WorldWideScience

Sample records for biological image-adapted radiotherapy

  1. Dynamic contrast enhanced magnetic resonance imaging of bladder cancer and implications for biological image-adapted radiotherapy

    International Nuclear Information System (INIS)

    Purpose. To assess the role of image parameters derived from dynamic contrast enhanced magnetic resonance imaging (DCEMRI) in bladder cancer staging, and to investigate the potential use of such parameter images in biological image-adapted radiotherapy (RT). Materials and methods. High-resolution volumetric interpolated breath-hold (VIBE) DCEMRI of 26 patients diagnosed with bladder cancer was performed. DCEMRI parameters derived from tumor and muscle contrast uptake curves were extracted and subjected to correlation analysis with tumor volume as well as clinical, pathological, histological and T2-weighted MR tumor stage. For parameters showing a significant correlation with tumor stage, 3D malignancy maps were generated. As an initial step towards delivery of biologically adapted intensity modulated radiotherapy (IMRT) it was hypothesized that the malignancy map could be used as a RT dose prescription map. Simulating IMRT delivery with multi-leaf collimators (MLCs), idealized dose distributions, constituted by dose cubes, were adapted to the prescription map. The size of the dose cubes were varied to mimic MLCs of varying leaf width. The difference between the adapted and prescribed dose distributions was quantified by the root mean square deviation (RMSD). Results. No significant relationships were found between tumor volume and extracted DCEMRI parameters. The normalized area between tumor and muscle contrast uptake curves (nABC) evaluated from 0-180 seconds (nABC180) and 0-480s (nABC480) correlated significantly with tumor stage (p=0.047 and p=0.035, respectively). Dose prescription maps for 10 patients were generated from the nABC480. The RMSD between the prescribed and adapted dose distribution decreased with decreasing size of the dose cubes. Large interpatient variations in the RMSD and in the dependence of the RMSD on different dose cube sizes were found. Conclusions. The nABC180 and nABC480 may provide added value in staging of bladder cancer. High

  2. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R

    2014-01-01

    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  3. Biological planning of treatment that combines local external radiotherapy with molecular systemic radiotherapy

    International Nuclear Information System (INIS)

    The combination of different therapy modalities for cancer treatment has been often used in order to enhance the outcomes. Therapeutic schemes that combines external beam irradiation ('eLRT') and systemic molecular radiotherapy (sMRT) could be an alternative in those patients with multiple lesions or when the constrains for OARs will difficult the planning. The formulation could be used for biological evaluation of prescriptions in treatment that combines external beam radiotherapy with systemic molecular radiotherapy. The advantage of ccRT v.s. scRT depends of treatment prescription (administered activity and dose fractioning) and tissue response. Treatment planning and optimization it is possible to be done in those cases where highly conformed dose boost using systemic molecular radiotherapy could be an option (author)

  4. Biological basis for modifying radiotherapy and chemotherapy

    International Nuclear Information System (INIS)

    Standard radiotherapy is administered as a series of equal doses usually 5/week for several weeks, a process termed fractionation. Each equal dose 'fraction' kills the same proportion of cells. A common daily dose is 200 centiGray (previous terminology: 200 rad) which reduces tumor cell survival to about 50%. A similar dose administered the next day will further reduce survival by 50%, that is to 25% of the original population. This equal proportionate effect results in a logarithmic decline in total cell number with increase in number of dose fractions. Breaking the total dose into a series of dose fractions amplifies therapeutic differential between normal tissues and tumors for several reasons; 4 R's: repair of cellular injury, repopulation by surviving cells, redistribution within the division cycle, reoxygenation of the tumor. Additional modifications of fractionation aim at increasing the advantage already gained from standard fractionation. (author). 4 refs

  5. Evaluation of conformal radiotherapy techniques through physics and biologic criteria

    International Nuclear Information System (INIS)

    In the fight against cancer, different irradiation techniques have been developed based on technological advances and aiming to optimize the elimination of tumor cells with the lowest damage to healthy tissues. The radiotherapy planning goal is to establish irradiation technical parameters in order to achieve the prescribed dose distribution over the treatment volumes. While dose prescription is based on radiosensitivity of the irradiated tissues, the physical calculations on treatment planning take into account dosimetric parameters related to the radiation beam and the physical characteristics of the irradiated tissues. To incorporate tissue's radiosensitivity into radiotherapy planning calculations can help particularize treatments and establish criteria to compare and elect radiation techniques, contributing to the tumor control and the success of the treatment. Accordingly, biological models of cellular response to radiation have to be well established. This work aimed to study the applicability of using biological models in radiotherapy planning calculations to aid evaluating radiotherapy techniques. Tumor control probability (TCP) was studied for two formulations of the linear-quadratic model, with and without repopulation, as a function of planning parameters, as dose per fraction, and of radiobiological parameters, as the α/β ratio. Besides, the usage of biological criteria to compare radiotherapy techniques was tested using a prostate planning simulated with Monte Carlo code PENELOPE. Afterwards, prostate planning for five patients from the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, USP, using three different techniques were compared using the tumor control probability. In that order, dose matrices from the XiO treatment planning system were converted to TCP distributions and TCP-volume histograms. The studies performed allow the conclusions that radiobiological parameters can significantly influence tumor control

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

    International Nuclear Information System (INIS)

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

  7. Biological effects and equivalent doses in radiotherapy: a software solution

    CERN Document Server

    Voyant, Cyril; Roustit, Rudy; Biffi, Katia; Marcovici, Celine Lantieri

    2013-01-01

    The limits of TDF (time, dose, and fractionation) and linear quadratic models have been known for a long time. Medical physicists and physicians are required to provide fast and reliable interpretations regarding the delivered doses or any future prescriptions relating to treatment changes. We therefore propose a calculation interface under the GNU license to be used for equivalent doses, biological doses, and normal tumor complication probability (Lyman model). The methodology used draws from several sources: the linear-quadratic-linear model of Astrahan, the repopulation effects of Dale, and the prediction of multi-fractionated treatments of Thames. The results are obtained from an algorithm that minimizes an ad-hoc cost function, and then compared to the equivalent dose computed using standard calculators in seven French radiotherapy centers.

  8. Biological optimization of heterogeneous dose distributions in systemic radiotherapy

    International Nuclear Information System (INIS)

    The standard computational method developed for internal radiation dosimetry is the MIRD (medical internal radiation dose) formalism, based on the assumption that tumor control is given by uniform dose and activity distributions. In modern systemic radiotherapy, however, the need for full 3D dose calculations that take into account the heterogeneous distribution of activity in the patient is now understood. When information on nonuniform distribution of activity becomes available from functional imaging, a more patient specific 3D dosimetry can be performed. Application of radiobiological models can be useful to correlate the calculated heterogeneous dose distributions to the current knowledge on tumor control probability of a homogeneous dose distribution. Our contribution to this field is the introduction of a parameter, the F factor, already used by our group in studying external beam radiotherapy treatments. This parameter allows one to write a simplified expression for tumor control probability (TCP) based on the standard linear quadratic (LQ) model and Poisson statistics. The LQ model was extended to include different treatment regimes involving source decay, incorporating the repair 'μ' of sublethal radiation damage, the relative biological effectiveness and the effective 'waste' of dose delivered when repopulation occurs. The sensitivity of the F factor against radiobiological parameters (α,β,μ) and the influence of the dose volume distribution was evaluated. Some test examples for 131I and 90Y labeled pharmaceuticals are described to further explain the properties of the F factor and its potential applications. To demonstrate dosimetric feasibility and advantages of the proposed F factor formalism in systemic radiotherapy, we have performed a retrospective planning study on selected patient case. F factor formalism helps to assess the total activity to be administered to the patient taking into account the heterogeneity in activity uptake and dose

  9. Biologically Weighted Quantities in Radiotherapy: an EMRP Joint Research Project

    Directory of Open Access Journals (Sweden)

    Rabus Hans

    2014-01-01

    Full Text Available Funded within the European Metrology Research Programme (EMRP [1], the joint research project “Biologically weighted quantities in radiotherapy” (BioQuaRT [2] aims to develop measurement and simulation techniques for determining the physical properties of ionising particle tracks on different length scales (about 2 nm to 10 μm, and to investigate the correlation of these track structure characteristics with the biological effects of radiation at the cellular level. Work package 1 develops micro-calorimeter prototypes for the direct measurement of lineal energy and will characterise their response for different ion beams by experiment and modelling. Work package 2 develops techniques to measure particle track structure on different length scales in the nanometre range as well as a measurement device integrating a silicon microdosimeter and a nanodosimeter. Work package 3 investigates the indirect effects of radiation based on probes for quantifying particular radical and reactive oxygen species (ROS. Work package 4 focuses on the biological aspects of radiation damage and will produce data on initial DNA damage and late effects for radiotherapy beams of different qualities. Work package 5 provides evaluated data sets of DNA cross-sections and develops a multi-scale model to address microscopic and nanometric track structure properties. The project consortium includes three linked researchers holding so-called Researcher Excellence Grants, who carry out ancillary investigations such as developing and benchmarking a new biophysical model for induction of early radiation damage and developing methods for the translation of quantities derived from particle track structure to clinical applications in ion beam therapy.

  10. Physical and biological basis of hadron radiotherapy. Book of abstracts

    International Nuclear Information System (INIS)

    The Workshop was a satellite event of the 14th International Congress of Radiation Research (ICRR-2011). It was held in Cracow, Poland, on the 2 and 3 September 2011, at the Collegium Novum of the Jagiellonian University. The Workshop organized, jointly by the Institute of Nuclear Physics of the Polish Academy of Sciences and the Polish Radiation Research Society, would provide its participants with an opportunity to discuss current topics in proton and carbon radiotherapy, clinical aspects of ion radiotherapy, ion beam dosimetry, unwanted patient exposure, radiobiology for ion radiotherapy and other relevant subjects. Book of Abstracts contains abstracts of 33 oral presentations and 12 posters.

  11. Biological modeling of gold nanoparticle enhanced radiotherapy for proton therapy

    International Nuclear Information System (INIS)

    Gold nanoparticles (GNPs) have shown potential as a radiosensitizer for radiation therapy using photon beams. Recently, experimental studies have been carried out using proton beams showing the GNP enhanced responses in proton therapy. In this work, we established a biological model to investigate the change in survival of irradiated cells due to the radiosensitizing effect of gold nanoparticles. Results for proton, megavoltage (MV) photon and kilovoltage (kV) photon beams are compared. For each particle source, we assessed various treatment depths, GNP cellular uptakes and sizes. We showed that kilovoltage photons caused the highest enhancement due to the high interaction probability between GNPs and kV photons. The cell survival fraction can be significantly reduced for both proton and MV photon irradiations if GNPs accumulate in the cell. For instance, the sensitizer enhancement ratio (SER) is 1.33 for protons in the middle of a spread out Bragg peak for 1 µM of internalized 50 nm GNPs. If the GNPs can all be internalized into the cell nucleus, the SER for proton therapy increases from 1.33 to 1.81. The results also show that for the same mass of GNPs in the cells, one can expect the greatest sensitization by smaller GNPs, i.e. a SER of 1.33 for 1 µM of internalized 50 nm GNPs and a SER of 3.98 for the same mass of 2 nm GNPs. We concluded that if the GNPs cannot be internalized into the cytoplasm, no GNP enhancement will be observed for proton treatment. Meanwhile, proton radiotherapy can potentially be enhanced with GNPs if they can be internalized into cells, and especially the cell nucleus. (paper)

  12. Radiotherapy

    International Nuclear Information System (INIS)

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

  13. Biological modelling of fuzzy target volumes in 3D radiotherapy

    International Nuclear Information System (INIS)

    Purpose/Objective: The outcome of each radiotherapy depends critically on the optimal choice of the target volume. The goal of the radiotherapist is to include all tumor spread at the same time as saving as much healthy tissue as possible. Even when the information of all imaging modalities is combined, the diagnostic techniques are not sensitive and specific enough to visualize all microscopic tumor cell spread. Due to this lack of information there is room for different interpretations concerning the extend of the target volume, leading to a fuzzy target volume. The aim of this work is to develop a model to score different target volume boundaries within the region of diagnostic uncertainty in terms of tumor control probability (TCP) and normal tissue complication probabilities (NTCP). Materials and Methods: In order to assess the region of diagnostic uncertainty, the radiotherapist defines interactively a minimal planning target volume that absolutely must be irradiated according to the diagnostic information available and a maximal planning target volume outside which no tumor cell spread is expected. For the NTCP calculation we use the Lyman 4 parameter model to estimate the response of an organ at risk to a uniform partial volume irradiation. The TCP calculation is based on the Poisson model of cell killing. The TCP estimation depends not only on volume, dose, clonogenic cell density and the α parameter of the linear quadratic model but also on the probability to find clonogenic cells in the considered volume. Inside the minimal PTV this probability is 1, outside the maximal PTV it is 0. Therefore all voxels inside the minimal PTV are assigned the value of 1 with respect to the target volume, all voxels outside the maximal PTV the value of 0. For voxels in the region of uncertainty in between, a 3D linear interpolation is performed. Here we assume the probability to follow the interpolated values. Starting with the minimal PTV, the expected gain in TCP and

  14. Radiation protection and secondary cancer prevention using biological radioprotectors in radiotherapy

    Directory of Open Access Journals (Sweden)

    Hamid Abdollahi

    2015-09-01

    Full Text Available Radiotherapy is the feasible treatment approach for many malignant diseases and cancers. New radiotherapy techniques such as ion therapy, stereotactic radiosurgery and intensity modulated radiation therapy deliver higher low dose radiation to large volume of normal tissues and are in debating as more secondary cancers inducers. A secondary cancer after radiotherapy is an important issue that reduces treatment efficiency and should be decreased. Radioprotective compounds are of importance in clinical radiation therapy for saving normal tissues. In the present study, we are so interest to introduce, suggest and review the application of biological radioprotectors in radiotherapy. We propose probiotics, prebiotics, gas, vitamin and nanoparticle producing microorganisms as new biological systems based radioprotectors to protect normal tissues. Also, we reviewed the main biological pathways, molecules and also radioadaptive response that act as radioprotectors. In this review we tried to address the secondary cancer induction by radiotherapy and also main biological radiation protection approaches, although there is a wealth of data in this subject.  

  15. Biological dose representation for carbon-ion radiotherapy of unconventional fractionation

    OpenAIRE

    Kanematsu, Nobuyuki; Inaniwa, Taku

    2016-01-01

    In carbon-ion radiotherapy, single-beam delivery each day in alternate directions has been commonly practiced for operational efficiency, taking advantage of the Bragg peak and the relative biological effectiveness (RBE) for uniform dose conformation to a tumor. The treatment plans are usually evaluated with total RBE-weighted dose, which is however deficient in relevance to the biological effect in the linear-quadratic model due to its quadratic-dose term, or the dose-fractionation effect. I...

  16. Radiotherapy

    International Nuclear Information System (INIS)

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

  17. Molecular PET imaging for biology-guided adaptive radiotherapy of head and neck cancer

    International Nuclear Information System (INIS)

    Integration of molecular imaging PET techniques into therapy selection strategies and radiation treatment planning for head and neck squamous cell carcinoma (HNSCC) can serve several purposes. First, pre-treatment assessments can steer decisions about radiotherapy modifications or combinations with other modalities. Second, biology-based objective functions can be introduced to the radiation treatment planning process by co-registration of molecular imaging with planning computed tomography (CT) scans. Thus, customized heterogeneous dose distributions can be generated with escalated doses to tumor areas where radiotherapy resistance mechanisms are most prevalent. Third, monitoring of temporal and spatial variations in these radiotherapy resistance mechanisms early during the course of treatment can discriminate responders from non-responders. With such information available shortly after the start of treatment, modifications can be implemented or the radiation treatment plan can be adapted tailing the biological response pattern. Currently, these strategies are in various phases of clinical testing, mostly in single-center studies. Further validation in multicenter set-up is needed. Ultimately, this should result in availability for routine clinical practice requiring stable production and accessibility of tracers, reproducibility and standardization of imaging and analysis methods, as well as general availability of knowledge and expertise. Small studies employing adaptive radiotherapy based on functional dynamics and early response mechanisms demonstrate promising results. In this context, we focus this review on the widely used PET tracer 18F-FDG and PET tracers depicting hypoxia and proliferation; two well-known radiation resistance mechanisms

  18. Biological systems: from water radiolysis to carbon ion radiotherapy

    Science.gov (United States)

    Beuve, Michael; Moreau, Jean-Michel; Rodriguez, Claire; Testa, Etienne

    2015-07-01

    Hadron therapy is an innovative cancer treatment method based on the acceleration of light ions at high energy. In addition to their interesting profile of dose deposition, which ensures accurate targeting of localized tumors, carbon ions offer biological properties that lead to an efficient treatment for radio- and chemo-resistant tumors and to provide a boost for tumors in hypoxia. This paper is a short review of the progress in theoretical, experimental, fundamental and applied research, aiming at understanding the origin of the biological benefits of light ions better. As a limit of such a vast and multidisciplinary domain, this review adopts the point of view of the physicists, leaning on results obtained in connection with CIMAP's IRRABAT platform.

  19. Radiotherapy

    International Nuclear Information System (INIS)

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

  20. Influence of TACE combined with radioactive seed radiotherapy on primary liver cancer patients’ malignant biological indicators

    Institute of Scientific and Technical Information of China (English)

    Yao Liu; Yu Wang; Guang-Yan Lei; Xiao-Hong Yan; Qiao Yang; Hai-Ping Zhu; Yi Geng

    2016-01-01

    Objective:To analyze the influence of TACE combined with radioactive seed radiotherapy on primary liver cancer patients’ malignant biological indicators.Methods:A total of 112 cases of primary liver cancer patients who received treatment in our hospital, Xijing Hospital and Tumor Hospital of Shaanxi Province were chosen as research subjects and divided into control group (TACE therapy alone) with 63 cases in it and observation group (TACE combined with radioactive seed radiotherapy) with 49 cases according to different treatment, and then the levels of malignant biological indicators after 2 months of treatment were compared between two groups.Results:Serum VEGF, FGF and MMP levels of observation group after treatment were significantly lower than those of control group; serum AFP-L3, GP73, Sb7-H3, AFU and CatS levels were significantly lower than those of control group; serum ICAM-1, ESM-1 and uPA levels were lower than those of control group.Conclusion: TACE combined with radioactive seed radiotherapy can effectively reduce primary liver cancer patients’ serum malignant biological indicator levels, decrease the degree of malignancy of cancer cells and slow disease progression, and is an ideal treatment.

  1. Biological Optimization in Volumetric Modulated Arc Radiotherapy for Prostate Carcinoma

    International Nuclear Information System (INIS)

    Purpose: To investigate the potential benefits achievable with biological optimization for modulated volumetric arc (VMAT) treatments of prostate carcinoma. Methods and Materials: Fifteen prostate patient plans were studied retrospectively. For each case, planning target volume, rectum, and bladder were considered. Three optimization schemes were used: dose–volume histogram (DVH) based, generalized equivalent uniform dose (gEUD) based, and mixed DVH/gEUD based. For each scheme, a single or dual 6-MV, 356° VMAT arc was used. The plans were optimized with Pinnacle3 (v. 9.0 beta) treatment planning system. For each patient, the optimized dose distributions were normalized to deliver the same prescription dose. The quality of the plans was evaluated by dose indices (DIs) and gEUDs for rectum and bladder. The tallied DIs were D1%, D15%, D25%, and D40%, and the tallied gEUDs were for a values of 1 and 6. Statistical tests were used to quantify the magnitude and the significance of the observed differences. Monitor units and treatment times for each optimization scheme were also assessed. Results: All optimization schemes generated clinically acceptable plans. The statistical tests indicated that biological optimization yielded increased organs-at-risk sparing, ranging from ∼1% to more than ∼27% depending on the tallied DI, gEUD, and anatomical structure. The increased sparing was at the expense of longer treatment times and increased number of monitor units. Conclusions: Biological optimization can significantly increase the organs-at-risk sparing in VMAT optimization for prostate carcinoma. In some particular cases, however, the DVH-based optimization resulted in superior treatment plans.

  2. Radiation biology: Major advances and perspectives for radiotherapy

    International Nuclear Information System (INIS)

    At the beginning of the 21. century, radiation biology is at a major turning point in its history. It must meet the expectations of the radiation oncologists, radiologists and the general public, but its purpose remains the same: to understand the molecular, cellular and tissue levels of lethal and carcinogenic effects of ionizing radiation in order to better protect healthy tissues and to develop treatments more effective against tumours. Four major aspects of radiobiology that marked this decade will be discussed: technological developments, the importance of signalling and repair of radiation-induced deoxyribonucleic acid (DNA) damage, the impact of individual factor in the response to radiation and the contribution of radiobiology to better choose innovative therapies such as proton-therapy or stereotactic body radiation therapy (SBRT). A translational radiobiology should emerge with the help of radiotherapists and radiation physicists and by facilitating access to the new radio and/or chemotherapy modalities. (authors)

  3. (RadioBiological Optimization of External-Beam Radiotherapy

    Directory of Open Access Journals (Sweden)

    Alan E. Nahum

    2012-01-01

    Full Text Available “Biological optimization” (BIOP means planning treatments using (radiobiological criteria and models, that is, tumour control probability and normal-tissue complication probability. Four different levels of BIOP are identified: Level I is “isotoxic” individualization of prescription dose at fixed fraction number. is varied to keep the NTCP of the organ at risk constant. Significant improvements in local control are expected for non-small-cell lung tumours. Level II involves the determination of an individualized isotoxic combination of and fractionation scheme. This approach is appropriate for “parallel” OARs (lung, parotids. Examples are given using our BioSuite software. Hypofractionated SABR for early-stage NSCLC is effectively Level-II BIOP. Level-III BIOP uses radiobiological functions as part of the inverse planning of IMRT, for example, maximizing TCP whilst not exceeding a given NTCP. This results in non-uniform target doses. The NTCP model parameters (reflecting tissue “architecture” drive the optimizer to emphasize different regions of the DVH, for example, penalising high doses for quasi-serial OARs such as rectum. Level-IV BIOP adds functional imaging information, for example, hypoxia or clonogen location, to Level III; examples are given of our prostate “dose painting” protocol, BioProp. The limitations of and uncertainties inherent in the radiobiological models are emphasized.

  4. Relative biological effectiveness (RBE) of proton beams in radiotherapy

    International Nuclear Information System (INIS)

    Treatment planning in proton therapy uses a generic value for the Relative Biological Efficiency (RBE) of 1.1 relative to 60Co gamma-rays throughout the Spread Out Bragg Peak (SOBP). We have studied the variation of the RBE at three positions in the SOBP of the 76 and 201 MeV proton beams used for cancer treatment at the Institut Curie Proton Therapy in Orsay (ICPO) in two human tumor cell lines using clonogenic cell death and the incidence of DNA double-strand breaks (DSB) as measured by pulse-field gel electrophoresis without and with endonuclease treatment to reveal clustered lesions as endpoints.The RBE for induced cell killing by the 76 MeV beam increased with depth in the SOBP. However for the 201 MeV protons it was close to that for 137Cs gamma-rays and did not vary significantly. The incidence of DSBs and clustered lesions was higher for protons than for 137Cs g-rays, but did not depend on the proton energy or the position in the SOBP. In the second part of our work, we have shown using cell clones made deficient for known repair genes by stable or transient shRNA transfection, that the D-NHEJ pathway determine the response to protons. The response of DNA damages created in the distal part of the 76 MeV SOBP suggests that those damages belong to the class of DNA 'complex lesions' (LMDS). It also appears that the particle fluence is a major determinant of the outcome of treatment in the distal part of the SOBP. (author)

  5. The biological approach to the radiotherapy of the oral cancers of South India

    International Nuclear Information System (INIS)

    Two-thirds of all cancers in South India are squamous cell carcinomas, of which 78% to 93% are late cases requiring radiotherapy. Oral cancers, which constitute the majority of these, provided an excellent clinical model for studies in radiotherapeutic biology. Their characteristics made them ideally suited for our clinical trials. The paper reviews the special biology of these lesions, the factors involved in their radiation non-response, the therapeutic postulations that suggested themselves, the implementation of these therapeutic protocols and the mixed story of failure and success that has marked the two decades of these studies. It discovers the fact that radiation response is not just a factor of tumor extent but involves several biological subleties in both tumor and its host environment. It also discusses possible future approaches to bridge a gap of about 30% failure in these lesions, especially in the context of a poor economy. (orig.)

  6. Metastatic renal cell carcinoma: can it be palliated with radiotherapy? Do higher biologically effective doses help?

    International Nuclear Information System (INIS)

    BACKGROUND: Renal cell carcinoma (RCC) has traditionally been regarded as a 'radioresistant cancer'. Yet controversy exists as to whether dose escalation can overcome the inherent resistance of such tumors when they metastasize. Using a Tumor Dose Factor (TDF) model, Onuffrey et al. (IJROB 11:2007, 1985) showed that TDF >70 was predictive of higher palliative response rates. In contrast, Halperin et al (Cancer 51:614, 1983) could not establish a correlation between TDF equivalent dose and frequency of palliative response. Since that time, the linear quadratic model has emerged as an alternative paradigm for biologically effective dose (BED). The current project was undertaken to determine the ability of radiotherapy to palliate focally metastatic RCC and to assess whether the delivery of higher biologically effective dose was more likely to bring about complete palliative response (CR). METHODS: Between 1966 and 1995, 107 patients with renal cell metastases at 150 sites were irradiated with palliative intent. Sites irradiated included bone (n=89), soft tissue (n=16), brain (n=20), spinal cord (n=9), and pulmonary (n=16). To determine dose effectiveness, the biological effective dose (BED) was calculated according to the following formula Gy10 = Total Dose (1 + fractional dose/α-β) using an α-β of 10. The above table presents univariate comparisons. For the entire series, 94% of patients derived a palliative response after treatment with irradiation. The median duration of palliation was 4 months (range, 2-80 months). With respect to overall response, only patients with metastases to the spinal cord were significantly less likely to derive palliation in multivariate analysis (p70) and the rate of CR (p=0.03). When entered as a dichotomous variable (e.g., relative to 39 Gy 10) increasing biologically effective dose was not associated with an increased rate of complete palliation; however, when entered as a continuous variable, increasing BED was strongly

  7. Automated biological target volume delineation for radiotherapy treatment planning using FDG-PET/CT

    International Nuclear Information System (INIS)

    This study compared manually delineated gross tumour volume (GTV) and automatically generated biological tumour volume (BTV) based on fluoro-deoxy-glucose (FDG) positron emission tomography (PET)/CT to assess the robustness of predefined PET algorithms for radiotherapy (RT) planning in routine clinical practice. RT-planning data from 20 consecutive patients (lung- (40%), oesophageal- (25%), gynaecological- (25%) and colorectal (10%) cancer) who had undergone FDG-PET/CT planning between 08/2010 and 09/2011 were retrospectively analysed, five of them underwent neoadjuvant chemotherapy before radiotherapy. In addition to manual GTV contouring, automated segmentation algorithms were applied–among these 38%, 42%, 47% and 50% SUVmax as well as the PERCIST total lesion glycolysis (TLG) algorithm. Different ratios were calculated to assess the overlap of GTV and BTV including the conformity index and the ratio GTV included within the BTV. Median age of the patients was 66 years and median tumour SUVmax 9.2. Median size of the GTVs defined by the radiation oncologist was 43.7 ml. Median conformity indices were between 30.0–37.8%. The highest amount of BTV within GTV was seen with the 38% SUVmax algorithm (49.0%), the lowest with 50% SUVmax (36.0%). Best agreement was obtained for oesophageal cancer patients with a conformity index of 56.4% and BTV within GTV ratio of 71.1%. At present there is only low concordance between manually derived GTVs and automatically segmented FDG-PET/CT based BTVs indicating the need for further research in order to achieve higher volumetric conformity and therefore to get access to the full potential of FDG-PET/CT for optimization of radiotherapy planning

  8. Hypo-fractionated treatment in radiotherapy: radio-biological models Tcp and NTCP

    International Nuclear Information System (INIS)

    At the present time the breast cancer in Mexico has the first place of incidence of the malignant neoplasia s in the women, and represents 11.34% of all the cancer cases. On the other hand, the treatments for cancer by means of ionizing radiations have been dominated under the approaches of the medical radio-oncologists which have been based on test and error by many years. The radio-biological models, as the Tcp, NTCP and dosimetric variables, for their clinical application in the conventional radiotherapy with hypo-fractionation have as purpose predicting personalized treatment plans that they present most probability of tumor control and minor probability of late reactions, becoming this way support tools in the decisions taking for the patient treatments planning of Medical Physicists and Radio-oncologists. (Author)

  9. Biological dose representation for carbon-ion radiotherapy of unconventional fractionation

    CERN Document Server

    Kanematsu, Nobuyuki

    2016-01-01

    In carbon-ion radiotherapy, single-beam delivery each day in alternate directions has been commonly practiced for operational efficiency, taking advantage of the Bragg peak and the relative biological effectiveness (RBE) for uniform dose conformation to a tumor. The treatment plans are usually evaluated with total RBE-weighted dose, which is however deficient in relevance to the biological effect in the linear-quadratic model due to its quadratic-dose term, or the dose-fractionation effect. In this study, we reformulate the extrapolated response dose (ERD), or synonymously BED, which normalizes the dose-fractionation and cell-repopulation effects as well as the RBE of treating radiation, based on inactivation of a single model cell system and a typical treating radiation in carbon-ion RT. The ERD distribution virtually represents the biological effect of the treatment regardless of radiation modality or fractionation scheme. We applied the ERD formulation to simplistic model treatments and to a preclinical su...

  10. Effect of contrast agent administration on consequences of dosimetry and biology in radiotherapy planning

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Ching-Jung [Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, 259 Wen-Hua 1st Road, Kwei-Shan, Tao-Yuan 333 Taiwan (China); Department of Radiation Oncology, Chang Gung Memorial Hospital, Kwei-Shan, Tao-Yuan 333 Taiwan (China); Yang, Pei-Ying [Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, 259 Wen-Hua 1st Road, Kwei-Shan, Tao-Yuan 333 Taiwan (China); Chao, Tsi-Chian, E-mail: chaot@mail.cgu.edu.tw [Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, 259 Wen-Hua 1st Road, Kwei-Shan, Tao-Yuan 333 Taiwan (China); Tu, Shu-Ju, E-mail: sjtu@mail.cgu.edu.tw [Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, 259 Wen-Hua 1st Road, Kwei-Shan, Tao-Yuan 333 Taiwan (China)

    2015-06-01

    In the treatment planning of radiation therapy, patients may be administrated with contrast media in CT scanning to assist physicians for accurate delineation of the target or organs. However, contrast media are not used in patients during the treatment delivery. In particular, contrast media contain materials with high atomic numbers and dosimetric variations may occur between scenarios where contrast media are present in treatment planning and absent in treatment delivery. In this study we evaluate the effect of contrast media on the dosimetry and biological consequence. An analytical phantom based on AAPM TG 119 and five sets of CT images from clinical patients are included. Different techniques of treatment planning are considered, including 1-field AP, 2-field AP+PA, 4-field box, 7-field IMRT, and RapidArc. RapidArc is a recent technique of volumetric modulated arc therapy and is used in our study of contrast media in clinical scenarios. The effect of RapidArc on dosimetry and biological consequence for administration of contrast media in radiotherapy is not discussed previously in literature. It is shown that dose difference is reduced as the number of external beams is increased, suggesting RapidArc may be favored to be used in the treatment planning enhanced by contrast media. Linear trend lines are fitted for assessment of percent dose differences in the planning target volume versus concentrations of contrast media between plans where contrast media are present and absent, respectively.

  11. Delayed biological effects of radiotherapy in 500 patients treated for cervical cancer

    International Nuclear Information System (INIS)

    The incidence of cancer of the uterine cervix is high in Ecuador, accounting for 45% of all cancer cases and 60% of cancer cases in women. This study considers the delayed biological effects of radiotherapy in 500 patients out of 3200 treated between 1957 and 1972. In spite of the large number of patients treated, it was possible to follow up only 500 cases because a large proportion were in stage IV of the disease and many did not return for clinical check-up. Therefore a report is made on a study of 500 cases, considering a survival of at least five years. The study shows what were the delayed biological effects of radiation treatment and also the frequency and chronology of the appearance of lesions. The following sequelae are studied: severe sclerosis of the skin and subcutaneous cell tissue, whether or not followed by necrosis; chronic oedema of the lower extremities which is conducive to the recurring phenomena of infection in those organs; damage to the pelvic girdle; coxo-femoral osteoarthrosis and necrosis of the femur head; fracture of the neck of the femur and the pubis; serious lesions in the bladder and in the rectosigmoid; radiation cancer. The patients in question were treated regularly and always by the same technique; it is therefore possible to know the relation between these lesions and the following factors: tumour dose administered; radiation quality; mode of treatment (radiation therapy, alone or associated, before or after surgery); age of the patients treated. (author)

  12. Effect of contrast agent administration on consequences of dosimetry and biology in radiotherapy planning

    International Nuclear Information System (INIS)

    In the treatment planning of radiation therapy, patients may be administrated with contrast media in CT scanning to assist physicians for accurate delineation of the target or organs. However, contrast media are not used in patients during the treatment delivery. In particular, contrast media contain materials with high atomic numbers and dosimetric variations may occur between scenarios where contrast media are present in treatment planning and absent in treatment delivery. In this study we evaluate the effect of contrast media on the dosimetry and biological consequence. An analytical phantom based on AAPM TG 119 and five sets of CT images from clinical patients are included. Different techniques of treatment planning are considered, including 1-field AP, 2-field AP+PA, 4-field box, 7-field IMRT, and RapidArc. RapidArc is a recent technique of volumetric modulated arc therapy and is used in our study of contrast media in clinical scenarios. The effect of RapidArc on dosimetry and biological consequence for administration of contrast media in radiotherapy is not discussed previously in literature. It is shown that dose difference is reduced as the number of external beams is increased, suggesting RapidArc may be favored to be used in the treatment planning enhanced by contrast media. Linear trend lines are fitted for assessment of percent dose differences in the planning target volume versus concentrations of contrast media between plans where contrast media are present and absent, respectively

  13. Biologically effective doses of postoperative radiotherapy in the prevention of keloids. Dose-effect relationship

    International Nuclear Information System (INIS)

    Purpose: To review the recurrence rates of keloids after surgical excision followed by radiotherapy, and to answer the question whether after normalization of the dose, a dose-effect relationship could be derived. Material and Methods: A literature search was performed to identify studies dealing with the efficacy of various irradiation regimes for the prevention of keloids after surgery. Biologically effective doses (BEDs) of the various irradiation regimens were calculated using the linear-quadratic concept. A distinction between recurrence rates of keloids in the face and neck region and those in other parts of the body was made. Results: 31 reports were identified with PubMed with the search terms keloids, surgery, radiation therapy, radiotherapy. 13 reports were excluded, because no link could be found between recurrence rate and dose, or if less than ten patients per dose group. The recurrence rate for surgery only was 50-80%. For BED values >10 Gy the recurrence rate decreased as a function of BED. For BED values >30 Gy the recurrence rate was <10%. For a given dose, the recurrence rates of keloids in the sites with high stretch tension were not significantly higher than in sites without stretch tension. Conclusion: The results of this study indicate that for effectively treating keloids postoperatively, a relatively high dose must be applied in a short overall treatment time. The optimal treatment probably is an irradiation scheme resulting in a BED value of at least 30 Gy. A BED value of 30 Gy can be obtained with, for instance, a single acute dose of 13 Gy, two fractions of 8 Gy two fractions of 8 Gy or three fractions of 6 Gy, or a single dose of 27 Gy at low dose rate. The radiation treatment should be administered within 2 days after surgery. (orig.)

  14. Use of artificial neural networks to predict biological outcomes for patients receiving radical radiotherapy of the prostate

    International Nuclear Information System (INIS)

    Background and purpose: This paper discusses the application of artificial neural networks (ANN) in predicting biological outcomes following prostate radiotherapy. A number of model-based methods have been developed to correlate the dose distributions calculated for a patient receiving radiotherapy and the radiobiological effect this will produce. Most widely used are the normal tissue complication probability and tumour control probability models. An alternative method for predicting specific examples of tumour control and normal tissue complications is to use an ANN. One of the advantages of this method is that there is no need for a priori information regarding the relationship between the data being correlated. Patients and methods: A set of retrospective clinical data from patients who received radical prostate radiotherapy was used to train ANNs to predict specific biological outcomes by learning the relationship between the treatment plan prescription, dose distribution and the corresponding biological effect. The dose and volume were included as a differential dose-volume histogram in order to provide a holistic description of the available data. Results: It was shown that the ANNs were able to predict biochemical control and specific bladder and rectum complications with sensitivity and specificity of above 55% when the outcomes were dichotomised. It was also possible to analyse information from the ANNs to investigate the effect of individual treatment parameters on the outcome. Conclusion: ANNs have been shown to learn something of the complex relationship between treatment parameters and outcome which, if developed further, may prove to be a useful tool in predicting biological outcomes

  15. A biological aspect on radium therapy, and approach to new radiotherapy by several sessions a day

    International Nuclear Information System (INIS)

    Through radiobiological study of treatment with radium, it was revealed that radium therapy has two such important features as (1) short overall treatment time and (2) low-dose rate irradiation and that it showed a higher therapeutic ratio than that of conventional high-dose rate fractionated irradiation. After searching for a high-dose rate irradiation method with these advantages of radium treatment, results were obtained which suggested the possibility of new radio-therapy with several sessions a day. In the new method, a small dose was applied several times a day. Then, the time-dose relationship of the new therapy was investigated, and an attempt was made to calculate the dose fractionation that seemed practical. The results obtained were in good agreement with those of Svoboda's recent clinical experience. However, since these results were based on many biological hypotheses, clinical application of them at present is risky. Prior to clinical application, it will be necessary to conduced a number of animal experiments. (auth.)

  16. Modelling beam transport and biological effectiveness to develop treatment planning for ion beam radiotherapy

    CERN Document Server

    Grzanka, Leszek

    2014-01-01

    Radiation therapy with carbon ions is a novel technique of cancer radiotherapy, applicable in particular to treating radioresistant tumours at difficult localisations. Therapy planning, where the medical physicist, following the medical prescription, finds the optimum distribution of cancer cells to be inactivated by their irradiation over the tumour volume, is a basic procedure of cancer radiotherapy. The main difficulty encountered in therapy planning for ion radiotherapy is to correctly account for the enhanced radiobiological effectiveness of ions in the Spread Out Bragg Peak (SOBP) region over the tumour volume. In this case, unlike in conventional radiotherapy with photon beams, achieving a uniform dose distribution over the tumour volume does not imply achieving uniform cancer cell inactivation. In this thesis, an algorithm of the basic element (kernel) of a treatment planning system (TPS) for carbon ion therapy is developed. The algorithm consists of a radiobiological part which suitably corrects for ...

  17. Evaluation of conformal radiotherapy techniques through physics and biologic criteria; Avaliacao de tecnicas radioterapicas conformacionais utilizando criterios fisicos e biologicos

    Energy Technology Data Exchange (ETDEWEB)

    Bloch, Jonatas Carrero

    2012-07-01

    In the fight against cancer, different irradiation techniques have been developed based on technological advances and aiming to optimize the elimination of tumor cells with the lowest damage to healthy tissues. The radiotherapy planning goal is to establish irradiation technical parameters in order to achieve the prescribed dose distribution over the treatment volumes. While dose prescription is based on radiosensitivity of the irradiated tissues, the physical calculations on treatment planning take into account dosimetric parameters related to the radiation beam and the physical characteristics of the irradiated tissues. To incorporate tissue's radiosensitivity into radiotherapy planning calculations can help particularize treatments and establish criteria to compare and elect radiation techniques, contributing to the tumor control and the success of the treatment. Accordingly, biological models of cellular response to radiation have to be well established. This work aimed to study the applicability of using biological models in radiotherapy planning calculations to aid evaluating radiotherapy techniques. Tumor control probability (TCP) was studied for two formulations of the linear-quadratic model, with and without repopulation, as a function of planning parameters, as dose per fraction, and of radiobiological parameters, as the α/β ratio. Besides, the usage of biological criteria to compare radiotherapy techniques was tested using a prostate planning simulated with Monte Carlo code PENELOPE. Afterwards, prostate planning for five patients from the Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto, USP, using three different techniques were compared using the tumor control probability. In that order, dose matrices from the XiO treatment planning system were converted to TCP distributions and TCP-volume histograms. The studies performed allow the conclusions that radiobiological parameters can significantly influence tumor control

  18. Radiation biology: Major advances and perspectives for radiotherapy; Biologie des radiations: avancees majeures et perspectives pour la radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Joubert, A. [Societe Magelis, lotissement Bel-Air, 6, rue Frederic-Mistral, 84160 Cadenet (France); Vogin, G.; Granzotto, A. [CR-U1052, centre de recherche en cancerologie de Lyon, Inserm, batiment Cheney A, 28, rue Laennec, 69008 Lyon (France); Centre d' hadrontherapie etoile, 60, avenue Rockfeller, 69008 Lyon (France); Devic, C.; Viau, M.; Thomas, C.; Foray, N. [CR-U1052, centre de recherche en cancerologie de Lyon, Inserm, batiment Cheney A, 28, rue Laennec, 69008 Lyon (France); Maalouf, M. [CR-U1052, centre de recherche en cancerologie de Lyon, Inserm, batiment Cheney A, 28, rue Laennec, 69008 Lyon (France); Centre national d' etudes spatiales, 2, place Maurice-Quentin, 75039 Paris cedex 01 (France); Colin, C. [EA3738, faculte de medecine Lyon-Sud, 69921 Oullins (France); Service de radiologie, centre hospitalo-universitaire Lyon-Sud, chemin du Grand-Revoyet, 69495 Pierre-Benite (France)

    2011-08-15

    At the beginning of the 21. century, radiation biology is at a major turning point in its history. It must meet the expectations of the radiation oncologists, radiologists and the general public, but its purpose remains the same: to understand the molecular, cellular and tissue levels of lethal and carcinogenic effects of ionizing radiation in order to better protect healthy tissues and to develop treatments more effective against tumours. Four major aspects of radiobiology that marked this decade will be discussed: technological developments, the importance of signalling and repair of radiation-induced deoxyribonucleic acid (DNA) damage, the impact of individual factor in the response to radiation and the contribution of radiobiology to better choose innovative therapies such as proton-therapy or stereotactic body radiation therapy (SBRT). A translational radiobiology should emerge with the help of radiotherapists and radiation physicists and by facilitating access to the new radio and/or chemotherapy modalities. (authors)

  19. Validation of 3'-deoxy-3'-fluorine-18-fluorothymidine positron emission tomography for image-guidance in biologically adaptive radiotherapy

    Science.gov (United States)

    Axente, Marian

    Accelerated tumor cell repopulation during radiation therapy is one of the leading causes for low survival rates of head-and-neck cancer patients. The therapeutic effectiveness of radiotherapy could be improved by selectively targeting proliferating tumor subvolumes with higher doses of radiation. Positron emission tomography (PET) imaging with 3'-deoxy-3 '-18F-fluorothymidine (FLT) has shown great potential as a non-invasive approach to characterizing the proliferation status of tumors. This thesis focuses on histopathological validation of FLT PET imaging specifically for image-guidance applications in biologically adaptive radiotherapy. The lack of experimental data supporting the use of FLT PET imaging for radiotherapy guidance is addressed by developing a novel methodology for histopathological validation of PET imaging. Using this new approach, the spatial concordance between the intratumoral pattern of FLT uptake and the spatial distribution of cell proliferation is demonstrated in animal tumors. First, a two-dimensional analysis is conducted comparing the microscopic FLT uptake as imaged with autoradiography and the distribution of active cell proliferation markers imaged with immunofluorescent microscopy. It was observed that when tumors present a pattern of cell proliferation that is highly dispersed throughout the tumor, even high-resolution imaging modalities such as autoradiography could not accurately determine the extent and spatial distribution of proliferative tumor subvolumes. While microscopic spatial coincidence between high FLT uptake regions and actively proliferative subvolumes was demonstrated in tumors with highly compartmentalized/aggregated features of cell proliferation, there were no conclusive results across the entire set of utilized tumor specimens. This emphasized the need for addressing the limited resolution of FLT PET when imaging microscopic patterns of cell proliferation. This issue was emphasized in the second part of the

  20. DIFFERENCE IN BIOLOGICAL CHARACTERISTICS AND SENSITIVITY TO CHEMOTHERAPY AND RADIOTHERAPY BETWEEN INTRAHEPATIC AND EXTRAHEPATIC CHOLANGIOCARCINOMA CELLS IN VITRO

    Institute of Scientific and Technical Information of China (English)

    Xiao-ran He; Xiao-peng Wu

    2008-01-01

    Objective To investigate and compare the biological characteristics and sensitivity to chemotherapy and radiother-apy of intrahepatic and extrahepatie cholangiocarcinoma cells in vitro.Methods The intrahepatic and extrahepatie eholangiocarcinoma cell lines were established, and cells with steady passage were chosen to study the biological characteristics including morphology, growth dynamics, chromosome, and levels of cancer antigen (CA)125, CA 19-9, alpha-fetoprotein (AFP), and carcino-embryonic antigen (CEA).M.eanwhile, MTT assay was used to determine the sensitivity of both kinds of cells to 6 chemotherapeutic drugs, inclu-ding cisplatin, paclitaxel, harringtonine, 5-fluorouracil, vincristine, and aelacimomycin, and the inhibitory rate of ceils under the irradiation of 10 Gy ray was also measured.Reanlts The intrahepatic cholangiocarcinoma cells were mostly fusiform in shape, and extrahepatic eholangiocar-cinoma cells were mostly round or polygon in shape. Their doubling time was 26. 3 hours and 23.1 hours, respectively.Their average number of chromosomes was 59 (range, 38-84) and 67 (range, 49-103 ), respectively. The chromo-some karyotypes of most intrahepatlc ebolangiocarcinoma cells were hyperdiploid and hypotriploid, while hypertriploid was predominant in extrahepatic cholangioearcinoma cells. The level of CA 125 in supernatant of extrahepatic cholangio-carcinoma cells increased obviously, while levels of other determined tumor markers in both kinds of cells were all with-in normal range. The intrahepatic cholangiocarcinoma cells were low sensitive to cisplatin and paclitaxel, but not sensi-tive to the other 4 chemotherapeutic drugs. The extrahepatic cholangiocarcinoma cells were high sensitive to eisplatin,but not sensitive to the other 5 drugs. Both kinds of cells had poor sensitivity to radiotherapy.Conelusions Intrahepatic and extrahepatie cbolangiocareinoma cells show differences in shape, doubling time,chromosome karyotype, tumor marker level, and

  1. Response of Chinese hamster ovary cells to fast neutron radiotherapy beams. I. Relative biological effectiveness and oxygen enhancement ratio

    International Nuclear Information System (INIS)

    The relative biological effectiveness (RBE) and oxygen enhancement ratio (OER) were determined for fast neutron beams produced by both 16-MeV and 50-MeV 2H on Be at the Texas A and M Variable Energy Cyclotron (TAMVEC). These beams have average neutron energies of 7 and 21 MeV, respectively. The biological system used in these experiments was Chinese hamster ovary cells in tissue culture. The results indicated that although the RBE of the 21-MeV beam was about 15 percent lower than that for the 7-MeV beam at 0.1 percent survival there was no change in RBE for either beam with depth in a tissue-equivalent phantom. The OER of the 7-MeV beam was found to be 1.5 +- 0.3 and the 21-MeV beam had an OER of 1.2 +- 0.2, which resulted in gain factors of 1.7 and 2.1, respectively, when compared to 60Co gamma rays (OER = 2.5). No variation in OER with depth was detected. It was concluded that the 21-MeV TAMVEC beam should be as applicable to radiotherapy from the radiobiological point of view as a 7-MeV beam

  2. Performance of the Gemini Planet Imager's adaptive optics system.

    Science.gov (United States)

    Poyneer, Lisa A; Palmer, David W; Macintosh, Bruce; Savransky, Dmitry; Sadakuni, Naru; Thomas, Sandrine; Véran, Jean-Pierre; Follette, Katherine B; Greenbaum, Alexandra Z; Ammons, S Mark; Bailey, Vanessa P; Bauman, Brian; Cardwell, Andrew; Dillon, Daren; Gavel, Donald; Hartung, Markus; Hibon, Pascale; Perrin, Marshall D; Rantakyrö, Fredrik T; Sivaramakrishnan, Anand; Wang, Jason J

    2016-01-10

    The Gemini Planet Imager's adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. A definitive description of the system's algorithms and technologies as built is given. 564 AO telemetry measurements from the Gemini Planet Imager Exoplanet Survey campaign are analyzed. The modal gain optimizer tracks changes in atmospheric conditions. Science observations show that image quality can be improved with the use of both the spatially filtered wavefront sensor and linear-quadratic-Gaussian control of vibration. The error budget indicates that for all targets and atmospheric conditions AO bandwidth error is the largest term. PMID:26835769

  3. Cells responsible for tumor surveillance in man: effects of radiotherapy, chemotherapy, and biologic response modifiers

    International Nuclear Information System (INIS)

    Currently, the most probable theory of tumor surveillance is neither the existence of any tumor-specific, antigen-dependent, T-cell-mediated cytotoxic effect that could eliminate spontaneous tumors in man and that could be used for some kind of vaccination against tumors, nor the complete absence of any surveillance or defense systems against tumors. What is probable is the cooperation of a number of antigen-independent, relatively weakly cytotoxic or possibly only cytostatic humoral and cellular effects, including nutritional immunity, tumor necrosis factor, certain cytokines, and the cytotoxic effects mediated by macrophages, NK cells, NK-like cells, and certain stimulated T-cells. One question remaining to be solved is why these antigen-independent effects do not attack normal cells. A number of plausible hypotheses are discussed. The hypothetical surveillance system is modulated both by traditional cancer treatment and by attempts at immunomodulation. Radiotherapy reduced the T-helper cell function for almost a decade, but not those of macrophages or NK cells. T-cell changes have no prognostic implication, supporting, perhaps, the suggestion of a major role for macrophages and NK cells. Cyclic adjuvant chemotherapy reduces the peripheral lymphocyte population and several lymphocyte functions but not NK activity. Most of the parameters were normalized some years following treatment, but NK activity remained elevated and Th/Ts cell ratio was still decreased. This might possibly be taken to support the surveillance role of NK cells. Bestatin increases the frequency of lymphocytes forming rosettes with sheep red blood cells (but not their mitogenic responses), enhances NK activity, and augments the phagocytic capacity of granulocytes and monocytes (but not their cytotoxic activity). 154 references

  4. IsoBED: a tool for automatic calculation of biologically equivalent fractionation schedules in radiotherapy using IMRT with a simultaneous integrated boost (SIB) technique

    OpenAIRE

    Benassi Marcello; Pedrini Massimo; Abate Armando; Bruzzaniti Vicente; Strigari Lidia

    2011-01-01

    Abstract Background An advantage of the Intensity Modulated Radiotherapy (IMRT) technique is the feasibility to deliver different therapeutic dose levels to PTVs in a single treatment session using the Simultaneous Integrated Boost (SIB) technique. The paper aims to describe an automated tool to calculate the dose to be delivered with the SIB-IMRT technique in different anatomical regions that have the same Biological Equivalent Dose (BED), i.e. IsoBED, compared to the standard fractionation....

