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Sample records for accelerated radiation therapy

  1. Development of 6 MeV X-band accelerator for next generation radiation therapy

    We are developing a 6 MeV X-band accelerator for the next generation radiation therapy. This accelerator is a compact LINAC about the length 60 [cm] and accelerates electron beam of 100 [mA] and 6 [MeV] . The RF power source is a small magnetron with 1.5 – 2.0 [MW] output. Various computer simulations were used for the design of the accelerator. The accelerator parts were processed using super-precision lathe and were joined by brazing. In the experiment of the completed accelerator, the energy of 6 [MeV] and beam current of 100 [mA] were observed. The accelerator is attached on a robot manipulator for medical treatment machine. In order to be certified for as a medical equipment, various tests are presently being carried out now. In this paper we described the design and measurements of the X-band accelerator. (author)

  2. Accelerators for Cancer Therapy

    Lennox, Arlene J.

    2000-05-30

    The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

  3. Use of electron linear accelerators in medical radiation therapy: physical characteristics. Overview report No. 1

    1976-02-01

    This report presents an overview of the physical characteristics of electron linear accelerators used in medical radiation therapy. Particular attention is given to those physical characteristics and performance parameters that are related to delivery of a useful, properly controlled prescription dose of radiation to the patient or to delivery of a potentially harmful dose of radiation to the patient, machine operators, or others in the vicinity of the accelerator. The purpose of the study, of which this report is a part, was to provide a data base which will assist the Bureau of Radiological Health in evaluating the need for a performance standard for medical linear accelerators and the priority which should be assigned to such a standard should one be required. (auth)

  4. Accelerator and radiation physics

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  5. Particle in cell simulation of laser-accelerated proton beams for radiation therapy

    In this article we present the results of particle in cell (PIC) simulations of laser plasma interaction for proton acceleration for radiation therapy treatments. We show that under optimal interaction conditions protons can be accelerated up to relativistic energies of 300 MeV by a petawatt laser field. The proton acceleration is due to the dragging Coulomb force arising from charge separation induced by the ponderomotive pressure (light pressure) of high-intensity laser. The proton energy and phase space distribution functions obtained from the PIC simulations are used in the calculations of dose distributions using the GEANT Monte Carlo simulation code. Because of the broad energy and angular spectra of the protons, a compact particle selection and beam collimation system will be needed to generate small beams of polyenergetic protons for intensity modulated proton therapy

  6. Accelerators for therapy

    In the past decades circular and linear electron accelerators have been developed for clinical use in radiation therapy of tumors with the aim of achieving a high radiation dose in the tumor and as low as possible dose in the adjacent normal tissues. Today about one thousand accelerators are in medical use throughout the world and many hundred thousand patients are treated every day with accelerator-produced radiation. There exists, however, a large number of patients who cannot be treated satisfactorily in this way. New types of radiations such as neutrons, negative pions, protons and heavy ions were therefore tested recently. The clinical experience with these radiations and with new types of treatment procedures indicate that in future the use of a scanning beam of high energy protons might be optimal for the treatment of tumors. (orig.)

  7. Dosimetric comparison of three dimensional conformal radiation therapy versus intensity modulated radiation therapy in accelerated partial breast irradiation

    S Moorthy

    2016-01-01

    Full Text Available Aim of Study: Breast conserving surgery (BCS is the standard treatment for stage I and II breast cancer. Multiple studies have shown that recurrences after lumpectomy occur mainly in or near the tumor bed. Use of accelerated partial breast irradiation (APBI allows for significant reduction in the overall treatment time that results in increasing patient compliance and decreasing healthcare costs. We conducted a treatment planning study to evaluate the role of intensity modulated radiation therapy (IMRT with regards to three-dimensional conformal radiation therapy (3DCRT in APBI. Materials and Methods: Computed tomography planning data sets of 33 patients (20 right sided and 13 left sided with tumor size less than 3 cm and negative axillary lymph nodes were used for our study. Tumor location was upper outer, upper inner, central, lower inner, and lower outer quadrants in 10, 10, 5, 4 and 4 patients, respectively. Multiple 3DCRT and IMRT plans were created for each patient. Total dose of 38.5 Gy in 10 fractions were planned. Dosimetric analysis was done for the best 3DCRT and IMRT plans. Results: The target coverage has been achieved by both the methods but IMRT provided better coverage (P = 0.04 with improved conformity index (P = 0.01. Maximum doses were well controlled in IMRT to below 108% (P < 0.01. Heart V2 Gy (P < 0.01, lung V5 Gy (P = 0.01, lung V10 Gy (P = 0.02, contralateral breast V1 Gy (P < 0.01, contralateral lung V2 Gy (P < 0.01, and ipsilateral uninvolved breast (P < 0.01 doses were higher with 3DCRT compared to IMRT. Conclusion: Dosimetrically, IMRT–APBI provided best target coverage with less dose to normal tissues compared with 3DCRT-APBI.

  8. Treatment of nasopharyngeal carcinoma using simultaneous modulated accelerated radiation therapy via helical tomotherapy: a phase II study

    Du Lei

    2016-06-01

    Full Text Available The aim of the study was to evaluate short-term safety and efficacy of simultaneous modulated accelerated radiation therapy (SMART delivered via helical tomotherapy in patients with nasopharyngeal carcinoma (NPC.

  9. A comparison of robotic arm versus gantry linear accelerator stereotactic body radiation therapy for prostate cancer

    Avkshtol, Vladimir; Dong, Yanqun; Hayes, Shelly B; Hallman, Mark A; Price, Robert A; Sobczak, Mark L; Horwitz, Eric M; Zaorsky, Nicholas G

    2016-01-01

    Prostate cancer is the most prevalent cancer diagnosed in men in the United States besides skin cancer. Stereotactic body radiation therapy (SBRT; 6–15 Gy per fraction, up to 45 minutes per fraction, delivered in five fractions or less, over the course of approximately 2 weeks) is emerging as a popular treatment option for prostate cancer. The American Society for Radiation Oncology now recognizes SBRT for select low- and intermediate-risk prostate cancer patients. SBRT grew from the notion that high doses of radiation typical of brachytherapy could be delivered noninvasively using modern external-beam radiation therapy planning and delivery methods. SBRT is most commonly delivered using either a traditional gantry-mounted linear accelerator or a robotic arm-mounted linear accelerator. In this systematic review article, we compare and contrast the current clinical evidence supporting a gantry vs robotic arm SBRT for prostate cancer. The data for SBRT show encouraging and comparable results in terms of freedom from biochemical failure (>90% for low and intermediate risk at 5–7 years) and acute and late toxicity (cancer-specific mortality) cannot be compared, given the indolent course of low-risk prostate cancer. At this time, neither SBRT device is recommended over the other for all patients; however, gantry-based SBRT machines have the abilities of treating larger volumes with conventional fractionation, shorter treatment time per fraction (~15 minutes for gantry vs ~45 minutes for robotic arm), and the ability to achieve better plans among obese patients (since they are able to use energies >6 MV). Finally, SBRT (particularly on a gantry) may also be more cost-effective than conventionally fractionated external-beam radiation therapy. Randomized controlled trials of SBRT using both technologies are underway. PMID:27574585

  10. Radiation therapy with laser-driven accelerated particle beams: physical dosimetry and spatial dose distribution

    One of the main goals of the Munich Centre for Advanced Photonics (MAP) is the application of laser driven accelerated (LDA) particle beams for radiation therapy. Due to the unique acceleration process ultrashort particle pulses of high intensity (> 107 particles /cm2/ns) are generated, which makes online detection an ambitious task. So far, state of the art detection of laser accelerated ion pulses are non-electronic detectors like radiochromic films (RCF), imaging plates (IP) or nuclear track detectors (e.g. CR39). All these kind of detectors are offline detectors requiring several hours of processing time. For this reason they are not qualified for an application in radiation therapy where quantitative real time detection of the beam is an essential prerequisite. Therefore we are investigating pixel detectors for real time monitoring of LDA particle pulses. First tests of commercially available systems with 8-20 MeV protons are presented. For radiobiological experiments second generation Gafchromic films (EBT2) have been calibrated with protons of 12 and 20 MeV for a dose range of 0.3-10 Gy. Dose verification in proton irradiation of subcutaneous tumours in mice was successfully accomplished using these films.

  11. Radiation therapy with laser-driven accelerated particle beams: physical dosimetry and spatial dose distribution

    Reinhardt, Sabine; Assmann, Walter [Ludwig-Maximilians Universitaet Muenchen (Germany); Kneschaurek, Peter; Wilkens, Jan [MRI, Technische Universitaet Muenchen (Germany)

    2011-07-01

    One of the main goals of the Munich Centre for Advanced Photonics (MAP) is the application of laser driven accelerated (LDA) particle beams for radiation therapy. Due to the unique acceleration process ultrashort particle pulses of high intensity (> 10{sup 7} particles /cm{sup 2}/ns) are generated, which makes online detection an ambitious task. So far, state of the art detection of laser accelerated ion pulses are non-electronic detectors like radiochromic films (RCF), imaging plates (IP) or nuclear track detectors (e.g. CR39). All these kind of detectors are offline detectors requiring several hours of processing time. For this reason they are not qualified for an application in radiation therapy where quantitative real time detection of the beam is an essential prerequisite. Therefore we are investigating pixel detectors for real time monitoring of LDA particle pulses. First tests of commercially available systems with 8-20 MeV protons are presented. For radiobiological experiments second generation Gafchromic films (EBT2) have been calibrated with protons of 12 and 20 MeV for a dose range of 0.3-10 Gy. Dose verification in proton irradiation of subcutaneous tumours in mice was successfully accomplished using these films.

  12. Accelerated hypofractionated radiation therapy compared to conventionally fractionated radiation therapy for the treatment of inoperable non-small cell lung cancer

    Amini Arya

    2012-03-01

    Full Text Available Abstract Background While conventionally fractionated radiation therapy alone is an acceptable option for poor prognostic patients with unresectable stage III NSCLC, we hypothesized that accelerated hypofractionated radiotherapy will have similar efficacy without increasing toxicity. Methods This is a retrospective analysis of 300 patients diagnosed with stage III NSCLC treated between 1993 and 2009. Patients included in the study were medically or surgically inoperable, were free of metastatic disease at initial workup and did not receive concurrent chemotherapy. Patients were categorized into three groups. Group 1 received 45 Gy in 15 fractions over 3 weeks (Accelerated Radiotherapy (ACRT while group 2 received 60-63 Gy (Standard Radiation Therapy 1 (STRT1 and group 3 received > 63 Gy (Standard Radiation Therapy (STRT2. Results There were 119 (39.7% patients in the ACRT group, 90 (30.0% in STRT1 and 91 (30.3% in STRT2. More patients in the ACRT group had KPS ≤ 60 (p 5% (p = 0.002, and had stage 3B disease (p Conclusions Despite the limitations of a retrospective analysis, our experience of accelerated hypofractionated radiation therapy with 45 Gy in 15 fractions appears to be an acceptable treatment option for poor performance status patients with stage III inoperable tumors. Such a treatment regimen (or higher doses in 15 fractions should be prospectively evaluated using modern radiation technologies with the addition of sequential high dose chemotherapy in stage III NSCLC.

  13. Use of electron linear accelerators in medical radiation therapy. Overview report No. 1. physical characteristics. Technical report

    1974-09-01

    The report is the first of a series of four overview reports prepared during the course of study regarding the use of electron linear accelerators in radiation therapy. The purpose of the study was to provide a data base which will assist BRH to decide whether the development of a performance standard concerning the radiation safety of medical linear accelerators is necessary, and if so, the priority which should be assigned to such a standard. The purpose of this report is to present an overview of the physical characteristics of electron linear accelerators used in medical radiation therapy. Particular attention is given to those physical characteristics and performance parameters which are related to delivery of a useful properly controlled prescription dose of radiation to the patient and to delivery of a potentially harmful dose of radiation to the patient, machine operator or others in the vicinity of the accelerator. (GRA)

  14. Dosimetric comparison of three dimensional conformal radiation therapy versus intensity modulated radiation therapy in accelerated partial breast irradiation

    Moorthy, S; H S Elhateer; SKD Majumdar; Mohammed, S; Patnaik, R; Narayanamurty

    2016-01-01

    Aim of Study: Breast conserving surgery (BCS) is the standard treatment for stage I and II breast cancer. Multiple studies have shown that recurrences after lumpectomy occur mainly in or near the tumor bed. Use of accelerated partial breast irradiation (APBI) allows for significant reduction in the overall treatment time that results in increasing patient compliance and decreasing healthcare costs. We conducted a treatment planning study to evaluate the role of intensity modulated radiation t...

  15. Accelerated hypofractionated radiation therapy compared to conventionally fractionated radiation therapy for the treatment of inoperable non-small cell lung cancer

    While conventionally fractionated radiation therapy alone is an acceptable option for poor prognostic patients with unresectable stage III NSCLC, we hypothesized that accelerated hypofractionated radiotherapy will have similar efficacy without increasing toxicity. This is a retrospective analysis of 300 patients diagnosed with stage III NSCLC treated between 1993 and 2009. Patients included in the study were medically or surgically inoperable, were free of metastatic disease at initial workup and did not receive concurrent chemotherapy. Patients were categorized into three groups. Group 1 received 45 Gy in 15 fractions over 3 weeks (Accelerated Radiotherapy (ACRT)) while group 2 received 60-63 Gy (Standard Radiation Therapy 1 (STRT1)) and group 3 received > 63 Gy (Standard Radiation Therapy (STRT2)). There were 119 (39.7%) patients in the ACRT group, 90 (30.0%) in STRT1 and 91 (30.3%) in STRT2. More patients in the ACRT group had KPS ≤ 60 (p < 0.001), more commonly presented with weight loss > 5% (p = 0.002), and had stage 3B disease (p < 0.001). After adjusting for clinical variables, there were no differences in the radiation groups in terms of the patterns of local or distant tumor control or overall survival. Some benefit in relapse free survival was seen in the STRT1 group as compared to ACRT (HR = 0.65, p = 0.011). Acute toxicity profiles in the ACRT were significantly lower for grade ≥ 2 radiation dermatitis (p = 0.002), nausea/vomiting (p = 0.022), and weight loss during treatment (p = 0.020). Despite the limitations of a retrospective analysis, our experience of accelerated hypofractionated radiation therapy with 45 Gy in 15 fractions appears to be an acceptable treatment option for poor performance status patients with stage III inoperable tumors. Such a treatment regimen (or higher doses in 15 fractions) should be prospectively evaluated using modern radiation technologies with the addition of sequential high dose chemotherapy in stage III NSCLC

  16. Hadron accelerators in cancer therapy

    The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadrontherapy Project (the largest project of this type in Europe) is then described, with reference to both the National Centre for Oncological Hadrontherapy and the design of two types of compact proton accelerators aimed at introducing proton therapy in a large number of hospitals. Finally, the radiation protection requirements are discussed. (author)

  17. Enhanced regeneration response of laryngeal and hypopharyngeal mucosa with accelerated hyperfractionated radiation therapy for glottic cancers

    The course and severity of acute mucosal reactions in 22 patients with previously untreated T1-2N0 glottic cancers were compared between two treatment schedules with different dose intensities: accelerated hyperfractionated radiation therapy (AHF) and standard conventional fractionation radiation therapy (CF). AHF consisted of a twice-daily fractionation of 1.5 Gy 10 times weekly to a total dose of 66 Gy given in 30-40 (median, 33) days. For CF, the fractionation was 2 Gy five times weekly for a total dose of 66 Gy in 45-51 (median, 49) days. Both treatment schedules were well tolerated and no treatment interruptions were necessary. The mucosal reaction reached a peak score clearly earlier with AHF than CF and already demonstrated improvement in the final treatment week. In contrast, the reaction persisted with CF. It is suggested that damaged mucosal tissues with AHF can be effectively compensated by enhanced regeneration response due to an adequately high dose intensity, suggesting a possible tolerability advantage for AHF. (author)

  18. Advances in medical electron linear accelerator technologies and the development of a next generation robotic radiation therapy system

    Radiation therapy for cancer began in the early 20th century with X-ray tubes delivering a few hundred keV. Through the 1930's to 1940's, 2 MV Van de Graaff accelerators and Betatrons of 20 to 45 MeV were used for cancer treatment. In the mid 1950's, radiation therapy combined 4 to 8 MeV linear accelerators with several high power microwave magnetrons and klystrons working in the megawatt range that have been developed for radar applications during the second world war. Since then, the linear accelerator became the most commonly used technology for radiation therapy and nowadays, more than 8000 linear accelerators are contributing to the treatment of cancer worldwide. We present the development of a real-time 3D robotic radiation therapy system combined with a compact X-band linear accelerator for the early detection of deep seated, small tumors. The system utilizes multiple narrow high energy X-ray beams focused on the target tumor. Real-time positioning is achieved by non-invasive methods based on correlation models for tumor motion and respiratory signals. Emphasis is placed on the tumor motion which is used to control a robotic head with six degrees of freedom to fix the tumor in a certain spatial position. (author)

  19. The Quality Control of Intensity Modulated Radiation Therapy (IMRT) for ONCOR Siemens Linear Accelerators Using Film Dosimetry

    Intensity Modulated Radiation Therapy has made a significant progress in radiation therapy centers in recent years. In this method, each radiation beam is divided into many subfields that create a field with a modulated intensity. Considering the complexity of this method, the quality control for Intensity Modulated Radiation Therapy is a topic of interest for researchers. This article is about the various steps of planning and quality control of Siemens linear accelerators for Intensity Modulated Radiation Therapy, using film dosimetry. This article in addition to review of the techniques, discusses the details of experiments and possible sources of errors which are not mentioned in the protocols and other references. This project was carried out in Isfahan Milad hospital which has two Siemens ONCOR linear accelerators. Both accelerators are equipped with Multi-Leaf Collimators which enables us to perform Intensity Modulated Radiation Therapy delivery in the step-and-shoot method. The quality control consists of various experiments related to the sections of radiation therapy. In these experiments, the accuracy of some components such as treatment planning system, imaging device (CT), Multi-Leaf Collimators, control system of accelerator, and stability of the output are evaluated. The dose verification is performed using film dosimetry method. The films were KODAK-EDR2, which were calibrated before the experiments. One of the important steps is the comparison of the calculated dose with planning system and the measured dose in experiments. The results of the experiments in various steps have been acceptable according to the standard protocols. The calibration of Multi-Leaf Collimators and evaluation of the leakage through the leaves of Multi-Leaf Collimator was performed by using the film dosimetry and visual check. In comparison with calculated and measured dose, more that 80% of the points have to be in agreement within 3% of the value. In our experiments

  20. Intensity modulated radiation therapy using laser-accelerated protons: a Monte Carlo dosimetric study

    In this paper we present Monte Carlo studies of intensity modulated radiation therapy using laser-accelerated proton beams. Laser-accelerated protons coming out of a solid high-density target have broad energy and angular spectra leading to dose distributions that cannot be directly used for therapeutic applications. Through the introduction of a spectrometer-like particle selection system that delivers small pencil beams of protons with desired energy spectra it is feasible to use laser-accelerated protons for intensity modulated radiotherapy. The method presented in this paper is a three-dimensional modulation in which the proton energy spectrum and intensity of each individual beamlet are modulated to yield a homogeneous dose in both the longitudinal and lateral directions. As an evaluation of the efficacy of this method, it has been applied to two prostate cases using a variety of beam arrangements. We have performed a comparison study between intensity modulated photon plans and those for laser-accelerated protons. For identical beam arrangements and the same optimization parameters, proton plans exhibit superior coverage of the target and sparing of neighbouring critical structures. Dose-volume histogram analysis of the resulting dose distributions shows up to 50% reduction of dose to the critical structures. As the number of fields is decreased, the proton modality exhibits a better preservation of the optimization requirements on the target and critical structures. It is shown that for a two-beam arrangement (parallel-opposed) it is possible to achieve both superior target coverage with 5% dose inhomogeneity within the target and excellent sparing of surrounding tissue

  1. Radiation Therapy

    ... therapy. At this time, you will have a physical exam , talk about your medical history , and maybe have imaging tests . Your doctor or nurse will discuss external beam radiation therapy, its benefits and side effects, and ways you can care ...

  2. Very accelerated radiation therapy: preliminary results in locally unresectable head and neck carcinomas

    Purpose: To report preliminary results of a very accelerated radiation therapy Phase I/II trial in locally advanced head and squamous cell carcinomas (HNSCC). Methods and Materials: Between 01/92 and 06/93, 35 patients with an unresectable HNSCC were entered in this study. Thirty-two (91%) had Stage IV, and 3 had Stage III disease. The mean nodal diameter, in patients with clinically involved nodes (83%), was 6.3 cm. The median Karnovsky performance status was 70. The treatment consisted of a twice daily schedule (BID) giving 62 Gy in 20 days. Results: In all cases, confluent mucositis was observed, which started about day 15 and resolved within 6 to 10 weeks. Eighty percent of patients had enteral nutritional support. The nasogastric tube or gastrostomy was maintained in these patients for a mean duration of 51.8 days. Eighteen patients (53%) were hospitalized during the course of treatment due to a poor medical status or because they lived far from the center (mean 25 days). Nineteen patients (56%) (some of whom were initially in-patients) were hospitalized posttreatment for toxicity (mean 13 days). Five patients (15%) were never hospitalized. During the follow-up period, 12 local and/or regional failures were observed. The actuarial 18-month loco-regional control rate was 59% (95% confidence interval, 45-73%). Conclusions: The dramatic shortening of radiation therapy compared to conventional schedules in our series of very advanced HNSCC resulted in: (a) severe acute mucosal toxicity, which was manageable but required intensive nutritional support in all cases; and (b) high loco-regional response rates, strongly suggesting that the time factor is likely to be critical for tumor control in this type of cancer

  3. Postmastectomy Hypofractionated and Accelerated Radiation Therapy With (and Without) Subcutaneous Amifostine Cytoprotection

    Koukourakis, Michael I., E-mail: targ@her.forthnet.gr [Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis (Greece); Panteliadou, Marianthi; Abatzoglou, Ioannis M.; Sismanidou, Kyriaki [Department of Radiotherapy/Oncology, Democritus University of Thrace, Alexandroupolis (Greece); Sivridis, Efthimios; Giatromanolaki, Alexandra [Department of Pathology, Democritus University of Thrace, Alexandroupolis (Greece)

    2013-01-01

    Purpose: Postmastectomy radiation therapy (PMRT) provides major local control and survival benefits. More aggressive radiation therapy schemes may, however, be necessary in specific subgroups, provided they are safely administered. We report the tolerance and efficacy of a highly accelerated and hypofractionated regimen (HypoARC). Methods and Materials: One hundred twelve high-risk patients who had undergone mastectomy received 10 consecutive fractions of 3.5 Gy in 12 days (thoracic wall and axillary/supraclavicular areas). Two consecutive additional fractions of 4 Gy were given to the surgical scar area (electrons 8-10 MeV) and 1 3.5-Gy fraction to the axilla (in cases with extensive nodal involvement). A minimum follow-up of 24 months (median, 44 months) was allowed before analysis. Of 112 patients, 21 (18.7%) refused to receive amifostine, the remaining receiving tolerance-based individualized doses (500-1000 mg/day subcutaneously). Results: By use of a dose individualization algorithm, 68.1%, 11%, and 18.7% of patients received 1000 mg, 750 mg, and 500 mg/day of amifostine. Patchy moist skin desquamation outside and inside the booster fields was noted in 14 of 112 (12.5%) and 26 of 112 (23.2%) patients, respectively. No case of acute pneumonitis was recorded. High amifostine dose offered a significant skin protection. Within a median follow-up time of 44 months, moderate subcutaneous edema outside and within the booster thoracic area was noted in 5 of 112 (4.4%) and 8 of 112 (7.1%) cases, respectively. Intense asymptomatic radiographic findings of in field lung fibrosis were noted in 4 of 112 (3.6%) patients. Amifostine showed a significant protection against lung and soft tissue fibrosis. A 97% projected 5-year local relapse free survival and 84% 5-year disease-specific survival were recorded. Lack of steroid receptor expression, simple human epidermal growth factor 2 positivity, or triple negative phenotype defined higher metastasis rates but had no effect on

  4. Postmastectomy Hypofractionated and Accelerated Radiation Therapy With (and Without) Subcutaneous Amifostine Cytoprotection

    Purpose: Postmastectomy radiation therapy (PMRT) provides major local control and survival benefits. More aggressive radiation therapy schemes may, however, be necessary in specific subgroups, provided they are safely administered. We report the tolerance and efficacy of a highly accelerated and hypofractionated regimen (HypoARC). Methods and Materials: One hundred twelve high-risk patients who had undergone mastectomy received 10 consecutive fractions of 3.5 Gy in 12 days (thoracic wall and axillary/supraclavicular areas). Two consecutive additional fractions of 4 Gy were given to the surgical scar area (electrons 8-10 MeV) and 1 3.5-Gy fraction to the axilla (in cases with extensive nodal involvement). A minimum follow-up of 24 months (median, 44 months) was allowed before analysis. Of 112 patients, 21 (18.7%) refused to receive amifostine, the remaining receiving tolerance-based individualized doses (500-1000 mg/day subcutaneously). Results: By use of a dose individualization algorithm, 68.1%, 11%, and 18.7% of patients received 1000 mg, 750 mg, and 500 mg/day of amifostine. Patchy moist skin desquamation outside and inside the booster fields was noted in 14 of 112 (12.5%) and 26 of 112 (23.2%) patients, respectively. No case of acute pneumonitis was recorded. High amifostine dose offered a significant skin protection. Within a median follow-up time of 44 months, moderate subcutaneous edema outside and within the booster thoracic area was noted in 5 of 112 (4.4%) and 8 of 112 (7.1%) cases, respectively. Intense asymptomatic radiographic findings of in field lung fibrosis were noted in 4 of 112 (3.6%) patients. Amifostine showed a significant protection against lung and soft tissue fibrosis. A 97% projected 5-year local relapse free survival and 84% 5-year disease-specific survival were recorded. Lack of steroid receptor expression, simple human epidermal growth factor 2 positivity, or triple negative phenotype defined higher metastasis rates but had no effect on

  5. Promotion of high-quality treatment and uninterrupted service of radiation therapy linear accelerators

    The experience of operation of radiotherapy complex at Donetsk Antitumor Center showed that a number of calibration and dosimetry tests were an inevitable part of high-quality radiation treatment and timely prevention of inconsiderable disorders in the work of linear accelerators, therefore the engineering service of this equipment should consist of various specialists.

  6. Application of Failure Mode and Effects Analysis to Intraoperative Radiation Therapy Using Mobile Electron Linear Accelerators

    Purpose: Failure mode and effects analysis (FMEA) represents a prospective approach for risk assessment. A multidisciplinary working group of the Italian Association for Medical Physics applied FMEA to electron beam intraoperative radiation therapy (IORT) delivered using mobile linear accelerators, aiming at preventing accidental exposures to the patient. Methods and Materials: FMEA was applied to the IORT process, for the stages of the treatment delivery and verification, and consisted of three steps: 1) identification of the involved subprocesses; 2) identification and ranking of the potential failure modes, together with their causes and effects, using the risk probability number (RPN) scoring system, based on the product of three parameters (severity, frequency of occurrence and detectability, each ranging from 1 to 10); 3) identification of additional safety measures to be proposed for process quality and safety improvement. RPN upper threshold for little concern of risk was set at 125. Results: Twenty-four subprocesses were identified. Ten potential failure modes were found and scored, in terms of RPN, in the range of 42–216. The most critical failure modes consisted of internal shield misalignment, wrong Monitor Unit calculation and incorrect data entry at treatment console. Potential causes of failure included shield displacement, human errors, such as underestimation of CTV extension, mainly because of lack of adequate training and time pressures, failure in the communication between operators, and machine malfunctioning. The main effects of failure were represented by CTV underdose, wrong dose distribution and/or delivery, unintended normal tissue irradiation. As additional safety measures, the utilization of a dedicated staff for IORT, double-checking of MU calculation and data entry and finally implementation of in vivo dosimetry were suggested. Conclusions: FMEA appeared as a useful tool for prospective evaluation of patient safety in radiotherapy

  7. A comparison of robotic arm versus gantry linear accelerator stereotactic body radiation therapy for prostate cancer

    Zaorsky,Nicholas; Avkshtol,Vladimir; Dong, Yanqun; Hayes, Shelly; Hallman,Mark; Price, Robert; Sobczak, Mark; Horwitz, Eric

    2016-01-01

    Vladimir Avkshtol, Yanqun Dong, Shelly B Hayes, Mark A Hallman, Robert A Price, Mark L Sobczak, Eric M Horwitz,* Nicholas G Zaorsky* Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA *These authors contributed equally to this work Abstract: Prostate cancer is the most prevalent cancer diagnosed in men in the United States besides skin cancer. Stereotactic body radiation therapy (SBRT; 6–15 ...

  8. Accelerated partial breast irradiation using 3D conformal radiation therapy (3D-CRT)

    Purpose: We present a novel three-dimensional conformal radiation therapy (3D-CRT) technique to treat the lumpectomy cavity, plus a 1.5-cm margin, in patients with early-stage breast cancer and study its clinical feasibility. Methods and Materials: A 3D-CRT technique for partial-breast irradiation was developed using archived CT scans from 7 patients who underwent an active breathing control study. The clinical feasibility of this technique was then assessed in 9 patients who were prospectively enrolled on an Investigational Review Board-approved protocol of partial-breast irradiation. The prescribed dose was 34 Gy in 5 patients and 38.5 Gy in 4 patients, delivered in 10 fractions twice daily over 5 consecutive days. The impact of both breathing motion and patient setup uncertainty on clinical target volume (CTV) coverage was studied, and an appropriate CTV-to-PTV (planning target volume) margin was calculated. Results: By adding a CTV-to-PTV 'breathing-only' margin of 5 mm, 98%-100% of the CTV remained covered by the 95% isodose surface at the extremes of normal inhalation and normal exhalation. The 'total' CTV-to-PTV margin employed to accommodate organ motion and setup error (10 mm) was found to be sufficient to accommodate the observed uncertainty in the delivery precision. Patient tolerance was excellent, and acute toxicity was minimal. No skin changes were noted during treatment, and at the initial 4-8-week follow-up visit, only mild localized hyperpigmentation and/or erythema was observed. No instances of symptomatic radiation pneumonitis have occurred. Conclusions: Accelerated partial-breast irradiation using 3D-CRT is technically feasible, and acute toxicity to date has been minimal. A CTV-to-PTV margin of 10 mm seems to provide coverage for most 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

  9. Laser acceleration of protons from near critical density targets for application to radiation therapy

    Bulanov, S S; Pirozhkov, A S; Thomas, A G R; Willingale, L; Krushelnick, K; Maksimchuk, A

    2010-01-01

    Laser accelerated protons can be a complimentary source for treatment of oncological diseases to the existing hadron therapy facilities. We demonstrate how the protons, accelerated from near-critical density plasmas by laser pulses having relatively small power, reach energies which may be of interest for medical applications. When an intense laser pulse interacts with near-critical density plasma it makes a channel both in the electron and then in the ion density. The propagation of a laser pulse through such a self-generated channel is connected with the acceleration of electrons in the wake of a laser pulse and generation of strong moving electric and magnetic fields in the propagation channel. Upon exiting the plasma the magnetic field generates a quasi-static electric field that accelerates and collimates ions from a thin filament formed in the propagation channel. Two-dimensional Particle-in-Cell simulations show that a 100 TW laser pulse tightly focused on a near-critical density target is able to acce...

  10. Individualized Positron Emission Tomography–Based Isotoxic Accelerated Radiation Therapy Is Cost-Effective Compared With Conventional Radiation Therapy: A Model-Based Evaluation

    Bongers, Mathilda L., E-mail: ml.bongers@vumc.nl [Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam (Netherlands); Coupé, Veerle M.H. [Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam (Netherlands); De Ruysscher, Dirk [Radiation Oncology University Hospitals Leuven/KU Leuven, Leuven (Belgium); Department of Radiation Oncology, GROW Research Institute, Maastricht University Medical Center, Maastricht (Netherlands); Oberije, Cary; Lambin, Philippe [Department of Radiation Oncology, GROW Research Institute, Maastricht University Medical Center, Maastricht (Netherlands); Uyl-de Groot, Cornelia A. [Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam (Netherlands); Institute for Medical Technology Assessment, Erasmus University Rotterdam, Rotterdam (Netherlands)

    2015-03-15

    Purpose: To evaluate long-term health effects, costs, and cost-effectiveness of positron emission tomography (PET)-based isotoxic accelerated radiation therapy treatment (PET-ART) compared with conventional fixed-dose CT-based radiation therapy treatment (CRT) in non-small cell lung cancer (NSCLC). Methods and Materials: Our analysis uses a validated decision model, based on data of 200 NSCLC patients with inoperable stage I-IIIB. Clinical outcomes, resource use, costs, and utilities were obtained from the Maastro Clinic and the literature. Primary model outcomes were the difference in life-years (LYs), quality-adjusted life-years (QALYs), costs, and the incremental cost-effectiveness and cost/utility ratio (ICER and ICUR) of PET-ART versus CRT. Model outcomes were obtained from averaging the predictions for 50,000 simulated patients. A probabilistic sensitivity analysis and scenario analyses were carried out. Results: The average incremental costs per patient of PET-ART were €569 (95% confidence interval [CI] €−5327-€6936) for 0.42 incremental LYs (95% CI 0.19-0.61) and 0.33 QALYs gained (95% CI 0.13-0.49). The base-case scenario resulted in an ICER of €1360 per LY gained and an ICUR of €1744 per QALY gained. The probabilistic analysis gave a 36% probability that PET-ART improves health outcomes at reduced costs and a 64% probability that PET-ART is more effective at slightly higher costs. Conclusion: On the basis of the available data, individualized PET-ART for NSCLC seems to be cost-effective compared with CRT.

  11. Individualized Positron Emission Tomography–Based Isotoxic Accelerated Radiation Therapy Is Cost-Effective Compared With Conventional Radiation Therapy: A Model-Based Evaluation

    Purpose: To evaluate long-term health effects, costs, and cost-effectiveness of positron emission tomography (PET)-based isotoxic accelerated radiation therapy treatment (PET-ART) compared with conventional fixed-dose CT-based radiation therapy treatment (CRT) in non-small cell lung cancer (NSCLC). Methods and Materials: Our analysis uses a validated decision model, based on data of 200 NSCLC patients with inoperable stage I-IIIB. Clinical outcomes, resource use, costs, and utilities were obtained from the Maastro Clinic and the literature. Primary model outcomes were the difference in life-years (LYs), quality-adjusted life-years (QALYs), costs, and the incremental cost-effectiveness and cost/utility ratio (ICER and ICUR) of PET-ART versus CRT. Model outcomes were obtained from averaging the predictions for 50,000 simulated patients. A probabilistic sensitivity analysis and scenario analyses were carried out. Results: The average incremental costs per patient of PET-ART were €569 (95% confidence interval [CI] €−5327-€6936) for 0.42 incremental LYs (95% CI 0.19-0.61) and 0.33 QALYs gained (95% CI 0.13-0.49). The base-case scenario resulted in an ICER of €1360 per LY gained and an ICUR of €1744 per QALY gained. The probabilistic analysis gave a 36% probability that PET-ART improves health outcomes at reduced costs and a 64% probability that PET-ART is more effective at slightly higher costs. Conclusion: On the basis of the available data, individualized PET-ART for NSCLC seems to be cost-effective compared with CRT

  12. Cardiac risks in patients with lung cancer in dynamics of carrying out radiation therapy on linear accelerator

    During radiation therapy (RT) patients on linear accelerator progress of chronic cardiac insufficiency has been pointed out. The patients with associated cardiac diseases in form of IHD, in case of combination of essential hypertension and IHD have shown increase of frequency of complications development of the part of cardiovascular system on RT in 70% og cases. Rhythm disorder and asequence, clear ECG-signs of ischemia in form of repolarization processes, decrease of voltage or T waive inversion, diastole dysfunction on insufficient relaxation type and systolic myocardium dysfunction of left ventricle are to be treated as substantial markers of cardiovascular pathology on RT

  13. 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.)

  14. Radiation therapy physics

    1995-01-01

    The aim of this book is to provide a uniquely comprehensive source of information on the entire field of radiation therapy physics. The very significant advances in imaging, computational, and accelerator technologies receive full consideration, as do such topics as the dosimetry of radiolabeled antibodies and dose calculation models. The scope of the book and the expertise of the authors make it essential reading for interested physicians and physicists and for radiation dosimetrists.

  15. A Phase I Study of Short-Course Accelerated Whole Brain Radiation Therapy for Multiple Brain Metastases

    Caravatta, Luciana; Deodato, Francesco; Ferro, Marica [Department of Radiation Oncology, Fondazione di Ricerca e Cura ' Giovanni Paolo II' , Universita Cattolica del S. Cuore, Campobasso (Italy); Macchia, Gabriella, E-mail: gmacchia@rm.unicatt.it [Department of Radiation Oncology, Fondazione di Ricerca e Cura ' Giovanni Paolo II' , Universita Cattolica del S. Cuore, Campobasso (Italy); Massaccesi, Mariangela [Department of Radiation Oncology, Fondazione di Ricerca e Cura ' Giovanni Paolo II' , Universita Cattolica del S. Cuore, Campobasso (Italy); Cilla, Savino [Medical Physics Unit, Fondazione di Ricerca e Cura ' Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Padula, Gilbert D.A. [Department of Radiation Oncology, The Lacks Cancer Center Saint Mary' s Health Care, Grand Rapids, Michigan (United States); Mignogna, Samantha; Tambaro, Rosa [Department of Palliative Therapies, Fondazione di Ricerca e Cura ' Giovanni Paolo II' , Universita Cattolica del S. Cuore, Campobasso (Italy); Carrozza, Francesco [Department of Oncology, A. Cardarelli Hospital, Campobasso (Italy); Flocco, Mariano [Madre Teresa di Calcutta Hospice, Larino (Italy); Cantore, Giampaolo [Department of Neurological Sciences, Istituto Neurologico Mediterraneo Neuromed, Istituto di Ricovero e Cura a Carattere Scientifico, Pozzilli (Italy); Scapati, Andrea [Department of Radiation Oncology, ' San Francesco' Hospital, Nuoro (Italy); Buwenge, Milly [Department of Radiotherapy, Mulago Hospital, Kampala (Uganda); and others

    2012-11-15

    Purpose: To define the maximum tolerated dose (MTD) of a SHort-course Accelerated whole brain RadiatiON therapy (SHARON) in the treatment of patients with multiple brain metastases. Methods and Materials: A phase 1 trial in 4 dose-escalation steps was designed: 12 Gy (3 Gy per fraction), 14 Gy (3.5 Gy per fraction), 16 Gy (4 Gy per fraction), and 18 Gy (4.5 Gy per fraction). Eligibility criteria included patients with unfavorable recursive partitioning analysis (RPA) class > or =2 with at least 3 brain metastases or metastatic disease in more than 3 organ systems, and Eastern Cooperative Oncology Group (ECOG) performance status {<=}3. Treatment was delivered in 2 days with twice-daily fractionation. Patients were treated in cohorts of 6-12 to define the MTD. The dose-limiting toxicity (DLT) was defined as any acute toxicity {>=}grade 3, according to the Radiation Therapy Oncology Group scale. Information on the status of the main neurologic symptoms and quality of life were recorded. Results: Characteristics of the 49 enrolled patients were as follows: male/female, 30/19; median age, 66 years (range, 23-83 years). ECOG performance status was <3 in 46 patients (94%). Fourteen patients (29%) were considered to be in recursive partitioning analysis (RPA) class 3. Grade 1-2 acute neurologic (26.4%) and skin (18.3%) toxicities were recorded. Only 1 patient experienced DLT (neurologic grade 3 acute toxicity). With a median follow-up time of 5 months (range, 1-23 months), no late toxicities have been observed. Three weeks after treatment, 16 of 21 symptomatic patients showed an improvement or resolution of presenting symptoms (overall symptom response rate, 76.2%; confidence interval 0.95: 60.3-95.9%). Conclusions: Short-course accelerated radiation therapy in twice-daily fractions for 2 consecutive days is tolerated up to a total dose of 18 Gy. A phase 2 study has been planned to evaluate the efficacy on overall survival, symptom control, and quality of life indices.

  16. Early-Stage Breast Cancer Treated With 3-Week Accelerated Whole-Breast Radiation Therapy and Concomitant Boost

    Chadha, Manjeet, E-mail: MChadha@chpnet.org [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States); Woode, Rudolph; Sillanpaa, Jussi [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States); Lucido, David [Department of Biostatistics, Beth Israel Medical Center, New York, New York (United States); Boolbol, Susan K.; Kirstein, Laurie; Osborne, Michael P.; Feldman, Sheldon [Division of Breast Surgery, Beth Israel Medical Center, New York, New York (United States); Harrison, Louis B. [Department of Radiation Oncology, Beth Israel Medical Center, New York, New York (United States)

    2013-05-01

    Purpose: To report early outcomes of accelerated whole-breast radiation therapy with concomitant boost. Methods and Materials: This is a prospective, institutional review board-approved study. Eligibility included stage TisN0, T1N0, and T2N0 breast cancer. Patients receiving adjuvant chemotherapy were ineligible. The whole breast received 40.5 Gy in 2.7-Gy fractions with a concomitant lumpectomy boost of 4.5 Gy in 0.3-Gy fractions. Total dose to the lumpectomy site was 45 Gy in 15 fractions over 19 days. Results: Between October 2004 and December 2010, 160 patients were treated; stage distribution was as follows: TisN0, n=63; T1N0, n=88; and T2N0, n=9. With a median follow-up of 3.5 years (range, 1.5-7.8 years) the 5-year overall survival and disease-free survival rates were 90% (95% confidence interval [CI] 0.84-0.94) and 97% (95% CI 0.93-0.99), respectively. Five-year local relapse-free survival was 99% (95% CI 0.96-0.99). Acute National Cancer Institute/Common Toxicity Criteria grade 1 and 2 skin toxicity was observed in 70% and 5%, respectively. Among the patients with ≥2-year follow-up no toxicity higher than grade 2 on the Late Effects in Normal Tissues–Subjective, Objective, Management, and Analytic scale was observed. Review of the radiation therapy dose–volume histogram noted that ≥95% of the prescribed dose encompassed the lumpectomy target volume in >95% of plans. The median dose received by the heart D{sub 05} was 215 cGy, and median lung V{sub 20} was 7.6%. Conclusions: The prescribed accelerated schedule of whole-breast radiation therapy with concomitant boost can be administered, achieving acceptable dose distribution. With follow-up to date, the results are encouraging and suggest minimal side effects and excellent local control.

  17. Radiation Therapy

    ... goal of causing less harm to the surrounding healthy tissue. You don't have to worry that you'll glow in the dark after radiation treatment: People who receive external radiation are not radioactive. You' ...

  18. Intraoperative radiation therapy using a mobile electron linear accelerator: field matching for large-field electron irradiation

    Intraoperative radiation therapy (IORT) consists of delivering a large, single-fraction dose of radiation to a surgically exposed tumour or tumour bed at the time of surgery. With the availability of a mobile linear accelerator in the OR, IORT procedures have become more feasible for medical centres and more accessible to cancer patients. Often the area requiring irradiation is larger than what the treatment applicators will allow, and therefore, two or more adjoining fields are used. Unfortunately, the divergence and scattering of the electron beams may cause significant dose variations in the region of the field junction. Furthermore, because IORT treatments are delivered in a large single fraction, the effects of underdosing or overdosing could be more critical when compared to fractionated external beam therapy. Proper matching of the fields is therefore an important technical aspect of treatment delivery. We have studied the matching region using the largest flat applicator available for three different possibilities: abutting the fields, leaving a small gap or creating an overlap. Measurements were done using film dosimetry for the available energies of 4, 6, 9 and 12 MeV. Our results show the presence of clinically significant cold spots for the low-energy beams when the fields are either gapped or abutted, suggesting that the fields should be overlapped. No fields should be gapped. The results suggest that an optimal dose distribution may be obtained by overlapping the fields at 4 and 6 MeV and simply abutting the fields at 9 and 12 MeV. However, due to uncertainties in the placement of lead shields during treatment delivery, one may wish to consider overlapping the higher energy fields as well. (note)

  19. 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

  20. SU-E-T-03: 3D GPU-Accelerated Secondary Checks of Radiation Therapy Treatment Plans

    Purpose: Redundant treatment verifications in conformal and intensity-modulated radiation therapy techniques are traditionally performed with single point calculations. New solutions can replace these checks with 3D treatment plan verifications. This work describes a software tool (Mobius3D, Mobius Medical Systems) that uses a GPU-accelerated collapsed cone algorithm to perform 3D independent verifications of TPS calculations. Methods: Mobius3D comes with reference beam models for common linear accelerators. The system uses an independently developed collapsed cone algorithm updated with recent enhancements. 144 isotropically-spaced cones are used for each voxel for calculations. These complex calculations can be sped up by using GPUs. Mobius3D calculate dose using DICOM information coming from TPS (CT, RT Struct, RT Plan RT Dose). DVH-metrics and 3D gamma tests can be used to compare both TPS and secondary calculations. 170 patients treated with all common techniques as 3DCFRT (including wedged), static and dynamic IMRT and VMAT have been successfully verified with this solution. Results: Calculation times are between 3–5 minutes for 3DCFRT treatments and 15–20 for most complex dMLC and VMAT plans. For all PTVs mean dose and 90% coverage differences are (1.12±0.97)% and (0.68±1.19)%, respectively. Mean dose discrepancies for all OARs is (0.64±1.00)%. 3D gamma (global, 3%/3 mm) analysis shows a mean passing rate of (97.8 ± 3.0)% for PTVs and (99.0±3.0)% for OARs. 3D gamma pasing rate for all voxels in CT has a mean value of (98.5±1.6)%. Conclusion: Mobius3D is a powerful tool to verify all modalities of radiation therapy treatments. Dose discrepancies calculated by this system are in good agreement with TPS. The use of reference beam data results in time savings and can be used to avoid the propagation of errors in original beam data into our QA system. GPU calculations permit enhanced collapsed cone calculations with reasonable calculation times

  1. SU-E-T-03: 3D GPU-Accelerated Secondary Checks of Radiation Therapy Treatment Plans

    Clemente, F; Perez, C [Hospital Central de la Defensa Gomez Ulla, Madrid, Madrid (Spain)

    2014-06-01

    Purpose: Redundant treatment verifications in conformal and intensity-modulated radiation therapy techniques are traditionally performed with single point calculations. New solutions can replace these checks with 3D treatment plan verifications. This work describes a software tool (Mobius3D, Mobius Medical Systems) that uses a GPU-accelerated collapsed cone algorithm to perform 3D independent verifications of TPS calculations. Methods: Mobius3D comes with reference beam models for common linear accelerators. The system uses an independently developed collapsed cone algorithm updated with recent enhancements. 144 isotropically-spaced cones are used for each voxel for calculations. These complex calculations can be sped up by using GPUs. Mobius3D calculate dose using DICOM information coming from TPS (CT, RT Struct, RT Plan RT Dose). DVH-metrics and 3D gamma tests can be used to compare both TPS and secondary calculations. 170 patients treated with all common techniques as 3DCFRT (including wedged), static and dynamic IMRT and VMAT have been successfully verified with this solution. Results: Calculation times are between 3–5 minutes for 3DCFRT treatments and 15–20 for most complex dMLC and VMAT plans. For all PTVs mean dose and 90% coverage differences are (1.12±0.97)% and (0.68±1.19)%, respectively. Mean dose discrepancies for all OARs is (0.64±1.00)%. 3D gamma (global, 3%/3 mm) analysis shows a mean passing rate of (97.8 ± 3.0)% for PTVs and (99.0±3.0)% for OARs. 3D gamma pasing rate for all voxels in CT has a mean value of (98.5±1.6)%. Conclusion: Mobius3D is a powerful tool to verify all modalities of radiation therapy treatments. Dose discrepancies calculated by this system are in good agreement with TPS. The use of reference beam data results in time savings and can be used to avoid the propagation of errors in original beam data into our QA system. GPU calculations permit enhanced collapsed cone calculations with reasonable calculation times.

  2. Special radiation protection aspects of medical accelerators

    Silari, Marco

    2001-01-01

    Radiation protection aspects relevant to medical accelerators are discussed. An overview is first given of general safety requirements. Next. shielding and labyrinth design are discussed in some detail for the various types of accelerators, devoting more attention to hadron machines as they are far less conventional than electron linear accelerators. Some specific aspects related to patient protection are also addressed. Finally, induced radioactivity in accelerator components and shielding walls is briefly discussed. Three classes of machines are considered: (1) medical electron linacs for 'conventional' radiation therapy. (2) low energy cyclotrons for production of radionuclides mainly for medical diagnostics and (3) medium energy cyclotrons and synchrotrons for advanced radiation therapy with protons or light ion beams (hadron therapy). (51 refs).

  3. Proton Therapy - Accelerating Protons to Save Lives

    Keppel, Cynthia [Hampton University Proton Therapy

    2011-10-25

    In 1946, physicist Robert Wilson first suggested that protons could be used as a form of radiation therapy in the treatment of cancer because of the sharp drop-off that occurs on the distal edge of the radiation dose. Research soon confirmed that high-energy protons were particularly suitable for treating tumors near critical structures, such as the heart and spinal column. The precision with which protons can be delivered means that more radiation can be deposited into the tumor while the surrounding healthy tissue receives substantially less or, in some cases, no radiation. Since these times, particle accelerators have continuously been used in cancer therapy and today new facilities specifically designed for proton therapy are being built in many countries. Proton therapy has been hailed as a revolutionary cancer treatment, with higher cure rates and fewer side effects than traditional X-ray photon radiation therapy. Proton therapy is the modality of choice for treating certain small tumors of the eye, head or neck. Because it exposes less of the tissue surrounding a tumor to the dosage, proton therapy lowers the risk of secondary cancers later in life - especially important for young children. To date, over 80,000 patients worldwide have been treated with protons. Currently, there are nine proton radiation therapy facilities operating in the United States, one at the Hampton University Proton Therapy Institute. An overview of the treatment technology and this new center will be presented.

  4. Shielding data for hadron-therapy ion accelerators: Attenuation of secondary radiation in concrete

    Agosteo, S; Sagia, E; Silari, M

    2014-01-01

    The secondary radiation field produced by seven different ion species (from hydrogen to nitrogen), impinging onto thick targets made of either iron or ICRU tissue, was simulated with the FLUKA Monte Carlo code, and transported through thick concrete shields: the ambient dose equivalent was estimated and shielding parameters evaluated. The energy for each ion beam was set in order to reach a maximum penetration in ICRU tissue of 290 mm (equivalent to the therapeutic range of 430 MeV/amu carbon ions). Source terms and attenuation lengths are given as a function of emission angle and ion species, along with fits to the Monte Carlo data, for shallow depth and deep penetration in the shield. Trends of source terms and attenuation lengths as a function of neutron emission angle and ion species impinging on tar- get are discussed. A comparison of double differential distributions of neutrons with results from similar simulation works reported in the literature is also included. The aim of this work is to provide shi...

  5. Short course continuous, hyperfractionated, accelerated radiation therapy (CHART) as preoperative treatment for rectal cancer

    Brooks, S.; Glynne-Jones, R.; Harrison, M.; Makris, A. [Mount Vernon Cancer Center, Northwood, Middlesex (United Kingdom); Novell, R.; Brown, K. [Luton and Dunstable Hospital (United Kingdom)

    2006-12-15

    Determine feasibility and toxicity of preoperative short course pelvic CHART (25 Gy in 15 fractions over 5 days) for treatment of clinically resectable primary rectal tumours. Between 1998 and 2004, 20 patients with clinically staged T3 resectable rectal carcinoma were treated in this prospective pilot study with preoperative short course CHART to their pelvis. The aim was for total mesorectal excision within 7 days. Radiation toxicity, surgical morbidity, locoregional control (LRC), overall (OS), cause specific (CSS) and disease free survival (DFS) outcomes were documented. Nineteen of the 20 patients completed planned radiotherapy. One discontinued radiotherapy due to toxicity. All patients underwent potentially curative radical surgery. One patient developed grade 3, and three patients grade 2 gastrointestinal toxicity. With a median follow-up of 31 months (range 0.9-88), there is no grade 3, 4 or 5 late toxicity. Two patients experienced grade 2, and three patients grade 1 late bowel toxicity. Two patients died from postoperative complications, and two developed grade 2 abdominal wound infections. At 3 years LRC is 95% (95% CI 83-100), OS 72% (95% CI 51-94), CSS 86% (95% CI 68-100) and DFS 80% (95% CI 60-100). Two patients died from metastatic disease, one patient from a second primary and one patient is alive after successful resection of hepatic metastases. This small study suggests preoperative short course CHART for clinically resectable rectal carcinoma is feasible with acceptable compliance and tolerable side effects.

  6. Radioprotectors and Radiomitigators for Improving Radiation Therapy: The Small Business Innovation Research (SBIR) Gateway for Accelerating Clinical Translation.

    Prasanna, Pataje G S; Narayanan, Deepa; Hallett, Kory; Bernhard, Eric J; Ahmed, Mansoor M; Evans, Gregory; Vikram, Bhadrasain; Weingarten, Michael; Coleman, C Norman

    2015-09-01

    Although radiation therapy is an important cancer treatment modality, patients may experience adverse effects. The use of a radiation-effect modulator may help improve the outcome and health-related quality of life (HRQOL) of patients undergoing radiation therapy either by enhancing tumor cell killing or by protecting normal tissues. Historically, the successful translation of radiation-effect modulators to the clinic has been hindered due to the lack of focused collaboration between academia, pharmaceutical companies and the clinic, along with limited availability of support for such ventures. The U.S. Government has been developing medical countermeasures against accidental and intentional radiation exposures to mitigate the risk and/or severity of acute radiation syndrome (ARS) and the delayed effects of acute radiation exposures (DEARE), and there is now a drug development pipeline established. Some of these medical countermeasures could potentially be repurposed for improving the outcome of radiation therapy and HRQOL of cancer patients. With the objective of developing radiation-effect modulators to improve radiotherapy, the Small Business Innovation Research (SBIR) Development Center at the National Cancer Institute (NCI), supported by the Radiation Research Program (RRP), provided funding to companies from 2011 to 2014 through the SBIR contracts mechanism. Although radiation-effect modulators collectively refer to radioprotectors, radiomitigators and radiosensitizers, the focus of this article is on radioprotection and mitigation of radiation injury. This specific SBIR contract opportunity strengthened existing partnerships and facilitated new collaborations between academia and industry. In this commentary, we assess the impact of this funding opportunity, outline the review process, highlight the organ/site-specific disease needs in the clinic for the development of radiation-effect modulators, provide a general understanding of a framework for gathering

  7. Long-term Outcomes in Treatment of Invasive Bladder Cancer With Concomitant Boost and Accelerated Hyperfractionated Radiation Therapy

    Canyilmaz, Emine, E-mail: dremocan@yahoo.com [Department of Radiation Oncology, Karadeniz Technical University, Trabzon (Turkey); Yavuz, Melek Nur [Department of Radiation Oncology, Akdeniz University, Antalya (Turkey); Serdar, Lasif [Department of Radiation Oncology, Karadeniz Technical University, Trabzon (Turkey); Uslu, Gonca Hanedan; Zengin, Ahmet Yasar [Department of Radiation Oncology, Kanuni Research and Education Hospital, Trabzon (Turkey); Aynaci, Ozlem; Haciislamoglu, Emel; Bahat, Zumrut; Yoney, Adnan [Department of Radiation Oncology, Karadeniz Technical University, Trabzon (Turkey)

    2014-11-01

    Purpose: The aim of this study was to evaluate the long-term clinical efficacy and toxicity of concomitant boost and accelerated hyperfractionated radiation therapy (CBAHRT) in patients with invasive bladder cancer. Methods and Materials: Between October 1997 and September 2012, 334 patients with diagnoses of invasive bladder cancer were selected. These patients received CBAHRT as a bladder-conserving approach. The treatment consisted of a dose of 45 Gy/1.8 Gy to the whole pelvis with a daily concomitant boost of 1.5 Gy to the tumor. Total dose was 67.5 Gy in 5 weeks. A total of 32 patients (10.3%) had a diagnosis of stage T1, 202 (64.3%) were at stage T2, 46 (14.6%) were at stage T3a, 22 (7%) were at stage T3b, and 12 (3.8%) were at stage T4a. Results: The follow-up period was 33.1 months (range, 4.3-223.3 months). Grade 3 late intestinal toxicity was observed in 9 patients (2.9%), whereas grade 3 late urinary toxicity was observed in 8 patients (2.5%). The median overall survival (OS) was 26.3 months (95% confidence interval [CI]: 21.4-31.2). The 5-, 10, and 15-year OS rates were 32.1% (standard error [SE], ± 0.027), 17.9% (SE, ± 0.025) and 12.5% (SE, ± 0.028), respectively. The median cause-specific survival (CSS) was 42.1 months (95% CI: 28.7-55.5). The 5-, 10-, and 15-year CSS rates were 43.2% (SE, ± 0.03), 30.3% (SE, ± 0.03), and 28% (SE, ± 0.04), respectively. The median relapse-free survival (RFS) was 111.8 months (95% CI: 99.6-124). The 5-, 10-, and 15-year RFS rates were 61.9% (SE, ± 0.03), 57.6% (SE, ± 0.04), and 48.2% (SE, ± 0.07), respectively. Conclusions: The CBAHRT technique demonstrated acceptable toxicity and local control rates in patients with invasive bladder cancer, and this therapy facilitated bladder conservation. In selected patients, the CBAHRT technique is a practical alternative treatment option with acceptable 5-, 10-, and 15-year results in patients undergoing cystectomy as well as concurrent chemoradiation therapy.

  8. External Radiation Therapy

    Full Text Available ... older the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms ... prostate. [beeping] Narrator: The more common form of radiation therapy is external beam. A typical treatment takes seven ...

  9. Validating Fiducial Markers for Image-Guided Radiation Therapy for Accelerated Partial Breast Irradiation in Early-Stage Breast Cancer

    Purpose: Image-guided radiation therapy (IGRT) may be beneficial for accelerated partial breast irradiation (APBI). The goal was to validate the use of intraparenchymal textured gold fiducials in patients receiving APBI. Methods and Materials: Twenty-six patients were enrolled on this prospective study that had three or four textured gold intraparenchymal fiducials placed at the periphery of the lumpectomy cavity and were treated with three-dimensional (3D) conformal APBI. Free-breathing four-dimensional computed tomography image sets were obtained pre- and posttreatment, as were daily online megavoltage (MV) orthogonal images. Intrafraction motion, variations in respiratory motion, and fiducial marker migration were calculated using the 3D coordinates of individual fiducials and a calculated center of mass (COM) of the fiducials. We also compared the relative position of the fiducial COM with the geometric center of the seroma. Results: There was less than 1 mm of intrafraction respiratory motion, variation in respiratory motion, or fiducial marker migration. The change in seroma position relative to the fiducial COM was 1 mm ± 1 mm. The average position of the geometric seroma relative to the fiducial COM pretreatment compared with posttreatment was 1 mm ± 1 mm. The largest daily variation in displacement when using bony landmark was in the anteroposterior direction and two standard deviations (SD) of this variation was 10 mm. The average variation in daily separation between the fiducial pairs from daily MV images was 3 mm ± 3 mm therefore 2 SD is 6 mm. Conclusion: Fiducial markers are stable throughout the course of APBI. Planning target volume margins when using bony landmarks should be 10 mm and can be reduced to 6 mm if using fiducials.

  10. Workshop on the accelerator for particle therapy

    A two-day workshop on the accelerator for particle therapy was held on August 22-23, 1990, with the aim of mutual understanding of medical accelerators among investigators. The state-of-the-art facilities in Japan and medical proton accelerators in Japan and other countries were introduced. This is a compilation of papers presented at the workshop: (1) particle radiotherapy at the National Institute of Radiological Sciences (NIRS); (2) proton therapy; (3) treatment planning, especially for photon and electron therapies; (4) heavy ion synchrotron project at the NIRS; (5) medical proton accelerator project of Tsukuba University and recent status of Loma Linda University Medical Center Proton Beam Facility; (6) inspection report on the Loma Linda University Medical Center Proton Beam Facility; (7) accelerator project of Kyoto University; (8) actual conditions of the 7 MeV proton linear accelerator; (9) design study of superconducting compact cyclotron prototype model; (10) medical superconducting prototype cyclotron; (11) RCNP cyclotron cascade project; (12) beam extraction from synchrotron; (13) radiation safety design in high energy particle accelerator facilities. (N.K.)

