13). Hematological toxicity grades 3 and 4 were significantly higher after MMC (occurred in 40% of patients versus 10% and 5% in CF and AF arms respectively, ρ=0.04). There was no statistically significant difference in the incidence of grade 3 dryness of mouth (ρ=0.06). fibrosis (ρ=0.6). or lymphoedema (ρ=0.39) among the three arms. There was a trend for improvement of LC and OS rates with the use or AF and the addition of MMC to AF compared to CF radiotherapy. although the difference was not statistically significant. The small number of the patients in each treatment arm and the inclusion or multiple tumor sites may contribute to these statistically insignificant results. Accordingly we advise to continue

  9. Normal tissue complication models for clinically relevant acute esophagitis (≥ grade 2) in patients treated with dose differentiated accelerated radiotherapy (DART-bid)

    One of the primary dose-limiting toxicities during thoracic irradiation is acute esophagitis (AE). The aim of this study is to investigate dosimetric and clinical predictors for AE grade ≥ 2 in patients treated with accelerated radiotherapy for locally advanced non-small cell lung cancer (NSCLC). 66 NSCLC patients were included in the present analysis: 4 stage II, 44 stage IIIA and 18 stage IIIB. All patients received induction chemotherapy followed by dose differentiated accelerated radiotherapy (DART-bid). Depending on size (mean of three perpendicular diameters) tumors were binned in four dose groups: <2.5 cm 73.8 Gy, 2.5–4.5 cm 79.2 Gy, 4.5–6 cm 84.6 Gy, >6 cm 90 Gy. Patients were treated in 3D target splitting technique. In order to estimate the normal tissue complication probability (NTCP), two Lyman models and the cutoff-logistic regression model were fitted to the data with AE ≥ grade 2 as statistical endpoint. Inter-model comparison was performed with the corrected Akaike information criterion (AICc), which calculates the model’s quality of fit (likelihood value) in relation to its complexity (i.e. number of variables in the model) corrected by the number of patients in the dataset. Toxicity was documented prospectively according to RTOG. The median follow up was 686 days (range 84–2921 days), 23/66 patients (35 %) experienced AE ≥ grade 2. The actuarial local control rates were 72.6 % and 59.4 % at 2 and 3 years, regional control was 91 % at both time points. The Lyman-MED model (D50 = 32.8 Gy, m = 0.48) and the cutoff dose model (Dc = 38 Gy) provide the most efficient fit to the current dataset. On multivariate analysis V38 (volume of the esophagus that receives 38 Gy or above, 95 %-CI 28.2–57.3) was the most significant predictor of AE ≥ grade 2 (HR = 1.05, CI 1.01–1.09, p = 0.007). Following high-dose accelerated radiotherapy the rate of AE ≥ grade 2 is slightly lower than reported for concomitant radio-chemotherapy with the

  10. Dosimetric Characteristics of Circular 6-MeV X-Ray Beams for Stereotactic Radiotherapy with a Linear Accelerator

    Wysocka, A.; Rostkowska, J.; Kania, M.; Bulski, W.; Fijuth, J.

    2000-01-01

    Dosimetric characteristics of 6 MeV circular X-ray beams of diameters ranging from 7.5 to 35.0 mm are reported. The 6-MeV X-ray beam from Clinac 2300CD was formed using additional cylindrical BrainLAB's collimators. The mechanical stability of the entire system was verified. Specific quantities measured include tissue maximum ratios (TMR), beam profiles (off-axis ratios OAR) and relative output factors. Measurements of these parameters were performed in a water phantom using small cylindrical ionization chambers and a diamond detector. Comparison of TMR values measured with the ionization chamber and the diamond detector showed no significant differences. It was shown that the latter yields more accurate results for beam profiles than ionization chambers. The mechanical and dosimetric characteristics of this radiotherapy unit are found to be suitable for stereotactic radiosurgery and radiotherapy.

  11. Breast cancer radiotherapy: controversies and prospectives

    YU Jin-ming; WANG Yong-sheng

    2008-01-01

    @@ Despite consensus on breast cancer radiotherapy, there are still some controversies over post-mastectomy radiotherapy (PMRT) in patients with 1-3 positive lymph nodes, accelerated partial breast irradiation (APBI), appropriate sequence of radiotherapy, chemotherapy and hormonal treatment, and radiotherapy after preoperative systemic therapy.

  12. Analysis of quality control data of eight modern radiotherapy linear accelerators: the short- and long-term behaviours of the outputs and the reproducibility of quality control measurements

    Kapanen, Mika [Radiation and Nuclear Safety Authority (STUK), Laippatie 4, 00881 Helsinki (Finland); Tenhunen, Mikko [Department of Oncology, Helsinki University Central Hospital, Haartmaninkatu 4, 00029 Helsinki (Finland); Haemaelaeinen, Tuomo [Department of Oncology, Helsinki University Central Hospital, Haartmaninkatu 4, 00029 Helsinki (Finland); Sipilae, Petri [Radiation and Nuclear Safety Authority (STUK), Laippatie 4, 00881 Helsinki (Finland); Parkkinen, Ritva [Radiation and Nuclear Safety Authority (STUK), Laippatie 4, 00881 Helsinki (Finland); Jaervinen, Hannu [Radiation and Nuclear Safety Authority (STUK), Laippatie 4, 00881 Helsinki (Finland)

    2006-07-21

    Quality control (QC) data of radiotherapy linear accelerators, collected by Helsinki University Central Hospital between the years 2000 and 2004, were analysed. The goal was to provide information for the evaluation and elaboration of QC of accelerator outputs and to propose a method for QC data analysis. Short- and long-term drifts in outputs were quantified by fitting empirical mathematical models to the QC measurements. Normally, long-term drifts were well ({<=}1%) modelled by either a straight line or a single-exponential function. A drift of 2% occurred in 18 {+-} 12 months. The shortest drift times of only 2-3 months were observed for some new accelerators just after the commissioning but they stabilized during the first 2-3 years. The short-term reproducibility and the long-term stability of local constancy checks, carried out with a sealed plane parallel ion chamber, were also estimated by fitting empirical models to the QC measurements. The reproducibility was 0.2-0.5% depending on the positioning practice of a device. Long-term instabilities of about 0.3%/month were observed for some checking devices. The reproducibility of local absorbed dose measurements was estimated to be about 0.5%. The proposed empirical model fitting of QC data facilitates the recognition of erroneous QC measurements and abnormal output behaviour, caused by malfunctions, offering a tool to improve dose control.

  13. Analysis of quality control data of eight modern radiotherapy linear accelerators: the short- and long-term behaviours of the outputs and the reproducibility of quality control measurements

    Quality control (QC) data of radiotherapy linear accelerators, collected by Helsinki University Central Hospital between the years 2000 and 2004, were analysed. The goal was to provide information for the evaluation and elaboration of QC of accelerator outputs and to propose a method for QC data analysis. Short- and long-term drifts in outputs were quantified by fitting empirical mathematical models to the QC measurements. Normally, long-term drifts were well (≤1%) modelled by either a straight line or a single-exponential function. A drift of 2% occurred in 18 ± 12 months. The shortest drift times of only 2-3 months were observed for some new accelerators just after the commissioning but they stabilized during the first 2-3 years. The short-term reproducibility and the long-term stability of local constancy checks, carried out with a sealed plane parallel ion chamber, were also estimated by fitting empirical models to the QC measurements. The reproducibility was 0.2-0.5% depending on the positioning practice of a device. Long-term instabilities of about 0.3%/month were observed for some checking devices. The reproducibility of local absorbed dose measurements was estimated to be about 0.5%. The proposed empirical model fitting of QC data facilitates the recognition of erroneous QC measurements and abnormal output behaviour, caused by malfunctions, offering a tool to improve dose control

  14. Three-dimensional conformal arc radiotherapy using a C-arm linear accelerator with a computed tomography on-rail system for prostate cancer: clinical outcomes

    We report the feasibility and treatment outcomes of image-guided three-dimensional conformal arc radiotherapy (3D-CART) using a C-arm linear accelerator with a computed tomography (CT) on-rail system for localized prostate cancer. Between 2006 and 2011, 282 consecutive patients with localized prostate cancer were treated with in-room CT-guided 3D-CART. Biochemical failure was defined as a rise of at least 2.0 ng/ml beyond the nadir prostate-specific antigen level. Toxicity was scored according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. A total of 261 patients were analyzed retrospectively (median follow-up: 61.6 months). The median prescribed 3D-CART dose was 82 Gy (2 Gy/fraction, dose range: 78–86 Gy), and 193 of the patients additionally received hormonal therapy. The 5-year overall survival rate was 93.9 %. Among low-, intermediate-, and high-risk patients, 5-year rates of freedom from biochemical failure were 100, 91.5 and 90.3 %, respectively. Rates of grade 2–3 late gastrointestinal and genitourinary toxicities were 2.3 and 11.4 %, respectively. No patient experienced late grade 4 or higher toxicity. In-room CT-guided 3D-CART was feasible and effective for localized prostate cancer. Treatment outcomes were comparable to those previously reported for intensity-modulated radiotherapy

  15. In vivo cell kinetic measurements in a randomized trial of continuous hyperfractionated accelerated radiotherapy with or without mitomycin C in head-and-neck cancer

    Purpose: Tumor cell repopulation is still considered to be a major cause of failure in radiotherapy. In this study, we investigated the influence of cell kinetic parameters on the outcome of patients treated in a randomized trial of accelerated fractionation, with or without mitomycin C, vs. conventional fractionation. Methods and Materials: Sixty-two patients were studied using administration of bromodeoxyuridine (BrdUrd), and cell kinetic parameters were measured using flow cytometry. The patients were treated with either 70 Gy for 7 weeks or 55.3 Gy for 17 continuous days (V-CHART) with or without 20 mg/m2 mitomycin C on day 5. Results: The potential doubling time (Tpot) and labeling index (LI) failed to provide any prognostic information with regard to local control or survival. However, the duration of the S phase (Ts) revealed patients whose tumors had a long Ts had significantly worse local control (p = 0.028) and survival (p = 0.034) irrespective of treatment. A similar trend was evident within the different treatment arms particularly associated with overall survival. Conclusions: The Ts values of head-and-neck squamous cell cancers provided prognostic information that predicted clinical outcome irrespective of treatment schedule in this study. This neglected parameter of the Tpot method might provide information related to redistribution of cells during fractionated radiotherapy

  16. Commissioning and quality assurance of the X-ray volume Imaging system of an image-guided radiotherapy capable linear accelerator

    Muralidhar K

    2008-01-01

    Full Text Available An Image-Guided Radiotherapy-capable linear accelerator (Elekta Synergy was installed at our hospital, which is equipped with a kV x-ray volume imaging (XVI system and electronic portal imaging device (iViewGT. The objective of this presentation is to describe the results of commissioning measurements carried out on the XVI facility to verify the manufacturer′s specifications and also to evolve a QA schedule which can be used to test its performance routinely. The QA program consists of a series of tests (safety features, geometric accuracy, and image quality. These tests were found to be useful to assess the performance of the XVI system and also proved that XVI system is very suitable for image-guided high-precision radiation therapy.

  17. Locally advanced head and neck cancer treated with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin. Results from the DAHANCA 18 phase II study

    Bentzen, Jens; Toustrup, Kasper; Eriksen, Jesper Grau; Primdahl, Hanne; Andersen, Lisbeth Juhler; Overgaard, Jens

    2015-01-01

    150 oropharyngeal cancers. Of these, 112 (79%) were p16 pos and 29 (21%) were p16 neg. LRC for the p16 neg oropharyngeal cancers was poorer than for the p16 pos (74% vs. 91%; p = 0.02). Tube feeding during treatment was necessary for 146 (64%) patients. At 12 months this number was reduced to 6......%. CONCLUSION: The treatment was tolerable in this cohort of locally advanced HNSCC patients. Acute and late toxicity was comparable to similar studies of chemoradiotherapy, and the outcome superior to the data reported in the literature. This strongly indicates that RT of a......PURPOSE/OBJECTIVE: A phase II clinical trial evaluating the feasibility and outcome of treating locally advanced head and neck squamous cell carcinoma (HNSCC) with accelerated radiotherapy, the hypoxic modifier nimorazole and weekly cisplatin. MATERIAL AND METHODS: A total of 227 patients with...

  18. Accelerated hyperfractionated intensity-modulated radiotherapy for recurrent/unresectable rectal cancer in patients with previous pelvic irradiation: results of a phase II study

    This study was conducted to investigate the local effects and toxicity of accelerated hyperfractionated intensity-modulated radiotherapy for recurrent/unresectable rectal cancer in patients with previous pelvic irradiation. Twenty-two patients with recurrent/unresectable rectal cancer who previously received pelvic irradiation were enrolled in our single-center trial between January 2007 and August 2012. Reirradiation was scheduled for up to 39 Gy in 30 fractions using intensity-modulated radiotherapy plans. The dose was delivered via a hyperfractionation schedule of 1.3 Gy twice daily. Patient follow-up was performed by clinical examination, CT/MRI, or PET/CT every 3 months for the first 2 years and every 6 months thereafter. Tumor response was evaluated 1 month after reirradiation by CT/MRI based on the RECIST criteria. Adverse events were assessed using the National Cancer Institute (NCI) common toxicity criteria (version 3.0). The median time from the end of the initial radiation therapy to reirradiation was 30 months (range, 18-93 months). Overall local responses were observed in 9 patients (40.9%). None of the patients achieved a complete response (CR), and 9 patients (40.9%) had a partial response (PR). Thirteen patients failed to achieve a clinical response: 12 (54.5%) presented with stable disease (SD) and 1 (4.5%) with progressive disease (PD). Among all the patients who underwent reirradiation, partial or complete symptomatic relief was achieved in 6 patients (27.3%) and 13 patients (59.1%), respectively. Grade 4 acute toxicity and treatment-related deaths were not observed. The following grade 3 acute toxicities were observed: diarrhea (2 patients, 9.1%), cystitis (1 patient, 4.5%), dermatitis (1 patient, 4.5%), and intestinal obstruction (1 patient, 4.5%). Late toxicity was infrequent. Chronic severe diarrhea, small bowel obstruction, and dysuria were observed in 2 (9.1%), 1 (4.5%) and 2 (9.1%) of the patients, respectively. This study showed that

  19. Procedure to measure the neutrons spectrum around a lineal accelerator for radiotherapy; Procedimiento para medir el espectro de los neutrones en torno a un acelerador lineal para radioterapia

    Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Benites R, J. L. [Servicios de Salud de Nayarit, Centro Estatal de Cancerologia, Calzada de la Cruz 116 Sur, 63000 Tepic, Nayarit (Mexico); Salas L, M. A., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Agronomia, Apdo. Postal 336, 98000 Zacatecas (Mexico)

    2013-10-15

    An experimental procedure was developed, by means of Bonner spheres, to measure the neutrons spectrum around Linacs of medical use that only requires of a single shot of the accelerator; to this procedure we denominate Planetary or Isocentric method. One of the problems associated to the neutrons spectrum measurement in a radiotherapy room with lineal accelerator is because inside the room a mixed, intense and pulsed radiation field takes place affecting the detection systems based on active detector; this situation is solved using a passive detector. In the case of the Bonner spheres spectrometer the active detector has been substituted by activation detectors, trace detectors or thermoluminescent dosimeters. This spectrometer uses several spheres that are situated one at a time in the measurement point, this way to have the complete measurements group the accelerator should be operated, under the same conditions, so many times like spheres have the spectrometer, this activity can consume a long time and in occasions due to the work load of Linac to complicate the measurement process too. The procedure developed in this work consisted on to situate all the spectrometer spheres at the same time and to make the reading by means of a single shot, to be able to apply this procedure, is necessary that before the measurements two characteristics are evaluated: the cross-talking of the spheres and the symmetry conditions of the neutron field. This method has been applied to determine the photo-neutrons spectrum produced by a lineal accelerator of medical use Varian ix of 15 MV to 100 cm of the isocenter located to 5 cm of depth of a solid water mannequin of 30 x 30 x 15 cm. The spectrum was used to determine the total flow and the environmental dose equivalent. (Author)

  20. Monte Carlo simulation for the production of neutrons inside the labyrinth function rooms radiotherapy in head rotation of medical linear accelerator use and energy operation

    This work consists of an analysis, through computer simulation using the Monte Carlo method, the production of neutrons generated by the interaction of the beam with useful materials that are heavy in head-accelerated linear medical use. We developed a computer model of the head of the linear accelerator Varian, where there was the ambient dose equivalent due to the neutrons H*(10)n the plane of the patient and the region of the labyrinth bunker for several angles of operating at energies of 10, 15, 18 MV. It was found that production of neutrons in the plane of the patient has direct dependency with increasing beam energy useful, since the labyrinth it appears that besides energy the operating angle also has a direct influence on the production of neutrons in the region of the labyrinth, consequently the door. Therefore, a survey of H*(10)n at various angles with different operating ranges of energy contributes to better planning studies concerning shielding doors in rooms radiotherapy. (author)

  1. Intraoperative radiotherapy

    The potential benefit of intraoperative radiotherapy (IORT) was originally recognized years ago and has recently attracted renewed interest. Modern radiotherapeutic approaches may be more successful as a result of technical innovation, particularly in the use of electron beam accelerators. Preliminary studies, mainly uncontrolled and nonrandomized, have assessed the role of IORT for treatment of a variety of deep seated abdominal, retroperitoneal, and pelvic cancers. The results of some studies show much promise, but prospective trials are needed to scientifically validate these favorable initial observations. (Auth.)