  5. Study of the biological and clinical effects caused by neutron on charged-particle radiotherapy

    International Nuclear Information System (INIS)

    During the particle therapy, a lot of secondly particles are generated through nuclear reactions in a patient's body or irradiation devices. Because the neutron is distributed broadly and its relative biological effectiveness (RBE) is high, an evaluation of second cancer risk should be associated with neutrons. Therefore we studied the distribution of secondly neutrons in a human phantom by metal foil activation method and compared with the estimation of Monte Carlo code PHITS (Particle and Heavy Ion Transport code System). The experiment was performed at BIO beam port of the Heavy Ion Medical Accelerator in Chiba (HIMAC) in National Institute of Radiological Sciences (NIRS) with 400 MeV/u carbon beam. Al, Co, Fe and Bi foils were used in this study. The metal foils were placed in a human phantom. The yield of isotopes produced in the foil by the incidence of neutrons was measured by counting corresponding emitted gamma ray with a Ge detector. Activation rate was estimated with the experimental result and calculation by PHITS. Neutron distribution inside of the human phantom was measured by metal foil activation method and the result was compared with PHITS. Through the comparison it is found that estimation of neutron spectrum by PHITS reproduces experimental result around a several dozen MeV. (author)

  6. Endosialin expression in relation to clinicopathological and biological variables in rectal cancers with a Swedish clinical trial of preoperative radiotherapy

    International Nuclear Information System (INIS)

    The importance of changes in tumour-associated stroma for tumour initiation and progression has been established. Endosialin is expressed in fibroblasts and pericytes of blood vessels in several types of tumours, and is involved in the progression of colorectal cancer. In order to see whether endosialin was related to radiotherapy (RT) response, and clinicopathological and biological variables, we investigated endosialin expression in rectal cancers from the patients who participated in a Swedish clinical trial of preoperative RT. Endosialin was immunohistochemically examined in normal mucosa, including distant (n = 72) and adjacent (n = 112) normal mucosa, and primary tumours (n = 135). Seventy-three of 135 patients received surgery alone and 62 received additional preoperative RT. Endosialin expression in the stroma increased from normal mucosa to tumour (p < 0.0001) both in RT and non-RT group. In the RT group, endosialin expression in the stroma was positively associated with expression of cyclooxygenase-2 (Cox-2) (p = 0.03), p73 (p = 0.01) and phosphates of regenerating liver (PRL) (p = 0.002). Endosialin expression in the tumour cells of both in the RT group (p = 0.01) and the non-RT group (p = 0.06) was observed more often in tumours with an infiltrative growth pattern than in tumours with an expansive growth pattern. In the RT group, endosialin expression in tumour cells was positively related to PRL expression (p = 0.02), whereas in the non-RT group, endosialin expression in tumour cells was positively related to p73 expression (p = 0.01). Endosialin expression may be involved in the progression of rectal cancers, and was related to Cox-2, p73 and PRL expression. However, a direct relationship between endosialin expression and RT responses in patients was not found

  7. Vascular Complications After Radiotherapy in Head and Neck Free Flap Reconstruction: Clinical Outcome Related to Vascular Biology.

    Science.gov (United States)

    Tall, Jael; Björklund, Tinna Christersdottir; Skogh, Ann-Charlott Docherty; Arnander, Claes; Halle, Martin

    2015-09-01

    Radiotherapy as a risk factor for free flap failure has been widely debated. The purpose of this study was to investigate vascular complications in free flap surgery at a center advocating preoperative radiotherapy. On the basis of previous experimental studies, we also aimed to investigate temporal aspects of vascular complications in both arteries and veins. Furthermore, we aimed to study the effect of tissue plasminogen activator (tPA), because irradiated microvascular recipient vessels are associated with impaired fibrinolysis.A retrospective review was conducted for 344 consecutive head and neck microvascular reconstructions. Radiotherapy was administered previously in 283 (82%) of the cases, median dose 64 Gy. Flap outcome, vascular complications, and salvage attempts were identified, along with time elapsed from completed radiotherapy, described as early (15 weeks) reconstructions.Total flap loss was more common in irradiated cases (P = 0.035), among which flap failure increased with time elapsed from the last radiotherapy session to surgery (P = 0.021). Among 30 registered vascular complications, venous thrombosis was the most common type and increased in delayed, compared to early, reconstructions (P = 0.012). Increased salvage rates were observed when tPA was administered intraoperatively (P = 0.015).The present study indicates that previous radiotherapy is a risk factor for head and neck free flap failure, especially in delayed reconstructions. This may be linked to previous findings of impaired fibrinolysis in irradiated microvascular recipient veins, which is further supported by the beneficial effect of tPA during salvage surgery. We emphasize the importance of early reconstruction after radiotherapy and suggest that there is a role for fibrinolytic agents during free flap salvage surgery in previously irradiated subjects. PMID:25003403

  8. Raster image adaptation for mobile devices using profiles

    Science.gov (United States)

    Rosenbaum, René; Hamann, Bernd

    2012-02-01

    Focusing on digital imagery, this paper introduces a strategy to handle heterogeneous hardware in mobile environments. Constrained system resources of most mobile viewing devices require contents that are tailored to the requirements of the user and the capabilities of the device. Appropriate image adaptation is still an unsolved research question. Due to the complexity of the problem, available solutions are either too resource-intensive or inflexible to be more generally applicable. The proposed approach is based on scalable image compression and progressive refinement as well as data and user profiles. A scalable image is created once and used multiple times for different kinds of devices and user requirements. Profiles available on the server side allow for an image representation that is adapted to the most important resources in mobile computing: screen space, computing power, and the volume of the transmitted data. Options for progressively refining content thereby allow for a fluent viewing experience during adaptation. Due to its flexibility and low complexity, the proposed solution is much more general compared to related approaches. To document the advantages of our approach we provide empirical results obtained in experiments with an implementation of the method.

  9. Hypo-fractionated treatment in radiotherapy: radio-biological models Tcp and NTCP; Tratamiento hipofraccionado en radioterapia: modelos radiobiologicos TCP y NTCP

    Energy Technology Data Exchange (ETDEWEB)

    Astudillo V, A. J.; Mitsoura, E. [Universidad Autonoma del Estado de Mexico, Facultad de Medicina, Paseo Tollocan s/n, 50180 Toluca, Estado de Mexico (Mexico); Paredes G, L. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Resendiz G, G., E-mail: lydia.paredes@inin.gob.mx [Hospital Medica Sur, Departamento de Radioterapia, Puente de Piedra 150, Col. Toriello Guerra, 14050 Mexico D. F. (Mexico)

    2014-08-15

    At the present time the breast cancer in Mexico has the first place of incidence of the malignant neoplasia s in the women, and represents 11.34% of all the cancer cases. On the other hand, the treatments for cancer by means of ionizing radiations have been dominated under the approaches of the medical radio-oncologists which have been based on test and error by many years. The radio-biological models, as the Tcp, NTCP and dosimetric variables, for their clinical application in the conventional radiotherapy with hypo-fractionation have as purpose predicting personalized treatment plans that they present most probability of tumor control and minor probability of late reactions, becoming this way support tools in the decisions taking for the patient treatments planning of Medical Physicists and Radio-oncologists. (Author)

  10. Challenges in using 18 F-fluorodeoxyglucose-PET-CT to define a biological radiotherapy boost volume in locally advanced pancreatic cancer

    International Nuclear Information System (INIS)

    The best method of identifying regions within pancreatic tumours that might benefit from an increased radiotherapy dose is not known. We investigated the utility of pre-treatment FDG-PET in predicting the spatial distribution of residual metabolic activity following chemoradiotherapy (CRT) in locally advanced pancreatic cancer (LAPC). 17 patients had FDG-PET/CT scans at baseline and six weeks post-CRT. Tumour segmentation was performed at 40% and 50% of SUVmax at baseline and 60%, 70%, 80% and 90% post-CRT. FDG-PET scans were non-rigidly registered to the radiotherapy planning CT using the CT component of the FDG-PET/CT. Percentage overlap of the post-CRT volumes with the pre-CRT volumes with one another and the gross tumour volume (GTV) was calculated. SUVmax decreased during CRT (median pre- 8.0 and post- 3.6, p < 0.0001). For spatial correlation analysis, 9 pairs of scans were included (Four were excluded following complete metabolic response, one patient had a non-FDG avid tumour, one had no post-CRT imaging, one had diffuse FDG uptake that could not be separated from normal tissues and one had an elevated blood glucose). The Pre40% and 50% of SUVmax volumes covered a mean of 50.8% and 30.3% of the GTV respectively. The mean% overlap of the 90%, 80%, 70%, 60% of SUVmax post-CRT with the Pre40% and Pre50% volumes were 83.3%, 84.0%, 83.7%, 77.9% and 77.8%, 69.9%, 74.5%, 64.8% respectively. Regions of residual metabolic activity following CRT can be predicted from the baseline FDG-PET and could aid definition of a biological target volume for non-uniform dose prescriptions

  11. IsoBED: a tool for automatic calculation of biologically equivalent fractionation schedules in radiotherapy using IMRT with a simultaneous integrated boost (SIB technique

    Directory of Open Access Journals (Sweden)

    Benassi Marcello

    2011-05-01

    Full Text Available Abstract Background An advantage of the Intensity Modulated Radiotherapy (IMRT technique is the feasibility to deliver different therapeutic dose levels to PTVs in a single treatment session using the Simultaneous Integrated Boost (SIB technique. The paper aims to describe an automated tool to calculate the dose to be delivered with the SIB-IMRT technique in different anatomical regions that have the same Biological Equivalent Dose (BED, i.e. IsoBED, compared to the standard fractionation. Methods Based on the Linear Quadratic Model (LQM, we developed software that allows treatment schedules, biologically equivalent to standard fractionations, to be calculated. The main radiobiological parameters from literature are included in a database inside the software, which can be updated according to the clinical experience of each Institute. In particular, the BED to each target volume will be computed based on the alpha/beta ratio, total dose and the dose per fraction (generally 2 Gy for a standard fractionation. Then, after selecting the reference target, i.e. the PTV that controls the fractionation, a new total dose and dose per fraction providing the same isoBED will be calculated for each target volume. Results The IsoBED Software developed allows: 1 the calculation of new IsoBED treatment schedules derived from standard prescriptions and based on LQM, 2 the conversion of the dose-volume histograms (DVHs for each Target and OAR to a nominal standard dose at 2Gy per fraction in order to be shown together with the DV-constraints from literature, based on the LQM and radiobiological parameters, and 3 the calculation of Tumor Control Probability (TCP and Normal Tissue Complication Probability (NTCP curve versus the prescribed dose to the reference target.

  12. A novel smartphone ophthalmic imaging adapter: User feasibility studies in Hyderabad, India

    OpenAIRE

    Ludwig, Cassie A.; Murthy, Somasheila I.; Pappuru, Rajeev R.; Alexandre Jais; Myung, David J; Chang, Robert T

    2016-01-01

    Aim of Study: To evaluate the ability of ancillary health staff to use a novel smartphone imaging adapter system (EyeGo, now known as Paxos Scope) to capture images of sufficient quality to exclude emergent eye findings. Secondary aims were to assess user and patient experiences during image acquisition, interuser reproducibility, and subjective image quality. Materials and Methods: The system captures images using a macro lens and an indirect ophthalmoscopy lens coupled with an iPhone 5S. We...

  13. Radiotherapy; Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-01

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

  14. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  15. Differential risk assessments from five hypoxia specific assays: The basis for biologically adapted individualized radiotherapy in advanced head and neck cancer patients

    DEFF Research Database (Denmark)

    Nordsmark, Marianne; Eriksen, Jesper Grau; Gebski, Val; Alsner, Jan; Horsman, Michael Robert; Overgaard, Jens

    2007-01-01

    PURPOSE: Hypoxia adversely relates with prognosis in human tumours. Five hypoxia specific predictive marker assays were compared and correlated with definitive radiotherapy. PATIENTS AND METHODS: Sixty-seven patients with advanced head and neck carcinomas were studied for pre-treatment plasma...... osteopontin measured by ELISA, tumour oxygenation status using pO(2) needle electrodes and tumour osteopontin, hypoxia inducible factor 1alpha (HIF-1alpha) and carboxyanhydrase 9 (CA9) by immunohistochemistry. The primary treatment was radiotherapy and the hypoxic radiosensitizer nimorazole. Loco......-regional tumour control was evaluated at 5 years. RESULTS: All five markers showed inter-tumour variability. Inter-marker correlations were inconsistent. Only plasma osteopontin inversely correlated with median tumour pO(2), (p=0.02, r=0.28) and CA9 correlated with HIF-1alpha (p<0.01, r=0.45). In Kaplan...

  16. Proceedings of 19. symposium on experimental radiotherapy and clinical radiobiology

    International Nuclear Information System (INIS)

    The proceedings include review contributions on radio-oncology, and new radiation technologies and molecular prediction; and poster sessions on the following topics: hypoxia; molecular mechanisms of radiation resistance; molecular targeting; DNA repair; biological imaging; biology of experimental radiations; normal tissue toxicity; modern radiotherapy; tumor hypoxia and metabolic micro milieu; immune system and radiotherapy.

  17. Palliative Radiotherapy

    International Nuclear Information System (INIS)

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

  18. Higher Biologically Effective Dose of Radiotherapy Is Associated With Improved Outcomes for Locally Advanced Non–Small Cell Lung Carcinoma Treated With Chemoradiation: An Analysis of the Radiation Therapy Oncology Group

    International Nuclear Information System (INIS)

    Purpose: Patients treated with chemoradiotherapy for locally advanced non–small-cell lung carcinoma (LA-NSCLC) were analyzed for local-regional failure (LRF) and overall survival (OS) with respect to radiotherapy dose intensity. Methods and Materials: This study combined data from seven Radiation Therapy Oncology Group (RTOG) trials in which chemoradiotherapy was used for LA-NSCLC: RTOG 88-08 (chemoradiation arm only), 90-15, 91-06, 92-04, 93-09 (nonoperative arm only), 94-10, and 98-01. The radiotherapeutic biologically effective dose (BED) received by each individual patient was calculated, as was the overall treatment time-adjusted BED (tBED) using standard formulae. Heterogeneity testing was done with chi-squared statistics, and weighted pooled hazard ratio estimates were used. Cox and Fine and Gray’s proportional hazard models were used for OS and LRF, respectively, to test the associations between BED and tBED adjusted for other covariates. Results: A total of 1,356 patients were analyzed for BED (1,348 for tBED). The 2-year and 5-year OS rates were 38% and 15%, respectively. The 2-year and 5-year LRF rates were 46% and 52%, respectively. The BED (and tBED) were highly significantly associated with both OS and LRF, with or without adjustment for other covariates on multivariate analysis (p < 0.0001). A 1-Gy BED increase in radiotherapy dose intensity was statistically significantly associated with approximately 4% relative improvement in survival; this is another way of expressing the finding that the pool-adjusted hazard ratio for survival as a function of BED was 0.96. Similarly, a 1-Gy tBED increase in radiotherapy dose intensity was statistically significantly associated with approximately 3% relative improvement in local-regional control; this is another way of expressing the finding that the pool-adjusted hazard ratio as a function of tBED was 0.97. Conclusions: Higher radiotherapy dose intensity is associated with improved local-regional control

  19. Dosimetry in radiotherapy. V.1

    International Nuclear Information System (INIS)

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  20. Dosimetry in radiotherapy. V.2

    International Nuclear Information System (INIS)

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  1. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-10-01

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

  2. Small animal radiotherapy research platforms

    International Nuclear Information System (INIS)

    Advances in conformal radiation therapy and advancements in pre-clinical radiotherapy research have recently stimulated the development of precise micro-irradiators for small animals such as mice and rats. These devices are often kilovolt x-ray radiation sources combined with high-resolution CT imaging equipment for image guidance, as the latter allows precise and accurate beam positioning. This is similar to modern human radiotherapy practice. These devices are considered a major step forward compared to the current standard of animal experimentation in cancer radiobiology research. The availability of this novel equipment enables a wide variety of pre-clinical experiments on the synergy of radiation with other therapies, complex radiation schemes, sub-target boost studies, hypofractionated radiotherapy, contrast-enhanced radiotherapy and studies of relative biological effectiveness, to name just a few examples. In this review we discuss the required irradiation and imaging capabilities of small animal radiation research platforms. We describe the need for improved small animal radiotherapy research and highlight pioneering efforts, some of which led recently to commercially available prototypes. From this, it will be clear that much further development is still needed, on both the irradiation side and imaging side. We discuss at length the need for improved treatment planning tools for small animal platforms, and the current lack of a standard therein. Finally, we mention some recent experimental work using the early animal radiation research platforms, and the potential they offer for advancing radiobiology research. (topical review)

  3. Small animal radiotherapy research platforms

    Science.gov (United States)

    Verhaegen, Frank; Granton, Patrick; Tryggestad, Erik

    2011-06-01

    Advances in conformal radiation therapy and advancements in pre-clinical radiotherapy research have recently stimulated the development of precise micro-irradiators for small animals such as mice and rats. These devices are often kilovolt x-ray radiation sources combined with high-resolution CT imaging equipment for image guidance, as the latter allows precise and accurate beam positioning. This is similar to modern human radiotherapy practice. These devices are considered a major step forward compared to the current standard of animal experimentation in cancer radiobiology research. The availability of this novel equipment enables a wide variety of pre-clinical experiments on the synergy of radiation with other therapies, complex radiation schemes, sub-target boost studies, hypofractionated radiotherapy, contrast-enhanced radiotherapy and studies of relative biological effectiveness, to name just a few examples. In this review we discuss the required irradiation and imaging capabilities of small animal radiation research platforms. We describe the need for improved small animal radiotherapy research and highlight pioneering efforts, some of which led recently to commercially available prototypes. From this, it will be clear that much further development is still needed, on both the irradiation side and imaging side. We discuss at length the need for improved treatment planning tools for small animal platforms, and the current lack of a standard therein. Finally, we mention some recent experimental work using the early animal radiation research platforms, and the potential they offer for advancing radiobiology research.

  4. Intraoperative radiotherapy

    International Nuclear Information System (INIS)

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

  5. Specific aspects of radiotherapy of malignant tumors in childhood

    International Nuclear Information System (INIS)

    Based on the experience with radiotherapy of malignant tumors in 1839 children treated at the Oncological Clinic in Prague from 1946 to 1985, the conclusion is arrived at that some specific aspects of radiotherapy of tumors in children, such as kinetics and biological features are so important that it can be considered a special sub-discipline of clinical radiotherapy. An opinion is expressed about the application of irradiation in non-malignant affections in children. (author). 2 figs., 4 tabs., 25 refs

  6. Imaging in radiotherapy

    International Nuclear Information System (INIS)

    The diagnostic methodologies used for the radiotherapy planning have undergone great developments in the last 30 years. Since the 1980s, after the introduction of the CT scanner, the modality for the planning moved beyond the planar 2D assessment to approach a real and more realistic volumetric 3D definition. Consequently the dose distribution, previously obtained by means of an overly simple approximation, became increasingly complex, better tailoring the true shape of the tumour. The final therapeutic improvement has been obtained by a parallel increase in the complexity of the irradiating units: the Linacs for therapy have, in fact, been equipped with a full accessory set capable to modulate the fluence (IMRT) and to check the correct target position continuously during the therapy session (IMRT-IGRT). The multimodal diagnostic approach, which integrates diagnostic information, from images of the patient taken with CT, NMR, PET and US, further improves the data for a biological and topological optimization of the radiotherapy plan and consequently of the dose distribution in the Planning Target Volume. Proteomic and genomic analysis will be the next step in tumour diagnosis. These methods will provide the planners with further information, for a true personalization of the treatment regimen and the assessment of the predictive essays for each tumour and each patient.

  7. Joint, Image-Adaptive Compression and Watermarking by GABased Wavelet Localization: Optimal Trade-Off between Transmission Time and Security

    Directory of Open Access Journals (Sweden)

    M. M. Ramya

    2012-12-01

    Full Text Available Teleradiology using internet can offer patients in remote locations the benefit of diagnosis and advice by a super specialist present in a metropolis. However, exchange of vital information such as the clinical images and textual facts in the public network poses challenges of transmission of large volume of data as well as prevention of the distortion of the images. In this paper, a novel application system to jointly compress and watermark the medical images in a near-lossless, image-adaptive adaptive fashion is proposed to address these challenges. The system design uses genetic algorithm for adaptive wavelet coding to generate compressed data and integration of dual watermarks to realize the security and authentication of the compressed data. The GA-based image adaptive compression provides feasible way to obtain optimal compression ratio without compromising the image fidelity upon subsequent watermarking. A multi-gene approach, with one gene coding for the embedding strength of the robust watermark and the other for the number of bits for embedding the semi-fragile watermark is used for optimal image-adaptive watermarking. A multi-parameter fitness function is designed to address the conflicting requirements of image compression, authenticity and integrity associated with teleradiology. Experimental results show the ability of the system to detect tampering and to limit the peak error between the original and the watermarked images. Moreover, as the watermarking is performed on the compressed image, the overhead for watermarking gets reduced.

  8. The potential of radiotherapy of lymphoma infiltrations of the CNS

    International Nuclear Information System (INIS)

    Radiotherapy is a very important element in the complex therapy of lymphomas of the central nervous system, significantly improving the results of the aggressive system chemotherapy. Irradiation of considerable tissue volumes and the application of rather high total doses are recommended. In view of the unfavorable prognosis and biological behavior of the tumor, the total treatment (including chemotherapy and radiotherapy) should be aggressive. (author)

  9. A novel smartphone ophthalmic imaging adapter: User feasibility studies in Hyderabad, India

    Directory of Open Access Journals (Sweden)

    Cassie A Ludwig

    2016-01-01

    Full Text Available Aim of Study: To evaluate the ability of ancillary health staff to use a novel smartphone imaging adapter system (EyeGo, now known as Paxos Scope to capture images of sufficient quality to exclude emergent eye findings. Secondary aims were to assess user and patient experiences during image acquisition, interuser reproducibility, and subjective image quality. Materials and Methods: The system captures images using a macro lens and an indirect ophthalmoscopy lens coupled with an iPhone 5S. We conducted a prospective cohort study of 229 consecutive patients presenting to L. V. Prasad Eye Institute, Hyderabad, India. Primary outcome measure was mean photographic quality (FOTO-ED study 1–5 scale, 5 best. 210 patients and eight users completed surveys assessing comfort and ease of use. For 46 patients, two users imaged the same patient's eyes sequentially. For 182 patients, photos taken with the EyeGo system were compared to images taken by existing clinic cameras: a BX 900 slit-lamp with a Canon EOS 40D Digital Camera and an FF 450 plus Fundus Camera with VISUPAC™ Digital Imaging System. Images were graded post hoc by a reviewer blinded to diagnosis. Results: Nine users acquired 719 useable images and 253 videos of 229 patients. Mean image quality was ≥ 4.0/5.0 (able to exclude subtle findings for all users. 8/8 users and 189/210 patients surveyed were comfortable with the EyeGo device on a 5-point Likert scale. For 21 patients imaged with the anterior adapter by two users, a weighted κ of 0.597 (95% confidence interval: 0.389–0.806 indicated moderate reproducibility. High level of agreement between EyeGo and existing clinic cameras (92.6% anterior, 84.4% posterior was found. Conclusion: The novel, ophthalmic imaging system is easily learned by ancillary eye care providers, well tolerated by patients, and captures high-quality images of eye findings.

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

    International Nuclear Information System (INIS)

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

  11. Optimisation in radiotherapy I. Defining the problem

    International Nuclear Information System (INIS)

    Optimisation in radiotherapy should incorporate a very wide set of variables, including the combinations of dose due to external beam radiotherapy, brachytherapy, internally administered radionuclides and the effects of chemotherapy, surgery, hyperthermia, other biological and chemical defenses, alternative treatment techniques, lifestyle and mental state of the patient, the economics of cancer treatment and consideration of tolerable levels of adverse effects and palliation. A full treatment optimisation would consider the influence and covariance of all these variables and any future techniques, as well as the complex constraints imposed by the biological systems being irradiated. This series of reviews concentrates on optimisation of radiotherapy through the treatment planning component of the treatment process - an area of radiotherapy research that has received a great deal of attention as the attached lists of references will testify. It hopes to provide the medical physics and engineering community (and hopefully the clinical community) with a background into the mathematical bases for the manipulation of radiation for clinical benefit. It also examines the potential benefits of research into these techniques in the light of recent approaches to optimisation in radiotherapy, and provides pointers to more concise accounts in the literature. In this first article, the incentive for radiotherapy optimisation research is established, and the actual radiotherapy optimisation problem (in terms of the manipulation of degrees of freedom in radiation delivery) is defined. The degrees of freedom associated with radiotherapy treatment are identified, and it is shown how these degrees of freedom translate into the mathematical parameters of the problem, including the dose distributions they produce. The constraints and objectives of the problem are also discussed from both physical and radiobiological perspectives. (author)

  12. Radiotherapy for Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-07-01

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

  13. Radiotherapy for Hodgkin lymphoma

    International Nuclear Information System (INIS)

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

  14. Anatomical imaging for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Philip M [Joint Physics Department, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT (United Kingdom)], E-mail: phil.evans@icr.ac.uk

    2008-06-21

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  15. Anatomical imaging for radiotherapy

    International Nuclear Information System (INIS)

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  16. Sorafenib and radiotherapy association for hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Conformal radiotherapy is a promising therapeutic strategy for hepatocellular carcinoma (HCC), producing local control rates above 90% within the radiation beam. However, survival after radiotherapy remains limited by the high frequency of intra- and extra-hepatic recurrences, which occurs in 40-50 and 20-30% of cases, respectively. Sorafenib (BAY43-9006, Nexavar; Bayer, West Haven, CT) is a small molecule inhibitor that demonstrated potent activity to target v-raf murine sarcoma oncogene homologue B1 (BRAF) and VEGFR tyrosine kinases. Sorafenib is the only drug that demonstrated effectiveness to increase overall survival in advanced or metastatic hepatocellular carcinoma. The rationale to combine radiotherapy with sorafenib is the following: (1) targeting RAS-RAF-MAPK and VEGFR signaling pathways, which are specifically activated after exposure to radiation, and responsible for radio-resistance phenomenon; (2) enhancing the oxygen effect through normalization of the surviving tumor vasculature; and (3) synchronization of the cell cycle. Sorafenib and radiotherapy represent complementary strategies, as radiotherapy may be useful to prolong the effect of sorafenib through control of the macroscopic disease, when sorafenib may target latent microscopic disease. Sorafenib and radiotherapy associations are thus based on a relevant biological and clinical rationale and are being evaluated in ongoing phase I-II trials. (authors)

  17. SU-E-T-55: Biological Equivalent Dose (BED) Comparison Between Permanent Interstitial Brachytherapy and Conventional External Beam Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Purpose: The goal of this research is to calculate and compare the Biological Equivalent Dose (BED) between permanent prostate Iodine-125 implant brachytherapy as monotherapy with the BED of conventional external beam radiation therapy (EBRT). Methods: A retrospective study of 605 patients treated with Iodine-125 seed implant was performed in which physician A treated 274 patients and physician B treated 331 patients. All the Brachytherapy treatment plans were created using VariSeed 8 planning system. The Iodine-125 seed source activities and loading patterns varied slightly between the two physicians. The prescription dose is 145 Gy to PTV for each patient. The BED and Tumor Control Probability (TCP) were calculated based on the TG 137 formulas. The BED for conventional EBRT of the prostate given in our institution in 2Gy per fraction for 38 fractions was calculated and compared. Results: Physician A treated 274 patients with an average BED of 123.92±0.87 Gy and an average TCP of 99.20%; Physician B treated 331 patients with an average BED of 124.87±1.12 Gy and an average TCP of 99.30%. There are no statistically significant differences (T-Test) between the BED and TCP values calculated for these two group patients.The BED of the patients undergoing conventional EBRT is calculated to be 126.92Gy. The BED of the patients treated with permanent implant brachytherapy and EBRT are comparable. Our BED and TCP values are higher than the reported values by TG 137 due to higher Iodine-125 seed activity used in our institution. Conclusion: We calculated the BED,a surrogate of the biological response to a permanent prostate brachytherapy using TG 137 formulas and recommendation. The TCP of better than 99% is calculated for these patients. A clinical outcome study of these patients correlating the BED and TCP values with PSA and Gleason Levels as well as patient survival is warranted

  18. Experimental radiotherapy and clinical radiobiology. Vol. 19. Proceedings; Experimentelle Strahlentherapie und Klinische Strahlenbiologie. Bd. 19. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Michael; Dahm-Daphi, Jochen; Dikomey, Ekkehard; Petersen, Cordula; Rodemann, H. Peter; Zips, Daniel (eds.)

    2010-12-18

    The proceedings include review contributions on radio-oncology, and new radiation technologies and molecular prediction; and poster sessions on the following topics: hypoxia; molecular mechanisms of radiation resistance; molecular targeting; DNA repair; biological imaging; biology of experimental radiations; normal tissue toxicity; modern radiotherapy; tumor hypoxia and metabolic micro milieu; immune system and radiotherapy.

  19. A biologically competitive 21 days hypofractionation scheme with weekly concomitant boost in breast cancer radiotherapy feasibility acute sub-acute and short term late effects

    International Nuclear Information System (INIS)

    Radiation therapy after lumpectomy is a standard part of breast conserving therapy for invasive breast carcinoma. The most frequently used schedule worldwide is 60 Gy in 30 fractions in 6 weeks, a time commitment that sporadically may dissuade some otherwise eligible women from undertaking treatment. The purpose and primary endpoint of this perspective study is to evaluate feasibility and short-term late toxicity in a hypofractionated whole breast irradiation schedule. Between February and October 2008 we treated 65 consecutive patients with operable invasive early-stage breast cancer with a hypofractionated schedule of external beam radiation therapy. All patients were assigned to 39 Gy in 13 fractions in 3 weeks to the whole breast plus a concomitant weekly boost dose to the lumpectomy cavity of 3 Gy in 3 fractions. All the patients had achieved a median follow up of 24 months (range 21-29 months). At the end of treatment 52% presented grade 0 acute toxicity 39% had grade 1 and 9% had grade 2. At 6 months with all the patients assessed there were 34% case of grade 1 subacute toxicity and 6% of grade 2. At 12 months 43% and 3% of patients presented with clinical grade 1 and grade 2 fibrosis respectively and 5% presented grade 1 hyperpigmentation. The remaining patients were free of side effects. At 24 months, with 56 assessed, just 2 patients (3%) showed grade 2 of late fibrosis. The clinical results observed showed a reasonably good feasibility of the accelerated hypofractionated schedule in terms of acute, subacute and short-term late toxicity. This useful 13 fractions with a concomitant boost schedule seems, in selected patients, a biologically acceptable alternative to the traditional 30 days regime

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

    Energy Technology Data Exchange (ETDEWEB)

    Elam, S. (ed.)

    1977-04-01

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

  1. Radiation sensitizations at DNA-level by chemical and biological agents. Coordinated programme on improvement of radiotherapy of cancer using modifiers of radiosensitivity of cells

    International Nuclear Information System (INIS)

    Radiation sensitization by chemical agents at DNA level is discussed. Procaine, Halothan and Metronidazole showed no significant effect on unscheduled DNA synthesis (UDS) in mouse spleen cells, investigated by autoradiography and no effect on rejoining of DNA single strand breaks after gamma or UV irradiation. Oxyphenbutazon and prednisolone reduced the replicative DNA synthesis in vitro and in vivo but there was only little effect on DNA repair in the in vivo experiments. These two substances showed also a small reduction in poly(ADP-ribose) synthesis (PAR synthesis). 5-methoxypsoralen (5-MOP) and 8-methoxypsoralen (8-MOP) in combination with UV irradiation showed that 5-MOP was more toxic than mutagen, but induced much less DNA crosslinks than 8-MOP. Autoradiographic studies of radiation sensitization by biological agents showed significant inhibition of UDS in Yoshida tumor cells after acute mycoplasma infection in rats. Nucleoid sedimentation studies showed only in the case of Yoshida tumor cells after mycoplasma infection a dramatic effect in the sedimentation behaviour. Sensitization of cells by changing chromatin structure was also studied. Benzamide, 3-NH2-benzamide, 3-Methoxybenzamide, Spermine, Theophyllin and Caffeine were tested in different concentrations on replicative DNA synthesis, UDS after UV irradiation and PAR synthesis Chinese hamster ovary cells. 5-Methoxybenzamide was the strongest sensitizer and inhibitor of the PAR synthesis, and was used in further experiments. Results of KFA Juelich on sensitization of a mamma-adenocarcinoma EO 771 on C57 B1 mice are given. Replicative DNA synthesis, DNA repair and PAR synthesis were compared in spleen cells and adenocarcinoma cells after treatment with 5-Methoxybenzamide. An inhibitory effect on UDS could be shown only in adenocarcinoma cells but not in the mice spleen cells

  2. Which Is the Optimal Biologically Effective Dose of Stereotactic Body Radiotherapy for Stage I Non–Small-Cell Lung Cancer? A Meta-Analysis

    International Nuclear Information System (INIS)

    Purpose: To assess the relationship between biologically effective dose (BED) and efficacy of stereotactic body radiation therapy (SBRT) and to explore the optimal BED range for Stage I non–small-cell lung cancer (NSCLC). Methods and Materials: Eligible studies were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2010. According to the quartile of included studies, BED was divided into four dose groups: low (146 Gy). To obtain pooled estimates of overall survival (OS), cancer-specific survival (CSS), and local control rate (LCR), data were combined in a random effect model. Pooled estimates were corrected for the percentage of small tumors (<3 cm). Results: Thirty-four observational studies with a total of 2,587 patients were included in the meta-analysis. Corrected pooled estimates of 2- or 3-year OS in the medium BED (76.1%, 63.5%) or the medium to high BED (68.3%, 63.2%) groups were higher than in the low (62.3%, 51.9%) or high groups (55.9%, 49.5%), respectively (p ≤ 0.004). Corrected 3-year CSS in the medium (79.5%), medium to high (80.6%), and high groups (90.0%) were higher than in the low group (70.1%, p = 0.016, 0.018, 0.001, respectively). Conclusion: The OS for the medium or medium to high BED groups were higher than those for the low or high BED group for SBRT in Stage I NSCLC. The medium or medium to high BED (range, 83.2 146 Gy) for SBRT may currently be more beneficial and reasonable in Stage I NSCLC.

  3. Radiotherapy of anal carcinomas

    International Nuclear Information System (INIS)

    Report is given on radiotherapy of anal carcinomas. Own experiences and a review of the recent literature are presented. Prior to surgery radiotherapy with high energy electrons in combination with chemotherapy is in the foreground. Especially in cloacogenous carcinoma no residual tumor was found after preliminary irradiation. Our recommended conception of post-operative radiotherapy of the regional lymphatic draining vessels is outlined. (orig./MG)

  4. Antiproton radiotherapy

    CERN Document Server

    Bassler, Niels; Beyer, Gerd; DeMarco, John J.; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Iwamoto, Keisuke S.; Jakel, Oliver; Knudsen, Helge V.; Kovacevic, Sandra; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen B.à; Solberg, Timothy D.; Sørensen, Brita S.; Vranjes, Sanja; Wouters, Bradly G.; Holzscheiter, Michael H.

    2008-01-01

    Antiprotons are interesting as a possible future modality in radiation therapy for the following reasons: When fast antiprotons penetrate matter, protons and antiprotons have near identical stopping powers and exhibit equal radiobiology well before the Bragg-peak. But when the antiprotons come to rest at the Bragg-peak, they annihilate, releasing almost 2 GeV per antiproton–proton annihilation. Most of this energy is carried away by energetic pions, but the Bragg-peak of the antiprotons is still locally augmented with ∼20–30 MeV per antiproton. Apart from the gain in physical dose, an increased relative biological effect also has been observed, which can be explained by the fact that some of the secondary particles from the antiproton annihilation exhibit high-LET properties. Finally, the weakly interacting energetic pions, which are leaving the target volume, may provide a real time feedback on the exact location of the annihilation peak. We have performed dosimetry experiments and investigated the rad...

  5. Quality Assurance in Radiotherapy

    Science.gov (United States)

    Mckenzie, Alan

    A common feature of the Radiotherapy Centres where there have been major accidents involving incorrect radiotherapy treatment is that they did not operate good Quality Assurance systems. A Quality Assurance system is sometimes called a Quality Management system, and it is designed to give assurance that quality standards are being met. One of the "spin offs" from operating a Quality Management system is that it reduces the likelihood of a radiotherapy accident. A detailed account of how to set up a quality system in radiotherapy has been given in an ESTRO booklet.2

  6. Radiotherapy of Cervical Cancer.

    Science.gov (United States)

    Vordermark, Dirk

    2016-01-01

    Curative-intent radical radiotherapy of cervical cancer consists of external-beam radiotherapy, brachytherapy, and concomitant chemotherapy with cisplatin. For each element, new developments aim to improve tumor control rates or treatment tolerance. Intensity-modulated radiotherapy (IMRT) has been shown to reduce gastrointestinal toxicity and can be used to selectively increase the radiotherapy dose. Individualized, image-guided brachytherapy enables better adaptation of high-dose volumes to the tumor extension. Intensification of concomitant or sequential systemic therapy is under evaluation. PMID:27614991

  7. Paradigm Shift in Radiation Biology/Radiation Oncology-Exploitation of the "H₂O₂ Effect" for Radiotherapy Using Low-LET (Linear Energy Transfer) Radiation such as X-rays and High-Energy Electrons.

    Science.gov (United States)

    Ogawa, Yasuhiro

    2016-01-01

    Most radiation biologists/radiation oncologists have long accepted the concept that the biologic effects of radiation principally involve damage to deoxyribonucleic acid (DNA), which is the critical target, as described in "Radiobiology for the Radiologist", by E.J. Hall and A.J. Giaccia [1]. Although the concepts of direct and indirect effects of radiation are fully applicable to low-LET (linear energy transfer) radioresistant tumor cells/normal tissues such as osteosarcoma cells and chondrocytes, it is believed that radiation-associated damage to DNA does not play a major role in the mechanism of cell death in low-LET radiosensitive tumors/normal tissues such as malignant lymphoma cells and lymphocytes. Hall and Giaccia describe lymphocytes as very radiosensitive, based largely on apoptosis subsequent to irradiation. As described in this review, apoptosis of lymphocytes and lymphoma cells is actually induced by the "hydrogen peroxide (H₂O₂) effect", which I propose in this review article for the first time. The mechanism of lymphocyte death via the H₂O₂ effect represents an ideal model to develop the enhancement method of radiosensitivity for radiation therapy of malignant neoplasms. In terms of imitating the high radiosensitivity of lymphocytes, osteosarcoma cells (representative of low-LET radioresistant cells) might be the ideal model for indicating the conversion of cells from radioresistant to radiosensitive utilizing the H₂O₂ effect. External beam radiation such as X-rays and high-energy electrons for use in modern radiotherapy are generally produced using a linear accelerator. We theorized that when tumors are irradiated in the presence of H₂O₂, the activities of anti-oxidative enzymes such as peroxidases and catalase are blocked and oxygen molecules are produced at the same time via the H₂O₂ effect, resulting in oxidative damage to low-LET radioresistant tumor cells, thereby rendering them highly sensitive to irradiation. In this

  8. Paradigm Shift in Radiation Biology/Radiation Oncology—Exploitation of the “H2O2 Effect” for Radiotherapy Using Low-LET (Linear Energy Transfer Radiation such as X-rays and High-Energy Electrons

    Directory of Open Access Journals (Sweden)

    Yasuhiro Ogawa

    2016-02-01

    Full Text Available Most radiation biologists/radiation oncologists have long accepted the concept that the biologic effects of radiation principally involve damage to deoxyribonucleic acid (DNA, which is the critical target, as described in “Radiobiology for the Radiologist”, by E.J. Hall and A.J. Giaccia [1]. Although the concepts of direct and indirect effects of radiation are fully applicable to low-LET (linear energy transfer radioresistant tumor cells/normal tissues such as osteosarcoma cells and chondrocytes, it is believed that radiation-associated damage to DNA does not play a major role in the mechanism of cell death in low-LET radiosensitive tumors/normal tissues such as malignant lymphoma cells and lymphocytes. Hall and Giaccia describe lymphocytes as very radiosensitive, based largely on apoptosis subsequent to irradiation. As described in this review, apoptosis of lymphocytes and lymphoma cells is actually induced by the “hydrogen peroxide (H2O2 effect”, which I propose in this review article for the first time. The mechanism of lymphocyte death via the H2O2 effect represents an ideal model to develop the enhancement method of radiosensitivity for radiation therapy of malignant neoplasms. In terms of imitating the high radiosensitivity of lymphocytes, osteosarcoma cells (representative of low-LET radioresistant cells might be the ideal model for indicating the conversion of cells from radioresistant to radiosensitive utilizing the H2O2 effect. External beam radiation such as X-rays and high-energy electrons for use in modern radiotherapy are generally produced using a linear accelerator. We theorized that when tumors are irradiated in the presence of H2O2, the activities of anti-oxidative enzymes such as peroxidases and catalase are blocked and oxygen molecules are produced at the same time via the H2O2 effect, resulting in oxidative damage to low-LET radioresistant tumor cells, thereby rendering them highly sensitive to irradiation. In this

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

    International Nuclear Information System (INIS)

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

  10. 3.4 Radiotherapy

    Science.gov (United States)

    Kramer, H.-M.; Selbach, H.-J.; Vatnitsky, S.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '3.4 Radiotherapy' of the Chapter '3 Dosimetry in Diagnostic Radiology and Radiotherapy' with the contents:

  11. Training logbook for radiotherapy.

    NARCIS (Netherlands)

    Hunter, R.; Maciejewski, B.; Leer, J.W.H.; Kinay, M.; Heeren, G.