  11. Phase I and pharmacokinetic study of preirradiation chemotherapy with BCNU, cisplatin, etoposide, and accelerated radiation therapy in patients with high-grade glioma

    Purpose: We conducted a Phase I study of bischloroethylnitrosourea (BCNU), cisplatin, and oral etoposide administered prior to and during accelerated hyperfractionated radiation therapy in newly diagnosed high-grade glioma. Pharmacokinetic studies of oral etoposide were also done. Methods and Materials: Patients started chemotherapy after surgery but prior to definitive radiation therapy (160 cGy twice daily x 15 days; 4800 cGy total). Initial chemotherapy consisted of BCNU 40 mg/m2 days 1-3, cisplatin 30 mg/m2 days 1-3 and 29-31, and etoposide 50 mg orally days 1-14 and 29-42, repeated in 8 weeks concurrent with radiation therapy. BCNU 200 mg/m2 every 8 weeks x 4 cycles was given after radiation therapy. Results: Sixteen patients, 5 with grade 3 anaplastic astrocytoma and 11 with glioblastoma were studied. Grade 3-4 leukopenia (38%) and thrombocytopenia (31%) were dose-limiting. Other toxicities were anorexia (81%), nausea (94%), emesis (56%), alopecia (88%), and ototoxicity (38%). The maximum tolerated dose was BCNU 40 mg/m2 days 1-3, cisplatin 20 mg/m2 days 1-3 and 29-31, and oral etoposide 50 mg days 1-21 and 29-49 prior to radiation therapy and repeated in 8 weeks with the start of radiation therapy followed by BCNU 200 mg/m2 every 8 weeks for 4 cycles. Median time to progression and survival were 13 and 14 months respectively. Responses occurred in 2 of 9 (22%) patients with evaluable disease. In pharmacokinetic studies, all patients achieved plasma concentrations of >0.1 μg/ml etoposide (the in vitro radiosensitizing threshold), following a 50 mg oral dose. The mean ± SD 2 hr and 6 hr plasma concentrations were 0.92 ± 0.43 μg/ml and 0.36 ± 0.12 μg/ml, respectively. Estimated duration of exposure to >0.1 μg/ml etoposide was 10-17 hr. Conclusions: Preirradiation chemotherapy with BCNU, cisplatin, and oral etoposide with accelerated hyperfractionated radiation therapy in high-grade gliomas is feasible and merits further investigation. Sustained

  12. Imaging in radiation therapy

    Radiation therapy is an important part of cancer treatment in which cancer patients are treated using high-energy radiation such as x-rays, gamma rays, electrons, protons, and neutrons. Currently, about half of all cancer patients receive radiation treatment during their whole cancer care process. The goal of radiation therapy is to deliver the necessary radiation dose to cancer cells while minimizing dose to surrounding normal tissues. Success of radiation therapy highly relies on how accurately 1) identifies the target and 2) aim radiation beam to the target. Both tasks are strongly dependent of imaging technology and many imaging modalities have been applied for radiation therapy such as CT (Computed Tomography), MRI (Magnetic Resonant Image), and PET (Positron Emission Tomography). Recently, many researchers have given significant amount of effort to develop and improve imaging techniques for radiation therapy to enhance the overall quality of patient care. For example, advances in medical imaging technology have initiated the development of the state of the art radiation therapy techniques such as Intensity Modulated Radiation Therapy (IMRT), gated radiation therapy, tomotherapy, and Image Guided Radiation Therapy (IGRT). Capability of determining the local tumor volume and location of the tumor has been significantly improved by applying single or multi-modality imaging for static or dynamic target. The use of multi-modality imaging provides a more reliable tumor volume, eventually leading to a better definitive local control. Image registration technique is essential to fuse two different image modalities and has been in significant improvement. Imaging equipment and their common applications that are in active use and/or under development in radiation therapy are reviewed

  13. External Radiation Therapy

    Full Text Available ... the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms of radiation for prostate cancer. They really boil down to two different types. ...

  14. External Radiation Therapy

    Full Text Available ... frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms of radiation for prostate ... typical treatment takes seven weeks. Gunnar Zagars, M.D.: A patient comes in every day, Monday to ...

  15. A phase II trial of accelerated hypofractionated three-dimensional conformal radiation therapy in locally advanced non-small cell lung cancer

    Purpose: The aim of this study is to evaluate the safety and efficacy of accelerated hypofractionated radiotherapy (HypoRT) combined with sequential chemotherapy in locally advanced non-small cell lung cancer (NSCLC). Materials and methods: A total of 34 patients with stage III NSCLC were enrolled. All patients received accelerated HypoRT (initially 50 Gy/20 fractions, then a fraction dose of 3 Gy) using three-dimensional conformal radiation therapy (3D-CRT), omitting elective nodal irradiation (ENI), to a total dose of 65-68 Gy. All patients received two cycles of induction chemotherapy; 1-2 cycles of consolidation chemotherapy were given to 31 patients. The primary outcome measure was a profile of radiation toxicity. The secondary endpoints included overall survival (OS), progression-free survival (PFS), locoregional PFS (LR-PFS) and the pattern of initial failure. Results: Radiation toxicity was minimal. The median and 3-year OS, PFS were 19.0 months, 32.1%; 10.0 months, 29.8%, respectively. The 1-, 2-, and 3-year LR-PFS were 69.6%, 60.9% and 60.9%, respectively. No patient experienced isolated elective nodal failure as the first site of failure. Conclusion: This study suggests that accelerated HypoRT using 3D-CRT omitting ENI can be used in combination with sequential chemotherapy in locally advanced NSCLC.

  16. 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

  17. Radiation therapy dosimetry system

    New therapeutic treatments generally aim to increase therapeutic efficacy while minimizing toxicity. Many aspects of radiation dosimetry have been studied and developed particularly in the field of external radiation. The success of radiotherapy relies on monitoring the dose of radiation to which the tumor and the adjacent tissues are exposed. Radiotherapy techniques have evolved through a rapid transition from conventional three-dimensional (3D) conformal radiation therapy to intensity-modulated radiation therapy (IMRT) treatments or radiosurgery and robotic radiation therapy. These advances push the frontiers in our effort to provide better patient care by improving the precision of the absorbed dose delivered. This paper presents state-of-the art radiation therapy dosimetry techniques as well as the value of integral dosimetry (INDOS), which shows promise in the fulfillment of radiation therapy dosimetry requirements. - highlights: • Pre-treatment delivery and phantom dosimetry in brachytherapy treatments were analyzed. • Dose distribution in the head and neck was estimated by physical and mathematical dosimetry. • Electron beam flattening was acquired by means of mathematical, physical and “in vivo” dosimetry. • Integral dosimetry (INDOS) has been suggested as a routine dosimetric method in all radiation therapy treatments

  18. Determination Of Some Specific Parameters In Energy Spectrum Of Electron Beams From The Radiation Therapy Linear Accelerator Siemens PRIMUS

    Mean energy E0 and maximum probability energy Ep,0 of electron beams on the patient skin are important parameters using in radiotherapy. This report presents the experimental method assessing quality of 12 MeV electron beam from Radiation therapy Linac-SIEMENS Primus at the National Cancer Hospital (K Hospital). Absorbed dose distribution and absorbed curve of a certain field size at the depths in medium have been defined by absorbed measurement technique in water phantom. The determination of Ep,0 and E0 is based on the use of semi- empirical relationships between electron energy and range parameters, which are determined in percentage depth dose curve for electron beam in water phantom. (author)

  19. Radiation therapy physics

    Hendee, William R; Hendee, Eric G

    2013-01-01

    The Third Edition of Radiation Therapy Physics addresses in concise fashion the fundamental diagnostic radiologic physics principles as well as their clinical implications. Along with coverage of the concepts and applications for the radiation treatment of cancer patients, the authors have included reviews of the most up-to-date instrumentation and critical historical links. The text includes coverage of imaging in therapy planning and surveillance, calibration protocols, and precision radiation therapy, as well as discussion of relevant regulation and compliance activities. It contains an upd

  20. Radiation Therapy (For Parents)

    ... be some permanent changes to the color and elasticity of the skin. How can you help? Dress ... to Home and School Cancer Center Cancer Basics Types of Cancer Teens Get Radiation Therapy Chemotherapy Dealing ...

  1. External Radiation Therapy

    Full Text Available ... prostate or when the patient is older the treatment that is frequently used is radiation therapy. Gunnar ... different types. There's what we call external beam treatment, which is given from an x-ray machine, ...

  2. External Radiation Therapy

    Full Text Available ... given from an x-ray machine, and there's a variety called interstitial implantation, which uses radioactive seeds. ... common form of radiation therapy is external beam. A typical treatment takes seven weeks. Gunnar Zagars, M. ...

  3. Radiation control in accelerator facilities

    In view of radiation control, particle accelerator facilities have posed various problems involving radiation (mainly neutron) leakage, occupational exposure, environmental aspects in the surrounding area, and waste management. The intent of the workshop was to discuss these problems. This report contains nine topics that were presented and discussed: (1) Radiation safety system for the AVF cyclotron and the cyclotron cascade project at the Research Center for Nuclear Physics, Osaka University; (2) Calculation for the shielding design in the RIKEN Ring Cyclotron Facility; (3) Shielding design method for high-energy protons in the National Laboratory for High-energy Physics (KEK); (4) Radiation safety programme for the uses of medical accelerators in the National Institute of Radiological Sciences; (5) Development of the new stack air monitor; (6) Environmental radiation monitoring in the vicinity of the intense 14 Mev neutron source facility; (7) Radiation control around the KEK-proton synchroton; (8) Radiation safety control system for the RIKEN Ring Cyclotron; (9) Evaluation of radioactivity and skyshine induced by neutron production in an accelerator facility. (Namekawa, K.)

  4. Development of the accelerator-based technique for hadron therapy

    Hadron therapy with protons and carbon ions is one of the most effective branches in radiation oncology. It has advantages over therapy using gamma-radiation and electron beams. Fifty thousands of patients per year need such a treatment in Russia. Review of the main modern trends in the development of accelerators for therapy and treatment techniques concerned with respiratory gated irradiation and scanning with the intensity modulated pencil beams is given. Main stages of forming, time-structure and main parameters of the beams used in proton therapy as well as requirements to medicine accelerators are considered. Main results of testing with the beam of C235-V3 cyclotron for the first Russian specialized hospital proton therapy center in Dimitrovgrad are presented. Using of the superconducting accelerators and gantry systems for hadron therapy is considered

  5. Dose non-linearity of the dosimetry system and possible monitor unit errors on medical linear accelerators used in conventional and intensity-modulated radiation therapy

    Muhammad Wazir

    2012-01-01

    Full Text Available The purpose of this work is to study dose non-linearity in medical linear accelerators used in conventional radiotherapy and intensity-modulated radiation therapy. Open fields, as well as the enhanced dynamic wedge ones, were used to collect data for 6 MV and 15 MV photon beams obtained from the VARIAN linear accelerator. Beam stability was checked and confirmed for different dose rates, energies, and application of enhanced dynamic wedge by calculating the charge per monitor unit. Monitor unit error was calculated by the two-exposure method for open and enhanced dynamic wedge beams of 6 MV and 15 MV photons. A significant monitor unit error with maximum values of ±2.05931 monitor unit and ±2.44787 monitor unit for open and enhanced dynamic wedge beams, respectively, both energy and dose rate dependent, was observed both in the open photon beam and enhanced dynamic wedge fields. However, it exhibited certain irregular patterns at enhanced dynamic wedge angles. Dose monitor unit error exists only because of the overshoot phenomena and electronic delay in dose coincident and integrated circuits with a dependency on the dose rate and photon energy. Monitor unit errors are independent of the application of enhanced dynamic wedge. The existence of monitor unit error demands that the dose non-linearity of the linear accelerator dosimetry system be periodically tested, so as to avoid significant dosimetric errors.

  6. Radiation therapy imaging apparatus

    This patent describes a radiation therapy imaging apparatus for providing images in a patient being treated on a radiation therapy apparatus for verification and monitoring of patient positioning and verification of alignment and shaping of the radiation field of the radiation therapy apparatus. It comprises: a high-energy treatment head for applying a radiation dose to a patient positioned on a treatment table, and a gantry rotatable about an isocentric axis and carrying the treatment head for permitting the radiation dose to be applied to the patient from any of a range of angles about the isocentric axis; the radiation therapy imaging apparatus including a radiation therapy image detector which comprises a video camera mounted on the gantry diametrically opposite the treat head, an elongated light-excluding enclosure enveloping the camera to exclude ambient light from the camera, a fluoroscopic plate positioned on a distal end of the enclosure remote from the camera and aligned with the head to produce a fluoroscopic image in response to radiation applied from the head through the patient, mirror means in the enclosure and oriented for reflecting the image to the camera to permit monitoring on a viewing screen of the position of the radiation field in respect to the patient, and means for retracting at least the distal end of the enclosure from a position in which the fluoroscopic plate is disposed opposite the treatment head without disturbing the position of the camera on the gantry, so that the enclosure can be collapsed and kept from projecting under the treatment table when the patient is being positioned on the treatment table

  7. Pilot study of human recombinant interferon gamma and accelerated hyperfractionated thoracic radiation therapy in patients with unresectable stage IIIA/B nonsmall cell lung cancer

    Purpose: Gamma interferon has a wide range of properties, including the ability to sensitize solid tumor cells to the effects of ionizing radiation. The North Central Cancer Treatment Group has previously completed pilot studies of accelerated hyperfractionated thoracic radiation therapy (AHTRT) in patients with unresectable Stage IIIA/B nonsmall cell lung cancer (NSCLC). This Phase I study was designed to assess the toxicity of concomitant gamma interferon and AHTRT in a similar patient population. Methods and Materials: Between December 1991 and May 1992, 18 patients with unresectable Stage IIIA/B NSCLC were treated with daily gamma interferon (0.2 mg subcutaneously) concomitant with AHTRT (60 Gy given in 1.5 Gy twice daily fractions). All patients had an Eastern Cooperative Oncology Group performance status of 0 or 1 with weight loss < 5%. Eight patients had Stage IIIA and 10 had Stage IIIB disease. Results: Nine patients (50%) experienced severe, life-threatening, or fatal toxicities. Eight of the patients (44%) developed significant radiation pneumonitis, which was severe in six patients and fatal in two patients (11% treatment-related mortality). Two patients (11%) developed severe radiation esophagitis. With follow-up of 15-21 months, 2 patients are alive, and 16 have died. The median survival time and 1-year survival rate is 7.8 months and 38%, respectively. Conclusion: Gamma interferon appeared to sensitize normal lung tissue to the effects of radiation, as demonstrated by the high incidence of severe or fatal radiation pneumonitis. We do not recommend pursuing gamma interferon as a radiosensitizer in this setting

  8. Three-Year Outcomes of a Canadian Multicenter Study of Accelerated Partial Breast Irradiation Using Conformal Radiation Therapy

    Berrang, Tanya S., E-mail: tberrang@bccancer.bc.ca [British Columbia Cancer Agency-Vancouver Island, BC (Canada); University of British Columbia, BC (Canada); Olivotto, Ivo [British Columbia Cancer Agency-Vancouver Island, BC (Canada); University of British Columbia, BC (Canada); Kim, Do-Hoon [Juravinski Cancer Centre, Ontario (Canada); McMaster University, Ontario (Canada); Nichol, Alan [British Columbia Cancer Agency-Vancouver Centre, BC (Canada); University of British Columbia, BC (Canada); Cho, B.C. John [Princess Margaret Hospital, Ontario (Canada); University of Toronto, Ontario (Canada); Mohamed, Islam G. [British Columbia Cancer Agency-Southern Interior, BC (Canada); University of British Columbia, BC (Canada); Parhar, Tarnjit [British Columbia Cancer Agency-Vancouver Centre, BC (Canada); University of British Columbia, BC (Canada); Wright, J.R. [Juravinski Cancer Centre, Ontario (Canada); McMaster University, Ontario (Canada); Truong, Pauline [British Columbia Cancer Agency-Vancouver Island, BC (Canada); University of British Columbia, BC (Canada); Tyldesley, Scott [British Columbia Cancer Agency-Vancouver Centre, BC (Canada); University of British Columbia, BC (Canada); Sussman, Jonathan [Juravinski Cancer Centre, Ontario (Canada); McMaster University, Ontario (Canada); Wai, Elaine [British Columbia Cancer Agency-Vancouver Island, BC (Canada); University of British Columbia, BC (Canada); Whelan, Tim [Juravinski Cancer Centre, Ontario (Canada); McMaster University, Ontario (Canada)

    2011-12-01

    Purpose: To report 3-year toxicity, cosmesis, and efficacy of a multicenter study of external beam, accelerated partial breast irradiation (APBI) for early-stage breast cancer. Methods and Materials: Between March 2005 and August 2006, 127 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 involving five Canadian cancer centers. Women meeting predefined dose constraints were treated with APBI using 3 to 5 photon beams, delivering 35 to 38.5 Gy in 10 fractions, twice a day, over 1 week. Patients were assessed for treatment-related toxicities, cosmesis, and efficacy before APBI and at specified time points for as long as 3 years after APBI. Results: 104 women had planning computed tomography scans showing visible seromas, met dosimetric constraints, and were treated with APBI to doses of 35 Gy (n = 9), 36 Gy (n = 33), or 38.5 Gy (n = 62). Eighty-seven patients were evaluated with minimum 3-year follow-up after APBI. Radiation dermatitis, breast edema, breast induration, and fatigue decreased from baseline levels or stabilized by the 3-year follow-up. Hypopigmentation, hyperpigmentation, breast pain, and telangiectasia slightly increased from baseline levels. Most toxicities at 3 years were Grade 1. Only 1 patient had a Grade 3 toxicity with telangiectasia in a skin fold inside the 95% isodose. Cosmesis was good to excellent in 86% (89/104) of women at baseline and 82% (70/85) at 3 years. The 3-year disease-free survival was 97%, with only one local recurrence that occurred in a different quadrant away from the treated site and two distant recurrences. Conclusions: At 3 years, toxicity and cosmesis were acceptable, and local control and disease-free survival were excellent, supporting continued accrual to randomized APBI trials.

  9. Fractionated radiation therapy after Strandqvist

    Models for predicting the total dose required to produce tolerable normal-tissue damage in radiation therapy are becoming less empirical, more realistic, and more specific for different tissue reactions. The progression is described from the 'cube root law', through STRANDQVIST'S well known graph to NSD, TDF and CRE and more recently to biologically based time factors and linear-quadratic dose-response curves. New applications of the recent approach are reviewed together with their implications for non-standard fractionation in radiation therapy. It is concluded that accelerated fractionation is an important method to be investigated, as well as hyperfractionation; and that more data are required about the proliferation rates of clonogenic cells in human tumours. (orig.)

  10. Five-Year Outcomes, Cosmesis, and Toxicity With 3-Dimensional Conformal External Beam Radiation Therapy to Deliver Accelerated Partial Breast Irradiation

    Purpose: To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT). Methods and Materials: 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor. Results: The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups. Conclusions: APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with conventional WBI

  11. Electron accelerators for radiation sterilization

    Industrial radiation processes using high power electron accelerators are attractive because the throughput rates are very high and the treatment costs per unit of product are often competitive with more conventional chemical processes. The utilization of energy in e-beam processing is more efficient than typical thermal processing. The use of volatiles or toxic chemicals can be avoided. Strict temperature or moisture controls may not be needed. Irradiated materials are usable immediately after processing. These capabilities are unique in that beneficial changes can be induced rapidly in solid materials and preformed products. In recent years, e-beam accelerators have emerged as the preferred alternative for industrial processing as they offer advantages over isotope radiation sources, such as (a) increased public acceptance since the storage, transport and disposal of radioactive material is not an issue; (b) the ability to hook up with the manufacturing process for in-line processing; (c) higher dose rates resulting in high throughputs. During the 1980s and 1990s, accelerator manufacturers dramatically increased the beam power available for high energy equipment. This effort was directed primarily at meeting the demands of the sterilization industry. During this era, the perception that bigger (higher power, higher energy) was always better prevailed, since the operating and capital costs of accelerators did not increase with power and energy as fast as the throughput. High power was needed to maintain low unit costs for the treatment. During the late 1980s and early 1990s, advances in e-beam technology produced new high energy, high power e-beam accelerators suitable for use in sterilization on an industrial scale. These newer designs achieved high levels of reliability and proved to be competitive with gamma sterilization by 60Co and fumigation with EtO. In parallel, technological advances towards 'miniaturization' of accelerators also made it possible to

  12. Involved Node Radiation Therapy

    Maraldo, Maja V; Aznar, Marianne C; Vogelius, Ivan R;

    2012-01-01

    PURPOSE: The involved node radiation therapy (INRT) strategy was introduced for patients with Hodgkin lymphoma (HL) to reduce the risk of late effects. With INRT, only the originally involved lymph nodes are irradiated. We present treatment outcome in a retrospective analysis using this strategy ...

  13. External Radiation Therapy

    Full Text Available ... predict when or even if the remaining cancer cells will become active again. Christopher Wood, M.D.: It's at the ten-year mark where the differences between success rates with radical prostatectomy and radiation therapy become evident,and if you're not going ...

  14. Principles of radiation therapy

    This chapter reviews (a) the natural history of metastatic bone disease in general terms and as it impacts on the use of radiation as therapy; (b) the clinical and radiographic evaluations used to guide the application of irradiation; and (c) the methods, results, and toxicities of various techniques of irradiation

  15. External Radiation Therapy

    Full Text Available ... prostate or when the patient is older the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms ... different types. There's what we call external beam treatment, which is given from an x-ray machine, ...

  16. A Survey of Hadron Therapy Accelerator Technologies

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy

  17. A Survey of Hadron Therapy Accelerator Technologies.

    PEGGS,S.; SATOGATA, T.; FLANZ, J.

    2007-06-25

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy.

  18. Intraoperative Radiation Therapy in Early Breast Cancer Using a Linear Accelerator Outside of the Operative Suite: An “Image-Guided” Approach

    Hanna, Samir Abdallah, E-mail: samir.hanna@hsl.org.br [Department of Radiation Oncology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Simões Dornellas de Barros, Alfredo Carlos; Martins de Andrade, Felipe Eduardo; Barbosa Bevilacqua, Jose Luiz [Department of Mastology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Morales Piato, José Roberto [Department of Mastology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Department of Gynecology, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo (Brazil); Lopes Pelosi, Edilson [Department of Radiation Oncology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Martella, Eduardo [Department of Radiation Oncology, Hospital Perola Byington, Sao Paulo (Brazil); Fernandes da Silva, João Luis [Department of Radiation Oncology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Andrade Carvalho, Heloisa de [Department of Radiation Oncology, Hospital Sirio-Libanes, Sao Paulo (Brazil); Department of Radiology and Oncology, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo (Brazil)

    2014-08-01

    Purpose: To present local control, complications, and cosmetic outcomes of intraoperative radiation therapy (IORT) for early breast cancer, as well as technical aspects related to the use of a nondedicated linear accelerator. Methods and Materials: This prospective trial began in May of 2004. Eligibility criteria were biopsy-proven breast-infiltrating ductal carcinoma, age >40 years, tumor <3 cm, and cN0. Exclusion criteria were in situ or lobular types, multicentricity, skin invasion, any contraindication for surgery and/or radiation therapy, sentinel lymph node involvement, metastasis, or another malignancy. Patients underwent classic quadrantectomy with intraoperative sentinel lymph node and margins evaluation. If both free, the patient was transferred from operative suite to linear accelerator room, and IORT was delivered (21 Gy). Primary endpoint: local recurrence (LR); secondary endpoints: toxicities and aesthetics. Quality assurance involved using a customized shield for chest wall protection, applying procedures to minimize infection caused by patient transportation, and using portal films to check collimator-shield alignment. Results: A total of 152 patients were included, with at least 1 year follow-up. Median age (range) was 58.3 (40-85.4) years, and median follow-up time was 50.7 (12-110.5) months. The likelihood of 5-year local recurrence was 3.7%. There were 3 deaths, 2 of which were cancer related. The Kaplan-Meier 5-year actuarial estimates of overall, disease-free, and local recurrence-free survivals were 97.8%, 92.5%, and 96.3%, respectively. The overall incidences of acute and late toxicities were 12.5% and 29.6%, respectively. Excellent, good, fair, and bad cosmetic results were observed in 76.9%, 15.8%, 4.3%, and 2.8% of patients, respectively. Most treatments were performed with a 5-cm collimator, and in 39.8% of the patients the electron-beam energy used was ≥12 MeV. All patients underwent portal film evaluation, and the shielding was

  19. Intraoperative Radiation Therapy in Early Breast Cancer Using a Linear Accelerator Outside of the Operative Suite: An “Image-Guided” Approach

    Purpose: To present local control, complications, and cosmetic outcomes of intraoperative radiation therapy (IORT) for early breast cancer, as well as technical aspects related to the use of a nondedicated linear accelerator. Methods and Materials: This prospective trial began in May of 2004. Eligibility criteria were biopsy-proven breast-infiltrating ductal carcinoma, age >40 years, tumor <3 cm, and cN0. Exclusion criteria were in situ or lobular types, multicentricity, skin invasion, any contraindication for surgery and/or radiation therapy, sentinel lymph node involvement, metastasis, or another malignancy. Patients underwent classic quadrantectomy with intraoperative sentinel lymph node and margins evaluation. If both free, the patient was transferred from operative suite to linear accelerator room, and IORT was delivered (21 Gy). Primary endpoint: local recurrence (LR); secondary endpoints: toxicities and aesthetics. Quality assurance involved using a customized shield for chest wall protection, applying procedures to minimize infection caused by patient transportation, and using portal films to check collimator-shield alignment. Results: A total of 152 patients were included, with at least 1 year follow-up. Median age (range) was 58.3 (40-85.4) years, and median follow-up time was 50.7 (12-110.5) months. The likelihood of 5-year local recurrence was 3.7%. There were 3 deaths, 2 of which were cancer related. The Kaplan-Meier 5-year actuarial estimates of overall, disease-free, and local recurrence-free survivals were 97.8%, 92.5%, and 96.3%, respectively. The overall incidences of acute and late toxicities were 12.5% and 29.6%, respectively. Excellent, good, fair, and bad cosmetic results were observed in 76.9%, 15.8%, 4.3%, and 2.8% of patients, respectively. Most treatments were performed with a 5-cm collimator, and in 39.8% of the patients the electron-beam energy used was ≥12 MeV. All patients underwent portal film evaluation, and the shielding was

  20. Radiation therapy facilities in the United States

    Purpose: About half of all cancer patients in the United States receive radiation therapy as a part of their cancer treatment. Little is known, however, about the facilities that currently deliver external beam radiation. Our goal was to construct a comprehensive database of all radiation therapy facilities in the United States that can be used for future health services research in radiation oncology. Methods and Materials: From each state's health department we obtained a list of all facilities that have a linear accelerator or provide radiation therapy. We merged these state lists with information from the American Hospital Association (AHA), as well as 2 organizations that audit the accuracy of radiation machines: the Radiologic Physics Center (RPC) and Radiation Dosimetry Services (RDS). The comprehensive database included all unique facilities listed in 1 or more of the 4 sources. Results: We identified 2,246 radiation therapy facilities operating in the United States as of 2004-2005. Of these, 448 (20%) facilities were identified through state health department records alone and were not listed in any other data source. Conclusions: Determining the location of the 2,246 radiation facilities in the United States is a first step in providing important information to radiation oncologists and policymakers concerned with access to radiation therapy services, the distribution of health care resources, and the quality of cancer care

  1. Five-Year Outcomes, Cosmesis, and Toxicity With 3-Dimensional Conformal External Beam Radiation Therapy to Deliver Accelerated Partial Breast Irradiation

    Rodríguez, Núria, E-mail: nrodriguez@parcdesalutmar.cat [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Universidad Pompeu Fabra, Barcelona (Spain); Sanz, Xavier [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Universidad Pompeu Fabra, Barcelona (Spain); Dengra, Josefa [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Foro, Palmira [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Universidad Pompeu Fabra, Barcelona (Spain); Membrive, Ismael; Reig, Anna [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Quera, Jaume [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Universidad Pompeu Fabra, Barcelona (Spain); Fernández-Velilla, Enric; Pera, Óscar; Lio, Jackson; Lozano, Joan [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Algara, Manuel [Department of Radiation Oncology, Hospital de la Esperanza, Parc de Salut MAR, Barcelona (Spain); Universidad Pompeu Fabra, Barcelona (Spain)

    2013-12-01

    Purpose: To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT). Methods and Materials: 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor. Results: The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P<.01). Late skin toxicity was no worse than grade 2 in either group, without significant differences between the 2 groups. In the ipsilateral breast, the areas that received the highest doses (ie, the boost or quadrant) showed the greatest loss of elasticity. WBI resulted in a greater loss of elasticity in the high-dose area compared with APBI (P<.05). Physician assessment showed that >75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups. Conclusions: APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with

  2. Microbeam radiation therapy

    Laissue, Jean A.; Lyubimova, Nadia; Wagner, Hans-Peter; Archer, David W.; Slatkin, Daniel N.; Di Michiel, Marco; Nemoz, Christian; Renier, Michel; Brauer, Elke; Spanne, Per O.; Gebbers, Jan-Olef; Dixon, Keith; Blattmann, Hans

    1999-10-01

    The central nervous system of vertebrates, even when immature, displays extraordinary resistance to damage by microscopically narrow, multiple, parallel, planar beams of x rays. Imminently lethal gliosarcomas in the brains of mature rats can be inhibited and ablated by such microbeams with little or no harm to mature brain tissues and neurological function. Potentially palliative, conventional wide-beam radiotherapy of malignant brain tumors in human infants under three years of age is so fraught with the danger of disrupting the functional maturation of immature brain tissues around the targeted tumor that it is implemented infrequently. Other kinds of therapy for such tumors are often inadequate. We suggest that microbeam radiation therapy (MRT) might help to alleviate the situation. Wiggler-generated synchrotron x-rays were first used for experimental microplanar beam (microbeam) radiation therapy (MRT) at Brookhaven National Laboratory's National Synchrotron Light Source in the early 1990s. We now describe the progress achieved in MRT research to date using immature and adult rats irradiated at the European Synchrotron Radiation Facility in Grenoble, France, and investigated thereafter at the Institute of Pathology of the University of Bern.

  3. Dose linearity and uniformity of Siemens ONCOR impression plus linear accelerator designed for step-and-shoot intensity-modulated radiation therapy

    For step-and-shoot type delivery of intensity-modulated radiation therapy (IMRT), beam stability characteristics during the first few monitor units need to be investigated to ensure the planned dose delivery. This paper presents the study done for Siemens ONCOR impression plus linear accelerator before commissioning it for IMRT treatment. The beam stability for 6 and 15 MV in terms of dose monitor linearity, monitor unit stability and beam uniformity is investigated in this work. Monitor unit linearity is studied using FC65G chamber for the range 1-100 MU. The dose per MU is found to be linear for small monitor units down to 1 MU for both 6 and 15 MV beams. The monitor unit linearity is also studied with portal imaging device for the range 1-20 MU for 6 MV beam. The pixel values are within ±1σ confidence level up to 2 MU; for 1 MU, the values are within ±2σ confidence level. The flatness and symmetry analysis is done for both energies in the range of 1-10 MU with Kodak diagnostic films. The flatness and symmetry are found to be within ±3% up to 2 MU for 6 MV and up to 3 MU for 15 MV. (author)

  4. Contribution to the examination of the radiation field of medical linear accelerator SL 75-20 to therapy of tumors

    The vast majority of radiological studies indicate that the Do values for different mammalian cells, irradiated with X- or γ-rays, cluster quite closely around a value of about 1,3 Gy. There are a number of mathematical ways to define the shape of survival curves. All of these are based on the concept of the random nature of energy deposition by radiation. As the energy is increased above 4 MeV, it is possible to concentrate more energy in the tumor than in the surrounding tissues. The analysis showed that an energy of about 20-25 MeV is optimum. The concept of therapeutic ratio is represented by the percentage of patients who will develop complications as a function of dose. It has been found empirically that radiation has been used to treat patients with malignant disease, that fractionating the radiation treatment, so that it is given over a period of weeks, results in a better therapeutic ratio for most tumors than giving the treatment of a single dose. To illustrate the procedure, we have selected at random 40 patients with cancer of the cervix and we have examined their status via the time with their life lines. From the diagram we note that slope of the survival curves in the recent era is identical to that of the normal population. This means that, if a woman reaches a point 6 to 8 years after treatment and is still disease free, she will have the same life expectancy as a woman of the same age, in the normal population. (author)

  5. Principles of radiation therapy

    Radiation oncology now represents the integration of knowledge obtained over an 80-year period from the physics and biology laboratories and the medical clinic. Such integration is recent; until the supervoltage era following World War II, the chief developments in these three areas for the most part were realized independently. The physics and engineering laboratories have now developed a dependable family of sources of ionizing radiations that can be precisely directed at tumor volumes at various depths within the body. The biology laboratory has provided the basic scientific support underlying the intensive clinical experience and currently is suggesting ways of using ionizing radiations more effectively, such as modified fractionation schedules relating to cell cycle kinetics and the use of drugs and chemicals as modifiers of radiation response and normal tissue reaction. The radiation therapy clinic has provided the patient stratum on which the acute and chronic effects of irradiation have been assessed, and the patterns of treatment success and failure identified. The radiation therapist has shared with the surgeon and medical oncologist the responsibility for clarifying the natural history of a large number of human neoplasms, and through such clarifications, has developed more effective treatment strategies. Several examples of this include the improved results in the treatment of Hodgkin's disease, squamous cell carcinoma of the cervix, seminoma, and epithelial neoplasms of the upper aerodigestive tract

  6. Concurrent chemo-irradiation using accelerated concomitant boost radiation therapy in loco-regionally advanced head and neck squamous cell carcinomas

    Vivek R

    2006-01-01

    Full Text Available Purpose: To investigate the feasibility of combining concomitant boost-accelerated radiation regimen (ACB with full-dose mono-chemotherapy using cisplatin and to assess its local response and acute toxicity patterns in patients with advanced loco-regional head and neck squamous cell carcinoma (HNSCC. Materials and Methods: Between July 2004 and August 2005, a pilot study involving 27 patients with stage III to IVB (AJCC-6th HNSCC of the oropharynx, hypopharynx and larynx who met the eligibility criteria was undertaken. Twenty-four of these patients (median age - 53 years were analyzable. The radiation dose was 72 Gy in 42 fractions over 6 weeks, delivered in one daily fraction of 1.8 Gy during the first 3.5 weeks and two fractions per day, 1.8 Gy and 1.5 Gy boost-separated by> 6 h interval, during the last 2.5 weeks. cisplatin, 100 mg/m2, was given in intravenous (i.v. infusion on day 1 and day 22. Tumor and clinical status were assessed and acute toxicities were graded. Results: Out of 27 patients, 24 patients received both radiation and chemotherapy as per protocol and were available for analysis. The loco-regional response rates were as follows: an overall response of 95.8% (23 patients, a complete response of 79.1% (19 patients, a partial response of 16.7% (4 patients and progressive disease in 4.2% (1 patient. Dysphagia, nausea, vomiting and bone marrow suppression were the most common side effects and were associated with cisplatin administration. One patient (3.7% died of complications (pneumonia and sepsis, 3 patients (12.5% had acute grade 4 toxicity and 21 patients (87.5% had acute grade 3 (17 patients or grade 2 (4 patients toxicity. Conclusion: This data shows that it is feasible to combine ACB and full-dose mono-chemotherapy using cisplatin with manageable, although substantial, toxicity. The compliance to therapy was high and the loco-regional response achieved compared favorably with ACB alone or other concurrent chemoradiation

  7. Phase 2 Study of Accelerated Hypofractionated Thoracic Radiation Therapy and Concurrent Chemotherapy in Patients With Limited-Stage Small-Cell Lung Cancer

    Purpose: To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting. Methods and Materials: Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 to 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate. Results: Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation. Conclusion: Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC

  8. Phase 2 Study of Accelerated Hypofractionated Thoracic Radiation Therapy and Concurrent Chemotherapy in Patients With Limited-Stage Small-Cell Lung Cancer

    Xia, Bing [Department of Radiation Oncology, Shanghai Cancer Center, Fudan University, Shanghai (China); Department of Radiation Oncology, Hangzhou Cancer Hospital, Hangzhou (China); Hong, Ling-Zhi [Department of Oncology, Nanjing First Hospital, Nanjing Medical University, Nanjing (China); Cai, Xu-Wei; Zhu, Zheng-Fei; Liu, Qi; Zhao, Kuai-Le; Fan, Min; Mao, Jing-Fang; Yang, Huan-Jun; Wu, Kai-Liang [Department of Radiation Oncology, Shanghai Cancer Center, Fudan University, Shanghai (China); Fu, Xiao-Long, E-mail: xlfu1964@hotmail.com [Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai (China)

    2015-03-01

    Purpose: To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting. Methods and Materials: Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 to 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate. Results: Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation. Conclusion: Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.

  9. Study on external beam radiation therapy

    Kim, Mi Sook; Yoo, Seoung Yul; Yoo, Hyung Jun; Ji, Young Hoon; Lee, Dong Han; Lee, Dong Hoon; Choi, Mun Sik; Yoo, Dae Heon; Lee, Hyo Nam; Kim, Kyeoung Jung

    1999-04-01

    To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT.

  10. Study on external beam radiation therapy

    To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT

  11. Accelerated Partial Breast Irradiation Is Safe and Effective Using Intensity-Modulated Radiation Therapy in Selected Early-Stage Breast Cancer

    Lewin, Alan A., E-mail: alanl@baptisthealth.net [Department of Radiation Oncology, Baptist Hospital of Miami, Miami, FL (United States); Derhagopian, Robert [Department of Surgery, Baptist Hospital of Miami, Miami, FL (United States); Saigal, Kunal; Panoff, Joseph E. [Department of Radiation Oncology, University of Miami, Miami, FL (United States); Abitbol, Andre; Wieczorek, D. Jay; Mishra, Vivek [Department of Radiation Oncology, Baptist Hospital of Miami, Miami, FL (United States); Reis, Isildinha; Ferrell, Annapoorna [Division of Biostatistics, University of Miami, Miami, FL (United States); Moreno, Lourdes [Department of Radiation Oncology, Baptist Hospital of Miami, Miami, FL (United States); Takita, Cristiane [Department of Radiation Oncology, University of Miami, Miami, FL (United States)

    2012-04-01

    Purpose: To report the feasibility, toxicity, cosmesis, and efficacy of using intensity-modulated radiation therapy (IMRT) with respiratory gating to deliver accelerated partial breast irradiation (APBI) in selected Stage I/II breast cancer after breast-conserving surgery. Methods and Materials: Eligible patients with node-negative Stage I/II breast cancer were prospectively enrolled in an institutional review board approved protocol to receive APBI using IMRT after breast-conserving surgery. The target volume was treated at 3.8 Gy/fraction twice daily for 5 days, to a total dose of 38 Gy. Results: Thirty-six patients were enrolled for a median follow-up time of 44.8 months. The median tumor size was 0.98 cm (range, 0.08-3 cm). The median clinical target volume (CTV) treated was 71.4 cc (range, 19-231 cc), with the mean dose to the CTV being 38.96 Gy. Acute toxicities included Grade 1 erythema in 44% of patients and Grade 2 in 6%, Grade 1 hyperpigmentation in 31% of patients and Grade 2 in 3%, and Grade 1 breast/chest wall tenderness in 14% of patients. No Grade 3/4 acute toxicities were observed. Grade 1 and 2 late toxicities as edema, fibrosis, and residual hyperpigmentation occurred in 14% and 11% of patients, respectively; Grade 3 telangiectasis was observed in 3% of patients. The overall cosmetic outcome was considered 'excellent' or 'good' by 94% of patients and 97% when rated by the physician, respectively. The local control rate was 97%; 1 patient died of a non-cancer-related cause. Conclusions: APBI can be safely and effectively administered using IMRT. In retrospective analysis, IMRT enabled the achievement of normal tissue dose constraints as outlined by Radiation Therapy Oncology Group 04-13/NSABP B-13 while providing excellent conformality for the CTV. Local control and cosmesis have remained excellent at current follow-up, with acceptable rates of acute/late toxicities. Our data suggest that cosmesis is dependent on target volume

  12. Accelerated Partial Breast Irradiation Is Safe and Effective Using Intensity-Modulated Radiation Therapy in Selected Early-Stage Breast Cancer

    Purpose: To report the feasibility, toxicity, cosmesis, and efficacy of using intensity-modulated radiation therapy (IMRT) with respiratory gating to deliver accelerated partial breast irradiation (APBI) in selected Stage I/II breast cancer after breast-conserving surgery. Methods and Materials: Eligible patients with node-negative Stage I/II breast cancer were prospectively enrolled in an institutional review board approved protocol to receive APBI using IMRT after breast-conserving surgery. The target volume was treated at 3.8 Gy/fraction twice daily for 5 days, to a total dose of 38 Gy. Results: Thirty-six patients were enrolled for a median follow-up time of 44.8 months. The median tumor size was 0.98 cm (range, 0.08–3 cm). The median clinical target volume (CTV) treated was 71.4 cc (range, 19–231 cc), with the mean dose to the CTV being 38.96 Gy. Acute toxicities included Grade 1 erythema in 44% of patients and Grade 2 in 6%, Grade 1 hyperpigmentation in 31% of patients and Grade 2 in 3%, and Grade 1 breast/chest wall tenderness in 14% of patients. No Grade 3/4 acute toxicities were observed. Grade 1 and 2 late toxicities as edema, fibrosis, and residual hyperpigmentation occurred in 14% and 11% of patients, respectively; Grade 3 telangiectasis was observed in 3% of patients. The overall cosmetic outcome was considered “excellent” or “good” by 94% of patients and 97% when rated by the physician, respectively. The local control rate was 97%; 1 patient died of a non–cancer-related cause. Conclusions: APBI can be safely and effectively administered using IMRT. In retrospective analysis, IMRT enabled the achievement of normal tissue dose constraints as outlined by Radiation Therapy Oncology Group 04-13/NSABP B-13 while providing excellent conformality for the CTV. Local control and cosmesis have remained excellent at current follow-up, with acceptable rates of acute/late toxicities. Our data suggest that cosmesis is dependent on target volume size

  13. [Problems after radiation therapy].

    Karasawa, Kumiko

    2014-01-01

    The rate of severe late adverse effects has decreased with the highly accurate administration of radiation therapy; however, the total number of patients who suffer from late effects has not decreased because of the increased total number of patients and better survival rates. Late adverse effects, occurring more than a few months after irradiation, include the extension and collapse of capillaries, thickening of the basement membrane, and scarring of tissue due to loss of peripheral vessels. The main causes of these late effects are the loss of stromal cells and vascular injury. This is in contrast to early reactions, which occur mainly due to the reorganization of slow-growing non-stem cell renewal systems such as the lung, kidney, heart, and central nervous system. In addition, the patient's quality of life is impaired if acute reactions such as mouth or skin dryness are not alleviated. Most adverse effects are radiation dose dependent, and the thresholds differ according to the radiosensitivity of each organ. These reactions occur with a latency period of a few months to more than 10 years. Understanding the clinical and pathological status, through discussion with radiation oncologists, is the essential first step. Some of the late effects have no effective treatment, but others can be treated by steroids or hyperbaric oxygen therapy. An appropriate decision is important. PMID:24423950

  14. Intracoronary radiation therapy

    Moon, Dae Hyuk; Oh, Seung Jun; Lee, Hee Kung; Park, Seong Wook; Hong, Myeong Ki [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of); Bom, Hee Seung [College of Medicine, Chonnam National Univ., Kwangju (Korea, Republic of)

    2001-07-01

    Restenosis remains a major limitation of percutaneous coronary interventions. Numerous Studies including pharmacological approaches and new devices failed to reduce restenosis rate except coronary stenting. Since the results of BENESTENT and STRESS studies came out, coronary stenting has been the most popular interventional strategy in the various kinds of coronary stenotic lesions, although the efficacy of stending was shown only in the discrete lesion of the large coronary artery. The widespread use of coronary stending has improved the early and late outcomes after coronary intervention, but it has also led to a new and serious problem, e.g., in-stent restenosis. Intravascular radiation for prevention of restenosis is a new technology in the field of percutaneous coronary intervention. Recent animal experiments and human trials have demonstrated that local irradiation, in conjunction with coronary interventions, substantially diminished the rate of restenosis. This paper reviews basic radiation biology of intracoronary radiation and its role in the inhibition of restenosis. The current status of intracoronary radiation therapy using Re-188 liquid balloon is also discussed.

  15. Radiation Therapy for Skin Cancer

    ... skin cells called melanocytes that produce skin color ( melanin ). Radiation therapy is used mostly for melanomas that ... in addition to surgery, chemotherapy or biologic therapy. Hair Epidermis Dermis Subcutaneous Hair Follicle Vein Artery © ASTRO ...

  16. About radiation therapy

    Explained are the history and outline of technology in radiation therapy (RT), characteristics of dose distribution of major radiations in RT and significance of biological effective dose (BED) from aspects of radiation oncology and therapeutic prediction. The history is described from the first X-ray RT documented in 1896 to the latest (1994) RT with National Institute of Radiological Sciences (NIRS) carbon beam for tumors in trunk. X-ray RT has aimed to make the energy high because target tumors are generally present deep in the body and an ideal RT, the intensity modulated RT, has been developed to assure the desirable dose distribution (or, dose-volume histogram) based on precise planning with X-CT and computing. Low energy gamma ray emitted from radioisotopes provides also an ideal RT mean because of its excellent focusing to the internal target; however, problems remain of invasion and long lodging of the isotope in the body. Heavy ion RT is conducted on the planning on X-CT image and computation utilizing Bragg's principle and is superior for minimizing the exposure of normal, non-cancerous tissues. Boron neutron capture therapy is a promising RT as the local control is always possible at 10B ratio of the lesion/normal tissue >2.5, which is measurable by PET with 18F-boronophenylalanine. In the current oncology, BED is estimated by the linear quadratic model, α(nd)+β(nd)2, where d is a total irradiation dose and n, number of fractionation, and is a planning basis for the effect prediction in RT above. Physical problems in future involve the system development of more efficient dose focusing and convenient dose impartation, and development of more easily operable system and cost reduction is awaited. (R.T.)

  17. Radiation Therapy for Breast Cancer

    ... therapy. Ask your doctor for more information. For women undergoing reconstruction, post- mastectomy radiation may affect your options for reconstruction or the cosmetic outcome. Discuss with your surgeon and radiation oncologist ...

  18. Stereotactic body radiation therapy

    Comprehensive an up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. Examines in detail retrospective studies and prospective clinical trials for various organ sites from around the world. Written by world-renowned experts in SBRT from North America, Asia and Europe. Stereotactic body radiation therapy (SBRT) has emerged as an innovative treatment for various primary and metastatic cancers, and the past five years have witnessed a quantum leap in its use. This book provides a comprehensive and up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. It will serve as a detailed resource for this rapidly developing treatment modality. The organ sites covered include lung, liver, spine, pancreas, prostate, adrenal, head and neck, and female reproductive tract. Retrospective studies and prospective clinical trials on SBRT for various organ sites from around the world are examined, and toxicities and normal tissue constraints are discussed. This book features unique insights from world-renowned experts in SBRT from North America, Asia, and Europe. It will be necessary reading for radiation oncologists, radiation oncology residents and fellows, medical physicists, medical physics residents, medical oncologists, surgical oncologists, and cancer scientists.

  19. Stereotactic body radiation therapy

    Lo, Simon S. [Univ. Hospitals Seidman Cancer Center, Cleveland, OH (United States). Dept. of Radiation Oncology; Case Western Reserve Univ., Cleveland, OH (United States). Case Comprehensive Cancer Center; Teh, Bin S. [The Methodist Hospital Cancer Center and Research Institute, Houston, TX (United States). Weill Cornell Medical College; Lu, Jiade J. [National Univ. of Singapore (Singapore). Dept. of Radiation Oncology; Schefter, Tracey E. (eds.) [Colorado Univ., Aurora, CO (United States). Dept. of Radiation Oncology

    2012-11-01

    Comprehensive an up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. Examines in detail retrospective studies and prospective clinical trials for various organ sites from around the world. Written by world-renowned experts in SBRT from North America, Asia and Europe. Stereotactic body radiation therapy (SBRT) has emerged as an innovative treatment for various primary and metastatic cancers, and the past five years have witnessed a quantum leap in its use. This book provides a comprehensive and up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. It will serve as a detailed resource for this rapidly developing treatment modality. The organ sites covered include lung, liver, spine, pancreas, prostate, adrenal, head and neck, and female reproductive tract. Retrospective studies and prospective clinical trials on SBRT for various organ sites from around the world are examined, and toxicities and normal tissue constraints are discussed. This book features unique insights from world-renowned experts in SBRT from North America, Asia, and Europe. It will be necessary reading for radiation oncologists, radiation oncology residents and fellows, medical physicists, medical physics residents, medical oncologists, surgical oncologists, and cancer scientists.

  20. The physics of radiation therapy

    Khan, Faiz M

    2009-01-01

    Dr. Khan's classic textbook on radiation oncology physics is now in its thoroughly revised and updated Fourth Edition. It provides the entire radiation therapy team—radiation oncologists, medical physicists, dosimetrists, and radiation therapists—with a thorough understanding of the physics and practical clinical applications of advanced radiation therapy technologies, including 3D-CRT, stereotactic radiotherapy, HDR, IMRT, IGRT, and proton beam therapy. These technologies are discussed along with the physical concepts underlying treatment planning, treatment delivery, and dosimetry. This Fourth Edition includes brand-new chapters on image-guided radiation therapy (IGRT) and proton beam therapy. Other chapters have been revised to incorporate the most recent developments in the field. This edition also features more than 100 full-color illustrations throughout.

  1. Recent trends in particle accelerator radiation safety

    The use of particle accelerators in applied and research activities continues to expand, bringing new machines with higher energy and current capabilities which create radiation safety problems not commonly encountered before. An overview is given of these increased ionizing radiation hazards, along with a discussion of some of the new techniques required in evaluating and controlling them. A computer search of the literature provided a relatively comprehensive list of publications describing accelerator radiation safety problems and related subjects

  2. Prognostic significance of proliferation associated antigens (PCNA, Ki-67) and p53-expression in inoperable head and neck cancer after accelerated split-course radiation therapy

    Purpose: To determine whether the immunohistochemical (IHC) expression of proliferation associated antigens (Proliferating Cell Nuclear Antigen [PCNA], Ki-67) and the nuclear p53 reactivity are predictive for overall-survival (OS) and relapse-free-survival (RFS) in patients (pts) with inoperable squamous cell carcinoma of the head and neck region (SCC H and N) after accelerated split-course radiation therapy (RT) with and without chemotherapy (ChT). Materials and Methods: Between 10/89 and 9/93, 87 pts with biopsy proven SCC H and N (80 male, 7 female, median age 52 years [range, 23-65 years]) were randomly allocated to RT alone or simultaneous RT/ChT as part of a multicenter trial. All pts had inoperable lesions in AJCC (1988) stage III (7 pts, 8%) and IV (80 pts, 92%). Primaries were located in the oral cavity (19 pts, 22%), oropharynx (38 pts, 44%) and hypopharynx (30 pts, 34%). RT consisted of 3 cycles of accelerated fractionation (180 cGy bid, total dose 7020 cGy/51 days). Scheduled split between cycles was 10 days. ChT consisted of cis-DDP, 60 mg/m2, 5-FU, 350 mg/m2, Leucovorin (LV) 50 mg/m2 iv bolus on day 2 and 5-FU, 350 mg/m2/24 h and LV 100 mg/m2/24 h ci on days 3-5. ChT was repeated on days 22 and 44. Routinely processed paraffin embedded sections were IHC-stained using the monoclonal antibodies PC 10, MIB1 and DO7 for detection of PCNA, Ki-67 antigen and p53 oncoprotein. Percentage of positive nuclei per 1000 tumor cells were given as Labeling Index (LI). In addition, tumor volume (TV) and percentage of necrosis were measured using CT-data. Median follow-up was 3.5 years (range 1.5-5 years). Results: OS and RFS were 39% and 44% after 3 years, respectively. In univariate analysis TV (>125 ml: 5% OS vs. ≤125 ml: 54% OS, p55years: 66% OS vs. ≤55years: 23% OS, p=.0025), PCNA-LI (LI>20%: 50% OS vs. LI≤20%: 31% OS, p=.0146),MIB1-LI (LI>20%: 55% OS vs. LI≤20%: 23% OS, p=.0344) and additional ChT (RT/ChT: 41% OS vs. RT: 27% OS, p=.0258) had a

  3. Accelerators for the advanced radiation technology project

    Ion beam irradiation facilities are now under construction for the advanced radiation technology (ART) project in Takasaki Radiation Chemistry Research Establishment of (Japan Atomic Energy Research Institute) JAERI. The project is intended to make an effective use of ion beams, especially ion beams, in the research field of radiation application technology. The TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities include four ion accelerators to produce almost all kinds of energetic ions in the periodic table. The facilities are also provided with several advanced irradiation means and act as very powerful accelerator complex for material development. Specifically, this report presents an outline of the ART project, features of TIARA as accelerator facilities dedicated to material development, the AVF cyclotron under construction (Sumitomo Heavy Industries, Ltd., Model 930), tandem accelerator, microbeam, and experimental instruments used. (N.K.)

  4. Radiation therapy in palliative care

    Radiation therapy is a valuable treatment for palliation of local symptoms with consistently high response rates in the relief and control of bone pain, neurological symptom, obstructive symptoms, and tumor hemorrhage. Over than 80% of patients who developed bone metastasis and superior vena cava syndrome obtained symptom relief by radiation therapy. Radiation therapy is also well established as an effective treatment for brain metastasis, improving symptoms and preventing progressive neurological deficits, and recently stereotactic irradiation had became a alternative treatment of surgery for small metastatic brain tumors. Both radiation therapy and surgery are effective in the initial treatment of malignant spinal cord compression syndrome, and no advantages of surgery over radiation therapy has been demonstrated in published series when patients have a previously conformed diagnosis of malignant disease and no evidence of vertebral collapse. The outcome of treatment depends primarily upon the speed of diagnosis and neurological status at initiation of treatment. It is very important to start radiation therapy before patient become non-ambulant. Low irradiation dose and short treatment period of palliative radiation therapy can minimize disruption and acute morbidity for the patients with advanced cancer with enabling control of symptoms and palliative radiation therapy is applicable to the patient even in poor general condition. (author)

  5. Recircular accelerator to proton ocular therapy

    Rabelo, Luisa A.; Campos, Tarcisio P.R., E-mail: luisarabelo88@gmail.com, E-mail: tprcampos@pq.cnpq.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2013-07-01

    Proton therapy has been used for the treatment of Ocular Tumors, showing control in most cases as well as conservation of the eyeball, avoiding the enucleation. The protons provide higher energetic deposition in depth with reduced lateral spread, compared to the beam of photons and electrons, with characteristic dose deposition peak (Bragg peak). This technique requires large particle accelerators hampering the deployment a Proton Therapy Center in some countries due to the need for an investment of millions of dollars. This study is related to a new project of an electromagnetic unit of proton circular accelerator to be coupled to the national radiopharmaceutical production cyclotrons, to attend ocular therapy. This project evaluated physical parameters of proton beam circulating through classical and relativistic mechanical formulations and simulations based on an ion transport code in electromagnetic fields namely CST (Computer Simulation Technology). The structure is differentiated from other circular accelerations (patent CTIT/UFMG NRI research group/UFMG). The results show the feasibility of developing compact proton therapy equipment that works like pre-accelerator or post-accelerator to cyclotrons, satisfying the interval energy of 15 MeV to 64 MeV. Methods of reducing costs of manufacture, installation and operation of this equipment will facilitate the dissemination of the proton treatment in Brazil and consequently advances in fighting cancer. (author)

  6. Experience with the functional assessment of cancer therapy-lung (FACT-L) in ECOG 4593, a phase II hyperfractionated accelerated radiation therapy (HART) trial

    PURPOSE: To gain experience in measuring quality of life (QOL) using the FACT-L in patients (pt) with non small cell lung cancer (NSCLC) treated with an altered fractionation regimen, HART, in a Phase II, multiinstitutional ECOG trial. MATERIALS AND METHODS: Version 2 of FACT-L, with 43 questions in 6 subscale categories (8 physical well-being, 8 social/family well-being, 3 relationship with doctor, 6 emotional well-being, 8 functional well-being, 10 lung cancer symptoms), available in English, Spanish and French, was administered by data managers and filled out by pts, independent of physician presence or input. The HART trial enrolled 30 pts, and FACT-L was administered at baseline (tp 1), treatment completion (tp 2) and 4 weeks following therapy (tp 3). (35(43)) FACT-L items were designed to yield a total QOL score with higher values reflective of better QOL; in addition, a FACT-L trial outcome index (TOI) was computed (TOI = physical score + functional score + lung cancer related score), and is considered the most relevant clinical QOL measure. RESULTS: The FACT-L completion rates were: tp 1 - (30(30)) (100%), tp 2 - (29(30)) (97%) and tp 3 - (24(30)) (80%); the mean scores at various time points are summarized in the table below and indicate that FACT-L is responsive to changes over time. The differences in subscales and total scores can be used as a measure of change in QOL resulting from treatment; statistically significant change was noted from baseline to tp 2 for physical, emotional and functional well-being; and from baseline to tp 3 for emotional well-being. The change in TOI score was also evaluated as a function of response and toxicity grade, and no clear association emerged. When assessed as a function of survival (at the time of this analysis, (5(30)) pt were alive, with median survival of 56 weeks), the degradation in QOL was most severe for pt who died early; the mean change in TOI from baseline to tp 3 for pt dying in the first 25 weeks, 25

  7. Cancer therapy with particle accelerators

    Amaldi, Ugo

    1999-01-01

    This review paper is devoted to conventional radiotherapy and to hadron therapy. In this therapeutical modality, proposed by R. R. Wilson in 1946, the physical selectivity of proton and light ion beams is used to irradiate tissues very close to organs at risk, which cannot be irradiated (the brain and the spinal cord for instance). Also fast neutrons are employed, but they are not suitable for a truly conformal irradiation. Carbon ions have the added advantage, with respect to protons, of the high density of ionization at the end of the range in matter. This property is very valuable for the control of tumours which are radioresistant to both X-rays and protons. After clarifying the general principles, a review is presented of the world hadron therapy centres which are running or are in the design and construction stage. (33 refs).

  8. Winter therapy for the accelerators

    Corinne Pralavorio

    2016-01-01

    Hundreds of people are hard at work during the year-end technical stop as all the accelerators are undergoing maintenance, renovation and upgrade operations in parallel.   The new beam absorber on its way to Point 2 before being lowered into the LHC tunnel for installation. The accelerator teams didn’t waste any time before starting their annual winter rejuvenation programme over the winter. At the end of November, as the LHC ion run was beginning, work got under way on the PS Booster, where operation had already stopped. On 14 December, once the whole complex had been shut down, the technical teams turned their attention to the other injectors and the LHC. The year-end technical stop (YETS) provides an opportunity to carry out maintenance work on equipment and repair any damage as well as to upgrade the machines for the upcoming runs. Numerous work projects are carried out simultaneously, so good coordination is crucial. Marzia Bernardini's team in the Enginee...