  2. Accelerated Hyperfractionated Radiotherapy for Cervical Cancer: Multi-Institutional Prospective Study of Forum for Nuclear Cooperation in Asia Among Eight Asian Countries

    Purpose: To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. Methods and Materials: A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with the patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Results: The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors ≥6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. Conclusion: The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available

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

    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

  4. Predicting the Effect of Accelerated Fractionation in Postoperative Radiotherapy for Head and Neck Cancer Based on Molecular Marker Profiles: Data From a Randomized Clinical Trial

    Purpose: To determine the prognostic and predictive values of molecular marker expression profiles based on data from a randomized clinical trial of postoperative conventional fractionation (p-CF) therapy versus 7-day-per-week postoperative continuous accelerated irradiation (p-CAIR) therapy for squamous cell cancer of the head and neck. Methods and Materials: Tumor samples from 148 patients (72 p-CF and 76 p-CAIR patients) were available for molecular studies. Immunohistochemistry was used to assess levels of EGFR, nm23, Ki-67, p-53, and cyclin D1 expression. To evaluate the effect of fractionation relative to the expression profiles, data for locoregional tumor control (LRC) were analyzed using the Cox proportional hazard regression model. Survival curves were compared using the Cox f test. Results: Patients who had tumors with low Ki-67, low p-53, and high EGFR expression levels and oral cavity/oropharyngeal primary cancer sites tended to benefit from p-CAIR. A joint score for the gain in LRC from p-CAIR based of these features was used to separate the patients into two groups: those who benefited significantly from p-CAIR with respect to LRC (n = 49 patients; 5-year LRC of 28% vs. 68%; p = 0.01) and those who did not benefit from p-CAIR (n = 99 patients; 5-year LRC of 72% vs. 66%; p = 0.38). The nm23 expression level appeared useful as a prognostic factor but not as a predictor of fractionation effect. Conclusions: These results support the studies that demonstrate the potential of molecular profiles to predict the benefit from accelerated radiotherapy. The molecular profile that favored accelerated treatment (low Ki-67, low p-53, and high EGFR expression) was in a good accordance with results provided by other investigators. Combining individual predictors in a joint score may improve their predictive potential.

  5. Poster — Thur Eve — 28: Enabling trajectory-based radiotherapy on a TrueBeam accelerator with the Eclipse treatment planning system

    Mullins, J; Asiev, K; DeBlois, F; Morcos, M; Seuntjens, J; Syme, A [Department of Oncology, McGill University (Canada)

    2014-08-15

    The TrueBeam linear accelerator platform has a developer's mode which permits the user dynamic control over many of the machine's mechanical and radiation systems. Using this research tool, synchronous couch and gantry motion can be programmed to simulate isocentric treatment with a shortened SAD, with benefits such as smaller projected MLC leaf widths and an increased dose rate. In this work, water tank measurements were used to commission a virtual linear accelerator with an 85 cm SAD in Eclipse, from which several arc-based radiotherapy treatments were generated, including an inverse optimized VMAT delivery. For each plan, the pertinent treatment delivery information was extracted from control points specified in the Eclipse-exported DICOM files using the pydicom package in Python, allowing construction of an XML control file. The dimensions of the jaws and MLC positions, defined for an 85 cm SAD in Eclipse, were scaled for delivery on a conventional SAD linear accelerator, and translational couch motion was added as a function of gantry angle to simulate delivery at 85 cm SAD. Ionization chamber and Gafchromic film measurements were used to compare the radiation delivery to dose calculations in Eclipse. With the exception of the VMAT delivery, ionization chamber measurements agreed within 3.3% of the Eclipse calculations. For the VMAT delivery, the ionization chamber was located in an inhomogeneous region, but gamma evaluation of the Gafchromic film plane resulted in a 94.5% passing rate using criteria of 3 mm/3%. The results indicate that Eclipse calculation infrastructure can be used.

  6. Poster — Thur Eve — 28: Enabling trajectory-based radiotherapy on a TrueBeam accelerator with the Eclipse treatment planning system

    The TrueBeam linear accelerator platform has a developer's mode which permits the user dynamic control over many of the machine's mechanical and radiation systems. Using this research tool, synchronous couch and gantry motion can be programmed to simulate isocentric treatment with a shortened SAD, with benefits such as smaller projected MLC leaf widths and an increased dose rate. In this work, water tank measurements were used to commission a virtual linear accelerator with an 85 cm SAD in Eclipse, from which several arc-based radiotherapy treatments were generated, including an inverse optimized VMAT delivery. For each plan, the pertinent treatment delivery information was extracted from control points specified in the Eclipse-exported DICOM files using the pydicom package in Python, allowing construction of an XML control file. The dimensions of the jaws and MLC positions, defined for an 85 cm SAD in Eclipse, were scaled for delivery on a conventional SAD linear accelerator, and translational couch motion was added as a function of gantry angle to simulate delivery at 85 cm SAD. Ionization chamber and Gafchromic film measurements were used to compare the radiation delivery to dose calculations in Eclipse. With the exception of the VMAT delivery, ionization chamber measurements agreed within 3.3% of the Eclipse calculations. For the VMAT delivery, the ionization chamber was located in an inhomogeneous region, but gamma evaluation of the Gafchromic film plane resulted in a 94.5% passing rate using criteria of 3 mm/3%. The results indicate that Eclipse calculation infrastructure can be used

  7. A Phase I Study of Chemoradiotherapy With Use of Involved-Field Conformal Radiotherapy and Accelerated Hyperfractionation for Stage III Non-Small Cell Lung Cancer: WJTOG 3305

    Purpose: A Phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non–small-cell lung cancer was conducted. Methods and Materials: Patients with unresectable Stage III non–small-cell lung cancer were treated intravenously with carboplatin (area under the concentration curve 2) and paclitaxel (40 mg/m2) on Days 1, 8, 15, and 22 with concurrent twice-daily thoracic radiotherapy (1.5 Gy per fraction) beginning on Day 1 followed by two cycles of consolidation chemotherapy using carboplatin (area under the concentration curve 5) and paclitaxel (200 mg/m2). Total doses were 54 Gy in 36 fractions, 60 Gy in 40 fractions, 66 Gy in 44 fractions, and 72 Gy in 48 fractions at Levels 1 to 4. The dose-limiting toxicity, defined as Grade ≥4 esophagitis and neutropenic fever and Grade ≥3 other nonhematologic toxicities, was monitored for 90 days. Results: Of 26 patients enrolled, 22 patients were assessable for response and toxicity. When 4 patients entered Level 4, enrollment was closed to avoid severe late toxicities. Dose-limiting toxicities occurred in 3 patients. They were Grade 3 neuropathy at Level 1 and Level 3 and Grade 3 infection at Level 1. However, the maximum tolerated dose was not reached. The median survival time was 28.6 months for all patients. Conclusions: The maximum tolerated dose was not reached, although the dose of radiation was escalated to 72 Gy in 48 fractions. However, a dose of 66 Gy in 44 fractions was adopted for this study because late toxicity data were insufficient.

  8. A Phase I Study of Chemoradiotherapy With Use of Involved-Field Conformal Radiotherapy and Accelerated Hyperfractionation for Stage III Non-Small Cell Lung Cancer: WJTOG 3305

    Tada, Takuhito, E-mail: tada@msic.med.osaka-cu.ac.jp [Department of Radiology, Osaka City University Graduate School of Medicine, Osaka (Japan); Department of Radiology, Izumi Municipal Hospital, Izumi (Japan); Chiba, Yasutaka [Department of Environmental Medicine and Behavioural Science, Kinki University Faculty of Medicine, Osaka-sayama (Japan); Tsujino, Kayoko [Department of Radiation Oncology, Hyogo Cancer Center, Akashi (Japan); Fukuda, Haruyuki [Department of Radiology, Osaka Prefectural Medical Center for Respiratory and Allergic Diseases, Habikino (Japan); Nishimura, Yasumasa [Department of Radiation Oncology, Kinki University Faculty of Medicine, Osaka-sayama (Japan); Kokubo, Masaki [Division of Radiation Oncology, Institute of Biomedical Research and Innovation, Kobe (Japan); Negoro, Shunichi [Department of Medical Oncology, Hyogo Cancer Center, Akashi (Japan); Kudoh, Shinzoh [Department of Respiratory Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Fukuoka, Masahiro [Department of Medical Oncology, Izumi Municipal Hospital, Izumi (Japan); Nakagawa, Kazuhiko [Department of Medical Oncology, Kinki University Faculty of Medicine, Osaka-sayama (Japan); Nakanishi, Yoichi [Research Institute for Disease of the Chest, Graduate School of Medical Science, Kyusyu University, Fukuoka (Japan)

    2012-05-01

    Purpose: A Phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non-small-cell lung cancer was conducted. Methods and Materials: Patients with unresectable Stage III non-small-cell lung cancer were treated intravenously with carboplatin (area under the concentration curve 2) and paclitaxel (40 mg/m{sup 2}) on Days 1, 8, 15, and 22 with concurrent twice-daily thoracic radiotherapy (1.5 Gy per fraction) beginning on Day 1 followed by two cycles of consolidation chemotherapy using carboplatin (area under the concentration curve 5) and paclitaxel (200 mg/m{sup 2}). Total doses were 54 Gy in 36 fractions, 60 Gy in 40 fractions, 66 Gy in 44 fractions, and 72 Gy in 48 fractions at Levels 1 to 4. The dose-limiting toxicity, defined as Grade {>=}4 esophagitis and neutropenic fever and Grade {>=}3 other nonhematologic toxicities, was monitored for 90 days. Results: Of 26 patients enrolled, 22 patients were assessable for response and toxicity. When 4 patients entered Level 4, enrollment was closed to avoid severe late toxicities. Dose-limiting toxicities occurred in 3 patients. They were Grade 3 neuropathy at Level 1 and Level 3 and Grade 3 infection at Level 1. However, the maximum tolerated dose was not reached. The median survival time was 28.6 months for all patients. Conclusions: The maximum tolerated dose was not reached, although the dose of radiation was escalated to 72 Gy in 48 fractions. However, a dose of 66 Gy in 44 fractions was adopted for this study because late toxicity data were insufficient.

  9. NSCLC: primary tumor size - radiation dose-related accelerated, twice daily radiotherapy by target splitting, preceded by 2 cycles of chemotherapy. First results of a prospective study

    Ensuing a phase I trial of accelerated, twice daily high dose radiotherapy showing good tolerability, a prospective study relating primary tumor size with radiation dose in non-operated patients with non-small cell lung cancer (NSCLC) was started. From 01/2004 until 12/2006 79 patients with 81 histologically/cytologically proven NSCLC tumors were treated, representing 94% of all referred non-operated NSCLC patients in stage Mo, malignant pleural effusions excluded. For the majority of patients the conformal target splitting technique has been employed. The target is split into a cranial and a caudal part; beam arrangements in the two parts are completely independent. In order to reduce internal margins slow planning CTs (4 sec./slice) were used, patients freely breathing, 7 mm margins from gross tumor volume to planning target volume. We formed 4 groups with primary tumor sizes (mean number of 3 perpendicular diameters) 6,0 cm (11/41/22/7 patients, respectively); tumor doses of 73,8, 79,2, 84,6 and 90,0 Gy (ICRU) were applied to the primary tumors of the patients in the respective groups. Single dose 1,8 Gy; twice daily, interval 11 h; 5 days/week; duration 33 days median (range 29-42). Macroscopically involved nodes 61,2 Gy median (range 54,0-75,6 Gy), nodes electively 45,0 Gy (to volume about 6 cm cranial to apparently involved nodes). In 62 patients chemotherapy before radiotherapy was given, 2 cycles median, generally a cisplatin or carboplatin containing doublet; no concurrent chemotherapy. Median follow-up of all patients 16,7 months, of patients alive 19,3 months. Until now 10 local failures (0/11, 3/41, 5/22, 2/7 in the respective groups) and 2 regional failures occured, resulting in an actuarial local and regional tumor control of 80,1% and 96% at 2 years, respectively. Local failures relate to the primary tumor site, regional failures to the regional node sites. Overall actuarial 1-, 2-year survival rate for all patients: 76%, 56%, respectively, median 26

  10. Tracking the dynamic seroma cavity using fiducial markers in patients treated with accelerated partial breast irradiation using 3D conformal radiotherapy

    Yue, Ning J.; Haffty, Bruce G.; Goyal, Sharad [Department of Radiation Oncology, Cancer Institute of New Jersey, UMDNJ/Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903 (United States); Kearney, Thomas; Kirstein, Laurie [Division of Surgical Oncology, Cancer Institute of New Jersey, UMDNJ/Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903 (United States); Chen Sining [Department of Biostatistics, Cancer Institute of New Jersey, UMDNJ/School of Public Health, New Brunswick, NJ 08901 (United States)

    2013-02-15

    Purpose: The purpose of the present study was to perform an analysis of the changes in the dynamic seroma cavity based on fiducial markers in early stage breast cancer patients treated with accelerated partial breast irradiation (APBI) using three-dimensional conformal external beam radiotherapy (3D-CRT). Methods: A prospective, single arm trial was designed to investigate the utility of gold fiducial markers in image guided APBI using 3D-CRT. At the time of lumpectomy, four to six suture-type gold fiducial markers were sutured to the walls of the cavity. Patients were treated with a fractionation scheme consisting of 15 fractions with a fractional dose of 333 cGy. Treatment design and planning followed NSABP/RTOG B-39 guidelines. During radiation treatment, daily kV imaging was performed and the markers were localized and tracked. The change in distance between fiducial markers was analyzed based on the planning CT and daily kV images. Results: Thirty-four patients were simulated at an average of 28 days after surgery, and started the treatment on an average of 39 days after surgery. The average intermarker distance (AiMD) between fiducial markers was strongly correlated to seroma volume. The average reduction in AiMD was 19.1% (range 0.0%-41.4%) and 10.8% (range 0.0%-35.6%) for all the patients between simulation and completion of radiotherapy, and between simulation and beginning of radiotherapy, respectively. The change of AiMD fits an exponential function with a half-life of seroma shrinkage. The average half-life for seroma shrinkage was 15 days. After accounting for the reduction which started to occur after surgery through CT simulation and treatment, radiation was found to have minimal impact on the distance change over the treatment course. Conclusions: Using the marker distance change as a surrogate for seroma volume, it appears that the seroma cavity experiences an exponential reduction in size. The change in seroma size has implications in the size of

  11. Neurocognitive outcome in brain metastases patients treated with accelerated-fractionation vs. accelerated-hyperfractionated radiotherapy: an analysis from Radiation Therapy Oncology Group Study 91-04

    Purpose: To evaluate neurocognitive outcome as measured by the Mini-Mental Status Examination (MMSE) among patients with unresectable brain metastases randomly assigned to accelerated fractionation (AF) vs. accelerated hyperfractionated (AH) whole-brain radiation therapy (WBRT). Methods and Materials: The Radiation Therapy Oncology Group (RTOG) accrued 445 patients with unresectable brain metastases to a Phase III comparison of AH (1.6 Gy b.i.d. to 54.4 Gy) vs. AF (3 Gy q.d. to 30 Gy). All had a KPS of ≥ 70 and a neurologic function status of 0-2. Three hundred fifty-nine patients had MMSEs performed and were eligible for this analysis. Changes in the MMSE were analyzed according to criteria previously defined in the literature. Results: The median survival was 4.5 months for both arms. The average change in MMSE at 2 and 3 months was a drop of 1.4 and 1.1, respectively, in the AF arm as compared to a drop of 0.7 and 1.3, respectively, in the AH arm (p=NS). Overall, 91 patients at 2 months and 23 patients at 3 months had both follow-up MMSE and computed tomography/magnetic resonance imaging documentation of the status of their brain metastases. When an analysis was performed taking into account control of brain metastases, a significant effect on MMSE was observed with time and associated proportional increase in uncontrolled brain metastases. At 2 months, the average change in MMSE score was a drop of 0.6 for those whose brain metastases were radiologically controlled as compared to a drop of 1.9 for those with uncontrolled brain metastases (p=0.47). At 3 months, the average change in MMSE score was a drop of 0.5 for those whose brain metastases were radiologically controlled as compared to a drop of 6.3 for those with uncontrolled brain metastases (p=0.02). Conclusion: Use of AH as compared to AF-WBRT was not associated with a significant difference in neurocognitive function as measured by MMSE in this patient population with unresectable brain metastases and

  12. Determination of the neutron spectra in the treatment room of a linear accelerator for radiotherapy; Determinacion de los espectros de neutrones en la sala de tratamiento de un acelerador lineal para radioterapia

    Vega C, H.R. [Universidad Autonoma de Zacatecas, Cuerpo Academico de Radiobiologia, A.P. 336, 98000 Zacatecas (Mexico); Barquero, R. [Hospital Universitario Rio Hortega, Valladolid (Spain); Mendez, R.; Iniguez, M.P. [Depto. de Fisica Teorica, Atomica, Molecular y Nuclear, Universidad de Valladolid, 47011 Valladolid (Spain)

    2003-07-01

    By means of a series of measures and Monte Carlo calculations the dosimetric characteristics of the photoneutrons have been determined that take place in volume to a linear accelerator of radiotherapy of 18 MV, LINAC, mark Siemens Mevatron model. The measures were carried out with thermoluminescent dosemeters TLD 600 and TLD 700 that were naked exposed and confined with cover of Cd and Sn, inside a sphere of paraffin and inside spheres Bonner. (Author)

  13. Clinical Experiences With Onboard Imager KV Images for Linear Accelerator-Based Stereotactic Radiosurgery and Radiotherapy Setup

    Purpose: To report our clinical experiences with on-board imager (OBI) kV image verification for cranial stereotactic radiosurgery (SRS) and radiotherapy (SRT) treatments. Methods and Materials: Between January 2007 and May 2008, 42 patients (57 lesions) were treated with SRS with head frame immobilization and 13 patients (14 lesions) were treated with SRT with face mask immobilization at our institution. No margin was added to the gross tumor for SRS patients, and a 3-mm three-dimensional margin was added to the gross tumor to create the planning target volume for SRT patients. After localizing the patient with stereotactic target positioner (TaPo), orthogonal kV images using OBI were taken and fused to planning digital reconstructed radiographs. Suggested couch shifts in vertical, longitudinal, and lateral directions were recorded. kV images were also taken immediately after treatment for 21 SRS patients and on a weekly basis for 6 SRT patients to assess any intrafraction changes. Results: For SRS patients, 57 pretreatment kV images were evaluated and the suggested shifts were all within 1 mm in any direction (i.e., within the accuracy of image fusion). For SRT patients, the suggested shifts were out of the 3-mm tolerance for 31 of 309 setups. Intrafraction motions were detected in 3 SRT patients. Conclusions: kV imaging provided a useful tool for SRS or SRT setups. For SRS setup with head frame, it provides radiographic confirmation of localization using the stereotactic target positioner. For SRT with mask, a 3-mm margin is adequate and feasible for routine setup when TaPo is combined with kV imaging

  14. Concurrent hyperfractionated accelerated radiotherapy with 5-FU and once weekly cisplatin in locally advanced head and neck cancer. The 10-year results of a prospective phase II trial

    In this study, the acute toxicity and long-term outcome of a hyperfractionated accelerated chemoradiation regimen with cisplatin/5-fluorouracil (5-FU) in patients with locally advanced squamous cell carcinomas of head and neck were evaluated. From 2000-2002, 38 patients with stage III (5.3 %) and stage IV (94.7 %) head and neck cancer were enrolled in a phase II study. Patients received hyperfractionated-accelerated radiotherapy with 72 Gy in 15 fractions of 2 Gy followed by 1.4 Gy twice daily with concurrent, continuous infusion 5-FU of 600 mg/m2 on days 1-5 and 6 cycles of weekly cisplatin (30 mg/m2). Acute toxicities (CTCAEv2.0), locoregional control (LRC), metastases-free (MFS), and overall survival (OS) were analyzed and exploratively compared with the ARO 95-06 trial. Median follow-up was 11.4 years (95 % CI 8.6-14.2) and mean dose 71.6 Gy. Of the patients, 82 % had 6 (n = 15) or 5 (n = 16) cycles of cisplatin, 5 and 2 patients received 4 and 3 cycles, respectively. Grade 3 anemia, leukopenia, and thrombocytopenia were observed in 15.8, 15.8, and 2.6 %, respectively. Grade 3 mucositis in 50 %, grade 3 and 4 dysphagia in 55 and 13 %. The 2-, 5-, and 10-year LRC was 65, 53.6, and 48.2 %, the MFS was 77.5, 66.7, and 57.2 % and the OS 59.6, 29.2, and 15 %, respectively. Chemoradiation with 5-FU and cisplatin seems feasible and superior in terms of LRC and OS to the ARO 95-06C-HART arm at 2 years. However, this did not persist at the 5- and 10-year follow-ups. (orig.)