    2004-01-01

    AIM: To develop a structured logbook for trainees in the medical specialty of radiotherapy with Europe that records the increasing experience throughout their training period. MATERIAL AND METHODS: A working party appointed by the European Board of Radiotherapy developed a draft version of a Europea

  12. Antitumor radiotherapy in children

    International Nuclear Information System (INIS)

    The philosophy is outlined of the therapy of malignant tumors in children, including Hodgkin type lymphomas and non-Hodgkin tumors, such as Wilm's tumor. The role of radiotherapy is defined and discussed in the comprehensive management of children using a combined radiotherapy-chemotherapy system. (L.O.). 5 refs

  13. [Radiotherapy of skin cancers].

    Science.gov (United States)

    Hennequin, C; Rio, E; Mahé, M-A

    2016-09-01

    The indications of radiotherapy for skin cancers are not clearly defined because of the lack of randomised trials or prospective studies. For basal cell carcinomas, radiotherapy frequently offers a good local control, but a randomized trial showed that surgery is more efficient and less toxic. Indications of radiotherapy are contra-indications of surgery for patients older than 60, non-sclerodermiform histology and occurring in non-sensitive areas. Adjuvant radiotherapy could be proposed to squamous cell carcinomas, in case of poor prognostic factors. Dose of 60 to 70Gy are usually required, and must be modulated to the size of the lesions. Adjuvant radiotherapy seems beneficial for desmoplastic melanomas but not for the other histological types. Prophylactic nodal irradiation (45 to 50Gy), for locally advanced tumours (massive nodal involvement), decreases the locoregional failure rate but do not increase survival. Adjuvant radiotherapy (50 to 56Gy) for Merckel cell carcinomas increases also the local control rate, as demonstrated by meta-analysis and a large epidemiological study. Nodal areas must be included, if there is no surgical exploration (sentinel lymph node dissection). Kaposi sarcomas are radiosensitive and could be treated with relatively low doses (24 to 30Gy). Also, cutaneous lymphomas are good indications for radiotherapy: B lymphomas are electively treated with limited fields. The role of total skin electron therapy for T-lymphomas is still discussed; but palliative radiotherapy is very efficient in case of cutaneous nodules. PMID:27522189

  14. To understand radiotherapy

    International Nuclear Information System (INIS)

    Dealing with the use of radiotherapy for adults, this guide indicates when a radiotherapy is suggested, how it acts, how the treatment is chosen, which are the professionals involved. It describes how an external radiotherapy takes place and its various techniques, the different types of side effects (general, specific to the treated zone, late effects). It indicates which organs can be treated by curie-therapy, the different curie-therapy treatment modalities, how a curie-therapy takes place and which are its side effects. It outlines how to better cope with radiotherapy (how to be supported, the important role of relatives, everyday life questions, rights). It indicates and comments the different measures adopted for the safety and quality of radiotherapy

  15. Sorafenib and radiotherapy association for hepatocellular carcinoma; Sorafenib et radiotherapie dans le carcinome hepatocellulaire

    Energy Technology Data Exchange (ETDEWEB)

    Girard, N. [Service de pneumologie, hopital Louis-Pradel, hospices Civils de Lyon, 28, avenue du Doyen-Jean-Lepine, 69500 Bron (France); UMR 754, universite Claude-Bernard Lyon 1, 43, boulevard du 11-novembre-1918, 69622 Villeurbanne cedex (France); Mornex, F. [UMR 754, universite Claude-Bernard Lyon 1, 43, boulevard du 11-novembre-1918, 69622 Villeurbanne cedex (France); Departement de radiotherapie-oncologie, centre hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Benite cedex (France)

    2011-02-15

    Conformal radiotherapy is a promising therapeutic strategy for hepatocellular carcinoma (HCC), producing local control rates above 90% within the radiation beam. However, survival after radiotherapy remains limited by the high frequency of intra- and extra-hepatic recurrences, which occurs in 40-50 and 20-30% of cases, respectively. Sorafenib (BAY43-9006, Nexavar; Bayer, West Haven, CT) is a small molecule inhibitor that demonstrated potent activity to target v-raf murine sarcoma oncogene homologue B1 (BRAF) and VEGFR tyrosine kinases. Sorafenib is the only drug that demonstrated effectiveness to increase overall survival in advanced or metastatic hepatocellular carcinoma. The rationale to combine radiotherapy with sorafenib is the following: (1) targeting RAS-RAF-MAPK and VEGFR signaling pathways, which are specifically activated after exposure to radiation, and responsible for radio-resistance phenomenon; (2) enhancing the oxygen effect through normalization of the surviving tumor vasculature; and (3) synchronization of the cell cycle. Sorafenib and radiotherapy represent complementary strategies, as radiotherapy may be useful to prolong the effect of sorafenib through control of the macroscopic disease, when sorafenib may target latent microscopic disease. Sorafenib and radiotherapy associations are thus based on a relevant biological and clinical rationale and are being evaluated in ongoing phase I-II trials. (authors)

  16. Auger Emitter Based Radiotherapy- A Possible New Treatment for Cancer

    DEFF Research Database (Denmark)

    Fredericia, Pil; Groesser, Torsten; Severin, Gregory; Köster, U.; Jensen, Andreas Tue Ingemann; Jensen, Mikael

    2014-01-01

    Cancer is a major cause of mortality worldwide (1). A large fraction of cancer patients undergo external radiotherapy, delivering a lethal dose of radiation to the patient’s tumour(s). The main problem with this approach is the collateral damage caused to healthy, surrounding tissue and the side...... damage produced by Low-LET radiation used in current radiotherapy (2-3) Considerable efforts have been made in the past twenty years to develop Auger emitter-based radiotherapy However, previous studies lack precise measurement of RBE, which is the fundamental factor defining the relationship between...... local radiation dose and biological damage done for the given Auger emitter, thereby brought the development to a halt. We believe we have the techniques to quantify the biological damage done for a given Auger emitter and thereby pushing the development of Auger emitterbased radiotherapy into reality...

  17. Advances of Precise Radiotherapy for Lung Cancer

    OpenAIRE

    Xin WANG; Xu, Feng; Wei, Yuquan

    2011-01-01

    At present lung tumor radiation therapy has entered the accurate radiotherapy era. Precise radiotherapy includes intensity modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT) and stereotactic body radiotherapy (SBRT). During the process of implementing precise radiotherapy, these problems should be fully considered to ensure executing precise radiotherapy accurately: patient positioning, controlling of the lung tumor motion, selecting of image techniques, PTV margin, dose prescrip...

  18. Experimental radiotherapy and clinical radiobiology. Vol. 22. Proceedings

    International Nuclear Information System (INIS)

    The proceedings of the 25th symposium on experimental radiotherapy and clinical radiobiology include papers on the following issues: radiotherapy individualization based on imaging; pre-clinic imaging and new experimental methods; methods and models, micromilieu and metabolism, combined therapy; secondary tumors following radiotherapy; radiogenic effects in normal tissue; resistance mechanism of tumors and normal tissue; personalized radio-oncology - which biological data are needed; pre-clinic and personalized radio-oncology; biomarkers - pre-clinic and translational; translational examinations for personalized radio-oncology.

  19. Foundations in radiological protection and radiotherapy

    International Nuclear Information System (INIS)

    The work is divided in three parts. The part 1 are a brief abstrac of some important concepts related with the cells. The part 2 speak in general of the biological effects of the ionizing radiations according to the recommendations of the international commission of radiological protection. The part 3 refer to radiobiological calculations applying the quadratic lineal pattern to the radiotherapy. These calculations are important in view of the fact that they are applied for the introduction of new outlines of treatments

  20. DICOM in Radiotherapy

    Directory of Open Access Journals (Sweden)

    A. Nikfarjam

    2007-08-01

    Full Text Available Noticeable development in achieving data from patients is acquired by means of designing a system that connects these systems: imaging, archive and monitoring systems. When several imaging devices work based on DICOM standard; they can connect to each other without any interface. There are many applications for DICOM standard in radiotherapy; however its main usage is in imaging. It has other applications such as RT Structure Set, RT Dose, RT Plan and RT Brachy Treatment. "nNow DICOM is a complete and widespread standard to use in radiotherapy. Most of the radiotherapy machines have ability to use DICOM. Before installing a new Linac, it is necessary to predict all aspects of DICOM standard in this device. Therefore, as regards to entrance of 12 Linac to Iran, it is important to have enough knowledge about it. This article is a review about development of DICOM in radiotherapy. We try to stress on DICOM applications and abstain from technological agenda.

  1. Radiotherapy cure: safety

    International Nuclear Information System (INIS)

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

  2. Radiotherapy: an interactive learning tool

    International Nuclear Information System (INIS)

    The program is primarily intended for radiological medical technicians, student nurses, students of medicine and physics, and doctors. It is designed as a tool for vocational training and further training and gives comprehensive insight into the daily routines of a radiotherapy unit. The chapters deal with: fundamental biological aspects - fundamental physical aspects - radiation sources and irradiation systems - preparatory examinations - therapies and concepts - irradiation planning - irradiation performance - termination of irradiation treatment. For every page displayed, spoken texts and written, on-screen keywords, illustrations, animated sequences and a large number of videos have been combined in a way easy to digest. The software of the program permits handling also by learners less familiar with computer-based learning. (orig./)

  3. Experimental radiotherapy and clinical radiobiology. Vol. 18. Proceedings

    International Nuclear Information System (INIS)

    The proceedings on experimental radiotherapy and clinical radiobiology contain two review articles (prediction of normal tissue reactions after radiotherapy, ?H2AX foci as a marker for DNA double-strand breaks) and 34 contributions to the following topics: Hypoxia and molecular mechanisms of radiation resistance; biological imaging of the tumor micromilieu; DNA repair, genomic instability and carcerogenesis; molecular factors of radiation resistance; actual controversial discussion on possible irradiation caused metastasis risk enhancement; EGFR inhibition and irradiation; biology of experimental radiation/ normal tissue toxicity

  4. Postoperative radiotherapy of prostate cancer; Radiotherapie postoperatoire des cancers de la prostate

    Energy Technology Data Exchange (ETDEWEB)

    Richaud, P.; Sargos, P.; Henriques Figueiredo, B. [Service de radiotherapie, centre regional de lutte contre le cancer, institut Bergonie, 33 - Bordeaux (France); Latorzeff, I. [Service de radiotherapie, clinique Pasteur, 31 - Toulouse (France); Mongiat-Artus, P. [Service d' urologie, hopital Saint-Louis, 75 - Paris (France); Houede, N. [Service d' oncologie medicale, centre regional de lutte contre le cancer, institut Bergonie, 33 - Bordeaux (France); Salomon, L. [Service d' urologie, 94 - Creteil (France); Wallerand, H. [Service d' urologie, faculte de medecine Victor-Segalen, CHU Pellegrin-Tripode, 33 - Bordeaux (France)

    2010-10-15

    After radical prostatectomy, the risk of biological recurrence at 5 years varies from 10 to 40 % and this natural evolution of the disease has led radiation therapy being proposed as a supplement to surgery. When the recurrence risk is essentially local, supplementary radiotherapy is justified in the aim of improving biological recurrence-free survival, local control, metastasis-free survival and specific and global survival, while respecting patient quality of life. Three recent studies, EORTC 22911, ARO 9602 and SWOG 8794 found a similar advantage for biological recurrence-free survival without higher major additional toxicity. However, only the SWOG 8794 study found a significant improvement for metastasis-free survival and global survival. In an adjuvant setting, the optimal moment to propose this postoperative radiotherapy remains uncertain: should it be proposed systematically to all pT3 R1 patients, running the risk of pointlessly treating patients who will never recur, or should it only be proposed at recurrence? The GETUG AFU 17 trial will provide answers to the question of the optimal moment for postoperative radiotherapy for pT3-4 R1 pN0 Nx patients with the objective of comparing an immediate treatment to a differed early treatment initiated at biological recurrence. (authors)

  5. Advice concerning radiotherapy

    International Nuclear Information System (INIS)

    Dutch National cancer incidence figures were calculated by using the reliable data on cancer incidence in the Eindhoven area and population forecasts and information obtained from the Central Bureau of Statistics. Several radiotherapy departments suffer from under capacity (a lack of resources and understaffing). Data have also shown that 35% of cancer patients receive radiotherapy, instead of 50%. Calculations have been made by the committee on the present and future needs with regard to equipment and staff. In 1983, the number of megavoltage therapy units amounted to 38, but should have been 65. It should be 80 in 1990 and 90 in 2000. Since building and installing such equipment is a lengthy process a considerable effort is needed to make up for the arrears. The committee advocates the extension of the system of regional cooperation in cancer care (comprehensive cancer centres), in which radiotherapy departments play a crucial role. Working parties from the committee provided a comprehensive description of current radiotherapy practice with reference to physical, technical, clinical and management aspects. Another working party assessed the results of cancer treatment with regard to many different tumour sites. Recent and expected developments were analysed or indicated. The Radiotherapy Committee commissioned an external team to conduct a project to achieve a picture of future developments using methods different to those of the committee's. An interim advice has been added on this subject. (Auth.)

  6. Experimental radiotherapy and clinical radiobiology. Vol. 20. Proceedings; Experimentelle Strahlentherapie und Klinische Strahlenbiologie. Bd. 20. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Michael; Dahm-Daphi, Jochen; Dikomey, Ekkehard; Petersen, Cordula; Rodemannn, Hans-Peter; Zips, Daniel (eds.)

    2011-07-01

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

  7. Chemical modifiers of radiotherapy

    International Nuclear Information System (INIS)

    Only two groups, anticancer drugs and radiosensitizers are discussed among many groups of chemical modifiers. In combined radiotherapy (RT) with chemotherapy (CT), sequential administration seems to be superior to concomitant administration, because simultaneous use enhances intensively normal tissue damage. In sequential administration, interruption of CT during RT causes growth of distant metastases. So, alternating scheme of RT and CT is proposed and evaluated clinically. Hypoxic cell sensitizers including well-known misonidazole and PLDR inhibitors (Ara-A etc.) are promising in radiotherapy. They should be used intermittently two or three times during RT in order to avoid neurotoxicity of misonidazole. (author) 70 refs

  8. Xerostomia induced by radiotherapy

    Directory of Open Access Journals (Sweden)

    Alimi D

    2015-08-01

    Full Text Available David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have residual salivary gland function. Unfortunately, it is well established that in most cases radiotherapy destroys most of the salivary gland and associated salivary secretions.     

  9. Carbon ion radiotherapy for pancreatic cancer

    International Nuclear Information System (INIS)

    The Heavy Ion Medical Accelerator in Chiba (HIMAC) is the world's first heavy ion accelerator complex dedicated to medical use in a hospital environment. Carbon ion therapy offers the potential advantages of improved dose localization and enhanced biological effects. It has been suggested that carbon ion therapy is effective against radioresistant pancreatic cancer. In April 2000, clinical studies examining the treatment of pancreatic cancer with carbon ions were begun at the HIMAC. As of February 2010, 48 patients treated with preoperative carbon ion radiotherapy and 89 patients treated for locally advanced pancreatic cancer were enrolled into the clinical trials. Both protocols are still ongoing. The interim results of these clinical trials suggest that carbon ion radiotherapy provides good local control and offers a survival advantage for patients with otherwise hard to cure pancreatic cancer, without unacceptable morbidity. (author)

  10. Advances of Precise Radiotherapy for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Xin WANG

    2011-11-01

    Full Text Available At present lung tumor radiation therapy has entered the accurate radiotherapy era. Precise radiotherapy includes intensity modulated radiotherapy (IMRT, image-guided radiotherapy (IGRT and stereotactic body radiotherapy (SBRT. During the process of implementing precise radiotherapy, these problems should be fully considered to ensure executing precise radiotherapy accurately: patient positioning, controlling of the lung tumor motion, selecting of image techniques, PTV margin, dose prescription and reporting, arrangement of beams, controlling of dose volume and treatment delivering.

  11. Erythropoietin and radiotherapy; Erythropoietine et radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Le Fur, E.; Albarghach, M.N.; Pradier, O. [CHU de Morvan, Dept. de radiotherapie, 29 - Brest (France)

    2010-01-15

    Erythropoietin (E.P.O.) is a glycoprotein hormone. This hormone is a growth factor for red blood cells precursors in the bone marrow. The decrease of oxygen partial pressure, a reduced number of erythrocytes caused by bleeding or excessive destruction, or increased tissues oxygen requirements lead to increased secretion of E.P.O.. Its action takes place on bone marrow erythroblastic cells through specific receptors. E.P.O. stimulates the proliferation of red cell precursors stem cells in the bone marrow, thus increasing their production in one to two weeks. The effectiveness of E.P.O. at increasing haemoglobin and improving patients quality of life has been demonstrated by several studies. However, its use in radiotherapy remains controversial. While tumour hypoxia caused by anaemia is a factor of radio resistance and thus a source of local failure, tumour expression of E.P.O. receptors presents a significant risk for tumour progression and neo-angiogenesis, which would be increased during the administration of E.P.O.. The purpose of this article is to answer the question: is there a place for E.P.O. in combination with radiotherapy in the management of cancer?

  12. Quality indicators in radiotherapy

    International Nuclear Information System (INIS)

    Background and purpose: There is a widespread and increasing tendency to develop hospital performance indicators in the field of accreditation/certification systems and quality benchmarking. A study has been undertaken to develop a set of performance indicators for a typical radiotherapy Centre and to evaluate their ability to provide a continuous quality improvement. Materials and methods: A working group consisting of radiation oncologists, medical physicists and radiation technologists under the coordination of experts in health technology assessment has elaborated a set of general indicators able to monitor performances and the quality level of a typical radiotherapy Centre. The work has been carried out through four steps: a preliminary set of indicators was selected; data on these indicators were collected in a number of Italian radiotherapy Centres and medical physics Services; problems in collection and analysis of data were discussed; a final set of indicators was developed. Results: A final set of 13 indicators is here presented. They concern general structural and/or operational features, health physics activities and accuracy and technical complexity of the treatment. Conclusions: The indicators tested in a few Italian Centres of radiotherapy and medical physics Services are now ready to be utilized by a larger community

  13. Bowel disease after radiotherapy

    International Nuclear Information System (INIS)

    The clinical presentation, operative findings and outcome in 40 patients who required surgery for bowel disease after radiotherapy are presented. The type of presentation varied according to the time after radiotherapy. In the first month, many patients had a proctitis but none required surgery. Five patients were operated on within one month, 2 for radiation-induced acute ileitis and 3 for exacerbations of pre-existing disease (diverticular disease 2, ulcerative colitis 1). The commonest time of presentation was between 3 and 18 months after radiotherapy, when 20 patients needed surgery for bowel disease caused by radiation-induced local ischaemia. Twelve of these patients had chronic perforation, 6 had severe rectal bleeding and 2 had painful anorectal ulceration. Fifteen patients presented between 2 and 24 years after radiotherapy, usually with incomplete intestinal obstruction due to a fibrous stricture, but 2 patients had rectal carcinoma. Wide resection of the involved bowel was the principal method of treatment but any anastomosis was protected by a proximal defunctioning stoma. There was no operative mortality but 10 patients have died subsequently. The danger of dismissing these patients as having incurable malignancy is stressed because, although the condition is infrequent, it is usually amenable to adequate surgery. (author)

  14. Nanoparticle-guided radiotherapy

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing for simult...

  15. Radiotherapy treatment planning

    International Nuclear Information System (INIS)

    A teaching text on external beam radiotherapy treatment planning is presented. Chapters are included on machines, radiation units, the physics of a single radiation field, the multiple-field isodose curve pattern, electron beam therapy, manual addition of isodose curves and dose calculation methods. (U.K.)

  16. Quality assurance in radiotherapy

    International Nuclear Information System (INIS)

    Good radiotherapy results and safety of treatment require the radiation to be optimally applied to a specified target area and the correct dose. According to international recommendations, the average uncertainty in therapeutic dose should not exceed 5%. The need for high precision in therapeutic dose requires quality assurance covering the entire radiotherapy process. Besides the physical and technical characteristics of the therapy equipment, quality assurance must include all radiotherapy equipment and procedures that are significant for the correct magnitude and precision of application of the therapeutic dose. The duties and responsibilities pertaining to various stages of treatment must also be precisely defined. These requirements may be best implemented through a quality system. The general requirements for supervision and quality assurance of medical radiation apparatus are prescribed in section 40 of the Radiation Act (592/1991, amendment 1142/1998) and in sections 18 and 32 of the Decree of the Ministry of Social Affairs and Health on the medical use of radiation (423/2000). Guide ST 2.2 imposes requirements on structural radiation shielding of radiotherapy equipment and the premises in which it is used, and on warning and safety arrangements. Guide ST 1.1 sets out the general safety principles for radiation practices and regulatory control procedure for the use of radiation. Guide ST 1.6 provides general requirements for operational measures in the use of radiation. This Guide sets out the duties of responsible parties (the party running a radiation practice) in respect of arranging and maintaining radiotherapy quality assurance. The principles set out in this Guide and Guide ST 6.3 may be applied to radionuclide therapy

  17. INL Advanced Radiotherapy Research Program Annual Report 2004

    Energy Technology Data Exchange (ETDEWEB)

    James Venhuizen

    2005-06-01

    This report summarizes the activities and major accomplishments for the Idaho National Laboratory Advanced Radiotherapy Research Program for calendar year 2004. Topics covered include boron analysis in biological samples, computational dosimetry and treatment planning software development, medical neutron source development and characterization, and collaborative dosimetry studies at the RA-1 facility in Buenos Aires, Argentina.

  18. Monte Carlo role in radiobiological modelling of radiotherapy outcomes

    Science.gov (United States)

    El Naqa, Issam; Pater, Piotr; Seuntjens, Jan

    2012-06-01

    Radiobiological models are essential components of modern radiotherapy. They are increasingly applied to optimize and evaluate the quality of different treatment planning modalities. They are frequently used in designing new radiotherapy clinical trials by estimating the expected therapeutic ratio of new protocols. In radiobiology, the therapeutic ratio is estimated from the expected gain in tumour control probability (TCP) to the risk of normal tissue complication probability (NTCP). However, estimates of TCP/NTCP are currently based on the deterministic and simplistic linear-quadratic formalism with limited prediction power when applied prospectively. Given the complex and stochastic nature of the physical, chemical and biological interactions associated with spatial and temporal radiation induced effects in living tissues, it is conjectured that methods based on Monte Carlo (MC) analysis may provide better estimates of TCP/NTCP for radiotherapy treatment planning and trial design. Indeed, over the past few decades, methods based on MC have demonstrated superior performance for accurate simulation of radiation transport, tumour growth and particle track structures; however, successful application of modelling radiobiological response and outcomes in radiotherapy is still hampered with several challenges. In this review, we provide an overview of some of the main techniques used in radiobiological modelling for radiotherapy, with focus on the MC role as a promising computational vehicle. We highlight the current challenges, issues and future potentials of the MC approach towards a comprehensive systems-based framework in radiobiological modelling for radiotherapy.

  19. Radiotherapy of bronco-pulmonary cancer; Radiotherapie des cancers brochopulmonaires

    Energy Technology Data Exchange (ETDEWEB)

    Bourry, N.; Millardet, C.; Lapeyre, M.; Verrelle, P.; Gross, E.; Champeaux-Orange, E.; Lahbabi, K.; Galland, S.; Chomy, F.; Lagarde, P.; Blanchard, P

    2007-11-15

    Six oral communications as follow: tomography by positron emission with {sup 18}F-FDG and target volume determination in the non at small cells bronchi cancers: interest and limit; adjuvant radiotherapy in the non at small cells pulmonary cancers; pulmonary stereotaxic radiotherapy; the chemoradiotherapy of locally evolved bronco-pulmonary cancers; the mesothelioma: place of radiotherapy; predictive factors of the toxicity and the care of complications of thorax irradiation. (N.C.)

  20. Oral mucositis. A complication of radiotherapy

    International Nuclear Information System (INIS)

    Oral mucositis is a complication of head and neck radiotherapy. It is understood what causes the inflammation and what biological tissue changes occur, however, a definite cure for oral mucositis has not yet been found. Supportive treatments, analgesics, antimicrobials and anti-inflammatory agents have been prescribed, none of which has been a thorough measure of treatment. An effective cure for oral mucositis is still in the midst of scientific research. In the interim local palliative treatments will help to alleviate the patients', debilitating symptoms

  1. Ridge filter design for carbon radiotherapy

    International Nuclear Information System (INIS)

    The design of a ridge filter intended for forming the uniform spread-out Bragg peak within a tumor at carbon radiotherapy is described. The computation of the ridge filter shape was carried out by an analytical algorithm and tested by MC simulation (GEANT4 code). Two kinds of the ridge filter were considered: stationary and movable. The influence on a ridge filter shape of the carbon beam energy and type of relative biological effectiveness dependence on the carbon ion linear energy transfer in tissue were examined

  2. External audit in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Quality audit forms an essential part of any comprehensive quality assurance programme. This is true in radiotherapy generally and in specific areas such as radiotherapy dosimetry. Quality audit can independently test the effectiveness of the quality system and in so doing can identify problem areas and minimize their possible consequences. Some general points concerning quality audit applied to radiotherapy are followed by specific discussion of its practical role in radiotherapy dosimetry, following its evolution from dosimetric intercomparison exercises to routine measurement-based on-going audit in the various developing audit networks both in the UK and internationally. Specific examples of methods and results are given from some of these, including the Scottish+ audit group. Quality audit in radiotherapy dosimetry is now well proven and participation by individual centres is strongly recommended. Similar audit approaches are to be encouraged in other areas of the radiotherapy process. (author)

  3. Radiotherapy of hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Gauwerky, F.

    1982-10-11

    The findings about the regular, spontaneous and complete regression of cavernous skin hemangiomas occurring in infants and those findings about the damaging effects due to ionising radiation - here particularly local growth disturbances - led to the development of very cautious diagnostic methods and to a considerate individual dosage and radiotherapy, which always takes into consideration the spontaneous regression tendency of the hemangiomas. However, a function-impairing localisation at the orifices, fulminant macrosomia, tendency to hemorrhages and poly-infection with superficial ulceration and even thrombopenic syndromes of the Kasabach-Merritt type may become necessary, urgent and also vital indications for a particular radiotherapy. For the sake of the patients, irradiation methods, which do not provoke any risk of radiation hazards, have to be preserved and applied in practice. Certainly further research and the nosologic nature of hemangiomas is required. A general non-treatment of hemangiomas is refused.

  4. Nutrition and radiotherapy

    International Nuclear Information System (INIS)

    Full text: Radiation is a common method of treating large tumours, however one of the major problems in radiation therapy is the severe side effects that may limit its efficacy. Utilising nutrients can assist in the control of these side effects which will greatly enhance the quality of life of the patient plus improve the effectiveness of the radiation. Another controversial point regarding radiation and nutrition is the concurrent use of antioxidants and radiotherapy. The science literature is in agreement that supplementing with antioxidants after radiation is essential. In addition, most studies now show that antioxidants do not interfere with the efficacy of radiotherapy. These issues and suggestions for nutrients to assist during and after radiation will be discussed

  5. Radiotherapy for aggressive fibromatosis

    International Nuclear Information System (INIS)

    Purpose/Objective: To evaluate local control with radiotherapy for aggressive fibromatosis. Materials and Methods: Fifty-three patients with histologically confirmed aggressive fibromatosis were treated with radiotherapy at the University of Florida between March 1975 and June 1992. The minimum length of follow-up was 2 years; 88% of patients had follow-up for at least 5 years. Thirty-nine patients had lesions in an extremity and 14 patients had lesions in the trunk. Twenty-nine patients were treated for gross disease. Patients were treated with total doses between 35 Gy and 70 Gy; 83% of patients received 50 Gy to 60 Gy. Results: Local control was achieved in 23 of 29 patients (79%) treated for postoperative microscopic residual disease. Local control was achieved in 21 of 24 patients (88%) treated for gross disease; gross disease was controlled in 8 of 8 patients with previously untreated lesions, and in 13 of 16 patients treated for postoperative gross residual and recurrent disease. Overall, aggressive fibromatosis was locally controlled in 83% of treated patients. All 9 treatment failures occurred with extremity lesions 4 to 68 months after initiation of treatment. Of the 9 recurrences, 4 were out-of-field, 3 were in-field, and 4 occurred at the margin of the irradiated field. Salvage was successful in 8 of 9 patients in whom salvage was attempted with surgery alone or combined with postoperative radiotherapy. A functional limb was maintained in 38 of 39 patients with extremity or limb girdle lesions. The most serious complication of treatment was pathologic fracture, which occurred in 3 of 53 treated patients; all 3 fractures healed with conservative management. Conclusion: Radiotherapy is a valuable adjunct to surgery in the management of aggressive fibromatosis and can be used alone in patients with unresectable or inoperable disease

  6. Conformal radiotherapy: a glossary

    International Nuclear Information System (INIS)

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

  7. DICOM in Radiotherapy

    OpenAIRE

    A. Nikfarjam; E Ganjalikhan Hakemi; E. Negahbani; MR. Khajeaminian

    2007-01-01

    Noticeable development in achieving data from patients is acquired by means of designing a system that connects these systems: imaging, archive and monitoring systems. When several imaging devices work based on DICOM standard; they can connect to each other without any interface. There are many applications for DICOM standard in radiotherapy; however its main usage is in imaging. It has other applications such as RT Structure Set, RT Dose, RT Plan and RT Brachy Treatment. "nNow DICOM is ...

  8. Xerostomia induced by radiotherapy

    OpenAIRE

    Alimi, David

    2015-01-01

    David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have resi...

  9. Abstracts of the 28. annual meeting of the Austrian Radiation Oncology, Radiation Biology and Medical Radiation Physics Society (OeGRO 2011)

    International Nuclear Information System (INIS)

    The second part of the volume includes the abstracts of the 28th annual meeting of the Austrian Radiation Oncology, Radiation Biology and Medical Radiation Physics Society (OeGRO 2011), covering the following topics: extracranial stereotactic radiotherapy; brachytherapy, hyperthermia; radiotherapy side effects; psycho-oncology in radiotherapy; head-neck carcinomas; radiation source implants for carcinoma irradiation; MRI-supported adaptive radiotherapy; CT-guided radiotherapy; mammary carcinomas; prostate carcinomas; magnetic nanoparticles for future medical applications.

  10. Big Data Analytics for Prostate Radiotherapy

    Science.gov (United States)

    Coates, James; Souhami, Luis; El Naqa, Issam

    2016-01-01

    Radiation therapy is a first-line treatment option for localized prostate cancer and radiation-induced normal tissue damage are often the main limiting factor for modern radiotherapy regimens. Conversely, under-dosing of target volumes in an attempt to spare adjacent healthy tissues limits the likelihood of achieving local, long-term control. Thus, the ability to generate personalized data-driven risk profiles for radiotherapy outcomes would provide valuable prognostic information to help guide both clinicians and patients alike. Big data applied to radiation oncology promises to deliver better understanding of outcomes by harvesting and integrating heterogeneous data types, including patient-specific clinical parameters, treatment-related dose–volume metrics, and biological risk factors. When taken together, such variables make up the basis for a multi-dimensional space (the “RadoncSpace”) in which the presented modeling techniques search in order to identify significant predictors. Herein, we review outcome modeling and big data-mining techniques for both tumor control and radiotherapy-induced normal tissue effects. We apply many of the presented modeling approaches onto a cohort of hypofractionated prostate cancer patients taking into account different data types and a large heterogeneous mix of physical and biological parameters. Cross-validation techniques are also reviewed for the refinement of the proposed framework architecture and checking individual model performance. We conclude by considering advanced modeling techniques that borrow concepts from big data analytics, such as machine learning and artificial intelligence, before discussing the potential future impact of systems radiobiology approaches. PMID:27379211

  11. Big Data Analytics for Prostate Radiotherapy.

    Science.gov (United States)

    Coates, James; Souhami, Luis; El Naqa, Issam

    2016-01-01

    Radiation therapy is a first-line treatment option for localized prostate cancer and radiation-induced normal tissue damage are often the main limiting factor for modern radiotherapy regimens. Conversely, under-dosing of target volumes in an attempt to spare adjacent healthy tissues limits the likelihood of achieving local, long-term control. Thus, the ability to generate personalized data-driven risk profiles for radiotherapy outcomes would provide valuable prognostic information to help guide both clinicians and patients alike. Big data applied to radiation oncology promises to deliver better understanding of outcomes by harvesting and integrating heterogeneous data types, including patient-specific clinical parameters, treatment-related dose-volume metrics, and biological risk factors. When taken together, such variables make up the basis for a multi-dimensional space (the "RadoncSpace") in which the presented modeling techniques search in order to identify significant predictors. Herein, we review outcome modeling and big data-mining techniques for both tumor control and radiotherapy-induced normal tissue effects. We apply many of the presented modeling approaches onto a cohort of hypofractionated prostate cancer patients taking into account different data types and a large heterogeneous mix of physical and biological parameters. Cross-validation techniques are also reviewed for the refinement of the proposed framework architecture and checking individual model performance. We conclude by considering advanced modeling techniques that borrow concepts from big data analytics, such as machine learning and artificial intelligence, before discussing the potential future impact of systems radiobiology approaches. PMID:27379211

  12. Further Radiobiologic Modeling of Palliative Radiotherapy: Use of Virtual Trials

    International Nuclear Information System (INIS)

    Purpose: To study duration of response in palliative radiotherapy in a population of tumors. Methods and Materials: Models of dynamic changes in cell number with time were used to develop a function for the remission time (Trem) after palliative radiotherapy: Trem=(BED)/K -t1(1+(α.K)/z ), where BED is the biologically effective dose, t1 the duration of symptoms (i.e., the time between the onset of symptoms and the initiation of radiotherapy), K the daily BED repopulation equivalent, α the linear radiosensitivity parameter in the linear-quadratic model, and z the tumor regression rate. Results: Simulations of clinical trials show marked variations in remission statistics depending on the tumor characteristics and are highly compatible with the results of clinical trials. Dose escalation produces both a higher proportion and extended duration of remissions, especially in tumors with high α/β ratios and K values, but the predicted dose responses of acute and late side effects show that caution is necessary. The prospect of using particle beam therapy to reduce normal tissue radiation exposures or using hypoxic sensitizers to improve the tumor cell kill might significantly improve the results of palliative radiotherapy in carefully selected patients and could also be used for safer palliative re-treatments in patients with the potential for prolonged survival. The effect of tumor heterogeneity in determining palliative responses probably exceeds that in radical radiotherapy; as few as 100 patients in each treatment arm produce statistically unreliable results. Conclusions: Virtual trials of palliative radiotherapy can be useful to test the effects of competing schedules and better determine future strategies, including improved design of clinical trials as well as combinations of radiotherapy with other anticancer modalities

  13. Radiotherapy of presenile spinal osteoporosis

    International Nuclear Information System (INIS)

    Painfull conditions of presenile spinal osteoporosis may no longer respond to medication or physical therapy. Analgesic radiotherapy coupled with mild physical therapy and if necessary supported by orthopedic measures frequently results in pain relief and physical stability. Fifty-two cases of osteoporosis and osteoporotic spinal fractures illustrate how better longterm results are achieved by increasing the customary dosage and speeding up radiotherapy. (orig.)

  14. Tsallis entropy approach to radiotherapy treatments

    Science.gov (United States)

    Sotolongo-Grau, O.; Rodriguez-Perez, D.; Sotolongo-Costa, O.; Antoranz, J. C.

    2013-05-01

    The biological effect of one single radiation dose on a living tissue has been described by several radiobiological models. However, the fractionated radiotherapy requires to account for a new magnitude: time. In this paper we explore the biological consequences posed by the mathematical prolongation of a previous model to fractionated treatment. Nonextensive composition rules are introduced to obtain the survival fraction and equivalent physical dose in terms of a time dependent factor describing the tissue trend towards recovering its radioresistance (a kind of repair coefficient). Interesting (known and new) behaviors are described regarding the effectiveness of the treatment which is shown to be fundamentally bound to this factor. The continuous limit, applicable to brachytherapy, is also analyzed in the framework of nonextensive calculus. Here a coefficient that rules the time behavior also arises. All the results are discussed in terms of the clinical evidence and their major implications are highlighted.

  15. Radiotherapy for eyelid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saika, Kazumi [Yokohama City Univ. (Japan). School of Medicine

    2001-05-01

    Some studies on radiotherapy for eyelid cancer have been reported, but the optimal radiation doses for different histological types and tumor sizes have not been detailed. So I studied the optimal radiation doses in radiotherapy for eyelid cancer. The patients were fourteen and histological diagnoses were made on the basis of biopsies or surgery before radiotherapy. Surgical cut margins were positive in 10 cases. In 5 of these cases, tumors were visible. There were 9 sebaceous adenocarcinomas (SAC), 4 squamous cell carcinomas (SCC), and 1 basal cell carcinoma (BCC). In 13 of 14 cases, radiation was applied to eyelids in which tumor-surgical cut margin distances were 3 mm or less. The eyeballs were covered with lead or tungsten shields, and the eyelids were irradiated with a total dose of 50 to 66.6 Gy. In 5 cases, radiation was applied prophylactically for ipsilateral pre-auricle lymph node areas. 11 of 13 cases were locally controlled. I gave greater radiation doses for SAC than for SCC or BCC. I also gave greater doses for in visible tumors than for invisible ones. In the acute phase dermatitis, inflammation of the cornea, conjunctivitis, etc. occurred but they were mild. Later reactions were decreased cilia, dry eye, inflammation of cornea, conjunctivitis, discomfort of the scar, etc. Cataracts were also seen, but they were of senile origen. Because 81.8% of the tumors were controlled, this radiation method was useful with salvage therapies to select an optimal radiation dose according to the differences among histological types and tumor sizes. 60% of visible tumors were also controlled so I think that radical therapy using radiation alone is possible. (author)

  16. Radiotherapy of benign diseases

    International Nuclear Information System (INIS)

    Still today radiotherapy is of decisive relevance for several benign diseases. The following ones are briefly described in this introductory article: 1. Certain inflammatory and degenerative diseases as furuncles in the face, acute thrombophlebitis, recurrent sudoriparous abscesses, degenerative skeletal diseases, cervical syndrome and others; 2. rheumatic joint diseases; 3. Bechterew's disease; 4. primary presenile osteoporosis; 5. synringomyelia; 6. endocrine ophthalmopathy; 7. hypertrophic processes of the connective tissue; 8. hemangiomas. A detailed discussion and a profit-risk analysis is provided in the individual chapters of the magazine. (MG)

  17. Efficacy of bio-effect dose and overall treatment time in radiotherapy of carcinoma of cervix: a prospective study

    International Nuclear Information System (INIS)

    To study the response of tumour and early rectal complications in patients of cervical cancer who underwent radiotherapy on the basis of biological effective dose (BED) and overall treatment time (OTT)

  18. Breast cancer radiotherapy: controversies and prospectives

    Institute of Scientific and Technical Information of China (English)

    YU Jin-ming; WANG Yong-sheng

    2008-01-01

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

  19. DEGRO 2009. Radiation oncology - medical physics - radiation biology. Abstracts

    International Nuclear Information System (INIS)

    The special volume of the journal covers the abstracts of the DEGRO 2009 meeting on radiation oncology, medical physics, and radiation biology, covering the following topics: seldom diseases, gastrointestinal tumors, radiation reactions and radiation protection, medical care and science, central nervous system, medical physics, the non-parvicellular lung carcinomas, ear-nose-and throat, target-oriented radiotherapy plus ''X'', radio-oncology - young academics, lymphomas, mammary glands, modern radiotherapy, life quality and palliative radiotherapy, radiotherapy of the prostate carcinoma, imaging for planning and therapy, the digital documentation in clinics and practical experiences, NMR imaging and tomography, hadrons - actual status in Germany, urinal tract oncology, radiotoxicity

  20. Transverse tomography and radiotherapy

    International Nuclear Information System (INIS)

    This study was intended to delineate the indications for radiotherapy treatment-planning with the help of computerized axial tomography (C.T.) and transverse analog tomography (T.A.T.). Radiotherapy localisation procedures with the conventional method (simulator), with the CT-scanner and with the transverse analog tomograph (T.A.T., Simtomix, Oldelft) were compared. As criterium for evaluation differences in reconstruction drawing based on these methods were used. A certain method was judged ''superior'' to another if the delineation of the target volume was more accurate, if a better impression was gained of the site of (for irradiation) organs at risk, or if the localisation could only be performed with that method. The selected group of patients consisted of 120 patients for whom a reconstruction drawing in the transverse plane was made according to the treatment philosophy. In this group CT-assisted localisation was judged on 68 occasions superior to the conventional method. In a number of cases it was found that a ''standard'' change in a standard target volume, on the base of augmented anatomical knowledge, made the conventional method sufficient. The use of CT-scanner for treatment planning was estimated. For ca. 270/1000 new patients a CT-scan is helpful (diagnostic scan), for 140 of them the scan is necessary (planning scan). The quality of the anatomical information obtained with the T.A.T. does not yet fall within acceptable limits, but progress has been made. (Auth.)

  1. Experimental radiotherapy and clinical radiobiology. Vol. 22. Proceedings; Experimentelle Strahlentherapie und Klinische Strahlenbiologie. Bd. 25. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Michael; Krause, Mechthild [Universitaetsklinikum Technische Univ. Dresden (Germany). Klinik und Poliklinik fuer Strahlentherapie und Radiologie; Cordes, Nils [Universitaetsklinikum Technische Univ. Dresden (Germany). OncoRay - Nationales Zentrum fuer Strahlenforschung in der Radioonkologie; Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany); Petersen, Cordula [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie; Rodemann, H. Peter [Universitaetsklinikum Tuebingen (Germany). Sektion fuer Strahlenbiologie; Rothkamm, Kai [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Lab. fuer Strahlentherapie und Experimentelle Radioonkologie; Zips, Daniel (ed.) [Tuebingen Univ. (Germany). Universitaetsklinik fuer Radioonkologie

    2016-05-01

    The proceedings of the 25th symposium on experimental radiotherapy and clinical radiobiology include papers on the following issues: radiotherapy individualization based on imaging; pre-clinic imaging and new experimental methods; methods and models, micromilieu and metabolism, combined therapy; secondary tumors following radiotherapy; radiogenic effects in normal tissue; resistance mechanism of tumors and normal tissue; personalized radio-oncology - which biological data are needed; pre-clinic and personalized radio-oncology; biomarkers - pre-clinic and translational; translational examinations for personalized radio-oncology.

  2. The origins of radiotherapy: Discovery of biological effects of X-rays by Freund in 1897, Kienböck’s crucial experiments in 1900, and still it is the dose

    International Nuclear Information System (INIS)

    The discovery of X-rays by Wilhelm Conrad Röntgen (1845–1923) was triggered by pursuing an anomalous phenomenon: arousal of fluorescence at a distance from tubes in which cathode rays were elicited, a phenomenon which suggested the existence of a new kind of ray other than cathode rays. The discovery of biological effects of these X-rays by Leopold Freund (1868–1943) was triggered by pursuit of the purportedly useless phenomenon of epilation and dermatitis ensuing from X-ray-diagnostic experiments that others had reported. The crucial experiments performed by Robert Kienböck (1871–1953) entailed the proof that X-ray-dose, not electric phenomena, was the active agent of biological effects ensuing when illuminating the skin using Röntgen tubes. For both the discovery of X-rays and the discovery of their biological effectiveness, priority did not matter, but understanding the physical and medico-biological significance of phenomena that others had ignored as a nuisance. Present discussions about the clinical relevance of improving the dose distribution including protons and other charged particles resemble those around 1900 to a certain degree

  3. Advances in radiotherapy

    International Nuclear Information System (INIS)

    Radiation therapy is in the midst of a rebirth largely driven by the use of computers for treatment planning and beam delivery. The first edge of this renaissance was the advent of three-dimensional conformal radiation therapy (3-D CRT). This was enabled by the widespread availability and utilization of three-dimensional imaging such as computed tomography and magnetic resonance scanning, themselves products of the computer revolution. For the first time this allowed radiation oncologists to segment and visualize the tumor in association with it neighboring sensitive soft-tissue structures. Software tools to visualize the beam paths through the body enabled the beam directions and beam shapes to be manually optimized. Simultaneously, improved dose calculations utilizing the CT images of the patient anatomy produced more accurate distributions of dose. The dose was delivered with custom-shaped blocks or recently collimators with multiple leaves that allow complex shaped fields to be delivered without the need for block fabrication. In the last couple of decades new treatment delivery methodologies have emerged. The first has been stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) which is the purview of neurosurgeons (who call it SRS) as well as radiation oncologists (who usually call it SRT). SRS and SRT are premised on multiple beams focusing on one location typically with circular aperture collimators but increasingly with fields shaped by multi-leaved collimators. Often only a single treatment session (the usual for SRS) is used when the treatment volume is small, but for larger lesions several treatment sessions, or fractions, are used (most often for SRT) to allow for normal tissue repair. The new equipment market for SRS and SRT is about 10% of the total for radiation therapy. Intensity-modulated radiation therapy (IMRT) is the latest treatment methodology and its adoption has been extremely rapid, particularly in the United States. IMRT uses

  4. Small animal image-guided radiotherapy: status, considerations and potential for translational impact

    OpenAIRE

    Butterworth, K. T.; Prise, K M; Verhaegen, F

    2014-01-01

    Radiation biology is being transformed by the implementation of small animal image-guided precision radiotherapy into pre-clinical research programmes worldwide. We report on the current status and developments of the small animal radiotherapy field, suggest criteria for the design and execution of effective studies and contend that this powerful emerging technology, used in combination with relevant small animal models, holds much promise for translational impact in radiation oncology.