  9. Pre-irradiation carboplatin and etoposide and accelerated hyperfractionated radiation therapy in patients with high-grade astrocytomas: a phase II study

    Purpose: To investigate feasibility, activity and toxicity of pre-irradiation chemotherapy (CHT) in patients with newly diagnosed high-grade astrocytoma. Material and Methods: Thirty-five patients with glioblastoma multiform (GBM) and ten patients with anaplastic astrocytoma (AA) entered into this study. Three weeks after surgery patients started their CHT consisting of two cycles of carboplatin (CBDCA) (C) 400 mg/m2, day 1 and etoposide (VP 16) (E) 120 mg/m2, days 1-3, given in a 3-week interval. One week after the second cycle of CE, accelerated hyperfractionated radiation therapy (ACC HFX RT) was introduced with tumor dose of 60 Gy in 40 fractions in 20 treatment days in 4 weeks, 1.5 Gy b.i.d. fractionation.Results: Responses to two cycles of CE could be evaluated in 29 (67%) of 43 patients who received it. Fourteen patients were found impossible to determine radiographic response due to an absence of post-operative contrast enhancement because they were all grossly totally resected. There were 7, 24% (95% confidence intervals - CI, 9-40%), PR (2 AA and 5 GBM), 19 SD, and 3 PD. After RT, of those 29 patients, there were 3 CR and 11 PR (overall objective response rate was 48% (95% CI, 30-67%)), 12 SD, and 3 PD. Median survival time (MST) for all 45 patients is 14 months (95% CI, 11-20 months, while median time to progression (MTP) for all patients is 12 months (95% CI, 8-16 months). Toxicities of this combined modality approach were mild to moderate, with the incidences of CHT-induced grade 3 leukopenia, being 5% (95% CI, 0-11%), and grade 3 thrombocytopenia being 7% (95% CI, 0-15%). Of RT-induced toxicity, grade 1 external otitis was observed in 26% (95% CI, 13-39%), while nausea, vomiting and somnolence were each observed in 5% (95% CI, 0-11%) patients.Conclusion: Pre-irradiation CE and ACC HFX RT was a feasible treatment regimen with mild to moderate toxicity, but failed to improve results over what usually would be obtained with 'standard' approach in this

  10. Decline of Cosmetic Outcomes Following Accelerated Partial Breast Irradiation Using Intensity Modulated Radiation Therapy: Results of a Single-Institution Prospective Clinical Trial

    Liss, Adam L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Ben-David, Merav A. [Department of Radiation Oncology, The Sheba Medical Center, Ramat Gan (Israel); Jagsi, Reshma; Hayman, James A. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Griffith, Kent A. [Biostatistics Unit, University of Michigan, Ann Arbor, Michigan (United States); Moran, Jean M.; Marsh, Robin B. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Pierce, Lori J., E-mail: ljpierce@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2014-05-01

    Purpose: To report the final cosmetic results from a single-arm prospective clinical trial evaluating accelerated partial breast irradiation (APBI) using intensity modulated radiation therapy (IMRT) with active-breathing control (ABC). Methods and Materials: Women older than 40 with breast cancer stages 0-I who received breast-conserving surgery were enrolled in an institutional review board-approved prospective study evaluating APBI using IMRT administered with deep inspiration breath-hold. Patients received 38.5 Gy in 3.85-Gy fractions given twice daily over 5 consecutive days. The planning target volume was defined as the lumpectomy cavity with a 1.5-cm margin. Cosmesis was scored on a 4-category scale by the treating physician. Toxicity was scored according to National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE version 3.0). We report the cosmetic and toxicity results at a median follow-up of 5 years. Results: A total of 34 patients were enrolled. Two patients were excluded because of fair baseline cosmesis. The trial was terminated early because fair/poor cosmesis developed in 7 of 32 women at a median follow-up of 2.5 years. At a median follow-up of 5 years, further decline in the cosmetic outcome was observed in 5 women. Cosmesis at the time of last assessment was 43.3% excellent, 30% good, 20% fair, and 6.7% poor. Fibrosis according to CTCAE at last assessment was 3.3% grade 2 toxicity and 0% grade 3 toxicity. There was no correlation of CTCAE grade 2 or greater fibrosis with cosmesis. The 5-year rate of local control was 97% for all 34 patients initially enrolled. Conclusions: In this prospective trial with 5-year median follow-up, we observed an excellent rate of tumor control using IMRT-planned APBI. Cosmetic outcomes, however, continued to decline, with 26.7% of women having a fair to poor cosmetic result. These results underscore the need for continued cosmetic assessment for patients treated with APBI by technique.

  11. Decline of Cosmetic Outcomes Following Accelerated Partial Breast Irradiation Using Intensity Modulated Radiation Therapy: Results of a Single-Institution Prospective Clinical Trial

    Purpose: To report the final cosmetic results from a single-arm prospective clinical trial evaluating accelerated partial breast irradiation (APBI) using intensity modulated radiation therapy (IMRT) with active-breathing control (ABC). Methods and Materials: Women older than 40 with breast cancer stages 0-I who received breast-conserving surgery were enrolled in an institutional review board-approved prospective study evaluating APBI using IMRT administered with deep inspiration breath-hold. Patients received 38.5 Gy in 3.85-Gy fractions given twice daily over 5 consecutive days. The planning target volume was defined as the lumpectomy cavity with a 1.5-cm margin. Cosmesis was scored on a 4-category scale by the treating physician. Toxicity was scored according to National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE version 3.0). We report the cosmetic and toxicity results at a median follow-up of 5 years. Results: A total of 34 patients were enrolled. Two patients were excluded because of fair baseline cosmesis. The trial was terminated early because fair/poor cosmesis developed in 7 of 32 women at a median follow-up of 2.5 years. At a median follow-up of 5 years, further decline in the cosmetic outcome was observed in 5 women. Cosmesis at the time of last assessment was 43.3% excellent, 30% good, 20% fair, and 6.7% poor. Fibrosis according to CTCAE at last assessment was 3.3% grade 2 toxicity and 0% grade 3 toxicity. There was no correlation of CTCAE grade 2 or greater fibrosis with cosmesis. The 5-year rate of local control was 97% for all 34 patients initially enrolled. Conclusions: In this prospective trial with 5-year median follow-up, we observed an excellent rate of tumor control using IMRT-planned APBI. Cosmetic outcomes, however, continued to decline, with 26.7% of women having a fair to poor cosmetic result. These results underscore the need for continued cosmetic assessment for patients treated with APBI by technique

  12. Stereotactic body radiation therapy (SBRT) for lung malignancies: preliminary toxicity results using a flattening filter-free linear accelerator operating at 2400 monitor units per minute

    Flattening filter-free (FFF) linear accelerators (linacs) are capable of delivering dose rates more than 4-times higher than conventional linacs during SBRT treatments, causing some to speculate whether the higher dose rate leads to increased toxicity owing to radiobiological dose rate effects. Despite wide clinical use of this emerging technology, clinical toxicity data for FFF SBRT are lacking. In this retrospective study, we report the acute and late toxicities observed in our lung radiosurgery experience using a FFF linac operating at 2400 MU/min. We reviewed all flattening filter-free (FFF) lung SBRT cases treated at our institution from August 2010 through July 2012. Patients were eligible for inclusion if they had at least one clinical assessment at least 30 days following SBRT. Pulmonary, cardiac, dermatologic, neurologic, and gastrointestinal treatment related toxicities were scored according to CTCAE version 4.0. Toxicity observed within 90 days of SBRT was categorized as acute, whereas toxicity observed more than 90 days from SBRT was categorized as late. Factors thought to influence risk of toxicity were examined to assess relationship to grade > =2 toxicity. Sixty-four patients with >30 day follow up were eligible for inclusion. All patients were treated using 10 MV unflattened photons beams with intensity modulated radiation therapy (IMRT) inverse planning. Median SBRT dose was 48 Gy in 4 fractions (range: 30–60 Gy in 3–5 fractions). Six patients (9%) experienced > = grade 2 acute pulmonary toxicity; no non-pulmonary acute toxicities were observed. In a subset of 49 patients with greater than 90 day follow up (median 11.5 months), 11 pulmonary and three nerve related grade > =2 late toxicities were recorded. Pulmonary toxicities comprised six grade 2, three grade 3, and one each grade 4 and 5 events. Nerve related events were rare and included two cases of grade 2 chest wall pain and one grade 3 brachial plexopathy which spontaneously resolved. No

  13. ICT accelerators for radiation applications

    Several ICT accelerators were designed and constructed during the past two decades and are now in use in some factories and institutes in various parts of China. The specifications, design considerations, construction specialities and information about the applications of these accelerators are given in the present paper. (author)

  14. Feasibility of using laser ion accelerators in proton therapy

    Bulanov, S V

    2002-01-01

    The feasibility of using the laser plasma as a source of the high-energy ions for the proton radiation therapy is discussed. The proposal is based on the recent inventions of the effective ions acceleration in the experiments and through numerical modeling of the powerful laser radiation interaction with the gaseous and solid state targets. The principal peculiarity of the dependence of the protons energy losses in the tissues (the Bragg peak of losses) facilities the solution of one of the most important problems of the radiation therapy, which consists in realizing the tumor irradiation by sufficiently high and homogeneous dose with simultaneous minimization of the irradiation level, relative to the healthy and neighbouring tissues and organs

  15. Radiation safety research at Indus accelerator complex

    A brief description of the radiation safety research being carried out at the electron synchrotron radiation sources, Indus-1 (450 MeV) and Indus-2 (2.5 GeV) is presented. As these sources being operated at high energy, the radiation environment is primarily due to the interaction of these electrons with accelerating structure, when beam loss takes place, and subsequent development of electromagnetic cascade. Radiation in the cascade mainly consists of the Bremsstrahlung component which initiates photo-neutron production. Characteristics of these radiations are that the energy can be as high up to the energy of the accelerated electron. This gives rise to problems in detection and personnel dosimetry due to dose buildup effects. The angular dependency and pulsed nature of these radiations complicate the issue of detection. Besides, accidental loss of beam in the vacuum envelope of the accelerator, in addition to normal loss calls for appropriate evaluation of these contributions for personnel radiation safety. Attempts made to understand these problems and the research and development work carried out at Indus Accelerator Complex in order to address them will be discussed. (author)

  16. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    Cossairt, J.D.

    1993-11-01

    This report discusses the following topics: Composition of Accelerator Radiation Fields; Shielding of Electrons and Photons at Accelerators; Shielding of Hadrons at Accelerators; Low Energy Prompt Radiation Phenomena; Induced Radioactivity at Accelerators; Topics in Radiation Protection Instrumentation at Accelerators; and Accelerator Radiation Protection Program Elements.

  17. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    This report discusses the following topics: Composition of Accelerator Radiation Fields; Shielding of Electrons and Photons at Accelerators; Shielding of Hadrons at Accelerators; Low Energy Prompt Radiation Phenomena; Induced Radioactivity at Accelerators; Topics in Radiation Protection Instrumentation at Accelerators; and Accelerator Radiation Protection Program Elements

  18. Terahertz radiation from laser accelerated electron bunches

    Coherent terahertz and millimeter wave radiation from laser accelerated electron bunches has been measured. The bunches were produced by tightly focusing (spot diameter ∼ 6 (micro)m) a high peak power (up to 10 TW), ultra-short ((ge)50 fs) laser pulse from a high repetition rate (10 Hz) laser system (0.8 (micro)m), onto a high density (>1019 cm-3) pulsed gas jet of length ∼ 1.5 mm. As the electrons exit the plasma, coherent transition radiation is generated at the plasma-vacuum boundary for wavelengths long compared to the bunch length. Radiation in the 0.3-19 THz range and at 94 GHz has been measured and found to depend quadratically on the bunch charge. The measured radiated energy for two different collection angles is in good agreement with theory. Modeling indicates that optimization of this table-top source could provide more than 100 (micro)J/pulse. Together with intrinsic synchronization to the laser pulse, this will enable numerous applications requiring intense terahertz radiation. This radiation can also be used as a powerful tool for measuring the properties of laser accelerated bunches at the exit of the plasma accelerator. Preliminary spectral measurements indicates that bunches as short as 30-50 fs have been produced in these laser driven accelerators

  19. External Radiation Therapy

    Full Text Available ... D.: There are different forms of radiation for prostate cancer. They really boil down to two different types. There's what we call external beam treatment, which is given from an x-ray ... the prostate. [beeping] Narrator: The more common form of radiation ...

  20. Radiation safety consideration during intraoperative radiation therapy

    Using in-house-designed phantoms, the authors evaluated radiation exposure rates in the vicinity of a newly acquired intraoperative radiation therapy (IORT) system: Axxent Electronic Brachytherapy System. The authors also investigated the perimeter radiation levels during three different clinical intraoperative treatments (breast, floor of the mouth and bilateral neck cancer patients). Radiation surveys during treatment delivery indicated that IORT using the surface applicator and IORT using balloons inserted into patient body give rise to exposure rates of 200 mR h-1, 30 cm from a treated area. To reduce the exposure levels, movable lead shields should be used as they reduce the exposure rates by >95 %. The authors' measurements suggest that intraoperative treatment using the 50-kVp X-ray source can be administered in any regular operating room without the need for radiation shielding modification as long as the operators utilise lead aprons and/or stand behind lead shields. (authors)

  1. Illusory Flow in Radiation from Accelerating Charge

    Biro, Tamas S; Schram, Zsolt

    2014-01-01

    In this paper we analyze the classical electromagnetic radiation of an accelerating point charge moving on a straight line trajectory. Depending on the duration of accelerations, rapidity distributions of photons emerge, resembling the ones obtained in the framework of hydrodynamical models by Landau or Bjorken. Detectable differences between our approach and spectra obtained from hydrodynamical models occur at high transverse momenta and are due to interference.

  2. Radiative processes of uniformly accelerated entangled atoms

    Menezes, G

    2015-01-01

    We study radiative processes of uniformly accelerated entangled atoms, interacting with an electromagnetic field prepared in the Minkowski vacuum state. We discuss the structure of the rate of variation of the atomic energy for two atoms travelling in different hyperbolic world lines. We identify the contributions of vacuum fluctuations and radiation reaction to the generation of entanglement as well as to the decay of entangled states. Our results resemble the situation in which two inertial atoms are coupled individually to two spatially separated cavities at different temperatures. In addition, for equal accelerations we obtain that the maximally entangled antisymmetric Bell state is a decoherence-free state.

  3. External Radiation Therapy

    Full Text Available ... the cancer is not completely contained in the prostate or when the patient is older the treatment ... D.: There are different forms of radiation for prostate cancer. They really boil down to two different ...

  4. Rectal injuries following radiation therapy

    Rectal injuries following radiation therapy were reviewed. Primary diseases in which radiation injuries appeared were described, and local injuries in the neibouring organs such as the small intestine, the bladder, the uterus, and the vagina were also referred to. Classification, frequency, fistulation, radiation necrosis, x-ray findings and occurrence time of rectal and sigmoid colonic injuries were reported. As occurrence factors of radiation injuries, total dose, measurement of dose, stage of primary disease, and history of laparatomy were mentioned. Countermeasures for reducing rectal injuries and treatment methods of local injuries were also described. (Serizawa, K.)

  5. Radiation Therapy of Pituitary Tumors

    Radiation treatment results were analyzed in a retrospective analysis of 47 patients with pituitary adenoma treated with radiation alone or combined with surgery from 1974 through 1987 at the Department of Therapeutic Radiology of Kyung Hee University. The 5-year overall survival rates for all patients was 80.4%. Radiation therapy was effective for improving visual symptoms and headache, but could not normalize amenorrhea and galactorrhoea. There was no difference of survival rate between radiation alone and combination with surgery. Prognostic factors such as age, sex, disease type, visual field, headache and surgical treatment were statistically no significant in survival rates of these patients

  6. Curative radiation therapy in prostate cancer

    Radiotherapy has experienced an extremely rapid development in recent years. Important improvements such as the introduction of multileaf collimators and computed tomography (CT)-based treatment planning software have enabled three dimensional conformal external beam radiation therapy (3DCRT). The development of treatment planning systems and technology for brachytherapy has been very rapid as well. Development of accelerators with integrated on-board imaging equipment and technology, for example image-guided radiation therapy (IGRT) has further improved the precision with reduced margins to adjacent normal tissues. This has, in turn, led to the possibility to administer even higher doses to the prostate than previously. Although radiotherapy and radical prostatectomy have been used for the last decades as curative treatment modalities, still there are no randomized trials published comparing these two options. Outcome data show that the two treatment modalities are highly comparable when used for low- and intermediate-risk prostate cancer

  7. Late Toxicity and Patient Self-Assessment of Breast Appearance/Satisfaction on RTOG 0319: A Phase 2 Trial of 3-Dimensional Conformal Radiation Therapy-Accelerated Partial Breast Irradiation Following Lumpectomy for Stages I and II Breast Cancer

    Purpose: Late toxicities and cosmetic analyses of patients treated with accelerated partial breast irradiation (APBI) on RTOG 0319 are presented. Methods and Materials: Patients with stages I to II breast cancer ≤3 cm, negative margins, and ≤3 positive nodes were eligible. Patients received three-dimensional conformal external beam radiation therapy (3D-CRT; 38.5 Gy in 10 fractions twice daily over 5 days). Toxicity and cosmesis were assessed by the patient (P), the radiation oncologist (RO), and the surgical oncologist (SO) at 3, 6, and 12 months from the completion of treatment and then annually. National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, was used to grade toxicity. Results: Fifty-two patients were evaluable. Median follow-up was 5.3 years (range, 1.7-6.4 years). Eighty-two percent of patients rated their cosmesis as good/excellent at 1 year, with rates of 64% at 3 years. At 3 years, 31 patients were satisfied with the treatment, 5 were not satisfied but would choose 3D-CRT again, and none would choose standard radiation therapy. The worst adverse event (AE) per patient reported as definitely, probably, or possibly related to radiation therapy was 36.5% grade 1, 50% grade 2, and 5.8% grade 3 events. Grade 3 AEs were all skin or musculoskeletal-related. Treatment-related factors were evaluated to potentially establish an association with observed toxicity. Surgical bed volume, target volume, the number of beams used, and the use of bolus were not associated with late cosmesis. Conclusions: Most patients enrolled in RTOG 0319 were satisfied with their treatment, and all would choose to have the 3D-CRT APBI again

  8. Late Toxicity and Patient Self-Assessment of Breast Appearance/Satisfaction on RTOG 0319: A Phase 2 Trial of 3-Dimensional Conformal Radiation Therapy-Accelerated Partial Breast Irradiation Following Lumpectomy for Stages I and II Breast Cancer

    Chafe, Susan, E-mail: susan.chafe@albertahealthservices.ca [Department of Radiation Oncology, Cross Cancer Institute-University of Alberta, Edmonton, Alberta (Canada); Moughan, Jennifer [Department of Radiation Oncology, RTOG Statistical Center, Philadelphia, Pennsylvania (United States); McCormick, Beryl [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wong, John [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland (United States); Pass, Helen [Womens' Breast Center, Stamford Hospital, Stamford, Connecticut (United States); Rabinovitch, Rachel [Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado (United States); Arthur, Douglas W. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Petersen, Ivy [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); White, Julia [Department of Radiation Oncology, Ohio State University, Columbus, Ohio (United States); Vicini, Frank A. [Michigan Healthcare Professionals/21st Century Oncology, Farmington Hills, Michigan (United States)

    2013-08-01

    Purpose: Late toxicities and cosmetic analyses of patients treated with accelerated partial breast irradiation (APBI) on RTOG 0319 are presented. Methods and Materials: Patients with stages I to II breast cancer ≤3 cm, negative margins, and ≤3 positive nodes were eligible. Patients received three-dimensional conformal external beam radiation therapy (3D-CRT; 38.5 Gy in 10 fractions twice daily over 5 days). Toxicity and cosmesis were assessed by the patient (P), the radiation oncologist (RO), and the surgical oncologist (SO) at 3, 6, and 12 months from the completion of treatment and then annually. National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, was used to grade toxicity. Results: Fifty-two patients were evaluable. Median follow-up was 5.3 years (range, 1.7-6.4 years). Eighty-two percent of patients rated their cosmesis as good/excellent at 1 year, with rates of 64% at 3 years. At 3 years, 31 patients were satisfied with the treatment, 5 were not satisfied but would choose 3D-CRT again, and none would choose standard radiation therapy. The worst adverse event (AE) per patient reported as definitely, probably, or possibly related to radiation therapy was 36.5% grade 1, 50% grade 2, and 5.8% grade 3 events. Grade 3 AEs were all skin or musculoskeletal-related. Treatment-related factors were evaluated to potentially establish an association with observed toxicity. Surgical bed volume, target volume, the number of beams used, and the use of bolus were not associated with late cosmesis. Conclusions: Most patients enrolled in RTOG 0319 were satisfied with their treatment, and all would choose to have the 3D-CRT APBI again.

  9. External Radiation Therapy

    Full Text Available Narrator: When the cancer is not completely contained in the prostate or when the patient is older the treatment that is frequently used ... There are different forms of radiation for prostate cancer. They really boil down to two different types. ...

  10. Radiation Therapy for Cancer

    ... Cancers by Body Location Childhood Cancers Adolescent & Young Adult Cancers Metastatic Cancer Recurrent Cancer Research NCI’s Role in ... the affected area). Damage to the bowels, causing diarrhea and ... a second cancer caused by radiation exposure. Second cancers that develop ...

  11. Intensity-modulated radiation therapy.

    Goffman, Thomas E; Glatstein, Eli

    2002-07-01

    Intensity-modulated radiation therapy (IMRT) is an increasingly popular technical means of tightly focusing the radiation dose around a cancer. As with stereotactic radiotherapy, IMRT uses multiple fields and angles to converge on the target. The potential for total dose escalation and for escalation of daily fraction size to the gross cancer is exciting. The excitement, however, has greatly overshadowed a range of radiobiological and clinical concerns. PMID:12071811

  12. Radiation safety aspects at Indus accelerator complex

    Indus Accelerator Complex at Raja Ramanna Center for Advanced Technology houses two synchrotron radiation sources Indus-1 and Indus-2 that are being operated round-the-clock to cater to the needs of the research community. Indus-1 is a 450 MeV electron storage ring and Indus-2 is presently being operated with electrons stored at 2 GeV. Bremsstrahlung radiation and photo-neutrons form the major radiation environment in Indus Accelerator Complex. They are produced due to loss of electron-beam occurring at different stages of operation of various accelerators located in the complex. The synchrotron radiation (SR) also contributes as a potential hazard. In order to ensure safety of synchrotron radiation users and operation and maintenance staff working in the complex from this radiation, an elaborate radiation safety system is in place. The system comprises a Personnel Protection System (PPS) and a Radiation Monitoring System (RMS). The PPS includes zoning, radiation shielding, door interlocks, a search and scram system and machine operation trip-interlocks. The RMS consists of area radiation monitors and beam loss monitors, whose data is available online in the Indus control room. Historical data of radiation levels is also available for data analysis. Synchrotron radiation beamlines at Indus-2 are handled in a special manner owing to the possibility of exposure to synchrotron radiation. Shielding hutches with SR monitors are installed at each beamline of Indus-2. Health Physics Unit also carries out regular radiological surveillance for photons and neutrons during various modes of operation and data is logged shift wise. The operation staff is appropriately trained and qualified as per the recommendations of Atomic Energy Regulatory Board (AERB). Safety training is also imparted to the beamline users. Safe operation procedures and operation checklists are being followed strictly. A radiation instrument calibration facility is also being set-up at RRCAT. The radiation

  13. Electron accelerator applications for radiation processing

    Full text: Department of Nuclear Sciences and Applications (NS) - contributes to the worldwide nuclear sciences and technology development. Through NS, jointly with institutes and laboratories worldwide, the IAEA supports R and D on critical problems facing developing countries. Work targets food, health, water, environment and high tech areas where nuclear and radiation technologies can make a difference. The results and recommendations from the programme elaborated at NAPC lead to organization and execution of the following meetings on the most important issues regarding radiation technology applications, mostly based on accelerator technology: - Technical Meeting (TM) on 'Emerging Applications of Radiation Processing', April, 2003, Vienna, Austria (TECDOC-1386) - Consultants Meeting (CT) on 'Advances in Radiation Processing of Polymers', September 2003, Notre Dame, Indiana, U.S.A. (TECDOC-1420) - Consultants Meeting (CT) on 'Status of Industrial Scale Radiation Treatment of Wastewater', October 2003, Daejon, Republic of Korea (TECDOC-1407) - Consultants Meeting (CT) on 'Radiation Processing of Polysaccharides', November 2003, Takasaki, Japan (TECDOC-1422) - Consultants Meeting (CT) on 'Emerging Applications of Radiation in Nanotechnology', March 2004, Bologna, Italy (TECDOC-1438) - Consultants Meeting (CT) on 'Radiation Processing of Gaseous and Liquid Effluents', September 2004, Sofia, Bulgaria. The total number of accelerators installed all over the world exceeds 13,000, among them the number of units applied for radiation processing being close to 1,200. Direct, transformer accelerators, single resonant cavity accelerators and microwave source powered linear accelerators have been found to be the most suitable for radiation processing. The industrial accelerators' development is still in progress, not only due to new areas of application but also because of demands of lower cost and more compact size machines. Some new countries elaborated their own

  14. Khan's the physics of radiation therapy

    Khan, Faiz M

    2014-01-01

    Expand your understanding of the physics and practical clinical applications of advanced radiation therapy technologies with Khan's The Physics of Radiation Therapy, 5th edition, the book that set the standard in the field. This classic full-color text helps the entire radiation therapy team-radiation oncologists, medical physicists, dosimetrists, and radiation therapists-develop a thorough understanding of 3D conformal radiotherapy (3D-CRT), stereotactic radiosurgery (SRS), high dose-rate remote afterloaders (HDR), intensity modulated radiation therapy (IMRT), image-guided radiation therapy (

  15. Radiation therapy for endometrial carcinoma

    Although pelvic irradiation has traditionally been employed as an adjunct to surgery, the role of radiation therapy as a definitive therapeutic modality continues to be controversial. One-hundred and twenty-one patients were treated for endometrial carcinoma between 1978 and 1985 at the Medical College of Virginia Hospital. These patients were divided into three groups with respect to their treatment. Group 1 consisted of 16 patients who had preoperative radiation therapy, group 2 consisted of 77 patients who had postoperative radiation therapy, and group 3 consisted of 28 patients who had radiation therapy alone. Ninety-three percent of the patients in groups 1 and 2 and 68% of patients in group 3 had stages I and II disease. In group 3, 32% of the patients had stages III and IV disease. Two-thirds of the patients in groups 1 and 2 had moderately differentiated tumor. One-third of patients in group 3 had poorly differentiated tumor. Sixty percent of the study's population in group 2 had deep myometrial invasion. The treatment doses utilized and local failures will be presented. All of the patients have been followed for a minimum period of 2 years. The observed actuarial 5-year survival was 85%, 80%, and 53%, respectively, for groups 1, 2, and 3. The overall survival of the entire patient population was 77%. There was 1 fatality secondary to small bowel complication in group 2 and another serious complication of rectovaginal fistula in group 1 requiring colostomy. Other side effects were skin reaction, diarrhea, and cystitis, which were treated symptomatically. Analysis of the authors' institution experience with adenocarcinoma of the endometrium and its management with radiation therapy is presented. Survival is correlated with stage, grade, and depth of myometrial invasion

  16. Phase II Study of Accelerated High-Dose Radiotherapy With Concurrent Chemotherapy for Patients With Limited Small-Cell Lung Cancer: Radiation Therapy Oncology Group Protocol 0239

    Purpose: To investigate whether high-dose thoracic radiation given twice daily during cisplatin-etoposide chemotherapy for limited small-cell lung cancer (LSCLC) improves survival, acute esophagitis, and local control rates relative to findings from Intergroup trial 0096 (47%, 27%, and 64%). Patients and Methods: Patients were accrued over a 3-year period from 22 US and Canadian institutions. Patients with LSCLC and good performance status were given thoracic radiation to 61.2 Gy over 5 weeks (daily 1.8-Gy fractions on days 1-22, then twice-daily 1.8-Gy fractions on days 23-33). Cisplatin (60 mg/m2 IV) was given on day 1 and etoposide (120 mg/m2 IV) on days 1-3 and days 22-24, followed by 2 cycles of cisplatin plus etoposide alone. Patients who achieved complete response were offered prophylactic cranial irradiation. Endpoints included overall and progression-free survival; severe esophagitis (Common Toxicity Criteria v 2.0) and treatment-related fatalities; response (Response Evaluation Criteria in Solid Tumors); and local control. Results: Seventy-two patients were accrued from June 2003 through May 2006; 71 were evaluable (median age 63 years; 52% female; 58% Zubrod 0). Median survival time was 19 months; at 2 years, the overall survival rate was 36.6% (95% confidence interval [CI] 25.6%-47.7%), and progression-free survival 19.7% (95% CI 11.4%-29.6%). Thirteen patients (18%) experienced severe acute esophagitis, and 2 (3%) died of treatment-related causes; 41% achieved complete response, 39% partial response, 10% stable disease, and 6% progressive disease. The local control rate was 73%. Forty-three patients (61%) received prophylactic cranial irradiation. Conclusions: The overall survival rate did not reach the projected goal; however, rates of esophagitis were lower, and local control higher, than projected. This treatment strategy is now one of three arms of a prospective trial of chemoradiation for LSCLC (Radiation Therapy Oncology Group 0538/Cancer and

  17. Phase II Study of Accelerated High-Dose Radiotherapy With Concurrent Chemotherapy for Patients With Limited Small-Cell Lung Cancer: Radiation Therapy Oncology Group Protocol 0239

    Komaki, Ritsuko, E-mail: rkomaki@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Paulus, Rebecca [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Ettinger, David S. [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland (United States); Videtic, Gregory M.M. [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States); Bradley, Jeffrey D. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States); Glisson, Bonnie S. [Department of Thoracic/Head and Neck Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Langer, Corey J. [Thoracic Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Sause, William T. [Radiation Center, LDS Hospital, Salt Lake City, Utah (United States); Curran, Walter J. [Department of Radiation Oncology, Jefferson Medical College, Philadelphia, Pennsylvania (United States); Choy, Hak [Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas (United States)

    2012-07-15

    Purpose: To investigate whether high-dose thoracic radiation given twice daily during cisplatin-etoposide chemotherapy for limited small-cell lung cancer (LSCLC) improves survival, acute esophagitis, and local control rates relative to findings from Intergroup trial 0096 (47%, 27%, and 64%). Patients and Methods: Patients were accrued over a 3-year period from 22 US and Canadian institutions. Patients with LSCLC and good performance status were given thoracic radiation to 61.2 Gy over 5 weeks (daily 1.8-Gy fractions on days 1-22, then twice-daily 1.8-Gy fractions on days 23-33). Cisplatin (60 mg/m{sup 2} IV) was given on day 1 and etoposide (120 mg/m{sup 2} IV) on days 1-3 and days 22-24, followed by 2 cycles of cisplatin plus etoposide alone. Patients who achieved complete response were offered prophylactic cranial irradiation. Endpoints included overall and progression-free survival; severe esophagitis (Common Toxicity Criteria v 2.0) and treatment-related fatalities; response (Response Evaluation Criteria in Solid Tumors); and local control. Results: Seventy-two patients were accrued from June 2003 through May 2006; 71 were evaluable (median age 63 years; 52% female; 58% Zubrod 0). Median survival time was 19 months; at 2 years, the overall survival rate was 36.6% (95% confidence interval [CI] 25.6%-47.7%), and progression-free survival 19.7% (95% CI 11.4%-29.6%). Thirteen patients (18%) experienced severe acute esophagitis, and 2 (3%) died of treatment-related causes; 41% achieved complete response, 39% partial response, 10% stable disease, and 6% progressive disease. The local control rate was 73%. Forty-three patients (61%) received prophylactic cranial irradiation. Conclusions: The overall survival rate did not reach the projected goal; however, rates of esophagitis were lower, and local control higher, than projected. This treatment strategy is now one of three arms of a prospective trial of chemoradiation for LSCLC (Radiation Therapy Oncology Group 0538

  18. Radiation therapy for retinoblastoma

    Treatment results were examined about 39 retinoblastoma introduced to the radiotherapy purpose, at National Center for Child Health and Development, during the 37 years from 1975 to 2012. In 29 patients of bilateral, 24 patients were postoperative radiotherapy, 4 patients were for preservation purpose. In 10 unilateral patients, 5 patients were postoperative, 4 patients were for preservation purpose. Delayed adverse events, 11 patients with cataracts requiring surgery, pituitary dysfunction 2 patients who take a hormone replacement, 1 glaucoma, were showed. The recurrence was 6 patients, and inner 1 patient was a trilateral retinoblastoma, and turned into the only death case. The onset of secondary cancer was observed in 4 patients, 1 was Merkel cell carcinoma and 3 patients were rhabdomyosarcoma. All had occurred out of the radiation field. (author)

  19. Anaemia and radiation therapy

    Anaemia is frequent in cancer and may increase tumour hypoxia that stimulates angiogenesis. However, erythropoietin is a hypoxia-inducible stimulator of erythropoiesis which seems to improve quality of life in cancer patients. Two recent phase III randomized studies showed negative results using erythropoietin in head and neck cancer patients and in metastatic breast cancer patients with impaired specific survival. In vitro and in vivo experiments have provided erythropoietin-receptor expression in endothelial cancer cells including malignant tumours of the breast, prostate, cervix, lung, head and neck, ovary, melanoma, stomach, gut, kidney etc. Biologic effect of erythropoietin and its receptor linkage induces proliferation of human breast cancer and angiogenesis and may limit anti-tumour effect of cancer treatment, in part, by tumour vascularization improvement. In addition, the use of exogenous erythropoietin could be able to favour tumour progression by improving tumour oxygenation and nutriment supply. If erythropoietin receptor were functional in human cancer. the assessment of erythropoietin receptor expression on tumour cell may help to select patients benefiting from exogenous erythropoietin. However. the relationship between erythropoietin receptor expression, tumour growth and exogenous erythropoietin. requires more studies. The results of recent clinical trials suggest that using erythropoietin should be avoided in non-anemic patients and discussed in patients receiving curative therapy. (authors)

  20. Radiation Therapy: Preventing and Managing Side Effects

    ... yourself during radiation therapy Radiation therapy can damage healthy body tissues in or near the area being treated, which can cause side effects. Many people worry about this part of their cancer treatment. Before ...

  1. Electromagnetic radiation. Variational methods, waveguides and accelerators

    This is a graduate level textbook on the theory of electromagnetic radiation and its application to waveguides, transmission lines, accelerator physics and synchrotron radiation. It has grown out of lectures and manuscripts by Julian Schwinger prepared during the war at MIT's Radiation Laboratory, updated with material developed by Schwinger at UCLA in the 1970s and 1980s, and by Milton at the University of Oklahoma since 1994. The book includes a great number of straightforward and challenging exercises and problems. It is addressed to students in physics, electrical engineering, and applied mathematics seeking a thorough introduction to electromagnetism with emphasis on radiation theory and its applications. A hardcover edition containing additionally the reprints of more than 15 papers by Schwinger on these topics is available separately. (orig.)

  2. Radiation therapy of esophageal cancer

    Radiation therapy has been used extensively in the management of patients with cancer of the esophagus. It has demonstrated an ability to cure a small minority of patients. Cure is likely to be limited to patients who have lesions less than 5 cm in length and have minimal, if any, involvement of lymph nodes. Esophagectomy is likely to cure a similar, small percentage of patients with the same presentation of minimal disease but has a substantial acute postoperative mortality rate and greater morbidity than irradiation. Combining surgery and either preoperative or postoperative irradiation may cure a small percentage of patients beyond the number cured with either modality alone. Radiation has demonstrated benefit as an adjuvant to surgery following the resection of minimal disease. However, radiation alone has never been compared directly with surgery for the highly select, minimal lesions managed by surgery. Radiation provides good palliation of dysphagia in the majority of patients, and roughly one third may have adequate swallowing for the duration of their illness when ''radical'' doses have been employed. Surgical bypass procedures have greater acute morbidity but appear to provide more reliable, prolonged palliation of dysphagia. Several approaches to improving the efficacy of irradiation are currently under investigation. These approahces include fractionation schedules, radiosensitizers, neutron-beam therapy, and helium-ion therapy

  3. Radiation from Shock-Accelerated Particles

    Nishikawa, Ken-ichi; Choi, E. J.; Min, K. W.; Niemiec, J.; Zhang, B.; Hardee, P.; Mizuno, Y.; Medvedev, M.; Nordlund, A.; Frederiksen, J.; Sol, H.; Pohl, M.; Hartmann, D. H.; Fishman, G. J.

    2012-01-01

    Plasma instabilities excited in collisionless shocks are responsible for particle acceleration, generation of magnetic fields , and associated radiation. We have investigated the particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma. Cold jet electrons are thermalized and slowed while the ambient electrons are swept up to create a partially developed hydrodynamic-like shock structure. The shock structure depends on the composition of the jet and ambient plasma (electron-positron or electron-ions). Strong electromagnetic fields are generated in the reverse , jet shock and provide an emission site. These magnetic fields contribute to the electron's transverse deflection behind the shock. We have calculated, self-consistently, the radiation from electrons accelerated in the turbulent magnetic fields. We found that the synthetic spectra depend on the Lorentz factor of the jet, its thermal temperature and strength of the generated magnetic fields. The detailed properties of the radiation are important for understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jet shocks, and supernova remnants

  4. Injection accelerator for proton therapy system

    We have developed the magnet-free alternating phase focusing (APF) linac for proton cancer therapy facilities. This new linac enhances the reliability and serviceability of such facilities. The newly developed linac uses radio-frequency electric field to accelerate as well as focus a beam of protons (hydrogen nuclei). The electric field is designed with 'sawtooth-shaped phase modulation technology', which can generate high-quality beam. The elimination of magnets has resulted in a simplified linac structure that requires very few adjustments, resulting in improved reliability and serviceability. The system uses a resonant coupler to distribute radio-frequency power, the first such commercial application in the world. The ratio-frequency power supply has been integrated into a single unit, simplifying the structure of the facility. There is no need to adjust the ratio-frequency power phase, for easy servicing. (author)

  5. Megavoltage radiation therapy: Meeting the technological needs

    addressing technological needs for megavoltage radiation treatment, that the radiation treatment machine technology not be considered in isolation from the technologies associated with the other steps of the treatment process. It makes no sense to have highly sophisticated linear accelerators capable of 3-D conformal and intensity modulated radiation therapy (IMRT) if there is not a good imaging capability for accurately defining the extent and location of both tumours and normal tissues. Requirements for a radiation therapy facility have been defined in an IAEA report. This report considered cobalt-60 megavoltage therapy machines but indicated that the IAEA would not consider provisions for linear accelerators. In 1993, the Pan American Health Organization along with the WHO and the IAEA produced a report describing the design requirements for megavoltage x-ray machines for cancer treatment in developing countries. Clearly, even within the last decade, there are still different opinions on the benefits (and risks) of cobalt-60 versus linear accelerators for provision of radiation treatment especially in the context of developing countries. There are a number of considerations when a particular institution in any country makes decisions about the purchase of radiation therapy equipment. Broadly speaking, these include: Societal infrastructure considerations (e.g. is there stable electrical power available to support the treatment and related technologies?); Financial considerations (e.g. are there sufficient financial resources to purchase, operate, maintain and eventually dispose of the treatment technology?); Types and stage of diseases most likely to be treated (e.g. late stage diseases have different planning and treatment requirements compared to early stage and well localized tumours); The number and types of professional staff available to support the treatment technologies (e.g. radiation oncologists, medical physicists, radiation therapists (technologists), and

  6. Oray surgery and radiation therapy

    Carl, W.

    1975-07-01

    Clinical evidence seems to indicate that careful oral surgery after radiation therapy contributes little, if anything at all, to the onset of osteoradionecrosis. In many cases the process of bone dissolution has already well progressed before teeth have to be extracted. The bone changes can be demonstrated radiographically and clinically. The teeth in the immediate area become very mobile and cause severe pain during mastication. Whether this condition could have been prevented by extractions before radiation therapy is difficult to establish. Osteoradionecrosis may be encountered in edentulous jaws. It manifests itself clinically by bone segments which break loose and penetrate through the mucosa leaving a defect which does not heal over. More research and more comparative studies are needed in this area in order to make reasonably accurate predictions.

  7. Radiation Therapy and Hearing Loss

    A review of literature on the development of sensorineural hearing loss after high-dose radiation therapy for head-and-neck tumors and stereotactic radiosurgery or fractionated stereotactic radiotherapy for the treatment of vestibular schwannoma is presented. Because of the small volume of the cochlea a dose-volume analysis is not feasible. Instead, the current literature on the effect of the mean dose received by the cochlea and other treatment- and patient-related factors on outcome are evaluated. Based on the data, a specific threshold dose to cochlea for sensorineural hearing loss cannot be determined; therefore, dose-prescription limits are suggested. A standard for evaluating radiation therapy-associated ototoxicity as well as a detailed approach for scoring toxicity is presented.

  8. [Radiation therapy of pancreatic cancer].

    Huguet, F; Mornex, F; Orthuon, A

    2016-09-01

    Currently, the use of radiation therapy for patients with pancreatic cancer is subject to discussion. In adjuvant setting, the standard treatment is 6 months of chemotherapy with gemcitabine and capecitabine. Chemoradiation (CRT) may improve the survival of patients with incompletely resected tumors (R1). This should be confirmed by a prospective trial. Neoadjuvant CRT is a promising treatment especially for patients with borderline resectable tumors. For patients with locally advanced tumors, there is no a standard. An induction chemotherapy followed by CRT for non-progressive patients reduces the rate of local relapse. Whereas in the first trials of CRT large fields were used, the treated volumes have been reduced to improve tolerance. Tumor movements induced by breathing should be taken in account. Intensity modulated radiation therapy allows a reduction of doses to the organs at risk. Whereas widely used, this technique is not recommended. PMID:27523418

  9. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are described qualitatively and quantitatively. In the same manner the primary radiation fields produced by proton and ion beams are described. Subsequent chapters describe: shielding of electrons and photons at accelerators; shielding of proton and ion accelerators; low energy prompt radiation phenomena; induced radioactivity at accelerators; topics in radiation protection instrumentation at accelerators; and accelerator radiation protection program elements

  10. Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

    Cossairt, J.D.

    1996-10-01

    In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are described qualitatively and quantitatively. In the same manner the primary radiation fields produced by proton and ion beams are described. Subsequent chapters describe: shielding of electrons and photons at accelerators; shielding of proton and ion accelerators; low energy prompt radiation phenomena; induced radioactivity at accelerators; topics in radiation protection instrumentation at accelerators; and accelerator radiation protection program elements.

  11. Radiation therapy for pleural mesothelioma

    There is clear evidence that both pleural and peritoneal malignant mesothelioma are increasing in incidence in the United States. There is a recognized long period of latency from asbestos exposure to the emergence and diagnosis of tumor. Considering the levels of asbestos utilization in the mid-20th century, we must expect that the number of cases will continue to increase until the end of this century. Evaluation of treatment options is thus a critical issue in determining treatment approaches for this disease. Recognized only recently, mesothelioma has no effective treatment, and patients are reported only anecdotally as cured. Pleural mesothelioma is the more common presentation, but even here the reports are from small, uncontrolled series. Only one study is available in which a concomitant comparison of treatment methods was carried out. Randomized clinical studies regarding treatment of pleural mesothelioma have only recently been initiated by the clinical cooperative groups. There is thus a paucity of information on treatment in general and radiation therapy specifically for malignant mesothelioma. This chapter reviews the reported experience using radiation therapy alone and combined with other modalities for the treatment of malignant pleural mesothelioma and considers the potential for improvement of the results of current methods of radiation therapy

  12. New frontier of laser particle acceleration: driving protons to 80 MeV by radiation pressure

    Kim, I Jong; Kim, Chul Min; Kim, Hyung Taek; Lee, Chang-Lyoul; Choi, Il Woo; Singhal, Himanshu; Sung, Jae Hee; Lee, Seong Ku; Lee, Hwang Woon; Nickles, Peter V; Jeong, Tae Moon; Nam, Chang Hee

    2014-01-01

    The radiation pressure acceleration (RPA) of charged particles has been considered a challenging task in laser particle acceleration. Laser-driven proton/ion acceleration has attracted considerable interests due to its underlying physics and potential for applications such as high-energy density physics, ultrafast radiography, and cancer therapy. Among critical issues to overcome the biggest challenge is to produce energetic protons using an efficient acceleration mechanism. The proton acceleration by radiation pressure is considerably more efficient than the conventional target normal sheath acceleration driven by expanding hot electrons. Here we report the generation of 80-MeV proton beams achieved by applying 30-fs circularly polarized laser pulses with an intensity of 6.1 x 1020 W/cm2 to ultrathin targets. The radiation pressure acceleration was confirmed from the obtained optimal target thickness, quadratic energy scaling, polarization dependence, and 3D-PIC simulations. We expect this fast energy scalin...

  13. Development of local radiation therapy

    The major limitations of radiation therapy for cancer are the low effectiveness of low LET and inevitable normal tissue damage. Boron Neutron Capture Therapy (BNCT) is a form of potent radiation therapy using Boron-10 having a high propensityof capturing theraml neutrons from nuclear reactor and reacting with a prompt nuclear reaction. Photodynamic therapy is a similiar treatment of modality to BNCT using tumor-seeking photosenistizer and LASER beam. If Boron-10 and photosensitizers are introduced selectively into tumor cells, it is theoretically possible to destroy the tumor and to spare the surrounding normal tissue. Therefore, BNCT and PDT will be new potent treatment modalities in the next century. In this project, we performed PDT in the patients with bladder cancers, oropharyngeal cancer, and skin cancers. Also we developed I-BPA, new porphyrin compounds, methods for estimation of radiobiological effect of neutron beam, and superficial animal brain tumor model. Furthermore, we prepared preclinical procedures for clinical application of BNCT, such as the macro- and microscopic dosimetry, obtaining thermal neutron flux from device used for fast neutron production in KCCH have been performed

  14. Development of local radiation therapy

    Lee, Seung Hoon; Lim, Sang Moo; Choi, Chang Woon; Chai, Jong Su; Kim, Eun Hee; Kim, Mi Sook; Yoo, Seong Yul; Cho, Chul Koo; Lee, Yong Sik; Lee, Hyun Moo

    1999-04-01

    The major limitations of radiation therapy for cancer are the low effectiveness of low LET and inevitable normal tissue damage. Boron Neutron Capture Therapy (BNCT) is a form of potent radiation therapy using Boron-10 having a high propensityof capturing theraml neutrons from nuclear reactor and reacting with a prompt nuclear reaction. Photodynamic therapy is a similiar treatment of modality to BNCT using tumor-seeking photosenistizer and LASER beam. If Boron-10 and photosensitizers are introduced selectively into tumor cells, it is theoretically possible to destroy the tumor and to spare the surrounding normal tissue. Therefore, BNCT and PDT will be new potent treatment modalities in the next century. In this project, we performed PDT in the patients with bladder cancers, oropharyngeal cancer, and skin cancers. Also we developed I-BPA, new porphyrin compounds, methods for estimation of radiobiological effect of neutron beam, and superficial animal brain tumor model. Furthermore, we prepared preclinical procedures for clinical application of BNCT, such as the macro- and microscopic dosimetry, obtaining thermal neutron flux from device used for fast neutron production in KCCH have been performed.

  15. Late complications of radiation therapy

    There are cases in which, although all traces of acute radiation complications seem to have disappeared, late complications may appear months or years to become apparent. Trauma, infection or chemotherapy may sometimes recall radiation damage and irreversible change. There were two cases of breast cancer that received an estimated skin dose in the 6000 cGy range followed by extirpation of the residual tumor. The one (12 y.o.) developed atrophy of the breast and severe teleangiectasis 18 years later radiotherapy. The other one (42 y.o.) developed severe skin necrosis twenty years later radiotherapy after administration of chemotherapy and received skin graft. A case (52 y.o.) of adenoidcystic carcinoma of the trachea received radiation therapy. The field included the thoracic spinal cord which received 6800 cGy. Two years and 8 months after radiation therapy she developed complete paraplegia and died 5 years later. A truly successful therapeutic outcome requires that the patient be alive, cured and free of significant treatment-related morbidity. As such, it is important to assess quality of life in long-term survivors of cancer treatment. (author)

  16. Practical risk management in radiation therapy

    Technology advances in radiation therapy is very remarkable. In the technological progress of radiation therapy, development of computer control technology has helped. However, there is no significant progress in the ability of human beings who is operating. In many hospitals, by the incorrect parameter setting and wrong operations at radiation treatment planning system, many incidents have been reported recently. In order to safely use invisible radiation beam for treatment, what we should be careful? In state-of-the-art radiation therapy and many technological progress, risk management should be correspond continue. I report practical risk management in radiation therapy about the technical skills, non-technical skills and the quality control. (author)

  17. Accelerated neuroregulation for therapy of opiate dependency

    S. Sunatrio

    2004-03-01

    Full Text Available Acute weaning from chronic opioid abuse during general anesthesia is usually followed by adrenergic outflow effects. This article is to report our experience with accelerated neuroregulation that reverses the physical and psychological dependency. After a comprehensive psychological and medical examination, 361 heroin dependent patients were admitted to ICU to be hospitalized for a full 24 or 36 hours, including a 6 hour pre-procedure medication process (solbutamol, clonidine, diazepam, ranitidine, omeprazole, vitamin C, octreotide, and ondansetron. Anesthesia was induced with midazolam and propofol iv and maintained with propofol infusion. Naltrexon, clonidine, octreotide, and diazepam were then administered. Anesthesia was maintained for 3 ½ - 5 hours depending on severity of withdrawal symptoms precipitated by naltrexone. Analgetics and sedatives were given as needed afterwards. Upon discharge on the following day, patient was prescribed a regimen of oral naltrexone for 10-12 months. All 361 patients were successfully detoxified without any adverse anesthetic events. The side effects encountered were fatigue, insomnia, drowsy, shivering, abdominal pain, nausea, diarrhoea, myalgia, goose bumps and uncomfortable feeling. In most of the patients these symptoms disappeared without any treatment. Symptomatic treatments were needed in 32.7% of patients. In all 166 patients who completed their naltrexone maintenance treatment, craving disappeared in the 10th month. The main problem was the low patient compliance to oral naltrexone, so that only 45.9% of the patients completed their therapy. Conclusion: Accelerated neuroregulation which includes naltrexone maintenance treatment (10-12 months was highly effective to detoxify and to abolish craving in the heroin dependent patients. (Med J Indones 2004; 13: 53-8Keywords: detoxification, craving management

  18. Radiation therapy of suprasellar germinomas

    From 1974 to 1984, nine patients with suprasellar germinoma were treated with megavoltage radiation therapy. The entire craniospinal axis was irradiated in all patients, with median doses of 45 Gy, 44.4 Gy, and 24 Gy delivered to the tumor volume, whole brain, and spinal cord, respectively. There have been no tumor recurrences, with median 56-month follow-up among seven survivors. Two patients have died (12, 14 months) without evidence of tumor, both of uncontrolled endocrine dysfunction. The dose usually recommended for treatment of intracranial germinoma is 50-55 Gy. The data suggest that 45 Gy may be sufficient

  19. Radiation therapy in bronchogenic carcinoma

    Response of intrathoracic symptoms to thoracic irradiation was evaluated in 330 patients. Superior vena caval syndrome and hemoptysis showed the best response, with rates of 86% and 83%, respectively, compared to 73% for pain in the shoulder and arm and 60% for dyspnea and chest pain. Atelectasis showed re-expansion in only 23% of cases, but this figure increased to 57% for patients with oat-cell carcinoma. Vocal cord paralysis improved in only 6% of cases. Radiation therapy has a definite positive role in providing symptomatic relief for patients with carcinoma of the lung

  20. Insufficiency fracture after radiation therapy

    Insufficiency fracture occurs when normal or physiological stress applied to weakened bone with demineralization and decreased elastic resistance. Recently, many studies reported the development of IF after radiation therapy (RT) in gynecological cancer, prostate cancer, anal cancer and rectal cancer. The RT-induced insufficiency fracture is a common complication during the follow-up using modern imaging studies. The clinical suspicion and knowledge the characteristic imaging patterns of insufficiency fracture is essential to differentiate it from metastatic bone lesions, because it sometimes cause severe pain, and it may be confused with bone metastasis.

  1. Stereotactic body radiation therapy (SBRT) for lung malignancies: preliminary toxicity results using a flattening filter-free linear accelerator operating at 2400 monitor units per minute

    Prendergast, Brendan M; Dobelbower, Michael C; Bonner, James A.; Popple, Richard A.; Baden, Craig J; Minnich, Douglas J.; Cerfolio, Robert J.; Spencer, Sharon A; Fiveash, John B.

    2013-01-01

    Background Flattening filter-free (FFF) linear accelerators (linacs) are capable of delivering dose rates more than 4-times higher than conventional linacs during SBRT treatments, causing some to speculate whether the higher dose rate leads to increased toxicity owing to radiobiological dose rate effects. Despite wide clinical use of this emerging technology, clinical toxicity data for FFF SBRT are lacking. In this retrospective study, we report the acute and late toxicities observed in our l...

  2. Accelerated radiation therapy for locally advanced squamous cell carcinomas of the oral cavity and oropharynx selected according to tumor cell kinetics--a phase II multicenter study

    Purpose: A Phase II multicenter trial testing an accelerated regimen of radiotherapy in locally advanced and inoperable cancers of the head and neck, in patients selected on the basis of 5-bromo-2-deoxyuridine/DNA flow cytometry-derived tumor potential doubling time (Tpot). Methods and Materials: From September 1992 to September 1993, 23 patients consecutively diagnosed to have locally advanced, inoperable carcinomas of the oral cavity and the oropharynx, with Tpot of ≤5 days, received an accelerated radiotherapy regimen (AF) based on a modification of the concomitant boost technique: 2 Gy/fraction once a day, delivered 5 days a week up to 26 Gy, followed by 2 Gy/fraction twice a day, with a 6-h interval, one of the two fractions being delivered as a concomitant boost to reduced fields, up to 66 Gy total dose (off-cord reduction at 46 Gy), shortening the overall treatment time to 4.5 weeks. A contemporary control group of 46 patients with Tpot of >5 days or unknown was treated with conventional fractionation (CF): 2 Gy/fraction once a day, 5 days a week, up to 66 Gy in 6.5 weeks, with fields shrinkage after 46 Gy. Results: All patients completed the accelerated regimen according to protocol and in the prescribed overall treatment time. Immediate tolerance was fairly good: 65% of the patients in the AF group experienced Grade 3 mucositis vs. 45% in the CF group (p = n.s.). Symptoms related to mucosal reactions seemed to persist longer in AF than in CF patients. The crude proportion of mild (Grades 1 and 2) late effects on skin (p < 0.01) and salivary glands (p < 0.05) was higher in AF than in CF patients, although these reactions did not exceed the limits of tolerance. Three patients in the AF and 1 in the CF arm experienced a late Grade 4 bone complication. Actuarial estimates of severe (Grades 3 and 4) late complications showed a 2-year hazard of 33.3% in the AF arm and 49.7% in CF (p = NS). The actuarial 2-year local control rate of the AF patients was 49

  3. Intraoperative radiation therapy. State of the art and outlook

    Intraoperative radiation therapy (IORT)- a medical procedure that uses an electron beam produced by an accelerator to irradiate a cancerous area during surgery, while the patient is still on the operating table- has aroused growing interest in recent years. The use of IORT has been furthered by the development of mobile accelerators, a result due in part to collaboration between ENEA, which provided know-how on accelerators, and Italian industrial concerns. After outlining the evolution of the technologies used in IORT, the article describes the state of the art and compares the systems now on the market, reports the results of clinical applications and delineates possible further developments

  4. Risk analysis of external radiation therapy

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  5. Twenty-year results of treatment of patients with stage i-IIA Hodgkin's lymphoma using radiation therapy with accelerated dose fractionation

    The findings of investigation of 20-year survival of 234 patients with stage IA-IIA Hodgkin's lymphoma (HL) are analyzed. In case of a favorable prognosis according to EORTC criteria total relapse-free survival was 90 and 76% respectively at 10-year and 79 and 73% at 20 year terms of observation. The use of chemoradiation therapy at unfavorable prognosis eliminated the difference in the survival of the patients from different prognostic groups.

  6. The use of recombination chambers at radiation therapy facilities

    Zielczynski, Mieczyslaw [Institute of Atomic Energy, 05-400 Swierk (Poland); Golnik, Natalia, E-mail: golnik@mchtr.pw.edu.p [Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland); Gryzinski, Michal A. [Institute of Atomic Energy, 05-400 Swierk (Poland); Tulik, Piotr [Institute of Atomic Energy, 05-400 Swierk (Poland); Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland)

    2010-12-15

    The paper presents an overview of the applications of recombination chambers for dosimetric measurements at radiotherapy facilities. The chambers were used at electron, proton and heavy ion accelerators, in the beam and in the vicinity of the accelerators at very different dose rates. The examples of measurements discussed in the paper include: the determination of the absorbed dose and radiation quality parameters of a 170 MeV proton beam and BNCT (boron neutron capture therapy) beam, neutron dose measurements at a phantom surface outside the beam of a 15 MV electron medical accelerator, determination of ambient dose equivalent, H* (10) outside the irradiated phantom in the proton therapy treatment room at JINR (Dubna, Russia), and at working places outside the shielding of the heavy ion therapy facility at GSI (Darmstadt, Germany).

  7. The use of recombination chambers at radiation therapy facilities

    The paper presents an overview of the applications of recombination chambers for dosimetric measurements at radiotherapy facilities. The chambers were used at electron, proton and heavy ion accelerators, in the beam and in the vicinity of the accelerators at very different dose rates. The examples of measurements discussed in the paper include: the determination of the absorbed dose and radiation quality parameters of a 170 MeV proton beam and BNCT (boron neutron capture therapy) beam, neutron dose measurements at a phantom surface outside the beam of a 15 MV electron medical accelerator, determination of ambient dose equivalent, H* (10) outside the irradiated phantom in the proton therapy treatment room at JINR (Dubna, Russia), and at working places outside the shielding of the heavy ion therapy facility at GSI (Darmstadt, Germany).

  8. Application of Novel Accelerator Research for Particle Therapy

    Bjerke, Henrik Hemmestad

    2014-01-01

    This thesis seeks to review the latest trends in hadron therapy devices, and evaluate the potential of novel, researched accelerator concepts for future application. Although the clinical benefits of hadron therapy over photon therapy is unproven or disputed for many cancer types, there are several cases where hadron therapy presents a superior option. Many governments and medical institutions are planning or already executing development of new hadron treatment facilities. However, the highe...