  15. Be aware of neutrons outside short mazes from 10-mv linear accelerators x-rays in radiotherapy facilities

    During the radiation survey of a reinstalled 10-MV linear accelerator in an old radiation treatment facility, high dose rates of neutrons were observed. The area outside the maze entrance is used as a waiting room where patients, their relatives and staff other than those involved in the actual treatment can freely pass. High fluence rates of neutrons would cause an unnecessary high effective dose to the staff working in the vicinity of such a system, and it can be several orders higher than the doses received due to X-rays at the same location. However, the common knowledge appears to have been that the effect of neutrons at 10-MV X-ray linear accelerator facilities is negligible and shielding calculations models seldom mention neutrons for this operating energy level. Although data are scarce, reports regarding this phenomenon are now emerging. For the future, it is advocated that contributions from neutrons are considered already during the planning stage of new or modified facilities aimed for 10 MV and that estimated dose levels are verified. (authors)

  16. Determination of attenuation of X-radiations in some selected materials using the linear accelerator for radiotherapy

    Radiation travelling through a medium could be attenuated in different ways depending on the type of medium. The research was done on the above basis and was carried out at the Medical Physics department of the National Hospital Abuja using the linear accelerator and an ionization chamber (farmer-type) which served as a radiation detector. The materials used for this research were: the Perspex, concrete, moulded clay (mud), wood, jean material, ordinary material (clothe), cardboard paper, ordinary paper and foam of which each was of (12 x 12 x 1)cm3 except for Perspex which was of (30 x 30 x 1)cm3. They were all beamed at one after the other using energy of 6MV photons from the linear accelerator. The chamber detected the radiation passing through each material and sent it (radiation) in minute current signals to an electrometer which read the signals in milligray. The results obtained indicated that Perspex would best attenuate radiation, but considering its cost, concrete is considered cheaper and next to Perspex from the results and would play a better role.

  17. Calculation of the structural shielding of the radiotherapy treatment room equipped with a linear accelerator type Tomo therapy Hi-Art in the Oncology Center of Chihuahua, Mexico

    The helicoid tomo therapy is an external radiotherapy system of modulated intensity, guided by image, in which the radiation is imparted to the patient using a narrow radiation beam in helicoid form, in a similar way to the scanning process with a computerized tomography. The tomo therapy equipment (Tomo Therapy Hi-Art) consists in an electrons linear accelerator with acceleration voltages of 6 MV for treatment and 3.5 MV for image, coupled to a ring that turn around the patient as this is transferred through this ring in perpendicular sense to the radiation beam. The radiation beam is narrow because has the maximum size of 5 x 40 cm2 in the isocenter. The intensity modulation of the beam is carried out with a binary dynamic collimator of 64 crisscross sheets, and the guide by image though a system of megavoltage computerized tomography. Opposed to the radiation beam, also coupled to the rotational ring, a group of lead plates exists with a total thickness of 13 cm that acts as barrier of the primary radiation beam. The special configuration of the tomography equipment makes to have the following characteristics: 1) the presence of the lead barrier of the equipment reduces the intensity of the primary beam that reaches the bunker walls in considerable way, 2) the disperse and leakage radiations are increased with regard to a conventional accelerator due to the increase in the necessary irradiation time to produce modulated intensity fields by means of the narrow radiation beam. These special characteristics of the tomo therapy equipment make that particularities exist in the application of the formulations for structural shielding calculations that appears in the NCRP reports 49, NCRP 151 and IAEA-SRS-47. For this reason, several researches have development analytic models based on geometric considerations of continuous rotation of the equipment ring to determine the shielding requirements for the primary beam, the dispersed and leakage radiation in tomo therapy

  18. SU-E-T-190: First Integration of Steriotactic Radiotherapy Planning System Iplan with Elekta Linear Accelerator

    Purpose: For the first time in the world, BrainLAB has integrated its iPlan treatment planning system for clinical use with Elekta linear accelerator (Axesse with a Beam Modulator). The purpose of this study was to compare the calculated and measured doses with different chambers to establish the calculation accuracy of iPlan system. Methods: The iPlan has both Pencil beam (PB) and Monte Carlo (MC) calculation algorithms. Beam data include depth doses, profiles and output measurements for different field sizes. Collected data was verified by vendor and beam modelling was done. Further QA tests were carried out in our clinic. Dose calculation accuracy verified point, volumetric dose measurement using ion chambers of different volumes (0.01cc and 0.125cc). Planner dose verification was done using diode array. Plans were generated in iPlan and irradiated in Elekta Axesse linear accelerator. Results: Dose calculation accuracies verified using ion chamber for 6 and 10 MV beam were 3.5+/-0.33(PB), 1.7%+/-0.7(MC) and 3.9%+/-0.6(PB), 3.4%+/-0.6(MC) respectively. Using a pin point chamber, dose calculation accuracy for 6MV and 10MV was 3.8%+/-0.06(PB), 1.21%+/-0.2(MC) and 4.2%+/-0.6(PB), 3.1%+/-0.7(MC) respectively. The calculated planar dose distribution for 10.4×10.4 cm2 was verified using a diode array and the gamma analysis for 2%-2mm criteria yielded pass rates of 88 %(PB) and 98.8%(MC) respectively. 3mm-3% yields 100% passing for both MC and PB algorithm. Conclusion: Dose calculation accuracy was found to be within acceptable limits for MC for 6MV beam. PB for both beams and MC for 10 MV beam were found to be outside acceptable limits. The output measurements were done twice for conformation. The lower gamma matching was attributed to meager number of measured profiles (only two profiles for PB) and coarse measurement resolution for diagonal profile measurement (5mm). Based on these measurements we concluded that 6 MV MC algorithm is suitable for patient treatment

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

    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

  20. Estimation of absorbed dose in clinical radiotherapy linear accelerator beams: effect of ion chamber calibration and long-term stability

    The measured dose in water at reference point in phantom is a primary parameter for planning the treatment monitor units (MU); both in conventional and intensity modulated/image guided treatments. Traceability of dose accuracy therefore still depends mainly on the calibration factor of the ion chamber/dosimeter provided by the accredited Secondary Standard Dosimetry Laboratories (SSDLs), under International Atomic Energy Agency (IAEA) network of laboratories. The data related to Nd,water calibrations, thermoluminescent dosimetry (TLD) postal dose validation, inter-comparison of different dosimeter/electrometers, and validity of Nd,water calibrations obtained from different calibration laboratories were analyzed to find out the extent of accuracy achievable. Nd,w factors in Gray/Coulomb calibrated at IBA, GmBH, Germany showed a mean variation of about 0.2% increase per year in three Farmer chambers, in three subsequent calibrations. Another ion chamber calibrated in different accredited laboratory (PTW, Germany) showed consistent Nd,w for 9 years period. The Strontium-90 beta check source response indicated long-term stability of the ion chambers within 1% for three chambers. Results of IAEA postal TL 'dose intercomparison' for three photon beams, 6 MV (two) and 15 MV (one), agreed well within our reported doses, with mean deviation of 0.03% (SD 0.87%) (n = 9). All the chamber/electrometer calibrated by a single SSDL realized absorbed doses in water within 0.13% standard deviations. However, about 1-2% differences in absorbed dose estimates observed when dosimeters calibrated from different calibration laboratories are compared in solid phantoms. Our data therefore imply that the dosimetry level maintained for clinical use of linear accelerator photon beams are within recommended levels of accuracy and uncertainities are within reported values. (author)

  1. Main of probabilistic safety assessment (PSA) of the radiotherapy treatment process with a linear accelerator for medical purposes (linac)

    The radiation safety assessments traditionally have been based on analyzing the lessons you learn of new events that are becoming known. Although these methods are very valuable, their main limitation is that only cover known events and leave without consider other possible failures that have occurred or have not been published, This does not mean they can not occur. Other tools to analyze prospectively the safety, among which found Probabilistic Safety Assessment (PSA). This paper summarizes the project of American Forum of agencies radiological and nuclear regulators aimed at applying the methods of APS treatment process with a linear accelerator. We defined as unintended consequences accidental exposures both single patient and multiple patients. FMEA methodology was used to define events initiators of accidents and methods of event trees and trees failure to identify the accident sequences that may occur. A Once quantified the frequency of occurrence of accidental sequences Analyses of importance in determining the most recent events significant from the point of view of safety. We identified 158 of equipment failure modes and 295 errors human if they occurred would have the potential to cause the accidental exposures defined. We studied 118 of initiating events accident and 120 barriers. We studied 434 accident sequences. The accidental exposure of a single patient were 40 times likely that multiple patients. 100% of the total frequency of accidental exposures on a single patient is caused by human errors . 8% of the total frequency of accidental exposures on multiple patients initiating events may occur by equipment failure (Computerized tomography, treatment planning system, throttle linear) and 92% by human error. As part of the and recommendations of the study presents the events that are more contribution on the reduction of risk of accidental exposure. (author)

  2. Cost minimization analysis at the Hospital Mexico in the Caja Costarricense de Seguro Social for the accommodation of patients with radiotherapy with linear accelerator: shelter vs transfers

    Patients with oncological pathology have attended daily in sessions for several weeks in the linear accelerator radiation therapy. Persons subject to this intervention have moved to the Hospital Mexico of the social security of Costa Rica, place that centralizes this treatment. The Caja Costarricense de Seguro Social (CCSS) has considered two options depending on the place of origin of users: bear the costs of commuting from the area of habitual residence, or place them temporarily in a shelter provided by the institution; the CCSS has chosen the first alternative. This research has consisted of a cost-minimization analysis between these two alternatives. The study population are patients with oncological pathology attending sessions of radiotherapy with linear accelerator at the Hospital Mexico in the first half of 2009 using ambulances of Cruz Roja Costarricense. The size of the study population is 107 persons, the total number of transferred recorded in the Fondo Rotatorio de Operaciones of Hospital Mexico is 998. Patients came from five regions and twenty areas of health according to the geographical division of the CCSS. The variables included have been: cost per day by way of transfer, which involves the distance to the radiotherapy center of Hospital Mexico and the cost of the rate at Cruz Roja ambulance per Km (326.86 colons, according to the agreement CCSS-Cruz Roja in June 2009) estimated daily cost of lodging in a shelter, and the reason daily cost of relocation / daily cost of shelter. The cost of shelter includes food and were used data from the company International Medical Suppliers S. A. as a basis for estimating the daily cost, the price fixed by the company was 65 dollars a day, and the conversion into colons exchange rate as established by the Banco Central de Costa Rica; dated April 30, 2010, the amount has been 33.542.60 colons. The reason for each area of health was given by the ratio of the average daily cost in colons by way of ambulance of

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

    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.)

  4. Induction Chemotherapy and Continuous Hyperfractionated Accelerated Radiotherapy (CHART) for Patients With Locally Advanced Inoperable Non-Small-Cell Lung Cancer: The MRC INCH Randomized Trial

    Purpose: Recent clinical trials and meta-analyses have shown that both CHART (continuous hyperfractionated accelerated radiation therapy) and induction chemotherapy offer a survival advantage over conventional radical radiotherapy for patients with inoperable non-small cell-lung cancer (NSCLC). This multicenter randomized controlled trial (INCH) was set up to assess the value of giving induction chemotherapy before CHART. Methods and Materials: Patients with histologically confirmed, inoperable, Stage I-III NSCLC were randomized to induction chemotherapy (ICT) (three cycles of cisplatin-based chemotherapy followed by CHART) or CHART alone. Results: Forty-six patients were randomized (23 in each treatment arm) from 9 UK centers. As a result of poor accrual, the trial was closed in December 2007. Twenty-eight patients were male, 28 had squamous cell histology, 34 were Stage IIIA or IIIB, and all baseline characteristics were well balanced between the two treatment arms. Seventeen (74%) of the 23 ICT patients completed the three cycles of chemotherapy. All 42 (22 CHART + 20 ICT) patients who received CHART completed the prescribed treatment. Median survival was 17 months in the CHART arm and 25 months in the ICT arm (hazard ratio of 0.60 [95% CI 0.31-1.16], p = 0.127). Grade 3 or 4 adverse events (mainly fatigue, dysphagia, breathlessness, and anorexia) were reported for 13 (57%) CHART and 13 (65%) ICT patients. Conclusions: This small randomized trial indicates that ICT followed by CHART is feasible and well tolerated. Despite closing early because of poor accrual, and so failing to show clear evidence of a survival benefit for the additional chemotherapy, the results suggest that CHART, and ICT before CHART, remain important options for the treatment of inoperable NSCLC and deserve further study.

  5. Dose volume histogram analysis of normal structures associated with accelerated partial breast irradiation delivered by high dose rate brachytherapy and comparison with whole breast external beam radiotherapy fields

    Mutyala Subhakar

    2008-11-01

    Full Text Available Abstract Purpose To assess the radiation dose delivered to the heart and ipsilateral lung during accelerated partial breast brachytherapy using a MammoSite™ applicator and compare to those produced by whole breast external beam radiotherapy (WBRT. Materials and methods Dosimetric analysis was conducted on patients receiving MammoSite breast brachytherapy following conservative surgery for invasive ductal carcinoma. Cardiac dose was evaluated for patients with left breast tumors with a CT scan encompassing the entire heart. Lung dose was evaluated for patients in whom the entire lung was scanned. The prescription dose of 3400 cGy was 1 cm from the balloon surface. MammoSite dosimetry was compared to simulated WBRT fields with and without radiobiological correction for the effects of dose and fractionation. Dose parameters such as the volume of the structure receiving 10 Gy or more (V10 and the dose received by 20 cc of the structure (D20, were calculated as well as the maximum and mean doses received. Results Fifteen patients were studied, five had complete lung data and six had left-sided tumors with complete cardiac data. Ipsilateral lung volumes ranged from 925–1380 cc. Cardiac volumes ranged from 337–551 cc. MammoSite resulted in a significantly lower percentage lung V30 and lung and cardiac V20 than the WBRT fields, with and without radiobiological correction. Conclusion This study gives low values for incidental radiation received by the heart and ipsilateral lung using the MammoSite applicator. The volume of heart and lung irradiated to clinically significant levels was significantly lower with the MammoSite applicator than using simulated WBRT fields of the same CT data sets. Trial registration Dana Farber Trial Registry number 03-179

  6. Long-term results of low dose daily cisplatin chemotherapy used concurrently with modestly accelerated radiotherapy in locally advanced squamous cell carcinomas of the head neck cancer region

    Pramod Kumar Gupta

    2014-01-01

    Full Text Available Introduction: Concurrent single agent cisplatin (CDDP with radiotherapy (RT improves outcomes in locally advanced squamous cell carcinomas of the head neck (LA-SCCHN. CDDP at 100 mg/m 2 at 3 weekly intervals raise compliance, hospitalization, and supportive care issues. Low dose daily CDDP was delivered with RT to evaluate its compliance, long-term safety and efficacy. Patients and Methods: During the period of month between November 2005 and May 2007, 52 patients of stage III/IV LA-SCCHN were given with conventional RT in a phased manner (dose-70 Gy/35 fractions/6 weeks along with daily CDDP (6 mg/m 2 ; capped 10 mg-30 cycles over 6 weeks. No hospitalization or antiemetic cover was planned. Compliance, acute and late toxicity were recorded as per Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer grading system and survival outcomes were evaluated. Results : The median follow-up was 63 months. 43 (83% cases complied with RT schedule and >28 cycles of CDDP was administered in 38 (73% cases. Confluent mucositis was seen in 65%, Grade III/IV dysphagia in 67%; 77% required enteral feed and hospitalization in 15%. There were four treatment related deaths. At 5 years, the loco-regional control was 25% (median-11 months and the overall survival was 31% (median-11 months. The 5 years actuarial rates of late Grade III/IV toxicity was 24%. Late swallowing difficulty/aspiration were seen in 17%; xerostomia-40%; ototoxicity-6%; nephrotoxicity-4%; and no second malignancy. Conclusion: Low dose cisplatin with moderately accelerated RT schedule appears feasible and logistically suitable "out-patient" option without increasing long-term toxicity in LA-SCCHN cancer region.

  7. Elective lymph node irradiation late course accelerated hyper-fractionated radiotherapy plus concurrent cisplatin-based chemotherapy for esophageal squamous cell carcinoma: a phase II study

    In this phase II study, we evaluated the efficacy, toxicity, and patterns of failure of elective lymph node irradiation (ENI) late course accelerated hyper-fractionated radiotherapy (LCAHRT) concurrently with cisplatin-based chemotherapy (CHT) for esophageal squamous cell carcinoma (ESCC). Patients with clinical stage II-IVa (T1-4N0-1M0 or M1a) ESCC were enrolled between 2004 and 2011. Radiation therapy (RT) comprised two courses: The first course of radiation covered the primary and metastatic regional tumors and high risk lymph nodal regions, given at 2 Gy per fraction for a dose of 40 Gy. In the second course, LCAHRT was delivered to the boost volume twice a day for an additional 19.6 Gy in 7 treatment days, using 1.4 Gy per fraction. Two cycles of CHT were given at the beginning of RT. The median age and Karnofsky performance status were 63 years and 80, respectively. The American Joint Committee on Cancer stage was II in 14 (20.6%) patients, III in 32 (47.1%), and IVa in 22 (32.3%). With a median follow-up of 18.5 months, the overall survival at 1-, 3-, 5-year were 75.5%, 46.5%, 22.7% for whole group patients, versus 78.6%, 49.4%, 39.9% for patients with stage II–III. The patterns of first failure from local recurrence, regional failure, and distant metastasis were seen in 20.6%, 17.6%, and 19.1%, respectively. The most frequent acute high-grade (≥ 3) toxicities were esophagitis and leucopenia, occurred in 26.4% and 32.4%. ENI LCAHRT concurrently with CHT was appeared to be an effective regimen for ESCC patient with a favorable and tolerated profile. Further observation with longer time and randomized phase III trial is currently underway.