  5. Heterogeneity correction in the construction of optimized planning in radiotherapy using linear programming

    OpenAIRE

    Rodrigo Sartorelo Salemi Viana; Helenice de Oliveira Florentino; Ernesto Augusto Bueno da Fonseca Lima; Paulo Roberto da Fonseca; Thiago Pedro Donadon Homem

    2011-01-01

    A radiotherapy planning is considered optimal when all the parameters involved, physical or biological, have been investigated and appropriate for each patient. In this type of planning, the major concern is with the tumor irradiation with the minimum possible damage to healthy tissues of the irradiated region, especially the organs at risk. The optimal planning for radiotherapy can be aided by Linear Programming and there is a wide literature addressing this subject. However, most published ...

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

    OpenAIRE

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

    2016-01-01

    Purpose Definitive radiotherapy is often used for chest wall desmoid tumours due to size or anatomical location. The delivery of radiotherapy is challenging due to the large size and constraints of normal surrounding structures. We compared the dosimetry of 3D conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc radiotherapy (VMAT) to evaluate the best treatment option. Methods and materials Ten consecutive patients with inoperable chest wall de...

  7. Radiotherapy in a public health

    International Nuclear Information System (INIS)

    The aim of our publication is to evaluate the state of radiotherapy, its role and place in oncology and in the public health system, in order to plan necessities. The cost and economical effectiveness are objectives of the current evaluation. Radiotherapy is strongly dependant of introducing new technologies and the need of gross capital investments. However, their relative cost is reduced due to their long-term use. Because of the serious delay of Bulgaria from the world standards in radiotherapy, the analysis is based on the data published in the scientific literature. The main tendencies and ideas for development are based on the analysis of The Swedish Council on Technology Assessment in Health Care (SBU) and the ESTRO QUARTS project. We use Swedish model for estimating the expenses, having in mind the conditions in Bulgaria (salary, management, patient cares). The main conclusions are: 1) Radiotherapy is basic curative and palliative method in oncology; 2) Bulgarian radiotherapy is at one of the last places in Europe (therapeutic units are 30 years old average, despite their recommended exploitation of 12-20 years); 3) In contradiction to the world tendencies delay grows during the last 10 years; 4) In countries with low or average GDP radiotherapy should be prioritized, due to its low cost in comparison to the other treatment methods in oncology; 5) The need of radiotherapy will continue to grow, this necessitate not only replacement of the old machines but increasing their number 3 times during the next few years; 6) It is necessary to form a modern radiotherapy centers, equipped with at least two compatible units, based on the currently existing radiotherapy departments. (authors)

  8. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

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

  9. Radiotherapy in supratentorial gliomas. A study of 821 cases

    International Nuclear Information System (INIS)

    Purpose: Analysis of the results of radiotherapy in a large group of cerebral gliomas with identification of prognostic factors and the outcome with respect to different decades of treatment. Patients and Methods: Two decades (1979-1999) of radiotherapy in supratentorial astrocytic and oligodendroglial tumors (n = 821) at the University Hospital Groningen were retrospectively evaluated. Prognostic factors for survival were analyzed. Two decades of radiotherapy treatment were compared with respect to radiotherapy dose and treatment-field design. Results: Glioblastoma multiforme, including gliosarcoma, was the most frequent supratentorial glioma (n = 442) with a poor survival, i.e., median survival time (MST) 7 months, especially in patients > 50 years of age and with poor performance. Patients with good performance were selected for radiotherapy with an optimum dose of 60 Gy local-field irradiation. However, in patients with poor prognosis, no radiotherapy was applied or a shorter treatment scheme was given. Anaplastic astrocytomas (n = 131) were treated in the same way as glioblastoma multiforme. Over time, a decrease in radiation dose (from 60 to 45 Gy) and from whole brain irradiation to local-field treatment was observed, following the literature. In low-grade gliomas, prognostic factors for survival were age, performance, and extent of resection. Gemistocytic astrocytoma (n = 15) had an inferior survival compared to astrocytoma (MST 46 vs. 54 months), but a superior survival compared to anaplastic astrocytoma (MST 10 months). The presence of an oligodendroglial component in a glioma implied a superior survival compared to the astrocytic gliomas. The inherent biology of the glioma is reflected by the study of recurrent tumors with progression to higher grades of malignancy in 32-40% and by the histology of recurrent oligodendroglial tumors. In comparing two decades of radiotherapy in gliomas, no differences in survival were observed despite the technological

  10. Radiotherapy in supratentorial gliomas. A study of 821 cases

    Energy Technology Data Exchange (ETDEWEB)

    Heesters, M. [Dept. of Radiotherapy, Groningen Univ. Hospital (Netherlands); Molenaar, W. [Dept. of Pathology, Groningen Univ. Hospital (Netherlands); Go, G.K. [Dept. of Neurosurgery, Groningen Univ. Hospital (Netherlands)

    2003-09-01

    Purpose: Analysis of the results of radiotherapy in a large group of cerebral gliomas with identification of prognostic factors and the outcome with respect to different decades of treatment. Patients and Methods: Two decades (1979-1999) of radiotherapy in supratentorial astrocytic and oligodendroglial tumors (n = 821) at the University Hospital Groningen were retrospectively evaluated. Prognostic factors for survival were analyzed. Two decades of radiotherapy treatment were compared with respect to radiotherapy dose and treatment-field design. Results: Glioblastoma multiforme, including gliosarcoma, was the most frequent supratentorial glioma (n = 442) with a poor survival, i.e., median survival time (MST) 7 months, especially in patients > 50 years of age and with poor performance. Patients with good performance were selected for radiotherapy with an optimum dose of 60 Gy local-field irradiation. However, in patients with poor prognosis, no radiotherapy was applied or a shorter treatment scheme was given. Anaplastic astrocytomas (n = 131) were treated in the same way as glioblastoma multiforme. Over time, a decrease in radiation dose (from 60 to 45 Gy) and from whole brain irradiation to local-field treatment was observed, following the literature. In low-grade gliomas, prognostic factors for survival were age, performance, and extent of resection. Gemistocytic astrocytoma (n = 15) had an inferior survival compared to astrocytoma (MST 46 vs. 54 months), but a superior survival compared to anaplastic astrocytoma (MST 10 months). The presence of an oligodendroglial component in a glioma implied a superior survival compared to the astrocytic gliomas. The inherent biology of the glioma is reflected by the study of recurrent tumors with progression to higher grades of malignancy in 32-40% and by the histology of recurrent oligodendroglial tumors. In comparing two decades of radiotherapy in gliomas, no differences in survival were observed despite the technological

  11. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  12. Development of targeted radiotherapy systems

    International Nuclear Information System (INIS)

    Conventional or external beam radiotherapy, has been a viable alternative for cancer treatment. Although this technique is effective, its use is limited if the patient has multiple malignant lesions (metastases). An alternative approach is based on the design of radiopharmaceuticals that, to be administered in the patient, are directed specifically toward the target cell producing a selective radiation delivery. This treatment is known as targeted radiotherapy. We have summarized and discussed some results related to our investigations on the development of targeted radiotherapy systems, including aspects of internal dosimetry

  13. Radiotherapy in paediatric oncology

    International Nuclear Information System (INIS)

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

  14. Abstracts of the 28. annual meeting of the Austrian Radiation Oncology, Radiation Biology and Medical Radiation Physics Society (OeGRO 2011); Abstracts der 28. Jahrestagung der Oesterreichischen Gesellschaft fuer Radioonkologie, Radiobiologie und Medizinische Radiophysik (OeGRO 2011)

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2012-06-15

    The second part of the volume includes the abstracts of the 28th annual meeting of the Austrian Radiation Oncology, Radiation Biology and Medical Radiation Physics Society (OeGRO 2011), covering the following topics: extracranial stereotactic radiotherapy; brachytherapy, hyperthermia; radiotherapy side effects; psycho-oncology in radiotherapy; head-neck carcinomas; radiation source implants for carcinoma irradiation; MRI-supported adaptive radiotherapy; CT-guided radiotherapy; mammary carcinomas; prostate carcinomas; magnetic nanoparticles for future medical applications.

  15. [Hepatic tumors and radiotherapy].

    Science.gov (United States)

    Rio, E; Mornex, F; Peiffert, D; Huertas, A

    2016-09-01

    Recent technological developments led to develop the concept of focused liver radiation therapy. We must distinguish primary and secondary tumors as the indications are restricted and must be discussed as an alternative to surgical or medical treatments. For hepatocellular carcinoma 5 to 10cm (or more), a conformational radiation with or without intensity modulation is performed. Stereotactic body radiotherapy (SBRT) is being evaluated and is increasingly proposed as an alternative to radiofrequency ablative treatment for primary or secondary tumors (typically less than 5cm). Tumor (and liver) movements induced by respiratory motions must be taken into account. Strict dosimetric criteria must be met with particular attention to the dose-volume histograms to liver and the hollow organs, including cases of SBRT. PMID:27521035

  16. Radiotherapy for bone metastases

    International Nuclear Information System (INIS)

    Between December 1986 and January 1978, 68 patients with bone metastases were analyzed to evaluate the effect of radiation for the relief of pain. The 68 patients, who had a total of 97 lesions, complained of pain caused by their bone metastasis. The good, fair, and poor responses were found to be 18%, 60%, and 22%, respectively. With reference to the primary neoplasms, the effective response rate was 73% in lung cancer, 100% in breast cancer, 75% in gastric cancer, 100% in hepatic cancer, 100% in bladder cancer, 25% in epipharyngeal cancer, and 70% in the other neoplasms. Depending on the cell types of the lung cancer, the effective response rate was 80% for small cell carcinomas, 72% for adenocarcinomas and 40% for squamous cell carcinomas. Our results suggest that radiotherapy for bone metastases is to be recommended, since the effective response rate was 78% for the relief of pain. (author)

  17. Radiotherapy in pancreatic cancer

    International Nuclear Information System (INIS)

    Purpose and approach: to summarize the current knowledge on the role of radiotherapy in the treatment of pancreatic ductal adenocarcinoma (PDAC). The results of meta-analyses, phase III-studies, and phase II-studies using chemoradiation (CRT) and chemotherapy for resectable and non-resectable PDAC are reviewed. Results and conclusion: the role of CRT is undefined in the adjuvant setting but there may be a role as additive treatment after R1 resection. Locally advanced borderline resectable tumors may shrink down and be subject to potentially curative resections. In locally advanced clearly unresectable cancers the effect of CRT as well as chemotherapy is poorly defined and the sequence of chemotherapy and CRT should be re-evaluated. Patients with PDAC should always be treated within studies to identify optimal treatment results. (orig.)

  18. Tumours following retinoblastoma radiotherapy

    International Nuclear Information System (INIS)

    Radioinduced tumours in young patients irradiated in childhood for retinoblastoma take on a particularly deadly aspect. The onset of this true clinical entity characterized by a long post-irradiation latency period induced by a dose above 6000 rads is a real tragedy. The vast majority of patients then enter into a long martyrdom ending in death. The only cure is surgical, but seldom possible. Treatment is limited to palliative radiotherapy, effective for a while, and chemiotherapy as a last resort but often difficult to prescribe. Prevention alone is the answer. The quality and reliability of the radiotherapeutic treatment depend not only on the personal talent of the radiotherapist but above all on the standard of the equipment. A strong reduction in the doses employed as well as recent technological progress improving the material, its precision and reproducibility appear already to have lowered the frequency curve of these fatal radioinduced tumours

  19. MRI assisted radiotherapy planning

    International Nuclear Information System (INIS)

    To obtain the optimal radiation field, an MR simulation system (MRSS) has been developed. The system consists of an MR unit, a work station and a laser marking system. Phantom study concerned geographic distortion and the total accuracy of MRSS, the former revealed the result lesser than 1 mm within 90 mm-distance between MR slices and Center of magnetic field, the latter showed maximal errors 2 mm in the field size, and 3 mm in the iso-center. This system was applied to 15 patients with intracranial or head and neck lesions and all procedures were smoothly performed. To evaluate the usefulness of MRSS, 6 radiation oncologists compared the difference between MRSS and CT simulation system in setting radiation field. The results were satisfactory especially in cases with lesions the extent of which was unclear on CT images. It was considered that this system could support the radiotherapy planning for intracranial or head and neck lesions. (author)

  20. Image guided multibeam radiotherapy

    International Nuclear Information System (INIS)

    This paper provides an outlook of the status of the first development stages for an updated design of radiotherapy conformal system based on tumor 3D images obtained as an output the last generation imaging machines as PET, CT and MR which offer a very valuable output in cancer diagnosis. Prospective evaluation of current software codes and acquisition of useful experience in surgical planning involves a multidisciplinary process as an initial and unavoidable stage to develop an expert software and user skills which assures the delivery of the radiation dose is done correctly in geometry and value in each voxel as a radiation protection basic condition. The validation of the images obtained has been done by the production of anatomical models of interest regions by rapid prototyping of the 3D segmented images and its evaluation by contrasting with the real regions during surgical procedures. (author)

  1. Image guided multibeam radiotherapy

    International Nuclear Information System (INIS)

    This paper provides an outlook of the status of the first development stages for an updated design of radiotherapy conformal system based on tumor 3D images obtained as an output the last generation imaging machines as PET, CT and MR which offer a very valuable output in cancer diagnosis. Prospective evaluation of current software codes and acquisition of useful experience in surgical planning involves a multidisciplinary process as an initial and unavoidable stage to develop an expert software and user skills which assures the delivery of the radiation dose is done correctly in geometry and value in each voxel as a radiation protection basic condition. The validation of the images obtained has been done by the production of anatomical models of interest regions by rapid proto typing of the 3D segmented images and its evaluation by contrasting with the real regions during surgical procedures. (author)

  2. European Society for Radiation Biology 21. annual meeting

    International Nuclear Information System (INIS)

    The volume contains about 100 abstracts of lectures presented to the conference covering a large variety of topics like: Radiobiology as a base for radiotherapy, radiation carcinogenesis and cellular effects, late and secondary effects of radiotherapy, radioprotection and radiosensitization, heavy ions in radiobiology and space research, microdosimetry and biological dosimetry, radiation effects on the mature and the developing central nervous system, DNA damage and repair and cellular mutations, the imact of radiation on the environment, free radicals in radiation biology

  3. Radiotherapy in prostate cancer. Innovative techniques and current controversies

    Energy Technology Data Exchange (ETDEWEB)

    Geinitz, Hans [Krankenhaus der Barmherzigen Schwestern, Linz (Austria). Dept. of Radiation Oncology; Linz Univ. (Austria). Medical Faculty; Roach, Mack III [California Univ., San Francisco, CA (United States). Dept. of Radiation Oncology; Van As, Nicholas (ed.) [The Institute of Cancer Research, Sutton Surrey (United Kingdom)

    2015-04-01

    Examines in detail the role of innovative radiation techniques in the management of prostate cancer, including IMRT, IGRT, BART, and modern brachytherapy. Explores a range of current controversies in patient treatment. Intended for both radiation oncologists and urologists. Radiation treatment is rapidly evolving owing to the coordinated research of physicists, engineers, computer and imaging specialists, and physicians. Today, the arsenal of ''high-precision'' or ''targeted'' radiotherapy includes multimodal imaging, in vivo dosimetry, Monte Carlo techniques for dose planning, patient immobilization techniques, intensity-modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), biologically adapted radiotherapy (BART), quality assurance methods, novel methods of brachytherapy, and, at the far end of the scale, particle beam radiotherapy using protons and carbon ions. These approaches are like pieces of a puzzle that need to be put together to provide the prostate cancer patient with high-level optimized radiation treatment. This book examines in detail the role of the above-mentioned innovative radiation techniques in the management of prostate cancer. In addition, a variety of current controversies regarding treatment are carefully explored, including whether prophylactic treatment of the pelvic lymphatics is essential, the magnitude of the effect of dose escalation, whether a benefit accrues from hypofractionation, and what evidence exists for the superiority of protons or heavy ions. Radiotherapy in Prostate Cancer: Innovative Techniques and Current Controversies is intended for both radiation oncologists and urologists with an interest in the up-to-date capabilities of modern radiation oncology for the treatment of prostate cancer.

  4. Radiotherapy in the Hodgkin's disease

    International Nuclear Information System (INIS)

    An up-to-date summary of Hodgkin's disease is presented taking into account its natural history, dissemination patterns, history, staging and therapeutic sugestions, with special regard to radiotherapy. (Author)

  5. Radiotherapy: yesterday, today and tomorrow

    International Nuclear Information System (INIS)

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

  6. Contact radiotherapy. Report of technological assessment

    International Nuclear Information System (INIS)

    This report aims at assessing safety, indications, the role in therapeutic strategy, and efficiency of contact radiotherapy. It also aims at answering questions like: is the contact radiotherapy technique validated? What are the indications for contact radiotherapy? What about the efficiency and safety of contact radiotherapy? After a presentation of preliminary notions on radiotherapy (radiation types, dose, and irradiation techniques), the report presents this specific technique of contact radiotherapy: definition, devices, use recommendations, issues of radiation protection, modalities of performance of a contact radiotherapy session, and concerned pathologies. Then, based on a literature survey, this report addresses the various concerned tumours (skin, rectum, brain, breast), indicates some general information about these tumours (epidemiological data, anatomy and classification, therapeutic options, radiotherapy), and proposes an assessment of the efficiency and safety of contact radiotherapy

  7. Future directions for radiotherapy: Gray or Blue perspective?

    International Nuclear Information System (INIS)

    Over the past 20 years radiobiological and clinical rationale for altered radiotherapy were defined. Better understanding of the importance of dose per fraction, ovetrall treatment time, time interval between fractions, and tumor and normal tissue repair mechanisms have contributed to the studies on accelerated (AF) and hyperfractionated (HF) radiotherapy. The results of these studies lead to development of combined AF-HF schedules. Among numerous pilot and randomized studies the only few were recognized as important. Hyperfractionation was found to be advantageous in advanced oropharyngeal cancers, and CHART increased therapeutic gain in advanced laryngeal cancer. Accelerated hyperfractionation (AF-FH) improves local control and/or permits a lower total dose for the same rate of control. Better tumor control has always involved increased severity of acute mucosal reactions. The results of clinical trials which improved effectiveness of radiotherapy are discussed. A variety of physical parameters used in altered fractionation makes difficult the comparison of biological effect of different fractionation regimens based on doses in Grays. A new concept of Biological Units of effectiveness - BLUE, proposed by Withers is presented. It is interesting complex system of biological dosimetry which might supplement the Gray doses. Basic assumption of this concept and practical example are presented. (author)

  8. Indications for Salivary Gland Radiotherapy.

    Science.gov (United States)

    Thomson, David J; Slevin, Nick J; Mendenhall, William M

    2016-01-01

    There is an established role for post-operative radiotherapy in the treatment of benign and malignant salivary gland tumours. For benign disease, the addition of radiotherapy improves local tumour control in cases with incomplete excision, involved surgical margins or multi-focal disease recurrence. After capsule rupture or spillage alone, surveillance should usually be advised. For malignant disease, post-operative radiotherapy is recommended for an advanced tumour stage, high-grade tumour, perineural or lympho-vascular invasion, close or positive resection margins, extra-parotid extension or lymph node involvement. The main benefit is increased loco-regional tumour control, although this may translate into a modest improvement in survival. The possible late side effects of parotid bed irradiation include skin changes, chronic otitis externa, sensorineural hearing loss, osteoradionecrosis and secondary malignancy. Severe complications are rare, but patients should be counselled carefully about the risks. Primary radiotherapy is unlikely to be curative and is reserved to cases in which resection would cause unacceptable functional or cosmetic morbidity or would likely result in subtotal resection (R2) or to patients with distant metastases to gain local tumour control. There are provisional data on the use of charged particle radiotherapy in this setting. Some patients may benefit from synchronous chemotherapy with radiotherapy, but this group is not defined, and data from comparative prospective studies are required before routine clinical use of this treatment. PMID:27093301

  9. Education in physics of radiotherapy

    International Nuclear Information System (INIS)

    Radiotherapy is the clinical application which requires the highest precision in dose delivery because of the very high doses administrated to patients, taking into account that new diagnostic methods and new modalities and treatment machines give greater possibilities of dose escalation. These higher doses may also produce serious side effects if not accurately administered. High qualified personnel is therefore needed for dealing with these new complex modalities, assuring that dose prescribed is correctly administered and providing adequate radiation protection to patients, public and staff. Education in Physics of Radiotherapy aims to provide students with solid theoretical and practical basis in order to be able to work with great responsibility and understanding in a Radiotherapy Department and assure that appropriate radiation protection to patients, public and staff. Since 1964 the National Atomic Energy Commission (CNEA) gives course related to Radiotherapy and since 2002, due to a collaborative project, these courses are given at the Oncology Institute 'Angel H. Roffo' (IOAR) which belongs to the University of Buenos Aires (UBA). The IOAR is well equipped in Radiotherapy and new techniques are continuously introduced. That is why, being a University Institution and having highly specialized staff, it is the ideal hospital for teaching Radiotherapy in Buenos Aires, not only for regular courses but also for implementing workshops, seminars and updating courses as well. Continuous education helps to create and increase awareness of the importance of radiation protection in patients as well as in public and staff. (author)

  10. Radiotherapy-induced mandibular bone complications.

    Science.gov (United States)

    Jereczek-Fossa, Barbara A; Orecchia, Roberto

    2002-02-01

    The mandible is among the bones most frequently affected by irradiation. The most severe post-radiation injury of the mandible is osteoradionecrosis (ORN). Conflicting data have been reported on the incidence of this complication, its aetiology and management. The incidence of mandibular ORN in head and neck cancer patients managed with radical or postoperative irradiation, has varied widely in the literature from 0.4% to 56%. The interpretation of data derived from particular series are difficult due to the different scoring methods and classification systems used for the evaluation of post-radiation bone damage. Although ORN occurs typically in the first three years after radiotherapy, patients probably remain at indefinite risk. The diagnosis of ORN is principally based on the clinical picture of chronically exposed bone. Radiological symptoms include decreased bone density with fractures, cortical destruction and loss of spongiosa trabeculation. Numerous factors that may be associated with the risk of ORN include treatment-related variables (for example, total radiotherapy dose, biologically effective dose, photon energy, brachytherapy dose rate, combination of external beam irradiation and interstitial brachytherapy, field size, fraction size, volume of the mandible irradiated with a high dose), patient-related variables (like deep parodontitis, pre-irradiation bone surgery, bad oral hygiene, alcohol and tobacco abuse, bone inflammation, dental extraction after radiotherapy) and tumour-related factors (tumour size or stage, proximity of the tumour to bone, anatomic tumour site). Primary management of post-radiation bone lesions include conservative modalities such as saline irrigations, antibiotics during infectious episodes, topically applied antiseptics, gentle sequestrectomy and removal of visibly loosened bone elements as well as treatment with hyperbaric oxygen (HBO). Surgery is reserved for persistent ORN and includes radical resection of the lesion

  11. Gene therapy and radiotherapy in malignant tumor

    International Nuclear Information System (INIS)

    Tumor treatment is one of the most important fields in medical research. Nowadays, a novel method which is combined gene therapy with radiotherapy plays an important role in the field of cancer research, and mainly includes immune gene therapy combined with radiotherapy, suicide gene therapy or tumor suppressor gene therapy combined with radiotherapy, antiangiogenesis gene therapy combined with radiotherapy and protective gene therapy combined with radiotherapy based on the technical features. This review summarized the current status of combined therapies of gene therapy and radiotherapy and possible mechanism. (authors)

  12. Radioprotectors in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nair, C.K.K. [Bhabha Atomic Research Centre, Mumbai (India); Parida, D.K.; Nomura, Taisei

    2001-03-01

    This review article focuses on clinically relevant radioprotectors and their mechanisms of radioprotection. Radiotherapy is the most common modality of human cancer therapy. Obtaining optimal results requires a judicious balance between the total dose of radiotherapy delivered and the threshold limit of critical surrounding normal tissues, and the normal tissues need to be protected against radiation injury to obtain better tumor control by using a higher dose. For this reason, radiation-protective agents play an important role in clinical radiotherapy. Radiation-protective agents can be classified into three groups: radioprotectors, adaptogens, and absorbents. The first group generally consists of sulfhydryl compounds and other antioxidants. They include several myelo-, entero-, and cerebro-protectors. Adaptogens act as promotors of radioresistance. They are natural protectors that offer chemical protection against low levels of ionizing radiation. Absorbents protect organs from internal radiation and chemicals. They include drugs that prevent incorporation of radioiodine by the thyroid gland and absorption of radionuclides. This article thoroughly describes the properties, mechanisms of action, and perspectives on clinical application of the following categories of radioprotectors: sulfhydryl compounds (e.g., cysteine, cysteamine, glutathione, AET, WR 2127, and other WR-compounds), antioxidants (e.g., tempace, Hoechst 33342, vitamin A, E, and C, TMG, melatonin), angiotensin-converting enzyme (ACE) inhibitors (e.g., captopril, elanopril, penicillamine, pentoxifylline, L-158, 809), cytoprotective agents (mesna, dexrazoxane, and amifostin), metalloelements (e.g., manganese chloride, cadmium salts, bismuth subnitrate), immunomodulators (gamma-interferon, polysaccharides AM5, AM218, heat-killed lactobacillus cells, broncho-vaxom, trehalose dicorynomycolate, and AS101), lipopolysaccharides and prostaglandins, plant extracts and compounds isolated from plants (curcmin

  13. Review of potential improvements using MRI in the radiotherapy workflow

    International Nuclear Information System (INIS)

    The goal of modern radiotherapy is to deliver a lethal amount of dose to tissue volumes that contain a significant amount of tumour cells while sparing surrounding unaffected or healthy tissue. Online image guided radiotherapy with stereotactic ultrasound, fiducial-based planar X-ray imaging or helical/conebeam CT has dramatically improved the precision of radiotherapy, with moving targets still posing some methodical problems regarding positioning. Therefore, requirements for precise target delineation and identification of functional body structures to be spared by high doses become more evident. The identification of areas of relatively radioresistant cells or areas of high tumor cell density is currently under development. This review outlines the state of the art of MRI integration into treatment planning and its importance in follow up and the quantification of biological effects. Finally the current state of the art of online imaging for patient positioning will be outlined and indications will be given what the potential of integrated radiotherapy/online MRI systems is.

  14. Review of potential improvements using MRI in the radiotherapy workflow

    Energy Technology Data Exchange (ETDEWEB)

    Torresin, Alberto; Brambilla, Maria Grazia; Monti, Angelo F.; Moscato, Alessio [Azienda Ospedale Niguarda Ca' Granda, Dept. of Medical Physics, Milano (Italy); Brockmann, Marc A. [University Hospital of the RWTH Aachen (Germany). Dept. of Diagnostic and Interventional Neuroradiology; University Medical Center Mannheim (Germany). Dept. of Neuroradiology; Schad, Lothar [University Medical Center Mannheim (Germany). Computer Assisted Clinical Medicine; Attenberger, Ulrike I. [University Medical Center Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Lohr, Frank [University Medical Center Mannheim (Germany). Dept. of Radiation Oncology

    2015-07-01

    The goal of modern radiotherapy is to deliver a lethal amount of dose to tissue volumes that contain a significant amount of tumour cells while sparing surrounding unaffected or healthy tissue. Online image guided radiotherapy with stereotactic ultrasound, fiducial-based planar X-ray imaging or helical/conebeam CT has dramatically improved the precision of radiotherapy, with moving targets still posing some methodical problems regarding positioning. Therefore, requirements for precise target delineation and identification of functional body structures to be spared by high doses become more evident. The identification of areas of relatively radioresistant cells or areas of high tumor cell density is currently under development. This review outlines the state of the art of MRI integration into treatment planning and its importance in follow up and the quantification of biological effects. Finally the current state of the art of online imaging for patient positioning will be outlined and indications will be given what the potential of integrated radiotherapy/online MRI systems is.

  15. Moving toward multi-dimensional radiotherapy and the role of radiobiology

    International Nuclear Information System (INIS)

    Recent radiotherapy for cancer treatment enable the high-precision irradiation to the target under the computed image guidance. Developments of such radiotherapy has played large role in the improved strategy of cancer treatments. In addition, the molecular mechanistic studies related to proliferations of cancer cell contribute the multidisciplinary fields of clinical radiotherapies. Therefore, the combination of the image guidance and molecular targeting of cancer cells make it possible for individualized cancer treatment. Especially, the use of particle beam or boron neutron capture therapy (BNCT) has been spotlighted, and installations of such devices are planned widely. As the progress and collaborations of radiation biology and engineering physics, establishment of a new style of radiotherapy becomes available in post-genome era. In 2010s, the hi-tech machines controlling the spaciotemporal radiotherapy become in practice. Although, there still remains to be improved, e.g., more precise prediction of radiosensitivity or growth of individual tumors, and adverse outcomes after treatments, multi-dimensional optimizations of the individualized irradiations based on the molecular radiation biologies and medical physics are important for further development of radiotherapy. (author)

  16. Experimental radiotherapy and clinical radiobiology. Vol. 18. Proceedings; Experimentelle Strahlentherapie und Klinische Strahlenbiologie. Bd. 18. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Michael; Dahm-Daphi, Jochen; Dikomey, Ekkehard; Petersen, Cordula; Rodemann, H. Peter; Zips, Daniel (eds.)

    2009-07-15

    The proceedings on experimental radiotherapy and clinical radiobiology contain two review articles (prediction of normal tissue reactions after radiotherapy, ?H2AX foci as a marker for DNA double-strand breaks) and 34 contributions to the following topics: Hypoxia and molecular mechanisms of radiation resistance; biological imaging of the tumor micromilieu; DNA repair, genomic instability and carcerogenesis; molecular factors of radiation resistance; actual controversial discussion on possible irradiation caused metastasis risk enhancement; EGFR inhibition and irradiation; biology of experimental radiation/ normal tissue toxicity.

  17. Voice following radiotherapy

    International Nuclear Information System (INIS)

    This study was undertaken to provide information on the voice of patients following radiotherapy for glottic cancer. Part I presents findings from questionnaires returned by 227 of 235 patients successfully irradiated for glottic cancer from 1960 through 1971. Part II presents preliminary findings on the speaking fundamental frequencies of 22 irradiated patients. Normal to near-normal voice was reported by 83 percent of the 227 patients; however, 80 percent did indicate persisting vocal difficulties such as fatiguing of voice with much usage, inability to sing, reduced loudness, hoarse voice quality and inability to shout. Amount of talking during treatments appeared to affect length of time for voice to recover following treatments in those cases where it took from nine to 26 weeks; also, with increasing years since treatment, patients rated their voices more favorably. Smoking habits following treatments improved significantly with only 27 percent smoking heavily as compared with 65 percent prior to radiation therapy. No correlation was found between smoking (during or after treatments) and vocal ratings or between smoking and length of time for voice to recover. There was no relationship found between reported vocal ratings and stage of the disease

  18. Margins in radiotherapy

    International Nuclear Information System (INIS)

    As part of the treatment prescription procedure, one has to prescribe in anatomical terms any GTV (Gross Tumor Volume) according to the general TNM-rules as well as any other tissues that are to be treated for presumed subclinical diseases. These prescriptions of one or several Clinical Target Volumes (CTVs) are based on general oncological principles, and are not related to the treatment modality. If external beam radiotherapy is being used, one has to consider special problems related to different geometric inaccuracies and uncertainties, which can be both intrafractional and interfractional. Such inaccuracies and uncertainties are due to either the position, shape and size of the patient/tissues in relation to a fix point, or to variations in beam geometry. The two different types of variations may or may not co-variate. A margin or margins for these uncertainties has to be included in the dose planning procedure, which then will evaluate a static situation, representing the CTV(s) plus geometric ''safety'' margin(s) (Planning Target Volume, PTV) and in fact not the true clinical situation. The dose distribution arrived at for this static representation will however have to be considered as representative for the CTV. This presents of course a dilemma, but one has to accept a reasonable compromise. There is no general rule on the size of the different geometric uncertainties or how they should be added up. Individual evaluations are needed. (author)

  19. Automatization in radiotherapy

    International Nuclear Information System (INIS)

    Data-processing in external radiotherapy has to be adapted to each local situation, taking into account the patients to be treated, the irradiation equipment, the data-processing centers available locally, regionally, and nationally, and the rentability of the data-processing system required. It should be recalled that most dosimetric methods used today can be treated manually, and the question of rentability has to be kept in mind when deciding to buy a data-processing system. The radiotherapist should, therefore, prepare a list of costs for each situation, and verify the validity of each programme proposed by the supplier. It is difficult to make a definite choice between the presently available systems. The radiotherapist has to choose in relation to his activity, his availability and the systems available to him. It can sometimes be more advantageous to have a terminal linked to a large computer, rather than to readapt a series of programmes for a data-processing system available locally: many such solutions, though original, cannot be 'exported'. It should be recalled that a large number of dosimetries can be obtained manually, and on the rare occasions when the aid of a computer is essential, the assistance of better equipped neighbouring centers can be obtained. The decision as to whether a data-processing system needs to be acquired has to take all these imperatives into account

  20. Contribution of customised dosimetry for small animal to the treatments of cancers by metabolic radiotherapy

    International Nuclear Information System (INIS)

    This research thesis first reports a bibliographical study which addressed the use of ionizing radiations in cancer therapy (evolution from ionizing radiation to metabolic radiotherapy, biological and physical parameters, and absorbed dose in metabolic radiotherapy) and the role imagery has in customised dosimetry (absorbed dose calculation methods, determination of cumulative activity, dosimetric models for S factor calculation). Then, the author presents a software which has been specifically developed for the creation of dosimetric models, and reports its validation. He reports the comparison between different dosimetric models in the case of mice. He highlights two applications of the developed tool: radio-immunotherapy and metabolic radiotherapy. He finally proposes a general discussion on the impact of small animal dosimetry on metabolic radiotherapy

  1. Special procedures and techniques in radiotherapy

    International Nuclear Information System (INIS)

    In addition to the routine conventional radiotherapy techniques used in standard radiotherapy departments and clinics, several specialized techniques are known and used for special procedures, be it in dose delivery or target localization. These techniques deal with specific problems that usually require equipment modifications, special quality assurance procedures and heavy involvement and support from clinical physicists. Owing to their increased complexity, these specialized techniques are usually available only in larger, regional centres. The radiotherapy techniques that currently fall into the specialized category are listed below; the first six are special dose delivery techniques, the last three are special target localization techniques: Stereotactic irradiation; Total body irradiation (TBI) with photon beams; Total skin electron irradiation (TSEI); Intraoperative radiotherapy (IORT); Endorectal irradiation; Conformal radiotherapy and intensity modulated radiotherapy (IMRT); Image guided radiotherapy (IGRT); Respiratory gated radiotherapy; Positron emission tomography (PET)/computed tomography (CT) fused images

  2. Protection of patient In radiotherapy

    International Nuclear Information System (INIS)

    The purpose of this project is to clarify some aspects about protection of patient in radiotherapy. Therefore, some basic information about how the use of ionizing radiation in medicine has brought tremendous health benefits to the population globally, the requirement of radiation protection (Justification of practices, Dose limitation and Optimization of protection), and the deterministic and stochastic effects of radiation are presented. The aim of radiotherapy is to use ionizing radiation to cure diseases or make the symptoms of a disease less severe. Also presented are layout of a radiotherapy facility (controlled areas, supervised areas, mazes, door and interlocks, patient observation and communication, and warning sign and lights), radionuclides commonly used for radiation therapy and their main emissions, equipment and devices used in radiotherapy, aspect of protection of patient in radiotherapy such as: leakage test, source on/off, emergency buttons, radiation oncology team, treatment planning, room monitoring, equipment or for protection and Cobalt-60 unit stuck source. The advantages of brachytherapy, leakage from the treatment head and radiation incidents resulting from incorrect dose calibration are discussed. The importance of minimization dose exposure, by considering the basic principles of: time, distance and shielding are also stated. These principles prevent deterministic effects and limit stochastic effects of radiation. (author)

  3. Technological advances in radiotherapy for esophageal cancer

    Institute of Scientific and Technical Information of China (English)

    Milan; Vosmik; Jiri; Petera; Igor; Sirak; Miroslav; Hodek; Petr; Paluska; Jiri; Dolezal; Marcela; Kopacova

    2010-01-01

    Radiotherapy with concurrent chemotherapy and surgery represent the main treatment modalities in esophageal cancer.The goal of modern radiotherapy approaches,based on recent technological advances,is to minimize post-treatment complications by improving the gross tumor volume definition (positron emission tomography-based planning),reducing interfraction motion (image-guided radiotherapy) and intrafraction motion (respiratory-gated radiotherapy),and by better dose delivery to the precisely defined planning ...

  4. Computerised tomography in radiotherapy planning

    International Nuclear Information System (INIS)

    This study evaluates the effectiveness of computed tomography as an adjunct to radiotherapy planning. Until recently, acquisition of accurate data concerning tumour anatomy lagged behind other developments in radiotherapy. With the advent of computer-tomography (CT), these data can be displayed and transmitted to a treatment planning computer. It is concluded that the greatest inaccuracies in the radiation treatment of patients are to be found in both the inadequate delineation of the target volume within the patient and changes in body outline relative to the target volume over the length of the irradiated volume. The technique was useful in various subgroups (pelvic, intra-thoracic and chest-wall tumours) and for those patients being treated palliatively. With an estimated improvement in cure rate of 4.5% and cost-effective factors of between 3.3 and 5, CT-assisted radiotherapy planning appears to be a worthwhile procedure. (orig.)

  5. Hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Combined hyperthermia (HT 45 min once or twice per week) and low dose radiotherapy (LDRT 30-34.5 Gy in 2-3 weeks) have been given to 182 locally recurrent or metastatic superficial tumours in 133 patients. Tumour response was analysed in 137 tumours in 100 patients. The overall complete response (CR) was 50% with a median duration (DCR) of 13±3 months. When mammary carcinoma, representing 62% of the treated tumours, were analysed, CR was 62% with a DCR of 14±4 months. In a comparative, non-randomized study, on 34 matched tumour pairs in 24 patients, treatment was given with LDRT+HT to the larger and the same LDRT to the smaller tumour, the patients acting as their own control. A significant difference in CR was obtained in favour of the combined treatment (p=0.0013 all diagnosis and p=0.0027 mammary carcinoma). There was no significant difference in DCR between the two modalities. No significant difference in CR was seen when tumours were randomely treated with HT once (CR 56%) or twice (CR 69%) per week combined with the same LDRT. Predictive factors for CR, multivariately analysed (15 parameters), in mammary carcinoma recurring in earlier irradiated regions, were; the present LDRT absorbed dose (p=0.02) and the average minimum temperature in the best HT session (p=0.03). Significant skin toxicity was seen in 28% of all the 182 heated regions. Prognostic factors for skin damage, multivariately analysed, were; the extension of the heated region (p=0.007) and the highest average maximum temperature in any of the HT sessions (p=0.04). Pain was in some way correlated to severe toxicity but was not considered to be an optimal monitor for HT as many patients with severe and moderate pain were without any serious skin reactions, while slight or no pain sometimes were associated with severe reactions. 401 refs

  6. Mucosal regeneration during radiotherapy

    International Nuclear Information System (INIS)

    Background and purpose: Regeneration of the aerodigestive mucosa is known to occur during conventionally fractionated radiotherapy. The circumstances surrounding its time of onset and magnitude are not well understood, however. Material and methods: Mucosal reactions were observed in 100 patients undergoing conventionally fractionated treatment at 2 Gy/day over 7 weeks and 88 receiving accelerated treatment at 1.8 Gy twice daily over 3(1(2)) weeks on the Trans Tasman Radiation Oncology Group head and neck cancer trials. Similar observations in 61 patients treated palliatively at dose rates between 0.8 and 240 Gy/h using ten 3.0-4.2 Gy fractions over 2 weeks are compared. Results: Several findings emerged from these studies: 1. Reactions evolved more quickly at oropharyngeal sites than in the hypopharynx. 2. Reactions at both sites evolved more rapidly at greater rates of dose accumulation. 3. The timing of reactions suggested the presence of a strong regenerative mucosal response that started before the manifestation of 'patchy' (grade II) mucosal reactions. 4. The regenerative response was strong enough to 'make good' damage accumulated at a rate of 2 Gy/day in over a third of cases. 5. The linear quadratic model without time correction failed to provide an adequate prediction of the frequency or intensity of mucosal reactions produced by any of the regimes. A simple model of the regenerative response is presented. Conclusions: This study suggests that the timing and magnitude of the regenerative response vary between sites and individuals but are linked to the amount of epithelial cellular depletion occurring during treatment

  7. How PET is changing the management of cancer with radiotherapy

    International Nuclear Information System (INIS)

    Information from PET scanning is transforming the management of many malignancies and the impact of PET is likely to increase further as new indications are recognised. PET is of particular value in patients treated with radiotherapy (RT) with curative intent. These patients rarely undergo invasive surgical staging and therefore imaging is crucial in determining the extent of disease before treatment. More accurate staging with PET means that futile aggressive RT or chcmoRT can be avoided in patients with incurable extensive disease. FDG-PET is of proven value in the staging of common metabolically-active malignancies treated with radiotherapy. These include lung cancer, head and neck cancer, lymphomas and oesophageal carcinoma. It has been shown that PET can improve the selection of patients for radical surgery or radiotherapy in lung cancer and that PET-based staging more accurately predicts survival than conventional staging. For those patients that remain eligible for definitive RT after PET. treatment can be more accurately targeted at the tumour and involved regional nodes. The value of PET for treatment planning is enhanced significantly when PET and CT scans are acquired on a combined PET/CT scanner. Fused PET-CT images can be imported into the radiotherapy planning computer and used to accurately target tumour with the best beam arrangement. After treatment, response may be hard to assess with structural imaging. PET-rcsponse to chemotherapy or radiotherapy in non-small cell lung cancer (NSCLC) predicts survival in NSCLC more accurately than CT response. However, PET has much more potential than imaging with FDG alone can realise. Markers such as FLT can be used to image proliferation in tumours, misonidazole or FAZA can be used to image hypoxia and labeled metabolites of anti-cancer drugs such as 5-FU can be used to study pharmacokinetics. New combinations of radiation and drugs may emerge that can be selected based on biological characteristics of

  8. Who risk profile in radiotherapy

    International Nuclear Information System (INIS)

    The different steps of a treatment in radiotherapy are: patient evaluation, decision to treat, prescription of the treatment protocol, positioning and immobilization, simulation, imaging and volume determination, planning and implementation of materials and software, transfer of treatment data, patient positioning, treatment realisation, treatment checking and follow-up. It exist processes of safety for any step of a radiotherapy realisation: patient identification, accreditation of equipment and processes, evaluation of the personnel competencies, quality assurance of equipment and management of the processes quality, redundancy during the data transfer, control of processes, errors reports and quality improvement, external controls, appropriateness of the workforce. (N.C.)

  9. Radiotherapy for recurrent breast cancer

    International Nuclear Information System (INIS)

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

  10. Combined chemotherapy and radiotherapy: Cyclophosphamide

    International Nuclear Information System (INIS)

    Compared to the other chemotherapeutic preparations discussed today, cyclophosphamide in combination with radiotherapy is a relatively unproblematic substance. Despite the great number of experimental and clinical data, the evaluation does not prove an advantage of the combined therapy with cyclophosphamide and irradiation as against radiotherapy alone in local tumor treatment. This should give occasion to further experimental investigations in adequate models. On the other hand, the practice of combined treatment with irradiation and preparations containing cyclophosphamide should be reconsidered for those cases where local control of a tumor is the principal therapeutic aim. (orig.)

  11. Multidimensional radiotherapy for squamous cell cancer of the head and neck: new concept at the edge of clinical practice

    International Nuclear Information System (INIS)

    Recent developments in cancer imaging, computerized treatment planning and therapeutic procedures resulted in a widespread shift towards conformal radiotherapy, in which the isodose distribution matches spatial dimensions of the tumor and dose-limiting structures. Conformal distribution of the physical dose does not, however, entail the conformality of treatment with respect to the biology of the tumor. Further progress in radiotherapy will be possible due to enhanced knowledge of key relationships between the expression of molecular markers and the clinical effect of combined treatment. Such perspective provides the basis for multidimensional radiotherapy, which accounts not only for spatial distribution of the physical radiation dose, but also for dose-time-fractionation, selection of systemic therapy and sequence of treatment, thus conforming to the individual biological characteristics of the tumor. The present report demonstrates the practical applications of multidimensional radiotherapy in the combined treatment for head and neck cancer, with reference to the studies performed in Gliwice, and to data from literature. (authors)

  12. Non-targeted effects of ionising radiation and radiotherapy.

    Science.gov (United States)

    Sjostedt, Svetlana; Bezak, Eva

    2010-09-01

    Modern radiobiology is undergoing rapid change due to new discoveries contradicting the target concept which is currently used to predict dose-response relationships. Thus relatively recently discovered radiation-induced bystander effects (RIBEs), that include additional death, mutation and radio-adaptation in non-irradiated cells, change our understanding of the target concept and broadens its boundaries. This can be significant from a radioprotection point of view and also has the potential to reassess radiation damage models currently used in radiotherapy. This article reviews briefly the general concepts of RIBEs such as the proposed underlying mechanisms of signal induction and propagation, experimental approaches and biological end points used to investigate these phenomena. It also summarises several mathematical models currently proposed in an attempt to quantify RIBE. The main emphasis of this article is to review and highlight the potential impact of the bystander phenomena in radiotherapy. PMID:20857259

  13. Non-Targeted effects of ionising radiation and radiotherapy

    International Nuclear Information System (INIS)

    Full text: Modern radiobiology is undergoing rapid change due to new discoveries contradicting the target concept which is currently used to predict dose-response relationships. Thus relatively recently discovered radiation induced bystander effects (RlBEs), that include additional death, mutation and radio-adaptation in non-irradiated cells, change our understanding of the target concept and broadens its boundaries. This can be significant from a radioprotection point of view and also has the potential to reassess radiation damage models currently used in radiotherapy. This article reviews briefly the general concepts of RlBEs such as the proposed underlying mechanisms of signal induction and propagation, experimental approaches and biological end points used to investigate these phenomena. It also summ rises several mathematical models currently proposed in an attempt to quantify RlBE. The main emphasis of this al1icle is to review and highlight the potential impact of the bystander phenomena in radiotherapy.