  9. Prospective study of accelerated postoperative radiation therapy in patients with squamous-cell carcinoma of the head and neck; Radiotherapie externe acceleree postoperatoire des carcinomes epidermoides localement evolues de la sphere ORL: etude prospective de phase 2

    Zouhair, A.; Coucke, P.A.; Azria, D.; Moeckli, R.; Mirimanoff, R.O.; Ozsahin, M. [Centre Hospitalier Universitaire Vaudois CHUV, Service de Radio-Oncologie, Lausanne (Switzerland); Azria, D. [Centre Regional de Lutte Contre le Cancer Val-d' Aurelle-Paul-Lamarque, Dept. d' Oncologie- Radiotherapie, 34 - Montpellier (France); Pache, P. [Centre Hospitalier Universitaire Vaudois CHUV, Service d' ORL, Lausanne (Switzerland); Stupp, R. [Centre hospitalier Universitaire Vaudois CHUV, Centre Pluridisciplinaire d' Oncologie Medicale, Lausanne (Switzerland)

    2003-08-01

    Purpose. - To assess the feasibility and efficacy of accelerated postoperative radiation therapy (RT) in patients with squamous-cell carcinoma of the head and neck (SCCHN). Patients and methods. - Between December 1997 and July 2001, 68 patients (male to female ratio: 52/16; median age: 60-years (range: 43-81)) with pT1-pT4 and/or pN0-pN3 SCCHN (24 oropharynx, 19 oral cavity, 13 hypopharynx, 5 larynx, 3 unknown primary, 2 maxillary sinus, and 2 salivary gland) were included in this prospective study. Postoperative RT was indicated because extra-capsular infiltration (ECT) was observed in 20 (29%), positive surgical margins (PSM) in 20 (29%) or both in 23 patients (34%). Treatment consisted of external beam R 66 Gy in 5 weeks and 3 days. Median follow-up was 15 months. Results. -According to CTC 2.0, acute morbidity was acceptable: grade 3 mucositis was observed in 15 (22%) patients, grade 3 dysphagia in 19 (28%) patients, grade 3 skin erythema in 21 (31%) patients with a median weight loss of 3.1 kg (range: 0-16). No grade 4 toxicity wa observed. Median time to relapse was 13 months; we observed only three (4%) local and four (6%) regional relapses, whereas eight (12%) patients developed distant metastases without any evidence of locoregional recurrence. The 2 years overall-, disease-free survival, an actuarial locoregional control rates were 85, 73 and 83% respectively. Conclusion.- The reduction of the overall treatment time using postoperative accelerated RT with weekly concomitant boost (six fraction per week) is feasible with local control rates comparable to that of published data. Acute RT related morbidity is acceptable. (author)

  10. DART-bid: dose-differentiated accelerated radiation therapy, 1.8 Gy twice daily. High local control in early stage (I/II) non-small-cell lung cancer

    While surgery is considered standard of care for early stage (I/II), non-small-cell lung cancer (NSCLC), radiotherapy is a widely accepted alternative for medically unfit patients or those who refuse surgery. International guidelines recommend several treatment options, comprising stereotactic body radiation therapy (SBRT) for small tumors, conventional radiotherapy ≥ 60 Gy for larger sized especially centrally located lesions or continuous hyperfractionated accelerated RT (CHART). This study presents clinical outcome and toxicity for patients treated with a dose-differentiated accelerated schedule using 1.8 Gy bid (DART-bid). Between April 2002 and December 2010, 54 patients (median age 71 years, median Karnofsky performance score 70 %) were treated for early stage NSCLC. Total doses were applied according to tumor diameter: 73.8 Gy for 6 cm. The median follow-up was 28.5 months (range 2-108 months); actuarial local control (LC) at 2 and 3 years was 88 %, while regional control was 100 %. There were 10 patients (19 %) who died of the tumor, and 18 patients (33 %) died due to cardiovascular or pulmonary causes. A total of 11 patients (20 %) died intercurrently without evidence of progression or treatment-related toxicity at the last follow-up, while 15 patients (28 %) are alive. Acute esophagitis ≤ grade 2 occurred in 7 cases, 2 patients developed grade 2 chronic pulmonary fibrosis. DART-bid yields high LC without significant toxicity. For centrally located and/or large (> 5 cm) early stage tumors, where SBRT is not feasible, this method might serve as radiotherapeutic alternative to present treatment recommendations, with the need of confirmation in larger cohorts. (orig.)

  11. Cancer Treatment with Gene Therapy and Radiation Therapy

    Kaliberov, Sergey A.; Buchsbaum, Donald J.

    2012-01-01

    Radiation therapy methods have evolved remarkably in recent years which have resulted in more effective local tumor control with negligible toxicity of surrounding normal tissues. However, local recurrence and distant metastasis often occur following radiation therapy mostly due to the development of radioresistance through the deregulation of the cell cycle, apoptosis, and inhibition of DNA damage repair mechanisms. Over the last decade, extensive progress in radiotherapy and gene therapy co...

  12. Melioidosis: reactivation during radiation therapy

    Melioidosis is caused by Pseudomonas pseudomallei, a gram-negative, motile bacillus which is a naturally occurring soil saprophyte. The organism is endemic in Southeast Asia, the Philippines, Australia, and parts of Central and South America. Most human disease occurs from infection acquired in these countries. Infection with P pseudomallei may produce no apparent clinical disease. Acute pneumonitis or septicemia may result from inhalation of the organism, and inoculation into sites of trauma may cause localized skin abscesses, or the disease may remain latent and be reactivated months or years later by trauma, burns, or pneumococcal pneumonia, diabetic ketoacidosis, influenza, or bronchogenic carcinoma. The last is probably the commonest form of melioidosis seen in the United States. We present the first case of reactivation of melioidosis after radiation therapy for carcinoma of the lung, again emphasizing the need to consider melioidosis in a septic patient with a history of travel, especially to Southeast Asia

  13. Melioidosis: reactivation during radiation therapy

    Jegasothy, B.V.; Goslen, J.B.; Salvatore, M.A.

    1980-05-01

    Melioidosis is caused by Pseudomonas pseudomallei, a gram-negative, motile bacillus which is a naturally occurring soil saprophyte. The organism is endemic in Southeast Asia, the Philippines, Australia, and parts of Central and South America. Most human disease occurs from infection acquired in these countries. Infection with P pseudomallei may produce no apparent clinical disease. Acute pneumonitis or septicemia may result from inhalation of the organism, and inoculation into sites of trauma may cause localized skin abscesses, or the disease may remain latent and be reactivated months or years later by trauma, burns, or pneumococcal pneumonia, diabetic ketoacidosis, influenza, or bronchogenic carcinoma. The last is probably the commonest form of melioidosis seen in the United States. We present the first case of reactivation of melioidosis after radiation therapy for carcinoma of the lung, again emphasizing the need to consider melioidosis in a septic patient with a history of travel, especially to Southeast Asia.

  14. Status Of The Dielectric Wall Accelerator For Proton Therapy

    The Dielectric Wall Accelerator (DWA) offers the potential to produce a high gradient linear accelerator for proton therapy and other applications. The current status of the DWA for proton therapy will be reviewed. Recent progress in SiC photoconductive switch development will be presented. There are serious beam transport challenges in the DWA arising from short pulse excitation of the wall. Solutions to these transport difficulties will be discussed.

  15. A phase I/II study piloting accelerated partial breast irradiation using CT-guided intensity modulated radiation therapy in the prone position

    Background and purpose: External beam accelerated partial breast irradiation (EB-aPBI) is noninvasive with broader potential applicability than aPBI using brachytherapy. However, it has inherent challenges in daily reproducibility. Image-guide radiotherapy (IGRT) can improve daily reproducibility, allowing smaller treatment margins. Our institution proposed IG-IMRT in the prone position to evaluate dose homogeneity, conformality, normal tissue avoidance, and reliable targeting for EB-aPBI. We report preliminary results and toxicity from a phase I/II study evaluating the feasibility of EB-aPBI in the prone position using IG-IMRT. Materials and methods: Twenty post-menopausal women with node-negative breast cancer, excised tumors 99% of the PTV. Dose constraints for the whole breast, lungs and heart were met. Results: The median patient age was 61.5. Mean tumor size was 1.0 cm. 35% of patients had DCIS. Median PTV was 243 cc (108–530) and median breast reference volume was 1698 cc (647–3627). Average daily shifts for IGRT were (0.6, −4.6, 1.7 mm) with standard deviations of (6.3, 6.5, 6.4 mm). Acute toxicity was G1 erythema in 80%, and G2 erythema, G2 fatigue, and G2 breast pain each occurred in 1 patient. With a median follow-up of 18.9 months (12–35), 40% of patients have G1 fibrosis and 30% have G1 hyperpigmentation. 95% of patients have good to excellent cosmesis. There have been no recurrences. Conclusions: These data demonstrate that EB-aPBI in the prone position using IG-IMRT is well tolerated, yields good dosimetric conformality, and results in promising early toxicity profiles

  16. Resistance to radiation of a 0.8 μm CMOS VLSI readout of instrumentation for accelerators used in tumor therapy

    This paper shows the results of irradiations with photons and neutrons of a Very Large Scale Integration (VLSI) CMOS AMS 0.8μm chip used in medical physics applications. It has been designed as readout of dosimeters and monitor chambers used on electron/photon and proton/carbon ions for tumor therapy. The chip is located close to the detectors and it is thus used in a radioactive environment. We have performed measurements on 30 MV X-rays, fast and thermal neutrons. The chip behaves well (i.e. the gain variations are below 1%) up to X- ray doses of 75 krad and a total fast neutron number of 4*1012. This allows the use of the chip over several years (>5) without performance modifications. It has to be noticed that in real life the dose rates are much lower than during the tests, allowing a self-repairing of the chip with annealing. No Single Event Effect was observed up to 1010 neutrons. (authors)

  17. Self-shielded electron linear accelerators designed for radiation technologies

    Belugin, V. M.; Rozanov, N. E.; Pirozhenko, V. M.

    2009-09-01

    This paper describes self-shielded high-intensity electron linear accelerators designed for radiation technologies. The specific property of the accelerators is that they do not apply an external magnetic field; acceleration and focusing of electron beams are performed by radio-frequency fields in the accelerating structures. The main characteristics of the accelerators are high current and beam power, but also reliable operation and a long service life. To obtain these characteristics, a number of problems have been solved, including a particular optimization of the accelerator components and the application of a variety of specific means. The paper describes features of the electron beam dynamics, accelerating structure, and radio-frequency power supply. Several compact self-shielded accelerators for radiation sterilization and x-ray cargo inspection have been created. The introduced methods made it possible to obtain a high intensity of the electron beam and good performance of the accelerators.

  18. Radiation therapy of patients with locally advanced forms of upper airway cancer

    These research devoted to the planning and radiation therapy problems and intended for patients with malignant neoplasms of upper airways. Devices ''Rocus AM'', ''Teratron-95'', linear accelerators ''Mevatron-KD-2'' and ''Clinac2100'' was applied toward the patients.

  19. Laser Acceleration of Quasi-Monoenergetic Protons via Radiation Pressure Driven Thin Foil

    We present a theoretical and simulation study of laser acceleration of quasi-monoenergetic protons in a thin foil irradiated by high intensity laser light. The underlying physics of radiation pressure acceleration (RPA) is discussed, including the importance of optimal thickness and circularly polarized light for efficient acceleration of ions to quasi-monoenergetic beams. Preliminary two-dimensional simulation studies show that certain parameter regimes allow for stabilization of the Rayleigh-Taylor instability and possibility of acceleration of monoenergetic ions to an excess of 200 MeV, making them suitable for important applications such as medical cancer therapy and fast ignition.

  20. An international intercomparison of absorbed dose measurements for radiation therapy

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

  1. Booster linear accelerators for proton therapy

    Radiotherapy using proton beams of energies of order 200 MeV is now accepted as a feasible cancer treatment technique whose widespread use has so far been limited by the high costs of proposed facilities. AEA Technology have identified a low-cost solution using a linear accelerator to boost existing hospital cyclotrons. The present project status and the design of the booster linear accelerator are discussed. (Author) 4 tabs., 2 figs., 2 refs

  2. Radiation Therapy for Early Stage Lung Cancer

    Parashar, Bhupesh; Arora, Shruthi; Wernicke, A. Gabriella

    2013-01-01

    Radiation therapy for early stage lung cancer is a promising modality. It has been traditionally used in patients not considered candidates for standard surgical resection. However, its role has been changing rapidly since the introduction of new and advanced technology, especially in tumor tracking, image guidance, and radiation delivery. Stereotactic radiation therapy is one such advancement that has shown excellent local control rates and promising survival in early stage lung cancer. In a...

  3. Applications of radiation monitoring system at Indus Accelerator Complex

    Indus Accelerator Complex (IAC) at RRCAT, Indore houses two high energy electron accelerators Indus-I (450 MeV, 100 mA) and Indus-2 (2.5 GeV, 300 mA). The Radiation Monitoring System (RMS) comprises of area monitoring and personnel monitoring. RMS at IAC provides very useful information about radiation levels, beam loss scenario, unusual incidents etc. In this system the remotely displayed radiation data in control room matches well with the local readings of the respective area radiation monitor. The paper describes various features of Radiation Monitoring System and its applications in radiation exposure control in IAC. (author)

  4. Radiation therapy of CNS lymphoma

    A retrospective analysis of 22 patients with central nervous system (CNS) non-Hodgkin's lymphomas seen from 1978 to 1989 at Hamamatsu University Hospital was carried out. These were corresponding to 16% (22/137) of non-Hodgkin's lymphomas treated by irradiation during the same period. Six patients had primary intracranial involvement, six had secondary one, five had leptomeningeal involvement and five had spinal cord compression. Median survival of these groups 29 months, 7 months, 6 months and 4 months, respectively. On the case primary intracranial involvement, neurological signs and symptoms and performance status (PS) were improved in most patients. Whole brain irradiation with a dose of 45 Gy to 50 Gy followed by systemic chemotherapy was considered as effective treatment modalities. On the other hand, for the secondary intracranial lymphomas, clinical symptoms and PS were excellently improved by radiation therapy; however, these did not reflect survival. The conditions having primary site on gastrointestinal tract and relapse as systemic dissemination were considerable risk factors for the control of CNS involvement. For these patients, prophylactic chemotherapy is necessary. Improvement of PS on patients with leptomeningeal lymphomas was obtained in only 3 of 5 cases. These were treated by irradiation on whole spine or neuroaxis and intrathecal MTX injection. We observed 2 cases dying from cerebrovascular accident and one case from leukoencephalopathy. This showed that such combination therapy should be carefully attempted. Five patients having spinal cord compression suffered from paraplegia and none of them had been improved on their symptoms. Four of 5 patients complained of back pain one to two months before onset of paraplegia without abnormal findings on spine roentgenograms. Therefore, studies with myelography or MRI are considered to be essential to patients with non-Hodgkin's lymphoma who complained of back pain. (author)

  5. Radiation protection activities around the CERN accelerators

    The staff of the Survey Section of Radiation Protection (RP) working around the CERN accelerators were as usual very busy. The LEP2 programme is now fully on its way, with the installation of additional superconducting RF cavities carried out during both the winter and summer shutdowns. The LEP energy per beam was thus increased to 80.5 GeV in summer and to 86 GeV in autumn. ACOL and LEAR ended their operational life on 19 December producing, for the last time, antiprotons for the experiments in the South Hall; all experiments will be dismantled in 1997. This programme will be partly replaced by the future Antiproton Decelerator, which was approved by the Research Board in November. Several experiments also came to their end in the North and West Experimental Areas of the SPS. NA44 (in EHN1) and NA47 (in EHN2) ended this year. All experiments installed in beam lines HI, H3, XI and X3 in the West Area also terminated, as these beam lines will be dismantled in the course of 1997 to make room for test facilities for the LHC. Several modifications in the West and North Experimental Areas have already been undertaken at the end of the year and will be continued in 1997. Some equipment installed in the West Area will be moved to the North Area. In addition to routine work, several measurements of synchrotron radiation were made in LEP for the two new energy levels reached in 1996. A number of dedicated measurements were also undertaken in EHN1 (North Area) at the end of the year, during the lead-ion run which closed the physics period. A detailed assessment of releases of radioactivity from the ISOLDE facility was also made

  6. Neutron radiation area monitoring system for proton therapy facilities

    A neutron radiation area monitoring system has been developed for proton accelerator facilities dedicated to cancer therapy. The system comprises commercial measurement equipment, computer hardware and a suite of software applications that were developed specifically for use in a medical accelerator environment. The system is designed to record and display the neutron dose-equivalent readings from 16 to 24 locations (depending on the size of the proton therapy centre) throughout the facility. Additional software applications provide for convenient data analysis, plotting, radiation protection reporting, and system maintenance and administration tasks. The system performs with a mean time between failures of >6 months. Required data storage capabilities and application execution times are met with inexpensive off-the-shelf computer hardware. (authors)

  7. Radiation Therapy for Gynecologic Cancers

    ... the doctors who oversee the care of each person undergoing radiation treatment. Other members of the treatment team include radiation therapists, radiation oncology nurses, medical physicists, dosimetrists, social workers ...

  8. Technological progress in radiation therapy for brain tumors

    Vernimmen, Frederik Jozef

    2014-01-01

    To achieve a good therapeutic ratio the radiation dose to the tumor should be as high as possible with the lowest possible dose to the surrounding normal tissue. This is especially the case for brain tumors. Technological ad- vancements in diagnostic imaging, dose calculations, and radiation delivery systems, combined with a better un- derstanding of the pathophysiology of brain tumors have led to improvements in the therapeutic results. The widely used technology of delivering 3-D conformal therapy with photon beams (gamma rays) produced by Li-near Accelerators has progressed into the use of Intensity modulated radiation therapy (IMRT). Particle beams have been used for several decades for radiotherapy because of their favorable depth dose characteristics. The introduction of clinically dedicated proton beam therapy facilities has improved the access for cancer patients to this treatment. Proton therapy is of particular interest for pediatric malignancies. These technical improvements are further enhanced by the evolution in tumor physiology imaging which allows for improved delineation of the tumor. This in turn opens the potential to adjust the radiation dose to maximize the radiobiological effects. The advances in both imaging and radiation therapy delivery will be discussed.

  9. Upgrade of accelerator radiation safety system for SPring-8

    The accelerator safety interlock system to protect persons from the radiation damages has been operated in SPring-8. The accelerator safety interlock system is monitoring the condition of safety equipment. If the condition is unsafe, the system stops the electron beam. The accelerator safety interlock system currently running is based on the operation mode control. Since the operation mode based system is quite complex, the system has some problems. Therefore, we are planning to construct new accelerator safety interlock system. We'll report the situation of current accelerator safety interlock system and the conceptual design of new accelerator safety interlock system. (author)

  10. Radiation protection activities around the CERN accelerators

    In 1997 the physics programme of the SPS and LEP was seriously affected by a fire in one of the surface building of the SPS; the incident caused a delay in the LEP start-up, an interruption of several weeks in the SPS fixed-target programme, and the cancellation of the lead ion run for 1997. The consequences for the experiments were, nevertheless, kept to a minimum thanks to the excellent performance of the accelerators. The neutrino experiments even accumulated a record intensity. Experiments at the ISOLDE facility benefited from 315 shifts instead of 200 as originally scheduled, and new experiments started measuring the properties of unstable elements which play a crucial role in the stars. LEP also reached record energy and luminosity in 1997. Measurements of synchrotron radiation in the LEP tunnel were repeated at the new energy value of 92 GeV, to comply with the demands of the INB procedure. Following the end of operation of ACOL and LEAR in December 1996, decommissioning of the Antiproton Accumulator and transformation of the Antiproton Collector into the Antiproton Decelerator started. Experiments in the South Hall were dismantled during the year and the hall will be used partly as a storage area for radioactive components and partly as a test area

  11. Extramammary Paget's disease: role of radiation therapy

    Extra mammary Paget's disease (EMPD) is an uncommon premalignant skin condition that has been traditionally managed with surgery. A report of long-standing Paget's disease with transformation to invasive adenocarcinoma definitively managed with radiation therapy is presented. A review of cases of extramammary Paget's disease treated with radiation therapy is discussed. The use of radiation therapy should be considered in selected cases, as these studies demonstrate acceptable rates of local control when used as an adjunct to surgery, or as a definitive treatment modality. Copyright (2002) Blackwell Science Pty Ltd

  12. Radiation therapy for renal transplant rejection reactions

    Forty-four renal transplant patients were given radiation therapy for severe rejection phenomena. The 29 patients who had only one course of irradiation had a 52.3% successful function rate. Fifteen patients received from two to four courses of irradiation with an ultimate 60% rate of sustained function. Fifty patients who received only steroid and other medical management but no irradiation had a 60% rate of successful renal function. In the irradiation group, no patient whose creatinine level did not respond to radiation therapy maintained a functioning kidney. The data indicate that the overall successful function rate is maintained by radiation therapy in patients who show severe allograft rejection phenomena

  13. Radiation therapy for renal transplant rejection reactions

    Peeples, W.J.; Wombolt, D.G.; El-Mahdi, A.M.; Turalba, C.I.

    1982-01-01

    Forty-four renal transplant patients were given radiation therapy for severe rejection phenomena. The 29 patients who had only one course of irradiation had a 52.3% successful function rate. Fifteen patients received from two to four courses of irradiation with an ultimate 60% rate of sustained function. Fifty patients who received only steroid and other medical management but no irradiation had a 60% rate of successful renal function. In the irradiation group, no patient whose creatinine level did not respond to radiation therapy maintained a functioning kidney. The data indicate that the overall successful function rate is maintained by radiation therapy in patients who show severe allograft rejection phenomena.

  14. Modern radiation therapy for extranodal lymphomas

    Yahalom, Joachim; Illidge, Tim; Specht, Lena;

    2015-01-01

    Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL...... adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other...

  15. Detoxication and antiproteolytic therapy of radiation complications

    Yakhontov, N.E.; Klimov, I.A.; Lavrikova, L.P.; Martynov, A.D.; Provorova, T.P.; Serdyukov, A.S.; Shestakov, A.F. (Gor' kovskij Meditsinskij Inst. (USSR))

    1984-11-01

    49 patients with uterine cervix and ovarian carcinomas were treated with detoxication and antiproteolytic therapy of radiation-induced side-effects. The therapy permits to complete without interruption the remote gamma-therapy course and to reduce patients in-hospital periods by 10+- 1 days. The prescription of hemoder intravenous injection in a dose of 450 ml and contrical intramuscular injection (10000 AtrE) in cases of pronounced manifestations of radiation-induced side-effects (asthenia, leukopenia, enterocolitis) for 3 days should be considered an efficient therapy.

  16. 42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy...

  17. Managing the adverse effects of radiation therapy.

    Berkey, Franklin J

    2010-08-15

    Nearly two thirds of patients with cancer will undergo radiation therapy as part of their treatment plan. Given the increased use of radiation therapy and the growing number of cancer survivors, family physicians will increasingly care for patients experiencing adverse effects of radiation. Selective serotonin reuptake inhibitors have been shown to significantly improve symptoms of depression in patients undergoing chemotherapy, although they have little effect on cancer-related fatigue. Radiation dermatitis is treated with topical steroids and emollient creams. Skin washing with a mild, unscented soap is acceptable. Cardiovascular disease is a well-established adverse effect in patients receiving radiation therapy, although there are no consensus recommendations for cardiovascular screening in this population. Radiation pneumonitis is treated with oral prednisone and pentoxifylline. Radiation esophagitis is treated with dietary modification, proton pump inhibitors, promotility agents, and viscous lidocaine. Radiation-induced emesis is ameliorated with 5-hydroxytryptamine3 receptor antagonists and steroids. Symptomatic treatments for chronic radiation cystitis include anticholinergic agents and phenazopyridine. Sexual dysfunction from radiation therapy includes erectile dysfunction and vaginal stenosis, which are treated with phosphodiesterase type 5 inhibitors and vaginal dilators, respectively. PMID:20704169

  18. Hyperbaric oxygen therapy for radiation myelitis

    Radiation therapy may damage healthy tissues adjacent to tumor. Hyperbaric oxygen therapy (HBO) is useful in treating soft tissue and osteoradionecrosis. In addition, HBO has been recommended to treat radiation-induced myelitis. We used radiation to induce a predictable myelitis in the spinal cords of rats who were randomized into treatment (HBO) and control groups 8 wk after irradiation. Serial neurologic examination showed no benefit or harm as a result of HBO. This small pilot study did not demonstrate any clinically significant benefit of HBO for radiation myelitis in rats

  19. Radiation therapy in elderly patients

    Elderly patients, or those individuals over 65 or 70 depending on the different authors, represent the majority of cancer patients who treated with radiation therapy (RT), however there are very few publications that we provide information needed to evaluate the use of RT in the treatment elders regarding: indication of dose, tissue tolerance, toxicity and association with other therapeutic modalities. In the treatment process must take into account RT radiobiology Clinical applied to each patient and is more relevant in the elderly in which often are comorbid conditions and functional limitations normal tissues increases with age and disease coexisting vascular and connective influencing RT treatment. Chronological age does not correlate with the biological age for tolerance normal tissue, however frequently refers to healthy tissue in the elderly are less tolerant than healthy tissue RT adults young but no data in the literature to support it and perhaps those claims probably based on the presence of comorbid conditions or diseases associated or previous surgeries that influence the risk of tissue damage healthy. Studies conducted by the EORTC not show differences in toxicity acute and late age-related. Elderly patients tolerate RT like younger patients with comparable side effects. In the case of concurrent chronic diseases should take into account a possible modification of the dose and volume irradiated to prevent the risk develop permanent damage or sector body lest un irradiated able to compensate for the loss of function of the irradiated tissue; but we should always note that the dose reduction while reducing the risk of complications also decreases the chance of cure

  20. Radiation protection activities around the CERN accelerators

    As planned, the PS complex started up at the end of March 1998. The machines worked smoothly and the availability of the beams reached from 90% up to 96%. New record intensities were achieved for the 14 GeV/c protons for the SPS fixed-target operation and for the Pb53+ ions. The year 1998 saw the PS complex busy with the transformation of the Antiproton Accumulator (ACOL) into the Antiproton Decelerator (AD). This project is almost finished and the first test beams of protons have already been successfully decelerated in the machine. It is envisaged that the physicists will receive a 100 MeV antiproton beam from October 1999 onwards. Major modifications of the East Hall were required due to the installation of the DIRAC experiment, some test facilities for secondary particles used by LHC experimental groups, and an irradiation area (IRRAD1) for radiation hardness tests of LHC components. The first beams to experimental areas of the East Hall were already sent from July 1998 onwards. The ISOLDE mass separator delivered 275 shifts of radioactive beams of high quality to its user community. The SPS fixed-target programme lasted from 1 April to 30 November. The successful start-up of the accelerators for both the proton and lead-ion periods was followed by stable machine running and by record intensities. The year 1998 marked the end of the operation of the neutrino beam. The dismantling of CHORUS began before the end of the year, to be followed by that of the NOMAD experiment early in 1999

  1. Comparing Postoperative Radiation Therapies for Brain Metastases

    In this clinical trial, patients with one to four brain metastases who have had at least one of the metastatic tumors removed surgically will be randomly assigned to undergo whole-brain radiation therapy or stereotactic radiosurgery.

  2. Nursing care update: Internal radiation therapy

    Internal radiation therapy has been used in treating gynecological cancers for over 100 years. A variety of radioactive sources are currently used alone and in combination with other cancer treatments. Nurses need to be able to provide safe, comprehensive care to patients receiving internal radiation therapy while using precautions to keep the risks of exposure to a minimum. This article discusses current trends and issues related to such treatment for gynecological cancers.20 references

  3. Modern radiation therapy for primary cutaneous lymphomas

    Specht, Lena; Dabaja, Bouthaina; Illidge, Tim;

    2015-01-01

    Primary cutaneous lymphomas are a heterogeneous group of diseases. They often remain localized, and they generally have a more indolent course and a better prognosis than lymphomas in other locations. They are highly radiosensitive, and radiation therapy is an important part of the treatment......, either as the sole treatment or as part of a multimodality approach. Radiation therapy of primary cutaneous lymphomas requires the use of special techniques that form the focus of these guidelines. The International Lymphoma Radiation Oncology Group has developed these guidelines after multinational...... meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the International Lymphoma Radiation Oncology Group steering committee on the use of radiation therapy in primary cutaneous lymphomas in the modern era....

  4. AREAL test facility for advanced accelerator and radiation source concepts

    Tsakanov, V. M.; Amatuni, G. A.; Amirkhanyan, Z. G.; Aslyan, L. V.; Avagyan, V. Sh.; Danielyan, V. A.; Davtyan, H. D.; Dekhtiarov, V. S.; Gevorgyan, K. L.; Ghazaryan, N. G.; Grigoryan, B. A.; Grigoryan, A. H.; Hakobyan, L. S.; Haroutiunian, S. G.; Ivanyan, M. I.; Khachatryan, V. G.; Laziev, E. M.; Manukyan, P. S.; Margaryan, I. N.; Markosyan, T. M.; Martirosyan, N. V.; Mehrabyan, Sh. A.; Mkrtchyan, T. H.; Muradyan, L. Kh.; Nikogosyan, G. H.; Petrosyan, V. H.; Sahakyan, V. V.; Sargsyan, A. A.; Simonyan, A. S.; Toneyan, H. A.; Tsakanian, A. V.; Vardanyan, T. L.; Vardanyan, A. S.; Yeremyan, A. S.; Zakaryan, S. V.; Zanyan, G. S.

    2016-09-01

    Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.

  5. DART-bid: dose-differentiated accelerated radiation therapy, 1.8 Gy twice daily. High local control in early stage (I/II) non-small-cell lung cancer

    Zehentmayr, Franz; Wurstbauer, Karl; Deutschmann, Heinz; Sedlmayer, Felix [Landeskrankenhaus Salzburg, Univ.-Klinik fuer Radiotherapie und Radio-Onkologie, Univ.-Klinikum der Paracelsus Medizinischen Privatuniversitaet, Salzburg (Austria); Paracelsus Medizinische Privatuniversitaet, Institute for Research and Development of Advanced Radiation Technologies (radART), Salzburg (Austria); Fussl, Christoph; Kopp, Peter; Dagn, Karin; Fastner, Gerd [Landeskrankenhaus Salzburg, Univ.-Klinik fuer Radiotherapie und Radio-Onkologie, Univ.-Klinikum der Paracelsus Medizinischen Privatuniversitaet, Salzburg (Austria); Porsch, Peter; Studnicka, Michael [Landeskrankenhaus Salzburg, Univ.-Klinik fuer Pneumologie, Univ.-Klinikum der Paracelsus Medizinischen Privatuniversitaet, Salzburg (Austria)

    2014-09-23

    While surgery is considered standard of care for early stage (I/II), non-small-cell lung cancer (NSCLC), radiotherapy is a widely accepted alternative for medically unfit patients or those who refuse surgery. International guidelines recommend several treatment options, comprising stereotactic body radiation therapy (SBRT) for small tumors, conventional radiotherapy ≥ 60 Gy for larger sized especially centrally located lesions or continuous hyperfractionated accelerated RT (CHART). This study presents clinical outcome and toxicity for patients treated with a dose-differentiated accelerated schedule using 1.8 Gy bid (DART-bid). Between April 2002 and December 2010, 54 patients (median age 71 years, median Karnofsky performance score 70 %) were treated for early stage NSCLC. Total doses were applied according to tumor diameter: 73.8 Gy for < 2.5 cm, 79.2 Gy for 2.5-4.5 cm, 84.6 Gy for 4.5-6 cm, 90 Gy for > 6 cm. The median follow-up was 28.5 months (range 2-108 months); actuarial local control (LC) at 2 and 3 years was 88 %, while regional control was 100 %. There were 10 patients (19 %) who died of the tumor, and 18 patients (33 %) died due to cardiovascular or pulmonary causes. A total of 11 patients (20 %) died intercurrently without evidence of progression or treatment-related toxicity at the last follow-up, while 15 patients (28 %) are alive. Acute esophagitis ≤ grade 2 occurred in 7 cases, 2 patients developed grade 2 chronic pulmonary fibrosis. DART-bid yields high LC without significant toxicity. For centrally located and/or large (> 5 cm) early stage tumors, where SBRT is not feasible, this method might serve as radiotherapeutic alternative to present treatment recommendations, with the need of confirmation in larger cohorts. (orig.) [German] Die Standardbehandlung fuer nichtkleinzellige Bronchialkarzinome (NSCLC) im Stadium I/II ist die Operation, wobei Radiotherapie fuer Patienten, die nicht operabel sind oder die Operation ablehnen, als Alternative

  6. Helium-3 and Helium-4 acceleration by high power laser pulses for hadron therapy

    Bulanov, S. S.; Esarey, E.; Schroeder, C. B.; Leemans, W. P.; Bulanov, S. V.; Margarone, D.; Korn, G.; Haberer, T.

    2015-06-24

    The laser driven acceleration of ions is considered a promising candidate for an ion source for hadron therapy of oncological diseases. Though proton and carbon ion sources are conventionally used for therapy, other light ions can also be utilized. Whereas carbon ions require 400 MeV per nucleon to reach the same penetration depth as 250 MeV protons, helium ions require only 250 MeV per nucleon, which is the lowest energy per nucleon among the light ions. This fact along with the larger biological damage to cancer cells achieved by helium ions, than that by protons, makes this species an interesting candidate for the laser driven ion source. Two mechanisms (Magnetic Vortex Acceleration and hole-boring Radiation Pressure Acceleration) of PW-class laser driven ion acceleration from liquid and gaseous helium targets are studied with the goal of producing 250 MeV per nucleon helium ion beams that meet the hadron therapy requirements. We show that He3 ions, having almost the same penetration depth as He4 with the same energy per nucleon, require less laser power to be accelerated to the required energy for the hadron therapy.

  7. Radiation therapy apparatus having retractable beam stopper

    This invention relates to a radiation therapy apparatus which utilized a linear translation mechanism for positioning a beam stopper. An apparatus is described wherein the beam stopper is pivotally attached to the therapy machine with an associated drive motor in such a way that the beam stopper retracts linearly

  8. Upgrade of accelerator radiation safety system for SPring-8 (2)

    Radiation safety interlock system for the SPring-8 accelerator complex, which protects personnel from radiation hazard induced by electron beams and synchrotron radiation, has been operating over a decade. In the past 10 years, the accelerator was upgraded to extend accelerator/beam-transport areas, and it was implemented new functions. The safety interlock system was also extended. The extended radiation safety interlock system had the complicated safety logic to handle the upgraded accelerator because the safety interlock system was closely related to “Operation MODE” of the accelerator, which is the combination of accelerator/beam-transport areas in operation. This circumstance provoked extensive discussions on the design of new radiation safety interlock system to satisfy the requirements and smooth migration from the old system to the new one. The construction of the new radiation safety interlock system was finalized in September 2010. And the system started the user operation in October 2010. We will report the design of the new radiation safety interlock system and introduction results. (author)

  9. Care of the patient receiving radiation therapy

    External radiation therapy, or teletherapy, is the use of ionizing radiation to destroy cancer cells. Clinical use of ionizing radiation as treatment for cancer began with the discovery of x-rays in 1895, the identification of natural radioactivity (radium) in 1896, and the first reported cure of cancer, a basal cell epithelioma, induced by radiation in 1899. Initially, radiation was administered as a single large dose and produced severe, life-threatening side effects. The basis for the use of ionizing radiation in daily increments for a period of weeks was provided by Regaud in 1922; ten years later, Coutard clinically developed the method of dose fractionation, which remains in use today. Although the use of ionizing radiation as a treatment is over eighty years old, only in recent years have advancements in its clinical application been based on research related to the biologic effect of radiation on human cells. To effectively care for the patient prior to, during, and at the completion of external radiation therapy, the nurse must know the physical and biologic basis of external radiation therapy and its clinical application

  10. Risk of potential radiation accidental situations at TESLA accelerator installation

    The main aim of this paper is to recognize some of the numerous risks of potential exposure and to quantify requirements and probability of failure of radiation protection system due to design event tree. Nature of design and construction of Tesla Accelerator Installation (T.A.I.) make possibility of potential exposure as a result of proven design and modification, trade off, human error as well as defense in depth. In the case of potential exposure human risk is the result of two random events: first, the occurrence of the event that causes the exposure, and the second, the appearance of a harmful effect. The highest doses during potential exposure at T.A.I. can be received at the entrance to primary beam space (V.I.N.C.Y. cyclotron vault) as well as in space with target for fluorine production, high energy experimental channels, proton therapy channel and channel for neutron researches. Expected values of prompt radiation equivalent dose rate in the cyclotron vault is considerably high, in order of 10 Sv/h. Serious problem deals with such large research installation is a number of workers, as visiting research workers of different educational levels and people in Institute who are not professionally connected with ionizing radiation. They could cause willing or unwilling opening of the cyclotron vault doors. Considering some possible scenarios we assumed that during 7000 working hours per year it is reasonably to expect 300 unsafe entries per year. It can be concluded that safety system should be designed so that probability of failure of radiation protection system has to be less than 1.9 10-6. (authors)

  11. High power radiation guiding systems for laser driven accelerators

    This paper reviews the main problems encountered in the design of an optical system for transmitting high fluence radiation in a laser driven accelerator. Particular attention is devoted to the analysis of mirror and waveguide systems. (orig.)

  12. A linear electron accelerator radiation processing facility

    A description is given of the operations of a contract radiation processing facility. The radiation sources are medium energy linacs. Provision is being made for the installation of a cobalt 60 processing facility. A list is given of the radiation processing programmes presently being undertaken. The dosimetry system is described. (U.K.)

  13. Radiation protection systems on the TESLA Accelerator Installation

    In the Institute of Nuclear sciences VINCA, the Accelerator Installation TESLA which is an medium energy ion accelerator facility consisting of an isochronous cyclotron VINCY, a heavy ion source, a D/H ion source, three low energy and five high energy experimental channels is now under construction. Some problems in defining radiation protection and safety programme, particularly problems in construction appropriate shielding barriers at the Accelerator Installation TESLA are discussed in this paper. (author

  14. Wound healing following radiation therapy: a review

    Radiation therapy may interrupt normal wound healing mechanisms. Changes in vasculature, effects on fibroblasts, and varying levels of regulatory growth factors result in the potential for altered wound healing whether radiation is given before or after surgery. Surgical factors, such as incision size, as well as radiation parameters, including dose and fractionation, are important considerations in developing overall treatment plans. Experience suggests that certain practical measures may diminish the risk of morbidity, and investigations are ongoing

  15. Role of radiation therapy in gastric adenocarcinoma

    Lisa Hazard; John O'Connor; Courtney Scaife

    2006-01-01

    Outcomes in patients with gastric cancer in the United States remain disappointing, with a five-year overall survival rate of approximately 23%. Given high rates of local-regional control following surgery, a strong rationale exists for the use of adjuvant radiation therapy.Randomized trials have shown superior local control with adjuvant radiotherapy and improved overall survival with adjuvant chemoradiation. The benefit of adjuvant chemoradiation in patients who have undergone D2 lymph node dissection by an experienced surgeon is not known, and the benefit of adjuvant radiation therapy in addition to adjuvant chemotherapy continues to be defined.In unresectable disease, chemoradiation allows long-term survival in a small number of patients and provides effective palliation. Most trials show a benefit to combined modality therapy compared to chemotherapy or radiation therapy alone.The use of pre-operative, intra-operative, 3D conformal, and intensity modulated radiation therapy in gastric cancer is promising but requires further study.The current article reviews the role of radiation therapy in the treatment of resectable and unresectable gastric carcinoma, focusing on current recommendations in the United States.

  16. Evolution of radiation therapy: technology of today

    The three well established arms of treatment are surgery, radiation therapy and chemotherapy. The management of cancer is multidisciplinary; Radiation Oncologists along with Surgical Oncologists and Medical Oncologists are responsible for cancer therapeutics. They all work in close collaboration with Pathologists and Radiologists for cancer diagnosis and staging and rely on Oncology Nurses, Physiotherapists, Occupational Therapists, Nutritionists and Social Workers for optimal treatment and rehabilitation of cancer patients. Therefore cancer management is a team work for getting the best results. Radiation therapy is one of the most effective methods of treating cancer

  17. Modern Radiation Therapy for Hodgkin Lymphoma

    Specht, Lena; Yahalom, Joachim; Illidge, Tim;

    2014-01-01

    Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced...... Lymphoma Radiation Oncology Group (ILROG) Steering Committee regarding the modern approach to RT in the treatment of HL, outlining a new concept of ISRT in which reduced treatment volumes are planned for the effective control of involved sites of HL. Nodal and extranodal non-Hodgkin lymphomas (NHL) are...... Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided...

  18. Accelerator based neutron source for neutron capture therapy

    Full text: The Budker Institute of Nuclear Physics (Novosibirsk) and the Institute of Physics and Power Engineering (Obninsk) have proposed an accelerator based neutron source for neutron capture and fast neutron therapy for hospital. Innovative approach is based upon vacuum insulation tandem accelerator (VITA) and near threshold 7Li(p,n)7Be neutron generation. Pilot accelerator based neutron source for neutron capture therapy is under construction now at the Budker Institute of Nuclear Physics, Novosibirsk, Russia. In the present report, the pilot facility design is presented and discussed. Design features of facility components are discussed. Results of experiments and simulations are presented. Complete experimental tests are planned by the end of the year 2005

  19. Hawking Radiation of an Arbitrarily Accelerating Kinnersley Black Hole: Spin-Acceleration Coupling Effect

    Shuang-Qing, W; Shuang-Qing, Wu; Mu-Lin, Yan

    2003-01-01

    The Hawking radiation of Weyl neutrinos in an arbitrarily accelerating Kinnersley black hole is investigated by using a method of the generalized tortoise coordinate transformation. Both the location and temperature of the event horizon depend on the time and on the angles. They coincide with previous results, but the thermal radiation spectrum of massless spinor particles displays a kind of spin-acceleration coupling effect.

  20. Hawking Radiation of an Arbitrarily Accelerating Kinnersley Black Hole: Spin-Acceleration Coupling Effect

    吴双清; 闫沐霖

    2003-01-01

    The Hawking radiation of Weyl neutrinos in an arbitrarily accelerating Kinnersley black hole is investigated using a method of the generalized tortoise coordinate transformation.Both the location and temperature of the event horizon depend on the time and on the angles.They are in agreement with the previous results,but thethermal radiation spectrum of massless spinor particles displays a type of spin-acceleration coupling effect.

  1. Protective prostheses during radiation therapy

    Current applications and complications in the use of radiotherapy for the treatment of oral malignancy are reviewed. Prostheses are used for decreasing radiation to vital structures not involved with the lesion but located in the field of radiation. With a program of oral hygiene and proper dental care, protective prostheses can help decrease greatly the morbidity seen with existing radiotherapy regimens

  2. Vitamin A as an adjunct to radiation therapy of cancer

    In a series of animal experiments supplemental Vitamin A (Vit. A) has been found to enhance the effectiveness of irradiation in tumor therapy in several ways: 1. By direct potentiation of radiation effects as manifested by hastening of tumor regression and lessening of metastatic spread. 2. By exerting a protective action against toxicity induced by therapeutic exposure to radiation as expressed by a) moderation of depletion of blood elements (i.e. leucopenia, thrombocytopenia) b) minimizing of damage to mucosal surfaces (i.e. radiation esophagitis) c) reduction of immunosuppression (i.e. increased rate of ''takes'' of transplanted tumors in irradiated animals) d) counteracting of carcinogenic effects (i.e. radiation-induced lymphoma). 3. By accelerating wound healing thereby shortening surgery to irradiation time in post-operative treatment. The above observations derived from their animal experiment which are described in detail suggest that Vit. A may be of value as an antineoplastic and radioprotective agent

  3. Radiation from Accelerated Particles in Shocks and Reconnections

    Nishikawa, K.-I.; Choi, E. J.; Min, K. W.; Niemiec, J.; Fishman, G. J.; Zhang, B.; Hardee, P.; Mizuno, Y.; Medvedev, M.; Nordlund, A.; Frederiksen, J. T.; Sol, H.; Pohl, M.; Hartmann, D. H.

    2012-01-01

    We have investigated particle acceleration and shock structure associated with an unmagnetized relativistic jets propagating into an unmagnetized plasmas. Strong magnetic fields generated in the trailing shock contribute to the electrons transverse deflection and acceleration. We have calculated, self-consistently, the radiation from electrons accelerated in the turbulent magnetic fields. We found that the synthetic spectra depend on the Lorentz factor of the jet, its thermal temperature and strength of the generated magnetic fields. The properties of the radiation may be important for understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets in general, and supernova remnants

  4. Neutron radiation therapy: application of advanced technology to the treatment of cancer

    Maughan, R L; Kota, C; Burmeister, J; Porter, A T; Forman, J D; Blosser, H G; Blosser, E; Blosser, G

    1999-01-01

    The design and construction of a unique superconducting cyclotron for use in fast neutron radiation therapy is described. The clinical results obtained in the treatment of adenocarcinoma of the prostate with this accelerator are presented. Future use of the boron neutron capture reaction as a means of enhancing fast neutron therapy in the treatment of patients with brain tumors (glioblastoma multiforme) is also discussed.

  5. Particle Accelerators and Detectors for medical Diagnostics and Therapy

    Braccini, Saverio

    2016-01-01

    This Habilitationsschrift (Habilitation thesis) is focused on my research activities on medical applications of particle physics and was written in 2013 to obtain the Venia Docendi (Habilitation) in experimental physics at the University of Bern. It is based on selected publications, which represented at that time my major scientific contributions as an experimental physicist to the field of particle accelerators and detectors applied to medical diagnostics and therapy. The thesis is structured in two parts. In Part I, Chapter 1 presents an introduction to accelerators and detectors applied to medicine, with particular focus on cancer hadrontherapy and on the production of radioactive isotopes. In Chapter 2, my publications on medical particle accelerators are introduced and put into their perspective. In particular, high frequency linear accelerators for hadrontherapy are discussed together with the new Bern cyclotron laboratory. Chapter 3 is dedicated to particle detectors with particular emphasis on three ...

  6. PIN photo-diodes as radiation detectors in accelerator applications

    We have been using PIN photo-diodes originally suited for light detection as radiation detectors in several applications: photon monitoring in X-ray machines in industrial and medical applications, X-ray spectroscopy for identification of radioactive materials and XRF, and charged particle spectroscopy. The versatility of these devices as radiation detectors has led us to apply it in several accelerator experiments. This work presents an overview of the results obtained in several experiments: the measurement of charged particles up to 12 MeV in a Tandem accelerator, the measurement of the Bremstralung radiation obtained in an experimental electron accelerator in the range from 70 keV to 470 keV, the direct measurement of the intensity of the electron beam; also the application of PIN photo-diodes in the measurement of the intensity of photons in lineal accelerators used in radiotherapy up to 18 MeV. The front end conditioning electronics associated with the detectors is also described for every application: low noise charge sensitive preamplifiers and current amplifiers are used. The PIN diodes are a good choice for radiation detection in several accelerator applications with the advantage of a good position resolution due to its small size, good sensitivity for different radiation fields and low cost, and can be used to build a wide variety of detection systems around accelerator experiments. (author)

  7. Characterizing THz Coherent Synchrotron Radiation at Femtosecond Linear Accelerator

    LIN Xu-Ling; ZHANG Jian-Bing; LU YU; LUO Feng; LU Shan-Liang; YU Tie-Min; DAI Zhi-Min

    2009-01-01

    The generation and observation of coherent THz synchrotron radiation from femtosecond electron bunches in the Shanghai Institute of Applied Physics femtosecond accelerator device is reported.We describe the experiment setup and present the first result of THz radiation properties such as power and spectrum.

  8. Self-consistent radiative effect on relativistic electromagnetic particle acceleration

    Noguchi, K; Nishimura, K

    2005-01-01

    We study the radiation damping effect on the relativistic acceleration of electron-positron plasmas with two-and-half-dimensional particle-in-cell (PIC) simulation. Particles are accelerated by Poynting flux via the diamagnetic relativistic pulse accelerator (DRPA), and decelerated by the self-consistently solved radiation damping force. With $\\Omega_{ce}/\\omega_{pe}\\geq 10$, the Lorentz factor of the highest energy particles reaches gamma>100, and the acceleration still continues. The emitted radiation is peaked within few degrees from the direction of Poynting flux and strongly linearly polarized, which may be detectable in gamma-ray burst(GRB) observations. We also show that the DRPA is insensitive to the initial supporting currents.

  9. Radiation safety training for accelerator facilities

    In November 1992, a working group was formed within the U.S. Department of Energy's (DOE's) accelerator facilities to develop a generic safety training program to meet the basic requirements for individuals working in accelerator facilities. This training, by necessity, includes sections for inserting facility-specific information. The resulting course materials were issued by DOE as a handbook under its technical standards in 1996. Because experimenters may be at a facility for only a short time and often at odd times during the day, the working group felt that computer-based training would be useful. To that end, Lawrence Livermore National Laboratory (LLNL) and Argonne National Laboratory (ANL) together have developed a computer-based safety training program for accelerator facilities. This interactive course not only enables trainees to receive facility- specific information, but time the training to their schedule and tailor it to their level of expertise

  10. Code of practice for x-ray therapy linear accelerators

    Details are presented on the tests that should be performed during the installation of a megavoltage linear accelerator. Also discussed are the dosimetry studies that should be done as part of the operation of the machine. Information in specific radiation monitoring equipment is provided. (U.S.)

  11. Impact of radiation therapy on sexual life

    The aim of this study was to evaluate the impact of radiation therapy on sexual life. The analysis was based on a Pubmed literature review. The keywords used for this research were 'sexual, radiation, oncology, and cancer'. After a brief reminder on the anatomy and physiology, we explained the main complications of radiation oncology and their impact on sexual life. Preventive measures and therapeutic possibilities were discussed. Radiation therapy entails local, systematic and psychological after-effects. For women, vaginal stenosis and dyspareunia represent the most frequent side effects. For men, radiation therapy leads to erectile disorders for 25 to 75% of the patients. These complications have an echo often mattering on the patient quality of life of and on their sexual life post-treatment reconstruction. The knowledge of the indications and the various techniques of irradiation allow reducing its potential sexual morbidity. The information and the education of patients are essential, although often neglected. In conclusion, radiation therapy impacts in variable degrees on the sexual life of the patients. Currently, there are not enough preventive and therapeutic means. Patient information and the early screening of the sexual complications are at stake in the support of patients in the reconstruction of their sexual life. (authors)

  12. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented

  13. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Aladawi, M. A.; Albarodi, H.; Hammoudeh, A.; Shamma, M.; Sharabi, N.

    2006-01-01

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  14. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Aladawi, M.A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)]. E-mail: Scientific@aec.org.sy; Albarodi, H. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Hammoudeh, A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Shamma, M. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Sharabi, N. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2006-01-15

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  15. Neutron radiation from medical electron accelerators

    A method is described using simple gold foils and relatively inexpensive moderators to measure neutron fluences, both fast nd thermal, which then can be converted to dose equivalent using a few simple formulas. The method is sensitive, easy to calibrate, and should work at most accelerators regardless of energy or room geometry

  16. Cancer and electromagnetic radiation therapy: Quo Vadis?

    Makropoulou, Mersini

    2016-01-01

    In oncology, treating cancer with a beam of photons is a well established therapeutic technique, developed over 100 years, and today over 50% of cancer patients will undergo traditional X-ray radiotherapy. However, ionizing radiation therapy is not the only option, as the high-energy photons delivering their cell-killing radiation energy into cancerous tumor can lead to significant damage to healthy tissues surrounding the tumor, located throughout the beam's path. Therefore, in nowadays, advances in ionizing radiation therapy are competitive to non-ionizing ones, as for example the laser light based therapy, resulting in a synergism that has revolutionized medicine. The use of non-invasive or minimally invasive (e.g. through flexible endoscopes) therapeutic procedures in the management of patients represents a very interesting treatment option. Moreover, as the major breakthrough in cancer management is the individualized patient treatment, new biophotonic techniques, e.g. photo-activated drug carriers, help...

  17. Radiation therapy for intracranial germ cell tumors

    Kato, Shingo; Hayakawa, Kazushige; Tsuchiya, Miwako; Arai, Masahiko; Kazumoto, Tomoko; Niibe, Hideo; Tamura, Masaru

    1988-04-01

    The results of radiation therapy in 31 patients with intracranial germ cell tumors have been analyzed. The five-year survival rates were 70.1 % for germinomas and 38.1 % for teratomas. Three patients with germinoma have since died of spinal seeding. The prophylactic irradiation of the spinal canal has been found effective in protecting spinal seeding, since no relapse of germinoma has been observed in cases that received entire neuraxis iradiation, whereas teratomas and marker (AFP, HCG) positive tumors did not respond favorably to radiation therapy, and the cause of death in these patients has been local failure. Long-term survivors over 3 years after radiation therapy have been determined as having a good quality of life.

  18. An integrated ultrasound-computer dosimetry system for radiation therapy

    A highly interactive on-line computer-based radiation therapy planning system has been developed to allow first-hand participation by the physician for maximum input of clinical judgement in treatment planning. The system utilizes an ultrasound scanning device for acquisition of the patient's contour and anatomical information for simultaneous evaluation by the therapist and processing by the computer. The man-machine interaction and graphic data entry are achieved through a sonic graph pen digitizer mounted on the screen of a multi-colour video monitor. A second graph pen digitizer on a radiograph view box is used for digitization and entry to the computer of other graphic data sources. Radiation treatment parameters are graphically entered directly on the echogram of the patient's cross-sectional anatomy. The radiation dose distribution for a proposed plan is then computed and displayed superimposed in a contrasting colour on the echogram for further scrutiny by the therapist and possible modification. When an acceptable plan is produced, the radiation fields are accurately marked on the patient body in reference to the radiation ports displayed. The system is used for external beam planning with simple, multiple, and irregular fields and intracavitary and interstitial implant dosimetry. Since in this system the radiation delivery is planned based on the cross-sectional anatomy, it is well suited for planning of heavy particle beam therapy which utilizes the stopping characteristics of the accelerated particles in the absorbing medium. (author)

  19. Gene Profiling Technique to Accelerate Stem Cell Therapies for Eye Diseases

    ... to accelerate stem cell therapies for eye diseases Gene profiling technique to accelerate stem cell therapies for ... The method simultaneously measures the expression of multiple genes, allowing scientists to quickly characterize cells according to ...

  20. Radiation Therapy for Pilocytic Astrocytomas of Childhood

    Purpose: Though radiation therapy is generally considered the most effective treatment for unresectable pilocytic astrocytomas in children, there are few data to support this claim. To examine the efficacy of radiation therapy for pediatric pilocytic astrocytomas, we retrospectively reviewed the experience at our institution. Methods and Materials: Thirty-five patients 18 years old or younger with unresectable tumors and without evidence of neurofibromatosis have been treated since 1982. Patients were treated with local radiation fields to a median dose of 54 Gy. Six patients were treated with radiosurgery to a median dose of 15.5 Gy. Five patients were treated with initial chemotherapy and irradiated after progression. Results: All patients were alive after a median follow-up of 5.0 years. However, progression-free survival was 68.7%. None of 11 infratentorial tumors progressed compared with 6 of 20 supratentorial tumors. A trend toward improved progression-free survival was seen with radiosurgery (80%) compared with external beam alone (66%), but this difference did not reach statistical significance. Eight of the 9 patients progressing after therapy did so within the irradiated volume. Conclusions: Although the survival of these children is excellent, almost one third of patients have progressive disease after definitive radiotherapy. Improvements in tumor control are needed in this patient population, and the optimal therapy has not been fully defined. Prospective trials comparing initial chemotherapy to radiation therapy are warranted.

  1. Early cardiac changes related to radiation therapy

    To investigate the incidence and severity of possible radiation-induced cardiac changes, 21 women without heart disease were investigated serially by echocardiography and by measuring systolic time intervals before and up to 6 months after postoperative radiation therapy because of breast cancer. Radiation was associated with a decrease in fractional systolic shortening of the left ventricular (LV) minor-axis diameter, from 0.35 +/- 0.05 to 0.32 +/- 0.06 (p less than 0.005), and in the systolic blood pressure/end-systolic diameter ratio, from 4.4 +/- 1.2 to 3.9 +/- 0.9 mm Hg/mm (p less than 0.005). The mitral E point-septal separation increased, from 2.8 +/- 1.5 to 4.2 +/- 2.5 mm (p less than 0.005). The preejection period/LV ejection time ratio of systolic time intervals increased, but only the decrease within 6 months after therapy was significant (p less than 0.005). All these changes reflect slight transient depression of LV function, which became normalized within 6 months after therapy. Up to 6 months after therapy, a slight pericardial effusion was found in 33% of the patients. Hence, conventional radiation therapy appeared to cause an acute transient and usually symptomless decrease in LV function, and later, slight pericardial effusion in one-third of the patients

  2. Monte Carlo techniques in radiation therapy

    Verhaegen, Frank

    2013-01-01

    Modern cancer treatment relies on Monte Carlo simulations to help radiotherapists and clinical physicists better understand and compute radiation dose from imaging devices as well as exploit four-dimensional imaging data. With Monte Carlo-based treatment planning tools now available from commercial vendors, a complete transition to Monte Carlo-based dose calculation methods in radiotherapy could likely take place in the next decade. Monte Carlo Techniques in Radiation Therapy explores the use of Monte Carlo methods for modeling various features of internal and external radiation sources, including light ion beams. The book-the first of its kind-addresses applications of the Monte Carlo particle transport simulation technique in radiation therapy, mainly focusing on external beam radiotherapy and brachytherapy. It presents the mathematical and technical aspects of the methods in particle transport simulations. The book also discusses the modeling of medical linacs and other irradiation devices; issues specific...

  3. Eosinophilia following radiation therapy Fin childhood

    Radiation related eosinophilia (R.R.E.) has been observed mainly among the patients who received radiation therapy for uterine cancer, which was said to Fbe the sign of good prognosis. Retrospective study of eosinophilia following radiation therapy was performed in 41 pediatric patients with acute lymphoblastic leukemia, brain tumor and so on. Thirty-two per cent of all courses of radiation therapy was associated with R.R.E.. Eosinophil counts increased gradually from two weeks after the start of therapy and reached to maximun on the 33rd day (mean). R.R.E. was seen much more frequently among the patients with brain tumor than those with ALL. And R.R.E. was also related to radiation dose. Patients under 3 years of age showed R.R.E. less frequently comparing to the older age group. Those findings might mean that R.R.E. was strongly related to the host's immunological function. This is the first report about R.R.E. in childhood. (author)

  4. Radiative Effect on Particle Acceleration via Relativistic Electromagnetic Expansion

    Noguchi, K

    2005-01-01

    The radiation damping effect on the diamagnetic relativistic pulse accelerator (DRPA) is studied in two-and-half dimensional Particle-in-Cell (PIC) simulation with magnetized electron-positron plasmas. Self-consistently solved radiation damping force converts particle energy to radiation energy. The DRPA is still robust with radiation, and the Lorentz factor of the most high energy particles reach more than two thousand before they decouple from the electromagnetic pulse. Resulted emitted power from the pulse front is lower in the radiative case than the estimation from the non-radiative case due to the radiation damping. The emitted radiation is strongly linearly polarized and peaked within few degrees from the direction of Poynting flux.

  5. Radiation load of workers on linear accelerators

    Burden of health care personnel working on linear accelerators. New examination and treatment methods enable to reduce the number of health care personnel even in the case of increased numbers of examined patients. However, still open is the question of determining the effective dose delivered to health care personnel. The employment of several methods of evaluation of received dose at one workplace makes it possible to compare the accuracy and reliability of the respective types of measuring devices, as well as to point out the pitfalls of their use.At the St. Elizabeth Cancer Institute we compared the results of measurements of TL dosimeters, and OSL dosimeters at workplaces with linear accelerators. (authors)

  6. Bullous pemphigoid after radiation therapy

    Electron beam therapy applied to a lymph node metastasis from a squamous cell carcinoma was followed by the development of histologically and immunologically typical bullous pemphigoid, the lesions being initially strictly confined to the irradiation area. This observation suggests that the bullous pemphigoid antigen may be altered or unmasked by electron beam radiotherapy, leading subsequently to the production of autoantibodies. The disease in this case effectively responded to the administration of tetracycline and niacinamide, a therapeutic regimen described recently

  7. Malignant peritoneal mesothelioma after radiation therapy

    A 49-year-old woman developed ascites 31 years after radiation therapy for ovarian cancer and was admitted to hospital 1 year later. Diffuse infiltration of both sheets of the peritoneum was found by CT, which on histological investigation turned out to be an advanced malignant peritoneal carcinoma. When there is a history of radiation exposure, malignant peritoneal mesothelioma should be considered as the cause of ascites. (orig.)

  8. Cancer and electromagnetic radiation therapy: Quo Vadis?

    Makropoulou, Mersini

    2016-01-01

    In oncology, treating cancer with a beam of photons is a well established therapeutic technique, developed over 100 years, and today over 50% of cancer patients will undergo traditional X-ray radiotherapy. However, ionizing radiation therapy is not the only option, as the high-energy photons delivering their cell-killing radiation energy into cancerous tumor can lead to significant damage to healthy tissues surrounding the tumor, located throughout the beam's path. Therefore, in nowadays, adv...

  9. Effects of radiation therapy in microvascular anastomoses

    Fried, M.P.

    1985-07-01

    The otolaryngologist, as a head and neck surgeon, commonly cares for patients with upper aerodigestive tract malignancies. Therapy of these neoplasms often requires wide excision. One standard reconstructive procedure utilizes pedicled regional flaps, both dermal and myodermal which have some disadvantages. The shortcomings of these pedicled regional flaps have led to the use of the vascularized free flap in certain cases. The occasional case may lead to catastrophe if microanastomoses fail when combined with radiation. Notwithstanding, many surgical series have reported success when radiation has been given. The present investigation was undertaken to assess the effects of radiation therapy on microvascular anastomoses when radiation is administered pre- or postoperatively or when nonradiated tissue is transferred to an irradiated recipient site. These effects were observed serially in an experimental rat model using a tubed superficial epigastric flap that adequately reflected tissue viability and vascular patency. The histologic changes were then noted over a three month period after completion of both radiation and surgery. This study adds credence to the observation of the lack of deleterious effects of radiation on experimental microvascular anastomotic patency whether the radiation is given before or after surgery or if radiated tissue is approximated to nonradiated vessels.