  8. Blood oxygenation level-dependent magnetic resonance imaging during carbogen breathing: differentiation between prostate cancer and benign prostate hyperplasia and correlation with vessel maturity

    Di, Ningning; Mao, Ning; Cheng, Wenna; Pang, Haopeng; Ren, Yan; Wang, Ning; Liu, Xinjiang; Wang, Bin

    2016-01-01

    Objective The aim of this study was to investigate whether the blood oxygenation level-dependent (BOLD) contrast magnetic resonance imaging (MRI) can evaluate tumor maturity and preoperatively differentiate prostate cancer (PCa) from benign prostate hyperplasia (BPH). Patients and methods BOLD MRI based on transverse relaxation time*-weighted echo planar imaging was performed to assess PCa (19) and BPH (22) responses to carbogen (95% O2 and 5% CO2). The average signal values of PCa and BPH before and after carbogen breathing and the relative increased signal values were computed, respectively. The endothelial-cell marker, CD31, and the pericyte marker, α-smooth muscle actin (mature vessels), were detected with immunofluorescence, and were assessed by microvessel density (MVD) and microvessel pericyte density (MPD). The microvessel pericyte coverage index (MPI) was used to evaluate the degree of vascular maturity. The changed signal from BOLD MRI was correlated with MVD, MPD, and MPI. Results After inhaling carbogen, both PCa and BPH showed an increased signal, but a lower slope was found in PCa than that in BPH (PMPI than BPH. The increased signal intensity was positively correlated with MPI in PCa and that in BPH (r=0.616, P=0.011; r=0.658, P=0.002); however, there was no correlation between the increased signal intensity and MPD or MVD in PCa than that in BPH (P>0.05). Conclusion Our results confirmed that the increased signal values induced by BOLD MRI well differentiated PCa from BPH and had a positive correlation with vessel maturity in both of them. BOLD MRI can be utilized as a surrogate marker for the noninvasive assessment of the degree of vessel maturity. PMID:27462169

  9. Radiotherapy cure: safety

    In radiotherapy, a precisely measured dose of ionising radiation is directed at a limited tumour area so as not to damage healthy tissues. The most important form of therapy is external radiation therapy given by means of radiotherapy equipment. The bigger the tumour, the more cancer cells it contains and the higher the radiation dose that is needed to destroy the tumour. Different cancer types respond differently to radiation. Healthy tissues also respond in different ways to radiotherapy, e.g. the reaction may come during the treatment or later. The growth of some cancer types accelerates in two to four weeks after the initiation of the therapy. This information has brought about a reduction in treatment times so as to avoid cell growth that might endanger the treatment result. The radiotherapy that is given today by specialist doctors is safe because the side effects of the treatment are well under control. (orig.)

  10. Accelerated hyperfractionated radiotherapy combined with induction and concomitant chemotherapy for inoperable non-small-cell lung cancer. Impact of total treatment time

    Tumour cell proliferation during conventionally fractionated radiotherapy (RT) can negatively influence the treatment outcome in patients with unresectable non-small-cell lung cancer (NSCLC). Accelerated and hyperfractionated RT may therefore have an advantage over conventional RT. Moreover, earlier studies have suggested improved survival with addition of cisplatin-based chemotherapy (CT). We present here the results of combined treatment with induction and concomitant CT and accelerated hyperfractionated RT in a retrospective series of patients with advanced NSCLS. Between August 1990 and August 1995, 90 consecutive patients, aged 42-77 years (median 63 years), with locally advanced unresectable or medically inoperable NSCLC and good performance status were referred for treatment: stage: I 23%, IIIa 37%, IIIb 40%. Patient histologies included: squamous cell carcinoma 52%, adenocarcinoma 34% and large cell carcinoma 13%. The treatment consisted of two courses of CT (cisplatin 100 mg/m2 day 1 and etoposide 100 mg/m2 day 1-3 i.v.), the second course given concomitantly with RT. The total RT dose was 61.2-64.6 Gy, with two daily fractions of 1.7 Gy. A one-week interval was introduced after 40.8 Gy to reduce acute toxicity, making the total treatment time 4.5 weeks. Concerning toxicity, 33 patients had febrile neutropenia, 10 patients suffered from grade III oesophagitis and 7 patients had grade III pneumonitis. There were two possible treatment-related deaths, one due to myocardial infarction and the other due to a pneumocystis carinii infection. The 1-, 2- and 3-year overall survival rates were 72%, 46% and 34%, respectively; median survival was 21.3 months. Fifty-nine patients had progressive disease: 21 failed locoregionally, 29 had distant metastases and 9 patients had a combination of these. Pretreatment weight loss was the only prognostic factor found, except for stage. However, the results for stage IIIb were no different from those for stage IIIa. We conclude

  11. Rapidly alternating combination of cisplatin-based chemotherapy and hyperfractionated accelerated radiotherapy in split course for Stage IIIA and Stage IIIB non-small cell lung cancer: results of a Phase I-II study by the GOTHA group

    Alberto, P.; Mermillod, B. [Hopital Cantonal Geneve, Geneva (Switzerland); Mirimanoff, R.O.; Leyvraz, S.; Nagy-Mignotte, H.; Bolla, M.; Wellmann, D.; Moro, D.; Brambilla, E. [Hopital Cantonal Universitaire, Lausanne (Switzerland)

    1995-08-01

    The prognosis of stage III non-small cell lung cancer (NSCLC) can be improved by a combination of radiotherapy (RT) and chemotherapy (CT). In this study, the GOTHA group evaluated the feasibility, tolerance, tumour response, pattern of failure and effect on survival of a combination alternating accelerated hyperfractionated (AH) RT and CT in patients with tumour stage III NSCLC. Toxic effects were leucopenia, nausea and vomiting, mucositis, diarrhoea, alopecia and peripheral neuropathy. Alternating CT and AHRT, as used in this study, were well tolerated and allowed full dose delivery within less than 12 weeks. Initial response was not predictive of survival. The survival curve is encouraging and the 5 year survival is superior to the 5% generally observed with conventionally fractionated radiotherapy. (author).

  12. WE-G-BRE-09: Targeted Radiotherapy Enhancement During Accelerated Partial Breast Irradiation (ABPI) Using Controlled Release of Gold Nanoparticles (GNPs)

    Cifter, G; Ngwa, W [University of Massachusetts (United States); Harvard Medical School, Dana Farber Cancer Institute (United States); Chin, J; Cifter, F; Sajo, E [University of Massachusetts (United States); Sinha, N [Wentworth Institute of Technology, Boston, MA (United States); Bellon, J [Harvard Medical School, Dana Farber Cancer Institute (United States)

    2014-06-15

    Purpose: Several studies have demonstrated low rates of local recurrence with brachytherapy-based accelerated partial breast irradiation (APBI). However, long-term outcomes on toxicity (e.g. telangiectasia), and cosmesis remain a major concern. The purpose of this study is to investigate the dosimetric feasibility of using targeted non-toxic radiosensitizing gold nanoparticles (GNPs) for localized dose enhancement to the planning target volume (PTV) during APBI while reducing dose to normal tissue. Methods: Two approaches for administering the GNPs were considered. In one approach, GNPs are assumed to be incorporated in a micrometer-thick polymer film on the surface of routinely used mammosite balloon applicators, for sustained controlled in-situ release, and subsequent treatment using 50-kVp Xoft devices. In case two, GNPs are administered directly into the lumpectomy cavity e.g. via injection or using fiducials coated with the GNP-loaded polymer film. Recent studies have validated the use of fiducials for reducing the PTV margin during APBI with 6 MV beams. An experimentally determined diffusion coefficient was used to determine space-time customizable distribution of GNPs for feasible in-vivo concentrations of 43 mg/g. An analytic calculational approach from previously published work was employed to estimate the dose enhancement due to GNPs (2 and 10 nm) as a function of distance up to 1 cm from lumpectomy cavity. Results: Dose enhancement due to GNP was found to be about 130% for 50-kVp x-rays, and 110% for 6-MV external beam radiotherapy, 1 cm away from the lumpectomy cavity wall. Higher customizable dose enhancement could be achieved at other distances as a function of nanoparticle size. Conclusion: Our preliminary results suggest that significant dose enhancement can be achieved to residual tumor cells targeted with GNPs during APBI with electronic brachytherapy or external beam therapy. The findings provide a useful basis for developing nanoparticle

  13. WE-G-BRE-09: Targeted Radiotherapy Enhancement During Accelerated Partial Breast Irradiation (ABPI) Using Controlled Release of Gold Nanoparticles (GNPs)

    Purpose: Several studies have demonstrated low rates of local recurrence with brachytherapy-based accelerated partial breast irradiation (APBI). However, long-term outcomes on toxicity (e.g. telangiectasia), and cosmesis remain a major concern. The purpose of this study is to investigate the dosimetric feasibility of using targeted non-toxic radiosensitizing gold nanoparticles (GNPs) for localized dose enhancement to the planning target volume (PTV) during APBI while reducing dose to normal tissue. Methods: Two approaches for administering the GNPs were considered. In one approach, GNPs are assumed to be incorporated in a micrometer-thick polymer film on the surface of routinely used mammosite balloon applicators, for sustained controlled in-situ release, and subsequent treatment using 50-kVp Xoft devices. In case two, GNPs are administered directly into the lumpectomy cavity e.g. via injection or using fiducials coated with the GNP-loaded polymer film. Recent studies have validated the use of fiducials for reducing the PTV margin during APBI with 6 MV beams. An experimentally determined diffusion coefficient was used to determine space-time customizable distribution of GNPs for feasible in-vivo concentrations of 43 mg/g. An analytic calculational approach from previously published work was employed to estimate the dose enhancement due to GNPs (2 and 10 nm) as a function of distance up to 1 cm from lumpectomy cavity. Results: Dose enhancement due to GNP was found to be about 130% for 50-kVp x-rays, and 110% for 6-MV external beam radiotherapy, 1 cm away from the lumpectomy cavity wall. Higher customizable dose enhancement could be achieved at other distances as a function of nanoparticle size. Conclusion: Our preliminary results suggest that significant dose enhancement can be achieved to residual tumor cells targeted with GNPs during APBI with electronic brachytherapy or external beam therapy. The findings provide a useful basis for developing nanoparticle

  14. Peripheral dose measurements with diode and thermoluminescence dosimeters for intensity modulated radiotherapy delivered with conventional and un-conventional linear accelerator

    Rajesh Kinhikar

    2013-01-01

    Full Text Available The objective of this paper was to measure the peripheral dose (PD with diode and thermoluminescence dosimeter (TLD for intensity modulated radiotherapy (IMRT with linear accelerator (conventional LINAC, and tomotherapy (novel LINAC. Ten patients each were selected from Trilogy dual-energy and from Hi-Art II tomotherapy. Two diodes were kept at 20 and 25 cm from treatment field edge. TLDs (LiF:MgTi were also kept at same distance. TLDs were also kept at 5, 10, and 15 cm from field edge. The TLDs were read with REXON reader. The readings at the respective distance were recorded for both diode and TLD. The PD was estimated by taking the ratio of measured dose at the particular distance to the prescription dose. PD was then compared with diode and TLD for LINAC and tomotherapy. Mean PD for LINAC with TLD and diode was 2.52 cGy (SD 0.69, 2.07 cGy (SD 0.88 at 20 cm, respectively, while at 25 cm, it was 1.94 cGy (SD 0.58 and 1.5 cGy (SD 0.75, respectively. Mean PD for tomotherapy with TLD and diode was 1.681 cGy SD 0.53 and 1.58 (SD 0.44 at 20 cm, respectively. The PD was 1.24 cGy (SD 0.42 and 1.088 cGy (SD 0.35 at 25 cm, respectively, for tomotherapy. Overall, PD from tomotherapy was found lower than LINAC by the factor of 1.2-1.5. PD measurement is essential to find out the potential of secondary cancer. PD for both (conventional LINAC and novel LINACs (tomotherapy were measured and compared with each other. The comparison of the values for PD presented in this work and those published in the literature is difficult because of the different experimental conditions. The diode and TLD readings were reproducible and both the detector readings were comparable.

  15. Modelling accelerated fractionation in radiotherapy

    This study was undertaken to investigate optimum treatment schedules for highly proliferative tumours. The linear quadratic model is used to predict the most effective fractionation regimes. It should be pointed out that greater early effects are associated with improved tumour control, as such these data should be treated as a useful guideline and should never be used out of context with clinical experience. The linear quadratic model with proliferation has been used to investigate the effect on cell survival and associated tumour control probability (TCP)

  16. Concurrent hyperfractionated accelerated radiotherapy with 5-FU and once weekly cisplatin in locally advanced head and neck cancer. The 10-year results of a prospective phase II trial

    Budach, V.; Boehmer, D.; Badakhshi, H.; Jahn, U.; Stromberger, C. [Campus Virchow Klinikum, Charite Universitaetsmedizin Berlin, Department for Radiooncology, Clinic for Radiooncology, Berlin (Germany); Becker, E.T. [Charite Universitaetsmedizin, Department of Otorhinolaryngology, Berlin (Germany); Wernecke, K.D. [Sostana Statistics GmbH, Charite Universitaetsmedizin Berlin, Berlin (Germany)

    2014-03-15

    In this study, the acute toxicity and long-term outcome of a hyperfractionated accelerated chemoradiation regimen with cisplatin/5-fluorouracil (5-FU) in patients with locally advanced squamous cell carcinomas of head and neck were evaluated. From 2000-2002, 38 patients with stage III (5.3 %) and stage IV (94.7 %) head and neck cancer were enrolled in a phase II study. Patients received hyperfractionated-accelerated radiotherapy with 72 Gy in 15 fractions of 2 Gy followed by 1.4 Gy twice daily with concurrent, continuous infusion 5-FU of 600 mg/m{sup 2} on days 1-5 and 6 cycles of weekly cisplatin (30 mg/m{sup 2}). Acute toxicities (CTCAEv2.0), locoregional control (LRC), metastases-free (MFS), and overall survival (OS) were analyzed and exploratively compared with the ARO 95-06 trial. Median follow-up was 11.4 years (95 % CI 8.6-14.2) and mean dose 71.6 Gy. Of the patients, 82 % had 6 (n = 15) or 5 (n = 16) cycles of cisplatin, 5 and 2 patients received 4 and 3 cycles, respectively. Grade 3 anemia, leukopenia, and thrombocytopenia were observed in 15.8, 15.8, and 2.6 %, respectively. Grade 3 mucositis in 50 %, grade 3 and 4 dysphagia in 55 and 13 %. The 2-, 5-, and 10-year LRC was 65, 53.6, and 48.2 %, the MFS was 77.5, 66.7, and 57.2 % and the OS 59.6, 29.2, and 15 %, respectively. Chemoradiation with 5-FU and cisplatin seems feasible and superior in terms of LRC and OS to the ARO 95-06C-HART arm at 2 years. However, this did not persist at the 5- and 10-year follow-ups. (orig.) [German] Untersuchung der Akuttoxizitaet und des Langzeitueberlebens einer hyperfraktioniert-akzelerierten simultanen Radiochemotherapie mit Cisplatin/5-Fluorouracil (5-FU) bei Patienten mit lokal fortgeschrittenen Kopf-Hals-Tumoren. Von 2000 bis 2002 wurden 38 Patienten mit Plattenepithelkarzinomen der Kopf-Hals-Region im Stadium III (5,3 %) und IV (94,7 %) eingeschlossen. Es erfolgte eine simultane hyperfraktionierte akzelerierte Radiochemotherapie mit 72 Gy in 15 Fraktionen a 2 Gy

  17. IAEA-HypoX. A randomized multicenter study of the hypoxic radiosensitizer nimorazole concomitant with accelerated radiotherapy in head and neck squamous cell carcinoma

    Purpose: To test the hypothesis that radiotherapy (RT) of head and neck squamous cell carcinoma (HNSCC) can be improved by hypoxic modification using nimorazole (NIM) in association with accelerated fractionation. Materials and methods: The protocol was activated in March 2012 as an international multicenter randomized trial in patients with HNSCC. Tumors were treated to a dose of 66–70 Gy, 33–35 fractions, 6 fractions per week. NIM was administered in a dose of 1.2 g per m2, 90 min before the first daily RT fraction. The primary endpoint was loco-regional failure. The trial was closed prematurely by June 2014 due to poor recruitment. An associated quality assurance program was performed to ensure the consistency of RT with the protocol guidelines. Results: The trial was dimensioned to include 600 patients in 3 years, but only 104 patients were randomized between March 2012 and May 2014 due to the inability to involve three major centers and the insufficient recruitment rate from the other participating centers. Twenty patients from two centers had to be excluded from the analysis due to the unavailability of the follow-up data. Among the remaining 84 patients, 82 patients were evaluable (39 and 43 patients in the RT + NIM and the RT-alone arms, respectively). The treatment compliance was good with only six patients not completing the full planned RT course, and 31 patients (79%) out of 39 allocated for NIM, achieving at least 90% of the prescribed drug dose. At the time of evaluation, 40 patients had failed to achieve persistent loco-regional tumor control, and a total of 45 patients had died. The use of NIM improved the loco-regional tumor control with an 18 month post-randomization cumulative failure rate of 33% versus 51% in the control arm, yielding a risk difference of 18% (CI −3% to 39%; P = 0.10). The corresponding values for overall death was 43% versus 62%, yielding a risk difference of 19% (CI −3% to 42%; P = 0.10). Sixteen patients, out of 55

  18. Quantitative analysis of results of quality control tests in linear accelerators used in radiotherapy; Analise quantitativa dos resultados de testes de controle de qualidade em aceleradores lineares usados em radioterapia