  14. Radiological concepts in radiotherapy

    International Nuclear Information System (INIS)

    The atomic explosions in Hiroshima and Nagasaki made the name radiation itself become a nightmare. Notwithstanding this, radiation continued to serve the mankind specially in diagnosis of several human diseases and in the treatment of intractable malignancies. With their latest research tools biologists have now shown a significant shift in the earlier paradigm; even the concept that radiation initiates cancer appears to be no longer tenable. On the contrary, selective radiation doses inhibit growth of cancer cells and radiation in combination with many chemotherapeutic drugs, radiosensitizing chemicals and/or hyperthermia, is emerging as a new modality for cancer treatment which offers high therapeutic advantages. In addition, the deleterious effects of radiation can now be strategically counter poised by the use of many drugs and chemicals. This has been possible by the newer insights gained in the mechanism of biological effects of radiation. The fate of radiation-induced free radicals which are the prime cause of biological consequences following radiation exposure can now be suitably modified by drugs and chemicals. Of late, controversies have also arisen on the beneficial effects of very low dose of radiation and biological dosimetry has gained considerable importance in the assessment of potential risk under such circumstances. All these and related topics are incorporated in the book. Papers relevant to INIS are indexed separately

  15. Introduction to radiation biology

    International Nuclear Information System (INIS)

    This book is arranged in a logical sequence, starting from radiation physics and radiation chemistry, followed by molecular, subcellular and cellular effects and going on to the level of organism. Topics covered include applied radiobiology like modifiers of radiosensitivity, predictive assay, health physics, human genetics and radiopharmaceuticals. The topics covered are : 1. Radiation Physics, 2. Detection and Measurement of Radiation, 3. Radiation Chemistry, 4. DNA Damage and Repair, 5. Chromosomal Aberrations and Gene Mutations, 6. Cellular Radiobiology 7. Acute Radiation Effects, 8. Delayed Effects of Radiation, 9. Biological Basis of Radiotherapy, 10. Chemical Modifiers of Radiosensitivity, 11. Hyperthermia, 12. High LET Radiations in Cancer, Therapy, 13. Predictive Assays, 14. Radiation Effects on Embryos, 15. Human Radiation Genetics, 16. Radiolabelled Compounds in Biology and Medicine and 17. Radiological Health

  16. Construction of a remote radiotherapy planning system

    International Nuclear Information System (INIS)

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

  17. Integrative radiation systems biology.

    Science.gov (United States)

    Unger, Kristian

    2014-01-01

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer" of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology. PMID:24411063

  18. Integrative radiation systems biology

    International Nuclear Information System (INIS)

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group “Personalized Radiotherapy in Head and Neck Cancer” of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology

  19. TOPICAL REVIEW: Anatomical imaging for radiotherapy

    Science.gov (United States)

    Evans, Philip M.

    2008-06-01

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  20. Porphyria and radiotherapy: yet a constellation of risk?; Porphyrie und Radiotherapie: doch eine Risikokonstellation?

    Energy Technology Data Exchange (ETDEWEB)

    Rhomberg, W. [Abt. fuer Radioonkologie, Landeskrankenhaus, Feldkirch (Austria); Offner, F.A. [Abt. fuer Pathologie, Landeskrankenhaus, Feldkirch (Austria)

    2005-06-01

    Background: little is known concerning the relation of porphyrias to radiation treatment for cancer. The recent literature does not report negative outcomes at least in single cases of breast cancer, bladder cancer or in a patient with lymphoma. Theoretically, there is a risk for radiation treatment in cases of porphyrias. Case report: two patients with porphyria are described who underwent radiotherapy for glioblastoma multiforme. Case histories, radiation treatment data and the proof of porphyria are given in detail. The patients received a concomitant radiochemotherapy with infusions of ACNU [1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-(2-chloroethyl)-3-nitrosourea] every 6 weeks. The total radiation doses at the ICRU point were 60 and 38 Gy, respectively, given in single daily fractions of 2 Gy. Results: both patients responded well as far as objective tumor regression is concerned but died early after 7 and 1.5 months following diagnosis. The first patient experienced a large brain necrosis and deterioration of her porphyria. The second patient died of cardiopulmonary insufficiency still during radiotherapy with persistent or even increased signs of porphyria. The tumor showed extensive necrosis already after 38 Gy. Conclusion: in view of annotations in the literature and this case report, caution is advised as for irradiation of brain or nervous tissues in case of porphyrias. Molecular biology data seems to support this warning to some extent. (orig.)

  1. Radiotherapy - past present and future

    International Nuclear Information System (INIS)

    The beginnings of therapeutic applications of x-rays are far less known and surrounded by acrimonious controversy. The past, present and future of radiotherapy are briefly reviewed. The major challenges for hospital physicists is in educating staff members and monitoring the ever broadening use of ionising radiation

  2. Radiotherapy of bile duct carcinoma

    International Nuclear Information System (INIS)

    Twenty-six patients with cholangiocarcinoma and nineteen patients with carcinoma of the gallbladder treated with external radiotherapy were analyzed. Of the twenty-six patients, eighteen had cancer of the hepatic hilus (Klatskin), four intrahepatic and the remaining four extrahepatic cholangiocarcinoma. All but two of the patients had advanced disease. Thirty-three patients received primary irradiation for unresectable tumors, ten patients adjuvant irradiation after non-curative gross tumor resection, and two patients preoperative radiotherapy. Patients with cholangiocarcinoma who underwent radiotherapy with relatively small radiation field tolerated the treatment well, but there was no significant difference in survival according to field size or radiation doses (TDF). On the other hand, patients with carcinoma of gallbladder were treated with larger field size and lower dose. In the patients without gross tumor resection, those receiving radiation doses≥90 TDF had significantly longer survival than 2) had longer survival (p=0.07). The patients with gross tumor resection had significantly longer survival than that without resection in both cholangiocarcinoma and carcinoma of gallbladder. Postmortem examination revealed tumor recurrence even in the patients with gross tumor resection, but widespread distant metastases were present simultaneously. Cholangitis and liver abscess were special and lethal conditions related to these carcinomas, and intensive therapy must be developed for these conditions. External radiotherapy may be effective in the treatment of bile duct carcinoma in terms of palliation and survival. (author)

  3. Radiotherapy T1 glottic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zablow, A.I.; Erba, P.S.; Sanfillippo, L.J.

    1989-11-01

    From 1970 to 1985, curative radiotherapy was administered to 63 patients with stage I carcinoma of the true vocal cords. Precision radiotherapeutic technique yields cure rates comparable to surgical results. Good voice quality was preserved in a high percentage of patients.

  4. Thalassaemic osteoarthropathy treated with radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Davies, A.N. (King' s Coll. Hospital, London (United Kingdom))

    1993-11-01

    Patients with beta thalassaemia may develop a specific osteoarthropathy involving the feet. A number of different treatments for this condition have been tried, including rest, analgesia and hypertransfusion. We report a case of a patient with thalassaemic osteoarthropathy who responded to radiotherapy after failing conventional treatment. (author).

  5. Computerised tomography in radiotherapy planning

    NARCIS (Netherlands)

    P.C. Badcock (Peter)

    1983-01-01

    textabstractSuccessful radiotherapy practice depends on the irradiation of tumours such that their destruction follows without unacceptable damage of the surrounding normal tissues. Until recently the accurate acquisition of data concerning the tumour anatomy lagged behind other developments in radi

  6. Palliative radiotherapy in developing countries

    International Nuclear Information System (INIS)

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

  7. Radiotherapy treatments using Tsallis entropy statistical approach

    Science.gov (United States)

    D, Rodríguez-Pérez; O, Sotolongo-Grau; O, Sotolongo-Costa; C, Antoranz J.

    2014-03-01

    Several radiobiological models mimic the biologic effect of one single radiation dose on a living tissue. However, the actual fractionated radiotherapy requires accounting for a new magnitude, i.e., time. Here, we explore the biological consequences posed by the mathematical prolongation of a previous single radiation model to fractionated treatment. The survival fraction is obtained, together with the equivalent physical dose, in terms of a time dependent factor (similar to a repair coefficient) describing the tissue trend to recovering its radioresistance. The model describes how dose fractions add up to obtain the equivalent dose and how the repair coefficient poses a limit to reach an equivalent dose equal to the critical one that would completely annihilate the tumor. On the other hand, the surrounding healthy tissue is a limiting factor to treatment planning. This tissue has its own repair coefficient and thus should limit the equivalent dose of a treatment. Depending on the repair coefficient and the critical dose of each tissue, unexpected results (failure to fully remove the tumor) can be obtained. To illustrate these results and predictions, some realistic example calculations will be performed using parameter values within actual clinical ranges. In conclusion, the model warns about treatment limitations and proposes ways to overcome them.

  8. Biological aspects of radiation in nuclear medicine

    International Nuclear Information System (INIS)

    Radiotherapy with unsealed radionuclides differs from external radiotherapy with regard to the radiation quality and energy range, the regional dose uniformity and the time course of irradiation regimen. External radiotherapy is planned precisely and can be applied to a target volume independently from blood flow during a course of irradiation fractions. In contrary, administered radiopharmaceuticals distribute according to their pharmacokinetic properties and generate a continuous irradiation corresponding to the effective halflife. The resulting dose rates are approximately 1 Gy/min and 1 Gy/h, respectively. The bio-kinetics of radiopharmaceuticals involves cellular accumulation and retention with highly variable affinity to specific organs that can be modulated as well. A remarkable dose gradient is found at the edge of volumes with enhanced uptake. The biological effect of an irradiation with decreasing intensity can be compared with the radiation effect caused by conventional fractionation with 2 Gy a day in external beam therapy by means of the linear-quadratic model. However, the experimental validation of this translation is still under investigation. Radionuclide therapy is usually performed in several cycles some month apart. This procedure fails to meet external radiotherapy. The vision of a combined external-internal radiotherapy requires efforts for a common dosimetry approach both in vitro and in vivo with a physical and biological verification of the results. (orig.)

  9. Radiotherapy of corpus carcinoma

    International Nuclear Information System (INIS)

    96 women with primary carcinoma corporis uteri and 79 women after surgery were treated between 1965 - 1970 with different radiotherapeutic methods, in some cases in combination with cytostatics and gestagens. In the group of primary radiation best results were obtained with combination of intracavitary brachytherapy and external radiation (55% 5-years-survival), and in the postoperative group with external radiation alone (67% 5-years-survival). Late complications with 17% fibrosis in the parametrial tissue and 12% persistant diarrhea in the postoperative group needs strict individualization in therapy and requires exact knowledge on extention and biological behavior of the tumor. (author)

  10. Biological Threats

    Science.gov (United States)

    ... Workplace Plans School Emergency Plans Main Content Biological Threats Biological agents are organisms or toxins that can ... for Disease Control and Prevention . Before a Biological Threat Unlike an explosion, a biological attack may or ...

  11. Preparation and quality control of Ho-166 labelled compounds for radiotherapy

    Czech Academy of Sciences Publication Activity Database

    Kropáček, Martin; Melichar, František; Šrank, Jiří; Ventruba, Jiří; Mirzajevová, Marcela; Kraft, O.; Křížová, V.

    2006-01-01

    Roč. 5, č. 1 (2006), S95-S95. ISSN 1450-1147. [Congress of World Federation of Nuclear Medicine and Biology /9./. 22.10.2006-27.10.2006, Seoul] R&D Projects: GA AV ČR 1QS100480501 Institutional research plan: CEZ:AV0Z10480505 Keywords : holmium * radiotherapy Subject RIV: FD - Oncology ; Hematology

  12. Palliative radiotherapy: current status and future directions.

    Science.gov (United States)

    Sharma, Sonam; Hertan, Lauren; Jones, Joshua

    2014-12-01

    For nearly 100 years, palliative radiotherapy has been a time-efficient, effective treatment for patients with metastatic or advanced cancer in any area where local tumors are causing symptoms. Short courses including a single fraction of radiotherapy may be effective for symptom relief with minimal side effects and maximization of convenience for patient and family. With recent advances in imaging, surgery, and other local therapies as well as systemic cancer therapies, palliative radiotherapy has been used frequently in patients who may not yet have symptoms of advanced or metastatic cancer. In this setting, more prolonged radiotherapy courses and advanced radiotherapy techniques including intensity-modulated radiotherapy (IMRT) or stereotactic radiotherapy (SRT) may be useful in obtaining local control and durable palliative responses. This review will explore the use of radiotherapy across the spectrum of patients with advanced and metastatic cancer and delineate an updated, rational approach for the use of palliative radiotherapy that incorporates symptoms, prognosis, and other factors into the delivery of palliative radiotherapy. PMID:25499634

  13. TUMOR SUPPRESSOR GENE TP53 MUTATIONS IN ATYPICAL VASCULAR LESIONS OF THE BREAST SKIN FOLLOWING RADIOTHERAPY

    OpenAIRE

    Santi, Raffaella; Cetica, Valentina; Franchi, Alessandro; Pepi, Monica; Cesinaro, Anna Maria; Miracco, Clelia; Paglierani, Milena; De Giorgi, Vincenzo; Delfino, Chiara; Difonzo, Elisa Margherita; Pimpinelli, Nicola; Bianchi, Simonetta; Sardi, Iacopo; Santucci, Marco; Massi, Daniela

    2011-01-01

    Abstract Atypical vascular lesions (AVL) occurring at the site of radiotherapy represent an uncommon but well-documented complication in the setting of breast-conserving therapy for breast carcinoma. Although the biological behavior of AVL has been regarded to be benign, it has been suggested that AVL may represent a precursor of angiosarcoma. A better understanding of the biology of AVL is essential in order to assess appropriate patient management. The purpose of the present s...

  14. DEGRO 2009. Radiation oncology - medical physics - radiation biology. Abstracts; DEGRO 2009. Radioonkologie - Medizinische Physik - Strahlenbiologie. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-06-15

    The special volume of the journal covers the abstracts of the DEGRO 2009 meeting on radiation oncology, medical physics, and radiation biology, covering the following topics: seldom diseases, gastrointestinal tumors, radiation reactions and radiation protection, medical care and science, central nervous system, medical physics, the non-parvicellular lung carcinomas, ear-nose-and throat, target-oriented radiotherapy plus ''X'', radio-oncology - young academics, lymphomas, mammary glands, modern radiotherapy, life quality and palliative radiotherapy, radiotherapy of the prostate carcinoma, imaging for planning and therapy, the digital documentation in clinics and practical experiences, NMR imaging and tomography, hadrons - actual status in Germany, urinal tract oncology, radiotoxicity.

  15. Role of PET/CT functional imaging on constructing a tumor radiotherapeutic biological target volume

    International Nuclear Information System (INIS)

    In studies on intensity modulated radiotherapy with conventional fractionation, different radiosensitivity areas require different irradiation doses. In tumor radiotherapy areas CR, boosts in radiotherapy doses should be determined according to whether there are survived tumor cells or not. To those survived cells, CT imaging has become the key tool to delineate the radiotherapy target. Thus, the study on the construction of biological target volume with PET/CT functional imaging, which could reflect either radiosensitivity or cell proliferation-related cell metabolism, anoxia and DNA number of various cell cycle phases, is an important research area. (authors)

  16. Gold coated lanthanide phosphate nanoparticles for targeted alpha generator radiotherapy.

    Directory of Open Access Journals (Sweden)

    Mark F McLaughlin

    Full Text Available Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo α-generator targeted radiotherapies can deliver multiple α particles to a receptor site dramatically amplifying the radiation dose delivered to the target. The major challenge with α-generator radiotherapies is that traditional chelating moieties are unable to sequester the radioactive daughters in the bioconjugate which is critical to minimize toxicity to healthy, non-target tissue. The recoil energy of the (225Ac daughters following α decay will sever any metal-ligand bond used to form the bioconjugate. This work demonstrates that an engineered multilayered nanoparticle-antibody conjugate can deliver multiple α radiations and contain the decay daughters of (225Ac while targeting biologically relevant receptors in a female BALB/c mouse model. These multi-shell nanoparticles combine the radiation resistance of lanthanide phosphate to contain (225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established gold chemistry for attachment of targeting moieties.

  17. Decommissioning of Radiotherapy Facilities

    International Nuclear Information System (INIS)

    Radiotherapy units containing high activity sealed radioactive sources of 60Co or 137Cs are mainly use for medical, research or calibration applications. After several half-lives of decay, the radionuclide source has to be changed or the unit is decommissioned if no longer required. Before starting a decommissioning project it is very important to look for documents relating to any sources held or installed in equipment. In general this should be no problem because the recommended working life of such sealed radioactive sources is limited to 10 or a maximum of 15 years. These time periods are short in comparison with other facilities like research laboratories or small reactors. These documents (source certificates) will be very helpful to plan the decommissioning because they say everything about the original activity of the source at a reference date, the type of the source and the manufacturer. The next step may be to contact the machine supplier or the source manufacturer, but be aware that neither may still be in existence or may have changed their type of business. In such cases, it is recommended to contact national or international sealed source manufacturers or suppliers for help. Sometimes it is also helpful to contact colleagues in other hospitals or research centres to ask for information about specialists in this topic. In general it is not useful, and even very dangerous, to try to decommission such a unit without expert help It is essential to have specialist tools and shielded containers to recover the source out of the unit. It is strongly recommended to invite the source removal specialist for a site visit to review the situation before starting any decommissioning process. A further problem can occur, if the source must be transported to a national storage centre or even an international storage facility, as the source must be packaged to meet international transport requirements. The end state of such a project should be an empty room where the

  18. Potential benefits of π meson beams for radiotherapy

    International Nuclear Information System (INIS)

    After a brief survey of the history of the discovery and production of mesons, their main characteristics and the principle of their production are summarized. The interactions with matter of the positive, negative and neutral forms are pointed out at the levels of target, beams transfer and biological tissues. The attention is especially drawn on the characteristics of energy deposition by particles issued from disintegrations produced by negative pions at the end of their tracks; these characteristics materialize the interest for radiotherapy by negative pions

  19. Response of human hair cortical cells to fractionated radiotherapy

    International Nuclear Information System (INIS)

    Hair cortical cell counting (HCCC) represents a non-invasive, in-vivo measure of cell kill in the human integument. Sixty-six patients undergoing conventionally fractionated, external beam radiotherapy for early stage carcinoma of the prostate had groin hair samples counted. This technique is a sensitive and reproducible measure of radiation effect and may have applicability as an in-vivo prediction tool or in the field of biological dosimetry. A repopulative follicular response occurring at 3-4 weeks may explain flattening of the dose response curve

  20. Psychosocial effects of radiotherapy after mastectomy

    International Nuclear Information System (INIS)

    Psychosocial morbidity was measured in 47 patients who received postoperative radiotherapy and in 38 who received no further treatment after mastectomy. Roughly one third of all patients experienced depression or anxiety. One month after operation, before radiotherapy, there were no significant differences between the two groups in any of the measures of psychosocial morbidity. Knowledge of impending treatment did not seem to influence morbidity. At three months patients who had completed radiotherapy had significantly more somatic symptoms and social dysfunction than those not so treated. At six months the radiotherapy group continued to show more somatic symptoms, but a year after operation there were no significant differences between the groups. Although several patients who received radiotherapy were upset by their treatment, the study failed to confirm that depression and anxiety were commoner among those given radiotherapy than among patients given no further treatment. (author)

  1. Gel dosimetry for conformal radiotherapy

    International Nuclear Information System (INIS)

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

  2. Proton Radiotherapy for Pediatric Sarcoma

    International Nuclear Information System (INIS)

    Pediatric sarcomas represent a distinct group of pathologies, with approximately 900 new cases per year in the United States alone. Radiotherapy plays an integral role in the local control of these tumors, which often arise adjacent to critical structures and growing organs. The physical properties of proton beam radiotherapy provide a distinct advantage over standard photon radiation by eliminating excess dose deposited beyond the target volume, thereby reducing both the dose of radiation delivered to non-target structures as well as the total radiation dose delivered to a patient. Dosimetric studies comparing proton plans to IMRT and 3D conformal radiation have demonstrated the superiority of protons in numerous pediatric malignancies and data on long-term clinical outcomes and toxicity is emerging. In this article, we review the existing clinical and dosimetric data regarding the use of proton beam radiation in malignant bone and soft tissue sarcomas

  3. Radiotherapy for symptomatic vertebral hemangioma

    International Nuclear Information System (INIS)

    Purpose: Assessment of treatment results of symptomatic vertebral hemangiomas and review of the literature. Patients and Methods: Ten patients treated between 1974 to 1997 were retrospectively analyzed. Efficacy of treatment was determined according to improvement of pain and/or neurological symptoms. Results: Improvement was achieved in 8 of 10 patients. The initially existing neurological symptoms of 3 patients disappeared completely in 2 cases and improved in 1 case. Acute side effects were slight. Late side effects were not seen. A dose-effect relationship could not be assessed. There was no relapse. Conclusion: Radiotherapy with 30 Gy for symptomatic vertebral angioma as primary therapy is indicated. In case of neurological symptoms a radiotherapy after operative therapy is recommendable even if the patient is free of symptoms to prevent progress or relapse. (orig.)

  4. Stereotactic radiotherapy for vestibular schwannoma

    DEFF Research Database (Denmark)

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno;

    2014-01-01

    BACKGROUND: Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy. OBJECTIVES: To assess...... the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL...... resection or any other possible treatment or combination of treatments in patients with a cerebellopontine angle tumour up to 3 cm in diameter, presumed to be a vestibular schwannoma. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by The Cochrane Collaboration. MAIN...

  5. Radiotherapy in osseous metastasizing carcinoid

    International Nuclear Information System (INIS)

    In an 51-year old patient with a disseminately metastasizing bronchus carcinoid, percutaneous radiotherapy was employed as a palliative measure against most severe pain in the region of bone metastases. In all irradiated regions (entire vertebral column and both shoulders) good pain relief was achieved in 2 weeks, lasting until the end of the follow-up period (18 months after irradiation), by application of 30 Gy photon radiation. Correlated with the subjective pain relief was a reduction of the required quantity of analgesics, a reduction of the greatly increased activity of alkaline phosphatase in the serum, and roentgenological sclerosing of the metastatic bone lesions. This case report is intended to point to the possibility of employing radiotherapy in similar cases where medication has finally proved futile, since the rare reports in literature are mostly negative. (orig.)

  6. Proton Radiotherapy for Pediatric Sarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Ladra, Matthew M.; Yock, Torunn I., E-mail: tyock@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA 02114 (United States)

    2014-01-14

    Pediatric sarcomas represent a distinct group of pathologies, with approximately 900 new cases per year in the United States alone. Radiotherapy plays an integral role in the local control of these tumors, which often arise adjacent to critical structures and growing organs. The physical properties of proton beam radiotherapy provide a distinct advantage over standard photon radiation by eliminating excess dose deposited beyond the target volume, thereby reducing both the dose of radiation delivered to non-target structures as well as the total radiation dose delivered to a patient. Dosimetric studies comparing proton plans to IMRT and 3D conformal radiation have demonstrated the superiority of protons in numerous pediatric malignancies and data on long-term clinical outcomes and toxicity is emerging. In this article, we review the existing clinical and dosimetric data regarding the use of proton beam radiation in malignant bone and soft tissue sarcomas.

  7. Fingerprints identification of radiotherapy patients

    International Nuclear Information System (INIS)

    The identification of patient plays a key role in the quality and safety of radiotherapy. It does impact on all professional staff and on patients. After the regulatory authority approval (Cnil), a pilot study has been performed on 1901 patients. Acceptance has been very high (> 93%) with a low risk of mis-identification (< 0.1%). The next step will be to implement and test a bimodal system in order to improve registration capacity and sensitivity. (authors)

  8. Natural history of intracranial meningioma after radiotherapy

    International Nuclear Information System (INIS)

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

  9. Experiment on radiotherapy of postnatal mastitis

    International Nuclear Information System (INIS)

    The results of radiotherapy of postnatal mastitis in 78 women are presented. It is shown that the radiotherapy is the method of choice. Application of radiotherapy at different stages of disease promotes either complete resolution of infiltration (1-2 irradiations) or stipulates the decrease in temperature, abatement of pains and improvement of general state (at the presence of purulent fusion of mammary tissue). X-ray therapy of postnatal mastitis has does not affect the lactational function of mammary gland

  10. Single fraction radiotherapy versus multiple fraction radiotherapy for bone metastases in prostate cancer patients: comparative effectiveness

    International Nuclear Information System (INIS)

    External beam radiotherapy (EBRT) is an effective treatment for symptomatic bone metastases from a variety of primary malignancies. Previous meta-analyses and systematic reviews have reported on the efficacy of EBRT on bone metastases from multiple primaries. This review is focused on the comparative effectiveness of single fraction radiotherapy versus multiple fraction radiotherapy for bone metastases in prostate cancer patients

  11. Risk-adapted targeted intraoperative radiotherapy versus whole-breast radiotherapy for breast cancer

    DEFF Research Database (Denmark)

    Vaidya, Jayant S; Wenz, Frederik; Bulsara, Max;

    2014-01-01

    The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy (TARGIT) versus fractionated external beam radiotherapy (EBRT) for breast cancer. We report 5-year results for local recurrence and the first analysis of overall survival....

  12. Patient Radiation Protection in Radiotherapy

    International Nuclear Information System (INIS)

    The Role of Radiotherapy is treatment modalities for cancer which is generally assumed that 50 to 60% of cancer patients will benefit from radiotherapy. It constitutes a peaceful application of ionizing radiation and an essential part of cancer management. The two aims of radiation protection Prevention is of deterministic effect and Reduction of the probability of stochastic effects. The Shielding fundamentals is to limit radiation exposure of staff, patients, visitors and the public to acceptable levels it also optimize protection of patients, staff and the public. Diagnosis is important for target design and the dose required for cure or palliation while Simulator is often used twice in the radiotherapy process where Patient data acquisition - target localization, contours, outlines and Verification. The Prescription is the responsibility of individual clinicians, depending on the patient’s condition, equipment available, experience and training. An ultimate check of the actual treatment given can only be made by using in vivo dosimetry. Treatment records must be kept of all relevant aspects of the treatment – including Session and Summary Record information, Records all treatment parameters, Dose Calculations and Dose Measurements

  13. Rectal dose reduction with IMRT for prostate radiotherapy

    International Nuclear Information System (INIS)

    Dose escalation in radiation therapy has led to increased control rates with some clinical trial evidence that rectal toxicity may be reduced when using intensity-modulated radiotherapy (IMRT) over 3D conformal radiotherapy (3DCRT) for dose-escalated prostate radiotherapy. However, IMRT for prostate patients is not yet standard in many Australian radiation oncology centres. This study investigates dosimetric changes that can be observed between IMRT and 3DCRT in prostate radiotherapy. Fifteen patients were selected for analysis. Two target definitions were investigated – prostate-only and prostate plus seminal vesicles (p + SVs). A five-field 3DCRT and seven-field IMRT plan were created for each patient and target definition. The planning target volume coverage was matched for both plans. Doses to the rectum, bladder and femoral heads were compared using dose volume histograms. The rectal normal tissue complication probabilities (NTCPs) were calculated and compared for the 3DCRT and IMRT plans. The delivery efficiency was investigated. The IMRT plans resulted in reductions in the V25, V50, V60, V70 and V75 Gy values for both the prostate-only and p + SVs targets. Rectal NTCP was reduced with IMRT for three different sets of model parameters. The reductions in rectal dose and NTCP were much larger for the p + SVs target. Delivery of IMRT plans was less efficient than for 3DCRT plans. IMRT resulted in superior plans based on dosimetric and biological endpoints. The dosimetric gains with IMRT were greater for the more complex p + SVs target. The gains made came at the cost of decreased delivery efficiency.

  14. Immediate side effects of large fraction radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Devereux, S.; Hatton, M.Q.F.; Macbeth, F.R. [Glasgow Western Infirmary (United Kingdom)

    1997-09-01

    The use of hypofractionated radiotherapy regiments is becoming more widely recognized in the palliation of non-small cell lung carcinoma (NSCLC). Anecdoctal reports of chest pain, rigors and fevers in the hours that follow radiotherapy led us to perform a survey estimating the frequency and severity of these symptoms following treatment to the thorax. We conclude that patients receiving palliative radiotherapy for bronchial carcinoma often develop significant symptoms in the hours following treatment. The timing and duration suggest a relationship with the radiotherapy, and we feel that patients should be warned of the possible occurrence of these symptoms. (author).

  15. Targeting IAP proteins in combination with radiotherapy

    International Nuclear Information System (INIS)

    The efficacy of radiotherapy critically depends on the activation of intrinsic cell death programs in cancer cells. This implies that evasion of cell death, a hallmark of human cancers, can contribute to radioresistance. Therefore, novel strategies to reactivate cell death programs in cancer cells are required in order to overcome resistance to radiotherapy. Since Inhibitor of Apoptosis (IAP) proteins are expressed at high levels in multiple cancers and block cell death induction at a central point, therapeutic targeting of IAP proteins represents a promising approach to potentiate the efficacy of radiotherapy. The current review discusses the concept of targeting IAP proteins in combination with radiotherapy

  16. Otologic disorders following radiotherapy for nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Radiotherapy is widely accepted as the first choice for nasopharyngeal carcinoma. Delayed otitis of both external and middle ears is sometimes seen as a complication after radiotherapy for head and neck cancer, especially for nasopharyngeal carcinoma. They are usually hard to manage and some produces cochlear damages, finally resulting in a sensorineural hearing loss. However, these otologic disorders are tends to be overlooked, because physicians pay less attention to them than the concerning for cancer recurrence. Therefore, studies on the otologic disorders following radiotherapy are lacking. In this study, we analyzed 24 nasopharyngeal carcinoma cases retrospectively to clarify the incidence of otologic disorders induced by radiotherapy. (author)

  17. Guide of external radiotherapy procedures 2007

    International Nuclear Information System (INIS)

    This work aims at participating in the permanent optimization of the returned medical service and the ratio profit-risk. This first version of the guide of external radiotherapy procedures 2007 processes only techniques of external radiotherapy, by opposition to the techniques of brachytherapy which use radioactive sources (iridium192, iodine125, cesium137) placed in the contact of the tumor to be irradiated. Only, also, will be considered the irradiations of the most frequent cunning(malignant) tumors with the exception of the radiotherapy of the mild pathologies and the re-irradiations after a first radiotherapy. The first part is shared in eight chapters as follow: introduction, the steps of a treatment by radiotherapy, infrastructure, equipment and human resources, radiobiology mechanism of action of ionising radiations in radiotherapy, dose in radiotherapy, quality of treatment and radiation protection of patients in radiotherapy, prevention and risk management in radiotherapy, quality assurance and radiation protection for the pediatrics cancers and the case of pregnant women. The second part gives the tumoral localizations and the procedures; the third part is a glossary and different annexes such regulations and legislative texts. (N.C.)

  18. The role of radiotherapy in hospice care

    International Nuclear Information System (INIS)

    The aim of palliative radiotherapy for the terminally ill is to improve the quality of the remaining span of life. From November 1982 to September 1987, 69 patients in the Seirei Hospice have been treated with such radiotherapy, and symptomatic relief was obtained in 64% of these patients. Radiotherapy also proved useful in achieving an improvement in their performance status. While the aim of hospice care is not directed towards treatment of the underlying disease, the use of radiotherapy is considered to have an important role in hospice care. (author)

  19. Role of radiotherapy in hospice care

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tetsuo; Sugiyama, Akira; Shimizu, Teppei; Ichinohe, Kenji; Teshima, Takeshi; Kaneko, Masao; Hara, Yoshio; Chihara, Satoshi.

    1989-01-01

    The aim of palliative radiotherapy for the terminally ill is to improve the quality of the remaining span of life. From November 1982 to September 1987, 69 patients in the Seirei Hospice have been treated with such radiotherapy, and symptomatic relief was obtained in 64% of these patients. Radiotherapy also proved useful in achieving an improvement in their performance status. While the aim of hospice care is not directed towards treatment of the underlying disease, the use of radiotherapy is considered to have an important role in hospice care.

  20. Every second cancer patient receives radiotherapy

    International Nuclear Information System (INIS)

    Radiotherapy to treat cancer was given for the first time exactly one hundred years ago. Today, radiotherapy and surgery are the two main modes of treating cancer. One in two cancer patients receives radiotherapy at some point during the course of treatment for the disease. Radiotherapy is applied most commonly in cases where surgery is not possible. Moreover, these two modes of treatment are often used together to supplement each other. About half of new cancer cases detected today can be ordered. The estimate given by the EU for cancers cured is 45 per cent, which is divided between the various treatment modes as follows: surgery 22 %, radiotherapy 12 %, surgery plus radiotherapy 6 %, and drug therapy 6 %. In addition to curative treatment, radiotherapy plays a crucial role in palliative treatment, i.e. treatment that alleviates symptoms. The sensitivity of malignant tumours to radiotherapy varies over a wide range; the same is true for healthy tissues. Radiotherapy can only be used to cure a tumour that is more sensitive to radiation than the surrounding healthy tissue. The tumour must also be sufficiently small in size and limited to a relatively small area. (orig.)

  1. Breast cancer biology for the radiation oncologist

    International Nuclear Information System (INIS)

    This is the first textbook of its kind devoted to describing the biological complexities of breast cancer in a way that is relevant to the radiation oncologist. Radiation Oncology has long treated breast cancer as a single biological entity, with all treatment decisions being based on clinical and pathologic risk factors. We are now beginning to understand that biological subtypes of breast cancer may have different risks of recurrence as well as different intrinsic sensitivity to radiotherapy. Multi-gene arrays that have for years been used to predict the risk of distant recurrence and the value of systemic chemotherapy may also have utility in predicting the risk of local recurrence. Additionally, the targeted agents used to treat breast cancer may interact with radiotherapy in ways that can be beneficial or undesirable. All of these emerging issues are extensively discussed in this book, and practical evidence-based treatment recommendations are presented whenever possible.

  2. Breast cancer biology for the radiation oncologist

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Jonathan [Northwestern Univ., Chicago, IL (United States). Dept. of Radiation Oncology; Small, William [Loyola Univ. Chicago, Maywood, IL (United States). Stritch School of Medicine, Cardianl Bernardin Cancer Center; Woloschak, Gayle E. (ed.) [Northwestern Univ. Feinberg, Chicago, IL (United States). School of Medicine

    2015-10-01

    This is the first textbook of its kind devoted to describing the biological complexities of breast cancer in a way that is relevant to the radiation oncologist. Radiation Oncology has long treated breast cancer as a single biological entity, with all treatment decisions being based on clinical and pathologic risk factors. We are now beginning to understand that biological subtypes of breast cancer may have different risks of recurrence as well as different intrinsic sensitivity to radiotherapy. Multi-gene arrays that have for years been used to predict the risk of distant recurrence and the value of systemic chemotherapy may also have utility in predicting the risk of local recurrence. Additionally, the targeted agents used to treat breast cancer may interact with radiotherapy in ways that can be beneficial or undesirable. All of these emerging issues are extensively discussed in this book, and practical evidence-based treatment recommendations are presented whenever possible.

  3. Clinical study and numerical simulation of brain cancer dynamics under radiotherapy

    Science.gov (United States)

    Nawrocki, S.; Zubik-Kowal, B.

    2015-05-01

    We perform a clinical and numerical study of the progression of brain cancer tumor growth dynamics coupled with the effects of radiotherapy. We obtained clinical data from a sample of brain cancer patients undergoing radiotherapy and compare it to our numerical simulations to a mathematical model of brain tumor cell population growth influenced by radiation treatment. We model how the body biologically receives a physically delivered dose of radiation to the affected tumorous area in the form of a generalized LQ model, modified to account for the conversion process of sublethal lesions into lethal lesions at high radiation doses. We obtain good agreement between our clinical data and our numerical simulations of brain cancer progression given by the mathematical model, which couples tumor growth dynamics and the effect of irradiation. The correlation, spanning a wide dataset, demonstrates the potential of the mathematical model to describe the dynamics of brain tumor growth influenced by radiotherapy.

  4. Biological radiation effects

    International Nuclear Information System (INIS)

    The book covers all aspects of biological radiation effects and provides the fundamental basis for understanding the necessity of radiation protection as well as applications in radiotherapy. The physical basis is dealt with in some detail, and the effects at the subcellular and the cellular level are thoroughly discussed, taking into account modern developments and techniques. The effects on the human organism are reviewed, both from the point of view of applications in medicine as well as with regard to radiation hazards (teratogenic, gonadal and carcinogenic effects). It can be used by graduate students as an introduction and as a source book for all who want to become acquainted with this important field. It is an extended version of the original German book containing updated information and new material. (orig.) With 273 figs

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-03-15

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

  6. Radiotherapy and Brachytherapy : Proceedings of the NATO Advanced Study Institute on Physics of Modern Radiotherapy & Brachytherapy

    CERN Document Server

    Lemoigne, Yves

    2009-01-01

    This volume collects a series of lectures presented at the tenth ESI School held at Archamps (FR) in November 2007 and dedicated to radiotherapy and brachytherapy. The lectures focus on the multiple facets of radiotherapy in general, including external radiotherapy (often called teletherapy) as well as internal radiotherapy (called brachytherapy). Radiotherapy strategy and dose management as well as the decisive role of digital imaging in the associated clinical practice are developed in several articles. Grouped under the discipline of Conformal Radiotherapy (CRT), numerous modern techniques, from Multi-Leaf Collimators (MLC) to Intensity Modulated RadioTherapy (IMRT), are explained in detail. The importance of treatment planning based upon patient data from digital imaging (Computed Tomography) is also underlined. Finally, despite the quasi- totality of patients being presently treated with gamma and X-rays, novel powerful tools are emerging using proton and light ions (like carbon ions) beams, bound to bec...

  7. Evaluation of Thyroid Disorders During Head-and-Neck Radiotherapy by Using Functional Analysis and Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seyed Rabie [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Edraki, Hamid Reza [Department of Radiology, Panzdahe-Khordad Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2012-05-01

    Purpose: To evaluate thyroid function and vascular changes during radiotherapy for patients with head and neck cancer. Methods and Materials: Fifty patients treated with primary or postoperative radiotherapy for various cancers in the head and neck region were prospectively evaluated. The serum samples (triiodothyronine [T3], thyroxine [T4], thyroid-stimulating hormone [TSH], free triiodothyronine [FT3], and free thyroxine [FT4]), the echo level of the thyroid gland, and color Doppler ultrasonography (CDU) parameters of the right inferior thyroid artery (RITA) of the patients were measured before and at regular intervals during radiotherapy. The thyroid gland dose-volume histograms of the patients were derived from their computed tomography-based treatment plans. Results: There was a significant fall in TSH level (p < 0.0001) but an increase in FT4 (p < 0.0001) and T4 (p < 0.022) levels during the radiotherapy course. The threshold dose required to produce significant changes was 12 Gy (Biologically Effective Dose in 2-Gy fractions, BED{sub 2}). There were significant rises in the patients' pulsatility index, resistive index, peak systolic velocity, blood volume flow levels, and RITA diameter (p < 0.0001), as detected by CDU during radiotherapy, compared to those parameters measured before the treatment. Hypoechogenicity and irregular echo patterns (p < 0.0001) were seen during radiotherapy compared to those before treatment. There was significant Pearson's correlation between the CDU parameters and T4, FT4, and TSH levels. Conclusions: Radiation-induced thyroiditis is regarded as primary damage to the thyroid gland. Thyroiditis can subsequently result in hypothyroidism or hyperthyroidism. Our results demonstrated that changes in thyroid vessels occur during radiotherapy delivered to patients. Vessel changes also can be attributed to the late effect of radiation on the thyroid gland. The hypoechogenicity and irregular echo patterns observed in patients

  8. Radiotherapy versus combined modality in early stages

    DEFF Research Database (Denmark)

    Specht, L.; Carde, P.; Mauch, P.; Magrini, S.M.; Santarelli, M.T.

    In early stage Hodgkin's disease the optimal choice of treatment for the individual patient is still an unresolved issue. So far, twenty-two randomized trials of radiotherapy alone versus radiotherapy plus combination chemotherapy have been carried out worldwide. The preliminary results of a glob...

  9. Treatment machines for external beam radiotherapy

    International Nuclear Information System (INIS)

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

  10. Radiological protection of the radiotherapy patient?

    International Nuclear Information System (INIS)

    We propose that the system and concepts of radiation protection should not be used with reference to radiotherapy patients. We justify this on conceptual grounds. The patient undergoing radiotherapy procedures, as prescribed by the medical practitioner, is protected by the quality assurance system legally required for medical exposures. (author)

  11. Fast neutron radiotherapy: for equal or for better

    International Nuclear Information System (INIS)

    The renewed application of fast neutrons in clinical radiotherapy has been stimulated by fundamental radiobiological findings. The biological effects of high LET radiation, including fast neutrons, are different from those obtained with x rays in at least three respects: the oxygen enhancement ratio, the sensitivity of cells at different phases of the cell cycle, and the contribution of sublethal damage to cell reproductive death. Furthermore, wide variations in relative biological effectiveness (RBE) have been observed for different tumors and normal tissues. Measurements of volume changes in human pulmonary metastases indicate that the RBE for slowly growing tumors which are generally well-differentiated is higher than that for poorly differentiated lesions. Six thousand patients have now been treated with fast neutron beams. The results of the clinical applications vary according to the method of application and to the type of cancer involved: treatment of inoperable malignancies of the salivary gland is very encouraging: the therapeutic gain is rather small for bladder and rectal cancers, soft tissue sarcomas and advanced carcinomas of the cervix; the responses of brain tumors are very disappointing. Most neutron radiotherapy applications have been less than optimal because of inadequate physical and technical conditions. Despite these difficulties, some interesting clinical data have become available. Due to the technical shortcomings, the possible advantages of fast neutrons are probably underestimated for many tumor sites. Well-designed clinical trials, preferably performed with high energy cyclotrons in clinical environments, will provide a decisive answer to the question of the usefulness of the new radiation modality

  12. Minimizing second cancer risk following radiotherapy: current perspectives

    International Nuclear Information System (INIS)

    Secondary cancer risk following radiotherapy is an increasingly important topic in clinical oncology with impact on treatment decision making and on patient management. Much of the evidence that underlies our understanding of secondary cancer risks and our risk estimates are derived from large epidemiologic studies and predictive models of earlier decades with large uncertainties. The modern era is characterized by more conformal radiotherapy technologies, molecular and genetic marker approaches, genome-wide studies and risk stratifications, and sophisticated biologically based predictive models of the carcinogenesis process. Four key areas that have strong evidence toward affecting secondary cancer risks are 1) the patient age at time of radiation treatment, 2) genetic risk factors, 3) the organ and tissue site receiving radiation, and 4) the dose and volume of tissue being irradiated by a particular radiation technology. This review attempts to summarize our current understanding on the impact on secondary cancer risks for each of these known risk factors. We review the recent advances in genetic studies and carcinogenesis models that are providing insight into the biologic processes that occur from tissue irradiation to the development of a secondary malignancy. Finally, we discuss current approaches toward minimizing the risk of radiation-associated secondary malignancies, an important goal of clinical radiation oncology

  13. The Confluence of Stereotactic Ablative Radiotherapy and Tumor Immunology

    Directory of Open Access Journals (Sweden)

    Steven Eric Finkelstein

    2011-01-01

    Full Text Available Stereotactic radiation approaches are gaining more popularity for the treatment of intracranial as well as extracranial tumors in organs such as the liver and lung. Technology, rather than biology, is driving the rapid adoption of stereotactic body radiation therapy (SBRT, also known as stereotactic ablative radiotherapy (SABR, in the clinic due to advances in precise positioning and targeting. Dramatic improvements in tumor control have been demonstrated; however, our knowledge of normal tissue biology response mechanisms to large fraction sizes is lacking. Herein, we will discuss how SABR can induce cellular expression of MHC I, adhesion molecules, costimulatory molecules, heat shock proteins, inflammatory mediators, immunomodulatory cytokines, and death receptors to enhance antitumor immune responses.