  10. Effects of radiation therapy in microvascular anastomoses

    The otolaryngologist, as a head and neck surgeon, commonly cares for patients with upper aerodigestive tract malignancies. Therapy of these neoplasms often requires wide excision. One standard reconstructive procedure utilizes pedicled regional flaps, both dermal and myodermal which have some disadvantages. The shortcomings of these pedicled regional flaps have led to the use of the vascularized free flap in certain cases. The occasional case may lead to catastrophe if microanastomoses fail when combined with radiation. Notwithstanding, many surgical series have reported success when radiation has been given. The present investigation was undertaken to assess the effects of radiation therapy on microvascular anastomoses when radiation is administered pre- or postoperatively or when nonradiated tissue is transferred to an irradiated recipient site. These effects were observed serially in an experimental rat model using a tubed superficial epigastric flap that adequately reflected tissue viability and vascular patency. The histologic changes were then noted over a three month period after completion of both radiation and surgery. This study adds credence to the observation of the lack of deleterious effects of radiation on experimental microvascular anastomotic patency whether the radiation is given before or after surgery or if radiated tissue is approximated to nonradiated vessels

  11. Some computer graphical user interfaces in radiation therapy.

    Chow, James C L

    2016-03-28

    In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

  12. Clinical impact of new radiation therapy techniques

    of the 3D planned treatment beams. Further, each RT beam typically delivers a similar intensity of radiation (i.e. dose) to each part of the target. Thus, significant RT doses are typically delivered to all tissues in the 'shadow' of the target, as seen in the 'beams eye view' (BEV). Selection of the beam orientation is therefore critical with 3D planning. Compensators (such as wedges) can be added to the beam to modify the intensity profile of the beam. However, such compensators are relatively simple and provide only uniform and monotonic modulation of the beams intensity (e.g. the entire anterior part of a lateral photon beam given less intensity than the posterior aspect of that same field). With intensity modulated radiation therapy (IMRT), each portion of the beam, or 'beamlet', is modulated to provide a unique intensity. Thus each beam can deliver highly variable doses to each region of the tumour. The purposely non-uniform doses from several beam orientations are combined to deliver the desired dose in a three dimensional space. It is typically not practical for a planner to 'forwardly design' the necessary non-uniform intensity profiles that will yield the desired dose distribution. Rather, the physician defines the desired three dimensional dose distribution and software is used to compute the necessary beam intensity or profiles (i.e. the amount of modulation necessary). Since this process of defining dose, and then beam intensities, is the reverse order from conventional planning, this process as been termed inverse planning. In general, multiple radiation beams (>5-7) are needed to yield an acceptable dose distribution. IMRT appears to be superior to 3D conformal therapy for irregularly shaped tumours, particularly those with concavities. IMRT can be delivered by linear accelerator, or other machines such as the CyberKnife or Tomotherapy unit. With all of these advanced technologies, care must be taken to assure adequate target coverage. Treatment fields

  13. Radiation Therapy of Maxillary Sinus Cancer

    Purpose: Maxillary sinus cancers usually are locally advanced and involve the structures around sinus. It is uncommon for this cancer to spread to the regional lymphnodes. For this reason, local control is of paramount important for cure. A policy of combined treatment is generally accepted as the most effective means of enhancing cure rates. This paper reports our experience of a retrospective study of 31 patients treated with radiation therapy alone and combination therapy of surgery and radiation. Materials and Methods: Between July 1974 and January 1992, 47 patients with maxillary sinus cancers underwent either radiation therapy alone or combination therapy of surgery and radiation. Of these, only 31 patients were eligible for analysis. The distribution of clinical stage by the AJCC system was 26%(8/31) for T2 and 74%(23/31) for T3 and T4. Eight patients had palpable lymphadenopathy at diagnosis. Primary site was treated by Cobalt-60 radiation therapy using through a 45 .deg. wedge-pair technique. Elective neck irradiation was not routinely given. Of these 8 patients, the six who had clinically involved nodes were treated with definite radiation therapy. The other two patients had received radical neck dissection. The twenty-two patients were treated with radiation alone and 9 patients were treated with combination radiation therapy. The RT alone patients with RT dose less than 60 Gy were 9 and those above 60 Gy were 13. Results: The overall 5 year survival rate was 23.8%. The 5 year survival rate by T-stage was 60.5% and 7.9% for T2 and T3, 4 respectively. Statistical significance was found by T-stage (p30.1). The 5 year survival rate for RT alone and combination RT was 22.5% and 27.4%, respectively. The primary local control rate was 65%(20/31). Conclusion: This study did not show significant difference in survival between RT alone and combination RT. There is still much controversy with regard to which treatment is optimum. Improved RT technique and

  14. Particle Accelerators and Detectors for medical Diagnostics and Therapy

    Braccini, Saverio

    2013-01-01

    This Habilitationsschrift (Habilitation thesis) is focused on my research activities on medical applications of particle physics and was written in 2013 to obtain the Venia Docendi (Habilitation) in experimental physics at the University of Bern. It is based on selected publications, which represented at that time my major scientific contributions as an experimental physicist to the field of particle accelerators and detectors applied to medical diagnostics and therapy. The thesis is structur...

  15. Transitioning from 2-D Radiation Therapy to 3-D Conformal Radiation Therapy and Intensity Modulated Radiation Therapy: Training Material

    The technology of radiation oncology has advanced very rapidly in recent years. However, the sophistication of technology available in individual radiation therapy centres varies dramatically throughout the world. Treatment capabilities with planar imaging and limited cross-sectional imaging support have been labelled as two dimensional radiation therapy (2-D RT). With increased use of more advanced cross-sectional imaging, the introduction of more complex dose calculation capabilities for treatment planning and more sophisticated treatment delivery procedures, three dimensional conformal radiation therapy (3-D CRT) can be provided. Further sophistication in treatment planning and treatment delivery capabilities enables intensity modulated radiation therapy (IMRT). Recognizing that huge disparities exist across the world, and in an attempt to aid in advancing institutional capabilities, the IAEA published ‘Transition from 2-D Radiotherapy to 3-D Conformal and Intensity Modulated Radiotherapy’ (IAEA-TECDOC-1588) in May 2008. Divided into two parts — on CRT and on IMRT — the publication provides guidelines on the transition from 2-D RT through 3-D CRT to IMRT. It is recognized that 3-D CRT is the standard of care in most radiation treatment processes and that IMRT technologies are still evolving. The publication provides clear guidelines and highlights the milestones to be achieved when transitioning from 2-D RT to 3-D CRT and IMRT. While IAEA-TECDOC-1588 provides comprehensive guidelines and milestones, the present publication provides training materials to aid professionals in the continuing education required for the implementation of more advanced treatment capabilities, especially 3-D CRT. These materials are based on the results of two consultants meetings organized by the IAEA in 2009 and 2010, primarily focused on providing guidance on what training materials were available or needed to be developed, with a special emphasis on transitioning from 2-D

  16. Electron beams in radiation therapy

    Clinical electron beams in interaction with beam flattening and collimating devices are studied, in order to obtain the means for adequate electron therapy. A treatment planning method for arbitrary field shapes is developed that takes the properties of the collimated electron beams into account. An electron multiple-scattering model is extended to incorporate a model for the loss of electrons with depth, in order to improve electron beam dose planning. A study of ionisation measurements in two different phantom materials yields correction factors for electron beam dosimetry. (Auth.)

  17. Radiation therapy of midline granuloma

    During a 15-year period, 10 patients with well-documented midline granuloma were treated with high-dose, deep local irradiation and followed for extended periods of time. Long-term remissions were achieved in 7 patients, with a mean (+- SEM) survival postirradiation of 7.4 (+-1.4) years in the 6 patients still alive. True midline granuloma, which is a localized, destructive, inflammatory process of the upper airways, can be distinguished from Wegener's granulomatosis and neoplasms of the upper respiratory tract by several clinicopathologic criteria. The cause of midline granuloma is unknown, but it most likely represents an abnormal accelerated hypersensitivity reaction to an unknown antigen(s). Although serious complications of high-dose local irradiation to the upper airways can occur, the risk is warranted because of the high, long-term remission rate in this previously uniformly fatal disease

  18. Delineating organs at risk in radiation therapy

    Cèfaro, Giampiero Ausili; Perez, Carlos A

    2014-01-01

    Defining organs at risk is a crucial task for radiation oncologists when aiming to optimize the benefit of radiation therapy, with delivery of the maximum dose to the tumor volume while sparing healthy tissues. This book will prove an invaluable guide to the delineation of organs at risk of toxicity in patients undergoing radiotherapy. The first and second sections address the anatomy of organs at risk, discuss the pathophysiology of radiation-induced damage, and present dose constraints and methods for target volume delineation. The third section is devoted to the radiological anatomy of orga

  19. Pulmonary function tests after radiation therapy following pneumonectomy

    Radiation is often necessary after pneumonectomy, either immediately or due to local cancer recurrence. High radiation doses represent a challenge due to the limited tolerance of the necessity of preserving and protecting the remaining lung parenchyma. The use of CT scan based-treatment planning allows delivery of high radiation doses. To evaluate the radiation tolerance of the lung after high radiation dose, we compared pulmonary function tests performed before surgery and after radiation therapy. Ten male patients (mean age, 56 years old; age range, 45-73) were irradiated after pneumonectomy for lung cancer. All patients had a CT scan-based treatment planning. The mean radiation dose was 56 Gy (45-66 Gy) delivered with a linear accelerator and multiple complex fields. Two or more sets of pulmonary function tests were available (before surgery and 2 to 6 months after radiation). No patient developed clinical radiation pneumonitis and most of the patients had a minimal para-mediastinal fibrosis at CT scan. Postirradiation pulmonary lung tests were compared to the theoretical values of the estimated defect observed after pneumonectomy. No significant decrease in forced expiratory volume in 1s/inspiratory vital capacity (FEV1/IVC) was observed in ten evaluable patients; the observed values were comparable to those expected after pneumonectomy without irradiation (FEV1/IVC: 61 to 100%), showing that irradiation did not alter pulmonary function. Computerized tomography-based treatment planning and the use of complex beam positioning allowed optimal lung parenchymal preservation. Through this procedure, high doses of radiation can be delivered to the mediastinum and bed tumor. Comparison of pulmonary function tests performed before surgery and after radiation showed no alteration of lung function, even after high doses. Optimal tools required for the evaluation of radiation on lung parenchyma are still to be defined. (authors)

  20. Helium-3 and Helium-4 acceleration by high power laser pulses for hadron therapy

    Bulanov, S S; Schroeder, C B; Leemans, W P; Bulanov, S V; Margarone, D; Korn, G; Haberer, T

    2015-01-01

    The laser driven acceleration of ions is considered a promising candidate for an ion source for hadron therapy of oncological diseases. Though proton and carbon ion sources are conventionally used for therapy, other light ions can also be utilized. Whereas carbon ions require 400 MeV per nucleon to reach the same penetration depth as 250 MeV protons, helium ions require only 250 MeV per nucleon, which is the lowest energy per nucleon among the light ions. This fact along with the larger biological damage to cancer cells achieved by helium ions, than that by protons, makes this species an interesting candidate for the laser driven ion source. Two mechanisms (Magnetic Vortex Acceleration and hole-boring Radiation Pressure Acceleration) of PW-class laser driven ion acceleration from liquid and gaseous helium targets are studied with the goal of producing 250 MeV per nucleon helium ion beams that meet the hadron therapy requirements. We show that He3 ions, having almost the same penetration depth as He4 with the ...

  1. Process of Coping with Radiation Therapy.

    Johnson, Jean E.; And Others

    1989-01-01

    Evaluated ability of self-regulation and emotional-drive theories to explain effects of informational intervention entailing objective descriptions of experience on outcomes of coping with radiation therapy among 84 men with prostate cancer. Consistent with self-regulation theory, similarity between expectations and experience and degree of…

  2. Radiation therapy of cancer of the lung

    The aim of this work is to present the principles of radiation therapy of cancer of the lung, according to the experience of the Institute of Oncology in Krakow. The text was designed primarily for the radiotherapists involved in the treatment of cancer of the lung, and may be used as an auxiliary textbook for those preparing for the examination in radiotherapy. (author)

  3. Electron accelerator for radiation sterilization and R and D study

    Upgrading of radiation facility located at Institute of Nuclear Chemistry and Technology in Warsaw has been initiated, with support of IAEA TC Project, towards higher technical and economical effectiveness, better operational characteristics suitable for radiation processing and research programs in order to promote in Poland the radiation technologies for sterilization medical devices and tissue grafts as well as food product hygenization and other radiation processes where high energy electrons are required. The objective of the project is 10 MeV, 15 kW linear electron accelerator equipped with microwave source based on modern klystron device TH2158 operated at frequency 2856 MHz and standing wave accelerating section. The following stages of the project have been described: electron gun construction, design of microwave system of accelerator including pulse power supply, completion and installation of necessary systems including klystron stand, pulse power supply stand, driving generator stand and waveguide system. The klystron modulator was designed with high power semiconductor HV transistor. Electron beam alignment, beam parameters evaluation and accelerator commissioning are foreseen in the final stage of the project. The better accelerator availability, more stable beam parameters, better spare parts availability, reduced exploitation costs and higher beam power are expected after successful project implementation. Implementation of the project will provide opportunity to develop skills and knowledge of the personnel engaged. It will make also possible to apply the results to another facility in Poland and other central European countries. (author)

  4. Computer models for optimizing radiation therapy

    The aim of this contribution is to outline how methods of system analysis, control therapy and modelling can be applied to simulate normal and malignant cell growth and to optimize cancer treatment as for instance radiation therapy. Based on biological observations and cell kinetic data, several types of models have been developed describing the growth of tumor spheroids and the cell renewal of normal tissue. The irradiation model is represented by the so-called linear-quadratic model describing the survival fraction as a function of the dose. Based thereon, numerous simulation runs for different treatment schemes can be performed. Thus, it is possible to study the radiation effect on tumor and normal tissue separately. Finally, this method enables a computer-assisted recommendation for an optimal patient-specific treatment schedule prior to clinical therapy. (orig.)

  5. Combined therapy of urinary bladder radiation injury

    Zaderin, V.P.; Polyanichko, M.F. (Rostovskij-na-Donu Nauchno-Issledovatel' skij Onkologicheskij Inst. (USSR))

    1982-01-01

    A scheme of therapy of radiation cystitis is suggested. It was developed on the basis of evaluation of literature and clinical data of 205 patients with radiation injury of the urinary bladder. The method is based on general and local therapy of damaged tissues by antiinflammatory drugs, anesthetics and stimulators of reparative regeneration. Severe ulcerative and incrustation cystites, refractory to conservative therapy, were treated by surgery, using antiseptics and reparation stimulators before, during and after operation. As a result, there were hardly any complications after reconstruction of the bladder with intestinal and peritoneal tissues. 104 patients (96.1%) were cured completely and ability to work was restored in 70 patients (76.9%).

  6. Non scaling fixed field gradient accelerator design for proton and carbon therapy

    The Fixed Field Alternating Gradient (FFAG) accelerators became again a subject of great interest in many accelerator physics applications, after more than fifty years of their first appearance. The original FFAG's are the 'scaling' design where particle orbits during acceleration scale with momentum. In Japan a number of scaling FFAG's have been built, or are under construction. The original designs are proposed and used in many applications: proton acceleration in medical field for cancer therapy, electron acceleration for the low (food radiation, electron demonstration ring) and high energies (future e-RHIC 10 GeV), acceleration of muons (the 'PRISM'-project in Japan), proton acceleration for the AGS upgrade at Brookhaven National Laboratory, etc. There are many advantages of the scaling FFAG with respect to the today common use of synchrotrons, cyclotrons, or linear accelerators-linacs: the magnetic field is fixed, possibility of high repetition rate. Disadvantages of the scaling FFAG are the large required aperture and large circumference. This is due to the scaling law between the orbit and momentum and the relatively large opposite bending field requirement. This proposed non-scaling design had been extensively investigated in many respects. A European proposal to build a non-scaling FFAG electron demonstration ring is in progress. Recent international CYCLOTRON conference had dedicated time for the update on the FFAG acceleration. The non-scaling FFAG's should dramatically reduce required aperture and circumferences. If the fixed magnetic field produces the linear gradient, there is a tune variation during fast acceleration and resonances are a crossed. The small dispersion function and strong focusing in this design reduces the aperture size for almost an order of magnitude with respect to standard scaling FFAG design. We present one of the possible applications of the non-scaling proton and carbon cancer therapy FFAG accelerator. The cancer proton therapy

  7. Betatron radiation from laser Wakefield acceleration in a plasma channel

    Laser Wakefield acceleration by a high-power laser pulse and a plasma has attracted lots of attention in recent years as it can generate quasi-monoenergetic high-energy electron beams and may be used for a compact x-ray source on a table-top scale. In the laser wakefield acceleration, plasma electrons can be self-injected into the acceleration phase of the wake wave and they are accelerated with an extremely high gradient in the longitudinal direction. In addition to the longitudinal acceleration, the wake wave also gives an ultra-strong focusing force in the transverse direction. As a result, the accelerated electrons execute the betatron oscillations which can produce the betatron radiation. We propose a method to increase the betatron oscillation amplitude by off-axis injection of a laser pulse into a capillary plasma waveguide. The capillary plasma waveguide has been used only for optical guiding and electron acceleration, where the transverse plasma density profile is nearly parabolic. In our work, we found that the betatron oscillation amplitude can be significantly increased by off-axis injection of the laser pulse into the capillary plasma waveguide, which can be utilized for generation of shorter wavelength X-ray radiation. In order to demonstrate the proposed idea for increasing the betatron oscillation amplitude, we performed two-dimensional (2D) particle in-cell (PIC) simulations in addition to analytical studies. (author)

  8. Radiation protection activities around the CERN accelerators

    In 1995 several operational circumstances required careful watching by the Radiation Protection Group. Most of these were linked with new or recently started CERN activities: for instance the increasing importance assumed by ISOLDE operation and the breakdowns encountered which have given rise to contamination of the target region and to activity releases. In the SPS ring, several difficulties were brought about by a toilsome installation of a new interlock system, while lead ion operation marked the end of the year, as usual, with higher radiation levels in the SPS experimental areas, despite the fact that existing shielding had been improved. Also at the end of the year, the increase of LEP beam energy to 68 GeV caused a rise of dose rate levels from synchrotron radiation. This was expected, but studies are still needed to assess the full implications for different aspects of radiation protection. On the other hand, the ageing of magnet coils and other equipment (insulators, cables, flexible pipes), aggravated by the high proton beam intensities, has resulted in an increasing frequency of failures (mainly water leaks) both at the PS and at the SPS. If the apparent trend is confirmed, difficulties could be expected in the future for two reasons: the shortage of specialized staff, some of them approaching the CERN dose limit of 15 mSv annually, who can be assigned to repair work; and the lack of spare parts to replace the damaged items. Luckily, the long cooling times following high intensity proton runs provided by the operation with heavy-ions and by the winter shutdown mitigate this situation

  9. Comparison of particle-radiation-therapy modalities

    The characteristics of dose distribution, beam alignment, and radiobiological advantages accorded to high LET radiation were reviewed and compared for various particle beam radiotherapeutic modalities (neutron, Auger electrons, p, π-, He, C, Ne, and Ar ions). Merit factors were evaluated on the basis of effective dose to tumor relative to normal tissue, linear energy transfer (LET), and dose localization, at depths of 1, 4, and 10 cm. In general, it was found that neutron capture therapy using an epithermal neutron beam provided the best merit factors available for depths up to 8 cm. The position of fast neutron therapy on the Merit Factor Tables was consistently lower than that of other particle modalities, and above only 60Co. The largest body of clinical data exists for fast neutron therapy; results are considered by some to be encouraging. It then follows that if benefits with fast neutron therapy are real, additional gains are within reach with other modalities

  10. Radiation Safety of Accelerator Facility with Regard to Regulation

    The radiation safety of accelerator facility and the status of the facilities according to licensee in Indonesia as well as lesson learned from the accidents are described. The atomic energy Act No. 10 of 1997 enacted by the Government of Indonesia which is implemented in Radiation Safety Government Regulation No. 63 and 64 as well as practice-specific model regulation for licensing request are discussed. (author)

  11. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma. (author)

  12. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    Ekstrand, K.E.; Dixon, R.L. (Wake Forest Univ., Winston-Salem, NC (USA))

    1982-03-01

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma.

  13. Recommendation of the working group commissioned by the French nuclear safety authority on stereotactic radiation therapy

    Purpose. - At the request of the French nuclear safety authority (Autorite de Surete Nucleaire, ASN) a working party of multidisciplinary experts was initiated to elaborate a report regarding propositions for the clinical practice of stereotactic radiation therapy and the related medical physics. Material and methods. - Several stereotactic radiation therapy experts were audited by the working party, especially neurosurgeons and neuro-radiologists, as well as radiation oncologists, medical physicists and radiation technologists. An international survey was conducted looking at legal requirements and guidelines concerning stereotactic radiation therapy. A national survey was conducted in France among 29 departments performing stereotactic radiation therapy. The working party report was submitted for advice to the permanent group of medical experts of ASN. Results. - Among the 13 countries who responded, very few have legal documents. Some of them are stating that stereotactic radiation therapy must be performed in a radiotherapy department and only by well-trained professionals. Guidelines describing the role of each participant have been published in the USA. In France, stereotactic radiation therapy is performed with dedicated machines or adapted linear accelerators. In 2009, within the 29 departments, 4247 patients were treated with stereotactic radiation therapy representing 4% of the patients treated with external beam radiation therapy. Intracranial lesions were: 3383 and extracranial: 864. The working party of multidisciplinary experts made 7 recommendations. The first one saying that stereotactic radiation therapy must be considered as a radiotherapy. The permanent group of medical experts is asking to modify the 'decret du 19 mars 2007' regarding 'radiosurgery'. Conclusion. - The medical benefit of stereotactic radiation therapy is well admitted and it is an increasingly used technique. This work through practical guidelines and legal propositions intends

  14. Radiation processing of liquid with low energy electron accelerator

    Radiation induced emulsion polymerization, radiation vulcanization of NR latex (RVNRL) and radiation degradation of natural polymers were selected and reviewed as the radiation processing of liquid. The characteristic of high dose rate emulsion polymerization is the occurrence of cationic polymerization. Thus, it can be used for the production of new materials that cannot be obtained by radical polymerization. A potential application will be production of polymer emulsion that can be used as water-borne UV/EB curing resins. The technology of RVNRL by γ-ray has been commercialized. RVNRL with low energy electron accelerator is under development for further vulcanization cost reduction. Vessel type irradiator will be favorable for industrial application. Radiation degradation of polysaccharides is an emerging and promising area of radiation processing. However, strict cost comparison between liquid irradiation with low energy EB and state irradiation with γ-ray should be carried out. (author)

  15. Radiation processing of liquid with low energy electron accelerator

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2003-02-01

    Radiation induced emulsion polymerization, radiation vulcanization of NR latex (RVNRL) and radiation degradation of natural polymers were selected and reviewed as the radiation processing of liquid. The characteristic of high dose rate emulsion polymerization is the occurrence of cationic polymerization. Thus, it can be used for the production of new materials that cannot be obtained by radical polymerization. A potential application will be production of polymer emulsion that can be used as water-borne UV/EB curing resins. The technology of RVNRL by {gamma}-ray has been commercialized. RVNRL with low energy electron accelerator is under development for further vulcanization cost reduction. Vessel type irradiator will be favorable for industrial application. Radiation degradation of polysaccharides is an emerging and promising area of radiation processing. However, strict cost comparison between liquid irradiation with low energy EB and state irradiation with {gamma}-ray should be carried out. (author)

  16. Prone Breast Intensity Modulated Radiation Therapy: 5-Year Results

    Osa, Etin-Osa O.; DeWyngaert, Keith [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Roses, Daniel [Department of Surgery, New York University School of Medicine, New York, New York (United States); Speyer, James [Department of Medical Oncology, New York University School of Medicine, New York, New York (United States); Guth, Amber; Axelrod, Deborah [Department of Surgery, New York University School of Medicine, New York, New York (United States); Fenton Kerimian, Maria [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Goldberg, Judith D. [Department of Population Health, New York University School of Medicine, 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, New York, New York (United States)

    2014-07-15

    Purpose: To report the 5-year results of a technique of prone breast radiation therapy delivered by a regimen of accelerated intensity modulated radiation therapy with a concurrent boost to the tumor bed. Methods and Materials: Between 2003 and 2006, 404 patients with stage I-II breast cancer were prospectively enrolled into 2 consecutive protocols, institutional trials 03-30 and 05-181, that used the same regimen of 40.5 Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.5 Gy (total dose 48 Gy). All patients were treated after segmental mastectomy and had negative margins and nodal assessment. Patients were set up prone: only if lung or heart volumes were in the field was a supine setup attempted and chosen if found to better spare these organs. Results: Ninety-two percent of patients were treated prone, 8% supine. Seventy-two percent had stage I, 28% stage II invasive breast cancer. In-field lung volume ranged from 0 to 228.27 cm{sup 3}, mean 19.65 cm{sup 3}. In-field heart volume for left breast cancer patients ranged from 0 to 21.24 cm{sup 3}, mean 1.59 cm{sup 3}. There was no heart in the field for right breast cancer patients. At a median follow-up of 5 years, the 5-year cumulative incidence of isolated ipsilateral breast tumor recurrence was 0.82% (95% confidence interval [CI] 0.65%-1.04%). The 5-year cumulative incidence of regional recurrence was 0.53% (95% CI 0.41%-0.69%), and the 5-year overall cumulative death rate was 1.28% (95% CI 0.48%-3.38%). Eighty-two percent (95% CI 77%-85%) of patients judged their final cosmetic result as excellent/good. Conclusions: Prone accelerated intensity modulated radiation therapy with a concomitant boost results in excellent local control and optimal sparing of heart and lung, with good cosmesis. Radiation Therapy Oncology Group protocol 1005, a phase 3, multi-institutional, randomized trial is ongoing and is evaluating the equivalence of a similar dose and

  17. Radiation Shielding Analysis of Electron Beam Accelerator Facility

    The objective of this technical report are to establish the radiation shielding technology of a high-energy electron accelerator to the facilities which utilize with electron beam. The technologies of electron beam irradiation(300 KeV -10 MeV) demand on the diverse areas of material processing, surface treatment, treatments on foods or food processing, improvement of metal properties, semiconductors, and ceramics, sterilization of medical goods and equipment, treatment and control of contamination and pollution, and so on. In order to acquire safety design for the protection of personnel from the radiations produced by electron beam accelerators, it is important to develop the radiation shielding analysis technology. The shielding analysis are carried out by which define source term, calculation modelling and computer calculations for 2 MeV and 10 MeV accelerators. And the shielding analysis for irradiation dump shield with 10 MeV accelerators are also performed by solving the complex 3-D geometry and long computer run time problem. The technology development of shielding analysis will be contributed to extend the further high energy accelerator development

  18. Migratory organizing pneumonitis `primed` by radiation therapy

    Bayle, J.Y.; Nesme, P.; Guerin, J.C. [Hopital de la Croix Rousse, Service de Pneumologie, Lyon (France); Bejui-Thivolet, F. [Hopital de la Croix Rousse, Laboratorie d`Anatomopatologie, Lyon (France); Loire, R. [Hopital Cardiovasculaire et Pneumologique, Universite Claude Bernard, Laboratoire d`Anatomopathologie, Lyon (France); Cordier, J.F. [Hopital Cardiovasculaire et Pneumologique, Universite Claude Bernard, Service de Pneumologie, Lyon (France)

    1995-02-01

    We report on two women presenting with cough and fever, 4 and 7 months, respectively, after starting breast radiation therapy following surgery for breast carcinoma. Chest roentgenogram and computed tomographic (CT) scan demonstrated alveolar opacities, initially limited to the pulmonary area next to the irradiated breast, but later migrating within both lungs. Intra-alveolar granulation tissue was found in transbronchial lung biopsies. Corticosteroid treatment resulted in dramatic clinical improvment, together with complete clearing of the pulmonary opacities on chest imaging. However, clinical and imaging relapses occurred when corticosteroids were withdrawn too rapidly; with further improvment when they were reintroduced. The reported cases clearly differ from radiation pneumonitis. They were fairly typical of cryptogenic organizing pneumonitis, also called idiopathic bronchiolitis obliterans organizing pneumonia, with the exception of the radiation therapy, partially affecting the lung, which had been performed within the previous months. Since focal radiation therapy involving the lung may induce diffuse bilateral lymphocytic alveolitis, we hypothesize that this may `prime` the lung to further injury, leading to cryptogenic organizing pneumonitis. (au) (26 refs.).

  19. Migratory organizing pneumonitis 'primed' by radiation therapy

    We report on two women presenting with cough and fever, 4 and 7 months, respectively, after starting breast radiation therapy following surgery for breast carcinoma. Chest roentgenogram and computed tomographic (CT) scan demonstrated alveolar opacities, initially limited to the pulmonary area next to the irradiated breast, but later migrating within both lungs. Intra-alveolar granulation tissue was found in transbronchial lung biopsies. Corticosteroid treatment resulted in dramatic clinical improvment, together with complete clearing of the pulmonary opacities on chest imaging. However, clinical and imaging relapses occurred when corticosteroids were withdrawn too rapidly; with further improvment when they were reintroduced. The reported cases clearly differ from radiation pneumonitis. They were fairly typical of cryptogenic organizing pneumonitis, also called idiopathic bronchiolitis obliterans organizing pneumonia, with the exception of the radiation therapy, partially affecting the lung, which had been performed within the previous months. Since focal radiation therapy involving the lung may induce diffuse bilateral lymphocytic alveolitis, we hypothesize that this may 'prime' the lung to further injury, leading to cryptogenic organizing pneumonitis. (au) (26 refs.)

  20. Confinement and internal structure of radiatively accelerated quasar clouds

    Weymann, R.

    1976-09-01

    The equation of transfer for Lyman ..cap alpha.. and the Lyman continuum is solved for plane-parallel slabs of hydrogen with optical depths up to 25,000 in the line center to find the radiative acceleration as a function of position in the slab. The distribution of gas pressure and density which yields a constant acceleration and which matches the prescribed external pressure on the boundaries is then found. For optical depths less than about 36, solutions are obtained for arbitrarily low ratios of external pressure to incident radiation pressure. For optical depths larger than this, solutions are possible only if this ratio exceeds a critical value, and the acceleration of the cloud goes to zero and the column density to infinity as this critical value is approached. (AIP)

  1. Confinement and internal structure of radiatively accelerated quasar clouds

    The equation of transfer for Lyman α and the Lyman continuum is solved for plane-parallel slabs of hydrogen with optical depths up to 25,000 in the line center to find the radiative acceleration as a function of position in the slab. The distribution of gas pressure and density which yields a constant acceleration and which matches the prescribed external pressure on the boundaries is then found. For optical depths less than about 36, solutions are obtained for arbitrarily low ratios of external pressure to incident radiation pressure. For optical depths larger than this, solutions are possible only if this ratio exceeds a critical value, and the acceleration of the cloud goes to zero and the column density to infinity as this critical value is approached

  2. Brachytherapy with an improved MammoSite Radiation Therapy System

    Karthik, Nanda; Keppel, Cynthia; Nazaryan, Vahagn

    2007-03-01

    Accelerated partial breast irradiation treatment utilizing the MammoSite Radiation Therapy System (MRTS) is becoming increasingly popular. Clinical studies show excellent results for disease control and localization, as well as for cosmesis. Several Phase I, II, and III clinical trials have found significant association between skin spacing and cosmetic results after treatment with MRTS. As a result, patients with skin spacing less then 7 mm are not recommended to undergo this treatment. We have developed a practical innovation to the MammoSite brachytherapy methodology that is directed to overcome the skin spacing problem. The idea is to partially shield the radiation dose to the skin where the skin spacing is less then 7 mm, thereby protecting the skin from radiation damage. Our innovation to the MRTS will allow better cosmetic outcome in breast conserving therapy (BCT), and will furthermore allow more women to take advantage of BCT. Reduction in skin radiation exposure is particularly important for patients also undergoing adjuvant chemotherapy. We will present the method and preliminary laboratory and Monte Carlo simulation results.

  3. Hyperbaric oxygen therapy for radiation cystitis

    Gakiya, Munehisa [Okinawa Prefectural Miyako Hospital, Hirara (Japan)

    1999-08-01

    We used hyperbaric oxygen therapy (HBO) on 11 patients with radiation cystitis from 1996 to 1998. The patients aged from 46 to 78 years with a mean of 64 years underwent one or more courses of HBO consisting of 20 sessions. During the 60 min HBO patients received 100% oxygen at 2.5 absolute atmosphere pressure in the Simple Hyperbaric Chamber. Hematuria improved in all patients. Cystoscopic findings of mucosal edema, redness and capillary dilatation were improved. HBO appears to be useful for radiation cystitis. (author)

  4. Study on physical penumbra of radiation therapy

    Kim, Young Bum; Whang, Woong Ku [Korea University Medical Center, Seoul (Korea, Republic of); Kim, You Hyun [Junior College of Allied Health Science, Korea University, Seoul (Korea, Republic of)

    1993-12-15

    Proper evaluation about the penumbra is very important to improve the efficacy of radiation therapy. There are two kinds of physical penumbra, geometric penumbra and transmission penumbra. In this study, we evaluated the variation of physical penumbra according to the varing energy level, changing the field size and depth. Physical penumbra width was decreased as the source size decreased, and as the SDD increased, but the consideration about the scatter radiation and mechanical stability is an important factor. For the two adjacent beams, upper collimator should be used and especially for Co-60 unit, it is efficient to use the extended collimator.

  5. Hyperbaric oxygen therapy for radiation cystitis

    We used hyperbaric oxygen therapy (HBO) on 11 patients with radiation cystitis from 1996 to 1998. The patients aged from 46 to 78 years with a mean of 64 years underwent one or more courses of HBO consisting of 20 sessions. During the 60 min HBO patients received 100% oxygen at 2.5 absolute atmosphere pressure in the Simple Hyperbaric Chamber. Hematuria improved in all patients. Cystoscopic findings of mucosal edema, redness and capillary dilatation were improved. HBO appears to be useful for radiation cystitis. (author)

  6. Radiation Hardening of LED Luminaires for Accelerator Tunnels

    Devine, James D

    2016-01-01

    This paper summarises progress made towards the radiation hardening of LED emergency luminaires for evacuation and emergency response within the underground areas of the CERN accelerator complex. The objective has been to radiation harden existing Commercial Off-The-Shelf (COTS) emergency luminaires to maximise lighting performance, without compromising IEC 60598-2-22 compliance. A systems level approach has been adopted, leading to the development of a diode bridge based AC/DC power converter. Modified COTS luminaires including this converter design have been irradiated (to 100 kGy TID using a Cobalt-60 source), with results of a subsequent photometric analysis presented. Following encouraging tests results, a reference design for the power converter has been released under the CERN Open Hardware License to encourage manufacturer adoption. The paper concludes with areas of interest for future research in further improving the radiation hardness of LED emergency lighting for accelerators with detailed studies...

  7. Characteristics of betatron radiation from direct-laser-accelerated electrons

    Huang, T. W.; Robinson, A. P. L.; Zhou, C. T.; Qiao, B.; Liu, B.; Ruan, S. C.; He, X. T.; Norreys, P. A.

    2016-06-01

    Betatron radiation from direct-laser-accelerated electrons is characterized analytically and numerically. It is shown here that the electron dynamics is strongly dependent on a self-similar parameter S (≡n/enca0 ) . Both the electron transverse momentum and energy are proportional to the normalized amplitude of laser field (a0) for a fixed value of S . As a result, the total number of radiated photons scales as a02/√{S } and the energy conversion efficiency of photons from the accelerated electrons scales as a03/S . The particle-in-cell simulations agree well with the analytical scalings. It is suggested that a tunable high-energy and high-flux radiation source can be achieved by exploiting this regime.

  8. A 600 keV electron radiation accelerator

    The authors describe a 600 keV two-body multi-functional electron and positive ion radiation accelerator based on a 400 keV Cockroft-Walton, Which was successfully used to accelerate electron and positive ion. Through test on coating solidification of decoration materials, such as colorful surface plaster plate and relief plate, and researches on metal plate, plastic plate, wood and paper coating decorations and radiation workmanship, as well as experiment of brach-linking by radiation for filling materials of petroleum pipings, it is proved that the device is reliable and stable in operation and reaches the pre-set design indexes and satisfies the requirements called for

  9. Standalone, battery powered radiation monitors for accelerator electronics

    Wijnands, T; Spiezia, G

    2009-01-01

    A technical description of the design of a new type of radiation monitors is given. The key point in the design is the low power consumption inferior to 17 mW in radiation sensing mode and inferior to 0.3 mW in standby mode. The radiation monitors can operate without any external power or signal cabling and measure and store radiation data for a maximum period of 800 days. To read the radiation data, a standard PC can be connected via a USB interface to the device at any time. Only a few seconds are required to read out a single monitor. This makes it possible to survey a large network of monitoring devices in a short period of time, for example during a stop of the accelerator.

  10. Response of radiation detectors in electron accelerator environment

    Full text: Due to the complex nature of radiation field present in high-energy electron accelerators and in associated systems, radiation measurements and interpretation of the results become a difficult task. In the present paper response of radiation instruments due to pulsed radiation of different duty cycle, radio frequency (RF) and low frequency (LF) interference from radio frequency generators (eg. magnetron) and associated systems are studied and the results are presented. The results show that gas filled detectors operated in the multiplicative region (eg. GM tube) severely underestimate the radiation field at very low duty cycles. The response is found to improve as the duty cycle is increased. RF, LF and magnetic field interference also is studied and the results are discussed

  11. Breakdown of Acceleration Waves in Radiative Magneto-fluids

    Arisudan Rai

    2003-10-01

    Full Text Available The problem of propagation of acceleration waves in an optically thick medium of electrically conducting fluid has been dealt with. During propagation of the waves, the effects of radiation pressure, radiation energy density, and heat transfer through thermal radiation and thermal conduction have been taken into account. The growth equation for the variation of amplitude of the wave has been derived and solved. It has been concluded that all the compressive waves with initial amplitudes greater than a critical value will grow and terminate into a shock wave due to nonlinear steepening, while all expansion waves will decay out. Acritical stage, when the compressive wave will either grow or decay, has also been discussed. The effects of radiation pressure and radiative heat transfer on the shock formation have been discussed and analysed.

  12. Radiation damage to accelerator components of SPring-8 storage ring

    Radiation damage to the accelerator components of the SPring-8 storage ring became serious after about four years of operation. Some rubber hoses were broken, resulting in water leakage, and some of the Synflex tubes, interlock cables, power cable covers, and so forth became damaged. Measurement of the radiation levels using GafChromic film and TLD showed that the maximum integrated radiation dose around the hoses at normal cell was 3.9x105Gy. The main radiation sources were the crotches and absorbers. Although there were two crotches and four absorbers in each of the 44 cells, two absorbers in particular caused serious radiation damage. Lead-plate shielding was installed around these absorbers to shield the nearby components

  13. Radiation therapy for head and neck cancers

    Radiation therapy may be indicated for larger invasive tumors of the head and neck that may be difficult to surgically excise or for which surgery would be significantly disfiguring. Previous studies of oral squamous cell carcinomas indicate that it should be possible to control approximately 80% of all but the most advanced local or locoregional tumors. Aggressive radiation therapy to total doses of 56 Gy or greater may be required. That can be done by using smaller doses per fraction and gradually reducing the size of the field so that the highest dose is given only to the tumor with a relatively tight margin. Malignant melanomas can be controlled locally apparently with a few large fractions. Metastatic disease limits survival; therefore, some type of systemic therapy seems to be needed to improve survival of those patients. Canine oral fibrosarcomas require a very high dose for a reasonable probability of control. It seems that a dose of 56 Gy given in 3.3 Gy fractions might provide local control of 50% of the tumors. It is likely that a combination of surgery and radiation would significantly improve the probability for control. Oral squamous cell carcinomas of cats must also be treated very aggressively to improve local control. Tumors of the nasal cavity are usually very large and invasive at the time of diagnosis. Radiation therapy has been shown to be effective in some instances. It is possible that with better definition of the tumor through computerized tomography imaging and improved treatment planning, control of these difficult to manage nasal tumors can be improved

  14. Lacrimal gland lymphoma: Role of radiation therapy

    Natasha Townsend; Aruna Turaka; Smith, Mitchell R.

    2012-01-01

    Background: To report the clinical and treatment outcome of patients with lacrimal gland lymphoma (LGL) treated with radiation therapy (RT) at Fox Chase Cancer Center, Philadelphia, PA, USA. Materials and Methods: Institutional review board approved retrospective chart review of eight patients and literature review. Results: The study patients included six males and two females with a mean age of 70 years (range 58-88 years). The mean follow-up period was 23 months (range 3–74 months). Four p...

  15. Perspectives of radiation therapy in benign diseases

    Purpose: the numbers of patients with nonmalignant diseases referred for radiation therapy had to be evaluated for the last 4 years. Patients and methods: in the years 2002, 2004, and 2005 radiation therapy was performed in 61, 40, and 26 patients, respectively. Regularly, more women than men were treated, median age annually was 57, 54, and 55 years, respectively (table 1). The radiotherapy scheme was not modified within the evaluated period. Results: the proportion of nonmalignant diseases among all patients treated decreased from 4.7% in 2002 to 3.3% in 2004 and 2.2% in 2005, respectively. A shift was noticed toward the treatment of four main diseases (endocrine orbitopathy, prevention of heterotopic ossification, meningeoma, tendinitis, table 2). The number of referring physicians decreased from 19 to six. Conclusion: due to administrative restrictions for treatment in hospitals, budget restrictions in private practices and lasting, insufficient revenues for radiotherapy in nonmalignant diseases, radiation therapy for the entire group of benign diseases is endangered. (orig.)

  16. Radiation Therapy in Elderly Skin Cancer

    Kim, Jin Hee [Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2008-06-15

    To evaluate the long term results (local control, survival, failure, and complications) after radiation therapy for skin cancer in elderly patients. The study spanned from January 1990 to October 2002. Fifteen elderly patients with skin cancer were treated by radiotherapy at the Keimyung University Dongsan Medical Center. The age distribution of the patients surveyed was 72 to 95 years, with a median age of 78.8 years. The pathologic classification of the 15 patients included squamous cell carcinoma (10 patients), basal cell carcinoma (3 patients), verrucous carcinoma (1 patient) and skin adnexal origin carcinoma (1 patient). The most common tumor location was the head (13 patients). The mean tumor diameter was 4.9 cm (range 2 to 9 cm). The radiation dose was delivered via an electron beam of 6 to 15 MeV. The dose range was adjusted to the tumor diameter and depth of tumor invasion. The total radiation dose ranged from 50{approx}80 Gy (mean: 66 Gy) with a 2 Gy fractional dose prescribed to the 80% isodose line once a day and 5 times a week. One patient with lymph node metastasis was treated with six MV photon beams boosted with electron beams. The length of the follow-up periods ranged from 10 to 120 months with a median follow-up period of 48 months. The local control rates were 100% (15/15). In addition, the five year disease free survival rate (5YDFS) was 80% and twelve patients (80%) had no recurrence and skin cancer recurrence occurred in 3 patients (20%). Three patients have lived an average of 90 months (68{approx}120 months) without recurrence or metastasis. A total of 9 patients who died as a result of other causes had a mean survival time of 55.8 months after radiation therapy. No severe acute or chronic complications were observed after radiation therapy. Only minor complications including radiation dermatitis was treated with supportive care. The results suggest that radiation therapy is an effective and safe treatment method for the treatment of skin

  17. Accelerator Based Neutron Beams for Neutron Capture Therapy

    Yanch, Jacquelyn C.

    2003-04-11

    The DOE-funded accelerator BNCT program at the Massachusetts Institute of Technology has resulted in the only operating accelerator-based epithermal neutron beam facility capable of generating significant dose rates in the world. With five separate beamlines and two different epithermal neutron beam assemblies installed, we are currently capable of treating patients with rheumatoid arthritis in less than 15 minutes (knee joints) or 4 minutes (finger joints) or irradiating patients with shallow brain tumors to a healthy tissue dose of 12.6 Gy in 3.6 hours. The accelerator, designed by Newton scientific Incorporated, is located in dedicated laboratory space that MIT renovated specifically for this project. The Laboratory for Accelerator Beam Applications consists of an accelerator room, a control room, a shielded radiation vault, and additional laboratory space nearby. In addition to the design, construction and characterization of the tandem electrostatic accelerator, this program also resulted in other significant accomplishments. Assemblies for generating epithermal neutron beams were designed, constructed and experimentally evaluated using mixed-field dosimetry techniques. Strategies for target construction and target cooling were implemented and tested. We demonstrated that the method of submerged jet impingement using water as the coolant is capable of handling power densities of up to 6 x 10(sup 7) W/m(sup 2) with heat transfer coefficients of 10(sup 6)W/m(sup 2)-K. Experiments with the liquid metal gallium demonstrated its superiority compared with water with little effect on the neutronic properties of the epithermal beam. Monoenergetic proton beams generated using the accelerator were used to evaluate proton RBE as a function of LET and demonstrated a maximum RBE at approximately 30-40 keV/um, a finding consistent with results published by other researchers. We also developed an experimental approach to biological intercomparison of epithermal beams and

  18. Accelerator Based Neutron Beams for Neutron Capture Therapy

    The DOE-funded accelerator BNCT program at the Massachusetts Institute of Technology has resulted in the only operating accelerator-based epithermal neutron beam facility capable of generating significant dose rates in the world. With five separate beamlines and two different epithermal neutron beam assemblies installed, we are currently capable of treating patients with rheumatoid arthritis in less than 15 minutes (knee joints) or 4 minutes (finger joints) or irradiating patients with shallow brain tumors to a healthy tissue dose of 12.6 Gy in 3.6 hours. The accelerator, designed by Newton scientific Incorporated, is located in dedicated laboratory space that MIT renovated specifically for this project. The Laboratory for Accelerator Beam Applications consists of an accelerator room, a control room, a shielded radiation vault, and additional laboratory space nearby. In addition to the design, construction and characterization of the tandem electrostatic accelerator, this program also resulted in other significant accomplishments. Assemblies for generating epithermal neutron beams were designed, constructed and experimentally evaluated using mixed-field dosimetry techniques. Strategies for target construction and target cooling were implemented and tested. We demonstrated that the method of submerged jet impingement using water as the coolant is capable of handling power densities of up to 6 x 10(sup 7) W/m(sup 2) with heat transfer coefficients of 10(sup 6)W/m(sup 2)-K. Experiments with the liquid metal gallium demonstrated its superiority compared with water with little effect on the neutronic properties of the epithermal beam. Monoenergetic proton beams generated using the accelerator were used to evaluate proton RBE as a function of LET and demonstrated a maximum RBE at approximately 30-40 keV/um, a finding consistent with results published by other researchers. We also developed an experimental approach to biological intercomparison of epithermal beams and

  19. Cardiac complications of radiation therapy to the chest organs in cancer patients: the problems of early diagnosis, follow up and rehabilitation. A case discussion

    The original findings shown the character and range of complications in the cardiovascular system at radiation therapy both using a gamma-therapy unit and a linear accelerator. The questions of development of standards of diagnosis and treatment of cardiac complications of radiation therapy are discussed. A case is described

  20. Proposed method for internal electron therapy based on high-intensity laser acceleration

    Tepper, Michal; Barkai, Uri; Gannot, Israel

    2015-05-01

    Radiotherapy is one of the main methods to treat cancer. However, due to the propagation pattern of high-energy photons in tissue and their inability to discriminate between healthy and malignant tissues, healthy tissues may also be damaged, causing undesired side effects. A possible method for internal electron therapy, based on laser acceleration of electrons inside the patient's body, is suggested. In this method, an optical waveguide, optimized for high intensities, is used to transmit the laser radiation and accelerate electrons toward the tumor. The radiation profile can be manipulated in order to create a patient-specific radiation treatment profile by changing the laser characteristics. The propagation pattern of electrons in tissues minimizes the side effects caused to healthy tissues. A simulation was developed to demonstrate the use of this method, calculating the trajectories of the accelerated electron as a function of laser properties. The simulation was validated by comparison to theory, showing a good fit for laser intensities of up to 2×1020 (W/cm2), and was then used to calculate suggested treatment profiles for two tumor test cases (with and without penetration to the tumor). The results show that treatment profiles can be designed to cover tumor area with minimal damage to adjacent tissues.

  1. Radiation therapy for unresected gastric lymphoma

    Six consecutive patients with unresected gastric lymphoma which were treated by radiation therapy between November 1976 and March 1989 were reviewed. Radiation therapy was performed using involved fields, total radiation dosages of which ranged from 25.2 to 36 Gy (mean, 29.3 Gy). Five out of the 6 patients were treated with chemotherapy combined with radiation. Regimen of the chemotherapy was CHOP (cyclophophamide, adriamycin, vincristine and prednisone) in most cases. Three out of the 6 underwent probe laparotomy, but the tumors were diagnosed as unresectable due to locally invading the adjacent structures. They were treated by chemo-radiotherapy and 2 of them are surviving as of the present study (40 and 116 months). The other 3 patients were diagnosed as with clinical stage IV disease and 2 of them were successfully treated with chemo-radiotherapy (21 and 66 months, surviving). These data suggest that unresected gastric lymphomas, which are locally advanced or stage IV disease, are treated by chemo-radiotherapy with high curability without any serious complications. (author)

  2. Radiation safety interlock system at Indus accelerator complex

    A Radiation Safety Interlock System (a part of Radiation Safety System) that ensures protection of personnel during the facility operation from radiation hazards induced by electron beam and synchrotron radiation has been in operation very effectively for over a decade at Indus Accelerator complex (IAC). Radiation Safety Interlock System (RSIS) consists of two parts - Safety Interlock Unit (SIU) and Mode Selection Unit (MSU). Separate Safety Interlock Units are provided for four machine areas of IAC, namely Microtron and Booster, Indus-1 storage ring, Indus-1 user hall and Indus-2 storage ring. The efficacy of the Safety Interlock Units of Indus-1 user hall, Indus-1 storage ring and Indus-2 storage ring is governed by the operation modes that are selected through Mode Selection Unit. RSIS has been modified during past 1 and 1/2 year by addition of new interlock features and changes in the final beam control scheme. Machine Safety Interlock System (MSIS) was also interlocked with RSIS to facilitate termination of machine operation in case of any unsafe condition of Indus-2 systems. This paper describes the design philosophy, recent modifications, implementation and future upgrade plans of the present Radiation Safety Interlock Systems at Indus accelerator complex. (author)

  3. Chronic neuroendocrinological sequelae of radiation therapy

    Sklar, C.A. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Constine, L.S. [Univ. of Rochester Medical Center, Rochester, NY (United States)

    1995-03-30

    A variety of neuroendocrine disturbances are observed following treatment with external radiation therapy when the hypothalamic-pituitary axis (HPA) is included in the treatment field. Radiation-induced abnormalities are generally dose dependent and may develop many years after irradiation. Growth hormone deficiency and premature sexual development can occur following doses as low as 18 Gy fractionated radiation and are the most common neuroendocrine problems noted in children. Deficiency of gonadotropins, thyroid stimulating hormone, and adrenocorticotropin are seen primarily in individuals treated with > 40 Gy HPA irradiation. Hyperprolactinemia can be seen following high-dose radiotherapy (>40 Gy), especially among young women. Most neuroendocrine disturbances that develop as a result of HPA irradiation are treatable; patients at risk require long-term endocrine follow-up. 23 refs., 6 figs., 2 tabs.

  4. Chronic neuroendocrinological sequelae of radiation therapy

    A variety of neuroendocrine disturbances are observed following treatment with external radiation therapy when the hypothalamic-pituitary axis (HPA) is included in the treatment field. Radiation-induced abnormalities are generally dose dependent and may develop many years after irradiation. Growth hormone deficiency and premature sexual development can occur following doses as low as 18 Gy fractionated radiation and are the most common neuroendocrine problems noted in children. Deficiency of gonadotropins, thyroid stimulating hormone, and adrenocorticotropin are seen primarily in individuals treated with > 40 Gy HPA irradiation. Hyperprolactinemia can be seen following high-dose radiotherapy (> 40 Gy), especially among young women. Most neuroendocrine disturbances that develop as a result of HPA irradiation are treatable; patients at risk require long-term endocrine follow-up

  5. Microscopic Processes On Radiation from Accelerated Particles in Relativistic Jets

    Nishikawa, K.-I.; Hardee, P. E.; Mizuno, Y.; Medvedev, M.; Zhang, B.; Sol, H.; Niemiec, J.; Pohl, M.; Nordlund, A.; Fredriksen, J.; Lyubarsky, Y.; Hartmann, D. H.; Fishman, G. J.

    2009-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microquasar systems usually have power-law emission spectra. Recent PIC simulations of relativistic electron-ion (electro-positron) jets injected into a stationary medium show that particle acceleration occurs within the downstream jet. In the collisionless relativistic shock particle acceleration is due to plasma waves and their associated instabilities (e.g., the Buneman instability, other two-streaming instability, and the Weibel (filamentation) instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The jitter'' radiation from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  6. The role of a prone setup in breast radiation therapy

    Nelly eHuppert

    2011-10-01

    Full Text Available Most patients undergoing breast conservation therapy (BCT receive radiotherapy in the supine position. Historically, prone breast irradiation has been advocated for women with large pendulous breasts in order to decrease acute and late toxicities. With the advent of CT planning, the prone technique has become both feasible and reproducible. It was shown to be advantageous not only for women with larger breasts but in most patients since it consistently reduces, if not eliminates, the inclusion of heart and lung within the field. The prone setup has been accepted as the best localizing position for both MRI and stereotactic biopsy, but its adoption has been delayed in radiotherapy. New technological advances including image-modulated radiation therapy (IMRT and image-guided radiation therapy (IGRT have made possible the exploration of accelerated fractionation schemes with a concomitant boost to the tumor bed in the prone position, along with better imaging and verification of reproducibility of patient setup. This review describes some of the available techniques for prone breast radiotherapy and the available experience in their application. The NYU prone breast radiotherapy approach is discussed, including a summary of the results from several prospective trials.

  7. Nonthermal Particle Acceleration and Radiation in Relativistic Magnetic Reconnection

    Werner, Gregory

    2015-11-01

    Many spectacular and violent phenomena in the high-energy universe exhibit nonthermal radiation spectra, from which we infer power-law energy distributions of the radiating particles. Relativistic magnetic reconnection, recognized as a leading mechanism of nonthermal particle acceleration, can efficiently transfer magnetic energy to energetic particles. We present a comprehensive particle-in-cell study of particle acceleration in 2D relativistic reconnection in both electron-ion and pair plasmas without guide field. We map out the power-law index α and the high-energy cutoff of the electron energy spectrum as functions of three key parameters: the system size (and initial layer length) L, the ambient plasma magnetization σ, and the ion/electron mass ratio (from 1 to 1836). We identify the transition between small- and large-system regimes: for small L, the system size affects the slope and extent of the high-energy spectrum, while for large enough L, α and the cutoff energy are independent of L. We compare high energy particle spectra and radiative (synchrotron and inverse Compton) signatures of the electrons, for pair and electron-ion reconnection. The latter cases maintain highly relativistic electrons, but include a range of different magnetizations yielding sub- to highly-relativistic ions. Finally, we show how nonthermal acceleration and radiative signatures alter when the radiation back-reaction becomes important. These results have important implications for assessing the promise and the limitations of relativistic reconnection as an astrophysically-important particle acceleration mechanism. This work is funded by NSF, DOE, and NASA.

  8. Electron string ion sources for carbon ion cancer therapy accelerators

    Boytsov, A. Yu.; Donets, D. E.; Donets, E. D.; Donets, E. E.; Katagiri, K.; Noda, K.; Ponkin, D. O.; Ramzdorf, A. Yu.; Salnikov, V. V.; Shutov, V. B.

    2015-08-01

    The type of the Electron String Ion Sources (ESIS) is considered to be the appropriate one to produce pulsed C4+ and C6+ ion beams for cancer therapy accelerators. In fact, the new test ESIS Krion-6T already now provides more than 1010 C4+ ions per pulse and about 5 × 109 C6+ ions per pulse. Such ion sources could be suitable to apply at synchrotrons. It has also been found that Krion-6T can provide more than 1011 C6+ ions per second at the 100 Hz repetition rate, and the repetition rate can be increased at the same or larger ion output per second. This makes ESIS applicable at cyclotrons as well. ESIS can be also a suitable type of ion source to produce the 11C radioactive ion beams. A specialized cryogenic cell was experimentally tested at the Krion-2M ESIS for pulse injection of gaseous species into the electron string. It has been shown in experiments with stable methane that the total conversion efficiency of methane molecules to C4+ ions reached 5%÷10%. For cancer therapy with simultaneous irradiation and precise dose control (positron emission tomography) by means of 11C, transporting to the tumor with the primary accelerated 11C4+ beam, this efficiency is preliminarily considered to be large enough to produce the 11C4+ beam from radioactive methane and to inject this beam into synchrotrons.