    Passaro, Bruno M.; Rodrigues, Laura N. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Videira, Heber S., E-mail: bruno.passaro@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

    2013-04-15

    The aim of this study is to assess and analyze the stability of the calibration factor of three linear accelerators, as well as the other dosimetric parameters normally included in a program of quality control in radiotherapy. The average calibration factors of the accelerators for the period of approximately four years for the Clinac 600C and Clinac 6EX were (0.998±0.012) and (0.996±0.014), respectively. For the Clinac 2100CD 6 MV and 15 MV was (1.008±0.009) and (1.006±0.010), respectively, in a period of approximately four years. The data of the calibration factors were divided into four subgroups for a more detailed analysis of behavior over the years. Through statistical analysis of calibration factors, we found that for the 600C and Clinacs 2100CD, is an expected probability that more than 90% of cases the values are within acceptable ranges according to TG-142, while for the Clinac 6EX is expected around 85% since this had several exchanges of accelerator components. The values of TPR20,10 of three accelerators are practically constant and within acceptable limits according to the TG-142. It can be concluded that a detailed study of data from the calibration factor of the accelerators and TPR{sub 20},{sub 10} from a quantitative point of view, is extremely useful in a quality assurance program. (author)

  19. Dose escalation of accelerated hypofractionated three-dimensional conformal radiotherapy (at 3 Gy/fraction) with concurrent vinorelbine and carboplatin chemotherapy in unresectable stage III non-small-cell lung cancer: a phase I trial

    Accelerated hypofractionated radiotherapy can shorten total treatment time and overcome the accelerated repopulation of tumour cells during radiotherapy. This therapeutic approach has demonstrated good efficacy in the treatment of locally advanced non-small-cell lung cancer (NSCLC). However, the optimal fractionation scheme remains uncertain. The purpose of this phase I trial was to explore the maximum tolerated dose (MTD) of accelerated hypofractionated three-dimensional conformal radiotherapy (3-DCRT) (at 3 Gy/fraction) administered in combination with concurrent vinorelbine (NVB) and carboplatin (CBP) chemotherapy for unresectable stage III NSCLC. Previously untreated cases of unresectable stage III NSCLC received accelerated hypofractionated 3-DCRT, delivered at 3 Gy per fraction, once daily, with five fractions per week. The starting dose was 66 Gy and an increment of 3 Gy was utilized. Higher doses continued to be tested in patient groups until the emergence of dose-limiting toxicity (DLT). The MTD was regarded as the dose that was one step below the dose at which DLT occurred. Patients received at least one cycle of a concurrent two-drug chemotherapy regimen of NVB and CBP. A total of 13 patients were enrolled and progressed through three dose escalation groups: 66 Gy, 69 Gy, and 72 Gy. No treatment-related deaths occurred. The major adverse events included radiation oesophagitis, radiation pneumonitis, and neutropenia. Nausea, fatigue, and anorexia were commonly observed, although the magnitude of these events was typically relatively minor. Among the entire group, four instances of DLT were observed, including two cases of grade 3 radiation oesophagitis, one case of grade 3 radiation pneumonitis, and one case of grade 4 neutropenia. All of these cases of DLT occurred in the 72 Gy group. Therefore, 72 Gy was designated as the DLT dose level, and the lower dose of 69 Gy was regarded as the MTD. For unresectable stage III NSCLC 69 Gy (at 3 Gy/fraction) was

  20. Long-Term Outcome and Morbidity After Treatment With Accelerated Radiotherapy and Weekly Cisplatin for Locally Advanced Head-and-Neck Cancer: Results of a Multidisciplinary Late Morbidity Clinic

    Ruetten, Heidi, E-mail: h.rutten@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Pop, Lucas A.M.; Janssens, Geert O.R.J. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Takes, Robert P. [Department of Otorhinolaryngology and Head and Neck Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Knuijt, Simone [Department of Rehabilitation/Speech Pathology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Rooijakkers, Antoinette F. [Department of Oral and Maxillofacial Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Berg, Manon van den [Department of Gastroenterology-Dietetics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Merkx, Matthias A. [Department of Oral and Maxillofacial Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Herpen, Carla M.L. van [Department of Medical Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kaanders, Johannes H.A.M. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2011-11-15

    Purpose: To evaluate the long-term outcome and morbidity after intensified treatment for locally advanced head-and-neck cancer. Methods and Materials: Between May 2003 and December 2007, 77 patients with Stage III to IV head-and-neck cancer were treated with curative intent. Treatment consisted of accelerated radiotherapy to a dose of 68 Gy and concurrent cisplatin. Long-term survivors were invited to a multidisciplinary outpatient clinic for a comprehensive assessment of late morbidity with special emphasis on dysphagia, including radiological evaluation of swallowing function in all patients. Results: Compliance with the treatment protocol was high, with 87% of the patients receiving at least five cycles of cisplatin and all but 1 patient completing the radiotherapy as planned. The 5-year actuarial disease-free survival and overall survival rates were 40% and 47%, respectively. Locoregional recurrence-free survival at 5 years was 61%. The 5-year actuarial rates of overall late Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) Grade 3 and Grade 4 toxicity were 52% and 25% respectively. Radiologic evaluation after a median follow-up of 44 months demonstrated impaired swallowing in 57% of the patients, including 23% with silent aspiration. Subjective assessment using a systematic scoring system indicated normalcy of diet in only 15.6% of the patients. Conclusion: This regimen of accelerated radiotherapy with weekly cisplatin produced favorable tumor control rates and survival rates while compliance was high. However, comprehensive assessment by a multidisciplinary team of medical and paramedical specialists revealed significant long-term morbidity in the majority of the patients, with dysphagia being a major concern.

  1. Long-Term Outcome and Morbidity After Treatment With Accelerated Radiotherapy and Weekly Cisplatin for Locally Advanced Head-and-Neck Cancer: Results of a Multidisciplinary Late Morbidity Clinic

    Purpose: To evaluate the long-term outcome and morbidity after intensified treatment for locally advanced head-and-neck cancer. Methods and Materials: Between May 2003 and December 2007, 77 patients with Stage III to IV head-and-neck cancer were treated with curative intent. Treatment consisted of accelerated radiotherapy to a dose of 68 Gy and concurrent cisplatin. Long-term survivors were invited to a multidisciplinary outpatient clinic for a comprehensive assessment of late morbidity with special emphasis on dysphagia, including radiological evaluation of swallowing function in all patients. Results: Compliance with the treatment protocol was high, with 87% of the patients receiving at least five cycles of cisplatin and all but 1 patient completing the radiotherapy as planned. The 5-year actuarial disease-free survival and overall survival rates were 40% and 47%, respectively. Locoregional recurrence–free survival at 5 years was 61%. The 5-year actuarial rates of overall late Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) Grade 3 and Grade 4 toxicity were 52% and 25% respectively. Radiologic evaluation after a median follow-up of 44 months demonstrated impaired swallowing in 57% of the patients, including 23% with silent aspiration. Subjective assessment using a systematic scoring system indicated normalcy of diet in only 15.6% of the patients. Conclusion: This regimen of accelerated radiotherapy with weekly cisplatin produced favorable tumor control rates and survival rates while compliance was high. However, comprehensive assessment by a multidisciplinary team of medical and paramedical specialists revealed significant long-term morbidity in the majority of the patients, with dysphagia being a major concern.

  2. Aggressive simultaneous radiochemotherapy with cisplatin and paclitaxel in combination with accelerated hyperfractionated radiotherapy in locally advanced head and neck tumors. Results of a phase I-II trial

    Kuhnt, T.; Pigorsch, S.; Pelz, T.; Haensgen, G.; Dunst, J. [Dept. of Radiotherapy, Martin Luther Univ., Halle (Germany); Becker, A. [Dept. of Radiotherapy, Martin Luther Univ., Halle (Germany); Dept. of Radiotherapy, Municipial Hospital, Dessau (Germany); Bloching, M.; Passmann, M. [Dept. of Head and Neck Surgery, Martin Luther Univ., Halle (Germany); Lotterer, E. [Dept. of Internal Medicine I, Martin Luther Univ., Halle (Germany)

    2003-10-01

    We have tested a very aggressive combination protocol with cisplatin and escalated paclitaxel in combination with accelerated hyperfractionated radiotherapy to assess the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), overall toxicity, and response rate. Patients and Methods: The trial recruited 24 patients (21 males, three females, mean age 57 years) treated at our department from 1998 through 2001. Irradiation was administered in daily doses of 2 Gy up to 30 Gy followed by 1.4 Gy twice daily up to 70.6 Gy to the primary tumor and involved nodes and 51 Gy to the clinically negative regional nodes. The chemotherapy schedule included cisplatin in a fixed dose of 20 mg/m{sup 2} on days 1-5 and 29-33 and paclitaxel at increasing dose levels of 20, 25, 30 mg/m{sup 2} twice weekly over the whole treatment time. Patients were recruited in cohorts of three to six, and the MTD was reached if two out of six patients in one cohort developed DLT. DLT was defined as any grade 4 toxicity or any grade 3 toxicity requiring treatment interruption or unplanned hospitalization or any grade 3 neurotoxicity. We recruited mainly patients with large tumors for this protocol; all patients were stage IV, and the mean tumor volume (primary + metastases) amounted to 72 {+-} 61 cm{sup 3}. The mean follow-up was 30 months (range 4-39 months). Results: One early death (peritonitis and sepsis a t day 10) occurred, and 23 patients were evaluable for acute toxicity and response. The MTD of paclitaxel was reached at the third dose level (30 mg/m{sup 2} paclitaxel twice weekly). The DLT was severe mucositis grade 3 (n = 1) and skin erythema grade 4 (n = 2). After determining the MTD, another 14 patients were treated at the recommended dose level of paclitaxel with 25 mg/m{sup 2} twice weekly. In summary, 13/23 patients (57%) developed grade 3 and 10/23 (43%) grade 2 mucositis. Two patients (9%) had grade 4, five (22%) grade 3, and 16 (69%) grade 2 dermatitis. One patient died at day 30

  3. Clinical application of AcMAR (accelerated multiple-arc radiotherapy) for head and neck tumors. Results of a randomized, two-dose study in Kitami Red-Cross General Hospital

    Enhanced acute mucositis is the limiting factor for accelerated, hyperfractionated radiotherapy in head and neck (H and N) squamous cell carcinomas (SCCs). We have developed a simple, new form of conformal radiotherapy, accelerated multiple arc radiotherapy (AcMAR), which covers the target volume by combined, segmental, and rotational arc fields. Two to three rotational fields were placed with CT guidance, each covering the primary tumor and lymph nodes separately. The optimal inter-isocenter distance was determined by 3D dose calculation. The surface area of oro-pharyngeal mucosa irradiated by more than a 50% dose by this method was reduced by 37-73% compared to that with a conventional parallel opposing technic. Dose searching, randomized two-dose study was initiated in Kitami Red-cross General Hospital (KRCGH) in January 1995, and 101 patients were registered and completed AcMAR in Oct 2000. All the patients were followed for up to 96 months (24-96 mo, median 48 mo) at the time of analysis. Fifty-one out of 101 patients were Stage III (17) and IV (34). Primary site of tumors were; 38 larynx, 25 oropharynx, 15 hypopharynx, 13 oral cavity, and 10 other miscellaneous sites. Patients were randomly allocated either to 60 Gy/24 fr/bid/3 wks to gross tumor volume (GTV) (Group A), or 66 Gy/33 fr/bid/4 wks to GTV (Group B). Forty Gy/16 fr/bid/2 wks was given to the volume of prophylactic'' irradiation in both groups of patients. Results were as follows: All the patients, except for one, completed AcMAR without treatment interruption. Acute mucositis at the site of high-dose irradiation was intense; 72% of Group A and 62.5% of Group B experienced World Health Organization (WHO) Grade 3 (confluent) mucositis focally. Fifty-one out of 53 in Group A and 48/48 in Group B, however, could maintain oral food intake (WHO Grade 1 or 2) even at the peak of their mucositis, because of the limited area of severe mucositis. With regard to late morbidity, however, 6/46 (followed >24 mo

  4. Evaluation of a combined respiratory-gating system comprising the TrueBeam linear accelerator and a new real-time tumor-tracking radiotherapy system: a preliminary study.

    Shiinoki, Takehiro; Kawamura, Shinji; Uehara, Takuya; Yuasa, Yuki; Fujimoto, Koya; Koike, Masahiro; Sera, Tatsuhiro; Emoto, Yuki; Hanazawa, Hideki; Shibuya, Keiko

    2016-01-01

    A combined system comprising the TrueBeam linear accelerator and a new real-time, tumor-tracking radiotherapy system, SyncTraX, was installed in our institution. The goals of this study were to assess the capability of SyncTraX in measuring the position of a fiducial marker using color fluoroscopic images, and to evaluate the dosimetric and geometric accuracy of respiratory-gated radiotherapy using this combined system for the simple geometry. For the fundamental evaluation of respiratory-gated radiotherapy using SyncTraX, the following were performed:1) determination of dosimetric and positional characteristics of sinusoidal patterns using a motor-driven base for several gating windows; 2) measurement of time delay using an oscilloscope; 3) positional verification of sinusoidal patterns and the pattern in the case of a lung cancer patient; 4) measurement of the half-value layer (HVL in mm AL), effective kVp, and air kerma, using a solid-state detector for each fluoroscopic condition, to determine the patient dose. The dose profile in a moving phantom with gated radiotherapy having a gating window ≤ 4 mm was in good agreement with that under static conditions for each photon beam. The total time delay between TrueBeam and SyncTraX was lung cancer patient. The air-kerma rates from one fluoroscopy direction were 1.93 ± 0.01, 2.86 ± 0.01, 3.92 ± 0.04, 5.28 ± 0.03, and 6.60 ± 0.05 mGy/min for 70, 80, 90, 100, and 110 kV X-ray beams at 80 mA, respectively. The combined system comprising TrueBeam and SyncTraX could track the motion of the fiducial marker and control radiation delivery with reasonable accuracy; therefore, this system provides significant dosimetric improvement. However, patient exposure dose from fluoroscopy was not clinically negligible. PMID:27455483

  5. Construction of a remote radiotherapy planning system

    We constructed a remote radiotherapy planning system, and we examined the usefulness of and faults in our system in this study. Two identical radiotherapy planning systems, one installed at our institution and the other installed at an affiliated hospital, were used for radiotherapy planning. The two systems were connected by a wide area network (WAN), using a leased line. Beam data for the linear accelerator at the affiliated hospital were installed in the two systems. During the period from December 2001 to December 2002, 43 remote radiotherapy plans were made using this system. Data were transmitted using a file transfer protocol (FTP) software program. The 43 radiotherapy plans examined in this study consisted of 13 ordinary radiotherapy plans, 28 radiotherapy plans sent to provide assistance for medical residents, and 2 radiotherapy plans for emergency cases. There were ten minor planning changes made in radiotherapy plans sent to provide assistance for medical residents. Our remote radiotherapy planning system based on WAN using a leased line is useful for remote radiotherapy, with advantages for both radiation oncologists and medical residents. (author)

  6. Radiotherapy: yesterday, today and tomorrow

    The inaugural lecture starts with a brief history of the discovery of x-rays and the development of radiotherapy. In a modern radiotherapy department, cancer is diagnosed and mostly treated non-surgically. The modern treatment of many cancers is complex and involves a choice between at least 3 modalities; namely surgery, radiotherapy and cancer chemotherapy. One or a combination of these can be used. A discussion is given of a radiotherapy department as it functions at the University of Cape Town. At the University, cancer is not managed by any one treatment modality, but by a group of specialists who have a major intersest in a particular field. The personnel of the radiotherapy department consists of various people such as a radiographer, radiotherapist, radiobiologist and others, who are all experts in a particular area. Together they form the radiotherapy team. An individual treatment plan is drawn up for each patient. An indication is given of the cost of a major linear accelerator and the patient treatment cost on such an accelerator. Cancer chemotherapy comprises an important part in any radiotherapy department and is used to prevent the appearance of microscopic disease or to reduce and even cure established disease. A summary is given of the cost attached to chemotherapy. An indication of cure rates with the present methods of treatment is given. The reason why oxygen is necessary in the radiation of tumours is discussed. The radiobiologist plays an important role in this respect. A look is also taken at the future prospects of radiotherapy

  7. Preliminary Experience in Treatment of Papillary and Macular Retinoblastoma: Evaluation of Local Control and Local Complications After Treatment With Linear Accelerator-Based Stereotactic Radiotherapy With Micromultileaf Collimator as Second-Line or Salvage Treatment After Chemotherapy

    Pica, Alessia, E-mail: Alessia.Pica@chuv.ch [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Moeckli, Raphael [University Institute for Radiation Physics, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Balmer, Aubin [Department of Radiation Oncology, Jules Gonin Eye Hospital, Lausanne (Switzerland); Beck-Popovic, Maja [Unit of Pediatric Oncology, University of Lausanne, Lausanne (Switzerland); Chollet-Rivier, Madeleine [Department of Anesthesiology, University of Lausanne, Lausanne (Switzerland); Do, Huu-Phuoc [University Institute for Radiation Physics, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Weber, Damien C. [Department of Radiation Oncology, Geneva University Hospital, University of Geneva, Geneva (Switzerland); Munier, Francis L. [Department of Radiation Oncology, Jules Gonin Eye Hospital, Lausanne (Switzerland)

    2011-12-01

    Purpose: To determine the local control and complication rates for children with papillary and/or macular retinoblastoma progressing after chemotherapy and undergoing stereotactic radiotherapy (SRT) with a micromultileaf collimator. Methods and Materials: Between 2004 and 2008, 11 children (15 eyes) with macular and/or papillary retinoblastoma were treated with SRT. The mean age was 19 months (range, 2-111). Of the 15 eyes, 7, 6, and 2 were classified as International Classification of Intraocular Retinoblastoma Group B, C, and E, respectively. The delivered dose of SRT was 50.4 Gy in 28 fractions using a dedicated micromultileaf collimator linear accelerator. Results: The median follow-up was 20 months (range, 13-39). Local control was achieved in 13 eyes (87%). The actuarial 1- and 2-year local control rates were both 82%. SRT was well tolerated. Late adverse events were reported in 4 patients. Of the 4 patients, 2 had developed focal microangiopathy 20 months after SRT; 1 had developed a transient recurrence of retinal detachment; and 1 had developed bilateral cataracts. No optic neuropathy was observed. Conclusions: Linear accelerator-based SRT for papillary and/or macular retinoblastoma in children resulted in excellent tumor control rates with acceptable toxicity. Additional research regarding SRT and its intrinsic organ-at-risk sparing capability is justified in the framework of prospective trials.