  14. To boost or not boost in radiotherapy

    International Nuclear Information System (INIS)

    The aim of this paper it to analyse and discuss standard definition of the 'boost' procedure in relation to clinical results and new forms of the boost designed on physical and radiobiological bases. Seventeen sets of clinical data including over 5000 cases cancer with different tumour stages and locations and treated with various forms of 'boost' method have been subtracted from literature. Effectiveness of boost is analyzed regarding its place in combined treatment, timing and subvolume involved. Radiobiological parameter of D10 and normalization method for biologically equivalent doses and dose intensity are used to simulated cold and not subvolumes (hills and dales) and its influence of effectiveness on the boost delivery. Sequential and concomitant boost using external irradiation, although commonly used, offers LTC benefit lower than expected. Brachytherapy, intraoperative irradiation and concurrent chemotherapy boost methods appear more effective. Conformal radiotherapy, with or without dose-intensity modulation, allows heterogeneous increase in dose intensity within the target volume and can be used to integrate the 'boost dose' into baseline treatment (Simultaneous Integrated Boost and SIB). Analysis of interrelationships between boost-dose; boost volume and its timing shows that a TCP benefit from boosting can be expected when a relatively large part of the target volume is involved. Increase in boost dose above 1.2-1.3 of baseline dose using 'standard' methods does not substantially further increase the achieved TCP benefit unless hypoxic cells are a problem. Any small uncertainties in treatment planning can ruin all potential beneficial effect of the boost. For example, a 50% dose deficit in a very small (e.g. 1%) volume of target can decrease TCP to zero. Therefore boost benefits should be carefully weighed against any risk of cold spots in the target volume. Pros and cons in discussion of the role of boost in radiotherapy lead to the important

  15. Conformal radiotherapy: revolution or evolution?

    International Nuclear Information System (INIS)

    The advantage the most clearly known of a conformal approach takes place in the protection of sane tissues. A randomized study comparing classical radiotherapy and conformal (defined with the use of masks) has noticed a significant reduction of the delayed rectal toxicity after conformal irradiation for patients suffering of prostate tumor. This benefit has been observed with a simple technique (three beams) and a dose not really high (66 Gy). It could bring a safety margin in the case of increasing of the tumor dose. (N.C.)

  16. Quality and safety in radiotherapy

    CERN Document Server

    Pawlicki, Todd

    2010-01-01

    The first text to focus solely on quality and safety in radiotherapy, this work encompasses not only traditional, more technically oriented, quality assurance activities, but also general approaches of quality and safety. It includes contributions from experts both inside and outside the field to present a global view. The task of assuring quality is no longer viewed solely as a technical, equipment-dependent endeavor. Instead, it is now recognized as depending on both the processes and the people delivering the service. Divided into seven broad categories, the text covers: Quality Management

  17. Successful radiotherapy of facial angiosarcoma.

    Science.gov (United States)

    Gkalpakiotis, S; Arenberger, P; Vohradnikova, O; Arenbergerova, M

    2008-11-01

    Cutaneous angiosarcoma of the face and scalp is a rare malignant vascular tumor that affects mostly Caucasian elderly males. At present, connections concerning the etiology of this neoplasm with radiation therapy, exposure to environmental carcinogens and chronic lymphedema have been described. Due to the difficult histologic evaluation, high local recurrence and tendency to early metastasing, angiosarcoma poses generally a very poor prognosis. We report the case of an 80-year-old patient who experienced successful removal of large, exophytic growing angiosarcoma of the face achieved with radiotherapy with long-term relapse-free survival. PMID:18986458

  18. Family physicians' perspectives regarding palliative radiotherapy

    International Nuclear Information System (INIS)

    Purpose: To assess family physicians' views on common indications for palliative radiotherapy and to determine whether this influences patient referral. Methods and materials: A 30-item questionnaire evaluating radiotherapy knowledge and training developed at the Ottawa Regional Cancer Centre (ORCC) was mailed to a random sample of 400 family physicians in eastern Ontario, Canada. The completed surveys were collected and analyzed, and form the basis of this study. Results: A total of 172 completed surveys were received for a net response rate of 50% among practicing family physicians. Almost all of the physicians (97%) had recently seen cancer patients in their offices, with 85% regularly caring for patient with advanced cancer. Fifty-four percent had referred patients in the past for radiotherapy and 53% had contacted a radiation oncologist for advice. Physicians who were more knowledgeable about the common indications for palliative radiotherapy were significantly more likely to refer patients for radiotherapy (P<0.01). Inability to contact a radiation oncologist was correlated with not having referred patients for radiotherapy (P<0.01). Only 10% of the physicians had received radiotherapy education during their formal medical training. Conclusions: Many of the family physicians surveyed were unaware of the effectiveness of radiotherapy in a variety of common palliative situations, and radiotherapy referral was correlated with knowledge about the indications for palliative radiotherapy. This was not surprising given the limited education they received in this area and the limited contact they have had with radiation oncologists. Strategies need to be developed to improve continuing medical education opportunities for family physicians and to facilitate more interaction between these physicians and radiation oncologists

  19. Quality control programme for radiotherapy

    International Nuclear Information System (INIS)

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

  20. Optimization of human cancer radiotherapy

    CERN Document Server

    Swan, George W

    1981-01-01

    The mathematical models in this book are concerned with a variety of approaches to the manner in which the clinical radiologic treatment of human neoplasms can be improved. These improvements comprise ways of delivering radiation to the malignan­ cies so as to create considerable damage to tumor cells while sparing neighboring normal tissues. There is no unique way of dealing with these improvements. Accord­ ingly, in this book a number of different presentations are given. Each presentation has as its goal some aspect of the improvement, or optimization, of radiotherapy. This book is a collection of current ideas concerned with the optimization of human cancer radiotherapy. It is hoped that readers will build on this collection and develop superior approaches for the understanding of the ways to improve therapy. The author owes a special debt of thanks to Kathy Prindle who breezed through the typing of this book with considerable dexterity. TABLE OF CONTENTS Chapter GENERAL INTRODUCTION 1. 1 Introduction 1...

  1. ORO dental complications of radiotherapy

    International Nuclear Information System (INIS)

    Radiation and radioactivity were discovered more than 100 years ago. Since then, radiation has become important in cancer treatment. Approximately one million people will develop invasive cancer each year. Of these, 40% will receive curative benefit from surgery, radiation, chemotherapy, or a combination modality. Normal body tissues vary in their response to radiation. As with tumors, normal tissues in which cells are quickly dividing may be affected. This causes some of the side effects of radiation treatment. Since radiation is a local treatment, side effects depend on the area of the body being treated. The early effects of radiation may be seen a few days or weeks after treatments have started and may go on for several weeks after treatments have ended. Other effects may not show up until months, or even years, later. As radiotherapy is a viable treatment modality for head and neck cancer, however a wide range of potentially debilitating dental complications may accompany this treatment. The orofacial tissues of dental significance that may be affected by head and neck radiotherapy are the salivary glands, mucous membranes, taste buds, bone and teeth. (author)

  2. Craniospinal radiotherapy in adult medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Selek, U.; Zorlu, F.; Hurmuz, P.; Cengiz, M.; Gurkaynak, M. [Hacettepe Univ., Ankara (Turkey). Dept. of Radiation Oncology; Turker, A. [Hacettepe Univ., Ankara (Turkey). Dept. of Internal Medicine; Soylemezoglu, F. [Hacettepe Univ., Ankara (Turkey). Dept. of Pathology

    2007-05-15

    Purpose: To evaluate the outcome and prognostic factors of adult patients with medulloblastoma. Patients and Methods: 26 adult medulloblastoma patients with a median age of 27 were subjected to craniospinal radiotherapy. A dose of 30.6 Gy with 1.8 Gy/fraction/day was prescribed to M0 patients, while 36 Gy were to be applied in patients with positive cerebrospinal liquor findings. The posterior fossa was boosted to 54 Gy. While 20 patients underwent external-beam radiotherapy alone, only six received sequential adjuvant chemotherapy. Results: Male/female ratio was 1.2. Preradiotherapy Karnofsky performance status was recorded as median 100%. 50% were classified as poor risk (n = 10, subtotal resection; n = 3, M+). The median follow-up time was 46.5 months. The 5-year actuarial survival rates for recurrence-free, distant metastasis-free, disease-free, and overall survival were 82.5%, 90.8%, 73.5%, and 89.7%, respectively. Patient characteristics, treatment factors and tumor characteristics failed to show any significance in univariate analysis. Grade 3 or 4 late morbidities were not observed. Conclusion: Yet, the current standard of care seems to remain craniospinal irradiation after maximal surgical resection of the primary neoplasm without clear indications for adjuvant chemotherapy. (orig.)

  3. Unstable chromosome aberrations on peripheral blood lymphocytes from patients with cervical uterine cancer following radiotherapy

    International Nuclear Information System (INIS)

    Absorbed dose determination is an important step for risk assessment related to an exposure to ionizing radiation. However, physical dosimetry cannot be always performed, principally in the case of retrospective estimates. In this context, the use of bioindicators (biological effects) has been proposed, which defines the so-called biological dosimetry. In particular, scoring of unstable chromosomes aberrations (dicentrics, centric rings and fragments) of peripheral blood lymphocytes, while is the most reliable biological method for estimating individual exposure to ionizing radiation. In this work, blood samples from 5 patients, with cervical uterine cancer, were evaluated after partial-body radiotherapy with a source of 69 Co. For this, conventional cytogenetic method was employed, based on Giemsa coloration and fluorescence in situ hybridization, in order to correlate the frequency of unstable chromosome aberrations of blood lymphocytes with absorbed dose, as a result of the radiotherapy. A good agreement was observed between the frequency of chromosome aberrations scored and the values of dose previously calculated by physical dosimetry during patient's radiotherapy. The results presented in this work point out the importance of concerning analyses of unstable chromosome aberrations as biological dosimeter in the investigation of partial-body exposure to ionizing radiation. (author)

  4. Customized mold radiotherapy with prosthetic apparatus for oral cancers

    International Nuclear Information System (INIS)

    Eight patients (6 males, 2 females; median age, 78 years; age range, 31-94 years) were treated by mold radiotherapy with a prosthetic apparatus for oral cancers between October 2006 and March 2013. The primary sites were the tongue in 3 cases, hard palate and buccal mucosa in 2 cases each, and oral floor in 1 case. The type of treatment consisted of radical radiotherapy and palliative radiotherapy in 2 cases each, and preoperative radiotherapy, postoperative radiotherapy, additional radiotherapy after external beam radiotherapy and systemic chemotherapy in 1 case each. Patients received 40-50 Gy in 8-10 fractions with mold radiotherapy. Two patients who received radical radiotherapy showed no signs of recurrence or metastasis. The present therapy contributed to patients' palliative, postoperative, and preoperative therapy. Mold radiotherapy with a prosthetic appliance was performed safely and was a useful treatment for several types of oral cancer. (author)

  5. Psychological and physical distress of cancer patients during radiotherapy

    CERN Document Server

    König, A

    2001-01-01

    Purpose: patients undergoing radiotherapy have physical and psychological symptoms related to the underlying disease and the treatment. In order to give the best possible support to the patients, more knowledge about the amount and the changing of distress in the course of radiotherapy is of essentially importance. Methods: The distress was measured in a consecutive sample of cancer patients (n=82) undergoing radiotherapy. Each patient was given the EORTC-QLQ-C30, the HADS and a special questionnaire which ascertain radiotherapy-specific items before starting the radiotherapy, at the onset of radiotherapy, in the third week of radiotherapy and 3 weeks after the end of radiotherapy. Results: within the first week of treatment the psychological distress of the patients is increasing; 98.8 % of the patients are 'moderate distressed', 46 % 'severe distressed'. General physical symptoms seem not to be affected by the radiotherapy, there is no changing. The distress caused by the organization of the radiotherapy is...

  6. The development of radiotherapy in Slovenia

    International Nuclear Information System (INIS)

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

  7. PET and optimization of the radiotherapy: How? Which tracers? For what to make?; TEP et optimisation de la radiotherapie: comment? Quels traceurs? Pour quoi faire?

    Energy Technology Data Exchange (ETDEWEB)

    Giammarile, F. [Centre Hospitalier Lyon-Sud, Faculte de Medecine, EA 3738, Service de Medecine Nucleaire, 69 - Pierre-Benite (France)

    2007-09-15

    The objective of the radiotherapy is to deliver a maximum amount of ionizing radiation in tumour target volume while sparing the irradiation of neighbouring healthy tissues, using anatomical imaging. The addition of functional metabolic information provided by the PET- F.D.G. (fluorodeoxyglucose)made has emerged a new concept, that of biological target volume (B.T.V.). Thus, a PET-CT examination performed by a hybrid system under the same conditions that of a simulation of radiotherapy, makes it possible to obtain at the same time: the tumour staging, the acquisition of the anatomical data for dosimetry and the definition of the B.T.V.. Therefore, PET- F.D.G. will carry out a personalized treatment, with optimization of the amount of irradiation (with an aim of increasing the effectiveness of the conformational radiotherapy and of decreasing toxicity within healthy tissues) and to reduce interobserver variability in the definition of tumour target volumes. On the whole, the information provided by PET- F.D.G. can involve: suppression of the radiotherapy treatment; change of the amount of irradiation; change of dosimetry; change of therapeutic optics. Future integration of new radiopharmaceuticals, exploring the functional modifications of the tissue, will allow a better targeting of the irradiation. (author)

  8. Radiotherapy in the management of early breast cancer

    OpenAIRE

    Wang, Wei

    2013-01-01

    Radiotherapy is an indispensible part of the management of all stages of breast cancer. In this article, the common indications for radiotherapy in the management of early breast cancer (stages 0, I, and II) are reviewed, including whole-breast radiotherapy as part of breast-conserving treatment for early invasive breast cancer and pre-invasive disease of ductal carcinoma in situ, post-mastectomy radiotherapy, locoregional radiotherapy, and partial breast irradiation. Key clinical studies tha...

  9. Role of radiotherapy in melanoma management

    International Nuclear Information System (INIS)

    In melanoma, radiotherapy has generally been considered as a palliative treatment option indicated only for advanced cases or disseminated disease. In the 70s of the previous century, the technological advances in radiotherapy, linked to rapid development of computer sciences, resulted in restored interest for radiotherapy in melanoma management. Although a fundamental lack of well designed prospective and/or randomized clinical trials critically influenced the integration of radiotherapy into treatment strategies in melanoma, radiotherapy was recently recognized as an indispensable part in the multidisciplinary management of patients with melanoma. Altogether, approximately 23% of melanoma patients should receive at least one course of radiotherapy during the course of the disease. In this review, radiobiological properties of melanoma that govern the decisions for the fractionation patterns used in the treatment of this disease are described. Moreover, the indications for irradiation and the results of pertinent clinical studies from the literature, creating a rationale for the use of radiotherapy in the management of this disease, are reviewed and a brief description of radiotherapy techniques is given. Basic treatment modality in melanoma is surgery. However, whenever surgery is not radical or there are adverse prognostic factors identified on histopathological examination of resected tissue specimen, it needs to be supplemented. Also, in patients with unresectable disease or in those not being suitable for major surgery or who refuse proposed surgical intervention, other effective mode(s) of therapy need to be implemented. From this perspective, supported by clinical experiences and literature results, radiotherapy is a valuable option: it is effective and safe, in curative and palliative setting

  10. Hormone levels in radiotherapy treatment related fatigue

    International Nuclear Information System (INIS)

    Radiotherapy is known to cause debilitating treatment related fatigue. Fatigue in general is a conglomeration of psychological, physical, hematological and unknown factors influencing the internal milieu of the cancer patient. Radiotherapy can add stress at the cellular and somatic level to aggravate further fatigue in cancer patients undergoing radiotherapy. Stress related hormones might be mediating in the development of fatigue. This is an ongoing prospective study to evaluate if the hormonal profile related to stress is influenced by radiotherapy treatment related fatigue. The study was conducted from September 2002 onwards in the division of Radiotherapy and Oncology of our Medical School. Previously untreated patients with histopathology proof of malignancy requiring external beam radiotherapy were considered for this study. Selection criteria were applied to exclude other causes of fatigue. Initial fatigue score was obtained using Pipers Fatigue Score questionnaire containing 23 questions, subsequently final fatigue score was obtained at the end of radiotherapy. Blood samples were obtained to estimate the levels of ACTH, TSH, HGH, and cortisol on the final assessment. The hormone levels were compared with resultant post radiotherapy fatigue score. At the time of reporting 50 patients were evaluable for the study. The total significant fatigue score was observed among 12 (24%) patients. The individual debilitating fatigue score were behavioral severity 14 (28%), affective meaning 14(28%), Sensory 13 (26%) and cognitive mood 10 (20%) respectively. From the analysis of hormonal profile, growth hormone level > 1 ng/mL and TSH <0.03 appears to be associated with high fatigue score (though statistically not significant); whereas there was no correlation with ACTH and serum cortisol level. In our prospective study severe radiotherapy treatment related fatigue was found among our patient population. Low levels of TSH and high levels of GH appear to be associated

  11. Adjuvant radiotherapy for gallbladder cancer: A dosimetric comparison of conformal radiotherapy and intensity-modulated radiotherapy

    Institute of Scientific and Technical Information of China (English)

    Xiao-Nan Sun; Qi Wang; Ben-Xing Gu; Yan-Hong Zhu; Jian-Bin Hu; Guo-Zhi Shi; Shu Zheng

    2011-01-01

    AIM: To assess the efficacy and toxicity of conformal radiotherapy (CRT) and compare with intensity-modulated radiotherapy (IMRT) in the treatment of gallbladder cancer.METHODS: Between November 2003 and January 2010, 20 patients with gallbladder cancer were treated with CRT with or without chemotherapy after surgical resection. Preliminary survival data were collected and examined using both Kaplan-Meier and actuarial analysis. Demographic and treatment parameters were collected. All patients were planned to receive 46-56 Gy in 1.8 or 2.0 Gy per fraction. CRT planning was compared with IMRT.RESULTS: The most common reported acute toxicities requiring medication (Radiation Therapy Oncology Group, Radiation Therapy Oncology Group Grade2) were nausea (10/20 patients) and diarrhea (3/20).There were no treatment-related deaths. Compared with CRT planning, IMRT significantly reduced the volume of right kidney receiving > 20 Gy and the volume of liver receiving > 30 Gy. IMRT has a negligible impact on the volume of left kidney receiving > 20 Gy. The 95% of prescribed dose for a planning tumor volume using either 3D CRT or IMRT planning were 84.0% ±6.7%, 82.9% ± 6.1%, respectively (P > 0.05).CONCLUSION: IMRT achieves similar excellent target coverage as compared with CRT planning, while reducingthe mean liver dose and volume above threshold dose. IMRT offers better sparing of the right kidney compared with CRT planning, with a significantly lower mean dose and volume above threshold dose.

  12. Of the good usage of the radiotherapy

    International Nuclear Information System (INIS)

    After the surgery the radiotherapy is one of the most treatments used in cancers. It consists in irradiating cancer cells to prevent their reproduction and lead to their destruction. after the Epinal accident, the professor jean-Marc Cosset recounts the radiotherapy history, its efficiency in the cancers treatment but also its risks. Two examples are given, this one of Epinal with its overexposure about 20-30% for 24 patients and the case of patients having a breast cancer, developed cardiac problems after their radiotherapy because of the heart irradiation. (N.C.)

  13. Radiotherapy for solitary plasmacytoma and multiple myeloma

    International Nuclear Information System (INIS)

    Solitary plasmacytoma and multiple myeloma require a differentiated radiotherapy. The irradiation for plasmacytoma with an adequate total dose (medullary 40-50 Gy or extramedullary 50-60 Gy) leads to a high degree of local control with a low rate of side effects. In cases of multiple myeloma radiotherapy will achieve effective palliation, both in terms of recalcification as well as reduction of neurological symptoms and analgesia. In terms of analgesia the rule is the higher the single dose fraction the faster the reduction of pain. As part of a conditioning treatment prior to stem cell transplantation radiotherapy contributes to the establishment of a graft versus myeloma effect (GVM). (orig.)

  14. Radiotherapy-induced plasticity of prostate cancer mobilizes stem-like non-adherent, Erk signaling-dependent cells

    Czech Academy of Sciences Publication Activity Database

    Kyjacová, Lenka; Hubáčková, Soňa; Krejčíková, Kateřina; Strauss, R.; Hanzlíková, Hana; Dzijak, Rastislav; Imrichová, Terezie; Šímová, Jana; Reiniš, Milan; Bartek, Jiří; Hodný, Zdeněk

    2015-01-01

    Roč. 22, č. 6 (2015), s. 898-911. ISSN 1350-9047 R&D Projects: GA ČR GA13-17658S; GA MZd NT14461 EU Projects: European Commission 259893 Institutional support: RVO:68378050 Keywords : Radiotherapy-induced plasticity * prostate cancer * Erk signaling Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.184, year: 2014

  15. Radiotherapy for the prophylaxis of heterotopic ossification: A systematic review and meta-analysis of randomized controlled trials

    International Nuclear Information System (INIS)

    Introduction: Heterotopic ossification (HO) involves the formation of lamellar bone in nonosseous tissue. For HO, radiotherapy has been shown to be an effective prophylactic modality. Objective: To compare HO outcomes following radiotherapy and to investigate the comparative efficacy of preoperative versus postoperative radiotherapy. Methods: A systematic search was conducted on Ovid MEDLINE, EMBASE and Cochrane CENTRAL. Studies were included if they were randomized controlled trials (RCTs) that included patients who were prescribed prophylactic radiation for whom relevant HO progression outcomes were reported. Results: From a literature search of 528 articles, 12 RCTs were included. There was a statistically significant reduction in HO prevalence with multiple as opposed to single fraction radiotherapy (p = 0.04), however there was no statistically significant difference when examining HO progression (p = 0.34). There was no statistically significant difference in HO progression when comparing a biologically effective radiation dose (BED) of >2500 cGy versus ⩽2500 cGy (p = 0.28). As well, no statistically significant difference existed in HO progression between postoperative versus preoperative radiation (p = 0.43). Conclusion: There was no difference between postoperative or preoperative radiotherapy in preventing HO progression. There seems to be no relationship between BED greater or less than 2500 cGy and the efficacy of HO prophylaxis. Multiple fractions seem to be more effective than single fraction radiotherapy in preventing HO progression

  16. Radiotherapy for unilesional mycosis fungoides

    International Nuclear Information System (INIS)

    Purpose: To evaluate the treatment outcome and natural history of patients with the diagnosis of unilesional mycosis fungoides, treated according to a prospective radiotherapy protocol in our institution since July 1975. Methods and Materials: A total of 325 patients with the diagnosis of mycosis fungoides have been referred to the Department of Radiation Oncology at Allegheny University of Health Sciences from July 1975 through September 1996. Of these, 18 patients (5%) were classified as having unilesional mycosis fungoides and were irradiated with a curative intent using local electron fields. One patient received 22 Gy; 1 patient received 40 Gy, and the rest of the patients 30.6 Gy. Daily fractions ranged from 1.8 to 2.0 Gy. Treatments prior to radiation consisted of topical steroids and/or antifungal creams in the majority of patients, with temporary partial responses. One patient had received 2 years of topical mechlorethamine (HN2) and another patient had received topical carmustine solution (BCNU) without response prior to irradiation. Results: The responses were measured clinically; posttreatment skin biopsy was not performed routinely unless there was clinical evidence of disease persistence. Complete response rate was 100%; all treated lesions cleared completely within 4 to 8 weeks after the completion of radiation. With a median follow-up of 43 months (range 12 to 240 months), 2 relapses have occurred, 2 and 71 months after the completion of radiation. Both relapses were confined to the skin and were remote from the original site. Both relapses responded to topical application of HN2. There have been no recurrences in the irradiated field nor systemic dissemination. No long-term side effects were found related to treatment, and all the patients are currently alive and without evidence of disease. Actuarial relapse-free and overall survival at 10 years are, respectively, 86.2% and 100%. Conclusion: Unilesional mycosis fungoides has a long natural history

  17. Dosimetric comparison of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, and helical tomotherapy for lung stereotactic body radiotherapy

    OpenAIRE

    Rajesh Ashok Kinhikar; Ghadi, Yogesh G.; Priyadarshini Sahoo; Sarbani Ghosh Laskar; Deshpande, Deepak D; Shrivastava, Shyam K.; Jaiprakash Agarwal

    2015-01-01

    To compare the treatment plans generated with three-dimensional conformal radiation therapy (3DCRT), intensity modulated radiotherapy (IMRT), and helical tomotherapy (HT) for stereotactic body radiotherapy of lung, twenty patients with medically inoperable (early nonsmall cell lung cancer) were retrospectively reviewed for dosimetric evaluation of treatment delivery techniques (3DCRT, IMRT, and HT). A dose of 6 Gy per fraction in 8 fractions was prescribed to deliver 95% of the prescription d...

  18. Radiation dosimetry in radiotherapy with internal emitters

    Energy Technology Data Exchange (ETDEWEB)

    Stabin, Michael G. [Oak Ridge Inst. for Science and Education, TN (United States)

    1997-12-31

    Full text. Radiation dosimetry radionuclides are currently being labeled to various biological agents used in internal emitter radiotherapy. This talk will review the various technologies and types of radiolabel in current use, with focus on the characterization of the radiation dose to the various important tissues of the body. Methods for obtaining data, developing kinetic models, and calculating radiation doses will be reviewed. Monoclonal antibodies are currently being labeled with both alpha and beta emitting radionuclides in attempts to find effective agents against cancer. Several radionuclides are also being used as bone pain palliation agents. These agents must be studied in clinical trials to determine the biokinetics and radiation dosimetry prior to approval for general use. In such studies, it is important to ensure the collection of the appropriate kinds of data and to collect the data at appropriate time intervals. The uptake and retention of activity in all significant source organs and in excreta be measured periodically (with at least 2 data points phase of uptake or clearance). Then, correct dosimetry methods must be applied - the best available methods for characterizing the radionuclide kinetic and for estimating the dosimetry in the various organs of the body especially the marrow, should be used. Attempts are also under way to develop methods for estimating true patient-specific dosimetry. Cellular and animal studies are also. Valuable in evaluating the efficacy of the agents in shrinking or eliminating tumors; some results from such studies will also be discussed. The estimation of radiation doses to patients in therapy with internal emitters involves several complex phases of analysis. Careful attention to detail and the use of the best available methods are essential to the protection of the patient and a successful outcome

  19. Dermatologic radiotherapy and breast cancer

    International Nuclear Information System (INIS)

    This study was set up to provide quantitative data to evaluate unsubstantiated claims that improper dermatologic radiation techniques may cause breast cancer. A thin mylar window ionization rate meter placed at the location of the right breast of an Alderson-RANDO anthropomorphic phantom was used to measure direct and scatter radiation reaching the female breast during radiotherapy of the facial region (as given for acne). The results indicate that scatter doses are very small; they are influenced by radiation quality and the use or nonuse of a treatment cone. Quantitative risk estimates show that the very small risk of breast cancer induction can be reduced even further by the use of proper radiation protection measures. (orig.)

  20. External radiotherapy in thyroid cancer

    International Nuclear Information System (INIS)

    In the management of thyroid carcinoma (TC) of any histological type, surgery is the primary mode of treatment. The second modality for the management is treatment with radioactive iodine (131I), especially, when the tumor has the ability to concentrate 131I. External radiotherapy has a limited use in differentiated thyroid carcinoma (DTC). It is useful in the management of bulky residual tissue which is not completely resected, metastatic disease which does not concentrated radioiodine and as a palliative treatment for reliving pain in patients with distant metastases. The ER as an adjuvant treatment in both anaplastic and medullary carcinoma has a significant role to play and should be used more frequently than is presently being advocated and practiced

  1. Tomodensitometry images: integration in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dessy, F.; Hoornaert, M.T. [Jolimont Hospital, Haine Saint Paul (France). Cancer and Nuclear Medicine Dept.; Malchair, F. [Biomed Engineering, Boncelles (France)

    1995-12-01

    With a view to utilization of CT scan images in radiotherapy, the effective energy and the linearity of four different scanners (Siemens somatom CR, HiQS, Plus and Picker PQ 2000) and two non standard scanners, simulators with CT option (Webb 1990) (Varian Ximatron and Oldelft Simulx CT) has been measured using the method described by White and Speller in 1980. When the linearity relation in presented using the density or the electron density as the abscissa, a blurred area where two different components of equal density or electron density can have two different Hounsfield`s numbers. Using the linearity relation, the density of Rando`s lung heterogeneity is determined. We calculated a treatment planning (TP) using this value and made a comparison between the TP and the real absorbed dose with was measured using diodes. The comparison between the TP and the relative Absorbed doses showed a difference of up to 4.5%.

  2. Palliative radiotherapy for multiple myeloma

    International Nuclear Information System (INIS)

    This study reviews the experience of palliative radiotherapy to patients with multiple myeloma to define the optimal dose for pain relief. The records of 31 patients (66 sites) with multiple myeloma irradiated for palliation at Kumamoto University hospital between 1985 and 1994 were reviewed. Total dose ranged from 8 to 50 Gy, with a mean of 32.2 Gy. Symptoms included pain (78.1%), neurological abnormalities (28.1%), and palpable masses (34.3%). Symptomatic remission was obtained in 45 of 46 evaluable sites (97.8%). Complete remission of symptoms were obtained in 28.3%, and partial remission in 69.6%. According to fraction size, there was no significant difference between 3-5 Gy and 1.8-2 Gy. The incidence of complete remission increased when a total dose of more than 20 Gy was given. When the quality of life is considered, hypofractionation was recommended for the palliative radiation therapy of multiple myeloma. (author)

  3. Selecting radiotherapy dose distributions by means of constrained optimization problems.

    Science.gov (United States)

    Alfonso, J C L; Buttazzo, G; García-Archilla, B; Herrero, M A; Núñez, L

    2014-05-01

    The main steps in planning radiotherapy consist in selecting for any patient diagnosed with a solid tumor (i) a prescribed radiation dose on the tumor, (ii) bounds on the radiation side effects on nearby organs at risk and (iii) a fractionation scheme specifying the number and frequency of therapeutic sessions during treatment. The goal of any radiotherapy treatment is to deliver on the tumor a radiation dose as close as possible to that selected in (i), while at the same time conforming to the constraints prescribed in (ii). To this day, considerable uncertainties remain concerning the best manner in which such issues should be addressed. In particular, the choice of a prescription radiation dose is mostly based on clinical experience accumulated on the particular type of tumor considered, without any direct reference to quantitative radiobiological assessment. Interestingly, mathematical models for the effect of radiation on biological matter have existed for quite some time, and are widely acknowledged by clinicians. However, the difficulty to obtain accurate in vivo measurements of the radiobiological parameters involved has severely restricted their direct application in current clinical practice.In this work, we first propose a mathematical model to select radiation dose distributions as solutions (minimizers) of suitable variational problems, under the assumption that key radiobiological parameters for tumors and organs at risk involved are known. Second, by analyzing the dependence of such solutions on the parameters involved, we then discuss the manner in which the use of those minimizers can improve current decision-making processes to select clinical dosimetries when (as is generally the case) only partial information on model radiosensitivity parameters is available. A comparison of the proposed radiation dose distributions with those actually delivered in a number of clinical cases strongly suggests that solutions of our mathematical model can be

  4. The progress in radiotherapy techniques and it's clinical implications

    International Nuclear Information System (INIS)

    Three modem radiotherapy techniques were introduced into clinical practice at the onset of the 21st century - stereotactic radiation therapy (SRT), proton therapy and carbon-ion radiotherapy. Our paper summarizes the basic principles of physics, as well as the technical reqirements and clinical indications for those techniques. SRT is applied for intracranial diseases (arteriovenous malformations, acoustic nerve neuromas, brain metastases, skull base tumors) and in such cases it is referred to as stereotactic radiosurgery (SRS). Techniques used during SRS include GammaKnife, CyberKnife and dedicated linacs. SRT can also be applied for extracranial disease (non-small cell lung cancer, lung metastases, spinal and perispinal tumors, primary liver tumors, breast cancer, pancreatic tumors, prostate cancer, head and neck tumors) and in such cases it is referred to as stereotactic body radiation therapy (SBRT). Eye melanomas, skull base and cervical spine chordomas and chordosarcomas, as well as childhood neoplasms, are considered to be the classic indications for proton therapy. Clinical trials are currently conducted to investigate the usefulness of proton beam in therapy of non-small cell lung cancer, prostate cancer, head and neck tumors, primary liver and oesophageal cancer Carbon-ion radiotherapy is presumed to be more advantageous than proton therapy because of its higher relative biological effectiveness (RBE) and possibility of real-time control of the irradiated volume under PET visualization. The basic indications for carbon-ion therapy are salivary glands neoplasms, selected types of soft tissue and bone sarcomas, skull base chordomas and chordosarcomas, paranasal sinus neoplasms, primary liver cancers and inoperable rectal adenocarcinoma recurrences. (authors)

  5. Inorganic chemistry in nuclear imaging and radiotherapy: current and future directions

    OpenAIRE

    Carroll, Valerie; Demoin, Dustin W.; Hoffman, Timothy J.; Jurisson, Silvia S.

    2012-01-01

    Radiometals play an important role in diagnostic and therapeutic radiopharmaceuticals. This field of radiochemistry is multidisciplinary, involving radiometal production, separation of the radiometal from its target, chelate design for complexing the radiometal in a biologically stable environment, specific targeting of the radiometal to its in vivo site, and nuclear imaging and/or radiotherapy applications of the resultant radiopharmaceutical. The critical importance of inorganic chemistry i...

  6. South Asian Medicinal Compounds as Modulators of Resistance to Chemotherapy and Radiotherapy

    OpenAIRE

    N Rajendra Prasad; Ganesan Muthusamy; Mohana Shanmugam; Ambudkar, Suresh V.

    2016-01-01

    Cancer is a hyperproliferative disorder that involves transformation, dysregulation of apoptosis, proliferation, invasion, angiogenesis and metastasis. During the last 30 years, extensive research has revealed much about the biology of cancer. Chemotherapy and radiotherapy are the mainstays of cancer treatment, particularly for patients who do not respond to surgical resection. However, cancer treatment with drugs or radiation is seriously limited by chemoresistance and radioresistance. Vario...

  7. [(18)F]Fluoroethyltyrosine- positron emission tomography-guided radiotherapy for high-grade glioma

    OpenAIRE

    Ratib Osman; Dipasquale Giovanna; Nouet Philippe; Rouzaud Michel; Haller Guy; Casanova Nathalie; Buchegger Franz; Zilli Thomas; Weber Damien C; Zaidi Habib; Vees Hansjorg; Miralbell Raymond

    2008-01-01

    Abstract Background To compare morphological gross tumor volumes (GTVs), defined as pre- and postoperative gadolinium enhancement on T1-weighted magnetic resonance imaging to biological tumor volumes (BTVs), defined by the uptake of 18F fluoroethyltyrosine (FET) for the radiotherapy planning of high-grade glioma, using a dedicated positron emission tomography (PET)-CT scanner equipped with three triangulation lasers for patient positioning. Methods Nineteen patients with malignant glioma were...

  8. Isodose-based methodology for minimizing the morbidity and mortality of thoracic hypofractionated radiotherapy

    International Nuclear Information System (INIS)

    Background and purpose: Help identify and define potential normal tissue dose constraints to minimize the mortality and morbidity of hypofractionated lung radiotherapy. Materials and methods: A method to generate isodose-based constraints and visually evaluate treatment plans, based on the published peer reviewed literature and the linear quadratic model, is presented. The radiobiological analysis assumes that the linear quadratic model is valid up to 28 Gy per fraction, the α/β ratio is 2 for the spinal cord and brachial plexus, 4 for pneumonitis, 4 or 10 for acute skin reactions depending on treatment length, and 3 for late complications in other normal tissues. A review of the literature was necessary to identify possible endpoints and normal tissue constraints for thoracic hypofractionated lung radiotherapy. Results: Preliminary normal tissue constraints to reduce mortality and morbidity were defined for organs at risk based upon hypofractionated lung radiotherapy publications. A modified dose nomenclature was introduced to facilitate the comparison of hypofractionated doses. Potential side effects from hypofractionated lung radiotherapy such as aortic dissection, neuropathy, and fatal organ perforation rarely seen in conventional treatments were identified. The isodose-based method for treatment plan analysis and normal tissue dose constraint simplification was illustrated. Conclusions: The radiobiological analysis based on the LQ method, biologically equivalent dose nomenclature, and isodose-based method proposed in this study simplifies normal tissue dose constraints and treatment plan evaluation. This may also be applied to extrathoracic hypofractionated radiotherapy. Prospective validation of these preliminary thoracic normal tissue dose constraints for hypofractionated lung radiotherapy is necessary.

  9. Effects of Radiotherapy in the treatment of multiple myeloma: a retrospective analysis of a Single Institution

    International Nuclear Information System (INIS)

    Palliative irradiation of osteolytic lesions is a considerable component in the treatment for patients with multiple myeloma. In this study, we analyzed the efficacy of irradiation in these patients. We retrospectively analyzed 153 patients with multiple myeloma who were admitted to our department between 1989 and 2013. According to the staging system of Durie & Salmon 116 patients were classified as stage III. 107/153 patients were treated with radiotherapy of at least one and up to 6 bony lesions at different times. In order to evaluate the effect of local radiotherapy on pain relief and bone recalcification a uni- and multivariate analysis was performed using a binary logistic regression model to correct for multiple measurements. Complete information on dose, fractionation and volume of radiotherapy was available from 81 patients treated in 136 target volumes for pain relief, and from 69 patients treated in 108 target volumes for recalcification. Total radiation doses varied between 8 Gy to 50 Gy (median dose 25 Gy in 2.5 Gy fractions, 5 times a week). Radiotherapy resulted in complete local pain relief in 31% and partial local pain relief in 54% of the patients. In the univariate analysis, higher total radiation doses (p = 0.023) and higher age (p = 0.014) at the time of radiotherapy were significantly associated with a higher likelihood of pain relief, whereas no significant association was detected for concurrent systemic treatment, type and stage of myeloma and location of bone lesions. The same variables were independent predictors for pain relief in the multivariate analysis. Recalcification was observed in 48% of irradiated bone lesions. In the uni- and multivariate analysis higher radiation doses were significantly associated (p = 0.048) with an increased likelihood of recalcification. Side effects of radiotherapy were generally mild. Higher total biological radiation doses were associated with better pain relief and recalcification in this

  10. Geographic delivery models for radiotherapy services

    International Nuclear Information System (INIS)

    The study described here was undertaken to quantify the societal cost of radiotherapy in idealized urban and rural populations and, hence, to generate a measure of impediment to access. The costs of centralized, distributed comprehensive and satellite radiotherapy delivery formats were examined by decomposing them into institutional, productivity and geographical components. Our results indicate that centralized radiotherapy imposes the greatest financial burden on the patient population in both urban and rural scenarios. The financial burden faced by patients who must travel for radiotherapy can be interpreted as one component of the overall impediment to access. With advances in remote-monitoring systems, it is possible to maintain technical quality while enhancing patient access. However, the maintenance of professional competence will remain a challenge with a distributed service-delivery format. Copyright (2002) Blackwell Science Pty Ltd

  11. The IAEA quality audits for radiotherapy

    International Nuclear Information System (INIS)

    The IAEA, jointly with the World Health Organization (WHO), for over 40 years has operated a dosimetry audit service for radiotherapy using thermoluminescent dosimeters (TLD). The service is known as the IAEA/WHO TLD postal dose audits and it is one of the oldest dosimetry services in the world. To-date, the calibration of approximately 8000 radiotherapy beams in 1700 cancer centres in 120 countries have been audited through this service. An integral part of the auditing process is resolving discrepancies in the beam calibrations that are discovered. The discrepancies are followed-up by the IAEA and local experts, and their causes are traced, understood and corrected. Significant improvements have been observed in dosimetry practices in radiotherapy centres worldwide. In its early years, the IAEA/WHO TLD postal dose audit service recorded approximately 50% audited centres had the adequate beam calibration used for cancer treatment. The provision of regular auditing programme over long time enables the IAEA to document that several radiotherapy centres have improved their abilities to accurately deliver the radiation dose. The percentage of acceptable results has reached 96% at present. However, 4% of the poor results remain uncorrected either due to a failure to respond to the IAEA/WHO efforts or due to local problems that could not be resolved without allocation of appropriate resources. Some centres work within practical limitations such as insufficient availability of qualified medical physicists or lack of adequate dosimetry equipment, which compromises quality. These inadequacies have to be addressed locally. Another dosimetry audit programme for treatment planning in external beam radiotherapy, which has been developed by the IAEA, called TPS audit, is based on a semi-anthropomorphic phantom. It assesses the radiotherapy workflow for conformal techniques, from patient data acquisition and computerized treatment planning to dose delivery. The IAEA is

  12. Worldwide quality assurance networks for radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Several national and international organizations have developed various types and levels of external audit systems for radiotherapy dosimetry, either based on on-site review visits or using mailed dosimetry systems.Three major TLD (thermoluminescence dosimetry) networks make available postal dose audits to a large number of radiotherapy centres on a regular basis. These are the IAEA/WHO (World Health Organization) TLD postal dose audit service, which operates worldwide; the European Society for Therapeutic Radiology and Oncology (ESTRO) network, known as EQUAL, which operates in the European Union; and the Radiological Physics Center (RPC) network in North America. Other external audit programmes are either associated with national and international clinical trial groups or perform national dosimetry comparisons that check radiotherapy dosimetry at various levels. The paper discusses the present status of the worldwide quality assurance networks in radiotherapy dosimetry and reviews the activities of the three main TLD networks: the IAEA/WHO, EQUAL and RPC networks. (author)

  13. Review of cranial radiotherapy-induced vasculopathy.

    Science.gov (United States)

    Murphy, Erin S; Xie, Hao; Merchant, Thomas E; Yu, Jennifer S; Chao, Samuel T; Suh, John H

    2015-05-01

    Cranial radiation can impact the cerebral vasculature in many ways, with a wide range of clinical manifestations. The incidence of these late effects including cerebrovascular accidents (CVAs), lacunar lesions, vascular occlusive disease including moyamoya syndrome, vascular malformations, and hemorrhage is not well known. This article reviews the preclinical findings regarding the pathophysiology of late radiation-induced vascular damage, and discusses the clinical incidence and risk factors for each type of vasculopathy. The pathophysiology is complex and dependent on the targeted blood vessels, and upregulation of pro-inflammatory and hypoxia-related genes. The risk factors for adult CVAs are similar to those for patients not exposed to cranial radiotherapy. For children, risks for late vascular complications include young age at radiotherapy, radiotherapy dose, NF1, tumor location, chemotherapy, and endocrine abnormalities. The incidence of late vascular complications of radiotherapy may be impacted by improved technology, therapeutic interventions, and appropriate follow up. PMID:25670390

  14. Intensity modulated radiotherapy (IMRT) in bilateral retinoblastoma

    International Nuclear Information System (INIS)

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

  15. Radiological protection and its organization in radiotherapy

    International Nuclear Information System (INIS)

    By means of a research carried out in Radiotherapy Centers in Mexico City, divided in 7 public institutions and 5 private, aspects related to the radiological safety and its organization in radiotherapy were evaluated. The population being studied was: medical and technical personnel, that works in the selected radiotherapy centers. The survey was made with 36 dichotomic variables, being obtained 90 surveys. The personnel characteristics are: 76% works for more than 3 years in radiotherapy, 93% has updated information about radiological protection, 67% knows the general radiological safety regulations, 93% knows the radiological emergency project and 95% makes use of personal dosemeter. As result of this research we found that the main problems that the radiological protection have are: lack of personnel training in radiological protection, although the 93% states to have updated information, the few number of persons that takes part in clinical meetings and professional associations. (authors). 7 refs., 3 tabs

  16. Pregnancy and radiotherapy for breast cancer

    International Nuclear Information System (INIS)

    Cancer in pregnancy is relatively uncommon but breast cancer is one of the most common malignancy occur with pregnancy. Prescribed doses of radiotherapy are significantly higher than those of diagnostic procedures. Fetal exposure and damage can occur during radiotherapy within target area. Because of those risks, radiotherapy during pregnancy is basically has to avoid. Even though, feral damage depends on fetal dose and has some threshold dose. Practically, even in stochastic effect, there are some minimal doses. A most important point is careful estimation of fetal dose before radiation. The physician has to inform the patient about risk and benefit of radiotherapy to fetus and to mother and have an ethical balance to help the mother and family to make a final decision. (author)

  17. The radiotherapy affects the cognitive processes

    International Nuclear Information System (INIS)

    Researchers from the medical center of the free university of Amsterdam report that the radiotherapy can hinder the cognitive functions of patients affected by cerebral tumors treated after a surgery. Even low dose radiation could contribute in their opinion, to the progressive cognitive decline of patients suffering of low grade gliomas, the most commune cerebral tumor. To get these conclusions, 65 patients, whom half of them received a radiotherapy, had a neurological and psychological evaluation twelve years after their treatment. Results: 53% of patients treated by radiotherapy present disorders of attention, memory, execution and speed of information treatment against 27% of these ones that received an only surgery. The researchers conclude to the necessity to take into account this risk in the choice of treatment, or even to avoid radiotherapy in this precise case. (N.C.)

  18. Implementation of patients radiation protection in radiotherapy

    International Nuclear Information System (INIS)

    Current status of quality assurance programmes in the Czech Republic is highlighted and the structure of quality audits is explained. The results of radiotherapy department auditing are given in a tabular form. It is shown that deviations from tolerable levels are mostly due to obsolete equipment and lack of health physicists at radiotherapy departments. The audits can help rectify the situation in part at least. (P.A.)