  9. Electron accelerators for radiation processing: Criterions of selection and exploitation

    The progress in accelerator technology is tightly attached to the continuously advanced development in many branches of technical activity. Although the present level of accelerators development can satisfy most of the commercial requirements, this field continues to expand and improve quality by offering efficient, cheap, reliable, high average beam power commercial units. Accelerator construction must be a compromised between size, efficiency and cost with respect to the field of its application. High power accelerators have been developed to meet specific demands of flue gas treatment and other high throughput to increase the capacity of the progress and reduced unit cost of operation. Automatic control, reliability and reduced maintenance, adequate adoption to process conditions, suitable electron energy and beam power are the basic features of modern accelerator construction. Accelerators have the potential to serve as industrial radiation sources and eventually may replace the isotope sources in future. Electron beam plants can transfer much higher amounts of energy into the irradiated objects than other types of facilities including gamma plants. This provides the opportunity to construct technological lines with high capacity that are more technically and economically suitable with high throughputs, short evidence time and grate versatility

  10. Combined preoperative therapy for oral cancer with nedaplatin and radiation

    Adachi, Masatoshi; Shibata, Akihiko; Hayashi, Munehiro [Nippon Dental Univ., Tokyo (Japan). Hospital] (and others)

    2002-03-01

    We performed preoperative combined therapy using nedaplatin (CDGP) and radiation in 12 patients with squamous cell carcinoma originating from the oral cavity and maxillary sinus, and examined for any adverse events that may have occurred during this therapeutic regimen. Regarding the irradiation, external irradiation utilizing a 6 MV linac (linear accelerator) at a dose of 2.0 Gy/day was performed 5 times a week, with the target total radiation dose set at 40 Gy. In addition, CDGP was intravenously administered 30 minutes before irradiation at a dose of 5 mg/m{sup 2}/day. Mucositis was observed in all 12 subjects, however, the severity was observed to be grade 1-2 with no major differences in comparison to the patients given standard radiation monotherapy. Two subjects developed grade 3 leucopenia and were thus given granulocyte colony stimulating factor (G-CSF). In addition, grade 2 and grade 3 thrombocytopenia were both observed in one subject each. The subject with grade 3 thrombocytopenia required a platelet transfusion during surgery. No marked changes in serum creatinine levels were noted. These findings are therefore considered to provide evidence supporting the safety of this combination therapy. (author)

  11. The value of radiation therapy for pituitary tumors

    Following points are discussed in this review. 1) Historical review of our previous therapeutic management. 2) Classification of pituitary adenomas. 3) Clinical analysis of my recent 58 cases. 4) Verification of usefulness of postoperative irradiation which achieved to increase in local control rate. 5) Authoritativeness of radiotherapy. In general, 3 to 4 portal technique or arc therapy were employed. The lateral opposing field technique was avoid to use. The recommended doses using linear accelerator x-ray technique is approximately 5000 cGy in 5 weeks. To prevent radiation hazard; (1) examiner should not use technique of two opposed fields, (2) total doses should not exceed 5000 cGy in 5 to 6 weeks and the use of daily fractions should not exceed 200 cGy. 6) Correlation of hormone secreting tumors and radiation therapy. 7) Problem of radiosurgery and heavy particle. 8) Countermeasure for recurrence cases. 9) Problem of side effects of radiotherapy and its precaution. Complication of radiation for pituitary adenoma found that the significant side effects are negligibly small in recent years. 10) Pituitary tumor are originally slow growing and benign tumor, therefore the response to irradiation takes long time to elapse for final evaluation. For instance, over 80 to 90% of acromegaly patients respond HGH successfully, but this may require from one to several years. 11) Conclusion. (author)

  12. Radiation Therapy for the Management of Brain Metastases.

    Garrett, Matthew D; Wu, Cheng-Chia; Yanagihara, Ted K; Jani, Ashish; Wang, Tony J C

    2016-08-01

    Brain metastases are the most common malignant intracranial tumors and carry a poor prognosis. The management of brain metastases may include a variety of treatment modalities including surgical resection, radiation therapy, and/or systemic therapy. The traditional treatment for brain metastasis involved whole brain irradiation. However, improved systemic control of primary cancers has led to longer survival for some groups of patients and there is increasing need to consider the late effects of radiation to the entire brain. With advances in imaging and radiation treatment planning and delivery stereotactic radiosurgery has become more frequently utilized and may be delivered through Gamma Knife Stereotactic Radiosurgery or linear accelerator-based systems. Furthermore, experience in treating thousands of patients on clinical trials has led to diagnosis-specific prognostic assessment systems that help guide our approach to the management of this common clinical scenario. This review provides an overview of the literature supporting radiotherapy for brain metastasis and an update on current radiotherapeutic options that is tailored for the nonradiation oncologist. PMID:27213494

  13. Combined preoperative therapy for oral cancer with nedaplatin and radiation

    We performed preoperative combined therapy using nedaplatin (CDGP) and radiation in 12 patients with squamous cell carcinoma originating from the oral cavity and maxillary sinus, and examined for any adverse events that may have occurred during this therapeutic regimen. Regarding the irradiation, external irradiation utilizing a 6 MV linac (linear accelerator) at a dose of 2.0 Gy/day was performed 5 times a week, with the target total radiation dose set at 40 Gy. In addition, CDGP was intravenously administered 30 minutes before irradiation at a dose of 5 mg/m2/day. Mucositis was observed in all 12 subjects, however, the severity was observed to be grade 1-2 with no major differences in comparison to the patients given standard radiation monotherapy. Two subjects developed grade 3 leucopenia and were thus given granulocyte colony stimulating factor (G-CSF). In addition, grade 2 and grade 3 thrombocytopenia were both observed in one subject each. The subject with grade 3 thrombocytopenia required a platelet transfusion during surgery. No marked changes in serum creatinine levels were noted. These findings are therefore considered to provide evidence supporting the safety of this combination therapy. (author)

  14. Cherenkov Video Imaging Allows for the First Visualization of Radiation Therapy in Real Time

    Purpose: To determine whether Cherenkov light imaging can visualize radiation therapy in real time during breast radiation therapy. Methods and Materials: An intensified charge-coupled device (CCD) camera was synchronized to the 3.25-μs radiation pulses of the clinical linear accelerator with the intensifier set × 100. Cherenkov images were acquired continuously (2.8 frames/s) during fractionated whole breast irradiation with each frame an accumulation of 100 radiation pulses (approximately 5 monitor units). Results: The first patient images ever created are used to illustrate that Cherenkov emission can be visualized as a video during conditions typical for breast radiation therapy, even with complex treatment plans, mixed energies, and modulated treatment fields. Images were generated correlating to the superficial dose received by the patient and potentially the location of the resulting skin reactions. Major blood vessels are visible in the image, providing the potential to use these as biological landmarks for improved geometric accuracy. The potential for this system to detect radiation therapy misadministrations, which can result from hardware malfunction or patient positioning setup errors during individual fractions, is shown. Conclusions: Cherenkoscopy is a unique method for visualizing surface dose resulting in real-time quality control. We propose that this system could detect radiation therapy errors in everyday clinical practice at a time when these errors can be corrected to result in improved safety and quality of radiation therapy

  15. Radiation vulcanization of natural rubber latex with low energy accelerator

    The radiation vulcanization of natural rubber latex (RVNRL) with the recently installed electron beam (EB) pilot plant at Takasaki Radiation Chemistry Research Establishment, Takasaki, Japan has been discussed. The accelerating voltage and beam current of the plant are 250 kV and 10 mA respectively. The plant has a reaction vessel with the capacity of 18 liters latex to irradiate at a time. In order to obtain a suitable setting of experimental for RVNRL under EB of the plant the parameters such as irradiation time, defoamer concentration, volume of latex, beam current etc. are being optimized by varying the individual parameter at a constant set of the other variables. (author)

  16. Nonthermal radiation from relativistic electrons accelerated at spherically expanding shocks

    Kang, Hyesung

    2014-01-01

    We study the evolution of the energy spectrum of cosmic-ray electrons accelerated at spherically expanding shocks with low Mach numbers and the ensuing spectral signatures imprinted in radio synchrotron emission. Time-dependent simulations of diffusive shock acceleration (DSA) of electrons in the test-particle limit have been performed for spherical shocks with the parameters relevant for typical shocks in the intracluster medium. The electron and radiation spectra at the shock location can be described properly by the test-particle DSA predictions with the instantaneous shock parameters. However, the volume integrated spectra of both electrons and radiation deviate significantly from the test-particle power-laws, because the shock compression ratio and the flux of injected electrons at the shock gradually decrease as the shock slows down in time. So one needs to be cautious about interpreting observed radio spectra of evolving shocks by simple DSA models in the test-particle regime.

  17. Multi-dimensional effects in radiation pressure acceleration of ions

    A laser carries momentum. On reflection from an ultra-thin overdense plasma foil, it deposits recoil momentum on the foil, i.e. exerts radiation pressure on the foil electrons and pushes them to the rear. The space charge field thus created takes the ions along, accelerating the electron-ion double layer as a single unit. When the foil has surface ripple, of wavelength comparable to laser wavelength, the radiation pressure acts non-uniformly on the foil and the perturbation grows as Reyleigh-Taylor (RT) instability as the foil moves. The finite spot size of the laser causes foil to bend. These effects limit the quasi-mono energy acceleration of ions. Multi-ion foils, e.g., diamond like carbon foil embedded with protons offer the possibility of suppressing RT instability

  18. Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

    Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm3 increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versus radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy. - Highlights: • Radiation changes tumor endothelial cells to fibroblasts. • Radio-resistant tumors contain collagen deposits, especially in tumor vessels. • Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy. • Pirfenidone reduces radiation-induced collagen deposits in tumors

  19. Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

    Choi, Seo-Hyun; Nam, Jae-Kyung; Jang, Junho; Lee, Hae-June, E-mail: hjlee@kcch.re.kr; Lee, Yoon-Jin, E-mail: yjlee8@kcch.re.kr

    2015-06-26

    Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm{sup 3} increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versus radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy. - Highlights: • Radiation changes tumor endothelial cells to fibroblasts. • Radio-resistant tumors contain collagen deposits, especially in tumor vessels. • Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy. • Pirfenidone reduces radiation-induced collagen deposits in tumors.

  20. Big data and comparative effectiveness research in radiation oncology: synergy and accelerated discovery

    Daniel eTrifiletti

    2015-12-01

    Full Text Available Several advances in large data set collection and processing have the potential to provide a wave of new insights and improvements in the use of radiation therapy for cancer treatment. The era of electronic health records, genomics, and improving information technology resources creates the opportunity to leverage these developments to create a learning healthcare system that can rapidly deliver informative clinical evidence. By merging concepts from comparative effectiveness research with the tools and analytic approaches of big data, it is hoped that this union will accelerate discovery, improve evidence for decision-making, and increase the availability of highly relevant, personalized information. This combination offers the potential to provide data and analysis that can be leveraged for ultra-personalized medicine and high quality, cutting-edge radiation therapy.

  1. Acceleration radiation, transition probabilities, and trans-Planckian physics

    Agulló, Iván; Navarro-Salas, José; Olmo, Gonzalo J.; Parker, Leonard

    2010-01-01

    An important question in the derivation of the acceleration radiation, which also arises in Hawking's derivation of black hole radiance, is the need to invoke trans-Planckian physics for the quantum field that originates the created quanta. We point out that this issue can be further clarified by reconsidering the analysis in terms of particle detectors, transition probabilities, and local two-point functions. By writing down separate expressions for the spontaneous- and induced-transition pr...

  2. External beam radiation therapy for prostate cancer

    Purpose/Objectives: The intent of this course is to review the issues involved in the management of non-metastatic adenocarcinoma of the prostate. -- The value of pre-treatment prognostic factors including stage, grade and PSA value will be presented, and their value in determining therapeutic strategies will be discussed. -- Controversies involving the simulation process and treatment design will be presented. The value of CT scanning, Beams-Eye View, 3-D planning, intravesicle, intraurethral and rectal contrast will be presented. The significance of prostate and patient movement and strategies for dealing with them will be presented. -- The management of low stage, low to intermediate grade prostate cancer will be discussed. The dose, volume and timing of irradiation will be discussed as will the role of neo-adjuvant hormonal therapy, neutron irradiation and brachytherapy. The current status of radical prostatectomy and cryotherapy will be summarized. Treatment of locally advanced, poorly differentiated prostate cancer will be presented including a discussion of neo-adjuvant and adjuvant hormones, dose-escalation and neutron irradiation. -- Strategies for post-radiation failures will be presented including data on cryotherapy, salvage prostatectomy and hormonal therapy (immediate, delayed and/or intermittent). New areas for investigation will be reviewed. -- The management of patients post prostatectomy will be reviewed. Data on adjuvant radiation and therapeutic radiation for biochemical or clinically relapsed patients will be presented. This course hopes to present a realistic and pragmatic overview for treating patients with non-metastatic prostatic cancer

  3. Palliative radiation therapy for multiple myeloma

    Radiation therapy is a useful palliative modality for refractory lesions of multiple myeloma. It has been reported that total doses of 10 to 20 Gy are usually adequate to obtain some degree of pain relief. However, there are many patients who need additional doses to obtain sufficient pain relief. In this study. we retrospectively analyzed the records of patients with multiple myeloma irradiated at our department, in an attempt to develop an effective treatment policy for this disease. Twenty-nine patients with 53 lesions were treated between 1968 and 1993. Total irradiation doses were 4 to 60 Gy (median 40 Gy) with daily fractions of 2 Gy or less, and 16 to 51 Gy (median 30 Gy) with daily fractions greater than 2 Gy. Evaluated were 59 symptoms, including pain (68%), neurological abnormalities (15%), and masses (28%). Symptomatic remission was obtained in 33 of 36 (92%) lesions with pain, 6 of 8 (75%) with neurological abnormalities, and 13 of 15 (87%) mass lesions. Pain was partially relieved at a median TDF of 34, and completely at a median TDF of 66 (equivalent to 40-42 Gy with daily fractions of 2 Gy). Radiation therapy is an effective and palliative treatment method for symptomatic multiple myeloma. However, the treatment seems to require higher radiation doses than those reported to obtain adequate relief of symptoms. (author)

  4. State of the art of radiation therapy for esophageal cancer

    Radiation therapy has a critical role in the treatment of esophageal cancer. To improve the treatment outcome of radiotherapy, not only strengthening the treatment intensity but also decreasing the long term toxicity is needed. To reduce the long term cardiopulmonary toxicity of chemoradiation, JCOG is now running a clinical trial which combines three dimensional conformal radiation therapy (3D-CRT) and mild irradiation dose. New techniques of radiation therapy, such as intensity modulated radiation therapy (IMRT) or particle therapy are also promising in both treatment intensity and decreased toxicity. (author)

  5. Memory and survival after microbeam radiation therapy

    Background: Disturbances of memory function are frequently observed in patients with malignant brain tumours and as adverse effects after radiotherapy to the brain. Experiments in small animal models of malignant brain tumour using synchrotron-based microbeam radiation therapy (MRT) have shown a promising prolongation of survival times. Materials and methods: Two animal models of malignant brain tumour were used to study survival and memory development after MRT. Thirteen days after implantation of tumour cells, animals were submitted to MRT either with or without adjuvant therapy (buthionine-SR-sulfoximine = BSO or glutamine). We used two orthogonal 1-cm wide arrays of 50 microplanar quasiparallel microbeams of 25 μm width and a center-to-center distance of about 200 μm, created by a multislit collimator, with a skin entrance dose of 350 Gy for each direction. Object recognition tests were performed at day 13 after tumour cell implantation and in monthly intervals up to 1 year after tumour cell implantation. Results: In both animal models, MRT with and without adjuvant therapy significantly increased survival times. BSO had detrimental effects on memory function early after therapy, while administration of glutamine resulted in improved memory

  6. Particle acceleration, magnetization and radiation in relativistic shocks

    Derishev, Evgeny V

    2015-01-01

    What are the mechanisms of particle acceleration and radiation, as well as magnetic field build up and decay in relativistic shocks are open questions with important implications to various phenomena in high energy astrophysics. While the Weibel instability is possibly responsible for magnetic field build up and diffusive shock acceleration is a model for acceleration, both have problems and current PIC simulation show that particles are accelerated only under special conditions and the magnetic field decays on a short length scale. We present here a novel model for the structure and the emission of highly relativistic collisionless shocks. The model takes into account (and is based on) non-local energy and momentum transport across the shock front via emission and absorption of high-energy photons. This leads to a pre-acceleration of the fluid and pre-amplificaiton of the magnetic fields in the upstream region. Both have drastic implications on the shock structure. The model explains the persistence of the s...

  7. Why do patients drop out during radiation therapy?

    This study is to see how much proportion of the patients receiving radiation therapy drop out during radiation therapy and to analyze the reason for the incomplete treatment. The base population of this study was 1,100 patients with registration numbers 901 through 2,000 at Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea. Authors investigated the incidence of incomplete radiation therapy, which was defined as less than 95% of initially planned radiation dose, and the reasons for incomplete radiation therapy. One hundred and twenty eight patients (12%) did not complete the planned radiation therapy. The performance status of the incompletely treated patients was generally poorer than that of the base population, and the aim of radiation therapy was more commonly palliative. The most common reason for not completing the planned treatment was the patients' refusal of further radiation therapy because of the distrust of radiation therapy and/or the poor economic status. Careful case selection for radiation therapy with consideration of the socioeconomic status of the patients in addition to the clinical indication would be necessary for the reduction of incomplete treatment, especially in the palliative setting

  8. Assessment of secondary radiation and radiation protection in laser-driven proton therapy

    Faby, Sebastian; Wilkens, Jan J. [Technische Univ. Muenchen Klinikum rechts der Isar (Germany). Dept. of Radiation Oncology; Technische Univ. Muenchen (Germany). Physik-Dept.

    2015-09-01

    This work is a feasibility study of a radiation treatment unit with laser-driven protons based on a state-of-the-art energy selection system employing four dipole magnets in a compact shielded beamline. The secondary radiation emitted from the beamline and its energy selection system and the resulting effective dose to the patient are assessed. Further, it is evaluated whether or not such a compact system could be operated in a conventional treatment vault for clinical linear accelerators under the constraint of not exceeding the effective dose limit of 1 mSv per year to the general public outside the treatment room. The Monte Carlo code Geant4 is employed to simulate the secondary radiation generated while irradiating a hypothetical tumor. The secondary radiation inevitably generated inside the patient is taken into account as well, serving as a lower limit. The results show that the secondary radiation emanating from the shielded compact therapy system would pose a serious secondary dose contamination to the patient. This is due to the broad energy spectrum and in particular the angular distribution of the laser-driven protons, which make the investigated beamline together with the employed energy selection system quite inefficient. The secondary radiation also cannot be sufficiently absorbed in a conventional linear accelerator treatment vault to enable a clinical operation. A promising result, however, is the fact that the secondary radiation generated in the patient alone could be very well shielded by a regular treatment vault, allowing the application of more than 100 fractions of 2 Gy per day with protons. It is thus theoretically possible to treat patients with protons in such treatment vaults. Nevertheless, the results show that there is a clear need for alternative more efficient energy selection solutions for laser-driven protons.

  9. Assessment of secondary radiation and radiation protection in laser-driven proton therapy

    This work is a feasibility study of a radiation treatment unit with laser-driven protons based on a state-of-the-art energy selection system employing four dipole magnets in a compact shielded beamline. The secondary radiation emitted from the beamline and its energy selection system and the resulting effective dose to the patient are assessed. Further, it is evaluated whether or not such a compact system could be operated in a conventional treatment vault for clinical linear accelerators under the constraint of not exceeding the effective dose limit of 1 mSv per year to the general public outside the treatment room. The Monte Carlo code Geant4 is employed to simulate the secondary radiation generated while irradiating a hypothetical tumor. The secondary radiation inevitably generated inside the patient is taken into account as well, serving as a lower limit. The results show that the secondary radiation emanating from the shielded compact therapy system would pose a serious secondary dose contamination to the patient. This is due to the broad energy spectrum and in particular the angular distribution of the laser-driven protons, which make the investigated beamline together with the employed energy selection system quite inefficient. The secondary radiation also cannot be sufficiently absorbed in a conventional linear accelerator treatment vault to enable a clinical operation. A promising result, however, is the fact that the secondary radiation generated in the patient alone could be very well shielded by a regular treatment vault, allowing the application of more than 100 fractions of 2 Gy per day with protons. It is thus theoretically possible to treat patients with protons in such treatment vaults. Nevertheless, the results show that there is a clear need for alternative more efficient energy selection solutions for laser-driven protons.

  10. Impact of radiation therapy for benign diseases

    Radiation therapy of benign diseases represent a wide panel of indications. Some indications are clearly identified as treatment of arteriovenous malformations (AVM), hyperthyroid ophthalmopathy, postoperative heterotopic bone formations or keloid scars. Some indications are under evaluation as complications induced by neo-vessels of age-related macular degeneration or coronary restenosis after angioplasty. Some indications remain controversial with poor evidence of efficiency as treatment of bursitis, tendinitis or Dupuytren's disease. Some indications are now obsolete such as warts, or contra-indicated as treatment of infant and children. (authors)

  11. Mini-TEPCs for radiation therapy

    A mini-tissue-equivalent proportional-counter (TEPC) has been constructed to study the possibility to manufacture mini-counters without field-shaping tubes for radiation therapy. The mini-TEPC can be assembled with and without field-shaping tubes. It can be equipped with a mini-alpha source for a precise lineal energy calibration. After the positive conclusions of this study, a slim TEPC has been designed and constructed. The slim TEPC has an external diameter of only 2.7 mm. It has been tested with therapeutic proton beams and gamma ray sources. (authors)

  12. New irradiation geometry for microbeam radiation therapy

    Microbeam radiation therapy (MRT) has the potential to treat infantile brain tumours when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of x-rays but provides unusual resistance to radioneurotoxicity, presumably from the migration of endothelial cells from 'valleys' into 'peaks', i.e., into directly irradiated microslices of tissues. We present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumour area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumouricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumour in the paths of the arrays

  13. The preventation of radiation accidents in radiation therapy

    The radio-therapy planning system (RTPS) has improved the speed and accuracy of dose calculation and has come to be used in most hospitals in recent years. The RTPS calculated monitor unit (MU) defines the dose delivered to the patient. Radiation accidents caused by wrong MU calculated by erroneous basic data registration has frequently been reported in Japan. We investigated the MU calculated with the RTPS of this hospital. The measurement value resulted in the permissible error range set by the AAPM13 TG24 report. The basic data registered in the RTPS of this hospital and calculated MU were proven to be proper. (author)

  14. Emerging Canadian QA standards for radiation therapy

    Full text: Canada operates a publicly funded health care system in which 70% of health care costs are paid by some level of government. Radiotherapy, indeed most cancer management, falls within the publicly funded realm of Canada's health care system. National legislation (the Canada Health Act) guarantees access to cancer services for all Canadians. However, the financial responsibility for these services is borne by the provinces. Most Canadian provinces manage the cancer management problem through central cancer agencies. In the past few decades, these provincial cancer agencies have formed the Canadian Association of Provincial Cancer Agencies (CAPCA). This association has adopted a broad mandate for cancer management in Canada (see www.capca.ca). Included in this mandate is the adoption of standards and guidelines for all aspects of cancer control. The complexity of radiation therapy has long underscored the need for cooperation at the international and national levels in defining programmes and standards. In recent decades formal quality assurance programme recommendations have emerged in the United States, Europe and Great Britain. When defining quality assurance programs, Canadian radiation treatment centres have referenced U.S. and other program standards since they have been available. Recently, under the leadership of the Canadian Association of Provincial Cancer Agencies (CAPCA), Canadian national quality assurance program recommendations are emerging. A CAPCA sponsored project to harmonize Canadian quality assurance processes has resulted in a draft document entitled 'Standards for Quality Assurance at Canadian Radiation Treatment Centres'. This document provides recommendations for the broad framework of radiation therapy quality assurance programs. In addition, detailed work is currently underway regarding equipment quality control procedures. This paper explores the historical and political landscape in which the quality assurance problem has

  15. Involvement of Toll-like receptors in acute radiation syndrome and radiation therapy for cancer

    Toll-like receptors (TLR) are one of pattern recognition receptors that are indispensable for antibacterial and antiviral immunity. After TLRs sense pathogen-derived components, they activate intracellular signaling pathways, which results in the induction of proinflammatory cytokines. Although it is well known that radiation therapy is one of effective cancer therapies, radiation affects immune system. Recent evidences show the involvement of TLR in acute radiation syndrome and radiation therapy for cancer. I summarize to date knowledge on the involvement of Toll-like receptors in acute radiation syndromes and radiation therapy for cancer, and discuss the effects of ionizing radiation on TLR of innate immune cells. (author)

  16. Studying Radiation Damage in Structural Materials by Using Ion Accelerators

    Hosemann, Peter

    2011-02-01

    Radiation damage in structural materials is of major concern and a limiting factor for a wide range of engineering and scientific applications, including nuclear power production, medical applications, or components for scientific radiation sources. The usefulness of these applications is largely limited by the damage a material can sustain in the extreme environments of radiation, temperature, stress, and fatigue, over long periods of time. Although a wide range of materials has been extensively studied in nuclear reactors and neutron spallation sources since the beginning of the nuclear age, ion beam irradiations using particle accelerators are a more cost-effective alternative to study radiation damage in materials in a rather short period of time, allowing researchers to gain fundamental insights into the damage processes and to estimate the property changes due to irradiation. However, the comparison of results gained from ion beam irradiation, large-scale neutron irradiation, and a variety of experimental setups is not straightforward, and several effects have to be taken into account. It is the intention of this article to introduce the reader to the basic phenomena taking place and to point out the differences between classic reactor irradiations and ion irradiations. It will also provide an assessment of how accelerator-based ion beam irradiation is used today to gain insight into the damage in structural materials for large-scale engineering applications.

  17. Requirements for Simulating Space Radiation With Particle Accelerators

    Schimmerling, W.; Wilson, J. W.; Cucinotta, F.; Kim, M-H Y.

    2004-01-01

    Interplanetary space radiation consists of fully ionized nuclei of atomic elements with high energy for which only the few lowest energy ions can be stopped in shielding materials. The health risk from exposure to these ions and their secondary radiations generated in the materials of spacecraft and planetary surface enclosures is a major limiting factor in the management of space radiation risk. Accurate risk prediction depends on a knowledge of basic radiobiological mechanisms and how they are modified in the living tissues of a whole organism. To a large extent, this knowledge is not currently available. It is best developed at ground-based laboratories, using particle accelerator beams to simulate the components of space radiation. Different particles, in different energy regions, are required to study different biological effects, including beams of argon and iron nuclei in the energy range 600 to several thousand MeV/nucleon and carbon beams in the energy range of approximately 100 MeV/nucleon to approximately 1000 MeV/nucleon. Three facilities, one each in the United States, in Germany and in Japan, currently have the partial capability to satisfy these constraints. A facility has been proposed using the Brookhaven National Laboratory Booster Synchrotron in the United States; in conjunction with other on-site accelerators, it will be able to provide the full range of heavy ion beams and energies required. International cooperation in the use of these facilities is essential to the development of a safe international space program.

  18. Clinical applications of continuous infusion chemotherapy ahd concomitant radiation therapy

    This book presents information on the following topics: theoretical basis and clinical applications of 5-FU as a radiosensitizer; treatment of hepatic metastases from gastro intestingal primaries with split course radiation therapy; combined modality therapy with 5-FU, Mitomycin-C and radiation therapy for sqamous cell cancers; treatment of bladder carcinoma with concomitant infusion chemotherapy and irradiation; a treatment of invasiv bladder cancer by the XRT/5FU protocol; concomitant radiation therapy and doxorubicin by continuous infusion in advanced malignancies; cis platin by continuous infusion with concurrent radiation therapy in malignant tumors; combination of radiation with concomitant continuous adriamycin infusion in a patient with partially excised pleomorphic soft tissue sarcoma of the lower extremeity; treatment of recurrent carcinoma of the paranasal sinuses using concomitant infusion cis-platinum and radiation therapy; hepatic artery infusion for hepatic metastases in combination with hepatic resection and hepatic radiation; study of simultaneous radiation therapy, continuous infusion, 5FU and bolus mitomycin-C; cancer of the esophagus; continuous infusion VP-16, bolus cis-platinum and simultaneous radiation therapy as salvage therapy in small cell bronchogenic carcinoma; and concomitant radiation, mitomycin-C and 5-FU infusion in gastro intestinal cancer

  19. Neutron, Proton, and Photonuclear Cross Sections for Radiation Therapy and Radiation Protection

    The authors review recent work at Los Alamos to evaluate neutron, proton, and photonuclear cross section up to 150 MeV (to 250 MeV for protons), based on experimental data and nuclear model calculations. These data are represented in the ENDF format and can be used in computer codes to simulate radiation transport. They permit calculations of absorbed dose in the body from therapy beams, and through use of kerma coefficients allow absorbed dose to be estimated for a given neutron energy distribution. For radiation protection, these data can be used to determine shielding requirements in accelerator environments, and to calculate neutron, proton, gamma-ray, and radionuclide production. Illustrative comparisons of the evaluated cross section and kerma coefficient data with measurements are given

  20. Does concrete composition affect photoneutron production inside radiation therapy bunkers?

    Different types of concretes are used for bunker construction for radiation therapy. As neutron production occurs in high-energy photon beams, the purpose of this study was to investigate the effect of different concretes on photoneutron doses at an isocenter and maze entrance door. The 18-MV photon beam of a Varian 2100 C/D linear accelerator and a radiation therapy bunker were simulated using the MCNPX Monte Carlo code. Different commercially available concretes were used in photoneutron calculations for the simulated bunker. Higher neutron doses of the water phantom were seen for barytes and galena concretes, while there was no significant (less than 1%) difference between the neutron dose of the phantom for all other concretes. Also, the neutron fluence at the inner and outer maze entrance varied up to 36% depending on the concretes' atomic compositions. It can be concluded that application of high-density concretes in order to use limited space or for other purposes may cause higher neutron doses in the maze entrance door and consequently may impose stricter requirements for neutron shielding of maze entrance doors. (author)

  1. Particle acceleration, magnetization and radiation in relativistic shocks

    Derishev, Evgeny V.; Piran, Tsvi

    2016-08-01

    The mechanisms of particle acceleration and radiation, as well as magnetic field build-up and decay in relativistic collisionless shocks, are open questions with important implications to various phenomena in high-energy astrophysics. While the Weibel instability is possibly responsible for magnetic field build-up and diffusive shock acceleration is a model for acceleration, both have problems and current particle-in-cell simulations show that particles are accelerated only under special conditions and the magnetic field decays on a very short length-scale. We present here a novel model for the structure and the emission of highly relativistic collisionless shocks. The model takes into account (and is based on) non-local energy and momentum transport across the shock front via emission and absorption of high-energy photons. This leads to a pre-acceleration of the fluid and pre-amplification of the magnetic fields in the upstream region. Both have drastic implications on the shock structure. The model explains the persistence of the shock-generated magnetic field at large distances from the shock front. The dissipation of this magnetic field results in a continuous particle acceleration within the downstream region. A unique feature of the model is the existence of an `attractor', towards which any shock will evolve. The model is applicable to any relativistic shock, but its distinctive features show up only for sufficiently large compactness. We demonstrate that prompt and afterglow gamma-ray bursts' shocks satisfy the relevant conditions, and we compare their observations with the predictions of the model.

  2. Radiation Safety System for SPIDER Neutral Beam Accelerator

    Sandri, S.; Coniglio, A.; D'Arienzo, M.; Poggi, C.

    2011-12-01

    SPIDER (Source for Production of Ion of Deuterium Extracted from RF Plasma only) and MITICA (Megavolt ITER Injector Concept Advanced) are the ITER neutral beam injector (NBI) testing facilities of the PRIMA (Padova Research Injector Megavolt Accelerated) Center. Both injectors accelerate negative deuterium ions with a maximum energy of 1 MeV for MITICA and 100 keV for SPIDER with a maximum beam current of 40 A for both experiments. The SPIDER facility is classified in Italy as a particle accelerator. At present, the design of the radiation safety system for the facility has been completed and the relevant reports have been presented to the Italian regulatory authorities. Before SPIDER can operate, approval must be obtained from the Italian Regulatory Authority Board (IRAB) following a detailed licensing process. In the present work, the main project information and criteria for the SPIDER injector source are reported together with the analysis of hypothetical accidental situations and safety issues considerations. Neutron and photon nuclear analysis is presented, along with special shielding solutions designed to meet Italian regulatory dose limits. The contribution of activated corrosion products (ACP) to external exposure of workers has also been assessed. Nuclear analysis indicates that the photon contribution to worker external exposure is negligible, and the neutron dose can be considered by far the main radiation protection issue. Our results confirm that the injector has no important radiological impact on the population living around the facility.

  3. Radiation Safety System for SPIDER Neutral Beam Accelerator

    Sandri, S.; Poggi, C. [ENEA, Radiation Protection Institute, IRP-FUAC, Frascati (Italy); Coniglio, A. [Medical Physics Department, S. Giovanni Calibita Hospital, Fatebenefratelli, Isola Tiberina, Roma (Italy); D' Arienzo, M. [ENEA, Ionizing Radiation Metrology National Institute, METR, Casaccia, Rome (Italy)

    2011-12-13

    SPIDER (Source for Production of Ion of Deuterium Extracted from RF Plasma only) and MITICA (Megavolt ITER Injector Concept Advanced) are the ITER neutral beam injector (NBI) testing facilities of the PRIMA (Padova Research Injector Megavolt Accelerated) Center. Both injectors accelerate negative deuterium ions with a maximum energy of 1 MeV for MITICA and 100 keV for SPIDER with a maximum beam current of 40 A for both experiments. The SPIDER facility is classified in Italy as a particle accelerator. At present, the design of the radiation safety system for the facility has been completed and the relevant reports have been presented to the Italian regulatory authorities. Before SPIDER can operate, approval must be obtained from the Italian Regulatory Authority Board (IRAB) following a detailed licensing process. In the present work, the main project information and criteria for the SPIDER injector source are reported together with the analysis of hypothetical accidental situations and safety issues considerations. Neutron and photon nuclear analysis is presented, along with special shielding solutions designed to meet Italian regulatory dose limits. The contribution of activated corrosion products (ACP) to external exposure of workers has also been assessed. Nuclear analysis indicates that the photon contribution to worker external exposure is negligible, and the neutron dose can be considered by far the main radiation protection issue. Our results confirm that the injector has no important radiological impact on the population living around the facility.

  4. Radiation pressure acceleration: The factors limiting maximum attainable ion energy

    Bulanov, S. S.; Esarey, E.; Schroeder, C. B.; Bulanov, S. V.; Esirkepov, T. Zh.; Kando, M.; Pegoraro, F.; Leemans, W. P.

    2016-05-01

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it transparent for radiation and effectively terminating the acceleration. The off-normal incidence of the laser on the target, due either to the experimental setup, or to the deformation of the target, will also lead to establishing a limit on maximum ion energy.

  5. Radiation therapy of psoriasis and parapsoriasis

    Selective UV-Phototherapy with lambda 300-320 nm (SUP) as well as oral photochemotherapy with 8-methoxy-psoralen plus UVA-radiation (PUVA intern) are very effective in clearing the lesions of the generalized psoriasis and those of the chronic forms of parapsoriasis. Being treated with 4 suberythemal doses per week psoriasis patients are free or nearly free of symptoms after averagely 6.3 weeks of SUP-therapy or after 5.3 weeks of PUVA orally. The PUVA-therapy is mainly indicated in pustular, inverse and erythrodermic psoriasis as well as in parapsoriasis en plaques and variegata. In all other forms of psoriasis and in pityriasis lichenoides-chronica, we prefer the SUP-therapy because of less acute or chronic side effects, and because of its better practicability. X-rays are indicated in psoriais of nails, grenz-rays in superficial psoriatic lesions of the face, the armpits, the genitals and the anal region. (orig.)

  6. How Should I Care for Myself During Radiation Therapy?

    ... patients to be advocates. View more information How Should I Care for Myself During Radiation Therapy? Get ... decrease some of their treatment-related fatigue. You should ask your radiation oncologist what the best form ...

  7. Megavoltage radiation therapy: Meeting the technological needs

    The process of radiation therapy is complex and contains multiple steps, each of which has an impact on the quality of the treatment and on the possible clinical outcome. This treatment process includes diagnosis, patient immobilization, target and normal tissue localization, beam selection, beam shaping, dose calculation, technique optimization, simulation, prescription, treatment verification and, finally, the actual radiation treatment. Depending on the type of disease, it is not necessary that every patient undergo all the steps in the process; however, it is necessary that each step of the process used for a particular patient be carried out with the greatest accuracy. Inaccuracies at any stage of the process will be carried through to subsequent stages and have an impact on clinical outcome. It is therefore important to recognize, when addressing technological needs for megavoltage radiation treatment, that the radiation treatment machine technology should not be considered in isolation from the technologies associated with the other steps of the treatment process. In the purchase of radiation treatment equipment in any country, the following should be considered: (a) the availability and reliability of a country's physical infrastructure; (b) financial considerations; (c) the types and stages of disease most likely to be treated; (d) the number and types of professional staff available to apply the treatment technologies; (e) professional staff training and continuing education resources; (f) the number of patients requiring treatment with the treatment equipment available (i.e. the efficient use of available resources); (g) the treatment planning technologies (e.g. immobilization, imaging and the treatment planning computer) available to prepare the patient for the actual irradiation procedure; (h) the technological considerations of the therapy equipment in the context of the above factors (e.g. 60Co versus linac); (i) the cost of maintenance and local

  8. Laser-Driven Very High Energy Electron/Photon Beam Radiation Therapy in Conjunction with a Robotic System

    Kazuhisa Nakajima

    2014-12-01

    Full Text Available We present a new external-beam radiation therapy system using very-high-energy (VHE electron/photon beams generated by a centimeter-scale laser plasma accelerator built in a robotic system. Most types of external-beam radiation therapy are delivered using a machine called a medical linear accelerator driven by radio frequency (RF power amplifiers, producing electron beams with an energy range of 6–20 MeV, in conjunction with modern radiation therapy technologies for effective shaping of three-dimensional dose distributions and spatially accurate dose delivery with imaging verification. However, the limited penetration depth and low quality of the transverse penumbra at such electron beams delivered from the present RF linear accelerators prevent the implementation of advanced modalities in current cancer treatments. These drawbacks can be overcome if the electron energy is increased to above 50 MeV. To overcome the disadvantages of the present RF-based medical accelerators, harnessing recent advancement of laser-driven plasma accelerators capable of producing 1-GeV electron beams in a 1-cm gas cell, we propose a new embodiment of the external-beam radiation therapy robotic system delivering very high-energy electron/photon beams with an energy of 50–250 MeV; it is more compact, less expensive, and has a simpler operation and higher performance in comparison with the current radiation therapy system.

  9. Potential for heavy particle radiation therapy

    Radiation therapy remains one of the major forms of cancer treatment. When x rays are used in radiotherapy, there are large variations in radiation sensitivity among tumors because of the possible differences in the presence of hypoxic but viable tumor cells, differences in reoxygenation during treatment, differences in distribution of the tumor cells in their cell cycle, and differences in repair of sublethal damage. When high-LET particles are used, depending upon the LET distribution, these differences are reduced considerably. Because of these differences between x rays and high-LET particle effects, the high-LET particles may be more effective on tumor cells for a given effect on normal cells. Heavy particles have potential application in improving radiotherapy because of improved dose localization and possible advantages of high-LET particles due to their radiobiological characteristics. Protons, because of their defined range, Bragg peak, and small effects of scattering, have good dose localization characteristics. The use of protons in radiotherapy minimizes the morbidity of radiotherapy treatment and is very effective in treating deep tumors located near vital structures. Fast neutrons have no physical advantages over 60Co gamma rays but, because of their high-LET component, could be very effective in treating tumors that are resistant to conventional radiations. Negative pions and heavy ions combine some of the advantages of protons and fast neutrons

  10. Radiation therapy for carcinoma of the ear

    Carcinoma of the ear is rarely reported. From 1978 through 1992, we treated 9 patients, of whom 5 had malignant tumors of the external auditory canal and 4 had malignant tumors of the middle ear, with radiation. These patients accounted for only 0.9% of all patients with head and neck carcinomas treated with radiation at our hospital. Most patients had otorrhea and otalgia, but few patients had specific symptoms of carcinoma. The outcome in cases in which radiotherapy was given after tumor was completely resected was good. The overall 5-year survival rate was 55%. In addition, the 3-year survival rates in cases of carcinoma of the middle ear and of the external auditory canal were 50% and 60%. However, there was no statistical difference in 5-year survival rates between the two sites. We believe factors that affect prognosis are early diagnosis of malignant change, the area of tumor involvement at diagnosis, and combined therapy with surgery and radiation. (author)

  11. A gas-dynamical approach to radiation pressure acceleration

    Schmidt, Peter; Boine-Frankenheim, Oliver

    2016-06-01

    The study of high intensity ion beams driven by high power pulsed lasers is an active field of research. Of particular interest is the radiation pressure acceleration, for which simulations predict narrow band ion energies up to GeV. We derive a laser-piston model by applying techniques for non-relativistic gas-dynamics. The model reveals a laser intensity limit, below which sufficient laser-piston acceleration is impossible. The relation between target thickness and piston velocity as a function of the laser pulse length yields an approximation for the permissible target thickness. We performed one-dimensional Particle-In-Cell simulations to confirm the predictions of the analytical model. These simulations also reveal the importance of electromagnetic energy transport. We find that this energy transport limits the achievable compression and rarefies the plasma.

  12. Radiation Pressure Acceleration: the factors limiting maximum attainable ion energy

    Bulanov, S S; Schroeder, C B; Bulanov, S V; Esirkepov, T Zh; Kando, M; Pegoraro, F; Leemans, W P

    2016-01-01

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it trans...

  13. The application of a linear electron accelerator in radiation processing

    Ruiying, Zhou; Binglin, Wang; Wenxiu, Chen; Yongbao, Gu; Yinfen, Zhang; Simin, Qian; Andong, Liu; Peide, Wang

    A 3-5 MeV electron beam generated by a BF-5 type linear electron accelerator has been used in some radiation processing works, such as, (1) The cross-linking technology by radiation for the polyethylene foaming processing --- the correlation between the cross-linkage and the absorbed dose, the relation between the elongation of foaming polyethylene and the dose, the relation between the size of the cavities and the gelatin rate and the optimum range of dosage for foaming have been found. (2) The research work on the fast switch thyristor irradiated by electron beam --- The relation between the absorbed dose and the life-time of minority carriers has been studied and the optimum condition for radiation processing was determined. This process is much better than the conventional gold diffusion in raising the quality and end-product rate of these devices. Besides, we have made some testing works on the hereditary mutation of plant seeds and microorganism mutation induced by electron radiation and radiation sterilization for some medical instruments and foods.

  14. The use of electron accelerators for radiation disinfestation of grain

    One of the ways to fight the insect pest in grain is treatment by the beam of accelerated electrons. This method provides an immediate cessation of the reproduction of their lifetime and intensity of nutrition, as well as the elimination of the latent forms of grain infestation (eggs, larvae, etc.). The main advantages of the electron beam technology of grain disinfestation are the following: a possibility of grain disinfestation continuously at a rate corresponding to the high capacity of the process equipment of modern elevators with the full automation of the process and safety for personnel; it does not cause pollution of the environment and leaves no residual pollution in grain; the irradiated grain can be used immediately. At present, the powerful radiation disinfestation unit (Radiation Disinfestor, RD) on a base of ELV-4 40 kW power electron accelerator with 3 m length extraction device has been developed for a technological line of capacity of 400 t/h. In 1980 two RDs on a base of ELV-2 electron accelerator were put into operation at the Odessa port elevator of 200 t/h capacity each. RDs are installed between the elevator and the freight wharf of the port. The infested grain is delivered to the elevator for storage. The electron accelerators of the ELV-type used in this RD have an electron beam power of 20 kW at an energy of up to 1.5 MeV. The operation mode is continuous with a guaranteed operation time of no less than 5000 h per year. (author)

  15. Melanomas: radiobiology and role of radiation therapy

    Purpose/Objective: This course will review the radiobiology of malignant melanoma (MM) and the clinical use of radiation therapy for metastatic melanoma and selected primary sites. The course will emphasize the scientific principles underlying the clinical treatment of MM. Introduction: The incidence of malignant melanoma has one of the fastest growth rates in the world. In 1991, there were 32,000 cases and 7,000 deaths from MM in the United States. By the year 2000, one of every 90 Americans will develop MM. Wide local excision is the treatment of choice for Stage I-II cutaneous MM. Five-year survival rates depend on (a) sex: female-63%, male-40%; (b) tumor thickness: t 4 mm-25%; (c) location: extremity-60%, trunk-41%; and (d) regional lymph node status: negative-77%, positive-31%. Despite adequate surgery, 45-50% of all MM patients will develop metastatic disease. Radiobiology: Both the multi-target model: S = 1-(1-e-D/Do)n and the linear quadratic mode: -In(S) = alpha x D + beta x D2 predict a possible benefit for high dose per fraction (> 400 cGy) radiation therapy for some MM cell lines. The extrapolation number (n) varies from 1-100 for MM compared to other mammalian cells with n=2-4. The alpha/beta ratios for a variety of MM cell lines vary from 1 to 33. Other radiobiologic factors (repair of potentially lethal damage, hypoxia, reoxygenation, and repopulation) predict a wide variety of clinical responses to different time-dose prescriptions including high dose per fraction (> 400 cGy), low dose per fraction (200-300 cGy), or b.i.d. therapy. Based on a review of the radiobiology of MM, no single therapeutic strategy emerges which could be expected to be successful for all tumors. Time-Dose Prescriptions: A review of the retrospective and prospective clinical trials evaluating various time-dose prescriptions for MM reveals: (1) MM is a radiosensitive tumor over a wide range of diverse time-dose prescriptions; and (2) The high clinical response rates to a

  16. Radiation doses inside industrial irradiation installation with linear electron accelerator

    Lima, Alexandre R., E-mail: alexandre.lima@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Pelegrineli, Samuel Q.; Alo, Gabriel F., E-mail: samuelfisica@yahoo.com.br, E-mail: gabriel.alo@aceletron.com.br [Aceletron Irradiacao Industrial, Aceletrica Comercio e Representacoes Ltda, Rio de Janeiro, RJ (Brazil); Silva, Francisco C.A. Da, E-mail: dasilva@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Aceletron Industrial Irradiation Company is the unique installation in South America to provide industrial irradiation service using two linear electron accelerators of 18 kW and 10 MeV energy. The electron beam technology allows using electrons to irradiate many goods and materials, such as hospital and medical equipment, cosmetics, herbal products, polymers, peat, gemstones and food. Aceletron Company uses a concrete bunker with 3.66 m of thickness to provide the necessary occupational and environmental radiation protection of X-rays produced. The bunker is divided in main four areas: irradiation room, maze, tower and pit. Inside the irradiation room the x-rays radiation rates are measured in two ways: direct beam and 90 deg C. The rates produced in the conveyor system using 10 MeV energy are 500 Gy/min/mA and 15 Gy/min/mA, respectively. For a 1.8 mA current, the rates produced are 900 Gy/min and 27 Gy/min, respectively. Outside the bunker the radiation rate is at background level, but in the tower door and modulation room the radiation rate is 10 μSv/h. In 2014, during a routine operation, an effective dose of 30.90 mSv was recorded in a monthly individual dosimeter. After the investigation, it was concluded that the dose was only in the dosimeter because it felt inside the irradiation room. As Aceletron Company follows the principles of safety culture, it was decided to perform the radiation isodose curves, inside the four areas of the installation, to know exactly the hotspots positions, exposure times and radiation doses. Five hotspots were chosen taking into account worker's routes and possible operational places. The first experiment was done using a package with three TLD and OSLD dosimeters to obtain better statistical results. The first results for the five hotspots near the accelerator machine showed that the radiation dose rates were between 26 Gy/h and 31 Gy/h. The final measurements were performed using a package with one TLD and one OSLD

  17. Radiation reactions and injuries, their prophylaxis and therapy

    The most frequent local and total radiation reactions (epithema, dry and wet epidermitises, esophagitises, radiation variations of pulmonary tissues, the reaction of mucous membrane of the rectum, radiation cystitises) are described. The problems on delayed radiation injuries (delayed skin injuries, injuries of intestine, limbs, lungs, heart, organs of urochesia) are considered. Delayed radiation injuries are shown to be expected, if the tolerant level of healthy tissues irradiated increases during radiotherapy. Special attention is paid to prophylaxis and radiation injuries therapy

  18. Development of modulated electron beam for intensity modulated radiation therapy (IMRT) on a photocathode electron gun

    Radiation therapy of cancer is developing to un-uniform irradiation, for concentrating dose to a cancer tumor and reducing dose to normal tissue. As a step toward the Intensity modulated radiation therapy, we examined dynamic optical modulation of electron beam produced by a photocathode electron gun. Images on photo-masks were transferred onto a photocathode by relay imaging. Electron beam could be controlled by a remote mirror. Modulated electron beam maintained its shape on acceleration, had a fine spatial resolution, and could be moved dynamically by optical methods. As a second step, optical modulation of electron beam and dynamic control succeeded by a digital micro mirror device (DMD). (author)

  19. Crane RF accelerator for high current radiation damage studies

    An electron accelerator was designed and built for the Naval Weapons Support Center for transient radiation effects on electronics experiments and testing. The Crane L Band RF Electron Linac was designed to provide high currents over a wide range of pulse widths and energies. The energy extends to 60 MeV and pulse widths vary from a few ns to 10 μsec. Beam currents range from 20 amps in the short pulse case to 1.5 amps in the long pulse case. This paper describes the linac, its architecture, the e-gun and pulser, waveguides, klystrons and modulator, vacuum system, beam transport, and control systems. fig., tab

  20. How can we overcome tumor hypoxia in radiation therapy?

    Local recurrence and distant metastasis frequently occur after radiation therapy for cancer and can be fatal. Evidence obtained from radiochemical and radiobiological studies has revealed these problems to be caused, at least in part, by a tumor-specific microenvironment, hypoxia. Moreover, a transcription factor, hypoxia-inducible factor 1 (HIF-1), was identified as pivotal to hypoxia-mediated radioresistance. To overcome the problems, radiation oncologists have recently obtained powerful tools, such as 'simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT), which enables a booster dose of radiation to be delivered to small target fractions in a malignant tumor', 'hypoxia-selective cytotoxins/drugs', and 'HIF-1 inhibitors' etc. In order to fully exploit these innovative and interdisciplinary strategies in cancer therapy, it is critical to unveil the characteristics, intratumoral localization, and dynamics of hypoxia/HIF-1-active tumor cells during tumor growth and after radiation therapy. We have performed optical imaging experiments using tumor-bearing mice and revealed that the locations of HIF-1-active tumor cells changes dramatically as tumors grow. Moreover, HIF-1 activity changes markedly after radiation therapy. This review overviews fundamental problems surrounding tumor hypoxia in current radiation therapy, the function of HIF-1 in tumor radioresistance, the dynamics of hypoxic tumor cells during tumor growth and after radiation therapy, and how we should overcome the difficulties with radiation therapy using innovative interdisciplinary technologies. (author)

  1. Hypofractionated radiation therapy for the treatment of feline facial squamous cell carcinoma

    The efficacy of hypofractionated radiation protocol for feline facial squamous cell carcinoma was evaluated. Hypofractionated radiation therapy was applied to five cats showing single or multiple facial squamous cell carcinomas, in a total of ten histologically confirmed neoplastic lesions. Of the lesions, two were staged as T1, four as T2, two as T3, and two as T4. The animals were submitted to four radiation fractions from 7.6 to 10 grays each, with one week intervals. The equipment was a linear accelerator with electrons beam. The cats were evaluated weekly during the treatment and 30 and 60 days after the end of the radiation therapy. In this study, 40% of the lesions had complete remission, 40% partial remission, and 20% did not respond to the treatment. Response rates were lower as compared to other protocols previously used. However, hypofractionated radiation protocol was considered safe for feline facial squamous cell carcinoma. (author)

  2. Terahertz radiation source using an industrial electron linear accelerator

    Kalkal, Yashvir

    2015-01-01

    High power ($\\sim 100$ kW) industrial electron linear accelerators (linacs) are used for irradiation applications e.g., for pasteurization of food products, disinfection of medical waste, etc. We propose that high power electron beam from such an industrial linac can be first passed through an undulator to generate powerful terahertz (THz) radiation, and the spent electron beam coming out of the undulator can still be used for industrial applications. This will enhance the utilisation of a high power industrial linac. We have performed calculation of spontaneous emission in the undulator to show that for typical parameters, continuous terahertz radiation having power of the order of $\\mu$W can be produced, which may be useful for many scientific applications.

  3. Study on radiation sterilization of electron beam accelerator

    To study the effects of radiation sterilization of the electron beam, the three species of microorganisms, Escherichia. coli, Staphylococcus aureus and Proteus vulgaris were irradiated with the electron beam, delivered by the electron accelerator independently developed by the Institute of Modern Physics, Chinese Academy of Sciences, and the changes of superoxide dismutase (SOD) activity of these irradiated microorganisms were also tested. The results indicated that the Staphylococcus aureus were fully radio-sterilized with the radiation dosage of 2.0 kGy, but 2.2 kGy to the Escherichia. coli and Proteus vulgaris. Moreover, the data also demonstrated that the irradiation had noticeable effects on the SOD activity of the three microorganisms. (authors)

  4. Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy.

    Hess, Clayton B; Thompson, Holly M; Benedict, Stanley H; Seibert, J Anthony; Wong, Kenneth; Vaughan, Andrew T; Chen, Allen M

    2016-04-01

    Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning--a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of "gentle IGRT

  5. Sequential estrogen and radiation therapy for stage C prostate cancer

    Twenty of 34 stage C cases have been treated by sequential estrogen and radiation in our hospital between 1980 and 1989 and half of them had actually been done staging operation. An average age was 69.3. Tumor differentiations were distributed well in 5 cases, moderately in 5 and poorly in 9. The other unknown differentiation case was diagnosed by fine needle aspiration cytology. Previously administered estrogens were diethylstilbestrol diphosphate in 15 cases and others in 5. Total doses of 70 Gy in 35 fractions were sequentially delivered to the prostate, involving if necessary the seminal vesicles over a seven-week period by bilateral 120deg pendel using linear accelerator. Radiation field was sized from 6 x 6 to 8 x 8 cm. Estrogens have been continuously administered following radiation in 11 cases. Therapeutic effects upon the prostate were evaluated by digital rectal palpation. Improvement rate and atrophy rate of the primary lesion were 94.4% and 50% respectively. Recurrences were observed in 4 cases and 3 of them recurred within 3 years after initiation of the treatment. Recurred sites were in primary lesion in 2 cases and in bone in two. Five year non-recurrence rate was 81% by Kaplan Meier's method. One of 3 who discontinued hormone administration during or immediately after radiotherapy had local recurrence after 65 months and the other 2 cases died of gastric cancer and unknown cause. Causes of 6 dead cases were one prostate cancer, one gastric cancer, one heart failure, one pneumonia and 2 unknown. The cancer death rate was 25% (1/4 cases). Five year cumulative survival rate by Kaplan-Meier's method was 59.0%. Our results support the view that the sequential estrogen and radiation therapy for the pathological stage C patients of the prostate cancer may be as preferable as radiation alone for the treatment of stage B prostate cancer. (J.P.N.)

  6. Radiation therapy for carcinoma of the vulva

    Thirty-three patients suffering from squamous cell carcinoma of the vulva were treated with radiation therapy alone between 1961 and 1980 at the NIRS. The five-year survival rate and local control rate in each stage were 91 % and 36 % in T2 and 71 % and 64 % in T3, respectively. These results indicated that the early detection of recurrent tumor by close follow-up and an adequate retreatment procedure is very important for prologing survival. Late recurrence, more than five years after treatment, appeared in 30 % of the patients and this may be one of the special figures of postirradiated vulval carcinoma. The primary site was irradiated with external electron beams or radium needles, and better results were obtained with the later. Irradiation to the lymph node area in the pelvic cavity was necessary in patients with a more advanced stage of disease than T2. (author)

  7. Clinical results of radiation therapy for thymoma

    Masunaga, Shin-ichiro; Ono, Koji; Hiraoka, Masahiro; Sasai, Keisuke; Kitakabu, Yoshizumi; Abe, Mitsuyuki (Kyoto Univ. (Japan). Faculty of Medicine); Takahashi, Masaji; Tsutsui, Kazushige; Fushiki, Masato

    1992-05-01

    From August 1968 to December 1989, 58 patients with thymoma were treated by radiotherapy using cobalt-60 gamma ray. Eleven cases were treated by radiothrapy alone, 1 by preoperative radiotheapy, 43 by postoperative radiotherapy, and 3 in combination with intraoperative radiotherapy. The following points were clarified: (a) Postoperative and intraoperative radiotherapy were effective; (b) For postoperative radiotherapy, operability was the major factor influencing survival and local control, and Stage I and II tumors resected totally or subtotally as well as Stage III tumors resected totally were good indications for such therapy; (c) The patients with complicating myasthenia gravis had a longer survival time and better local control rate than those without it. Radiation pneumonitis was observed in 17 patients, and none of them died of this complication. In all cases in combination with intraoperative radiotherapy, dry desquamation was observed within the irradiated field. (author).

  8. Definition of treatment geometry in radiation therapy

    When accurate systems for quality assurance and treatment optimization are employed, a precise system for fixation and dosimetric and portal verification are as important as a continued and standardized code of practice for dosimetry and patient follow-up, including registration of tumour responses and acute and late normal tissue reactions. To improve the accuracy of existing dose response relations in order to improve future therapy the treatment geometry and dose delivery concepts have to be accurately defined and uniformly employed. A Nordic working group was set up in 1991 (by Nordic Association of Clinica Physics) to standardize the concepts and quantities used during the whole radiotherapy process in the Nordic countries. Now the group is finalizing its report ''Specification of Dose Delivery in Radiation Therapy''. The report emphasizes that the treatment geometry shall be consistent with the geometry used during the diagnostic work up. The patient fixation is of importance early in the diagnostic phase to ensure that the same reference points and patients position will be used both during the diagnostic work up, simulation and treatment execution. Reference Coordinate System of the patient is a concept based on defined anatomic reference points. This Patient Reference System is a local system which has validity for the tissues, organs and volumes defined during radiotherapy. The reference points of the Patient Reference System should in turn be used for beam set-up. The treatment geometry is then defined by using different concepts describing tissues which are mobile in the Patient Reference System, and finally, volumes which are fixed in this coordinate system. A Set-up Margin has to be considered for movements of the volumes defined in the Reference Coordinate System of the Patient in relation to the radiation beam. The Set-up Margin is dependent on the treatment technique and it is needed in the treatment planning procedure to ensure that the prescribed

  9. Radiation therapy for malignant lid tumor

    The case of a 42-year-old man with Meibomian gland carcinoma in his right lower lid is reported. The tumor found in the nasal part of the lower lid, was 12 mm x 13 mm in size. First, surgical resection was performed. The pathological diagnosis of the frozen section was 'undifferentiated basal cell epithelioma'. Second, cryotherapy was performed all over the cut surface. Later, the permanent section was pathologically diagnosed as 'undifferentiated Meibomian gland carcinoma'. Total 50 Gy irradiation therapy was therefore performed using a 9 Mev Linac electron beam, 25 x 20 mm field, with a lead protector for the cornea and lens. A lead contact lens did not afford good results because it was too easily shifted on the cornea, owing to its weight. Therefore, we made a racket-shaped lead protector. Fixed well with tape, this protector afforded good protective effect. Three years after treatment, the patient has good visual function, with no recurrence. This racket-shaped lead protector is thought to be useful in radiation therapy for malignant lid tumors. (author)

  10. Particle acceleration and radiation in Pulsar Wind Nebulae

    Amato, Elena

    2015-01-01

    Pulsar Wind Nebulae are the astrophysical sources that host the most relativistic shocks in Nature and the only Galactic sources in which we have direct evidence of PeV particles. These facts make them very interesting from the point of view of particle acceleration physics, and their proximity and brightness make them a place where fundamental processes common to different classes of relativistic sources have a better chance to be understood. I will discuss how well we understand the physics of Pulsar Wind Nebulae, describing recent progress and highlighting the main open questions. I will be mostly concerned with the subject of particle acceleration, but, as we will see, in order to clarify the physics of this process, it is important to determine the conditions of the plasma in the nebula. These in turn can only be constrained through detailed modelling of the PWN dynamics and radiation. The shock in the Crab Nebula is probably the most efficient accelerator known, both in terms of conversion of the flow e...

  11. Experimental Evidence for Particle Acceleration by Stimulated Emission of Radiation

    The interaction of electromagnetic radiation with free electrons in the presence of an active medium has several appealing outcomes. Among them the PASER scheme, standing for Particle Acceleration by Stimulated Emission of Radiation. In the framework of this scheme, energy stored in an active medium (microscopic cavities) is transferred directly to an e-beam traversing the medium, and therefore, accelerating the former. Recently, a proof-of-principle experiment of this concept was performed at the Brookhaven National Laboratory reaching a gain of 200keV in the kinetic energy of a 5ps, 0.1nc and 45MeV quasi-mono-energetic macro-bunch which is modulated by its interaction with a CO2 laser pulse in an adequate wiggler. In the framework of this proof-of-principle experiment both the fundamental frequency of the train of micro-bunches and the medium's resonance frequency (CO2 mixture) are matched. A good agreement is found between the energy gain and a 2D analytic model that has been developed

  12. Ultraviolet radiation therapy and UVR dose models

    Grimes, David Robert, E-mail: davidrobert.grimes@oncology.ox.ac.uk [School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland and Cancer Research UK/MRC Oxford Institute for Radiation Oncology, Gray Laboratory, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ (United Kingdom)

    2015-01-15

    Ultraviolet radiation (UVR) has been an effective treatment for a number of chronic skin disorders, and its ability to alleviate these conditions has been well documented. Although nonionizing, exposure to ultraviolet (UV) radiation is still damaging to deoxyribonucleic acid integrity, and has a number of unpleasant side effects ranging from erythema (sunburn) to carcinogenesis. As the conditions treated with this therapy tend to be chronic, exposures are repeated and can be high, increasing the lifetime probability of an adverse event or mutagenic effect. Despite the potential detrimental effects, quantitative ultraviolet dosimetry for phototherapy is an underdeveloped area and better dosimetry would allow clinicians to maximize biological effect whilst minimizing the repercussions of overexposure. This review gives a history and insight into the current state of UVR phototherapy, including an overview of biological effects of UVR, a discussion of UVR production, illness treated by this modality, cabin design and the clinical implementation of phototherapy, as well as clinical dose estimation techniques. Several dose models for ultraviolet phototherapy are also examined, and the need for an accurate computational dose estimation method in ultraviolet phototherapy is discussed.