  8. Preliminary Experience in Treatment of Papillary and Macular Retinoblastoma: Evaluation of Local Control and Local Complications After Treatment With Linear Accelerator-Based Stereotactic Radiotherapy With Micromultileaf Collimator as Second-Line or Salvage Treatment After Chemotherapy

    Purpose: To determine the local control and complication rates for children with papillary and/or macular retinoblastoma progressing after chemotherapy and undergoing stereotactic radiotherapy (SRT) with a micromultileaf collimator. Methods and Materials: Between 2004 and 2008, 11 children (15 eyes) with macular and/or papillary retinoblastoma were treated with SRT. The mean age was 19 months (range, 2–111). Of the 15 eyes, 7, 6, and 2 were classified as International Classification of Intraocular Retinoblastoma Group B, C, and E, respectively. The delivered dose of SRT was 50.4 Gy in 28 fractions using a dedicated micromultileaf collimator linear accelerator. Results: The median follow-up was 20 months (range, 13–39). Local control was achieved in 13 eyes (87%). The actuarial 1- and 2-year local control rates were both 82%. SRT was well tolerated. Late adverse events were reported in 4 patients. Of the 4 patients, 2 had developed focal microangiopathy 20 months after SRT; 1 had developed a transient recurrence of retinal detachment; and 1 had developed bilateral cataracts. No optic neuropathy was observed. Conclusions: Linear accelerator-based SRT for papillary and/or macular retinoblastoma in children resulted in excellent tumor control rates with acceptable toxicity. Additional research regarding SRT and its intrinsic organ-at-risk sparing capability is justified in the framework of prospective trials.

  9. Solid state tuneable power RF source for S-band klystron used in the indigenous development of medical linear accelerator for radiotherapy

    Medical Linear Accelerators (LINAC) are being widely used in the treatment of the cancer patients. The requirement of the energy and the particle type depends on the tumour site and its volume. Hence, it is a necessary to design and develop the multiple energy electron medical accelerators. We have successfully indigenously developed, installed and commissioned the 4 MV (Jeevan-Jyoti) and 6 MV (Siddarth) machines for this purpose. The said machines have been type approved by Atomic Energy Regulatory Board (AERB), Mumbai for the treatment of cancer patient. After this achievement we have taken up the project to design and develop the dual mode (Photon and Electron) multiple energy Medical Accelerator. This LINAC will deliver the two photon energies of 6 and 10 MV, whereas five electron energies viz. 6, 9, 12, 15 and 18 MeV. The system has various sub system such as Linear accelerator (radiation source), High power Modulator, Microwave system based on Klystron, Gantry, Patient Support Assembly, Dosimetry, Beam limiting system, control console, etc. In conclusion, we have successfully achieved the precise variation of RF power using this RF source which will be input to klystron amplifier and the accelerator will produce the different energies as per the treatment requirement using the FPGA based control system

  10. Accelerated high-dose radiotherapy alone or combined with either concomitant or sequential chemotherapy; treatments of choice in patients with Non-Small Cell Lung Cancer

    Results of high-dose chemo-radiotherapy (CRT), using the treatment schedules of EORTC study 08972/22973 or radiotherapy (RT) alone were analyzed among all patients (pts) with Non Small Cell Lung Cancer (NSCLC) treated with curative intent in our department from 1995–2004. Included are 131 pts with medically inoperable or with irresectable NSCLC (TNM stage I:15 pts, IIB:15 pts, IIIA:57 pts, IIIB:43 pts, X:1 pt). Group I: Concomitant CRT: 66 Gy/2.75 Gy/24 fractions (fx)/33 days combined with daily administration of cisplatin 6 mg/m2: 56 pts (standard). Group II: Sequential CRT: two courses of a 21-day schedule of chemotherapy (gemcitabin 1250 mg/m2 d1, cisplatin 75 mg/m2 d2) followed by 66 Gy/2.75 Gy/24 fx/33 days without daily cisplatin: 26 pts. Group III: RT: 66 Gy/2.75 Gy/24 fx/33 days or 60 Gy/3 Gy/20 fx/26 days: 49 pts. The 1, 2, and 5 year actuarial overall survival (OS) were 46%, 24%, and 15%, respectively. At multivariate analysis the only factor with a significantly positive influence on OS was treatment with chemo-radiation (P = 0.024) (1-, 2-, and 5-yr OS 56%, 30% and 22% respectively). The incidence of local recurrence was 36%, the incidence of distant metastases 46%. Late complications grade 3 were seen in 21 pts and grade 4 in 4 patients. One patient had a lethal complication (oesophageal). For 32 patients insufficient data were available to assess late complications. In this study we were able to reproduce the results of EORTC trial 08972/22973 in a non-selected patient population outside of the setting of a randomised trial. Radiotherapy (66 Gy/24 fx/33 days) combined with either concomitant daily low dose cisplatin or with two neo-adjuvant courses of gemcitabin and cisplatin are effective treatments for patients with locally advanced Non-Small Cell Lung Cancer. The concomitant schedule is also suitable for elderly people with co-morbidity

  11. A strategy for the use of image-guided radiotherapy (IGRT) on linear accelerators and its impact on treatment margins for prostate cancer patients

    In external beam radiotherapy of prostate cancer, the consideration of various systematic error types leads to wide treatment margins compromising normal tissue tolerance. We investigated if systematic set-up errors can be reduced by a set of initial image-guided radiotherapy (IGRT) sessions. 27 patients received daily IGRT resulting in a set of 882 cone-beam computed tomographies (CBCTs). After matching to bony structures, we analyzed the dimensions of remaining systematic errors from zero up to six initial IGRT sessions and aimed at a restriction of daily IGRT for 10% of all patients. For threshold definition, we determined the standard deviations (SD) of the shift corrections and selected patients out of this range for daily image guidance. To calculate total treatment margins, we demanded for a cumulative clinical target volume (CTV) coverage of at least 95% of the specified dose in 90% of all patients. The gain of accuracy was largest during the first three IGRTs. In order to match precision and workload criteria, thresholds for the SD of the corrections of 3.5 mm, 2.0 mm and 4.5 mm in the left-right (L-R), cranial-caudal (C-C), and anterior-posterior (A-P) direction, respectively, were identified. Including all other error types, the total margins added to the CTV amounted to 8.6 mm in L-R, 10.4 mm in C-C, and 14.4 mm in A-P direction. Only initially performed IGRT might be helpful for eliminating gross systematic errors especially after virtual simulation. However, even with daily IGRT performance, a substantial PTV margin reduction is only achievable by matching internal markers instead of bony anatomical structures. (orig.)

  12. How Do the ASTRO Consensus Statement Guidelines for the Application of Accelerated Partial Breast Irradiation Fit Intraoperative Radiotherapy? A Retrospective Analysis of Patients Treated at the European Institute of Oncology

    Purpose: To verify how the classification according to the American Society for Therapeutic Radiation Oncology (ASTRO) consensus statement (CS) for the application of accelerated partial breast irradiation (APBI) fits patients treated with intraoperative radiotherapy with electrons (ELIOT) at a single institution. Methods and Materials: The study included 1,822 patients treated with ELIOT as the sole radiation modality outside of a clinical trial at the European Institute of Oncology after breast-conserving surgery for invasive breast cancer, who were classified into CS groups of suitable, cautionary, and unsuitable. The outcome in terms of ipsilateral breast recurrence, regional node relapse, distant metastases, progression free-survival, cause-specific survival, and overall survival were assessed. Results: All the 1,822 cases except for 25 could be classified according to ASTRO CS: 294 patients met the criteria for inclusion into the suitable group, 691 patients into the cautionary group, and 812 patients into the unsuitable group. The 5-year rate of ipsilateral breast recurrence for suitable, cautionary, and unsuitable groups were 1.5%, 4.4%, and 8.8%, respectively (p = 0.0003). Whereas the regional node relapse showed no difference, the rate of distant metastases was significantly different in the unsuitable group compared with the suitable and cautionary groups, having a significant impact on survival. Conclusion: In the context of patients treated with ELIOT, the ASTRO guidelines identify well the groups for whom APBI might be considered as an effective alternative to whole breast radiotherapy and also identify groups for whom APBI is not indicated.

  13. Final results of the randomized phase III CHARTWEL-trial (ARO 97-1) comparing hyperfractionated-accelerated versus conventionally fractionated radiotherapy in non-small cell lung cancer (NSCLC)

    Background: Continuous hyperfractionated accelerated radiotherapy (CHART) counteracts repopulation and may significantly improve outcome of patients with non-small-cell lung cancer (NSCLC). Nevertheless high local failure rates call for radiation dose escalation. We report here the final results of the multicentric CHARTWEL trial (CHART weekend less, ARO 97-1). Patients and methods: Four hundred and six patients with NSCLC were stratified according to stage, histology, neoadjuvant chemotherapy and centre and were randomized to receive 3D-planned radiotherapy to 60 Gy/40 fractions/2.5 weeks (CHARTWEL) or 66 Gy/33 fractions/6.5 weeks (conventional fractionation, CF). Results: Overall survival (OS, primary endpoint) at 2, 3 and 5 yr was not significantly different after CHARTWEL (31%, 22% and 11%) versus CF (32%, 18% and 7%; HR 0.92, 95% CI 0.75-1.13, p = 0.43). Also local tumour control rates and distant metastases did not significantly differ. Acute dysphagia and radiological pneumonitis were more pronounced after CHARTWEL, without differences in clinical signs of pneumopathy. Exploratory analysis revealed a significant trend for improved LC after CHARTWEL versus CF with increasing UICC, T or N stage (p = 0.006-0.025) and after neoadjuvant chemotherapy (HR 0.48, 0.26-0.89, p = 0.019). Conclusions: Overall, outcome after CHARTWEL or CF was not different. The lower total dose in the CHARTWEL arm was compensated by the shorter overall treatment time, confirming a time factor for NSCLC. The higher efficacy of CHARTWEL versus CF in advanced stages and after chemotherapy provides a basis for further trials on treatment intensification for locally advanced NSCLC.

  14. Treatment machines for external beam radiotherapy

    Since the inception of radiotherapy soon after the discovery of X rays by Roentgen in 1895, the technology of X ray production has first been aimed towards ever higher photon and electron beam energies and intensities, and more recently towards computerization and intensity modulated beam delivery. During the first 50 years of radiotherapy the technological progress was relatively slow and mainly based on X ray tubes, van de Graaff generators and betatrons. The invention of the 60Co teletherapy unit by H.E. Johns in Canada in the early 1950s provided a tremendous boost in the quest for higher photon energies and placed the cobalt unit at the forefront of radiotherapy for a number of years. The concurrently developed medical linacs, however, soon eclipsed cobalt units, moved through five increasingly sophisticated generations and became the most widely used radiation source in modern radiotherapy. With its compact and efficient design, the linac offers excellent versatility for use in radiotherapy through isocentric mounting and provides either electron or megavoltage X ray therapy with a wide range of energies. In addition to linacs, electron and X ray radiotherapy is also carried out with other types of accelerator, such as betatrons and microtrons. More exotic particles, such as protons, neutrons, heavy ions and negative p mesons, all produced by special accelerators, are also sometimes used for radiotherapy; however, most contemporary radiotherapy is carried out with linacs or teletherapy cobalt units

  15. Determination of radiation levels by neutrons in an accelerator for radiotherapy; Determinacion de niveles de radiacion por neutrones en un acelerador para radioterapia

    Paredes G, L.; Salazar B, M.A. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico D.F. (Mexico); Genis S, R. [Fundacion Clinica Medica Sur, Puente de Piedra 150, Col. Torriello Guerra, Tlalpan 14050, Mexico D.F. (Mexico)

    1998-12-31

    It was determined the radiation levels by neutrons due to photonuclear reactions ({gamma}, n) which occur in the target, levelling filter, collimators and the small pillow blinding of a medical accelerator Varian Clinac 2100C of 18 MeV, using thermoluminescent dosemeters UD-802AS and US-809AS. The experimental values were presented for the patient level, inside and outside of the radiation field, as well as for the small pillow. (Author)

  16. The spanish radiotherapy park: past and present

    The present article has as objective to provide a general overview on the spanish radiotherapy park, presenting how was its start and evolution until the current state. Considering only the units of teletherapy and the accelerators. Actually in Spain there is 28 units of Cobalt therapy, in functioning during the last two decades, being advised a rapid substitution to accelerators

  17. Radiotherapy; Strahlentherapie

    Wannenmacher, M. [Heidelberg Univ., Mannheim (Germany). Abt. fuer Klinische Radiologie; Debus, J. [Univ. Heidelberg (Germany). Abt. Radioonkologie und Strahlentherapie; Wenz, F. (eds.) [Universitaetsklinikum Mannheim (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2006-07-01

    The book is focussed on the actual knowledge on the clinical radiotherapy and radio-oncology. Besides fundamental and general contributions specific organ systems are treated in detail. The book contains the following contributions: Basic principles, radiobiological fundamentals, physical background, radiation pathology, basics and technique of brachytherapy, methodology and technique of the stereotactic radiosurgery, whole-body irradiation, operative radiotherapy, hadron therapy, hpyerthermia, combined radio-chemo-therapy, biometric clinical studies, intensity modulated radiotherapy, side effects, oncological diagnostics; central nervous system and sense organs, head-neck carcinomas, breast cancer, thorax organs, esophagus carcinoma, stomach carcinoma, pancreas carcinoma, heptabiliary cancer and liver metastases, rectal carcinomas, kidney and urinary tract, prostate carcinoma, testicular carcinoma, female pelvis, lymphatic system carcinomas, soft tissue carcinoma, skin cancer, bone metastases, pediatric tumors, nonmalignant diseases, emergency in radio-oncology, supporting therapy, palliative therapy.

  18. State of accelerator for therapy

    Maruhashi, A

    2002-01-01

    21 facilities carry out particle radiotherapy in the world and 6 facilities will start in the next year. They are shown in the table. 6 facilities of them exist in Japan. Small accelerator for proton therapy is developed. The area of them becomes smaller than 100 m sup 2. 5 makers, form, kinds of accelerator, length of track, beam energy of them are shown. States of particle radiotherapy in 4 facilities in Japan are explained by the kinds of particle, energy, beam intensity, time structure and radiation room. The important problems are reconsideration of building and compact rotating gantry. The problems of radiotherapy are explained. (S.Y.)

  19. Accelerated split-course radiotherapy and simultaneous cis-dichlorodiammine-platinum and 5-fluorouracil chemotherapy with folinic acid enhancement for unresectable carcinoma of the head and neck

    Thirty-four (6 stage III, 28 stage IV) patients with advanced squamous cell carcinoma of the head and neck were treated by simultaneous radio-chemotherapy. Treatment was divided into three cycles. Chemotherapy consisted of cis-diamminedichloroplatinum(II) (cis-DDP) 60 mg/sqm i.v., 5-fluorouracil (5-FU) 350 mg/sqm i.v. and folinic acid (FA)-50 mg/sqm i.v. on day 2 and 5-FU 350 mg/sqm per 24 h and FA 100 mg/sqm/24 h on days 2-5. Radiotherapy consisted of 23.4 Gy/9 days divided in 13 fractions of 1.8 Gy delivered twice a day from day 3 through day 11. This regimen was repeated on days 22 and 44. Total radiation dose amounted to 70.2 Gy/51 days. Mean follow-up of surviving patients was 21 (14-34) months. 28/32 patients achieved complete response, 4/32 partial response. Actuarial one and two years survival were 88 and 58% including two early deaths from tumour bleeding. Local control rates at one and two years were 87 and 81%, respectively. This protocol produces excellent palliation and the chance of improved long term tumour control. Two patients developed distant metastases. Overall toxicity was tolerable. Since the treatment breaks were inserted after low radiation doses, acute mucositis healed rapidly and was not a limiting factor. 39 refs.; 3 figs.; 3 tabs

  20. Radiotherapy for recurrent breast cancer

    Clinico-radiobiological characteristics of radiotherapy for relapsed breast cancer were studied. Adequate choice of tissue mass to be exposed appeared much more important than any change in focal dose within 50-80 Gy, to achieve higher frequency of locoregional therapeutic effect. However, recurrent tumors more than 3 large lower radiosensitivity involving a sharp rise in the likelihood of dissemination. Radiotherapy for primary tumor did not affect the radiosensitivity of recurrent malignancies but slowed down the rate of its growth. Also, it might promote the dissemination acceleration

  1. Biological and medical research with accelerated heavy ions at the Bevalac, 1974--1977. [Planning for use for radiotherapy and as radiation source for diagnostic radiography

    Elam, S. (ed.)

    1977-04-01

    The Bevalac, a versatile high-energy heavy-ion accelerator complex, has been in operation for less than two years. A major purpose for which the Bevalac was constructed was to explore the possibility of heavy-ion teams for therapy for certain forms of cancer. Significant progress has been made in this direction. The National Cancer Institute has recognized the advantages that these and other accelerated particles offer, and heavy ions have been included in a long-term plan for particle therapy that will assess by means of controlled therapeutic tests the value of various modalities. Since accelerated heavy ions became available, the possibility of other contributions, not planned, became apparent. We are developig a new diagnostic method known as heavy-ion radiography that has greatly increased sensitivity for soft-tissue detail and that may become a powerful tool for localizing early tumors and metastases. We have discovered that radioactive beams are formed from fragmentation of stable deflected beams. Use of these autoradioactive beams is just beginning; however, we know that these beams will be helpful in localizing the region in the body where therapy is being delivered. In addition, it has been demonstrated that instant implantation of the radioactive beam allows direct measurements of blood perfusion rates in inaccessible parts of the body, and such a technique may become a new tool for the study of fast hot atom reactions in biochemistry, tracer biology and nuclear medicine. The Bevalac will also be useful for the continuation of previously developed methods for the control of acromegaly, Cushing's disease and, on a research basis, advanced diabetes mellitus with vascular disease. The ability to make small bloodless lesions in the brain and elsewhere with heavy-ion beams has great potential for nervous-system studies and perhaps later for radioneurosurgery.