  19. Acute myocardial infarction after mediastinal radiotherapy

    International Nuclear Information System (INIS)

    Mediastinal radiotherapy can affect the heart and great vessels to different degrees. It may turn up as coronary heart disease and less frequently as acute myocardial infarction. We report the case of a patient without coronary risk factors and an antecedent of mediastinal radiotherapy for Hodgkin's lymphoma. Considerations about mediastinal radiation as a risk factor for early development of coronary heart diseases are exposed. (author)

  20. The result of radiotherapy for pituitary adenoma

    International Nuclear Information System (INIS)

    To evaluate the prognostic factors for disease-free survival and long-term results of radiotherapy for pituitary adenoma. The study involved a retrospective review of outcome in a series of 27 patients with pituitary adenoma, between 1984 and 1995 at Paik hospital. The study included 20 patients treated with surgery and postoperative radiotherapy and 7 with radiotherapy alone. The patients were followed for 12-146 months (median: 97 months). Seventeen were men and 10 were women. The numbers of functioning and non-functioning pituitary adenoma were 22 and 5 respectively and those of microadenoma and macroadenoma were 4 and 23 respectively. The radiation doses of 5040-5580cGy(median: 5040cGy) were delivered over 5-7 weeks, using 4MV LINAC. The prognostic factors were analyzed by log-rank test. For radiation therapy alone, the 5 YSR was 100% and progression free survival rate was 85.8%. The tumor was controlled in 6/7 (85.8%). For surgery and postoperative radiotherapy , the 5YSR, progression free survival rate and local control rate were 95%, 84.8%, and 89.5% respectively. The parameters of tumor size, hormone secretion, radiation dose, radiotherapy field size were evaluated in a uni- and multivariate analysis and all the factors were not statistically significant (P>0.05). Eleven of 12 (92%) with visual field defect experienced normalization or improvement, and 5 for 7 evaluable patients with hyperprolactinoma achieved normalization in 4 and decrement in 5 patients. Only 2 patients developed mild degree of panhypopituitarism. The radiotherapy appears to be effective in controlling clinical symptoms and signs resulting from pituitary adenoma. Local control rate with radiotherapy alone or with surgery and postoperative radiotherapy was comparable. There was a trend toward high recurrence rate in patients with nonfunctioning or prolactin secreting tumor and larger radiation field sizes. (author)

  1. Radiotherapy and immune reaction of oncologic patients

    International Nuclear Information System (INIS)

    Represented is a review of data accumulated in literature (1970-1976) on oppression of protection of oncologic patients and more oppression of immune reactions during radiotherapy. Underlined is the significance of studying immune homeostasis in a clinic of radiotherapy to evaluate total resistance of patients before the beginning and in the process of treatment. The prognostic significance of immunodepressive disturbances in patients with malignant tumors is elucidated

  2. Atomic and molecular data for radiotherapy

    International Nuclear Information System (INIS)

    This is the summary report of the First Research Co-ordination Meeting of the IAEA Co-ordinated Research Programme (CRP) on Atomic and Molecular Data for Radiotherapy, convened by the IAEA Nuclear Data Section in Vienna, from 30 January to 2 February 1989. The main objectives of the CRP are to generate, compile and evaluate the important atomic and molecular data relevant to radiotherapy. (author). 38 refs, 7 figs, 10 tabs

  3. Present status of radiotherapy in Venezuela

    International Nuclear Information System (INIS)

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

  4. Possibilities and limits of radiotherapy in larynx carcinoma. Moeglichkeiten und Grenzen der Radiotherapie des Larynxkarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Fietkau, R.; Sauer, R. (Erlangen-Nuernberg Univ., Erlangen (Germany). Strahlentherapeutische Klinik und Poliklinik)

    1992-01-01

    Early stage glottic carcinoma can be treated with primary radiotherapy reaching equally good results compared to primary surgery; for supraglottic carcinoma surgery offers only slight advantages over primary radiotherapy. Tumor control for recurrences is considerably improved by salvage surgery. The use of primary radiotherapy allows improved or at least preserved voice and reduced rated of acute complications and late treatment sequelae. However, treatment duration is longer and probably more expensive compared to function preservation microlaryngoscopic surgery. Which treatment approach is chosen, depends in individual patient factors and specific conditions in the clinical setting. In any case, primary radiotherapy deserves a stronger say in the early stage tumor situation. In our institution early stage supraglottic carcinoma undergo primary surgery. Advanced carcinomas (T2b and more) are rarely suited for primary radiotherapy with the exception of some very confined T3 tumors. Surgical approaches should be favoured, since they provide a detailed pathological tumor staging including R-classification, which would be lacking using primary radiotherapy. There are clear reasons to treat the lymph nodes for glottic carcinomas stage T2b and more and for all supraglottic carcinomas with radiotherapy. Specific risk factors are: tumor at the margins of the incision (R1), infiltration of the cartilage and pre-epiglottic space, paratracheal and subglottic extension more than 1 cm, perineural invasion, grade III and IV as well as emergency tracheostomy. Postoperative radiotherapy should be given to the lymph nodes for all positive neck-dissections. New therapeutic approaches are on the horizon, which may improve thee results of radiotherapy even for advanced larynx carcinomas, like hyperfractionation radiotherapy and simultaneous radio-chemotherapy combined enoral resection and postoperative radiotherapy may yield larynx preservation even for advanced stages. (orig./MG).

  5. A quality management system for radiotherapy physics

    International Nuclear Information System (INIS)

    The importance of quality in Radiotherapy Physics cannot be overemphasized and the need for having controlled, written procedures for all tasks is increasing in importance. There are a number of quality standards currently in use such as ISO 9000. In the UK, the Quality Assurance in Radiotherapy (QART) Standard has been produced based on ISO9000 and recommended for implementation in all Radiotherapy Departments. A Quality Management System has been implemented in the Radiotherapy Physics Section at the Norfolk and Norwich Hospital, England, to fulfil the QART and ISO9000 recommendations. This Poster will illustrate the system used at the Norfolk and Norwich Hospital. The system offers a standardised document format and allows the issue and re-issue of all written procedures and proforma. It has enhanced the quality and consistency of tasks, when the task is performed by varying members of staff and thereby improving the quality of the service offered from the safety and organisational perspectives. It is believed that the Quality Management System used in the Radiotherapy Physics Section at the Norfolk and Norwich Hospital would be simple to implement in the majority of Radiotherapy Physics Departments

  6. Radiotherapy of adult nodal non Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    The role of radiotherapy in the treatment of nodal non-Hodgkin's lymphoma has been modified by the introduction of efficient chemotherapy and the development of different pathological classifications. The recommended treatment of early-stage aggressive lymphomas is primarily a combination chemotherapy. The interest of adjuvant radiotherapy remains unclear and has to be established through large prospective trials. If radiation therapy has to be delivered, the historical results of exclusive radiation therapy showed that involved-fields and a dose of 35-40 Gy (daily fraction of 1.8 Gy, 5 days a week) are the optimal schedule. The interest of radiotherapy in the treatment of advanced-stage aggressive lymphoma is yet to be proven. Further studies had to stratify localized stages according to the factors of the International Prognostic Index. For easy-stage low-grade lymphoma, radiotherapy remains the standard treatment. However, the appropriate technique to use is controversial. Involved-field irradiation at a dose of 35 Gy seems to be the optimal schedule, providing a 10 year disease-free survival rate of 50 % and no major toxicity. There is no standard indication of radiotherapy in the treatment advanced-stage low-grade lymphoma. For 'new' nodal lymphoma's types, the indication of radiotherapy cannot be established (mantle-zone lymphoma, marginal zone B-cell lymphoma) or must take into account the natural history (Burkitt's lymphoma, peripheral T-cell lymphoma) and the sensibility to others therapeutic methods. (authors)

  7. [Prophylactic axillary radiotherapy for breast cancer].

    Science.gov (United States)

    Rivera, S; Louvel, G; Rivin Del Campo, E; Boros, A; Oueslati, H; Deutsch, É

    2015-06-01

    Adjuvant radiotherapy, after breast conserving surgery or mastectomy for breast cancer, improves overall survival while decreasing the risk of recurrence. However, prophylactic postoperative radiotherapy of locoregional lymph nodes for breast cancer, particularly of the axillary region, is still controversial since the benefits and the risks due to axillary irradiation have not been well defined. To begin with, when performing conformal radiotherapy, volume definition is crucial for the analysis of the risk-benefit balance of any radiation treatment. Definition and contouring of the axillary lymph node region is discussed in this work, as per the recommendations of the European Society for Radiotherapy and Oncology (ESTRO). Axillary recurrences are rare, and the recent trend leads toward less aggressive surgery with regard to the axilla. In this literature review we present the data that lead us to avoid adjuvant axillary radiotherapy in pN0, pN0i+ and pN1mi patients even without axillary clearance and to perform it in some other situations. Finally, we propose an update about the potential toxicity of adjuvant axillary irradiation, which is essential for therapeutic decision-making based on current evidence, and to guide us in the evolution of our techniques and indications of axillary radiotherapy. PMID:26044178

  8. Surgery vs. radiotherapy in localized prostate cancer. Which is best?

    International Nuclear Information System (INIS)

    Surgery and radiotherapy are currently accepted alternatives for the treatment of localized prostate cancer. In the absence of relevant randomized trials no decision regarding the superiority of any of the given approaches can be made. Up to now several cohort-based approaches indicate similar outcomes for both treatments. Based on a new population based approach, Merglen and co-workers recently concluded that surgery would offer the best chance of long-term control in terms of 10-year survival for T1–T3 prostate cancer patients. Unfortunately the strength of this trial is limited by several shortcomings. Most importantly, issues of radiation dosage have not been taken into account. In addition, several relevant parameters including Gleason score and PSA are not well balanced between the arms and the assignment to arbitrary risk groups does not reflect the real biological behaviour. Thus, the data provided do not support the strong conclusion issued by the authors. Based on the data available, surgery and radiotherapy still have to be considered as equally effective

  9. Particle radiotherapy for patients with H and N malignant tumor

    International Nuclear Information System (INIS)

    Particle beams have a characteristic called the Bragg peak, which is a peak formed at a fixed depth in the body depending on the acceleration energy. Utilizing this property, a high dose can be concentrated in the target tumor while minimizing damage to surrounding normal tissues. Proton and carbon ion beams have a higher linear energy transfer (LET) than X-rays. The relative biological effectiveness of proton and carbon ion beams compared with X-rays (=1) is estimated to be 1.1 and 3.0, respectively. Therefore, we can expect particle radiotherapy to be effective for patients with radio-resistant tumors such as malignant melanoma, adenoidcystic carcinoma and adenocarcinoma. As of the end of July 2011, there were 9 particle institutes operating in Japan; the Hyogo Ion Beam Medical Center was established in May 2001 as a leading project of the ''Hyogo Cancer Strategy''. One major characteristic is that the Center can generate both proton and carbon ion beams. Locally advanced nasal, paranasal or salivary gland cell tumors are good candidates for particle radiotherapy. Downsizing of the accelerator, price reduction of the machine, broad use of particle therapy in the field of clinical oncology, and intensity modulated particle therapy are future challenges. (author)

  10. Hypofractionated radiotherapy has the potential for second cancer reduction

    Directory of Open Access Journals (Sweden)

    Besserer Jürgen

    2010-02-01

    Full Text Available Abstract Background and Purpose A model for carcinoma and sarcoma induction was used to study the dependence of carcinogenesis after radiotherapy on fractionation. Materials and methods A cancer induction model for radiotherapy doses including fractionation was used to model carcinoma and sarcoma induction after a radiation treatment. For different fractionation schemes the dose response relationships were obtained. Tumor induction was studied as a function of dose per fraction. Results If it is assumed that the tumor is treated up to the same biologically equivalent dose it was found that large dose fractions could decrease second cancer induction. The risk decreases approximately linear with increasing fraction size and is more pronounced for sarcoma induction. Carcinoma induction decreases by around 10% per 1 Gy increase in fraction dose. Sarcoma risk is decreased by about 15% per 1 Gy increase in fractionation. It is also found that tissue which is irradiated using large dose fractions to dose levels lower than 10% of the target dose potentially develop less sarcomas when compared to tissues irradiated to all dose levels. This is not observed for carcinoma induction. Conclusions It was found that carcinoma as well as sarcoma risk decreases with increasing fractionation dose. The reduction of sarcoma risk is even more pronounced than carcinoma risk. Hypofractionation is potentially beneficial with regard to second cancer induction.

  11. Porphyria and radiotherapy: yet a constellation of risk?

    International Nuclear Information System (INIS)

    Background: little is known concerning the relation of porphyrias to radiation treatment for cancer. The recent literature does not report negative outcomes at least in single cases of breast cancer, bladder cancer or in a patient with lymphoma. Theoretically, there is a risk for radiation treatment in cases of porphyrias. Case report: two patients with porphyria are described who underwent radiotherapy for glioblastoma multiforme. Case histories, radiation treatment data and the proof of porphyria are given in detail. The patients received a concomitant radiochemotherapy with infusions of ACNU [1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-(2-chloroethyl)-3-nitrosourea] every 6 weeks. The total radiation doses at the ICRU point were 60 and 38 Gy, respectively, given in single daily fractions of 2 Gy. Results: both patients responded well as far as objective tumor regression is concerned but died early after 7 and 1.5 months following diagnosis. The first patient experienced a large brain necrosis and deterioration of her porphyria. The second patient died of cardiopulmonary insufficiency still during radiotherapy with persistent or even increased signs of porphyria. The tumor showed extensive necrosis already after 38 Gy. Conclusion: in view of annotations in the literature and this case report, caution is advised as for irradiation of brain or nervous tissues in case of porphyrias. Molecular biology data seems to support this warning to some extent. (orig.)

  12. Cancer risk following radiotherapy of cervical cancer: A preliminary report

    International Nuclear Information System (INIS)

    Women treated for cervical cancer were selected for study because (a) doses to body organs following radiotherapy can be accurately determined and vary sufficiently to permit dose-response evaluations, (b) organs remote from the cervix receive low-dose exposures in the range of current scientific interest, (c) treatment is relatively successful and many patients survive long enough to be at risk of late complications of radiotherapy, and (d) several nonexposed groups of women with cervical cancer are also available for comparison. In addition, population-based cancer registries provide an opportunity to inexpensively study large numbers of individuals over many decades. The careful procedures normally used by cancer registries to record second primary cancers facilitate the study of cancer incidence for which a wider view of radiation risk is expected than can be seen in investigations of mortality. Other special features of studies of cervical cancer patients include the ability to assess the effects of very large partial-body exposures, differences in organ sensitivities to radiation, interactions of radiation with biological factors such as age, and the duration of carcinogenic response

  13. The place radiotherapy alone with respect to surgery and radiotherapy in locally advanced vulva cancers

    International Nuclear Information System (INIS)

    The author report a study which aimed at evaluating the place or radiotherapy associated with surgery and of radiotherapy without surgery when taking into care locally advanced vulva cancers. The study is based on 46 cases. After 24 months, different aspects, such as recurrence and survival, have been assessed. It appears that there is no survival difference without recurrences between both sets. Short communication

  14. Radiotherapy for pain management of bone metastases

    International Nuclear Information System (INIS)

    Purpose: This is the first Brazilian study intended to evaluate the response of pain relief with radiotherapy in three different fractionation and the clinical differences in managing pain in patients with painful bone metastases. Methods: Prospective study of patients with painful bone metastases referred to the Radiotherapy Sector of the Hospital de Cancer de Barretos for pain-relieving radiotherapy between March and December 2010. It is known that radiotherapy seems to alter the activation of osteoclast-mediated bone resorption, relieving pain in cases of painful bone metastases. Patients were assessed in relation to the status of pain intensity before and after the initiation of radiotherapy. Either a single fraction of 8Gy, five fractions of 4Gy or ten fractions of 3Gy were given. A visual analog scale (VAS) was applied by doctors, nurses and nursing technicians to assess pain intensity at each session of radiotherapy, and follow-up at 8, 30 and 90 days from the end of treatment. Results: We evaluated 92 consecutive patients, 48 male and 44 female, with a median age of 58 years. We found that 14% of patients referred from the Palliative Care or Clinical Oncology sectors need better pharmacological analgesia due to severe pain, compared with 40.5% of patients from the other sectors (p = 0.004). We also found that the onset of pain relief to patients receiving 10 fractions of 300cGy analgesia without changing the pre-radiotherapy analgesia occurred with significance after the fifth fraction. Improvement in pain experienced within 90 days of follow-up was found in eighty percent of patients, independent of fractionated radiotherapy, site of metastases and the clinical condition of the patient. Discussion/Conclusion: The Palliative Care and Clinical Oncology sectors expressed greater concern in regards to analgesia for the patient with painful bone metastases. Radiotherapy is an effective pain-relieving treatment in different fractionation studied, even though the

  15. Radiotherapy for pain management of bone metastases

    Energy Technology Data Exchange (ETDEWEB)

    Rezende Junior, Ismar de; Mattos, Marcos Duarte de; Nakamura, Ricardo; Lemes Junior, Joaquim; Vanzelli, Talita Lozano, E-mail: rezende.med@terra.com.br [Radioterapia do Hospital de Cancer de Barretos, SP (Brazil)

    2011-07-01

    Purpose: This is the first Brazilian study intended to evaluate the response of pain relief with radiotherapy in three different fractionation and the clinical differences in managing pain in patients with painful bone metastases. Methods: Prospective study of patients with painful bone metastases referred to the Radiotherapy Sector of the Hospital de Cancer de Barretos for pain-relieving radiotherapy between March and December 2010. It is known that radiotherapy seems to alter the activation of osteoclast-mediated bone resorption, relieving pain in cases of painful bone metastases. Patients were assessed in relation to the status of pain intensity before and after the initiation of radiotherapy. Either a single fraction of 8Gy, five fractions of 4Gy or ten fractions of 3Gy were given. A visual analog scale (VAS) was applied by doctors, nurses and nursing technicians to assess pain intensity at each session of radiotherapy, and follow-up at 8, 30 and 90 days from the end of treatment. Results: We evaluated 92 consecutive patients, 48 male and 44 female, with a median age of 58 years. We found that 14% of patients referred from the Palliative Care or Clinical Oncology sectors need better pharmacological analgesia due to severe pain, compared with 40.5% of patients from the other sectors (p = 0.004). We also found that the onset of pain relief to patients receiving 10 fractions of 300cGy analgesia without changing the pre-radiotherapy analgesia occurred with significance after the fifth fraction. Improvement in pain experienced within 90 days of follow-up was found in eighty percent of patients, independent of fractionated radiotherapy, site of metastases and the clinical condition of the patient. Discussion/Conclusion: The Palliative Care and Clinical Oncology sectors expressed greater concern in regards to analgesia for the patient with painful bone metastases. Radiotherapy is an effective pain-relieving treatment in different fractionation studied, even though the

  16. European Society for Radiaton Biology - 19th annual meeting

    International Nuclear Information System (INIS)

    The proceedings contain 313 abstracts of papers. The topics covered include: biological radiation effects on lipids, hormones, fibroblasts, on bone healing, DNA repair, DNA synthesis, tumor cells, giant cell formation, on the lymphatic system, central nervous system and the hematopoietic system; determination of RBE; radioprotective agents; radiotherapy; dosimetry; radiation induced mutations; oxygen effects; radiosensitivity of tumor cells; hyperthermia and hypoxia effects on radiosensitivity; biological radiation effects on the growth of plants. (J.P.)

  17. Future development of biologically relevant dosimetry.

    Science.gov (United States)

    Palmans, H; Rabus, H; Belchior, A L; Bug, M U; Galer, S; Giesen, U; Gonon, G; Gruel, G; Hilgers, G; Moro, D; Nettelbeck, H; Pinto, M; Pola, A; Pszona, S; Schettino, G; Sharpe, P H G; Teles, P; Villagrasa, C; Wilkens, J J

    2015-01-01

    Proton and ion beams are radiotherapy modalities of increasing importance and interest. Because of the different biological dose response of these radiations as compared with high-energy photon beams, the current approach of treatment prescription is based on the product of the absorbed dose to water and a biological weighting factor, but this is found to be insufficient for providing a generic method to quantify the biological outcome of radiation. It is therefore suggested to define new dosimetric quantities that allow a transparent separation of the physical processes from the biological ones. Given the complexity of the initiation and occurrence of biological processes on various time and length scales, and given that neither microdosimetry nor nanodosimetry on their own can fully describe the biological effects as a function of the distribution of energy deposition or ionization, a multiscale approach is needed to lay the foundation for the aforementioned new physical quantities relating track structure to relative biological effectiveness in proton and ion beam therapy. This article reviews the state-of-the-art microdosimetry, nanodosimetry, track structure simulations, quantification of reactive species, reference radiobiological data, cross-section data and multiscale models of biological response in the context of realizing the new quantities. It also introduces the European metrology project, Biologically Weighted Quantities in Radiotherapy, which aims to investigate the feasibility of establishing a multiscale model as the basis of the new quantities. A tentative generic expression of how the weighting of physical quantities at different length scales could be carried out is presented. PMID:25257709

  18. Can Aidi injection alleviate the toxicity and improve the clinical efficacy of radiotherapy in lung cancer?

    Science.gov (United States)

    Xiao, Zheng; Liang, Rui; Wang, Cheng-qiong; Xu, Shaofeng; Li, Nana; He, Yuejuan; Tang, Fushan; Chen, Ling; Ma, Hu

    2016-01-01

    Abstract Background/Introduction: Aidi injection plus radiotherapy is widely used for lung cancer in China. Can Aidi injection alleviate the toxicity and improve the clinical efficacy of radiotherapy in lung cancer? Has Aidi injection the attenuation and synergistic efficacy to radiotherapy? There is lack of strong evidence to prove it. Objectives: To reveal its real attenuation and synergistic efficacy to radiotherapy and provide sufficient evidence for adjuvant chemotherapy strategies to lung cancer, we systematically evaluated all related studies. Data Sources: We collected all studies about Aidi injection plus radiotherapy for lung cancer in Medline, Embase, Web of Science, China national knowledge infrastructure database (CNKI), Chinese scientific journals full-text database (VIP), Wanfang database, China biological medicine database (CBM) (established to June 2015), and Cochrane Central Register of Controlled Trials (June 2015), evaluated their quality according to the Cochrane evaluation handbook of randomized controlled trials (5.1.0), extracted data following the PICO principles and synthesized the data by Meta analysis. Results: Sixteen randomized controlled trials (RCTs) with 1192 lung cancer patients were included, with general methodological quality in most trials. The merged relative risk (RR) values and their 95% CI of meta-analysis for objective response rate (ORR), disease control rate (DCR), and quality of life (QOL) were as follows: 1.54, (1.39,1.70), 1.10 (1.02, 1.19), and 2.13 (1.68, 2.68). The merged RR values and their 95% CI of meta-analysis for myelosuppression and neutropenia, radiation pneumonitis, and radiation esophagitis were as follows: 0.51 (0.38, 0.69), 0.53 (0.42, 0.65), 0.52 (0.41, 0.67), and 0.52 (0.40, 0.68). All were statistically significant. The possibility of publication bias was small which objectively reported the results. Conclusions: The evidence available indicates that Aidi injection plus radiotherapy can significantly

  19. Research of heavy ion radiotherapy based on formation of heterochromatin

    International Nuclear Information System (INIS)

    We studied about mechanism of heavy ion radiotherapy based on formation of heterochromatin. Role of D-NHEJ or HRR pathway in the biological effect of heavy ion irradiation is not clear. XRCC4 is a core factor of D-NHEJ pathway. For the purpose of determining the role of D-NHEJ in the effect of heavy ion irradiation, we performed survival fraction assay using HCT116 XRCC4-/- cells. Surprisingly, linear energy transfer (LET) dependency of survival fraction assay of HCT116 XRCC4-/- cells lost clearly. Preliminary data of survival fraction assay using HCT116 XRCC4-/- rescued by XRCC4 plasmid showed recovery of LET dependency. We are going to do further analysis in detail. (author)

  20. Conformational radiotherapy in the case of prostate cancer: experience gained by the Blida Oncology Radiotherapy Department, Algeria; La radiotherapie conformationnelle dans le cancer de la prostate: experience du service de radiotherapie oncologique de Blida, Algerie

    Energy Technology Data Exchange (ETDEWEB)

    Ayad, M.; Abbas, L.; Mesli, S.; Boualga, K. [Centre anti cancer, Blida (Algeria)

    2010-10-15

    Conformational radiotherapy is used as the first method for the treatment of localized prostate cancers. It preserves some life quality and allows a significant reduction of the dose applied to healthy organs, and therefore a drastic reduction of late and severe effects of irradiation. The authors report a prospective study which aims at describing therapeutic modalities and assessing preliminary results in terms of biochemical control and toxicity. They discuss the results obtained on 34 patients who have been treated between January 2008 and January 2009. In comparison with conventional therapy, they observe an absence of grade 3 and 4 side effects, and a normalization of biological criteria which indicates a good tumour response. Short communication

  1. Radiotherapy Treatment Planning for Testicular Seminoma

    Energy Technology Data Exchange (ETDEWEB)

    Wilder, Richard B., E-mail: richardbwilder@yahoo.com [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Buyyounouski, Mark K. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Efstathiou, Jason A. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Beard, Clair J. [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, MA (United States)

    2012-07-15

    Virtually all patients with Stage I testicular seminoma are cured regardless of postorchiectomy management. For patients treated with adjuvant radiotherapy, late toxicity is a major concern. However, toxicity may be limited by radiotherapy techniques that minimize radiation exposure of healthy normal tissues. This article is an evidence-based review that provides radiotherapy treatment planning recommendations for testicular seminoma. The minority of Stage I patients who choose adjuvant treatment over surveillance may be considered for (1) para-aortic irradiation to 20 Gy in 10 fractions, or (2) carboplatin chemotherapy consisting of area under the curve, AUC = 7 Multiplication-Sign 1-2 cycles. Two-dimensional radiotherapy based on bony anatomy is a simple and effective treatment for Stage IIA or IIB testicular seminoma. Centers with expertise in vascular and nodal anatomy may consider use of anteroposterior-posteroanterior fields based on three-dimensional conformal radiotherapy instead. For modified dog-leg fields delivering 20 Gy in 10 fractions, clinical studies support placement of the inferior border at the top of the acetabulum. Clinical and nodal mapping studies support placement of the superior border of all radiotherapy fields at the top of the T12 vertebral body. For Stage IIA and IIB patients, an anteroposterior-posteroanterior boost is then delivered to the adenopathy with a 2-cm margin to the block edge. The boost dose consists of 10 Gy in 5 fractions for Stage IIA and 16 Gy in 8 fractions for Stage IIB. Alternatively, bleomycin, etoposide, and cisplatin chemotherapy for 3 cycles or etoposide and cisplatin chemotherapy for 4 cycles may be delivered to Stage IIA or IIB patients (e.g., if they have a horseshoe kidney, inflammatory bowel disease, or a history of radiotherapy).

  2. Radiotherapy of adenomyosarcomas in children

    International Nuclear Information System (INIS)

    A combined treatment with surgery, radiotherapy and chemotherapy is necessary for children with adenomyosarcomas. In order to reduce the side effects of the treatment, it seems reasonable to establish a therapy plan taking into consideration the risk of recurrences. Besides the classification of stages according to the N.W.T.S., the following factors should be considered: histologic findings, manifestations of the lymph nodes, number of tumor nodes, sizes of the adenomyosarcoma, and a rupture of the adenomyosarcoma. A postoperative polychemotherapy is sufficient for children of stage I presenting favorable histological foundings. For the stages II and III, an irradiation of the tumor and the lymph outflow regions or the total abdomen with 24 Gy is recommendable in addition to chemotherapy. For stage IV, an irradiation of the lung up to 12 Gy in addition to chemotherapy has proved to be useful. A pre-operative radio- or chemotherapy is indicated especially in case of a great tumor volume and stage III and IV. (orig.)

  3. Post prostatectomy radiotherapy: our experience

    International Nuclear Information System (INIS)

    Full text: Background: Between 2000 and 2005, at Vidt Medical Center, 85 patients were treated with 3D and IMRT radiotherapy after undergoing radical prostatectomy for localized prostate adenocarcinoma. Objective: To evaluate biochemical recurrence and specific disease free survival and global survival. Materials and method: These patients were divided into two groups: those who engaged in what is called adjuvant therapy (20 patients), who after surgery had increased risk factors and / or persistence of the disease. These risk factors were positive margins, seminal vesicles involvement, capsule infiltration or persistent PSA. The other group were 65 patients referred to as rescue therapy: they were those that presented PSA increase after having undetectable levels as observed nadir after surgery, understanding > 0.2 ng / ml as a high value or palpable nodule on rectal touch with or without positive biopsy. Follow up was between 24 and 84 months, the dose delivered was between 6500 - 7000 cGy. Also evaluated the early and late toxicity, urinary and rectal, according to RTOG criteria. Conclusion: The results obtained confirm the benefits of postoperative radiation therapy for both groups of patients, showing a more favorable trend on those treated with adjuvant therapy. (authors)

  4. Radiotherapy alone in breast cancer

    International Nuclear Information System (INIS)

    This retrospective analysis was conducted on breast cancer patients treated by radiotherapy alone at The Princess Margaret Hospital and at the Institut Gustave-Roussy. These patients had either operable tumours, but were unfit for general anesthesia, or had inoperable tumors due to local contraindications to surgery. Previous results showed that a radiation dose increase of 15 Gy can decrease the relative risk of tumour or lymph node recurrence twofold. In this third report, the same data were analyzed to determine the treatment-related complication rates and to correlate these to the radiation dose levels. Overall results were analyzed on 453 patients, but detailed analyses on complications were conducted on 372 patients not developing local recurrence in the first 6 months of follow-up. Each complication was graded on a 3-level previously defined scale. Most frequent complications were skin changes of different degrees, which were usually asymptomatic. More disabling complications were arm edema, impaired shoulder mobility, rib fractures and brachial plexopathy. The incidence of disabling complications was low. The only factor significantly increasing the risk of complications was the radiation dose level to the tumour and axilla. Technical factors such as overlapping fields should also be taken into account. As the more effective control of tumour and lymph nodes obtained in patients treated with higher radiation doses is counterbalanced by an increase in the complication rate, the dose to be delivered for each patient should be carefully chosen according to individual risk factors. (author). figs

  5. Post Pelvic Radiotherapy Bony Changes

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Seung Jae [Samsung Medical Center, Seoul (Korea, Republic of)

    2009-03-15

    There has been recent interest in radiation-induced bone injury in clinical conditions, especially for pelvic insufficiency fracture (PIF). A PIF is caused by the effect of normal or physiological stress on bone with demineralization and decreased elastic resistance. Pelvic radiotherapy (RT) can also contribute to the development of a PIF. A PIF has been regarded as a rare complication with the use of megavoltage equipment. However, recent studies have reported the incidence of PIFs as 8.2{approx}20% after pelvic RT in gynecological patients, an incidence that was higher than previously believed. The importance of understanding a PIF lies in the potential for misdiagnosis as a bony metastasis. If patients complain of pelvic pain after whole-pelvis radiation therapy, the presence of a PIF must be considered in the differential diagnosis. The use of multibeam arrangements and conformal RT to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture. In addition to a PIF, osteonecrosis and avascular necrosis of the femoral head can develop after radiation therapy. Osteoradionecrosis of the pelvic bone is a clinical diagnostic challenge that must be differentiated from an osseous metastasis. A post-radiation bone sarcoma can result as a long-term sequela of pelvic irradiation for uterine cervical cancer.

  6. Radiotherapy for the vulvar cancer

    International Nuclear Information System (INIS)

    Fifteen patients who had primary vulvar cancer treated with radiotherapy as an initial treatment at Hyogo Medical Center for Adults and Hyogo Cancer Center from January 1971 to December 1990 are presented. Two patients were stage 0, one stage I, three stage II and nine stage III. Nine patients received electron irradiation with or without interstitial irradiation and intracavitary vaginal irradiation. Five patients received megavoltage X-ray irradiation using AP/PA parallel opposed fields including the pelvic nodes and perineum followed by boost irradiation of electrons, interstitial irradiation and intracavitary vaginal irradiation. The total dose delivered to the primary tumor ranged from 50 to 100 Gy (73 Gy on average). The actuarial 5-year survival rate of the patients was 43.6%. Complete regression (CR) was achieved in 60% of the patients. However, CR was not achieved in any of five patients with palpable inguinal nodes. In contrast, all the patients who had tumors of less than 2 cm in diameter achieved CR. Five of nine CR cases relapsed. First sites of failure were vagina, groin and vulvar region. Recurrence occurred more than four years after treatment in three cases. Necrosis occurred in five of nine CR cases. (author)

  7. Radiotherapy for the vulvar cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hirota, Saeko; Soejima, Toshinori; Motohara, Tomofumi (Hyogo Medical Center for Adults, Akashi (Japan)) (and others)

    1993-03-01

    Fifteen patients who had primary vulvar cancer treated with radiotherapy as an initial treatment at Hyogo Medical Center for Adults and Hyogo Cancer Center from January 1971 to December 1990 are presented. Two patients were stage 0, one stage I, three stage II and nine stage III. Nine patients received electron irradiation with or without interstitial irradiation and intracavitary vaginal irradiation. Five patients received megavoltage X-ray irradiation using AP/PA parallel opposed fields including the pelvic nodes and perineum followed by boost irradiation of electrons, interstitial irradiation and intracavitary vaginal irradiation. The total dose delivered to the primary tumor ranged from 50 to 100 Gy (73 Gy on average). The actuarial 5-year survival rate of the patients was 43.6%. Complete regression (CR) was achieved in 60% of the patients. However, CR was not achieved in any of five patients with palpable inguinal nodes. In contrast, all the patients who had tumors of less than 2 cm in diameter achieved CR. Five of nine CR cases relapsed. First sites of failure were vagina, groin and vulvar region. Recurrence occurred more than four years after treatment in three cases. Necrosis occurred in five of nine CR cases. (author).

  8. Biology Notes.

    Science.gov (United States)

    School Science Review, 1982

    1982-01-01

    Presents procedures, exercises, demonstrations, and information on a variety of biology topics including labeling systems, biological indicators of stream pollution, growth of lichens, reproductive capacity of bulbous buttercups, a straw balance to measure transpiration, interaction of fungi, osmosis, and nitrogen fixation and crop production. (DC)

  9. Results of heavy ion radiotherapy

    International Nuclear Information System (INIS)

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists

  10. A neurosurgery/stereotactic radiotherapy dedicated PACS for conformal radiotherapy

    International Nuclear Information System (INIS)

    To realise conformal cerebral stereotactic irradiations we use a Neurosurgery/stereotactic dedicated PACS between two distant hospitals. It connects the stereotactic neurosurgery planification imaging system NEUROAXIS (Sopelem-Sofretec/Ste Anne Hospital) with the dosimetric TPS ARTEMIS-3D/Dosigray (Tenon Hospital). NEUROAXIS is a computer aided stereotactic biopsies and stereo-electroencephalographies, used by surgeons in operating room. The system determines the precise location data for Talairach radiological equipment (X ray source at 5 meters from film) and the geometry of scanner and MRI stereotactical referentials. It provides a full set of features for lesion localization, geometrical computations, surgical planifications, picture archiving, stereotactic angiography, CT and MRI image processing and networking. It sends images through the French public digital network ISDN (NUMERIS/France Telecom : 2x64 Kbits/s) from Ste Anne to Tenon Hospital. Stereotactic angiographic and CT images are reformatted into the DOSIGRAY image processing environment where 3-D dose distributions, displays and DVHs are computed to determine the optimal treatment. ARTEMIS-3D/Dosigray is a TPS for stereotactic radiotherapy devised by the Tenon Hospital for clinical methodology and 3D dose calculations, optimization software development and the Dosigray company for multimodality imaging, (2D(3D)) computer graphics for dose and anatomical representation and data networking. Communication within the radiation oncology department is provided by local area ETHERNET network, linking heterogeneous systems (Vaxstations-3200; Decstation (5000(240))) by means of different protocols. The works in progress are to send back via the same network the 3-D dose matrix to Neurosurgery department NEUROAXIS system. Our PACS is used since six months to treat patients. It has permitted to improve the treatment quality in comparison with our first version TPS ARTEMIS-3D

  11. Optimal radiotherapy utilisation rate in developing countries: An IAEA study

    International Nuclear Information System (INIS)

    Optimal radiotherapy utilisation rate (RTU) is the proportion of all cancer cases that should receive radiotherapy. Optimal RTU was estimated for 9 Middle Income Countries as part of a larger IAEA project to better understand RTU and stage distribution

  12. Volumes and doses for external radiotherapy - Definitions and recommendations

    International Nuclear Information System (INIS)

    The report contains definitions of volume and dose parameters for external radiotherapy. In addition the report contains recommendations for use, documentation and minimum reporting for radiotherapy of the individual patient.(Author)

  13. Correlative study on anemia and radiotherapy effects in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Objective: To study the effect of oxygen-carrying ability of blood efficacy of radiotherapy for patients with nasopharyngeal carcinoma. Methods: Altogether 161 cases of patients with nasopharyngeal carcinoma were classified according to severity of anemia, and Hb, RBC, MCH, HCT, MCV, MCHC and RDW were tested before, during and after radiotherapy. The patients were followed-up for up to 5 years, the relationship and mechanism among anemia, radiotherapy effects and survival rate was discussed. Results: The survival rate between anemia group and non-anemia group was different significantly (P<0.05). Anemia before radiotherapy, anemia appearance or anemia deterioration during radiotherapy were sensitive factors affecting radiotherapy results. The anemia more severe, the radiotherapy worse. Conclusion: Anemia-hypohemoglobinemia leads to decrease of oxygen-carrying capacity of blood, resulting in oxygen deficiency of tumor cells and their radiotherapy resistance. Therefore this method is worthy of further studies

  14. Relationship between in vitro radiosensitivity of normal human skin fibroblasts and the occurrence of late normal tissue reactions after radiotherapy

    International Nuclear Information System (INIS)

    Late complications in normal tissues are limiting for the doses that can be administered during clinical radiotherapy. Awareness of these complications, and comprehension of the underlying biological mechanisms, is extremely important to improve cancer treatment. Fibrosis is one of the most critical injuries to radiotherapy. It varies significantly among patients despite of identical treatments. The large patient-to-patient variability of normal tissue sections to clinical radiation can possibly be accounted for by the considerable individual variation in cellular radiosensitivity of normal human fibroblasts, as shown in vitro. The purpose of the present investigation has been to analyze individual cellular radiosensitivity of normal human skin fibroblasts, as measured in a colony-forming assay, and the relationship to the occurrence of subcutaneous fibrosis after radiotherapy for breast cancer. (au) 97 refs

  15. Four and five dimensional radiotherapy with reference to prostate cancer - definitions, state of the art and further directions - an overview

    International Nuclear Information System (INIS)

    Radiotherapy (RT) always requires a compromise between tumor control and normal tissue side-effects. Technical innovation in radiation therapy (RT), such as three dimensional RT, is now established. Concerning prostate cancer (PC), it is reasonable to assume that RT of PC will increase in the future. The combination of small margins, a movable target (prostate), few fractions and high doses will probably demand dynamically positioning systems and in real time. This is called four dimensional radiotherapy (4DRT). Moreover, biological factors must be included in new treatments such as hypofractionation schedules. This new era is called five dimensional radiotherapy, 5DRT. In this paper we discuss new concepts in RT in respect to PC

  16. Chemo-radiotherapy for malignant brain tumors

    International Nuclear Information System (INIS)

    Malignant gliomas: Randomized clinical trials conducted in the USA showed that radiotherapy plus chemotherapy with nitrosoureas offered a long-term survival advantage to patients younger than 60 years old with malignant gliomas. Combination chemotherapy, such as procarbazine/CCNU/vincristine (PCV) must be tested further, and intra-arterial chemotherapy with nitrosoureas offered no survival advantage. Combination chemotherapy with PCV showed efficacy for patients with anaplastic oligodendroglioma and anaplastic oligoastrocytoma. Medulloblastoma: The addition of chemotherapy to radiotherapy improved the survival of patients with poor risk medulloblastoma, and may reduce the required craniospinal radiation dose in patients with good risk medulloblastoma. Primary CNS lymphoma (PCNSL): Combination of chemotherapy with high-dose MTX and radiotherapy improved survival of patients with PCNSL; however, the neurotoxicity produced by this treatment modality is a serious problem in older patients. Intracranial germ cell tumors: The addition of chemotherapy to radiotherapy may produce long term survival with good quality of life in patients with germinoma. Neoadjuvant therapy consisting of chemotherapy and radiotherapy followed by complete surgical excision improved survival of patients with intracranial nongerminomatous germ cell tumors. (author)

  17. Image-guided and adaptive radiotherapy

    International Nuclear Information System (INIS)

    Image-guided radiotherapy (IGRT) aims to take into account anatomical variations occurring during irradiation by visualization of anatomical structures. It may consist of a rigid registration of the tumour by moving the patient, in case of prostatic irradiation for example. IGRT associated with intensity-modulated radiotherapy (IMRT) is strongly recommended when high-dose is delivered in the prostate, where it seems to reduce rectal and bladder toxicity. In case of significant anatomical deformations, as in head and neck tumours (tumour shrinking and decrease in volume of the salivary glands), re-planning appears to be necessary, corresponding to the adaptive radiotherapy. This should ideally be 'monitored' and possibly triggered based on a calculation of cumulative dose, session after session, compared to the initial planning dose, corresponding to the concept of dose-guided adaptive radiotherapy. The creation of 'planning libraries' based on predictable organ positions (as in cervical cancer) is another way of adaptive radiotherapy. All of these strategies still appear very complex and expensive and therefore require stringent validation before being routinely applied. (authors)

  18. Chemo-radiotherapy for malignant brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kochi, Masato; Ushio, Yukitaka [Kumamoto Univ. (Japan). School of Medicine

    2002-05-01

    Malignant gliomas: Randomized clinical trials conducted in the USA showed that radiotherapy plus chemotherapy with nitrosoureas offered a long-term survival advantage to patients younger than 60 years old with malignant gliomas. Combination chemotherapy, such as procarbazine/CCNU/vincristine (PCV) must be tested further, and intra-arterial chemotherapy with nitrosoureas offered no survival advantage. Combination chemotherapy with PCV showed efficacy for patients with anaplastic oligodendroglioma and anaplastic oligoastrocytoma. Medulloblastoma: The addition of chemotherapy to radiotherapy improved the survival of patients with poor risk medulloblastoma, and may reduce the required craniospinal radiation dose in patients with good risk medulloblastoma. Primary CNS lymphoma (PCNSL): Combination of chemotherapy with high-dose MTX and radiotherapy improved survival of patients with PCNSL; however, the neurotoxicity produced by this treatment modality is a serious problem in older patients. Intracranial germ cell tumors: The addition of chemotherapy to radiotherapy may produce long term survival with good quality of life in patients with germinoma. Neoadjuvant therapy consisting of chemotherapy and radiotherapy followed by complete surgical excision improved survival of patients with intracranial nongerminomatous germ cell tumors. (author)

  19. Long-Term Breast Cancer Patient Outcomes After Adjuvant Radiotherapy Using Intensity-Modulated Radiotherapy or Conventional Tangential Radiotherapy

    OpenAIRE

    Yang, Jen-Fu; Lee, Meei-Shyuan; Lin, Chun-Shu; Chao, Hsing-Lung; Chen, Chang-Ming; Lo, Cheng-Hsiang; Fan, Chao-Yueh; Tsao, Chih-Cheng; Huang, Wen-Yen

    2016-01-01

    Abstract The aim of the article is to analyze breast cancer patient clinical outcomes after long-term follow-up using intensity-modulated radiotherapy (IMRT) or conventional tangential radiotherapy (cRT). We retrospectively reviewed patients with stage 0–III breast cancer who received breast conserving therapy between April 2004 and December 2007. Of the 234 patients, 103 (44%) were treated with IMRT and 131 (56%) were treated with cRT. A total prescription dose of 45 to 50 Gy (1.8–2 Gy per f...

  20. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  1. Minimal requirements for quality controls in radiotherapy with external beams

    International Nuclear Information System (INIS)

    Physical dosimetric guidelines have been developed by the Italian National Institute of Health study group on quality assurance in radiotherapy to define protocols for quality controls in external beam radiotherapy. While the document does not determine strict rules or firm recommendations, it suggests minimal requirements for quality controls necessary to guarantee an adequate degree of accuracy in external beam radiotherapy

  2. PET/CT Based Dose Planning in Radiotherapy

    DEFF Research Database (Denmark)

    Berthelsen, Anne Kiil; Jakobsen, Annika Loft; Sapru, Wendy;

    2011-01-01

    radiotherapy planning with PET/CT prior to the treatment. The PET/CT, including the radiotherapy planning process as well as the radiotherapy process, is outlined in detail. The demanding collaboration between mould technicians, nuclear medicine physicians and technologists, radiologists and radiology...