  13. Liver cancer and selective internal radiation therapy

    Liver cancer is the biggest cancer-related killer of adults in the world. Liver cancer can be considered as two types: primary and secondary (metastatic). Selective Internal Radiation Therapy (SIRT) is a revolutionary treatment for advanced liver cancer that utilises new technologies designed to deliver radiation directly to the site of tumours. SIRT, on the other hand, involves the delivery of millions of microscopic radioactive spheres called SIR-Spheres directly to the site of the liver tumour/s, where they selectively irradiate the tumours. The anti-cancer effect is concentrated in the liver and there is little effect on cancer at other sites such as the lungs or bones. The SIR-Spheres are delivered through a catheter placed in the femoral artery of the upper thigh and threaded through the hepatic artery (the major blood vessel of the liver) to the site of the tumour. The microscopic spheres, each approximately 35 microns (the size of four red blood cells or one-third the diameter of a strand of hair), are bonded to yttrium-90 (Y-90), a pure beta emitter with a physical half-life of 64.1 hours (about 2.67 days). The microspheres are trapped in the tumour's vascular bed, where they destroy the tumour from inside. The average range of the radiation is only 2.5 mm, so it is wholly contained within the patient's body; after 14 days, only 2.5 percent of the radioactive activity remains. The microspheres are suspended in water for injection. The vials are shipped in lead shields for radiation protection. Treatment with SIR-Spheres is generally not regarded as a cure, but has been shown to shrink the cancer more than chemotherapy alone. This can increase life expectancy and improve quality of life. On occasion, patients treated with SIR-Spheres have had such marked shrinkage of the liver cancer that the cancer can be surgically removed at a later date. This has resulted in a long-term cure for some patients. SIRTeX Medical Limited has developed three separate cancer

  14. Diagnostic imaging and radiation therapy equipment

    This is the third edition of CSA Standard C22.2 No. 114 (now CAN/CSA-C22.2 No. 114), which is one of a series of standards issued by the Canadian Standards Association under Part II of the Canadian Electrical Code. This edition marks an important shift towards harmonization of Canadian requirements with those of the European community and the United States. Also important to this edition is the expansion of its scope to include the complete range of diagnostic imaging and radiation therapy equipment, rather than solely radiation-emitting equipment. In so doing, equipment previously addressed by CSA Standard C22.2 No. 125, Electromedical Equipment, specifically lasers for medical applications and diagnostic ultrasound units, is now dealt with in the new edition. By virtue of this expanded scope, many of the technical requirements in the electromedical equipment standard have been introduced to the new edition, thereby bringing CSA Standard C22.2 No. 114 up to date. 14 tabs., 16 figs

  15. Interfraction changes in the brain during radiation therapy

    Our study population consisted of 63 patients with brain tumours treated using image-guided radiation therapy(IGRT). Cranial IGRT corrections were expected to be small, it was found that interfraction changes occurred in a sizable proportion of these radiation therapy patients. Such changes affect clinical target volume coverage and critical structure avoidance. (author)

  16. 21 CFR 892.5840 - Radiation therapy simulation system.

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy simulation system. 892.5840 Section 892.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5840 Radiation therapy...

  17. Neoadjuvant chemotherapy and radiation therapy compared with radiation therapy alone in advanced nasopharyngeal carcinoma

    Purpose: To analyze the impact of neoadjuvant chemotherapy on the treatment of locoregionally advanced nasopharyngeal carcinoma and to assess the outcomes of patients receiving such treatment. Methods and Materials: We analyzed 137 previously untreated and histologically confirmed advanced stage nasopharyngeal carcinoma patients treated with either radiation therapy only or combined radiation therapy and chemotherapy at the Seoul National University Hospital between 1984 and 1996. The stage distribution was as follows: AJCC Stage III-21, Stage IV-61 in the radiation therapy group (RT group); AJCC Stage III-1, Stage IV-54 in neoadjuvant chemotherapy and radiation therapy group (CT/RT group). The median follow-up for surviving patients was 48 months. Results: The 5-year overall survival (OS) rates were 71% for the CT/RT group and 59% for the RT group (p = 0.04). The 5-year actuarial disease-free survival (DFS) rates were 63% for the CT/RT group and 52% for the RT group (p = 0.04). Distant metastasis (DM) incidence was significantly lower in the CT/RT group. The 5-year freedom from distant metastasis rates were 84% for the CT/RT group and 66% for the RT group (p 0.01). The incidence of locoregional failures was also lower in the CT/RT group, although this difference did not reach statistical significance (69% vs. 56%, p = 0.09) Conclusion: While not providing conclusive evidence, historical evidence from this institution suggests that neoadjuvant chemotherapy significantly improves both overall and the disease-free survival of patients with advanced stage nasopharyngeal carcinoma

  18. Electron string ion sources for carbon ion cancer therapy accelerators

    Boytsov, A Yu; Donets, E D; Donets, E E; Katagiri, K; Noda, K; Ponkin, D O; Ramzdorf, A Yu; Salnikov, V V; Shutov, V B

    2015-01-01

    The Electron String type of Ion Sources (ESIS) was developed, constructed and tested first in the Joint Institute for Nuclear Research. These ion sources can be the appropriate sources for production of pulsed C4+ and C6+ ion beams which can be used for cancer therapy accelerators. In fact the test ESIS Krion-6T already now at the solenoid magnetic field only 4.6 T provides more than 10^10 C4+ ions per pulse and about 5*10^9 C6+ ions per pulse. Such ion sources could be suitable for application at synchrotrons. It was also found, that Krion-6T can provide more than 10^11 C6+ ions per second at 100 Hz repetition rate, and the repetition rate can be increased at the same or larger ion output per second. This makes ESIS applicable at cyclotrons as well. As for production of 11C radioactive ion beams ESIS can be the most economic kind of ion source. To proof that the special cryogenic cell for pulse injection of gaseous species into electron string was successfully tested using the ESIS Krion-2M.

  19. Radiation therapy - what to ask your doctor

    ... Lung cancer - small cell Metastatic brain tumor Non-Hodgkin lymphoma Prostate cancer Testicular cancer Patient Instructions Abdominal radiation - discharge Bleeding during cancer treatment Brain radiation - discharge Breast radiation - discharge Chest radiation - ...

  20. Radiation therapy and photodynamic therapy for biliary tract and ampullary carcinomas

    Saito, Hiroya; Takada, Tadahiro; Miyazaki, Masaru; Miyakawa, Shuichi; Tsukada, Kazuhiro; Nagino, Masato; Kondo, Satoshi; Furuse, Junji; Tsuyuguchi, Toshio; Kimura, Fumio; Yoshitomi, Hideyuki; Nozawa, Satoshi; YOSHIDA, Masahiro; Wada, Keita; Amano, Hodaka

    2008-01-01

    The purpose of radiation therapy for unresectable biliary tract cancer is to prolong survival or prolong stent patency, and to provide palliation of pain. For unresectable bile duct cancer, there are a number of studies showing that radiation therapy is superior to the best supportive care. Although radiation therapy is used in many institutions, no large randomized controlled trials (RCTs) have been performed to date and the evidence level supporting the superiority of this treatment is low....

  1. Radiation pneumonitis after stereotactic radiation therapy for lung cancer

    Hideomi; Yamashita; Wataru; Takahashi; Akihiro; Haga; Keiichi; Nakagawa

    2014-01-01

    Stereotactic body radiation therapy(SBRT)has a locacontrol rate of 95%at 2 years for non-small cell lungcancer(NSCLC)and should improve the prognosis oinoperable patients,elderly patients,and patients withsignificant comorbidities who have early-stage NSCLCThe safety of SBRT is being confirmed in internationalmulti-institutional PhaseⅡtrials for peripheral lungcancer in both inoperable and operable patients,bureports so far have found that SBRT is a safe and effective treatment for early-stage NSCLC and early metastatic lung cancer.Radiation pneumonitis(RP)is oneof the most common toxicities of SBRT.Although mospost-treatment RP is Grade 1 or 2 and either asymptomatic or manageable,a few cases are severe,symptomatic,and there is a risk for mortality.The reportedrates of symptomatic RP after SBRT range from 9%to28%.Being able to predict the risk of RP after SBRT isextremely useful in treatment planning.A dose-effecrelationship has been demonstrated,but suggesteddose-volume factors like mean lung dose,lung V20and/or lung V2.5 differed among the reports.We foundthat patients who present with an interstitial pneumo-nitis shadow on computed tomography scan and high levels of serum Krebs von den Lungen-6 and surfactant protein D have a high rate of severe radiation pneumo-nitis after SBRT.At our institution,lung cancer patients with these risk factors have not received SBRT since 2006,and our rate of severe RP after SBRT has de-creased significantly since then.

  2. The implementation of a therapy radiation dose measurement system using a microcomputer

    Lee, Dong Hun; Chai, Jong Seo; Kim, Yu Seok; Hong, Seong Seok; Lee, Min Yong [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    In this paper, the therapy radiation dose measurement system has been implemented by using a microcomputer after radiation was irradiated on diodes from the MM22 microtron accelerator. We have displayed 7-channel diode output values on the LCD after processing those in the 80196 MCU (Micro Computer Unit). Signal processing has been performed in the pulse mode because we can process the signal fast and use it to perform portal image by increasing a number of diode channels in the future. In order to verify the microcomputer based radiation measurement system of diodes, diode output values were compared with that of semiconductor. (author). 6 refs., 11 figs.

  3. The implementation of a therapy radiation dose measurement system using a microcomputer

    In this paper, the therapy radiation dose measurement system has been implemented by using a microcomputer after radiation was irradiated on diodes from the MM22 microtron accelerator. We have displayed 7-channel diode output values on the LCD after processing those in the 80196 MCU (Micro Computer Unit). Signal processing has been performed in the pulse mode because we can process the signal fast and use it to perform portal image by increasing a number of diode channels in the future. In order to verify the microcomputer based radiation measurement system of diodes, diode output values were compared with that of semiconductor. (author). 6 refs., 11 figs

  4. Radiation therapy among atomic bomb survivors, Hiroshima and Nagasaki

    In the continuing evaluations of atomic bomb survivors for late radiation effects, not only doses from the A-bombs but those from other radiation sources must be considered, for the latter may be concomitantly acting factors causing bias among these investigations. In the present study, among 73 Hiroshima and 22 Nagasaki Adult Health Study (AHS) subjects who reported receiving radiation therapy, from 1970 through 1979, the medical records of 72 and 20, respectively, were reviewed, and 41 Hiroshima and 14 Nagasaki subjects were confirmed to have received radiation therapy. The data obtained in the present study were pooled with those of the previous investigation on radiation therapy exposures of AHS subjects prior to 1970. A total of 190 subjects have been documented as receiving radiation therapy and their doses were estimated. Energies used in treatments and diseases treated are discussed. Malignancies developed subsequent to radiation therapy in seven cases; five after treatment for malignancies and two after treatment for benign diseases. Neoplasms of 12 AHS subjects may have been induced by earlier radiation therapy; 5 in the earlier study and 7 in the present one. These investigations underscore the need for continued documentation of exposures to ionizing radiation for medical reasons, especially from sources incurring relatively high doses. Bias in assessments of late radiation effects among A-bomb survivors can thus be avoided. (author)

  5. Cobalt, Linac, or Other: What Is the Best Solution for Radiation Therapy in Developing Countries?

    Page, Brandi R., E-mail: bpage@wakehealth.edu [Wake Forest University Baptist Medical Center, Winston-Salem, North Carolina (United States); Hudson, Alana D.; Brown, Derek W. [Tom Baker Cancer Centre, University of Calgary, Calgary (Canada); Shulman, Adam C. [Overlook Medical Center, Summit, New Jersey (United States); Abdel-Wahab, May [Cleveland Clinic and Cleveland Clinic Lerner School of Medicine, Cleveland, Ohio (United States); Fisher, Brandon J. [Gamma West Cancer Services, Layton, Utah (United States); Radiating Hope, Midvale, Utah (www.radiatinghope.org) (United States); Patel, Shilpen [University of Washington, Seattle, Washington (United States)

    2014-07-01

    The international growth of cancer and lack of available treatment is en route to become a global crisis. With >60% of cancer patients needing radiation therapy at some point during their treatment course, the lack of available facilities and treatment programs worldwide is extremely problematic. The number of deaths from treatable cancers is projected to increase to 11.5 million deaths in 2030 because the international population is aging and growing. In this review, we present how best to answer the need for radiation therapy facilities from a technical standpoint. Specifically, we examine whether cobalt teletherapy machines or megavoltage linear accelerator machines are best equipped to handle the multitudes in need of radiation therapy treatment in the developing world.

  6. Cobalt, Linac, or Other: What Is the Best Solution for Radiation Therapy in Developing Countries?

    The international growth of cancer and lack of available treatment is en route to become a global crisis. With >60% of cancer patients needing radiation therapy at some point during their treatment course, the lack of available facilities and treatment programs worldwide is extremely problematic. The number of deaths from treatable cancers is projected to increase to 11.5 million deaths in 2030 because the international population is aging and growing. In this review, we present how best to answer the need for radiation therapy facilities from a technical standpoint. Specifically, we examine whether cobalt teletherapy machines or megavoltage linear accelerator machines are best equipped to handle the multitudes in need of radiation therapy treatment in the developing world

  7. Radiation from an accelerating neutral body: The case of rotation

    Yarman, Tolga; Arik, Metin; Kholmetskii, Alexander L.

    2013-11-01

    When an object is bound at rest to an attractional field, its rest mass (owing to the law of energy conservation, including the mass and energy equivalence of the Special Theory of Relativity) must decrease. The mass deficiency coming into play indicates a corresponding rest energy discharge. Thus, bringing an object to a rotational motion means that the energy transferred for this purpose serves to extract just as much rest mass (or similarly "rest energy", were the speed of light in empty space taken to be unity) out of it. Here, it is shown that during angular acceleration, photons of fundamental energy are emitted, while the object is kept on being delivered to a more and more intense rotational accelerational field, being the instantaneous angular velocity of the rotating object. This fundamental energy, as seen, does not depend on anything else (such as the mass or charge of the object), and it is in harmony with Bohr's Principle of Correspondence. This means at the same time, that emission will be achieved, as long as the angular velocity keeps on increasing, and will cease right after the object reaches a stationary rotational motion (a constant centrifugal acceleration), but if the object were brought to rotation in vacuum with no friction. By the same token, one can affirm that even the rotation at a macroscopic level is quantized, and can only take on "given angular velocities" (which can only be increased, bit by bit). The rate of emission of photons of concern is, on the other hand, proportional to the angular acceleration of the object, similarly to the derivative of the tangential acceleration with respect to time. It is thus constant for a "constant angular acceleration", although the energy of the emitted photons will increase with increasing , until the rotation reaches a stationary level, after which we expect no emission --let us stress-- if the object is in rotation in vacuum, along with no whatsoever friction (such as the case of a rotating

  8. Medical accelerator project for proton and carbon therapy in Hyogo Prefectural Government

    Hyogo Prefectural Government starts building a facility for proton radiation therapy that will also provide carbon therapy. The facility will be completed in 2000. Its output energy can be charged to 230 MeV/u proton beam and to 320 MeV/u carbon beam. In 1995, fundamental design of an accelerator was ordered. In the present plan, five rooms are to be provided for medical treatment. Different beam lines will be equipped in each room, one horizontal, one vertical with horizontal, two gantries, and one 45-degree oblique beam. 50-bed hospital will be built on an adjacent site to accommodate up to more than one thousand patients a year. These medical facilities will be part of the Harima Science Garden City, where Super Photon ring-8 GeV synchrotron radiation facility (SPring-8) is now building, which will be one of the most powerful synchrotron facilities in the world when completed in 1997. In the future, the medical imaging of using the beam of SPring-8 will be possible to diagnose the early cancer, which will be treated by proton or carbon beams without surgery. (author)

  9. Optimal approach in early breast cancer: Radiation therapy

    Poortmans, Philip

    2013-01-01

    Radiation therapy significantly reduces by at least 70% the relative risk of local and regional recurrences for breast cancer after surgery. A positive influence on overall survival has been clearly demonstrated, especially for patients with a high absolute risk for locoregional recurrences. However, this is partially counterbalanced by late toxicity (dependent upon the radiation dose) especially to cardiac structures. Apart from this toxicity, a clear influence of radiation-therapy-related f...

  10. Intensity-modulated radiation therapy: emerging cancer treatment technology

    T.S. Hong; Ritter, M. A.; Tomé, W. A.; Harari, P.M.

    2005-01-01

    The use of intensity-modulated radiation therapy (IMRT) is rapidly advancing in the field of radiation oncology. Intensity-modulated radiation therapy allows for improved dose conformality, thereby affording the potential to decrease the spectrum of normal tissue toxicities associated with IMRT. Preliminary results with IMRT are quite promising; however, the clinical data is relatively immature and overall patient numbers remain small. High-quality IMRT requires intensive physics support and ...

  11. Dosimetry in radiation fields around high-energy proton accelerators

    Agosteo, S; Silari, M; Theis, C

    2008-01-01

    Radiation dosimetry at high-energy proton accelerators is a difficult task because of the complexity of the stray radiation field. A good knowledge of this mixed radiation field is very important to be able to select the type of detectors (active and/or passive) to be employed for routine area monitoring and to choose the personal dosimeter legally required for estimating the effective dose received by individuals. At the same time, the response function of the detectors to the mixed field must be thoroughly understood. A proper calibration of a device, which may involve a complex series of measurements in various reference fields, is needed. Monte Carlo simulations provide a complementary – and sometimes the principal – mean of determining the response function. The ambient dose equivalent rates during operation range from a few hundreds of μSv per year to a few mSv per year. To measure such rates one needs detectors of high sensitivity and/or capable of integrating over long periods. The main challenge...

  12. Whole-brain hippocampal sparing radiation therapy: Volume-modulated arc therapy vs intensity-modulated radiation therapy case study.

    Lee, Katrina; Lenards, Nishele; Holson, Janice

    2016-01-01

    The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient׳s neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient׳s data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain. PMID:26235550

  13. Particle selection for laser-accelerated proton therapy feasibility study

    In this paper we present calculations for the design of a particle selection system for laser-accelerated proton therapy. Laser-accelerated protons coming from a thin high-density foil have broad energy and angular spectra leading to dose distributions that cannot be directly used for therapeutic applications. Our solution to this problem is a compact particle selection and collimation device that delivers small pencil beams of protons with desired energy spectra. We propose a spectrometer-like particle selection and beam modulation system in which the magnetic field will be used to spread the protons spatially according to their energies and emitting angles. Subsequently, an aperture will be used to select the protons within a therapeutic window of energy (energy modulation). It will be shown that for the effective proton spatial differentiation, the primary collimation device should be used, which will collimate protons to the desired angular distribution and limit the spatial mixing of different energy protons once they have traveled through the magnetic system. Due to the angular proton distribution, the spatial mixing of protons of different energies will always be present and it will result in a proton energy spread with the width depending on the energy. For 250 MeV protons, the width (from the maximum to the minimum energy) is found to be 50 MeV for the magnetic field configuration used in our calculations. As the proton energy decreases, its energy width decreases as well, and for 80 MeV protons it equals 9 MeV. The presence of the energy width in the proton energy distribution will modify the depth dose curves needed for the energy modulation calculation. The matching magnetic field setup will ensure the refocusing of the selected protons and the final beam will be collimated by the secondary collimator. The calculations presented in this article show that the dose rate that the selection system can yield is on the order of D=260 Gy/min for a field size

  14. Radiation-induced lung injury outside the irradiated area after radiation therapy for breast cancer

    Organizing pneumonia (OP) and eosinophilic pneumonia (EP) are known as lung injuries after radiation therapy for breast cancer. In this study, we reported nine cases of OP and a case of EP after radiation therapy. All 10 women (62±10 years of age) were nonsmokers. Nine patients received endocrine therapy after radiation therapy. The mean intervals from completion of radiation therapy to occurrence of any symptoms were 119 days. All the patients have symptoms, but none are severe. Seven patients were treated with corticosteroids, and three were without treatment. All patients improved, but a relapse occurred in three (two treated with corticosteroid, one without treatment). Because of our findings and the previous studies, tobacco smoke may have played a suppressive role in the occurrence of lung injury in nonirradiated areas after radiation therapy in breast cancer patients, and endocrine therapy may have played a promotive role. (author)

  15. Polymer gel dosimetry system for radiation therapy

    Purpose/Objective: Recently developed treatment modalities such as stereotactic and conformal radiation therapy produce complex dose distributions which are difficult or impractical to measure with conventional dosimetry instrumentation. Three-dimensional treatment planning systems which purport to calculate these complex dose distributions should be compared to experimental results before being routinely applied to clinical problems. There is a need for a new class of tissue-equivalent dosimeters capable of providing accurate, high resolution, time-integrated and three dimensional dose distributions. The recently developed BANG polymer gel dosimetry system (MGS Research, Inc., Guilford, CT) is ideally suited for the task described above. Physico-chemical principles of the polymer gel dosimetry are presented, together with examples of its application to radiation therapy. Data analysis and display program, written for Macintosh computer, is demonstrated. Materials and Methods: Radiation-induced polymerization of acrylic monomers, which are dispersed in tissue-equivalent gelatin, has been shown to be dependent on the dose, but independent of the dose rate or photon energy. Therefore, the spatial distribution of polymer in the gel is precisely representative of the dose distribution. As the polymeric microparticles reduce the water proton NMR relaxation times in the gel, the dose distribution can be measured with high resolution and accuracy using magnetic resonance imaging. Also, as these microparticles cannot diffuse through the gelatin matrix, their distribution is permanent. An improved formulation of the BANG dosimeter consists of 3% w/v acrylic acid, 3% N,N'-methylene-bis-acrylamide, 1% sodium hydroxide, 5% gelatin, and 88% water. MR images are transferred via a local network to a Macintosh computer, and R2 maps constructed on the basis of multiple TE images, using a non-linear least squares fit based on the Levenberg-Marquardt algorithm. A dose-to-R2

  16. Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density

    Bake, Muhammad Ali; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hong Xueren [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

    2012-08-15

    The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

  17. Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density

    The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

  18. Recurrent spontaneous pneumothorax after radiation therapy to the thorax

    Twiford, T.W. Jr.; Zornoza, J.; Libshitz, H.I.

    1978-03-01

    Two patients who received radiation therapy to the thorax and who developed recurrent spontaneous pneumothoraces are presented. Patients with recurrent pneumothoraces secondary to radiation have not been described previously. Pleural changes secondary to radiation may contribute significantly to the complicated clinical course of these patients.

  19. Localized fibrous mesothelioma of pleura following external ionizing radiation therapy

    Bilbey, J.H.; Mueller, N.L.M.; Miller, R.R.; Nelems, B.

    1988-12-01

    Carcinogenesis is a well-known complication of radiation exposure. Ionizing radiation also leads to an increased incidence of benign tumors. A 36-year-old woman had a localized fibrous mesothelioma of the pleura and an ipsilateral breast carcinoma 23 years after receiving external radiation therapy for treatment of a chest wall keloid.

  20. Radiation Therapy for Chloroma (Granulocytic Sarcoma)

    Bakst, Richard; Wolden, Suzanne [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yahalom, Joachim, E-mail: yahalomj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-04-01

    Objectives: Chloroma (granulocytic sarcoma) is a rare, extramedullary tumor of immature myeloid cells related to acute nonlymphocytic leukemia or myelodysplastic syndrome. Radiation therapy (RT) is often used in the treatment of chloromas; however, modern studies of RT are lacking. We reviewed our experience to analyze treatment response, disease control, and toxicity associated with RT to develop treatment algorithm recommendations for patients with chloroma. Patients and Methods: Thirty-eight patients who underwent treatment for chloromas at our institution between February 1990 and June 2010 were identified and their medical records were reviewed and analyzed. Results: The majority of patients that presented with chloroma at the time of initial leukemia diagnosis (78%) have not received RT because it regressed after initial chemotherapy. Yet most patients that relapsed or remained with chloroma after chemotherapy are in the RT cohort (90%). Thirty-three courses of RT were administered to 22 patients. Radiation subsite breakdown was: 39% head and neck, 24% extremity, 9% spine, 9% brain, 6% genitourinary, 6% breast, 3% pelvis, and 3% genitourinary. Median dose was 20 (6-36) Gy. Kaplan-Meier estimates of progression-free survival and overall survival in the RT cohort were 39% and 43%, respectively, at 5 years. At a median follow-up of 11 months since RT, only 1 patient developed progressive disease at the irradiated site and 4 patients developed chloromas at other sites. RT was well tolerated without significant acute or late effects and provided symptom relief in 95% of cases. Conclusions: The majority of patients with chloromas were referred for RT when there was extramedullary progression, marrow relapse, or rapid symptom relief required. RT resulted in excellent local disease control and palliation of symptoms without significant toxicity. We recommend irradiating chloromas to at least 20 Gy, and propose 24 Gy in 12 fractions as an appropriate regimen.

  1. Beryllium Target for Accelerator - Based Boron Neutron Capture Therapy

    This work is part of a project for developing Accelerator Based Boron Neutron Capture Therapy (AB- BNCT) for which the generation of neutrons through nuclear reactions like 9Be(d,n) is necessary. In this paper first results of the design and development of such neutron production targets are presented. For this purpose, the neutron production target has to be able to withstand the mechanical and thermal stresses produced by intense beams of deuterons (of 1.4 MeV with a total current of about 30mA). In particular, the target should be able to dissipate an energy density of up to 1 kW/cm2 and preserve its physical and mechanical properties for a sufficient length of time under irradiation conditions and hydrogen damage. The target is proposed to consist of a thin Be deposit (neutron producing material) on a thin W or Mo layer to stop the beam and a Cu backing to help carry away the heat load. To achieve the adhesion of the Be films on W, Mo and Cu substrates, a powder blasting technique was applied with quartz and alumina microspheres. On the other hand, Ag deposits were made on some of the substrates previously blasted to favor the chemical affinity between Beryllium and the substrate thus improving adhesion. Be deposits were characterized by means of different techniques including Electron Microscopy (Sem) and Xr Diffraction. Roughness and thickness measurements were also made. To satisfy the power dissipation requirements for the neutron production target, a microchannel system model is proposed. The simulation based on this model permits to determine the geometric parameters of the prototype complying with the requirements of a microchannel system. Results were compared with those in several publications and discrepancies lower than 10% were found in all cases. A prototype for model validation is designed here for which simulations of fluid and structural mechanics were carried out and discussed

  2. Intensity Modulated Radiation Therapy. Development of the technique

    Full text: Introduction: Intensity Modulated Radiation Therapy (IMRT) is a result of advances in computer sciences that allowed the development of new technology related to planning and radiation therapy. IMRT was developed to homogenize the dose in the target volumes and decrease the dose in the surrounding healthy tissue. Using a software with high calculation capacity a simultaneous irradiation with different doses in a given volume is achieved. IMRT is based on internal planning. Material and methods: 628 patients were treated with IMRT in prostate lesions, head and neck, breast, thorax, abdomen and brain since August 2008. The software for IMRT is the XIO CMS and the accelerator used is a Varian Clinac 6 / 100. IMRT requires a first simulation, where immobilization systems are selected (mats, thermoplastic masks, among others) and the demarcation of the target structures, healthy tissue and dose prescription by a tattoo. Images of CT / MRI are merged when necessary. Once the system made the treatment optimization, this one is regulated by modulators. These are produced by numerical control machines from digital files produced by software. In a second modulation the planned irradiation is checked and tattoo is carried out according with this. We have a strict process of quality assurance to assess the viability of the plan before its implementation. We use the Map Check it possible to compare the dose on the central axis and the distribution in the whole plane regarding to that generated by the planning system. From 03/2008 the virtual simulation process was implemented integrating the described stages. Results and Conclusions: IMRT is a complex technique. The meticulous planning, implementation of process and quality control allows the use of this technique in a reliable and secure way. With IMRT we achieved a high level of dose conformation, less irradiation of healthy tissue, lower rates of complications and the dose escalation for some tumors. (authors)

  3. 160 MeV laser-accelerated protons from CH2 nano-targets for proton cancer therapy

    Hegelich, B M; Albright, B J; Cheung, M; Dromey, B; Gautier, D C; Hamilton, C; Letzring, S; Munchhausen, R; Palaniyappan, S; Shah, R; Wu, H -C; Yin, L; Fernández, J C

    2013-01-01

    Proton (and ion) cancer therapy has proven to be an extremely effective even supe-rior method of treatment for some tumors 1-4. A major problem, however, lies in the cost of the particle accelerator facilities; high procurement costs severely limit the availability of ion radiation therapy, with only ~26 centers worldwide. Moreover, high operating costs often prevent economic operation without state subsidies and have led to a shutdown of existing facilities 5,6. Laser-accelerated proton and ion beams have long been thought of as a way out of this dilemma, with the potential to provide the required ion beams at lower cost and smaller facility footprint 7-14. The biggest challenge has been the achievement of sufficient particle energy for therapy, in the 150-250 MeV range for protons 15,16. For the last decade, the maximum exper-imentally observed energy of laser-accelerated protons has remained at ~60 MeV 17. Here we the experimental demonstration of laser-accelerated protons to energies exceeding 150 MeV, re...

  4. Particle acceleration by stimulated emission of radiation in cylindrical waveguide

    TIAN Xiu-Fang; WU Cong-Feng; JIA Qi-Ka

    2015-01-01

    In particle acceleration by stimulated emission of radiation (PASER),efficient interaction occurs when a train of micro-bunches has periodicity identical to the resonance frequency of the medium.Previous theoretical calculations based on the simplified model have only considered the energy exchange in the boundless condition.Under experimental conditions,however,the gas active medium must be guided by the metal waveguide.In this paper,we have developed a model of the energy exchange between a train of micro-bunches and a gas mixture active medium in a waveguide boundary for the first time,based on the theory of electromagnetic fields,and made detailed analysis and calculations with MathCAD.The results show that energy density can be optimized to a certain value to get the maximum energy exchange.

  5. Acceleration of a Monte Carlo radiation transport code

    Execution time for the Integrated TIGER Series (ITS) Monte Carlo radiation transport code has been reduced by careful re-coding of computationally intensive subroutines. Three test cases for the TIGER (1-D slab geometry), CYLTRAN (2-D cylindrical geometry), and ACCEPT (3-D arbitrary geometry) codes were identified and used to benchmark and profile program execution. Based upon these results, sixteen top time-consuming subroutines were examined and nine of them modified to accelerate computations with equivalent numerical output to the original. The results obtained via this study indicate that speedup factors of 1.90 for the TIGER code, 1.67 for the CYLTRAN code, and 1.11 for the ACCEPT code are achievable. copyright 1996 American Institute of Physics

  6. Electrostatic design and beam transport for a folded tandem electrostatic quadrupole accelerator facility for accelerator-based boron neutron capture therapy

    Within the frame of an ongoing project to develop a folded Tandem-Electrostatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT), we discuss here the electrostatic design of the machine, including the accelerator tubes with electrostatic quadrupoles and the simulations for the transport and acceleration of a high intensity beam.

  7. Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer

    Jeppesen, Stefan S; Schytte, Tine; Jensen, Henrik R;

    2013-01-01

    Abstract Introduction. Stereotactic body radiation therapy (SBRT) for early stage non-small cell lung cancer (NSCLC) is now an accepted and patient friendly treatment, but still controversy exists about its comparability to conventional radiation therapy (RT). The purpose of this single...... SBRT predicted improved prognosis. However, staging procedure, confirmation procedure of recurrence and technical improvements of radiation treatment is likely to influence outcomes. However, SBRT seems to be as efficient as conventional RT and is a more convenient treatment for the patients....

  8. Predicting Radiation Pneumonitis After Stereotactic Ablative Radiation Therapy in Patients Previously Treated With Conventional Thoracic Radiation Therapy

    Purpose: To determine the incidence of and risk factors for radiation pneumonitis (RP) after stereotactic ablative radiation therapy (SABR) to the lung in patients who had previously undergone conventional thoracic radiation therapy. Methods and Materials: Seventy-two patients who had previously received conventionally fractionated radiation therapy to the thorax were treated with SABR (50 Gy in 4 fractions) for recurrent disease or secondary parenchymal lung cancer (T 10 and mean lung dose (MLD) of the previous plan and the V10-V40 and MLD of the composite plan were also related to RP. Multivariate analysis revealed that ECOG PS scores of 2-3 before SABR (P=.009), FEV1 ≤65% before SABR (P=.012), V20 ≥30% of the composite plan (P=.021), and an initial PTV in the bilateral mediastinum (P=.025) were all associated with RP. Conclusions: We found that severe RP was relatively common, occurring in 20.8% of patients, and could be predicted by an ECOG PS score of 2-3, an FEV1 ≤65%, a previous PTV spanning the bilateral mediastinum, and V20 ≥30% on composite (previous RT+SABR) plans. Prospective studies are needed to validate these predictors and the scoring system on which they are based.

  9. Accelerator system for the Central Japan Synchrotron Radiation Facility

    Accelerator system for Central Japan Synchrotron Radiation Research Facility that consists of 50MeV electron S-band linac, 1.2GeV full energy booster synchrotron and 1.2GeV storage ring, has been constructed. Eight 1.4T bending magnets and four 5T superconducting magnet with compact refrigerator system provide beam lines. For top-up operation, the 1ns single bunch electron beam from 50MeV injector linac is injected by on-axis injection scheme and accelerated up to 1.2GeV at booster synchrotron. The timing system is designed for injection from booster ring is possible for any bunch position of storage ring. To improve efficiency of booster injection, the electron gun trigger and RF frequency of 2856MHz is synchronized with storage ring frequency of 499.654MHz. The EPICS control system is used with timing control system for linac, pulse magnet and also for booster pattern memory system. The beam commissioning for 1.2GeV storage ring has been progressing. (author)

  10. Radianttrademark Liquid Radioisotope Intravascular Radiation Therapy System

    RADIANTtrademark is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid β-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid β-source is Rhenium-188 in the form of sodium perrhenate (NaReO4), Rhenium-188 is primarily a β-emitter with a physical half-life of 17.0 hours. The maximum energy of the β-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Championtrademark over-the-wire, and TNTtrademark rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors

  11. Radiation therapy for the solitary plasmacytoma

    Esengül Koçak

    2010-06-01

    Full Text Available Plasma-cell neoplasms are classically categorized into four groups as: multiple myeloma (MM, plasma-cell leukemias, solitary plasmacytomas (SP of the bone (SPB, and extramedullary plasmacytomas (EMP. These tumors may be described as localized or diffuse in presentation. Localized plasma-cell neoplasms are rare, and include SP of the skeletal system, accounting for 2-5% of all plasma-cell neoplasms, and EMP of soft tissue, accounting for approximately 3% of all such neoplasms. SP is defined as a solitary mass of neoplastic plasma cells either in the bone marrow or in various soft tissue sites. There appears to be a continuum in which SP often progresses to MM. The main treatment modality for SP is radiation therapy (RT. However, there are no conclusive data in the literature on the optimal RT dose for SP. This review describes the interrelationship of plasma-cell neoplasms, and attempts to determine the minimal RT dose required to obtain local control.

  12. Liouville's equation and radiative acceleration in general relativity

    spacetimes. In the case of the Schwarzschild spacetime we find a solution of the Liouville equation which is invariant under the Killing vector symmetries and we adopt this as our model radiation field. Once a particular solution has been chosen the radiation field has been specified completely throughout the spacetime. In chapter 4 we investigate null and timelike geodesics in the Schwarzschild spacetime. Studying the null geodesics allows us to determine the viewing angles, that is, the (semi) angular size of the compact object as viewed by a stationary observer at an arbitrary point in the spacetime. The timelike geodesics are the trajectories of the (massive) test particles subject to no external radiation force and therefore constitute a limiting case of the radiative acceleration results. Given the radiation field one can calculate the radiation pressure force and because of special relativistic effects, the radiation pressure force experienced by the particle becomes velocity dependent. In chapter 5 we integrate the equations of motion for the case of purely radial motion in the Thomson limit. In this case we can obtain a tractable analytic expression for the solution in phase space, which can be compared with the high frequency case. In this chapter we consider a relativistic critical luminosity of a compact object, i.e. a relativistic Eddington luminosity. We also introduce and discuss terminal velocities and saturation velocities associated with a particular compact object. The terminal velocity of a radiation field is the 3-velocity required to annul the radiation pressure force on the test particle, neglecting the influence of any gravitational force on the particle. The saturation velocity is defined in the same way except the gravitational force is included. The saturation velocities are of course highly frequency dependent and provide important information about the dynamics of the system. In chapter 6 we discuss the Compton differential cross-section for

  13. Insufficiency fractures following radiation therapy for gynecologic malignancies

    The purpose of this study was to investigate the incidence, clinical and radiological findings of insufficiency fractures (IF) of the female pelvis following radiation therapy. We retrospectively reviewed the radiation oncology records of 108 patients with gynecologic malignancies who underwent external beam radiation therapy of the whole pelvis. All patients underwent conventional radiography and computed tomography (CT) scan every 6 months in follow-up after radiation therapy and magnetic resonance imaging (MRI) and radionuclide bone scan were added when the patients complained of pelvic pain. Thirteen of 108 patients (12%) developed IF in the irradiated field with a median interval of 6 months (range 3-51) from the completion of external beam radiation therapy. All patients who developed IF were postmenopausal women. Age of the patients who developed IF was significantly higher than that of the other patients. The parts of IF were sacroiliac joints, pubis, sacral body and 5th lumbar vertebra and six of 14 patients had multiple lesions. Treatment with rest and nonsteroidal anti-inflammatory drugs lead to symptomatic relief in all patients, although symptoms lasted from 3 to 20 months. Radiation-induced pelvic IF following radiation therapy for gynecologic malignancies were frequently observed in the post-menopausal patients within 1 year after external beam radiation therapy. Symmetrical fractures of the bilateral sacroiliac joint and pubis were the characteristic pattern of pelvic IF. All patients healed with conservative treatment, and nobody became non-ambulant. (author)

  14. Dosimetric and QA aspects of Konrad inverse planning system for commissioning intensity-modulated radiation therapy

    Deshpande Shrikant; Sathiyanarayanan V; Bhangle Janhavi; Swamy Kumara; Basu Sumit

    2007-01-01

    The intensity-modulated radiation therapy (IMRT) planning is performed using the Konrad inverse treatment planning system and the delivery of the treatment by using Siemens Oncor Impression Plus linear accelerator (step and shoot), which has been commissioned recently. The basic beam data required for commissioning the system were generate. The quality assurance of relative and absolute dose distribution was carried out before clinical implementation. The salient features of Konrad planning s...

  15. Optimization of adaptive radiation therapy in cervical cancer: Solutions for photon and proton therapy

    A.J.A.J. van de Schoot

    2016-01-01

    In cervical cancer radiation therapy, an adaptive strategy is required to compensate for interfraction anatomical variations in order to achieve adequate dose delivery. In this thesis, we have aimed at optimizing adaptive radiation therapy in cervical cancer to improve treatment efficiency and reduc

  16. 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

  17. Licensing process and implementation of a mobile linear accelerator for treatment of intraoperative radiation therapy; Proceso de licenciamiento e implantacion de un acelerador lineal movil para tratamientos de radioterapia intraoperatoria

    Sierra Diaz, F.; Gonzalez Ruiz, C.; Garcia Marcos, R.; Gallego Franco, P.; Rodriguez Checa, M.; Gomez Calvar, R.; Lopez Bote, M. A.

    2013-07-01

    The objective is to show how the working procedures, have been defined unambiguously to ensure together with the structure of the installation, and optimally located elements of radiation protection, compliance with the classification of areas, occupation factors and rates expected according to them. (Author)

  18. A New Type of Accelerator for Charged Particle Cancer Therapy

    Edgecock, Rob

    2016-01-01

    acceleration of protons and light ions for the treatment of certain cancers. They have unique features as they combine techniques from the existing types of accelerators, cyclotrons and synchrotrons, and hence look to have advantages over both for this application. However, these unique features meant that it was necessary to build one of these accelerators to show that it works and to undertake a detailed conceptual design of a medical machine. Both of these have now been done. This paper will describe the concepts of this type of accelerator, show results from the proof-of-principle machine (EMMA) and described the medical machine (PAMELA).

  19. Natural health products and cancer chemotherapy and radiation therapy

    Doreen Oneschuk

    2011-12-01

    Full Text Available Complementary therapies, notably natural health products such as herbs and vitamins, are frequently used by cancer patients receiving chemotherapy and radiation therapy. There is much controversy as to whether these natural health products should be taken during conventional cancer treatments. Supporters of this practice cite beneficial effects of the antioxidant properties, while opponents are concerned about the potential for natural health product-chemotherapy/radiation related negative interactions. This involves understanding the role and effect on metabolizing enzymes. This review will highlight the present evidence for both the beneficial and negative consequences of the use of natural health products during chemotherapy and radiation therapy.

  20. Radiation therapy and host immunity in malignant tumors

    Host resistance to the growth of neoplastic cells has been a subject of intense interest for many years. The recent demonstration that many tumors in man have tumor-associated antigens has provided a firm basis for experimental investigations of this resistance. Thus, it is important to determine whether radiation therapy for malignant tumors incurs detrimental effects on the host resistance. This article reviews the information on the relationship of radiation therapy to patient's immune status, and discusses the concept that in radiation therapy for cancer, the patient's immunological responses to the malignat tumor must be considered. (auth.)

  1. Occupational radiation protection around medical linear accelerators: measurements and semi-analytical approaches

    Full text: X-rays produced by high-energy (larger than 6 MeV) medical electron linear accelerators create secondary neutron radiation fields mainly by photonuclear reactions inside the materials of the accelerator head, the patient and the walls of the therapy room. Numerous papers were devoted to the study of neutron production in medical linear accelerators and resulting decay of activation products. However, data associated to doses delivered to workers in treatment conditions are scarce. In France, there are more than 350 external radiotherapy facilities representing almost all types of techniques and designs. IRSN carried out a measurement campaign in order to investigate the variation of the occupational dose according the different encountered situations. Six installations were investigated, associated with the main manufacturers (Varian, Elekta, General Electrics, Siemens), for several nominal energies, conventional and IMRT techniques, and bunker designs. Measurements were carried out separately for neutron and photon radiation fields, and for radiation associated with the decay of the activation products, by means of radiometers, tissue-equivalent proportional counters and spectrometers (neutron and photon spectrometry). They were performed at the positions occupied by the workers, i.e. outside the bunker during treatments, inside between treatments. Measurements have been compared to published data. In addition, semi-empirical analytical approaches recommended by international protocols were used to estimate doses inside and outside the bunkers. The results obtained by both approaches were compared and analysed. The annual occupational effective dose was estimated to about 1 mSv, including more than 50 % associated with the decay of activation products and less than 10 % due to direct exposure to leakage neutrons produced during treatments. (author)

  2. COMPARISON OF HYPOFRACTIONATED RADIATION THERAPY VERSUS CONVENTIONAL RADIATION THERAPY IN POST MASTECTOMY BREAST CANCER

    Abhilash

    2016-03-01

    Full Text Available INTRODUCTION Breast cancer is the most common cancer in women worldwide and a leading cause of cancer death in females and accounts for 1.8 million new cases and approximately 0.5 million deaths annually. Patients who present with locally advanced breast cancer (LABC require multidisciplinary team approach that incorporates diagnostic imaging, surgery, chemotherapy and histopathological assessment, including molecular-based studies, radiation, and, if indicated, biologic and hormonal therapies. Hypofractionated radiation therapy following mastectomy has been used in many institutions for several decades and have demonstrated equivalent local control, cosmetic and normal tissues between 50 Gy in 25 fractions and various hypofractionated radiotherapy prescriptions employing 13-16 fractions. Evidence suggests that hypofractionated radiotherapy may also be safe and effective for regional nodal disease. AIMS AND OBJECTIVES To compare the local control and side effects of hypofractionated radiation therapy with conventional radiation therapy in post mastectomy carcinoma breast with stage II and III and to compare the tolerability and compliance of both schedules. MATERIALS AND METHODS The study was conducted on 60 histopathologically proven patients of carcinoma of breast, treated surgically with modified radical mastectomy. Group I patients were given external radiation to chest flap and drainage areas, a dose of 39 Gy/13 fractions/3.1 weeks, a daily dose 3 Gy for 13 fractions in 4 days a week schedule and Group II patients were given external radiation to chest flap and drainage areas, a dose of 50 Gy/25 fractions/5 weeks, to receive a daily dose 2 Gy for 25 fractions in a 5 days a week schedule. RESULTS The median age at presentation in Group I and II was 48 and 50 years respectively. Locoregional control after completion of radiotherapy in Group I vs. Group II was 26/30 (86.7% vs. 27/30 (90% respectively. Acute reactions and their grades in Group

  3. CT findings of organizing pneumonia after radiation therapy in breast-conserving therapy for breast cancer

    Organizing pneumonia is known as a rare complication after radiation therapy in breast-conserving therapy for breast cancer. CT findings consist of consolidation and ground-glass opacities including the irradiated lung and patchy infiltrates in the nonirradiated lung. Steroid therapy is very effective, but relapse is frequently seen. In relapsed disease, lesions tend to appear in the different site from prior lesions. Radiologists should notice that organizing pneumonia is one form of radiation lung injury with good prognosis. (author)

  4. Stem Cell Therapy Remediates Reconstruction of the Craniofacial Skeleton After Radiation Therapy

    Deshpande, Sagar S.; Gallagher, Kathleen K.; Donneys, Alexis; Tchanque-Fossuo, Catherine N.; Sarhaddi, Deniz; Sun, Hongli; Krebsbach, Paul H; Buchman, Steven R.

    2013-01-01

    This study utilized transplanted bone marrow stromal cells (BMSCs) as a cellular replacement therapy to remedy radiation-induced injury and restore impaired new bone formation during distraction osteogenesis (DO). BMSC therapy brought about the successful generation of new bone and significantly improved both the rate and quality of a bony union of irradiated, distracted [X-ray radiation therapy (XRT)/DO] murine mandibles to the level of nonirradiated DO animals. The bone mineral density and ...

  5. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    Peucelle, C.; Martínez-Rovira, I.; Prezado, Y., E-mail: prezado@imnc.in2p3.fr [IMNC-UMR 8165, CNRS, Paris 7 and Paris 11 Universities, 15 rue Georges Clemenceau, Orsay Cedex 91406 (France); Nauraye, C.; Patriarca, A.; Hierso, E.; Fournier-Bidoz, N. [Institut Curie - Centre de Protonthérapie d’Orsay, Campus Universitaire, Bât. 101, Orsay 91898 (France)

    2015-12-15

    Purpose: Proton minibeam radiation therapy (pMBRT) is a new radiotherapy (RT) approach that allies the inherent physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. This dosimetry work aims at demonstrating the feasibility of the technical implementation of pMBRT. This has been performed at the Institut Curie - Proton Therapy Center in Orsay. Methods: Proton minibeams (400 and 700 μm-width) were generated by means of a brass multislit collimator. Center-to-center distances between consecutive beams of 3200 and 3500 μm, respectively, were employed. The (passive scattered) beam energy was 100 MeV corresponding to a range of 7.7 cm water equivalent. Absolute dosimetry was performed with a thimble ionization chamber (IBA CC13) in a water tank. Relative dosimetry was carried out irradiating radiochromic films interspersed in a IBA RW3 slab phantom. Depth dose curves and lateral profiles at different depths were evaluated. Peak-to-valley dose ratios (PVDR), beam widths, and output factors were also assessed as a function of depth. Results: A pattern of peaks and valleys was maintained in the transverse direction with PVDR values decreasing as a function of depth until 6.7 cm. From that depth, the transverse dose profiles became homogeneous due to multiple Coulomb scattering. Peak-to-valley dose ratio values extended from 8.2 ± 0.5 at the phantom surface to 1.08 ± 0.06 at the Bragg peak. This was the first time that dosimetry in such small proton field sizes was performed. Despite the challenge, a complete set of dosimetric data needed to guide the first biological experiments was achieved. Conclusions: pMBRT is a novel strategy in order to reduce the side effects of RT. This works provides the experimental proof of concept of this new RT method: clinical proton beams might allow depositing a (high) uniform dose in a brain tumor located in the center of the brain (7.5 cm depth

  6. Debate: Pro intraoperative radiation therapy in breast cancer; Debat: pour la radiotherapie peroperatoire dans le cancer du sein

    Dubois, J.B.; Lemanski, C.; Azria, D. [Departement de radiotherapie, CRLC Val-d' Aurelle-Paul-Lamarque, 208, rue des Apothicaires, 34298 Montpellier cedex 5 (France); Gutowski, M.; Rouanet, P.; Saint-Aubert, B. [Departement de chirurgie, CRLC Val-d' Aurelle-Paul-Lamarque, 208, rue des Apothicaires, 34298 Montpellier cedex 5 (France)

    2011-10-15

    The use of intraoperative radiation therapy in breast cancer patients started about 20 years ago. Several retrospective and prospective studies have been published. Intraoperative radiation therapy was initially given as a boost to the tumour bed, followed by whole-breast irradiation. These studies have demonstrated the feasibility of the technique, with local control rates and cosmetic results similar to those obtained with standard treatments. Accelerated partial breast irradiation yields local recurrence rates as low as those observed after whole-breast irradiation. Intraoperative radiation therapy as a single irradiation modality with a unique dose has been investigated in recent prospective studies showing satisfactory local results. Intraoperative radiation therapy can be proposed either as a boost or as a unique treatment in selected cases (tumour size, nodal and hormonal status, patient's age). Intraoperative radiation therapy can be delivered by orthovoltage (50 kV) X-rays from mobile generators, or by electrons from linear accelerators, mobile or fixed, dedicated or not to intraoperative radiation therapy. (authors)

  7. Hyperfractionated Accelerated Radiation Therapy (HART) of 70.6 Gy With Concurrent 5-FU/Mitomycin C Is Superior to HART of 77.6 Gy Alone in Locally Advanced Head and Neck Cancer: Long-term Results of the ARO 95-06 Randomized Phase III Trial

    Purpose: To report the long-term results of the ARO 95-06 randomized trial comparing hyperfractionated accelerated chemoradiation with mitomycin C/5-fluorouracil (C-HART) with hyperfractionated accelerated radiation therapy (HART) alone in locally advanced head and neck cancer. Patients and Methods: The primary endpoint was locoregional control (LRC). Three hundred eighty-four patients with stage III (6%) and IV (94%) oropharyngeal (59.4%), hypopharyngeal (32.3%), and oral cavity (8.3%) cancer were randomly assigned to 30 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total of 70.6 Gy concurrently with mitomycin C/5-FU (C-HART) or 16 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total dose of 77.6 Gy alone (HART). Statistical analyses were done with the log-rank test and univariate and multivariate Cox regression analyses. Results: The median follow-up time was 8.7 years (95% confidence interval [CI]: 7.8-9.7 years). At 10 years, the LRC rates were 38.0% (C-HART) versus 26.0% (HART, P=.002). The cancer-specific survival and overall survival rates were 39% and 10% (C-HART) versus 30.0% and 9% (HART, P=.042 and P=.049), respectively. According to multivariate Cox regression analysis, the combined treatment was associated with improved LRC (hazard ratio [HR]: 0.6 [95% CI: 0.5-0.8; P=.002]). The association between combined treatment arm and increased LRC appeared to be limited to oropharyngeal cancer (P=.003) as compared with hypopharyngeal or oral cavity cancer (P=.264). Conclusions: C-HART remains superior to HART in terms of LRC. However, this effect may be limited to oropharyngeal cancer patients

  8. Hyperfractionated Accelerated Radiation Therapy (HART) of 70.6 Gy With Concurrent 5-FU/Mitomycin C Is Superior to HART of 77.6 Gy Alone in Locally Advanced Head and Neck Cancer: Long-term Results of the ARO 95-06 Randomized Phase III Trial

    Budach, Volker, E-mail: volker.budach@charite.de [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Stromberger, Carmen [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Poettgen, Christoph [Department of Radiation Oncology, University Hospital of Essen (Germany); Baumann, Michael [Department of Radiation Oncology, University Hospital of Dresden (Germany); Budach, Wilfried [Department of Radiation Oncology, Heinrich Heine Universität Düsseldorf (Germany); Grabenbauer, Gerhard [Department of Radiation Oncology, University Hospitals of Erlangen (Germany); Marnitz, Simone [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany); Olze, Heidi [Department of Head and Neck Surgery, Charité Universitätsmedizin Berlin (Germany); Wernecke, Klaus-Dieter [Sostana GmbH, Berlin (Germany); Ghadjar, Pirus [Department of Radiation Oncology, Charité Universitätsmedizin Berlin (Germany)

    2015-04-01

    Purpose: To report the long-term results of the ARO 95-06 randomized trial comparing hyperfractionated accelerated chemoradiation with mitomycin C/5-fluorouracil (C-HART) with hyperfractionated accelerated radiation therapy (HART) alone in locally advanced head and neck cancer. Patients and Methods: The primary endpoint was locoregional control (LRC). Three hundred eighty-four patients with stage III (6%) and IV (94%) oropharyngeal (59.4%), hypopharyngeal (32.3%), and oral cavity (8.3%) cancer were randomly assigned to 30 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total of 70.6 Gy concurrently with mitomycin C/5-FU (C-HART) or 16 Gy/2 Gy daily followed by twice-daily 1.4 Gy to a total dose of 77.6 Gy alone (HART). Statistical analyses were done with the log-rank test and univariate and multivariate Cox regression analyses. Results: The median follow-up time was 8.7 years (95% confidence interval [CI]: 7.8-9.7 years). At 10 years, the LRC rates were 38.0% (C-HART) versus 26.0% (HART, P=.002). The cancer-specific survival and overall survival rates were 39% and 10% (C-HART) versus 30.0% and 9% (HART, P=.042 and P=.049), respectively. According to multivariate Cox regression analysis, the combined treatment was associated with improved LRC (hazard ratio [HR]: 0.6 [95% CI: 0.5-0.8; P=.002]). The association between combined treatment arm and increased LRC appeared to be limited to oropharyngeal cancer (P=.003) as compared with hypopharyngeal or oral cavity cancer (P=.264). Conclusions: C-HART remains superior to HART in terms of LRC. However, this effect may be limited to oropharyngeal cancer patients.

  9. Development of a Tandem-ElectroStatic-Quadrupole accelerator facility for Boron Neutron Capture Therapy (BNCT)

    There is a generalized perception that the availability of suitable particle accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of Boron Neutron Capture Therapy (BNCT). An ongoing project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based (AB)-BNCT is described here. The project goal is a machine capable of delivering 30 mA of 2.4-2.5 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p,n)7Be reaction slightly beyond its resonance at 2.25 MeV. A folded tandem, with 1.20-1.25 MV terminal voltage, combined with an ESQ chain is being designed and constructed. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the 7Li(p,n)7Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is one of the technologically simplest and cheapest solutions for optimized AB-BNCT. At present there is no BNCT facility in the world with the characteristics presented in this work. For the accelerator, results on its design, construction and beam transport calculations are discussed. Taking into account the peculiarities of the expected irradiation field, the project also considers a specific study of the treatment room. This study aims at the design of the treatment room emphasizing aspects related to patient, personnel and public radiation protection; dose monitoring; patient positioning and room construction. The design considers both thermal (for the treatment of shallow tumors) and epithermal (for deep-seated tumors) neutron beams entering the room through a port connected to the accelerator via a moderation and neutron beam shaping assembly. Preliminary results of dose calculations for the treatment room design, using the MCNP program, are presented

  10. Mesenchymal stem cell therapy for acute radiation syndrome.

    Fukumoto, Risaku

    2016-01-01

    Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation, such as that caused by detonation of nuclear devices and inappropriate medical treatments. Therefore, there is a growing need for medical interventions that facilitate the improved recovery of victims and patients. One promising approach may be cell therapy, which, when appropriately implemented, may facilitate recovery from whole body injuries. This editorial highlights the current knowledge regarding the use of mesenchymal stem cells for the treatment of acute radiation syndrome, the benefits and limitations of which are under investigation. Establishing successful therapies for acute radiation syndrome may require using such a therapeutic approach in addition to conventional approaches. PMID:27182446

  11. Optimization of Radiation Therapy Fractionation Schedules in the Presence of Tumor Repopulation

    Bortfeld, Thomas; Tsitsiklis, John N; Unkelbach, Jan

    2013-01-01

    We analyze the effect of tumor repopulation on optimal dose delivery in radiation therapy. We are primarily motivated by accelerated tumor repopulation towards the end of radiation treatment, which is believed to play a role in treatment failure for some tumor sites. A dynamic programming framework is developed to determine an optimal fractionation scheme based on a model of cell kill due to radiation and tumor growth in between treatment days. We find that faster tumor growth suggests shorter overall treatment duration. In addition, the presence of accelerated repopulation suggests larger dose fractions later in the treatment to compensate for the increased tumor proliferation. We prove that the optimal dose fractions are increasing over time. Numerical simulations indicate potential for improvement in treatment effectiveness.

  12. Optimization of adaptive radiation therapy in cervical cancer: Solutions for photon and proton therapy

    Schoot, van der, A.

    2016-01-01

    In cervical cancer radiation therapy, an adaptive strategy is required to compensate for interfraction anatomical variations in order to achieve adequate dose delivery. In this thesis, we have aimed at optimizing adaptive radiation therapy in cervical cancer to improve treatment efficiency and reduce radiation-induced toxicities. First, the clinically implemented adaptive strategy was described and the dosimetric consequences of this adaptive strategy compared to conventional non-adaptive rad...

  13. Chromatic energy filter and characterization of laser-accelerated proton beams for particle therapy

    Hofmann, Ingo; Meyer-ter-Vehn, Jürgen; Yan, Xueqing; Al-Omari, Husam

    2012-07-01

    The application of laser accelerated protons or ions for particle therapy has to cope with relatively large energy and angular spreads as well as possibly significant random fluctuations. We suggest a method for combined focusing and energy selection, which is an effective alternative to the commonly considered dispersive energy selection by magnetic dipoles. Our method is based on the chromatic effect of a magnetic solenoid (or any other energy dependent focusing device) in combination with an aperture to select a certain energy width defined by the aperture radius. It is applied to an initial 6D phase space distribution of protons following the simulation output from a Radiation Pressure Acceleration model. Analytical formula for the selection aperture and chromatic emittance are confirmed by simulation results using the TRACEWIN code. The energy selection is supported by properly placed scattering targets to remove the imprint of the chromatic effect on the beam and to enable well-controlled and shot-to-shot reproducible energy and transverse density profiles.

  14. Patient QA systems for rotational radiation therapy

    Fredh, Anna; Scherman, J.B.; Munck af Rosenschöld, Per Martin

    2013-01-01

    The purpose of the present study was to investigate the ability of commercial patient quality assurance (QA) systems to detect linear accelerator-related errors.......The purpose of the present study was to investigate the ability of commercial patient quality assurance (QA) systems to detect linear accelerator-related errors....

  15. Advanced laser particle accelerator development at LANL: from fast ignition to radiation oncology

    Flippo, Kirk A [Los Alamos National Laboratory; Gaillard, Sandrine A [Los Alamos National Laboratory; Offermann, D T [Los Alamos National Laboratory; Cobble, J A [Los Alamos National Laboratory; Schmitt, M J [Los Alamos National Laboratory; Gautier, D C [Los Alamos National Laboratory; Kwan, T J T [Los Alamos National Laboratory; Montgomery, D S [Los Alamos National Laboratory; Kluge, Thomas [FZD-GERMANY; Bussmann, Micheal [FZD-GERMANY; Bartal, T [UCSD; Beg, F N [UCSD; Gall, B [UNIV OF MISSOURI; Geissel, M [SNL; Korgan, G [NANOLABZ; Kovaleski, S [UNIV OF MISSOURI; Lockard, T [UNIV OF NEVADA; Malekos, S [NANOLABZ; Schollmeier, M [SNL; Sentoku, Y [UNIV OF NEVADA; Cowan, T E [FZD-GERMANY

    2010-01-01

    Laser-plasma accelerated ion and electron beam sources are an emerging field with vast prospects, and promise many superior applications in a variety of fields such as hadron cancer therapy, compact radioisotope generation, table-top nuclear physics, laboratory astrophysics, nuclear forensics, waste transmutation, SN M detection, and inertial fusion energy. LANL is engaged in several projects seeking to develop compact high current and high energy ion and electron sources. We are especially interested in two specific applications: ion fast ignition/capsule perturbation and radiation oncology in conjunction with our partners at the ForschungsZentrum Dresden-Rossendorf (FZD). Laser-to-beam conversion efficiencies of over 10% are needed for practical applications, and we have already shown inherent etliciencies of >5% from flat foils, on Trident using only a 5th of the intensity and energy of the Nova Petawatt. With clever target designs, like structured curved cone targets, we have also been able to achieve major ion energy gains, leading to the highest energy laser-accelerated proton beams in the world. These new target designs promise to help usher in the next generation of particle sources realizing the potential of laser-accelerated beams.