  2. Cosmetic Outcomes for Accelerated Partial Breast Irradiation Before Surgical Excision of Early-Stage Breast Cancer Using Single-Dose Intraoperative Radiotherapy

    Purpose: Determine cosmetic outcome and toxicity profile of intraoperative radiation delivered before tumor excision for patients with early-stage breast cancer. Methods and Materials: Patients age 48 or older with ultrasound-visible invasive ductal cancers <3 cm and clinically negative lymph nodes were eligible for treatment on this institutional review board-approved Phase II clinical trial. Treatment planning ultrasound was used to select an electron energy and cone size sufficient to cover the tumor plus a 1.5- to 2.0-cm circumferential margin laterally and a 1-cm-deep margin with the 90% isodose line. The dose was prescribed to a nominal 15 Gy and delivered using a Mobetron electron irradiator before tumor excision by segmental mastectomy. Physician- and patient-assessed cosmetic outcome and patient satisfaction were determined by questionnaire. Results: From March 2003 to July 2007, 71 patients were treated with intraoperative radiation therapy. Of those, 56 patients were evaluable, with a median follow-up of 3.1 years (minimum 1 year). Physician and patient assessment of cosmesis was 'good or excellent' (Radiation Therapy Oncology Group cosmesis scale) in 45/56 (80%) and 32/42 (76%) of all patients, respectively. Eleven patients who received additional whole breast radiation had similar rates of good or excellent cosmesis: 40/48 (83%) and 29/36 (81%), respectively). Grade 1 or 2 acute toxicities were seen in 4/71 (6%) patients. No Grade 3 or 4 toxicities or serious adverse events have been seen. Conclusion: Intraoperative radiotherapy delivered to an in situ tumor is feasible with acceptable acute tolerance. Patient and physician assessment of the cosmetic outcome is good to excellent.

  3. Accelerated intensity-modulated radiotherapy plus temozolomide in patients with glioblastoma. A phase I dose-escalation study (ISIDE-BT-1)

    We performed a dose-escalation trial to determine the maximum tolerated dose (MTD) of intensity-modulated radiotherapy (IMRT) with standard concurrent and sequential-dose temozolomide (TMZ) in patients with glioblastoma multiforme. Histologically proven glioblastoma patients underwent IMRT dose escalation. IMRT was delivered over 5 weeks with the simultaneous integrated boost (SIB) technique to the two planning target volumes (PTVs) defined by adding 5-mm margin to the respective clinical target volumes (CTVs). CTV1 was the tumor bed plus the enhancing lesion with 10-mm margin; CTV2 was the area of perifocal edema with 20-mm margin. Only the PTV1 dose was escalated (planned dose escalation: 60, 62.5, 65, 67.5, 70 Gy) while the PTV2 dose remained the same (45 Gy). Forty consecutive glioblastoma patients were treated. While no dose-limiting toxicity (DLT) was recorded during the dose escalation up to 67.5/2.7 Gy, two out of the first six consecutively enrolled patients on the highest dose level (70/2.8 Gy) experienced a DLT, and therefore a cohort expansion was required. 3/14 patients experienced a DLT on the highest planned dose level, and therefore the MTD was not exceeded. After a median follow-up time of 25 months no grade >2 late neurological toxicity was recorded. By using a SIB IMRT technique, a radiation dose of 70 Gy in 25 fractions (biological effective dose-BED-of 92.8 Gy) can be delivered with concurrent and sequential standard dose TMZ, without unacceptable acute toxicity in patients with glioblastoma. (author)

  4. Five-Year Results From a Scandinavian Sarcoma Group Study (SSG XIII) of Adjuvant Chemotherapy Combined With Accelerated Radiotherapy in High-Risk Soft Tissue Sarcoma of Extremities and Trunk Wall

    Jebsen, Nina L. [Department of Surgical Sciences, University of Bergen Faculty of Medicine, Bergen, Norway and Department of Oncology, Haukeland University Hospital, Bergen (Norway); Bruland, Oyvind S. [Cancer Clinic, Norwegian Radium Hospital, Oslo University Hospital and University of Oslo Faculty Division, Clinical Medicine, Oslo (Norway); Eriksson, Mikael; Engellau, Jacob [Department of Oncology, Skane University Hospital, Lund (Sweden); Turesson, Ingela [Department of Oncology, Uppsala University Hospital, Uppsala (Sweden); Folin, Annika [Department of Oncology, Karolinska Hospital, Stockholm (Sweden); Trovik, Clement S. [Departments of Oncology and of Orthopedics, Haukeland University Hospital, Bergen (Norway); Hall, Kirsten Sundby [Cancer Clinic, Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway)

    2011-12-01

    Purpose: To evaluate adjuvant chemotherapy and interpolated accelerated radiotherapy (RT) for adult patients with high-risk soft tissue sarcoma in the extremities or trunk wall. Methods and Materials: High-risk soft tissue sarcoma was defined as high-grade malignancy and at least two of the following criteria: size {>=}8 cm, vascular invasion, or necrosis. Six cycles of doxorubicin and ifosfamide were prescribed for all patients. RT to a total dose of 36 Gy (1.8 Gy twice daily) was inserted between two chemotherapy cycles after marginal margin resection regardless of tumor depth or after wide-margin resection for deep-seated tumors. RT was boosted to 45 Gy in a split-course design in the case of intralesional margin resection. Results: A total of 119 patients were eligible, with a median follow-up of 5 years. The 5-year estimate of the local recurrence, metastasis-free survival, and overall survival rate was 12%, 59%, and 68%, respectively. The group receiving RT to 36 Gy had a local recurrence rate of 10%. In contrast, the local recurrence rate was 29% in the group treated with RT to 45 Gy. The presence of vascular invasion and low chemotherapy dose intensity had a negative effect on metastasis-free and overall survival. Toxicity was moderate after both the chemotherapy and the RT. Conclusions: Accelerated RT interposed between chemotherapy cycles in a selected population of patients with high-risk soft tissue sarcoma resulted in good local and distant disease control, with acceptable treatment-related morbidity. The greater radiation dose administered after intralesional surgery was not sufficient to compensate for the poorer surgical margin. Vascular invasion was the most important prognostic factor for metastasis-free and overall survival.

  5. Five-Year Results From a Scandinavian Sarcoma Group Study (SSG XIII) of Adjuvant Chemotherapy Combined With Accelerated Radiotherapy in High-Risk Soft Tissue Sarcoma of Extremities and Trunk Wall

    Purpose: To evaluate adjuvant chemotherapy and interpolated accelerated radiotherapy (RT) for adult patients with high-risk soft tissue sarcoma in the extremities or trunk wall. Methods and Materials: High-risk soft tissue sarcoma was defined as high-grade malignancy and at least two of the following criteria: size ≥8 cm, vascular invasion, or necrosis. Six cycles of doxorubicin and ifosfamide were prescribed for all patients. RT to a total dose of 36 Gy (1.8 Gy twice daily) was inserted between two chemotherapy cycles after marginal margin resection regardless of tumor depth or after wide-margin resection for deep-seated tumors. RT was boosted to 45 Gy in a split-course design in the case of intralesional margin resection. Results: A total of 119 patients were eligible, with a median follow-up of 5 years. The 5-year estimate of the local recurrence, metastasis-free survival, and overall survival rate was 12%, 59%, and 68%, respectively. The group receiving RT to 36 Gy had a local recurrence rate of 10%. In contrast, the local recurrence rate was 29% in the group treated with RT to 45 Gy. The presence of vascular invasion and low chemotherapy dose intensity had a negative effect on metastasis-free and overall survival. Toxicity was moderate after both the chemotherapy and the RT. Conclusions: Accelerated RT interposed between chemotherapy cycles in a selected population of patients with high-risk soft tissue sarcoma resulted in good local and distant disease control, with acceptable treatment-related morbidity. The greater radiation dose administered after intralesional surgery was not sufficient to compensate for the poorer surgical margin. Vascular invasion was the most important prognostic factor for metastasis-free and overall survival.

  6. Efficacy of intensified hyperfractionated and accelerated radiotherapy and concurrent chemotherapy with carboplatin and 5-fluorouracil: Updated results of a randomized multicentric trial in advanced head-and-neck cancer

    Purpose: To prove an expected benefit of concurrent radiochemotherapy (RCT), a two-arm randomized multicentric study was performed. In a subgroup analysis the influence of pretherapeutical hemoglobin level (p-Hb) on survival under locoregional control (SLC) was tested. Patients and Methods: The study included primarily untreated Stage III/IV (International Union Against Cancer [UICC]) oropharyngeal and hypopharyngeal carcinomas. Patients were randomized to receive either hyperfractionated (hf) and accelerated (acc) RCT with two cycles 5-fluorouracil (600 mg/m2/day) and carboplatin (70 mg/m2/day) on Days 1-5 and 29-33 or hf-acc radiotherapy (RT) alone. Total RT dose in both arms was 69.9 Gy in 38 days in concomitant boost technique. Results: After a median follow-up time of 57 months, SLC is significantly better in RCT than in RT (p = 0.01), with median SLC of 17 months and 11 months, respectively. Also overall survival (OS) shows a benefit for RCT (p 0.016), with a median survival of 23 months for RCT and 16 months for RT. However, the benefit in SLC and OS is not seen in hypopharyngeal carcinomas. In a multivariate analysis of oropharyngeal cancer patients, p-Hb levels lower than 12.7 g/dL resulted in lower SLC compared with higher p-Hb levels up to 13.8 g/dL. P-Hb levels >13.8 g/dL did not further improve SLC. Conclusions: Hyperfractionated-accelerated RCT is superior to hf-acc RT in oropharyngeal carcinomas. P-Hb levels >13.8 g/dL do not further improve SLC

  7. Natural history of intracranial meningioma after radiotherapy

    The author examined the natural history of intracranial meningioma after radiotherapy using CT or MR imaging. Twenty patients with intracranial meningioma received radiotherapy from a high-energy linear accelerator (4-10 MV X rays) from 1980 to 1996. The total doses were 50 Gy to the tumor bed in single doses of 2 Gy in 5 weekly fractions. Meningiomas in 10 of 20 patients were reduced within 1 to 38 months after radiotherapy, the average being 11 months. The tumors were controlled for a median of 60 months after radiotherapy (range 19-126 months). Four other patients have shown no change in tumor size after radiotherapy. The tumors were controlled for a median of 70 months after radiotherapy (range 37-127 months). The other six patients have shown tumor growth within 3 to 25 months after radiotherapy, after which the tumors stopped growing for a median of 71 months (range 2-181 months). Neither tumor size nor histological type was related to response. The growth of tumors was controlled by radiotherapy for a median duration of 43 months in the meningothelial type, 52 months in the fibroblastic type, and 61 months in the transitional type. The median duration for all benign tumors was 52 months. A moderate correlation was noted between tumor response and functional outcome after radiotherapy in 9 patients with neurological deficits. The natural histories of intracranial meningiomas after radiotherapy were grouped into three categories. Some tumors showed no change in size over a long period. This was a characteristic response after radiotherapy that differed from that of other brain tumors. The results of this study provide important information for the follow-up of intracranial meningiomas after radiotherapy. (author)

  8. Accelerated radiotherapy and concomitant high dose chemotherapy in non resectable stage IV locally advanced HNSCC: Results of a GORTEC randomized trial

    Background: The objective was to evaluate the efficacy of a strong increase of the dose-intensity of concomitant radio-chemotherapy (RT-CT) in patients with far advanced non metastatic HNSCC. Methods: Eligible patients had N3 disease (UICC 1997) and the primary tumor and/or the node(s) had to be strictly unresectable. Patients with palpable N2B-C were also eligible if massive nodal involvement was present. 109 patients were included, with 53 randomized to RT-CT and 56 to accelerated RT. In the RT-CT arm, the RT regimen consisted of 64 Gy in 5 weeks and the CT regimen consisted of synchronous CDDP 100 mg/m2 on days 2, 16, and 30 and 5FU 1000 mg/m2 on days1-5 and 29-33 of the RT course. After RT-CT, two adjuvant cycles of CDDP-5FU were delivered in good responders. A control arm was using a very accelerated RT, delivering 64 Gy in 3 weeks. Results: The most common tumor sites were oropharynx and hypopharynx. Most of the patients had T4 disease (70%) and 100% had a massive nodal involvement (mainly N3 with a mean nodal size >7 cm in both arms). A significant difference was observed in favor of the RT-CT arm (p = 0.005) in terms of cumulative incidence of local regional failure or distant metastases. However, the overall survival and event free survival rates were not significantly different between the two arms (p = 0.70 and 0.16, respectively). The lack of survival benefit in favor of the RT-CT was partly due to an excess of initial early treatment related death in the RT-CT arm. Conclusion: The very intense RT-CT schedule was more efficient on disease control, but was also more toxic than accelerated RT alone, pointing out that there was no clear improvement of the therapeutic index. This study shows the limits of dose-intensification, with regard to concomitant RT-CT.

  9. Feasibility Study of Moderately Accelerated Intensity-Modulated Radiotherapy Plus Concurrent Weekly Cisplatin After Induction Chemotherapy in Locally Advanced Head-and Neck Cancer

    Purpose: To evaluate the feasibility and efficacy of moderately accelerated intensity-modulated radiation therapy (IMRT) along with weekly cisplatin, after induction chemotherapy, in patients with locally advanced unresectable head and neck cancer (HNC). Methods and Materials: Patients with Stage III or IV locally advanced HNC, without progressive disease after three courses of induction chemotherapy, received concurrent chemo-IMRT (weekly cisplatin 30 mg/m2 plus simultaneous integrated boost IMRT). A total of 67.5 Gy in 30 fractions were delivered to primary tumor and involved nodes, 60 Gy in 30 fractions to high-risk nodal areas, and 55.5 Gy in 30 fractions to low-risk nodal areas. Results: In all, 36 patients (median age, 56 years) with International Union Against Cancer (UICC) Stage III (n = 5) and IV (n = 31) were included. Of the 36 patients, 17 had received CF (cisplatin and 5-fluorouracil (CF) and 19 had received docetaxel cisplatin and 5-fluorouracil (DCF). During concurrent chemoradiation, 11 of 36 patients (30.5%) experienced Grade III mucositis (CF, 47%; DCF, 15%; p < 0.04). Grade III pharyngeal-esophageal toxicity was observed in 5 of 19 patients (26.3%; CF, 0.0%; DCF, 26.3%; p = 0.02). Two patients died of complications (5.5%). After chemoradiation, the complete response rate was 63.8%. Two-year local control was 88.7%. Two-year progression free survival and overall survival were 74.5% and 60.9%, respectively. Conclusions: In our experience, a moderately accelerated chemo-IMRT was feasible after induction chemotherapy. However, a noteworthy early death rate of 5.5% was observed. Intensive supportive care strategies should be defined to better manage radiation-induced toxic effects. Longer follow-up is required to determine the incidence of late radiation toxicities and tumor control rates.

  10. Continuous accelerated 7-days-a-week radiotherapy for head-and-neck cancer: Long-term results of Phase III clinical trial

    Purpose: To update 5-year results of a previously published study on special 7-days-a-week fractionation continuous accelerated irradiation (CAIR) for head-and-neck cancer patients. Methods and Materials: One hundred patients with squamous cell carcinoma of head and neck in Stage T2-4N0-1M were randomized between two definitive radiation treatments: accelerated fractionation 7 days a week including weekends (CAIR) and conventional 5 days a week (control). Hence the overall treatment time was 2 weeks shorter in CAIR. Results: Five-year local tumor control was 75% in the CAIR group and 33% in the control arm (p < 0.00004). Tumor-cure benefit corresponded with significant improvement in disease-free survival and overall survival rates. Confluent mucositis was the main acute toxicity, with the incidence significantly higher in CAIR patients than in control (respectively, 94% vs. 53%). When 2.0-Gy fractions were used, radiation necrosis developed in 5 patients (22%) in the CAIR group as a consequential late effect (CLE), but when fraction size was reduced to 1.8 Gy no more CLE occurred. Actuarial 5-year morbidity-free survival rate was similar for both treatments. Conclusions: Selected head-and-neck cancer patients could be treated very effectively with 7-days-a-week radiation schedule with no compromise of total dose and with slight 10% reduction of fraction dose (2 Gy-1.8 Gy), which article gives 1 week reduction of overall treatment time compared with standard 70 Gy in 35 fractions over 47-49 days. Although this report is based on the relatively small group of patients, its results have encouraged us to use CAIR fractionation in a standard radiation treatment for moderately advanced head-and-neck cancer patients

  11. Palliative Radiotherapy

    Palliative care does not attempt to prolong survival but to the achieve the highest quality of life both for the patient and their family covering their physical, psychological, social and spiritual needs. Radiotherapy (RT), one of the most important therapeutic modalities, has a great significance in palliative medicine for cancer since it attempts to reduce as much as possible the acute reaction associated with the treatment for the patient. (Author)

  12. Dosimetric comparison on tissue interfaces with TLD dosimeters, L-alanine, EDR2 films and Penelope simulation for a Co-60 source and linear accelerator in radiotherapy

    Percentage depth dose curves were obtained with TLD-100 dosimeters, EDR2 films and Penelope simulation at the interfaces in an inhomogeneous mannequin, composed by equivalent materials to the human body built for this study, consisting of cylindrical plates of solid water-bone-lung-bone-solid water of 15 cm in diameter and 1 cm in height; plates were placed in descending way (4-2-8-2-4). Irradiated with Co-60 source (Theratron Equinox-100) for small radiation fields 3 x 3 cm2 and 1 x 1 cm2 at a surface source distance of 100 cm from mannequin. The TLD-100 dosimeters were placed in the center of each plate of mannequin irradiated at 10 Gy. The results were compared between these measurement techniques, giving good agreement in interfaces better than 97%. This study was compared with the same characteristics of another study realized with other equivalent materials to human body not homogeneous acrylic-bone-cork-bone-acrylic. The percentage depth dose curves were obtained with mini-dosimeters L-alanine of 1 mm in diameter and 3 mm in height and 3.5 to 4.0 mg of mass with spectrometer band K (EPR). The mini-dosimeters were irradiated with a lineal accelerator PRIMUS Siemens 6 MV. The results of percentage depth dose of L-alanine mini-dosimeters show a good agreement with the percentage depth dose curves of Penelope code, better than 97.7% in interfaces of tissues. (Author)

  13. Linear Correlation Between Patient Survival and Decreased Percentage of Tumor [18F]Fluorodeoxyglucose Uptake for Late-Course Accelerated Hyperfractionated Radiotherapy for Esophageal Cancer

    Purpose: The aims of this trial were to study whether a decreased percentage of tumor fluorodeoxyglucose (FDG) uptake (%DeltaSUVmax) correlated with overall survival and local control times for patients with esophageal cancer and which patients would benefit from a late-course accelerated hyperfractionated (LCHF) radiation scheme. Methods and Materials: A total of 50 eligible patients with squamous esophageal cancer received positron-emission tomography examinations three times and were treated with the LCHF radiation scheme, with a dose of 68.4 Gy/41 fractions in 6.5 weeks. A %DeltaSUVmax value was calculated, and patients were stratified as highly radiosensitive (HR), moderately radiosensitive (MR), and low radiosensitivity (LR) according to %DeltaSUVmax values in the conventional fraction (CF) scheme. Then, a linear correlation was calculated between patients’ survival time and %DeltaSUVmax. Local control and overall survival rates were compared after stratification. Results: In the MR subgroup, there was no linear correlation between %DeltaSUVmax and the CF and LCHF schemes (correlation coefficient, R 0.05). In the other subgroups (HR and LR), %DeltaSUVmax values between the CF and LCHF schemes were correlated. Also, in the HR and LR subgroups, %DeltaSUVmax after radiation correlated with overall survival or local control rates (correlation coefficient, R >0.5, and p < 0.05). Three-year local control rates in the HR, MR, and LR subgroups were 100%, 81.5%, and 0%, respectively (p < 0.001). Also, 3-year overall survival rates were 92.4%, 58.8%, and 0% for HR, MR, and LR subgroups, respectively (p < 0.001). Conclusions: Postradiation %DeltaSUVmax was positively correlated with survival time for patients’ with esophageal cancer. Patients who benefited from LCHF schedules were those with a decrease of 30% to 60% in tumor FDG uptake after the completion of CF radiation.