  16. Advanced laser particle accelerator development at LANL: from fast ignition to radiation oncology

    Laser-plasma accelerated ion and electron beam sources are an emerging field with vast prospects, and promise many superior applications in a variety of fields such as hadron cancer therapy, compact radioisotope generation, table-top nuclear physics, laboratory astrophysics, nuclear forensics, waste transmutation, SN M detection, and inertial fusion energy. LANL is engaged in several projects seeking to develop compact high current and high energy ion and electron sources. We are especially interested in two specific applications: ion fast ignition/capsule perturbation and radiation oncology in conjunction with our partners at the ForschungsZentrum Dresden-Rossendorf (FZD). Laser-to-beam conversion efficiencies of over 10% are needed for practical applications, and we have already shown inherent etliciencies of >5% from flat foils, on Trident using only a 5th of the intensity and energy of the Nova Petawatt. With clever target designs, like structured curved cone targets, we have also been able to achieve major ion energy gains, leading to the highest energy laser-accelerated proton beams in the world. These new target designs promise to help usher in the next generation of particle sources realizing the potential of laser-accelerated beams.

  17. Radiation Therapy Result of Polymorphic Reticulosis

    Chung, Eun Ji; Kim, Gwi Eon; Park, Young Nyun [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1993-06-15

    During the period from January, 1975, to June, 1989, one hundred patients with histopathologically proven polymorphic reticulosis in the upper respiratory tract were treated with radiation therapy and the analysis of treatment results was undertaken. One hundred patients (69 males, 31 females) with a mean age of 46 years (range 12-79 years) were presented. Nasal cavity was the most frequent site of involvement(56%), and 44 cases had multifocal sites of involvement. The incidence of cervical lymph node metastasis at initial diagnosis was 24%. Staging was determined by Ann-Arbor classification, retrospectively. The number of patients of stage IE, IIE, IIIE and IVE were 35, 60, 1, and 4, respectively. The overall 5 year actuarial survival rates were 38.4%. The difference in 5 year survival rates between patients with stage IE and IIE, with solitary and multiple, with CR and PR after irradiation were significant statistically. For the analysis of failure patterns, failure sites include the following: local failure alone(30/55=54.6%), systemic failure alone(9/55=16.4%), both local and systemic failure(16/55=29.0%). Retrograde slide review was available in 29 cases of PMR with respect to histopathologic bases, and immunohistochemical studies were performed using MTI and DACO-UCHL-1 as T-cell markers, MB2 as a B-cell marker and alpha-1-antichymotrypsin as a histiocytic markers. All that 29 cases showed characteristic histologic features similar to those of peripheral T-cell lymphoma and showed positive reactio to the T-cell marker. These findings suggest strongly that quite a significant portion of PMR may be in fact T-cell lymphoma.

  18. Results of radiation therapy for medulloblastoma

    Shibamoto, Yuta; Abe, Mitsuyuki; Tsutsui, Kazushige; Ono, Koji (Kyoto Univ. (Japan). Faculty of Medicine); Takahashi, Masaji

    1989-12-01

    Results of radiation therapy for cerebellar medulloblastoma at Kyoto University Hospital were reviewed. Between 1962 and 1988, 30 patients with histologically-proven medulloblastoma completed radiotherapy. Before 1971, the treatment volume was either the posterior fossa only or posterior fossa plus spinal axis, but after 1972, it was extended to include the entire neuraxis. The mean dose was 48 Gy to the posterior fossa, 36 Gy to the whole brain, and 25 Gy to the spinal axis. The 5-year survival rate and 5-year relapse-free survival rate estimated by the Kaplan-Meier's method were 36% and 37%, respectively, for total cases, but were as high as 79% and 80%, respectively, for the recent 10 patients. This improvement in the treatment results appeared to be due to extensive tumor resection and improved radiotherapy technique, and not to the use of chemotherapy. The prognosis was significantly better in patients treated with craniospinal irradiation than in those otherwise treated. There was a trend towards better survival in patients who received 50 Gy or more to the posterior fossa or 24 Gy or more to the spinal axis, compared to the patients who received lower doses to each site. No significant morbidity of radiotherapy was seen. Four of the six surviving patients who were treated below age 12 have a mental retardation and/or a short stature, but one patient treated at age 5 has a normal growth and a good intelligence. From these analysis, it is recommended to irradiate craniospinal axis and posterior fossa up to 25{approx}35 Gy and 50{approx}55 Gy, respectively. (author).

  19. Advances in Radiation Therapy in Pediatric Neuro-oncology.

    Bindra, Ranjit S; Wolden, Suzanne L

    2016-03-01

    Radiation therapy remains a highly effective therapy for many pediatric central nervous system tumors. With more children achieving long-term survival after treatment for brain tumors, late-effects of radiation have become an important concern. In response to this problem, treatment protocols for a variety of pediatric central nervous system tumors have evolved to reduce radiation fields and doses when possible. Recent advances in radiation technology such as image guidance and proton therapy have led to a new era of precision treatment with significantly less exposure to healthy tissues. These developments along with the promise of molecular classification of tumors and targeted therapies point to an optimistic future for pediatric neuro-oncology. PMID:26271789

  20. Late effects of radiation therapy in the treatment of Hodgkin's disease

    In the last two decades, a considerable amount of clinical and experimental animal data has been accumulated regarding the tolerance of the major normal tissues and organs traversed by the radiation beams in treating Hodgkin's disease. Typically, the tolerance of several tissues and organs must be considered in designing the very large radiation portals such as the mantle. Today, sophisticated machinery such as computerized tomography scanners, simulators, computers, and linear accelerators are available to improve the radiation planning and treatment of Hodgkin's disease. In this paper, researchers discuss the late effects of radiation therapy to the lung, heart, thyroid, kidney, gastrointestinal tract, and the gonads of adults with Hodgkin's disease. Emphasis is placed on our recommendations for modifications of radiation technique to improve the complication-free cure rate

  1. Direct aperture optimization for online adaptive radiation therapy

    This paper is the first investigation of using direct aperture optimization (DAO) for online adaptive radiation therapy (ART). A geometrical model representing the anatomy of a typical prostate case was created. To simulate interfractional deformations, four different anatomical deformations were created by systematically deforming the original anatomy by various amounts (0.25, 0.50, 0.75, and 1.00 cm). We describe a series of techniques where the original treatment plan was adapted in order to correct for the deterioration of dose distribution quality caused by the anatomical deformations. We found that the average time needed to adapt the original plan to arrive at a clinically acceptable plan is roughly half of the time needed for a complete plan regeneration, for all four anatomical deformations. Furthermore, through modification of the DAO algorithm the optimization search space was reduced and the plan adaptation was significantly accelerated. For the first anatomical deformation (0.25 cm), the plan adaptation was six times more efficient than the complete plan regeneration. For the 0.50 and 0.75 cm deformations, the optimization efficiency was increased by a factor of roughly 3 compared to the complete plan regeneration. However, for the anatomical deformation of 1.00 cm, the reduction of the optimization search space during plan adaptation did not result in any efficiency improvement over the original (nonmodified) plan adaptation. The anatomical deformation of 1.00 cm demonstrates the limit of this approach. We propose an innovative approach to online ART in which the plan adaptation and radiation delivery are merged together and performed concurrently--adaptive radiation delivery (ARD). A fundamental advantage of ARD is the fact that radiation delivery can start almost immediately after image acquisition and evaluation. Most of the original plan adaptation is done during the radiation delivery, so the time spent adapting the original plan does not

  2. Superficial Radiation Therapy for the Treatment of Nonmelanoma Skin Cancers

    Minni, John; Herold, David

    2015-01-01

    Superficial radiation therapy has become more widely available to dermatologists. With the advent of more portable machines, it has become more convenient for dermatology practices to employ in an office-based setting. The goal of this paper is to provide a deeper insight into the role of superficial radiation therapy in dermatology practice and to review the current literature surrounding its use in the treatment of both basal and squamous cell carcinomas. PMID:26705443

  3. Clinical Oral Examinations: Assessment of Competency in Radiation Therapy

    Leech, Michelle; POOLE, CLAIRE; CRAIG, AGNELLA; COFFEY, MARY ANNE; NI CHUINNEAGAIN, SIOBHAN

    2009-01-01

    Matching assessment strategies to learning outcomes in radiation therapy education is of the utmost importance. Assessing clinical competence requires that `competence? be clearly defined prior to the start of any clinical programme. In this article, we report on our experience in using clinical oral examinations in assessing competence in second year undergraduate radiation therapy students. The shortcomings of clinical oral examinations such as `leaking? of the agenda are addressed and more...

  4. Natural health products and cancer chemotherapy and radiation therapy

    Doreen Oneschuk; Jawaid Younus

    2011-01-01

    Complementary therapies, notably natural health products such as herbs and vitamins, are frequently used by cancer patients receiving chemotherapy and radiation therapy. There is much controversy as to whether these natural health products should be taken during conventional cancer treatments. Supporters of this practice cite beneficial effects of the antioxidant properties, while opponents are concerned about the potential for natural health product-chemotherapy/radiation related negative in...

  5. Pneumothorax following thoracic radiation therapy for Hodgkin's disease

    Radiation therapy alone to the nodal drainage sites above the diaphragm, namely a ''mantle'' field, is often standard treatment for early stage Hodgkin's disease and may be used in combination with chemotherapy in more advanced disease. Localised pneumonitis and fibrosis are recognised treatment related sequelae; however, other pulmonary complications, including pneumothorax, have been described. Two cases of spontaneous pneumothorax following mantle radiation therapy are presented. (author)

  6. Factors influencing radiation therapy student clinical placement satisfaction

    Bridge, Pete; Carmichael, Mary-Ann

    2014-01-01

    Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clini...

  7. The personnel protection system for a Synchrotron Radiation Accelerator Facility: Radiation safety perspective

    The Personnel Protection System (PPS) at the Stanford Synchrotron Radiation Laboratory is summarized and reviewed from the radiation safety point of view. The PPS, which is designed to protect people from radiation exposure to beam operation, consists of the Access Control System (ACS) and the Beam Containment System (BCS), The ACS prevents people from being exposed to the very high radiation level inside the shielding housing (also called a PPS area). The ACS for a PPS area consists of the shielding housing and a standard entry module at every entrance. The BCS prevents people from being exposed to the radiation outside a PPS area due to normal and abnormal beam losses. The BCS consists of the shielding (shielding housing and metal shielding in local areas), beam stoppers, active current limiting devices, and an active radiation monitor system. The system elements for the ACS and BCS and the associated interlock network are described. The policies and practices in setting up the PPS are compared with some requirements in the US Department of Energy draft Order of Safety of Accelerator Facilities

  8. Thyroid neoplasia following radiation therapy for Hodgkin's lymphoma

    The question of thyroid neoplasia following high-dose radiation treatment to the neck and mediastinum for malignant neoplasms such as Hodgkin's lymphoma in children and young adults has been raised recently. Five patients, 19 to 39 years old, were operated on for thyroid neoplasms that developed following cervical and mediastinal radiation therapy for Hodgkin's lymphoma. Three patients had papillary carcinomas and two had follicular adenomas. The latency period between radiation exposure and the diagnosis of thyroid neoplasm ranged from eight to 16 years. This limited series provided strong support for the recommendation that children and young adults who are to receive high-dose radiation therapy to the head, neck, and mediastinum should receive suppressive doses of thyroxine prior to radiation therapy in order to suppress thyrotropin (thyroid-stimulating hormone) and then be maintained on a regimen of suppression permanently

  9. Report of an accidental exposure of patients in radiation therapy

    Full text. Accident with radiation therapy patients, when they happen, have a high probability of being very severe. This paper reports an accident that occurred last November in Brazil involving several patients submitted to therapy with clinical electron beams from 6 to 12 MeV. A field response team from the Instituto de Radioprotecao e Dosimetria (IRD), and the Laboratorio de Ciencias Radiologicas (LCR/DBB/UERJ), was sent to identify the causes of the accident and evaluate its consequences. The report suggests several actions to be observed by regulatory authorities, licensees and several other legal persons and individuals with subsidiary responsibilities. Evaluation of radiologic accidents is important because it permits to introduce the lessons learned in the radiation protection system, including design of equipment and installations, radiation procedures and personnel qualification and because it renders and attitude of continuous alert so a non usual event will not run into an accident. The accident A 'flat/sym'interlock problem occurred with the electron beam of a Mevatron-74 linear accelerator. After consulting the physicist, the technicians operated the equipment on the 'research mode' (non-clinical). Later the physicist came to verify the equipment and noticed that the dose rate presented high oscillation and that the 'pgm/norm'key was set to 'pgm'. After setting the control to 'norm'the equipment resumed working and some patients were treated in clinical mode and some in research mode. The machine then stops working and the service personnel were called. On 11/28 the maintenance technician fixed the equipment and the physicist measured the dose rate under 'pgm'mode and notice that it was about eight times over the normal value. COnclusion: the working group concluded that the accident could happen only if the equipment were operated on non-clinical mode. It can be summarized as : The event initiator: the flat/sym interlock. The accident promoter: the

  10. Persistence of endometrial activity after radiation therapy for cervical carcinoma

    Radiation therapy is a proved treatment for cervical carcinoma; however, it destroys ovarian function and has been thought to ablate the endometrium. Estrogen replacement therapy is often prescribed for patients with cervical carcinoma after radiation therapy. A review of records of six teaching hospitals revealed 16 patients who had endometrial sampling for uterine bleeding after standard radiation therapy for cervical carcinoma. Fifteen patients underwent dilatation and curettage, and one patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy when a dilatation and curettage was unsuccessful. Six patients had fibrosis and inflammation of the endometrial cavity, seven had proliferative endometrium, one had cystic hyperplasia, one had atypical adenomatous hyperplasia, and one had adenocarcinoma. Although the number of patients who have an active endometrium after radiation therapy for cervical carcinoma is not known, this report demonstrates that proliferative endometrium may persist, and these patients may develop endometrial hyperplasia or adenocarcinoma. Studies have indicated that patients with normal endometrial glands have an increased risk of developing endometrial adenocarcinoma if they are treated with unopposed estrogen. Patients who have had radiation therapy for cervical carcinoma should be treated with estrogen and a progestational agent to avoid endometrial stimulation from unopposed estrogen therapy

  11. Clinical study on sulpyrin therapy for radiation pneumonitis

    Yagi, Susumu; Watanabe, Masatoshi; Hashiguchi, Kohji; Kimura, Masashi; Sumi, Masaru; Umeki, Shigenobu; Hara, Hiroki; Soejima, Rinzo (Kawasaki Medical School, Kurashiki, Okayama (Japan))

    1990-11-01

    Radiation therapy is an effective treatment for cancer, however, irradiation of the chest may cause radiation pneumonitis as a severe pulmonary complication. Although this condition is responsive to steroid therapy, it is well known that therapy is an increased vulnerability to various infections in patients receiving long-term steroid therapy and exacerbation of the disease associated with a reduction in the dose. In this study, 10 patients with radiation pneumonitis received 3 divided daily oral of 0.9{similar to}1.2 g/day (15 mg/kg) of sulpyrin. The patients' fever disappeared within a few days after the beginning of treatment. Pneumonitis was roentgenographically stabilized, although the fibrotic and atrophic changes continued. No exacerbation of the disease was observed even after discontinuation of the therapy and the outcomes of all patients was satisfactory. These results suggest that sulpyrin was clinically effective for radiation pneumonitis, probably resulting from an anti-inflammatory effect due to prostaglandin synthesis inhibition. In the acute phase of radiation pneumonitis, the introduction of steroids appears to be delayed. This sulpyrin therapy may be a useful alternative for cases in which the steroid therapy in contraindicated. (author).

  12. Radiation dermatitis following electron beam therapy

    Ten patients, who had been treated for mycosis fungoides with electron beam radiation ten or more years previously, were examined for signs of radiation dermatitis. Although most patients had had acute radiation dermatitis, only a few manifested signs of mild chronic changes after having received between 1,000 and 2,800 rads

  13. Spontaneous pneumothorax after upper mantle radiation therapy for Hodgkin disease

    Between 1967 and 1981, 158 of 256 consecutive adult patients received upper mantle (UM) radiation therapy as part of initial treatment of Hodgkin disease at the Hamilton Regional Cancer Centre. Chemotherapy was also part of the initial treatment in 21 of 158 patients who received UM radiation therapy. Spontaneous pneumothorax was observed in six of 158 patients during remission after UM radiation therapy in this series. Three cases were incidental findings on follow-up radiographs, but three other patients were seen initially with symptoms of spontaneous pneumothorax. The entity occurred in three of 21 patients (14%) treated with UM radiation therapy and chemotherapy, and in three of 137 (2%) treated with UM radiation therapy (P < .05). Within the range of UM doses (3,500-4,000 cGy in 4 weeks), higher dose was not associated with higher risk of spontaneous pneumothorax. Although these cases of spontaneous pneumothorax are clustered in an age range classic for this entity, the incidence of spontaneous pneumothorax in this group of patients is higher than the anticipated lifetime incidence of 1:500 for the general population. This risk of spontaneous pneumothorax after UM radiation therapy may be even higher in patients who also receive chemotherapy

  14. Hawking Radiation of Dirac Particles in an Arbitrarily Accelerating Kinnersley Black Hole

    Wu, S Q

    2002-01-01

    Quantum thermal effect of Dirac particles in an arbitrarily accelerating Kinnersley black hole is investigated by using the method of generalized tortoise coordinate transformation. Both the location and the temperature of the event horizon depend on the advanced time and the angles. The Hawking thermal radiation spectrum of Dirac particles contains a new term which represents the interaction between particles with spin and black holes with acceleration. This spin-acceleration coupling effect is absent from the thermal radiation spectrum of scalar particles.

  15. Optimized laser pulse profile for efficient radiation pressure acceleration of ions

    Bulanov, S. S.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.

    2012-01-01

    The radiation pressure acceleration regime of laser ion acceleration requires high intensity laser pulses to function efficiently. Moreover the foil should be opaque for incident radiation during the interaction to ensure maximum momentum transfer from the pulse to the foil, which requires proper matching of the target to the laser pulse. However, in the ultrarelativistic regime, this leads to large acceleration distances, over which the high laser intensity for a Gaussian laser pulse must be...

  16. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

    Gay, Hiram A., E-mail: hgay@radonc.wustl.edu [Washington University School of Medicine, St Louis, MO (United States); Barthold, H. Joseph [Commonwealth Hematology and Oncology, Weymouth, MA (United States); Beth Israel Deaconess Medical Center, Boston, MA (Israel); O' Meara, Elizabeth [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Bosch, Walter R. [Washington University School of Medicine, St Louis, MO (United States); El Naqa, Issam [Department of Radiation Oncology, McGill University Health Center, Montreal, Quebec (Canada); Al-Lozi, Rawan [Washington University School of Medicine, St Louis, MO (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Zietman, Anthony [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Myerson, Robert [Washington University School of Medicine, St Louis, MO (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Portelance, Lorraine [University of Miami, Miami, FL (United States); Ryu, Janice [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); and others

    2012-07-01

    Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

  17. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

    Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, AdnexaR, AdnexaL, Prostate, SeminalVesc, PenileBulb, FemurR, and FemurL. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

  18. Radiation therapy in the treatment of macular degeneration: a review

    Macular degeneration is a major health problem. Less than 10 % of the cases can be successfully treated by laser therapy. Low dose radiation therapy (in the range of 20 Gy) appears to decrease neo-vascularization. These early results need to be confirmed through a randomized trial. (author)

  19. Physical basis of heavy-ion radiation therapy

    Kanai, Tatsuaki [National Inst. of Radiological Sciences, Chiba (Japan). Research Center of Charged Particle Therapy

    2000-04-01

    We have treated over 700 patients at HIMAC (Heavy Ion Medical Accelerator in Chiba) using carbon beams since 1994. We have started this clinical trial of heavy-ion radiotherapy with various assumptions about radiosensitivity of tumor and normal tissues to the heavy-ion beams. Spread-out Bragg peaks are designed based on the responses of HSG (human salivary grand tumor cell) cells. RBE of the carbon beams is determined following neutron treatment. The neutron treatment schedule of 18 fractions and a fractional dose of 0.9 Gy and 3.0 of RBE was applied to the carbon radiotherapy. In these 5 years, clinical optimization of the irradiation dose and fractionations and total treatment time were studied under strict control of authorized clinical protocols of heavy-ion radiation therapy. The finding of the clinical research of the optimization tell us that it can be safely treated with short treatment time or large fractional dose which are considerably deviated from the assumed treatment schedule. Comparisons of the schedules of carbon treatments were discussed using LQ model. In the analysis, very simplified model of the carbon beam was used. From these discussions, it was shown that we could safely reduce a total treatment time increasing dose of one fraction. (author)

  20. Optimization of protection of patients in radiation therapy

    Radiotherapy has been one of the main modalities of cancer treatment. Cancer patients are deliberately exposed to high doses of radiation with the aim of complete cure or palliation. Radiation therapy consists of complex processes involving several professionals working in interrelated activities and requiring the use of sophisticated equipment. Optimization of patient protection aims to prevent accidental exposures at any stage of the process. In the course of the treatment, normal tissues receive considerable amount of radiation which can lead to side effects or complications. Optimum treatment is achieved by delivering maximum dose to the target but minimum dose to the critical structures thus decreasing the possibility of developing unwanted complications. There are various ways designed to achieve this objective. These includes the following: the use of customized blocks which has been the standard practice in conventional two-dimensional radiotherapy; the innovative design of the multileaf collimator which together with advancement in imaging techniques and in computer technology have revolutionized the practice of radiotherapy in the last decade leading to the growth of 3-D conformal radiation therapy (3-D CRT) and intensity modulated radiation therapy (IMRT) and finally the use of imaging in image guided radiation therapy (IGRT). These advance techniques in radiation therapy will be discussed in the context of optimization of medical exposures. (author)

  1. Focal Therapy, Differential Therapy, and Radiation Treatment for Prostate Cancer

    Jain, Anudh K.; Ennis, Ronald D

    2012-01-01

    Focal and differential therapy represent an approach to improve the therapeutic ratio of prostate cancer treatments. This concept is a shift from treating the whole gland to intensely treating the portion of the gland that contains significant tumor. However, there are many challenges in the move towards focal approaches. Defining which patients are suitable candidates for focal therapy approaches is an area of significant controversy, and it is likely that additional data from imaging or det...

  2. Hadron accelerators in medicine

    The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadron-therapy Project is then described in some detail, with reference ro both the National Centre for Oncological Hadron-therapy and the design of different types of compact proton accelerators aimed at introducing proton therapy in a large umber of hospitals. (author)

  3. Hypofractionated Radiation Therapy for Breast Ductal Carcinoma In Situ

    Purpose: Conventional radiation therapy (RT) administered in 25 fractions after breast-conserving surgery (BCS) is the standard treatment for ductal carcinoma in situ (DCIS) of the breast. Although accelerated hypofractionated regimens in 16 fractions have been shown to be equivalent to conventional RT for invasive breast cancer, few studies have reported results of using hypofractionated RT in DCIS. Methods and Materials: In this multicenter collaborative effort, we retrospectively reviewed the records of all women with DCIS at 3 institutions treated with BCS followed by hypofractionated whole-breast RT (WBRT) delivered in 16 fractions. Results: Between 2003 and 2010, 440 patients with DCIS underwent BCS followed by hypofractionated WBRT in 16 fractions for a total dose of 42.5 Gy (2.66 Gy per fraction). Boost RT to the surgical bed was given to 125 patients (28%) at a median dose of 10 Gy in 4 fractions (2.5 Gy per fraction). After a median follow-up time of 4.4 years, 14 patients had an ipsilateral local relapse, resulting in a local recurrence-free survival of 97% at 5 years. Positive surgical margins, high nuclear grade, age less than 50 years, and a premenopausal status were all statistically associated with an increased occurrence of local recurrence. Tumor hormone receptor status, use of adjuvant hormonal therapy, and administration of additional boost RT did not have an impact on local control in our cohort. On multivariate analysis, positive margins, premenopausal status, and nuclear grade 3 tumors had a statistically significant worse local control rate. Conclusions: Hypofractionated RT using 42.5 Gy in 16 fractions provides excellent local control for patients with DCIS undergoing BCS

  4. Hypofractionated Radiation Therapy for Breast Ductal Carcinoma In Situ

    Hathout, Lara [Department of Radiation Oncology, Hôpital Maisonneuve-Rosemont, Centre affilié à l' Université de Montréal, Montreal, Quebec (Canada); Hijal, Tarek [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Théberge, Valérie [Department of Radiation Oncology, Centre hospitalier universitaire de Québec, L' Hôtel-Dieu de Québec, Quebec (Canada); Centre des maladies du sein Deschênes-Fabia, Quebec (Canada); Fortin, Bernard [Department of Radiation Oncology, Hôpital Maisonneuve-Rosemont, Centre affilié à l' Université de Montréal, Montreal, Quebec (Canada); Vulpe, Horia [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Hogue, Jean-Charles [Centre des maladies du sein Deschênes-Fabia, Quebec (Canada); Centre hospitalier universitaire de Québec, Hôpital St-Sacrement, Quebec (Canada); Lambert, Christine [Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Bahig, Houda [Department of Radiation Oncology, Hôpital Maisonneuve-Rosemont, Centre affilié à l' Université de Montréal, Montreal, Quebec (Canada); and others

    2013-12-01

    Purpose: Conventional radiation therapy (RT) administered in 25 fractions after breast-conserving surgery (BCS) is the standard treatment for ductal carcinoma in situ (DCIS) of the breast. Although accelerated hypofractionated regimens in 16 fractions have been shown to be equivalent to conventional RT for invasive breast cancer, few studies have reported results of using hypofractionated RT in DCIS. Methods and Materials: In this multicenter collaborative effort, we retrospectively reviewed the records of all women with DCIS at 3 institutions treated with BCS followed by hypofractionated whole-breast RT (WBRT) delivered in 16 fractions. Results: Between 2003 and 2010, 440 patients with DCIS underwent BCS followed by hypofractionated WBRT in 16 fractions for a total dose of 42.5 Gy (2.66 Gy per fraction). Boost RT to the surgical bed was given to 125 patients (28%) at a median dose of 10 Gy in 4 fractions (2.5 Gy per fraction). After a median follow-up time of 4.4 years, 14 patients had an ipsilateral local relapse, resulting in a local recurrence-free survival of 97% at 5 years. Positive surgical margins, high nuclear grade, age less than 50 years, and a premenopausal status were all statistically associated with an increased occurrence of local recurrence. Tumor hormone receptor status, use of adjuvant hormonal therapy, and administration of additional boost RT did not have an impact on local control in our cohort. On multivariate analysis, positive margins, premenopausal status, and nuclear grade 3 tumors had a statistically significant worse local control rate. Conclusions: Hypofractionated RT using 42.5 Gy in 16 fractions provides excellent local control for patients with DCIS undergoing BCS.

  5. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    Brown, Lindsay [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Harmsen, William [Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota (United States); Blanchard, Miran [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Goetz, Matthew [Division of Medical Oncology, Mayo Clinic, Rochester, Minnesota (United States); Jakub, James [Department of Surgery, Mayo Clinic, Rochester, Minnesota (United States); Mutter, Robert; Petersen, Ivy; Rooney, Jessica [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Stauder, Michael [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Yan, Elizabeth [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Laack, Nadia, E-mail: laack.nadia@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2014-08-01

    Purpose: Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer variant treated with multimodality therapy. A variety of approaches intended to escalate the intensity and efficacy of radiation therapy have been reported, including twice-daily radiation therapy, dose escalation, and aggressive use of bolus. Herein, we examine our outcomes for patients treated with once-daily radiation therapy with aggressive bolus utilization, focusing on treatment technique. Methods and Materials: A retrospective review of patients with nonmetastatic IBC treated from January 1, 2000, through December 31, 2010, was performed. Locoregional control (LRC), disease-free survival (DFS), overall survival (OS) and predictors thereof were assessed. Results: Fifty-two women with IBC were identified, 49 (94%) of whom were treated with neoadjuvant chemotherapy. All underwent mastectomy followed by adjuvant radiation therapy. Radiation was delivered in once-daily fractions of 1.8 to 2.25 Gy (median, 2 Gy). Patients were typically treated with daily 1-cm bolus throughout treatment, and 33 (63%) received a subsequent boost to the mastectomy scar. Five-year Kaplan Meier survival estimates for LRC, DFS, and OS were 81%, 56%, and 64%, respectively. Locoregional recurrence was associated with poorer OS (P<.001; hazard ratio [HR], 4.1). Extracapsular extension was associated with worse LRC (P=.02), DFS (P=.007), and OS (P=.002). Age greater than 50 years was associated with better DFS (P=.03). Pathologic complete response was associated with a trend toward improved LRC (P=.06). Conclusions: Once-daily radiation therapy with aggressive use of bolus for IBC results in outcomes consistent with previous reports using various intensified radiation therapy regimens. LRC remains a challenge despite modern systemic therapy. Extracapsular extension, age ≤50 years, and lack of complete response to chemotherapy appear to be associated with worse outcomes. Novel strategies are needed in IBC

  6. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    Purpose: Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer variant treated with multimodality therapy. A variety of approaches intended to escalate the intensity and efficacy of radiation therapy have been reported, including twice-daily radiation therapy, dose escalation, and aggressive use of bolus. Herein, we examine our outcomes for patients treated with once-daily radiation therapy with aggressive bolus utilization, focusing on treatment technique. Methods and Materials: A retrospective review of patients with nonmetastatic IBC treated from January 1, 2000, through December 31, 2010, was performed. Locoregional control (LRC), disease-free survival (DFS), overall survival (OS) and predictors thereof were assessed. Results: Fifty-two women with IBC were identified, 49 (94%) of whom were treated with neoadjuvant chemotherapy. All underwent mastectomy followed by adjuvant radiation therapy. Radiation was delivered in once-daily fractions of 1.8 to 2.25 Gy (median, 2 Gy). Patients were typically treated with daily 1-cm bolus throughout treatment, and 33 (63%) received a subsequent boost to the mastectomy scar. Five-year Kaplan Meier survival estimates for LRC, DFS, and OS were 81%, 56%, and 64%, respectively. Locoregional recurrence was associated with poorer OS (P<.001; hazard ratio [HR], 4.1). Extracapsular extension was associated with worse LRC (P=.02), DFS (P=.007), and OS (P=.002). Age greater than 50 years was associated with better DFS (P=.03). Pathologic complete response was associated with a trend toward improved LRC (P=.06). Conclusions: Once-daily radiation therapy with aggressive use of bolus for IBC results in outcomes consistent with previous reports using various intensified radiation therapy regimens. LRC remains a challenge despite modern systemic therapy. Extracapsular extension, age ≤50 years, and lack of complete response to chemotherapy appear to be associated with worse outcomes. Novel strategies are needed in IBC

  7. Hypofractionated radiation therapy for the treatment of feline facial squamous cell carcinoma; Hypofractionated radiation therapy for the treatment of feline facial squamous cell carcinoma

    Cunha, S.C.S.; Corgozinho, K.B.; Holguin, P.G.; Ferreira, A.M.R., E-mail: simonecsc@gmail.co [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Carvalho, L.A.V. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil); Canary, P.C.; Reisner, M. [Hospital Universitario Clementino Fraga Filho (HUCFF/UFRJ), Rio de Janeiro, RJ (Brazil); Pereira, A.N.; Souza, H.J.M. [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil)

    2010-07-01

    The efficacy of hypofractionated radiation protocol for feline facial squamous cell carcinoma was evaluated. Hypofractionated radiation therapy was applied to five cats showing single or multiple facial squamous cell carcinomas, in a total of ten histologically confirmed neoplastic lesions. Of the lesions, two were staged as T{sub 1}, four as T{sub 2}, two as T{sub 3}, and two as T{sub 4}. The animals were submitted to four radiation fractions from 7.6 to 10 grays each, with one week intervals. The equipment was a linear accelerator with electrons beam. The cats were evaluated weekly during the treatment and 30 and 60 days after the end of the radiation therapy. In this study, 40% of the lesions had complete remission, 40% partial remission, and 20% did not respond to the treatment. Response rates were lower as compared to other protocols previously used. However, hypofractionated radiation protocol was considered safe for feline facial squamous cell carcinoma. (author)

  8. Cranial Radiation Therapy and Damage to Hippocampal Neurogenesis

    Monje, Michelle

    2008-01-01

    Cranial radiation therapy is associated with a progressive decline in cognitive function, prominently memory function. Impairment of hippocampal neurogenesis is thought to be an important mechanism underlying this cognitive decline. Recent work has elucidated the mechanisms of radiation-induced failure of neurogenesis. Potential therapeutic…

  9. The therapy of marrowy syndrome at radiation lesions

    In this chapter author made conclusion that cumulative data on experimental therapy of radiation affections testify to the effect that at critical radiation sickness of heavy level following hematosis oppression effective can be only that treatment regimen, which contains resources conducive to reducing processes in the marrow

  10. The Radiation Therapy Oncology in the context of oncological practice

    This work is about the radiation therapy oncology in the context of oncological practice. The radiotherapy is a speciality within medicine that involves the generation, application and dissemination of knowledge about the biology, causes, prevention and treatment of the cancer and other pathologies by ionising radiation

  11. Accelerator driven radiation clean nuclear power system conceptual research symposium

    The R and D of ADS (Accelerators Driven Subcritical System) in China introduced. 31 theses are presented. It includes the basic principle of ADS, accelerators, sub-critical reactors, neutron physics, nuclear data, partitioning and transmutation

  12. Dosimetric verification in intensity modulated radiation therapy

    As part of dosimetric verification for IMRT intensity modulated radiation therapy, we examined the selection of a dosimeter in accordance with the purpose of physical measurement and the process of data analysis. Because of the high dose conformation in the target volume and minimum dose in the organs at risk (OAR) in IMRT, dosimetric verification is essential. Because the performance of dosimetric verification in a patient is not allowed, a physical phantom and dosimeter must be used. Dose verification using a physical phantom, from which the beam data optimized for a patient slated for IMRT are transferred, may cause latent error as a result of change in the depth of each beam toward an isocenter. This effect may change the dose distribution and prescription dose. The basic methods of dosimetric verification with physical measurement are point dosimetry, when the reference dose is given at a point by planning software, and volumetric dosimetry, when planning software gives the dose as a volumetric configuration. While the most accurate dosimetry is done using a calibrated ionization chamber, IMRT requires volumetric dosimetry using some kind of portal film or a polymer gel dosimeter, because of the need for dosimetric verification for an irregular dose distribution in IMRT. The importance of indirect dosimetry using these methods is to provide calibration as a dosimeter, absolute dose, and preservation of calibration. In our study, the verification of dose distribution for IMRT using portal film and RANDO phantom could be performed with an error of less than 2% in all cases. The measurement error for the central dose using a JARP-type ionization chamber and MixDP was less than 3% in all cases except for the case with the maximum error. At the moment, IMRT requires a great deal of effort in the processes of planning, dosimetric verification, and isocenter checking in every fraction to maintain high accuracy. Although the need for a large amount of effort in the

  13. Anesthesia for pediatric external beam radiation therapy

    Background: For very young patients, anesthesia is often required for radiotherapy. This results in multiple exposures to anesthetic agents over a short period of time. We report a consecutive series of children anesthetized for external beam radiation therapy (EBRT). Methods: Five hundred twelve children ≤ 16 years old received EBRT from January 1983 to February 1996. Patient demographics, diagnosis, anesthesia techniques, monitoring, airway management, complications, and outcome were recorded for the patients requiring anesthesia. Results: One hundred twenty-three of the 512 children (24%) required 141 courses of EBRT with anesthesia. Anesthetized patients ranged in age from 20 days to 11 years (mean 2.6 ± 1.8 ). The frequency of a child receiving EBRT and requiring anesthesia by age cohort was: ≤ 1 year (96%), 1-2 years (93%), 2-3 years (80%), 3-4 years (51%), 4-5 years (36%), 5-6 years (13%), 6-7 years (11%), and 7-16 years (0.7%). Diagnoses included: primary CNS tumor (28%), retinoblastoma (27%), neuroblastoma (20%), acute leukemia (9%), rhabdomyosarcoma (6%), and Wilms' tumor (4%). Sixty-three percent of the patients had been exposed to chemotherapy prior to EBRT. The mean number of anesthesia sessions per patient was 22 ± 16. Seventy-eight percent of the treatment courses were once daily and 22% were twice daily. Anesthesia techniques included: short-acting barbiturate induction + inhalation maintenance (21%), inhalation only (20%), ketamine (19%), propofol only (12%), propofol induction + inhalation maintenance (7%), ketamine induction + inhalation maintenance (6%), ketamine or short-acting barbiturate induction + inhalation maintenance (6%). Monitoring techniques included: EKG (95%), O2 saturation (93%), fraction of inspired O2 (57%), and end-tidal CO2 (55%). Sixty-four percent of patients had central venous access. Eleven of the 74 children with a central line developed sepsis (15%): 6 of the 11 were anesthetized with propofol (55%), 4 with a short

  14. Image-Guidance for Stereotactic Body Radiation Therapy

    The term stereotactic body radiation therapy (SBRT) describes a recently introduced external beam radiation paradigm by which small lesions outside the brain are treated under stereotactic conditions, in a single or few fractions of high-dose radiation delivery. Similar to the treatment planning and delivery process for cranial radiosurgery, the emphasis is on sparing of adjacent normal tissues through the creation of steep dose gradients. Thus, advanced methods for assuring an accurate relationship between the target volume position and radiation beam geometry, immediately prior to radiation delivery, must be implemented. Such methods can employ imaging techniques such as planar (e.g., x-ray) or volumetric (e.g., computed tomography [CT]) approaches and are commonly summarized under the general term image-guided radiation therapy (IGRT). This review summarizes clinical experience with volumetric and ultrasound based image-guidance for SBRT. Additionally, challenges and potential limitations of pre-treatment image-guidance are presented and discussed

  15. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy

    Bray, Fleta N.; Simmons, Brian J.; Aaron H. Wolfson; Nouri, Keyvan

    2016-01-01

    Ionizing radiation is an important treatment modality for a variety of malignant conditions. However, development of radiation-induced skin changes is a significant adverse effect of radiation therapy (RT). Cutaneous repercussions of RT vary considerably in severity, course, and prognosis. When they do occur, cutaneous changes to RT are commonly graded as acute, consequential-late, or chronic. Acute reactions can have severe sequelae that impact quality of life as well as cancer treatment. Th...

  16. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    Miyazato, Tomonori; Yusa, Toshiko; Onaga, Tomohiro; Sugaya, Kimio; Koyama, Yuzo; Hatano, Tadashi; Ogawa, Yoshihide [Ryukyus Univ., Nishihara, Okinawa (Japan). Faculty of Medicine

    1998-05-01

    Radiation therapy has widely been used for cancers in the pelvis. Radiation cystitis, one of the late complications, presents often as hemorrhagic cystitis, which is refractory to the conventional therapy and may threaten the patient`s life. We used hyperbaric oxygen therapy on patients with radiation cystitis to test its potential benefit. Ten patients aged from 46 to 81 years with a mean of 62 years underwent one or more courses of hyperbaric oxygen therapy according to their symptoms, consisting of 20 sessions (3 to 5 sessions a week) at the Department of Hyperbaric Medicine, the University of the Ryukyus Hospital in the 9-year period from 1985 to 1994. They included 8 patients having a history of cervical cancer, one with external genital cancer and one with vaginal cancer. During the 75 min hyperbaric oxygen therapy patients received 100% oxygen at 2 absolute atmosphere pressure in the Multiplace Hyperbaric Chamber. Hematuria subsided and subjective symptoms including urinary frequency improved in seven patients. Cystoscopic findings including mucosal edema, redness, and capillary dilation were partially improved. The procedure subjectively and objectively palliated the 10 patients in a favorable manner. To date we have not armed any active procedure to control radiation-induced refractory hemorrhagic cystitis in terms of efficacy, invasiveness, and adverse effects. Therefore, in consideration of our clinical results, hyperbaric oxygen therapy appears to be useful for radiation cystitis. (author)

  17. Development of medical application methods using radiation. Radionuclide therapy

    Choi, Chang Woon; Lim, S. M.; Kim, E.H.; Woo, K. S.; Chung, W. S.; Lim, S. J.; Choi, T. H.; Hong, S. W.; Chung, H. Y.; No, W. C. [Korea Atomic Energy Research Institute. Korea Cancer Center Hospital, Seoul, (Korea, Republic of); Oh, B. H. [Seoul National University. Hospital, Seoul (Korea, Republic of); Hong, H. J. [Antibody Engineering Research Unit, Taejon (Korea, Republic of)

    1999-04-01

    In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: (1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. (2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. (3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology.

  18. Development of medical application methods using radiation. Radionuclide therapy

    In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: 1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. 2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. 3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology

  19. Radiation Therapy for Neovascular Age-related Macular Degeneration

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity

  20. Radiation Therapy for Neovascular Age-related Macular Degeneration

    Kishan, Amar U. [Harvard Medical School, Boston, Massachusetts (United States); Modjtahedi, Bobeck S.; Morse, Lawrence S. [Department of Ophthalmology and Vision Sciences, University of California, Davis, Sacramento, California (United States); Lee, Percy, E-mail: percylee@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California (United States)

    2013-03-01

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.

  1. Prototype demonstration of radiation therapy planning code system

    This is the final report of a one-year, Laboratory-Directed Research and Development project at the Los Alamos National Laboratory (LANL). Radiation therapy planning is the process by which a radiation oncologist plans a treatment protocol for a patient preparing to undergo radiation therapy. The objective is to develop a protocol that delivers sufficient radiation dose to the entire tumor volume, while minimizing dose to healthy tissue. Radiation therapy planning, as currently practiced in the field, suffers from inaccuracies made in modeling patient anatomy and radiation transport. This project investigated the ability to automatically model patient-specific, three-dimensional (3-D) geometries in advanced Los Alamos radiation transport codes (such as MCNP), and to efficiently generate accurate radiation dose profiles in these geometries via sophisticated physics modeling. Modem scientific visualization techniques were utilized. The long-term goal is that such a system could be used by a non-expert in a distributed computing environment to help plan the treatment protocol for any candidate radiation source. The improved accuracy offered by such a system promises increased efficacy and reduced costs for this important aspect of health care

  2. Optimizing proton therapy at the LBL medical accelerator

    Alonso, J.

    1992-03-01

    This Grant has marked the beginning of a multi-year study process expected to lead to design and construction of at least one, possibly several hospital-based proton therapy facilities in the United States.

  3. Optimizing proton therapy at the LBL medical accelerator. Final report

    Alonso, J.

    1992-03-01

    This Grant has marked the beginning of a multi-year study process expected to lead to design and construction of at least one, possibly several hospital-based proton therapy facilities in the United States.

  4. Reversible brachial plexopathy following primary radiation therapy for breast cancer

    Salner, A.L.; Botnick, L.E.; Herzog, A.G.; Goldstein, M.A.; Harris, J.R.; Levene, M.B.; Hellman, S.

    Reversible brachial plexopathy has occurred in very low incidence in patients with breast carcinoma treated definitively with radiation therapy. Of 565 patients treated between January 1968 and December 1979 with moderate doses of supervoltage radiation therapy (average axillary dose of 5000 rad in 5 weeks), eight patients (1.4%) developed the characteristic symptoms at a median time of 4.5 months after radiation therapy. This syndrome consists of paresthesias in all patients, with weakness and pain less commonly seen. The symptom complex differs from other previously described brachial plexus syndromes, including paralytic brachial neuritis, radiation-induced injury, and carcinoma. A possible relationship to adjuvant chemotherapy exists, though the etiology is not well-understood. The cases described demonstrate temporal clustering. Resolution is always seen.

  5. Dynamic optical modulation of an electron beam on a photocathode RF gun: Toward intensity-modulated radiation therapy (IMRT)

    In intensity-modulated radiation therapy (IMRT), the aim is to deliver reduced doses of radiation to normal tissue. As a step toward IMRT, we examined dynamic optical modulation of an electron beam produced by a photocathode RF gun. Images on photomasks were transferred onto a photocathode by relay imaging. The resulting beam was controlled by a remote mirror. The modulated electron beam maintained its shape on acceleration, had a fine spatial resolution, and could be moved dynamically by optical methods

  6. Dynamic optical modulation of an electron beam on a photocathode RF gun: Toward intensity-modulated radiation therapy (IMRT)

    Kondoh, Takafumi; Kashima, Hiroaki; Yang, Jinfeng; Yoshida, Yoichi; Tagawa, Seiichi

    2008-10-01

    In intensity-modulated radiation therapy (IMRT), the aim is to deliver reduced doses of radiation to normal tissue. As a step toward IMRT, we examined dynamic optical modulation of an electron beam produced by a photocathode RF gun. Images on photomasks were transferred onto a photocathode by relay imaging. The resulting beam was controlled by a remote mirror. The modulated electron beam maintained its shape on acceleration, had a fine spatial resolution, and could be moved dynamically by optical methods.

  7. Therapy palliative with 223Ra without special radiation protection measures?

    For nearly 2 years now as a therapy of the castration resistant prostata carcinoma a nuclide therapy with 223Ra-Dichloride (trade-mark Xofigo) is applied. Xofigo is applied by a medical specialist for nuclear medicine altogether 6 times in a monthly distance. The activity used in each case is according to the body weight (50 kBq/kg BW). This therapy is licensed by the supervisory authorities of the German federal countries as an ambulant therapy. Special radiation protection measures are only required when exceeding a given number of 17 patients per year as incorparation measurements.

  8. NEW DEVELOPMENTS IN RADIATION THERAPY FOR HEAD AND NECK CANCER: INTENSITY MODULATED RADIATION THERAPY AND HYPOXIA TARGETING

    Lee, Nancy Y.; Le, Quynh-Thu

    2008-01-01

    Intensity modulated radiation therapy (IMRT) has revolutionized radiation treatment for head and neck cancers (HNC). When compared to the traditional techniques, IMRT has the unique ability to minimize the dose delivered to normal tissues without compromising tumor coverage. As a result, side effects from high dose radiation have decreased and patient quality of life has improved. In addition to toxicity reduction, excellent clinical outcomes have been reported for IMRT. The first part of thi...

  9. Dose equivalent measurements in mixed and time varying radiation fields around high-energy accelerators

    Mayer, S

    2003-01-01

    Measurements of ambient dose equivalent in stray radiation fields behind the shielding of high-energy accelerators are a challenging task. Several radiation components (photons, neutrons, charged particles, muons, etc.), spanning a wide range of energies, contribute to the total dose equivalent. The radiation fields are produced by beam losses interacting with structural material during the acceleration or at the ejection to experimental areas or other accelerators. The particle beam is usually not continuous but separated in "bunches" or pulses, which further complicates dose measurements at high-energy accelerators. An ideal dosimeter for operational radiation protection should measure dose equivalent for any composition of radiation components in the entire energy range even when the field is strongly pulsed. The objective of this work was to find out if an ionisation chamber operated as a "recombination chamber" and a TEPC instrument using the variance-covariance method ("Sievert Instrument") are capable ...

  10. Alterations of nutritional status: impact of chemotherapy and radiation therapy

    The nutritional status of a cancer patient may be affected by the tumor, the chemotherapy and/or radiation therapy directed against the tumor, and by complications associated with that therapy. Chemotherpay-radiotherapy is not confined exclusively to malignant cell populations; thus, normal tissues may also be affected by the therapy and may contribute to specific nutritional problems. Impaired nutrition due to anorexia, mucositis, nausea, vomiting, and diarrhea may be dependent upon the specific chemotherapeutic agent, dose, or schedule utilized. Similar side effects from radiation therapy depend upon the dose, fractionation, and volume irradiated. When combined modality treatment is given the nutritional consequences may be magnified. Prospective, randomized clinical trials are underway to investigate the efficacy of nutritional support during chemotherapy-radiotherapy on tolerance to treatment, complications from treatment, and response rates to treatment. Preliminary results demonstrate that the administration of total parenteral nutrition is successful in maintaining weight during radiation therapy and chemotherapy, but that weight loss occurs after discontinuation of nutritional support. Thus, longterm evaluation is mandatory to learn the impact of nutritional support on survival, diease-free survival, and complication rates, as well as on the possible prevention of morbidity associated with aggressive chemotherapy-radiation therapy

  11. A new microwave EB accelerator for radiation processing

    Cracknell, P. J.

    1995-02-01

    A new high beam power microwave electron linear accelerator, LINTEC 1020, has been built and installed for the AEA, EBIS (Harwell) Limited medical sterilisation irradiation facility. LINTEC microwave electron beam accelerator designs are based upon travelling wave RF structures working at 1300 MHz, with beam powers from 10 to 45 k Watts at 5 to 12 MeV. The accelerator design, installation and operating details are described together with performance characteristics of alternative equipments.

  12. Radiation therapy for intracranial germ cell tumor

    Shimizu, Wakako; Takizawa, Yoshikazu; Yoshida, Hiroshi; Aruga, Moriyo; Arimizu, Noboru (Chiba Univ. (Japan). School of Medicine); Itami, Jun

    1993-05-01

    From 1974 through 1988, 27 patients with intracranial germ cell tumor underwent radiotherapy in Chiba University Hospital. Radiation field encompassed the whole neuroaxis in 19 patients, the local area in 5, and the whole brain in 3. Overall 5-year survival rate of all 27 patients was 88.9%. There was no significant difference in 5-year overall survival rate between the patients who were treated by the neuroaxis radiation and by the more limited fields. The most significant prognostic factor was pathology of the tumors. Germinoma and histology-unknown tumors which showed good response to irradiation have more favorable prognosis than embryonal carcinoma and choriocarcinoma. From our data, three possibilities emerged: (1) some germinomas might be controlled by localized radiation; (2) optimal dose might be 45[approx]50 Gy; (3) if histology-unknown tumor has good response to radiation at 20 Gy, the tumor can be treated by the same way as germinoma. (author).

  13. Controls and Beam Diagnostics for Therapy-Accelerators

    Eickhoff, H

    2000-01-01

    During the last four years GSI has developed a new procedure for cancer treatment by means of the intensity controlled rasterscan-method. This method includes active variations of beam parameters during the treatment session and the integration of 'on-line' PET monitoring. Starting in 1997 several patients have been successfully treated within this GSI experimental cancer treatment program; within this program about 350 patients shall be treated in the next 5 years. The developments and experiences of this program accompanied by intensive discussions with the medical community led to a proposal for a hospital based light ion accelerator facility for the clinic in Heidelberg. An essential part for patients treatments is the measurement of the beam properties within acceptance and constancy tests and especially for the rasterscan method during the treatment sessions. The presented description of the accelerator controls and beam diagnostic devices mainly covers the requests for the active scanning method, which...

  14. Movie prediction of lung tumor for precise chasing radiation therapy

    In recent years, precision for radiation therapy is a major challenge in the field of cancer treatment. When it comes to a moving organ like lungs, limiting the radiation to the target and sparing the surrounding healthy tissue is always a concern. It can induce the limit in the accuracy of area irradiated during lung cancer radiation therapy. Many methods have been introduced to compensate the motion in order to reduce the effect of radiation to healthy tissue due to respiratory motion. The motion of lung along with the tumor makes it very difficult to spare the healthy tissue during radiation therapy. The fear of this unintended damage to the neighboring tissue often limits the dose that can be applied to the tumor. The purpose of this research is the prediction of future motion images for the improvement of tumor tracking method. We predict the motion images by using principal component analysis (PCA) and multi-channel singular spectral analysis (MSSA) method. Time series x-ray images are used as training images. The motion images were successfully predicted and verified using the developed algorithm. The real time implementation of this method in future is believed to be significant for higher level of real time tumor tracking during radiation therapy. (author)

  15. Extended-field radiation therapy for carcinoma of the cervix

    The survival of cervical carcinoma patients with paraaortic/high common iliac nodal metastases was evaluated by retrospective chart review during a 13-year interval. Thirty-three patients with cervical carcinoma and surgically documented nodal metastases received primary, extended-field radiation therapy. Overall 2-year and 5-year actuarial survival rates after diagnosis were 37% and 31%, respectively. Survival was analyzed in terms of the variables patient age, clinical stage, tumor histologic type, the presence of enlarged paraaortic/high common iliac lymph nodes, the extent of nodal involvement (microscopic versus macroscopic), the presence of intraperitoneal disease, and whether intracavitary brachytherapy was administered. The use of intracavitary radiation therapy was associated with improved local control and survival (P = 0.017). None of the other variables were statistically related to patient survival. Twenty-two of the patients died of cervical cancer and five are surviving without evidence of cancer. Four patients died of intercurrent disease. Two patients developed bowel-related radiation complications; both patients received chemotherapy concurrent with the radiation therapy. One of the two patients died of radiation enteritis. The use of extended-field radiation therapy does benefit a small group of patients and may result in extended patient survival

  16. Technical assessment of the Loma Linda University proton therapy accelerator

    1989-10-01

    In April 1986, officials of Loma Linda University requested that Fermilab design and construct a 250 MeV proton synchrotron for radiotherapy, to be located at the Loma Linda University Medical Center. In June 1986 the project, having received all necessary approvals, commenced. In order to meet a desirable schedule providing for operation in early 1990, it was decided to erect such parts of the accelerator as were complete at Fermilab and conduct a precommissioning activity prior to the completion of the building at Loma Linda which will house the final radiotherapy facility. It was hoped that approximately one year would be saved by the precommissioning, and that important information would be obtained about the system so that improvements could be made during installation at Loma Linda. This report contains an analysis by Fermilab staff members of the information gained in the precommissioning activity and makes recommendations about steps to be taken to enhance the performance of the proton synchrotron at Loma Linda. In the design of the accelerator, effort was made to employ commercially available components, or to industrialize the products developed so that later versions of the accelerator could be produced industrially. The magnets could only be fabricated at Fermilab if the schedule was to be met, but efforts were made to transfer that technology to industry. Originally, it was planned to use a 1.7 MeV RFQ fabricated at the Lawrence Berkeley Laboratory as injector, but LBL would have found it difficult to meet the project schedule. After consideration of other options, for example a 3.4 MeV tandem accelerator, a supplier (AccSys Inc.) qualified itself to provide a 2 MeV RFQ on a schedule well matched to the project schedule. This choice was made, but a separate supplier was selected to develop and provide the 425 MHz power amplifier for the RFQ.

  17. Technical assessment of the Loma Linda University proton therapy accelerator

    In April 1986, officials of Loma Linda University requested that Fermilab design and construct a 250 MeV proton synchrotron for radiotherapy, to be located at the Loma Linda University Medical Center. In June 1986 the project, having received all necessary approvals, commenced. In order to meet a desirable schedule providing for operation in early 1990, it was decided to erect such parts of the accelerator as were complete at Fermilab and conduct a precommissioning activity prior to the completion of the building at Loma Linda which will house the final radiotherapy facility. It was hoped that approximately one year would be saved by the precommissioning, and that important information would be obtained about the system so that improvements could be made during installation at Loma Linda. This report contains an analysis by Fermilab staff members of the information gained in the precommissioning activity and makes recommendations about steps to be taken to enhance the performance of the proton synchrotron at Loma Linda. In the design of the accelerator, effort was made to employ commercially available components, or to industrialize the products developed so that later versions of the accelerator could be produced industrially. The magnets could only be fabricated at Fermilab if the schedule was to be met, but efforts were made to transfer that technology to industry. Originally, it was planned to use a 1.7 MeV RFQ fabricated at the Lawrence Berkeley Laboratory as injector, but LBL would have found it difficult to meet the project schedule. After consideration of other options, for example a 3.4 MeV tandem accelerator, a supplier (AccSys Inc.) qualified itself to provide a 2 MeV RFQ on a schedule well matched to the project schedule. This choice was made, but a separate supplier was selected to develop and provide the 425 MHz power amplifier for the RFQ

  18. Physical basis of heavy ion radiation therapy

    Physical foundation of a heavy ion radio-therapy was discussed, especially on a designing a spread Bragg peak with a ridge filter. A large radiobiological effectiveness will be positively utilized in the heavy ion radio-therapy. The biological effectiveness will be different depending on the depth in human body. This fact gives us difficult problems when we aim to kill uniformly the target cells in human body. As a first step to solve these problems, biological effectiveness of a mixed beam using monoenergetic low and high LET beams was examined and try to understand the results by the amorphous image of the track structure of the heavy ions. A research on a microscopic pattern of energy deposition will be important to solve biophysical problem in heavy ion radio-therapy. (author)

  19. Rapid growth of microscopic rectal cancer as a determinant of response to preoperative radiation therapy

    Purpose: To quantify the dose-time fractionation factors in preoperative radiation therapy for microscopic pelvic deposits of rectal cancer. This provides a biologic basis for understanding and improving the results of adjuvant therapies for this disease. Methods: The reduction in incidence of pelvic relapses as a function of radiation dose and overall treatment time was determined from the literature. The displacement of dose-response curves to higher doses reflects the growth during radiation treatment of subclinical pelvic deposits which are beyond the future surgical margins. Results: Dose-response curves are steep if the effect of overall duration of radiation therapy is accounted for. The time-related displacement of these steep dose-response curves is consistent with a median doubling time for malignant clonogenic cells of about 4 or 5 days, much faster than the growth rate of the average primary tumor at diagnosis. This rapid growth is evident within the first few days of irradiation, implying that the natural growth rate of these microscopic deposits if fast, and/or that an acceleration of growth follows initiation of radiation injury with a very short lag time. Conclusion: Subclinical pelvic deposits of rectal cancer grow rapidly during preoperative radiation therapy with an adverse influence on the rate of pelvic tumor control from protracting the duration of adjuvant treatment. Low doses only offer clinically relevant reduction in risk of pelvic relapses if the overall radiation treatment time is short. For a given overall treatment duration there is a relatively steep dose-response curve, predicting that significant improvements in tumor control are possible

  20. Generation of heavy ion beams using femtosecond laser pulses in the target normal sheath acceleration and radiation pressure acceleration regimes

    Petrov, G. M.; McGuffey, C.; Thomas, A. G. R.; Krushelnick, K.; Beg, F. N.

    2016-06-01

    Theoretical study of heavy ion acceleration from sub-micron gold foils irradiated by a short pulse laser is presented. Using two dimensional particle-in-cell simulations, the time history of the laser pulse is examined in order to get insight into the laser energy deposition and ion acceleration process. For laser pulses with intensity 3 × 10 21 W / cm 2 , duration 32 fs, focal spot size 5 μm, and energy 27 J, the calculated reflection, transmission, and coupling coefficients from a 20 nm foil are 80%, 5%, and 15%, respectively. The conversion efficiency into gold ions is 8%. Two highly collimated counter-propagating ion beams have been identified. The forward accelerated gold ions have average and maximum charge-to-mass ratio of 0.25 and 0.3, respectively, maximum normalized energy 25 MeV/nucleon, and flux 2 × 10 11 ions / sr . An analytical model was used to determine a range of foil thicknesses suitable for acceleration of gold ions in the radiation pressure acceleration regime and the onset of the target normal sheath acceleration regime. The numerical simulations and analytical model point to at least four technical challenges hindering the heavy ion acceleration: low charge-to-mass ratio, limited number of ions amenable to acceleration, delayed acceleration, and high reflectivity of the plasma. Finally, a regime suitable for heavy ion acceleration has been identified in an alternative approach by analyzing the energy absorption and distribution among participating species and scaling of conversion efficiency, maximum energy, and flux with laser intensity.