  14. Quality assurance (QA) and implementation of intensity modulated radiotherapy (IMRT) with dynamic multileaf collimator (DMLC) on 2100 C/D linear accelerator

    Intensity Modulated Radiation Therapy (IMRT) involves the modulation of radiation beam intensities in order to conform the target volumes and spare surrounding critical structures and normal tissues. IMRT can improve the dose distribution to a large extent compared to conventional 3DCRT. The purpose of this article is to discuss the methodology adopted in the Quality Assurance (QA) program for the implementation of IMRT on 2100 C/D linear accelerator at our center. QA of Multi-Leaf Collimator (MLC) including mechanical tests, radiation tests, dynamic MLC tests and patient specific QA of the final IMRT plan has been described here in detail. The average transmission values were found to be 1.31% and 1.40% for A bank and B bank, respectively, for 6 MV photon beam measured with the parallel plate chamber. From film measurements we got the maximum interleaf transmission value of 1.88%. The speed of the MLC leaves was found to be within the specification of the manufacturer. The MLC positional accuracy with the methods mentioned gave a precision of 1 mm, irrespective of the gantry positions. The absolute dose for 6 and 15 MV photons was estimated for the Dynamic MLC (DMLC) field periodically and was found to be consistent. The inverse-planning algorithm produced satisfactory dose distribution and adequate Planning Target Volume (PTV) coverage with critical organ dose-volume parameters, within the respective tolerances. The percentage deviation between the measured and the calculated absolute dose for the Intensity Modulated (IM) fields is found to be less than 3%. The clinical implementation of inverse planning and treatment delivery with DMLC is extremely complex and involves a substantial developmental effort. The dose delivery in DMLC mode needs a confirmation using established QA program that is both stringent and efficient. However, a comprehensive QA is mandatory to ensure the safe and accurate dose delivery. (author)

  15. Postmastectomy radiotherapy

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  16. Experimental radiotherapy and clinical radiobiology. Vol. 20. Proceedings

    The proceedings include contributions on the following issues: laser driven proton accelerators on the way for radiotherapy, radiobiological evaluation of new radiations; molecular factors of radiation response; biological targeting; EGFR epidermal growth factor receptor/targeting - combined internal and external irradiation, radiobiology of normal tissues; dose-volume histograms for the radiotherapy: curves without radiobiological relevance or important information for the therapy planning; HPV (human papilloma virus) and radiation sensitivity of HNSCC (head and neck squamous cell carcinomas): evidence, radiobiological mechanism, clinical consequences and perspectives; mechanisms of action and intertumoral heterogeneity of response to EGFR inhibition in radiotherapy of solid tumors; evaluation of biomarkers for radiotherapy.

  17. The development of radiotherapy in Slovenia

    The historical data on the development of radiotherapy in Slovenia are presented from its first use in this county in 1902 until the present. The Institute of Oncology in Ljubljana was established in 1938 with the intention of providing a sound development of radium and roentgen cancer treatment. After World War II, the development of radiotherapy was dynamic, which is evident from the data on new radiation sources in external beam therapy (accelerators, telecobalt units), in brachytherapy (various sealed radioisotopes) as well as in the introduction of therapy with unsealed radioisotopes. In 1947, a Chair of Oncology and Radiotherapy was instituted at the Medical Faculty of the University of Ljubljana (with the seat at the Institute of Oncology). In 1955, radiotherapy and oncology were officially recognized as separate branches of medicine requiring special obligatory postgraduate residency training. Within the Medical Society of Slovenia, the Section for Radiotherapy was established in 1987. The following year, the Section for Radiotherapy of Slovenia became a member of the European Society for Therapeutic Radiology and Oncology. Considering the size of population of Slovenia (nearly 2 million), it was reasonable that by this time radiotherapy became almost completely concentrated in one central institution, the Institute of Oncology, whose core and cohesive activity were represented in the multidisciplinary cancer treatment approach

  18. Palliative radiotherapy in developing countries

    Full text: The International Agency for Research on Cancer predicts that cancer incidence in developing countries will increase dramatically in the first two decades of this millennium. Already some 80% of cancer patients in developing countries present with incurable disease. [n many cases pain is a severe problem and palliation is needed to improve quality of life as well as extending survival. This paper will consider the physical and clinical aspects of palliative radiotherapy (PRT), choice of radiation modality, alternative approaches to imaging and therapy and cost-benefit considerations. The potential benefits of a dedicated palliative centre include lower cost and therefore more centres, enabling more patients access to regional palliative care. Whilst there is an obvious need for palliative radiotherapy, simple curative treatments could also be managed. C060 radiotherapy has important advantages in developing countries, because of the higher initial cost of a linear accelerator, as well as the need for reliable power supply and the level of skill required by linac technicians and physicists. The beam characteristics of both C060 units and low energy linacs are compared and both are found to be acceptable for palliation. The concept of telemedicine is also discussed, using mobile phones and internet communication to allow rural clinics to receive support from specialists based in the cities, to send images for remote diagnosis and remote dose planning for radiotherapy. (author)

  19. High-energy accelerators in medicine

    Mandrillon, Pierre

    1992-01-01

    The treatment of tumours with charged particles, ranging from protons to "light ions" ( Carbon, Oxygen, Neon) has many advantages, but up to now has been little used because of the absence of facilities. After the successful pioneering work carried out with accelerators built for physics research, machines dedicated to this new radiotherapy are planned or already in construction. The rationale for this new radiotherapy, the high energy accelerators and the beam delivery systems are presented in these two lectures.

  20. Overview of radiotherapy resources in Beijing in 2010

    Objective: To investigate and analyze the resources of radiotherapy in Beijing, in order to provide reference for the subject development, resources allocation and professional training of radiotherapy. Methods: A questionnaire survey was conducted by on-site inspection, supplemented by telephone or e-mail investigation among the 33 hospitals with radiotherapy facilities to know the current status of distribution of radiotherapy institutions, radiotherapy facilities, human resources and number of patients treated. Results: There were 52 linear accelerators, 1 spiral CT machine, and 2 intraoperative radiotherapy machines in these 33 hospitals up to June 2010. Three-dimensional conformal or stereotactic radiotherapy was carried out in 31 hospitals, intensity modulated radiation therapy (IMRT) in 19, image guided radiation therapy (IGRT) in 6, and volumetric modulated arc therapy (VMRT) in 2. The number of professional personnel (except nurses) was 495, including 214 radiation oncologists, 78 radiotherapy physicists, and 203 radiotherapy technologists, and those with senior professional titles accounted for 52.3%, 17.9%, and 1.5%, respectively. Conclusions: Compared to the national level, the radiotherapy resources level is higher in Beijing, but the distribution of resources is imbalanced. The resource allocation should be optimized and training of the personnel should be strengthened so as to meet the growing needs of patients. (authors)

  1. Radiotherapy in paediatric oncology

    Full text: Radiation therapy has always been one of the most powerful tools in the fight against childhood cancer. Since the middle of the last century, we have known that most paediatric tumours are exquisitely sensitive to radiation. The early application of radiotherapy alone led to the first cures of retinoblastoma, Hodgkin lymphoma, as well as certain sarcomas and brain tumours. The generous application of radiation in conjunction with chemotherapy led to further extraordinary increases in survival rates for leukemias, Wilms tumour, sarcomas, and other paediatric malignancies. Over the past 40 years, the overall cure rate for childhood cancer has climbed from 25% to 75% in the USA. With this success, however, came the knowledge that radiation can be associated with significant late effects. We now have a much better understanding of both the benefits and risks of using radiation to treat children as we seek to optimize and refine its role in curative therapy. Leukemias constitute approximately one third of paediatric cancer diagnoses and most of these patients are successfully treated with chemotherapy alone. Central nervous system (CNS) radiation is still recommended for patients at highest risk of CNS failure and total body radiation is useful for the small percentage of patients who require bone marrow transplant. Brain tumours also make up almost one-third of paediatric neoplasms and children with most kinds of brain tumours will require high dose radiotherapy. Many of the other types of paediatric tumours (Wilms, neuroblastoma, sarcomas, etc.) also require radiotherapy as part of curative treatment. There have been considerable advances in radiation technology including three dimensional planning, intensity modulated radiation therapy, and protons. Individual paediatric patients may or may not benefit from advanced technologies based on numerous patient and disease related factors. Examples will be illustrated. We must also be mindful of economic and

  2. Status of Radiotherapy in Kenya: The Milestones and Challenges

    According to Gobacan 2012, seventy eight (78) Kenyans die daily of cancer related complications. Ratiotherapy is the treatment of cancer using high energy radiation targeting the tumour cells. The three main modalities used in treatment are radiotherapy, chemotherapy and surgery. More than 50% of cases are treated using radiotherapy. Radiotherapy is divided into two brad categoeis, namely external beam radiotherapy (EBRT) or teletherapy and internal radiotherapy (Brachytherapy). In Kenya, the machines available for EBRT are Cobalt-60 and linear accelerators. Co-60 source emits gamma-ray with energy of 1.25 MV while linear accelerators available locally emit photons (x-rays) and electrons ranging between 6 to 8MV. Until 2010, there was only one (public) radiotherapy facility using the co-60. Currently, four private facilities using linear accelerations have joined the fray. Two more public institutions are at different stages of putting up radiotherapy facilities. Owing to the high energy range, a lot of radiation safety considerations are made prior to installation, during acceptance testing and commissioning and during the operation. These include, but not limited to shielding integrity checks, Dosimetry checks, mechanical checks and emergency procedures check. In view of these, a lot of capacity building still needs to be done in term of skilled staff development as well as equipment

  3. The application of accelerator for medical therapy in Indonesia

    The study of the application of accelerator for medical therapy in Indonesia was carried out. Accelerator that used for therapy is an electron lintier accelerator (Linac) which can radiate electron beam and X-ray. This study shows that there are 8 unit of Linac distributed at 6 big hospitals in Indonesia, especially in Jakarta. This study also shows that radiotherapy facilities in Indonesia is un sufficient of. Therefore, providing radiotherapy facilities for hospitals, especially the big hospitals in Indonesia is necessary

  4. Project of compact accelerator for cancer proton therapy

    The status of the sub-projetc 'Compact Accelerator' in the framework of the Hadrontherapy Project leaded by Prof. Amaldi is described. Emphasis is given to the reasons of the use of protons for radiotherapy applications, to the results of the preliminary design studies of four types of accelerators as possible radiotherapy dedicated 'Compact Accelerator' and to the scenario of the fonts of financial resources

  5. Present status of radiotherapy in Venezuela

    The purpose of the work was to discover the conditions obtaining in the practice of radiotherapy in Venezuela; 15 public radiotherapy centres were visited, evaluated and information obtained on physical environment, treatment units, intracavitary radiotherapy groups, medical and para-medical personnel, recording of clinical data and number of patients. In the groups it was observed that: only one of 17 voltage stabilizing units was operating; the four linear accelerators can only be operated irregularly and there are 17 60Co units operating, but the majority of those are antiquated and worn out. One centre has a simulator and another has a computer. In intracavitary radiotherapy, approximately 50% of the centres do not carry out utero-vaginal implants in proper conditions. There are sufficient radiotherapists, but their working conditions cannot be compared with those in developed countries. There is a lack of auxiliary personnel, radiation physicists and dosimetrists. There is no training for radiotherapy technicians and there are not enough of them. In 50% of the centres, no treatment plans are made; one-third do not have any devices for immobilization. Four hospitals do not use radiotherapy histories or treatment graphics, and in four institutions no tumour record is used. The conclusion is that oncological radiotherapy is not adequate in most of the centres and it is recommended that: the damaged equipment should be repaired; the 60Co units with inadequate source-axis distances should be replaced; new sources should be acquired for the equipment with source-axis distances of 80 cm; maintenance should be constant; simulators should be provided; damaged intracavitary radiotherapy equipment and sources should be replaced; the numbers and training of technical personnel should be increased; physicists and dosimetrists should be trained; a national radiation physics centre should be set up, and the recording of clinical information should be improved. (author)

  6. Radiotherapy for Hodgkin lymphoma

    Specht, Lena [Rigshospitalet Copenhagen Univ. (Denmark). Depts. of Oncology and Haematology; Yahalom, Joachim (eds.) [Memorial Sloan-Kettering Cancer, New York, NY (United States). Dept. of Radiation Oncology

    2011-07-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  7. Radiotherapy for Hodgkin lymphoma

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  8. Radiotherapy gel dosimetry

    In radiotherapy, the primary objective is to deliver a prescribed dose of radiation to a tumour or lesion within a patient while minimising the dose delivered to the surrounding healthy tissue. Traditional radiotherapy treatments usually involve simple external or internal irradiations of a tumour. External irradiations are normally achieved in the clinic with photon or electron beams produced by high energy linear accelerators. The photon or electron beams are collimated into regular shapes as they emerge from the treatment head of the unit which is supported by a gantry that can be rotated isocentrically to any position. A discrete number of photon or electron beams with different angles of incidence that intersect at the iso-centre are used to produce a region of high dose around the tumour volume (positioned at the iso-centre). Internal irradiations are normally achieved in the clinic by implanting radioactive sources in and around the tumour or lesion. Such irradiations are characterised by very high doses local to the tumour. Radioactive sources are also used to prevent post-angioplasty restenosis by inserting sources into arteries. Usually when treating a tumour, a compromise is made between tumour control and complications arising from normal tissue damage. One measure of this compromise, the therapeutic ratio, is defined as the radiation dose producing complications in 50% of patients divided by the dose providing tumour control in 50% of the patients. The therapeutic ratio depends on the radiobiological characteristics of the cancerous tissue and surrounding healthy tissues and on the radiation dose distribution achieved by the radiotherapy treatment. It is generally believed that the therapeutic ratio can be minimised by optimising the conformation of the radiation dose distribution to the target volume. This is difficult with traditional radiotherapy techniques since they do not produce dose distributions that adequately cover tumour volumes of complex

  9. Quality control programme for radiotherapy

    A 3 years pilot programme started in January 2000 with 33 philanthropic cancer institutions that provides medical services to 60% of the patients from the national social security system. Brazil has today 161 radiotherapy services (144 operating with megavoltage equipment). These 33 institutions are distributed over 19 Brazilian states. The aim of this programme is: To create conditions to allow the participants to apply the radiotherapy with quality and efficacy; To promote up dating courses for the physicians, physicists and technicians of these 33 Institutions. With the following objectives: To recommend dosimetric and radiological protection procedures in order to guarantee the tumor prescribed dose and safe working conditions; To help in establishing and implementing these procedures. The main activities are: local quality control evaluations, postal TLD audits in reference conditions, postal TLD audits in off axis conditions and training. The local quality control program has already evaluated 22 institutions with 43 machines (25 Co-60 and 18 linear accelerators). In these visits we perform dosimetric, electrical, mechanical and safety tests. As foreseen, we found more problems among the old Co-60 machines i.e., field flatness, size, symmetry and relative output factors; lasers positioning system alignment; optical distance indicator; radiation and light field coincidence; optical and mechanical distance indicators agreement, than among the linear accelerators i.e., field flatness and size; lasers positioning system alignment; tray interlocking and wedge filter factors

  10. Carbon-ion radiotherapy for marginal lymph node recurrences of cervical cancer after definitive radiotherapy: a case report

    Recurrences of cervical cancer after definitive radiotherapy often occur at common iliac or para-aortic lymph nodes as marginal lymph node recurrences. Patients with these recurrences have a chance of long-term survival by optimal re-treatment with radiotherapy. However, the re-irradiation often overlaps the initial and the secondary radiotherapy fields and can result in increased normal tissue toxicities in the bowels or the stomach. Carbon-ion radiotherapy, a form of particle beam radiotherapy using accelerated carbon ions, offers more conformal and sharp dose distribution than X-ray radiotherapy. Therefore, this approach enables the delivery of high radiation doses to the target while sparing its surrounding normal tissues. Marginal lymph node recurrences in common iliac lymph nodes after radiotherapy were treated successfully by carbon-ion radiotherapy in two patients. These two patients were initially treated with a combination of external beam radiotherapy and intracavitary and interstitial brachytherapy. However, the diseases recurred in the lymph nodes near the border of the initial radiotherapy fields after 22 months and 23 months. Because re-irradiation with X-ray radiotherapy may deliver high doses to a section of the bowels, carbon-ion radiotherapy was selected to treat the lymph node recurrences. A total dose of 48 Gy (RBE) in 12 fractions over 3 weeks was given to the lymph node recurrences, and the tumors disappeared completely with no severe acute toxicities. The two patients showed no evidence of disease for 75 months and 63 months after the initial radiotherapy and for 50 months and 37 months after the carbon-ion radiotherapy, respectively. No severe late adverse effects are observed in these patients. The two presented cases suggest that the highly conformal dose distribution of carbon-ion radiotherapy may be beneficial in the treatment of marginal lymph node recurrences after radiotherapy. In addition, the higher biological effect of carbon