  3. Genetic indicators of radiotherapy normal tissue response

    International Nuclear Information System (INIS)

    Full text: The aims of this study are to identify a genetic signature for adverse normal tissue damage from clinical radiotherapy (RT) in breast cancer patients, and to characterize the differentially-regulated genes involved. We have chosen to use skin expression profiling for four main reasons; (1) skin is the tissue that expresses the damage and so is directly relevant to the investigation, (2) skin biopsies can be snap frozen to preserve and maintain the in vivo expression profile of the patient, (3) skin punch biopsies are minimally invasive which equates to a high participation rate from RT patients (4) radiosensitivity testing and similar assays of cultured cells have only a low correlation with clinical adverse reaction. We expect our molecular profiling approach will give insight into the inherent genetic status of the patient that has not been demonstrated in cellular assays. We have begun collecting and processing skin punch biopsies from unirradiated sites from informed, consenting patients with adverse (severe acute or late) reaction to the skin or subcutaneous tissue following a standard course of RT, and normal controls. We have profiled biopsies from 7 adverse normal tissue reaction patients and 4 controls. Analyses of this data has identified 202 differentially expressed genes (p<0.01) and a class prediction algorithm correctly identified as adverse reaction or normal reaction 6/7 (86%) of our test samples that it could predict. We plan to focus on the function of some of these genes to determine their biological and clinical relevance. This will include detailed analysis of several of the gene products in an effort to address why these genes are associated with clinical reaction and what signaling pathways are involved. We plan to expand our sample number to 50 severe normal tissue late reaction (RTOG Grade 3 or 4), 50 severe acute normal tissue reaction and 50 no late or acute reaction to RT (RTOG 0) patients. An expected outcome is to fabricate

  4. Concepts of radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Full text: Radiotherapy treatment planning (RTP) relies heavily on medical imaging. Until recently, the most important planning tool was the treatment simulator. The kilovoltage radiographic capabilities in a treatment simulator enabled the boundaries of treatment fields to be visualized with respect to bony anatomic landmarks. Perhaps the most important advance in treatment planning in recent years is the ability to visualize the passage of the beams with respect to a more accurate geometrical representation of the tumor and other soft tissue structures. This 'virtual simulation' uses a computer-based representation of a patient to determine the extent of the disease and the location of radiation sensitive normal tissue. Computer tomographic (CT) imaging produces a high-resolution three-dimensional representation of anatomy that can be correlated with other image sets such as magnetic resonance images (MRI) of function. Positron emission tomographic (PET) imaging is beginning to be used to determine tumor proliferation and the presence of distant disease. It is likely that accurate RTP in conjunction with CT simulators will eliminate traditional treatment simulators in the future. Traditionally, patient dose calculation algorithms have been based on correcting measured dose in water phantoms to take into account beam modifiers, patient surface contours and internal tissue inhomogeneities. Recently, model-based algorithms have been computing the dose directly in the patient representation using the CT to obtain a voxel-by-voxel density map. The convolution/superposition method, which uses a Monte Carlo-derived transport kernel, is the current state-of-the-art algorithm for dose computation. Soon direct Monte Carlo simulation will be used in model-based dose computation. Model-based dose computations enable a simpler monitor unit calculation formulation. The other major breakthrough in RTP is computer-based optimization. The goals of the treatment are specified as

  5. Radiotherapy evolution in Spain (1896-1996)

    International Nuclear Information System (INIS)

    We show radiotherapy evolution in Spain, from the introduction of the Roentgenology till the consolidation of the radiation therapy. We analyze the development of the roentgenology and the contribution of the dermatologist in it. We should emphasize the importance of the V International Congress of Electrology and Medical Radiology wich took place in December of 1910 in Barcelona in the development of the deep radiotherapy in the treatment of gynecological neoplasms. The sanitary struggle campaigns cancer influenced a lot the development of Spanish radiotherapy. the development of the Cancer's Pavilion of the ''Hospital de la Santa Creu i Sant Pau'' was the most important radiotherapic event in the previous period to the Spanish civil war. After the late introduction of cobaltotherapy in Spain, the birth of the ''Asociacion Espanola de Radioterapia y Oncologia (AERO) helped to consolidate the speciality. (Author) 36 refs

  6. Operations experience at the Bevalac radiotherapy facility

    International Nuclear Information System (INIS)

    During the first years of Bevalac operation the biomedical effort concentrated on radiobiology work, laying the foundation for patient radiotherapy. A dedicated radiotherapy area was created in 1978, and in 1979 full-scale patient treatment was begun. As of now over 500 treatments with carbon, neon and argon beams have been delivered to about 50 patients, some as boosts from other modalities and some as complete heavy ion treatments. Up to 12 patients per day have been treated in this facility. Continuing efforts in refining techniques and operating procedures are increasing efficiency and accuracy of treatments, and are contributing to the alleviation of scheduling difficulties caused by the unique requirements of radiotherapy with human patients

  7. Radiation caries - an evil eye of radiotherapy

    International Nuclear Information System (INIS)

    Although radiotherapy plays an important role in the management of patients with head and neck cancer, it is also associated with several undesired side effects such as radiation caries which is a common, yet serious, complication. The radiotherapy field of exposure frequently includes the salivary glands, oral mucosa, and jaws, thus, leading to various side effects including hyposalivation, mucositis, and taste loss. Irradiated patients are also at increased risk for the development of a rapid, rampant carious process known as radiation caries. Lesions tend to develop four weeks after completion of radiotherapy and affect atypical areas of teeth, such as the lingual surface, incisal edges, and cusp tips. The aim of this paper is to review the clinical features, prevention and management of radiation caries. (author)

  8. Radiotherapy care experience: an anthropological study

    International Nuclear Information System (INIS)

    An anthropological study has been carried out in order to evaluate the need expressed by patients undergoing radiotherapy treatment. The study was mostly qualitative and based on the radiotherapy experiences of 13 women with breast cancer and six men with head and neck cancer. A 24-year-old female anthropologist spent one year in the department of radiotherapy at the Bergonie Institute in Bordeaux. She collected data on patients' needs through the observation of their experience of treatment and personal interviews. These were put in context, analyzed both by qualitative and quantitative methods. The results pointed out the need for more information on the different steps of treatment and the patient's need 'for a smile'front the medical team; in other words, emphatic support. (author)

  9. Quality control guarantees the safety of radiotherapy

    International Nuclear Information System (INIS)

    While radiotherapy equipment has seen some decisive improvements in the last few decades, the technology has also become more complicated. The advanced equipment produces increasingly good treatment results, but the condition of the equipment must be controlled efficiently so as to eliminate any defects that might jeopardise patient safety. The quality assurance measures that are taken to show that certain equipment functions as required are known as quality control. The advanced equipment and stricter requirements set for the precision of radiotherapy have meant that more attention must be paid to quality control. The present radiation legislation stipulates that radiotherapy equipment must undergo regular quality control. The implementation of the quality control is supervised by the Finnish Centre for Radiation and Nuclear Safety (STUK). Hospitals carry out quality control in accordance with a programme approved by STUK, and STUK inspectors periodically visit hospitals to check the results of quality control. (orig.)

  10. Track structure modelling for ion radiotherapy

    CERN Document Server

    Korcyl, Marta

    2014-01-01

    In its broadest terms, doctoral dissertation entitled "Track structure modelling for ion radiotherapy" is part of the supporting research background in the development of the ambitious proton radiotherapy project currently under way at the Institute of Nuclear Physics PAN in Krak\\'ow. Another broad motivation was the desire to become directly involved in research on a topical and challenging subject of possibly developing a therapy planning system for carbon beam radiotherapy, based in its radiobiological part on the Track Structure model developed by prof. Robert Katz over 50 years ago. Thus, the general aim of this work was, firstly, to recapitulate the Track Structure model and to propose an updated and complete formulation of this model by incorporating advances made by several authors who had contributed to its development in the past. Secondly, the updated and amended (if necessary) formulation of the model was presented in a form applicable for use in computer codes which would constitute the "radiobio...

  11. External radiotherapy in a pleural mesothelioma tumor

    International Nuclear Information System (INIS)

    Pleural mesothelioma is an uncommon tumor compared with other thoracic malignancies and a 80% of the cases have asbestos exposure. From 1983 to 1992 we have examined patients suffering from malignant pleural mesothelioma treated with external radiotherapy. We treated 11 patients of which 9 were males and 2 were females. The most frequent symptom was the chest pain and all these patients underwent a torascoscopy followed by a pleasured. Of the 11 cases: 10 were malignant epithelial mesothelioma and 1 was a mixed pleural case. Afterwards, they were treated with external radiotherapy between 30 and 55 Gy, with few complications. At the moment, 5 patients are still alive and there is a survival rate of 50% at 24 and 60 months and of 25% at 120 months. We think that external radiotherapy is a good palliative treatment with few complications. (Author) 28 refs

  12. Radiotherapy: what are the patients' needs

    International Nuclear Information System (INIS)

    Although there is a substantial body of research into the impact of cancer therapies such as surgery and chemotherapy, little is known about the experiences of cancer patients receiving radiotherapy. Serial interviews with 39 patients undergoing radical radiotherapy to the oral cavity revealed that misunderstandings and groundless fears about this form of treatment were widespread. A majority were unprepared for the severity and duration of their side-effects. These results suggest that written information for patients about radiotherapy and its side-effects should be made available routinely. There is also scope for nutritional support. Finally, as a supplement to out-patient attendance, informal contact with the hospital in the immediate post-treatment phase would provide invaluable reassurance to patients. (author)

  13. Radiotherapy for Oral Cavity Cancer

    International Nuclear Information System (INIS)

    Eighty five patients of oral cavity cancer, treated with radiation at the Department of Therapeutic Radiology, Korea Cancer Center Hospital, during the period from March 1985 to September 1990 were analyzed retrospectively. Among 85 patients, 37 patients were treated with radiation only and 48 patients were treated with radiation following surgery And 70 patients received external irradiation only by 60Co with or without electron, the others were 7 patients for external irradiation plus interstitial implantation and 8 patients for external irradiation plus oral cone electron therapy. Primary sites were mobile tongue for 40 patients, mouth floor for 17 patients, palate for 12 patients, gingiva including retromolar trigone for 10 patients, buccal mucosa for 5 patients, and lip for 1 patient. According to pathologic classification, squamous cell carcinoma was the most common (77 patients). According to AJC TNM stage, stage I + II were 28 patients and stage III + IV were 57 patients. Acturial overall survival rate at 3 years was 43.9%, 3 year survival rates were 60.9% for stage I + II, and 23.1% for stage III + IV, respectively. As a prognostic factor, primary T stage was a significant factor (p<0.01). The others, age, location, lymph node metastasis, surgery, radiation dose, and cell differentiation were not statistically significant. Among those factors, radiation plus surgery was more effective than radiation only in T3 + T4 or in any N stage although it was not statistically sufficient(p<0.1). From those results, it was conclusive that definitive radiotherapy was more effective than surgery especially in the view of pertaining of anatomical integrity and function in early stage, and radiation plus surgery was considered to be better therapeutic tool in advanced stage

  14. Usefulness of a guide book for patients to self-help during radiotherapy for anxiety before radiotherapy

    International Nuclear Information System (INIS)

    From May through August 1993, 'a guide book for patients to self-help during radiotherapy' prepared at our department was given 80 patients before radiotherapy and the usefulness of this book for understanding of radiotherapy and reduction of anxiety for radiotherapy was investigated. In 83% of patients could read it through, and in 67% of these patients anxiety for treatment reduced. It is necessary that medical staffs make it clear more often, to let them understand this book more correctly. (author)

  15. Radiotherapy in the management of Graves` ophthalmopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Koh-ichi; Hareyama, Masato; Oouchi, Atsushi; Shidou, Mitsuo; Nagakura, Hisayasu; Morita, Kazuo; Osanai, Hajime; Ohtsuka, Kenji; Hinoda, Yuji [Sapporo Medical Univ. (Japan). School of Medicine

    1998-06-01

    To report the results of radiotherapy for patients with failure, adverse reactions or relative contraindications to the use of steroids or immunosuppressants, by using newly developed quantitative indexes. Fourteen female and six male patients with Graves` ophthalmopathy were treated with radiotherapy between 1989 and 1996. Prior to radiotherapy, eight patients received treatment with prednisone, four received immunosuppressants and four received a combination of both. Four patients with contraindications to steroids were initially managed with radiotherapy. Most of the patients received a dose of 24-28 Gy in 2 Gy fractions. We used the newly developed motility limitation index to assess extraocular motility. Treatment was well tolerated. There have been no late complications. All 12 patients with soft tissue signs such as edema, irritation, tearing and pain were improved. Proptosis did not improve or improved only slightly, 3 mm at best. However, proptosis in all but two has been stabilized and has not deteriorated in the follow-up period. Most of the patients have experienced an improvement of eye-muscle motility. Extraocular muscles that work for elevation were impaired more severely than the other muscles and this tended to remain. Of the 16 patients using steroids before or when radiotherapy was initiated, 15 were tapered off and only one patient required additional steroids, thus sparing the majority from steroid adverse reactions. Radiotherapy was effective in preventing exacerbations of active inflammatory ophthalmopathy in patients with Graves` disease with minimal morbidity and thus eliminated the adverse reactions associated with protracted corticosteroid use. The newly developed motility limitation index was useful in detecting delicate changes in motility of individual extraocular muscles. (author)

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

    International Nuclear Information System (INIS)

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

  17. Second Study of Hyper-Fractionated Radiotherapy

    Directory of Open Access Journals (Sweden)

    R. Jacob

    1999-01-01

    Full Text Available Purpose and Method. Hyper-fractionated radiotherapy for treatment of soft tissue sarcomas is designed to deliver a higher total dose of radiation without an increase in late normal tissue damage. In a previous study at the Royal Marsden Hospital, a total dose of 75 Gy using twice daily 1.25 Gy fractions resulted in a higher incidence of late damage than conventional radiotherapy using 2 Gy daily fractions treating to a total of 60 Gy. The current trial therefore used a lower dose per fraction of 1.2 Gy and lower total dose of 72 Gy, with 60 fractions given over a period of 6 weeks.

  18. Concomitant boost radiotherapy in oropharynx carcinomas

    OpenAIRE

    Bieri, Sabine; Allal, Abdelkarim Said; Dulguerov, Pavel; Lehmann, Willy; Kurtz, John

    1998-01-01

    Fifty-five patients with resectable and unresectable oropharynx carcinomas were treated with concomitant boost radiotherapy. Forty-two of the patients (76%) had stages III-IV disease. Although none of the patients had undergone major surgery to the primary tumor, 11 had neck dissections prior to radiotherapy, and 19 (35%) received chemotherapy. The planned total tumor dose was 69.9 Gy, delivered over 5.5 weeks. During the last 3.5 weeks, a boost to the initial gross disease was delivered in 1...

  19. Radiotherapy-induced pemphigus: a case report

    International Nuclear Information System (INIS)

    A 61-year-old male patient suffering from squamous cell carcinoma of the lower lip developed pemphigus vulgaris two months after exposure to radiotherapy. Skin lesions were initially localised to the face and neck and later extended over other skin areas. The eruption are improved with gluco-steroid therapy, which were stopped after six months. Pemphigus induced by radiotherapy is rare, latency before the onset of the vesiculo-bullous eruption is variable. Clinical, histological and immunological characteristics are similar to those of other types of pemphigus. (author)

  20. Effects of radiotherapy on central venous ports

    International Nuclear Information System (INIS)

    During radiotherapy of patients with implant able central venous ports we are often afraid of complications resulting from ports damage on the one hand and their interaction with surrounding tissues on the other hand. In experimental conditions venous ports were exposed to radiation. It was found that radiation reflected from a port is negligible and should not put patients at risk. Radiotherapy does not cause any changes within a port chamber, however it substantially affects elasticity of a polyurethane port catheter and to a minimal extent affects silicone catheter. (authors)

  1. Fatigue and radiotherapy. A literature review

    International Nuclear Information System (INIS)

    Fatigue is a common complaint for the cancer patient during and after radiotherapy, according to the published studies. Fatigue is a subjective symptom mostly underestimated by oncologists and other care givers. Etiology is complex, poorly understood in spite of obvious causes like insomnia, nausea, pain, depression, psychological distress, anemia, hypothyroidism, menopause disturbances, treatment adverse effects. Fatigue presents multi-factorial and multidimensional aspects. To evaluate it, many tools can be used as single-item, unidimensional and multidimensional instruments. Practically, the open discussion with the patient throughout radiotherapy is essential to define it. Taking charge fatigue requires its acknowledgement by radiotherapist, treatment of associated symptoms with a multidisciplinary approach. (authors)

  2. Infantile hepatic hemangioendothelioma treated by radiotherapy

    International Nuclear Information System (INIS)

    Infantile hepatic hemangioendothelioma is a rare tumor of infancy, sometimes associated with cutaneous hemangiomatosis. It is clinically evident within the first six months after birth and can be life threatening because of heart failure, intraperitoneal hemorrhage or thrombocytopenia. In less severe forms spontaneous regression has been described. Current treatment may be surgical ligation of the hepatic artery, or pharmacological therapy with corticosteroids or radiotherapy. A 4-month infant is described, admitted with acute heart failure and huge hepatomegaly. Since a surgical approach was not possible and corticosteroid therapy failed to achieve the expected effect, radiotherapy was given with excellent results. (orig.)

  3. Care of patients undergoing external radiotherapy

    International Nuclear Information System (INIS)

    The anxiety and associated depression suffered by most patients undergoing radiotherapy is discussed and the possibilities open to the nurse to encourage and reassure patients thus facilitating physical care are considered. The general symptoms of anorexia, nausea, tiredness, skin problems, alopecia, bonemarrow depresssion and rapid tumour destruction are described and nursing care prescribed. The side-effects which may occur following radiation of the brain, head and neck region, eyes, oesophagus, lung, abdomen, pelvis, bones, skin, spine, and spinal cord are considered from the nursing standpoint. The specialised subject of radiotherapy in children is discussed briefly. (U.K.)

  4. Some dosimetry problems in negative pion radiotherapy

    CERN Document Server

    Baarli, Johan

    1973-01-01

    Momentum beams of negative pions are considered for radiotherapy. It is shown that the measurement of dose in this respect presents problems which are different from those encountered when using the more usual type of radiation. This difference arises principally from the nuclear interaction processes produced when the negative pion comes to rest. These processes, which are superimposed on the Bragg peak of the beam, produce a complex mixture of charged particles together with a beam contamination of muons and electrons. Some experimental studies of depth dose distributions, dose estimates, and other parameters to be considered for radiotherapy of cancer with beams of negative pions are discussed.

  5. Quantum Biology

    CERN Document Server

    Sergi, Alessandro

    2009-01-01

    A critical assessment of the recent developments of molecular biology is presented. The thesis that they do not lead to a conceptual understanding of life and biological systems is defended. Maturana and Varela's concept of autopoiesis is briefly sketched and its logical circularity avoided by postulating the existence of underlying {\\it living processes}, entailing amplification from the microscopic to the macroscopic scale, with increasing complexity in the passage from one scale to the other. Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces, is criticized. It is suggested that the correct interpretation of quantum dispersion forces (van der Waals, hydrogen bonding, and so on) as quantum coherence effects hints at the necessity of including long-ranged forces (or mechanisms for them) in condensed matter theories of biological processes. Some quantum effects in biology are reviewed and quantum mechanics is acknowledge...

  6. Radiation biology: a century of hopes and disappointments

    International Nuclear Information System (INIS)

    In the history of science, radiation biology will rank perhaps as the most popular subject to have attracted researchers from many disciplines of basic as well as applied sciences. Apart from the excitement arising in clinics relating to radiation treatment of cancers the tragedies in Hiroshima and Nagasaki brought numerous scientists together to investigate the harmful biological effects of ionizing radiation. It is then radiation biology picked up a great momentum. It started developing in two different directions what may be called basic radiation biology and radiation biology applied to radiotherapy of cancer. While great strides were being made in basic radiation biology trying to understand the biological effects of radiation and mechanisms thereof, clinical aspect remained confined mainly to the medical fraternity where empiricalism became the rule

  7. Radiotherapy applied to tumours of the intracranial central nervous systems in the dog

    International Nuclear Information System (INIS)

    As domestic animals such as dogs are living older because of a better life quality and better cares, they may more frequently develop tumours in their intracranial central nervous system. In this research thesis, the author addresses this specific topic. He first recalls fundamental physical and biological aspects for the understanding of radiotherapy action mechanisms, and the modalities of such a treatment. He addresses the general study of intracranial central nervous system tumours in dogs: brief recall on anatomic and histological aspects, presentation of their classification and their prevalence, and precise descriptions of their characteristics. In the third part, the author reports clinical and para-clinical data which allow the diagnosis of an intracranial nervous tissue tumour. The last part presents different available therapeutic modalities, more particularly addresses the interest of radiotherapy in neuro-oncology, and compares published results

  8. Pre-clinical research in small animals using radiotherapy technology. A bidirectional translational approach

    International Nuclear Information System (INIS)

    For translational cancer research, pre-clinical in-vivo studies using small animals have become indispensable in bridging the gap between in-vitro cell experiments and clinical implementation. When setting up such small animal experiments, various biological, technical and methodical aspects have to be considered. In this work we present a comprehensive topical review based on relevant publications on irradiation techniques used for pre-clinical cancer research in mice and rats. Clinical radiotherapy treatment devices for the application of external beam radiotherapy and brachytherapy as well as dedicated research irradiation devices are feasible for small animal irradiation depending on the animal model and the experimental goals. In this work, appropriate solutions for the technological transfer of human radiation oncology to small animal radiation research are summarised. Additionally, important information concerning the experimental design is provided such that reliable and clinically relevant results can be attained.

  9. Heterogeneity correction in the construction of optimized planning in radiotherapy using linear programming

    Directory of Open Access Journals (Sweden)

    Rodrigo Sartorelo Salemi Viana

    2011-12-01

    Full Text Available A radiotherapy planning is considered optimal when all the parameters involved, physical or biological, have been investigated and appropriate for each patient. In this type of planning, the major concern is with the tumor irradiation with the minimum possible damage to healthy tissues of the irradiated region, especially the organs at risk. The optimal planning for radiotherapy can be aided by Linear Programming and there is a wide literature addressing this subject. However, most published mathematical formulations do not contemplate a scenario in terms of practical applications, because they do not incorporate the heterogeneous composition of the irradiated tissue. This paper presents a methodology for heterogeneity correction in the composition of different types of irradiated tissues based on proportions among their different linear attenuation coefficient.

  10. Post-radiotherapy locoregional recurrence of hyalinizing clear cell carcinoma of palate

    Directory of Open Access Journals (Sweden)

    Sonia Gon

    2013-01-01

    Full Text Available Clear cell carcinoma of the salivary glands is a rare tumor that represents less than 1% of all salivary tumors and is a new disease that is only recognized in recent years. It is rare and the standard treatment is still under investigation. This tumor often follows an indolent course and treatment includes wide surgical excision with or without adjuvant radiotherapy. Recurrence of the hyalinizing clear cell carcinoma (HCCC after complete surgical resection is uncommonly documented. We hereby report a case of post-radiotherapy locoregional recurrence of HCCC of the palate and recommend further clinicopathological study and long-term follow-up to document the biological behavior of this entity along with highlighting the role of special stains and immunohistochemistry in its diagnosis.

  11. Water versus DNA: new insights into proton track-structure modelling in radiobiology and radiotherapy

    Science.gov (United States)

    Champion, C.; Quinto, M. A.; Monti, J. M.; Galassi, M. E.; Weck, P. F.; Fojón, O. A.; Hanssen, J.; Rivarola, R. D.

    2015-10-01

    Water is a common surrogate of DNA for modelling the charged particle-induced ionizing processes in living tissue exposed to radiations. The present study aims at scrutinizing the validity of this approximation and then revealing new insights into proton-induced energy transfers by a comparative analysis between water and realistic biological medium. In this context, a self-consistent quantum mechanical modelling of the ionization and electron capture processes is reported within the continuum distorted wave-eikonal initial state framework for both isolated water molecules and DNA components impacted by proton beams. Their respective probability of occurrence—expressed in terms of total cross sections—as well as their energetic signature (potential and kinetic) are assessed in order to clearly emphasize the differences existing between realistic building blocks of living matter and the controverted water-medium surrogate. Consequences in radiobiology and radiotherapy will be discussed in particular in view of treatment planning refinement aiming at better radiotherapy strategies.

  12. Biological modelling of the radiation dose escalation effect of regional hyperthermia in cervical cancer

    International Nuclear Information System (INIS)

    Locoregional hyperthermia combined with radiotherapy significantly improves locoregional control and overall survival for cervical tumors compared to radiotherapy alone. In this study biological modelling is applied to quantify the effect of radiosensitization for three cervical cancer patients to evaluate the improvement in equivalent dose for the combination treatment with radiotherapy and hyperthermia. The Linear-Quadratic (LQ) model extended with temperature-dependent LQ-parameters α and β was used to model radiosensitization by hyperthermia and to calculate the conventional radiation dose that is equivalent in biological effect to the combined radiotherapy and hyperthermia treatment. External beam radiotherapy planning was performed based on a prescription dose of 46Gy in 23 fractions of 2Gy. Hyperthermia treatment using the AMC-4 system was simulated based on the actual optimized system settings used during treatment. The simulated hyperthermia treatments for the 3 patients yielded a T50 of 40.1 °C, 40.5 °C, 41.1 °C and a T90 of 39.2 °C, 39.7 °C, 40.4 °C, respectively. The combined radiotherapy and hyperthermia treatment resulted in a D95 of 52.5Gy, 55.5Gy, 56.9Gy in the GTV, a dose escalation of 7.3–11.9Gy compared to radiotherapy alone (D95 = 45.0–45.5Gy). This study applied biological modelling to evaluate radiosensitization by hyperthermia as a radiation-dose escalation for cervical cancer patients. This model is very useful to compare the effectiveness of different treatment schedules for combined radiotherapy and hyperthermia treatments and to guide the design of clinical studies on dose escalation using hyperthermia in a multi-modality setting

  13. Radiotherapy in the management of early breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei [Westmead Breast Cancer Institute, Westmead Hospital, Westmead, New South Wales (Australia); Department of Radiation Oncology, Westmead Hospital, New South Wales (Australia)

    2013-03-15

    Radiotherapy is an indispensible part of the management of all stages of breast cancer. In this article, the common indications for radiotherapy in the management of early breast cancer (stages 0, I, and II) are reviewed, including whole-breast radiotherapy as part of breast-conserving treatment for early invasive breast cancer and pre-invasive disease of ductal carcinoma in situ, post-mastectomy radiotherapy, locoregional radiotherapy, and partial breast irradiation. Key clinical studies that underpin our current practice are discussed briefly.

  14. Advancements in radiotherapy for lung cancer in China

    Institute of Scientific and Technical Information of China (English)

    Lujun Zhao; Luhua Wang

    2015-01-01

    Lung cancer is the leading cause of death due to cancer in China. In recent years, great progress has been made in radiotherapy for lung cancer patients in China. The main advance-ments include the fol owing aspects:(1) stereotactic ablative radiotherapy for early stage non-smal cel lung cancer (NSCLC), (2) post-operative radiotherapy for NSCLC, (3) combined chemotherapy and radiotherapy for local y advanced NSCLC, (4) improved radiotherapy for advanced NSCLC, and 5) prediction of radiation-induced lung toxicity.

  15. The significance and impact of dosimetry audits in radiotherapy

    International Nuclear Information System (INIS)

    Overall, dosimetry audit has improved consistency in radiotherapy results and outcomes for patients and provided confidence to clinicians in the dosimetry supporting their practice. Its importance and impact is clearly recognised and its encouragement of and links to other wider radiotherapy audit has been significant. As it is estimated that a large number of the existing radiotherapy facilities world-wide have not yet participated in some level of independent external dose quality audit, the breadth of uptake of audit is to be encouraged. As the complexity of radiotherapy develops, the scope of what can be included in dosimetry and wider radiotherapy quality audits also needs to continue to increase

  16. The Significance and Impact of Dosimetry Audits in Radiotherapy

    International Nuclear Information System (INIS)

    Overall, dosimetry audit has improved consistency in radiotherapy results and outcomes for patients and provided confidence to clinicians in the dosimetry supporting their practice. Its importance and impact is clearly recognised and its encouragement of and links to other wider radiotherapy audit has been significant. As it is estimated that a large number of the existing radiotherapy facilities world-wide have not yet participated in some level of independent external dose quality audit, the breadth of uptake of audit is to be encouraged. As the complexity of radiotherapy develops, the scope of what can be included in dosimetry and wider radiotherapy quality audits also needs to continue to increase

  17. A prospective study of urinary tract infection during pelvic radiotherapy

    International Nuclear Information System (INIS)

    The frequency of urinary tract infection before and during pelvic radiotherapy was studied prospectively in 172 patients who were not catherised and had not had instrumentation for at least 4 weeks prior to radiotherapy. The incidence of urinary tract infection prior to radiotherapy was 17% and a further 17% of patients develped a urinary tract infection during radiotherapy. Mid-stream specimens of urine (MSU) should be examined for infection on a weekly basis during pelvic radiotherapy not only to identify this additional 17% of patients but also to detect those patients who have persistent urinary tract infection in spite of treatment with appropriate antibiotics. (author). 6 refs.; 1 fig.; 4 tabs

  18. Randomised phase I/II study to evaluate carbon ion radiotherapy versus fractionated stereotactic radiotherapy in patients with recurrent or progressive gliomas: The CINDERELLA trial

    Directory of Open Access Journals (Sweden)

    Haselmann Renate

    2010-10-01

    Full Text Available Abstract Background Treatment of patients with recurrent glioma includes neurosurgical resection, chemotherapy, or radiation therapy. In most cases, a full course of radiotherapy has been applied after primary diagnosis, therefore application of re-irradiation has to be applied cauteously. With modern precision photon techniques such as fractionated stereotactic radiotherapy (FSRT, a second course of radiotherapy is safe and effective and leads to survival times of 22, 16 and 8 months for recurrent WHO grade II, III and IV gliomas. Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE, which can be calculated between 2 and 5 depending on the GBM cell line as well as the endpoint analyzed. Protons, however, offer an RBE which is comparable to photons. First Japanese Data on the evaluation of carbon ion radiation therapy for the treatment of primary high-grade gliomas showed promising results in a small and heterogeneous patient collective. Methods Design In the current Phase I/II-CINDERELLA-trial re-irradiation using carbon ions will be compared to FSRT applied to the area of contrast enhancement representing high-grade tumor areas in patients with recurrent gliomas. Within the Phase I Part of the trial, the Recommended Dose (RD of carbon ion radiotherapy will be determined in a dose escalation scheme. In the subsequent randomized Phase II part, the RD will be evaluated in the experimental arm, compared to the standard arm, FSRT with a total dose of 36 Gy in single doses of 2 Gy. Primary endpoint of the Phase I part is toxicity. Primary endpoint of the randomized part II is survival after re-irradiation at 12 months, secondary endpoint is progression-free survival. Discussion The

  19. Computer simulation of tumour growth and cellular phase distribution prior to radiotherapy

    International Nuclear Information System (INIS)

    Full text: A study into the optimal fractionation and schedule in combined chemo-radiotherapy for head and neck cancer has imposed the development of a computer model of tumour growth. The model is based on biological parameters, and characterises tumour growth and eventual tumour regression when chemo-radiotherapy is used. Tumour growth starting from a single stem cell is modelled using the Monte Carlo method. The type of the cell function, their relative proportions on mitosis, their proliferative capacity, the duration of the four phases of the cell cycle, the mean cell cycle time, and the cell loss due to natural causes are the main parameters of the basic model. A Gaussian distribution function operates in establishing the cell cycle time, with a mean value of 26 hours, while the cell type is sampled from a uniform distribution. With the established model, the sensitivity of the developed tumour's cell population to the stem, proliferative and non proliferative ratio at mitosis was assessed. The present model accurately reflects the exponential distribution of cells along the cell cycle (70% cells in G1 phase, 15% in S, 10% in G2, 5% in M) of a developed tumour as described in the literature. The proportion of stem, finitely proliferating and resting cells during tumour growth is maintained within their biological limits (2% stem. 23% finitely proliferating, 75% nonproliferating cells). The ratio (R=3) between the time necessary to develop a clinically detectable tumour (109 cells) and the time to grow to its lethal size (1012 cells) is in accordance with the biological data when tumour volume is compared for the two periods (30 doublings and 10 doublings respectively). Computer simulation can illustrate the biological growth of a tumour and the cell distribution along the cell cycle. These distributions may than be used in the assessment of tumour response to radiotherapy and to specific chemotherapeutic agents. Copyright (2001) Australasian College of

  20. Film dosimetry in conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Danciu, C.; Proimos, B.S. [Patras Univ. (Greece). Dept. of Medical Physics

    1995-12-01

    Dosimetry, through a film sandwiched in a transverse cross-section of a solid phantom, is a method of choice in Conformal Radiotherapy because: (a) the blackness (density) of the film at each point offers a measure of the total dose received at that point, and (b) the film is easily calibrated by exposing a film strip in the same cross-section, through a stationary field. The film must therefore have the following properties: (a) it must be slow, in order not to be overexposed, even at a therapeutic dose of 200 cGy, and (b) the response of the film (density versus dose curve) must be independent of the photon energy spectrum. A few slow films were compared. It was found that the Kodak X-Omat V for therapy verification was the best choice. To investigate whether the film response was independent of the photon energy, response curves for six depths, starting from the depth of maximum dose to the depth of 25 cm, in solid phantom were derived. The vertical beam was perpendicular to the anterior surface of the phantom, which was at the distance of 100 cm from the source and the field was 15x15 cm at that distance. This procedure was repeated for photon beams emitted by a Cobalt-60 unit, two 6 MV and 15 MV Linear Accelerators, as well as a 45 MV Betatron. For each of those four different beams the film response was the same for all six depths. The results, as shown in the diagrams, are very satisfactory. The response curve under a geometry similar to that actually applied, when the film is irradiated in a transverse cross-section of the phantom, was derived. The horizontal beam was almost parallel (angle of 85) to the plane of the film. The same was repeated with the central ray parallel to the film (angle 90) and at a distance of 1.5 cm from the horizontal film. The field size was again 15x15 at the lateral entrance surface of the beam. The response curves remained the same, as when the beam was perpendicular to the films.

  1. Similar Outcomes of Standard Radiotherapy and Hypofractionated Radiotherapy Following Breast-Conserving Surgery

    OpenAIRE

    Hou, Hai-Ling; Song, Yong-Chun; Li, Rui-Ying; Zhu, Li; Zhao, Lu-Jun; Yuan, Zhi-yong; You, Jin-Qiang; Chen, Zhong-Jie; Wang, Ping

    2015-01-01

    Background Adjuvant radiation therapy is commonly administered to breast cancer patients who received breast-conserving surgery. However, lengthy treatment times of standard radiotherapy pose certain challenges. Here, we performed a prospective controlled study comparing standard radiation to hypofractionated radiotherapy in terms of efficacy and outcome. Material/Methods Eighty breast cancer patients (tumor stage pT1-2N0-1M0) who had undergone breast-conservation surgery were randomly divide...

  2. Dosimetric absorption of intensity-modulated radiotherapy compared with conventional radiotherapy in breast-conserving surgery

    OpenAIRE

    Lin, Yang; WANG, BENZHONG

    2014-01-01

    The aim of this study was to investigate the dosimetric benefits between intensity-modulated radiotherapy (IMRT) and conventional radiotherapy (CR) among patients receiving breast-conserving surgery. A dosimetric comparison of IMRT and CR was evaluated in 20 patients with early-stage breast cancer using a three-dimensional treatment planning system. The prescribed mammary gland dose was completed in 25 fractions with a total dose of 5,000 cGy. Homogeneity of the planning target volume (PTV), ...

  3. Locoregional post-mastectomy radiotherapy for breast cancer: literature review

    International Nuclear Information System (INIS)

    Postoperative radiotherapy is controversial after radical mastectomy. Recent clinical trials have shown an increase in survival with this irradiation and conclusions of previous meta-analyses should be reconsidered and conclusions of previous meta-analyses should be reconsidered. The results of a large number of randomized clinical trials in which women received post-mastectomy radiotherapy or not have been renewed. These trials showed a decrease in locoregional failure with the use of postoperative radiotherapy but survival advantages have not been clearly identified. A large number of randomized clinical trials compared postoperative radiotherapy alone, chemotherapy alone and the association of the two treatments. They showed that chemotherapy was less active locally than radiotherapy and that radiotherapy and chemotherapy significantly increased both disease-free and overall survival rates in the groups which received postoperative radiotherapy. These favourable results were, however, obtained with optimal radiotherapy techniques and a relative sparing of lung tissue and cardiac muscle. Many retrospective clinical analyses concluded that results obtained in locoregional failure rate were poor and that these failures led to an increase in future risks. Both radiotherapy and systemic treatment should be delivered after mastectomy, reserved for patients with a high risk of with a diameter ≥ 5 cm. However, radiotherapy could produce secondary effects, and techniques of radiotherapy should be optimal. (author)

  4. Barriers to palliative radiotherapy referral: A Canadian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Samant, Rajiv S.; Fitzgibbon, Edward; Meng, Joanne; Graham, Ian D. [Univ. of Ottawa. Ottawa, ON (Canada)

    2007-07-15

    Radiotherapy is an effective but underutilized treatment modality for cancer patients. We decided to investigate the factors influencing radiotherapy referral among family physicians in our region. A 30-item survey was developed to determine palliative radiotherapy knowledge and factors influencing referral. It was sent to 400 physicians in eastern Ontario (Canada) and the completed surveys were evaluated. The overall response rate was 50% with almost all physicians seeing cancer patients recently (97%) and the majority (80%) providing palliative care. Approximately 56% had referred patients for radiotherapy previously and 59% were aware of the regional community oncology program. Factors influencing radiotherapy referral included the following: waiting times for radiotherapy consultation and treatment, uncertainty about the benefits of radiotherapy, patient age, and perceived patient inconvenience. Physicians who referred patients for radiotherapy were more than likely to provide palliative care, work outside of urban centres, have hospital privileges and had sought advice from a radiation oncologist in the past. A variety of factors influence the referral of cancer patients for radiotherapy by family physicians and addressing issues such as long waiting times, lack of palliative radiotherapy knowledge and awareness of Cancer Centre services could increase the rate of appropriate radiotherapy patient referral.

  5. Barriers to palliative radiotherapy referral: A Canadian perspective

    International Nuclear Information System (INIS)

    Radiotherapy is an effective but underutilized treatment modality for cancer patients. We decided to investigate the factors influencing radiotherapy referral among family physicians in our region. A 30-item survey was developed to determine palliative radiotherapy knowledge and factors influencing referral. It was sent to 400 physicians in eastern Ontario (Canada) and the completed surveys were evaluated. The overall response rate was 50% with almost all physicians seeing cancer patients recently (97%) and the majority (80%) providing palliative care. Approximately 56% had referred patients for radiotherapy previously and 59% were aware of the regional community oncology program. Factors influencing radiotherapy referral included the following: waiting times for radiotherapy consultation and treatment, uncertainty about the benefits of radiotherapy, patient age, and perceived patient inconvenience. Physicians who referred patients for radiotherapy were more than likely to provide palliative care, work outside of urban centres, have hospital privileges and had sought advice from a radiation oncologist in the past. A variety of factors influence the referral of cancer patients for radiotherapy by family physicians and addressing issues such as long waiting times, lack of palliative radiotherapy knowledge and awareness of Cancer Centre services could increase the rate of appropriate radiotherapy patient referral

  6. Comparison of concurrent chemo-radiotherapy and sequential chemo-radiotherapy for locally advanced non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: Prospective comparison was done on concurrent chemo-radiotherapy and sequential chemo-radiotherapy for unresectable stage III non-small cell lung cancer (NSCLC) and to evaluate three different regimens of concurrent chemo-radiotherapy. Methods: Ninety-six such patients were randomized into four groups: 1. sequential chemo-radiotherapy group received two cycles of induction chemotherapy with 40 mg/m2 of cisplatin on D 1-3, 29-31 and 100 mg/m2 of etoposide on D 1-3, 29-31 before conventional radiotherapy, 2. concurrent chemo-radiotherapy group 1 received 100 mg/m2 etoposide on D 1-3 and DDP 40 mg/m2 on D 1-3, D 29-31, iv. drip, 3. concurrent chemo-radiotherapy group 2 received concurrent chemotherapy with 40 mg/m2 of paclitaxel every Monday during conventional radiotherapy, 4. concurrent chemo-radiotherapy group 3 received concurrent chemotherapy with 40 mg/m2 of paclitaxel every Monday during three-dimensional conformal radiotherapy. All patients were irradiated with 2.0 Gy/fraction, 5 fractions/week, to a total dose of 60 -64 Gy. They all received two cycles of consolidation themotherapy with 40 mg/m2 of cisplatin on D 1-3 and 100 mg/m2 of etoposide on D 1-3. Results: The overall response rate was 67%, 71%, 71% and 79% for sequential chemo-radiotherapy group, concurrent chemo-radiotherapy group 1, 2 and 3, respectively. There was a significant difference between the concurrent chemo-radiotherapy and sequential chemo-radiotherapy(P0.05) also was the difference of toxicity (P>0.05), but the severe toxicity of concurrent chemo-radiotherapy groups 1 and 2 were higher than the sequential chemo-radio-therapy group and concurrent chemo-radiotherapy group 3. Conclusions: Better locoregional progression-free survival and overall survival of unresectable stage III non-small cell lung cancer could be achieved by concurrent chemo-radiotherapy as compared with sequential chemo-radiotherapy though at the expense of in- crease in toxicity. With the combination of

  7. The IAEA Quality Audits for Radiotherapy

    International Nuclear Information System (INIS)

    The IAEA/WHO thermoluminescent dosimetry (TLD) postal dose audit programme has been used for over 8000 radiotherapy beams throughout the world in over four decades of its operation. Records have been kept of the results of TLD audits since the inception of the programme. Analysis of these data has yielded much interesting information. In the early years, the TLD service recorded approximately 50% audited beams having adequate calibration. This percentage of acceptable results has now increased to 96%. Obviously, regular participation in dosimetry audit stimulates an improvement in dosimetry practices in radiation therapy in many hospitals worldwide. Another dosimetry audit programme for treatment planning (TPS audit) in external beam radiotherapy, which has been developed by the IAEA, assesses the radiotherapy workflow for conformal techniques, from patient data acquisition and computerized treatment planning to dose delivery. The IAEA supports national and subregional TPS audit activities to improve the quality and safety of dose calculation in radiotherapy. The third audit modality operated by the IAEA within the framework of the Quality Assurance Team for Radiation Oncology (QUATRO) is a comprehensive audit that reviews radiation oncology practices with the aim to improve quality. To date, over 50 QUATRO audits have been organized by the IAEA in radiation oncology centres in Europe, Africa, Asia and Latin America. QUATRO audits indicate and document areas for improvement and provide advice for further development of the audited centres. (author)

  8. Tumour-host dynamics under radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Placeres Jimenez, Rolando, E-mail: rpjcu@yahoo.com [Departamento de Fi' sica, Universidade Federal de Sao Carlos, Sao Carlos - SP (Brazil); Ortiz Hernandez, Eloy [Centre of Medicine and Complexity, Medical University Carlos J. Finlay, Carretera Central s/n, Camagueey (Cuba)

    2011-09-15

    Highlight: > Tumour-host interaction is modelled by Lotka-Volterra equations. > A brief review of the motion integral and analysis of linear stability is presented. > Radiotherapy is introduced into the model, using a periodic Dirac delta function. > A two-dimensional logistic map is derived from the modified Lotka-Volterra model. > It is shown that tumour can be controlled by a correct selection of therapy strategy. - Abstract: Tumour-host interaction is modelled by the Lotka-Volterra equations. Qualitative analysis and simulations show that this model reproduces all known states of development for tumours. Radiotherapy effect is introduced into the model by means of the linear-quadratic model and the periodic Dirac delta function. The evolution of the system under the action of radiotherapy is simulated and parameter space is obtained, from which certain threshold of effectiveness values for the frequency and applied doses are derived. A two-dimensional logistic map is derived from the modified Lotka-Volterra model and used to simulate the effectiveness of radiotherapy in different regimens of tumour development. The results show the possibility of achieving a successful treatment in each individual case by employing the correct therapeutic strategy.

  9. Late toxicity in breast cancer radiotherapy

    International Nuclear Information System (INIS)

    Full text: The aim of this study is to describe and classify chronic complications due to radiotherapy in breast cancer. Also the impact of radiotherapy on the quality of life of patients is evaluated. Materials and methods: 50 patients with breast cancer at early stages (78% in situ, 22% I and II) treated with radiotherapy in breast volume plus boost (45/50 Gy + 18/20 Gy) with a follow up over 5 years. Acute toxicities were found retrospectively and chronic toxicities were assessed though physical examination and review of complementary studies. To facilitate data collection, pre printed forms were used. Bibliographic searches were made. Results: 10% received chemotherapy and 64% tamoxifen. The predominant chronic toxicity were found in skin (66%), although grade I and II (hyperpigmentation 26%, dryness 22%, telangiectasia 10% fibrosis, 4%, other 4%). A 50% of the patients showed hypoesthesia in ipsilateral upper limb. The other toxicities were presented in low rate and magnitude: mastodynia 16%; actinic pneumonitis 4%, pyrosis 4%, Tachycardia 2%, among others. Of the patients with acute toxicity, only 30% were grade III. The 70% of the patients had a positive impact of radiotherapy on quality of life. Conclusions: We found low rates and degrees of late toxicity. It was noticed a relationship between acute and chronic toxicity, because those who presented adverse effects during treatment developed late effects. It reflects the importance of integrating monitoring as part of radiation treatment. It should be adopted a single score of late toxicity measurement to unify data from different series. (authors)

  10. Clinical results in heavy particle radiotherapy

    International Nuclear Information System (INIS)

    The chapter presents an overview of the use of heavy particles in human cancer radiotherapy. The biophysical characteristics and rationale for using heavy charged particle therapy are explored. The clinical experience with carbon, neon, argon and helium are summarized for various types of tumors including carcinomas of the uterine cervix and lung, skin melanomas and metastatic sarcomas. No obvious normal tissue complications have appeared

  11. Symptomatic vertebral hemangioma: Treatment with radiotherapy

    Directory of Open Access Journals (Sweden)

    Aich Ranen

    2010-01-01

    Full Text Available Background: Vertebrae are the second commonest site among skeletal locations affected by hemangioma, but only about one per cent becomes symptomatic throughout the life. Though surgery, intra vertebral injection of various sclerosing agents have been tried in treating this benign process, no general consensus regarding management has been reached. Radiotherapy is emerging as a low cost, simple, non-invasive but very effective modality of treatment of symptomatic vertebral hemangioma. Aim: This study aims to find out the role of external beam radiotherapy in alleviating the symptoms of symptomatic vertebral hemangiomas without compromising the quality of life. Materials and Methods: Seven consecutive patients with symptomatic vertebral hemangioma were treated with a fixed dose of external beam radiotherapy; and muscle power was assessed before, after treatment and during follow-up. Results: All patients showed improvement of muscle power, which increased with the passage of time. Pain relief with improvement of quality of life was obtained in all the patients. Conclusion: Effect of radiotherapy on vertebral hemangioma is dose-dependent and the dose limiting factor is the spinal cord tolerance. In the present era of IMRT, greater dose can be delivered to the parts of vertebra affected by the hemangioma without compromising the spinal cord tolerance and expected to give better results.

  12. Results of the national audit in radiotherapy

    International Nuclear Information System (INIS)

    The National Audit Programme in Radiotherapy in Cuba working for 8 years regularly visiting each country's radiotherapy service at least once every two years, during the visit involving two medical physicists and radiation oncologist. This paper presents the main features of the program and its main results. Early detection deficiencies in the work of the Radiation Therapy Services that may cause radiological risk situations for both patients and workers and the general public. Help with their comments to the continuous improvement of quality of care. During audit visits is reviewed the whole process of radiotherapy, since the patient comes to the monitoring service. This is done by dividing the audits into three groups or aspects: Clinical Aspects, Aspects of Safety and Quality Control Aspects of the equipment. Methodological guidelines have been established for conducting audits and they serve as standards of quality in radiation therapy, these guidelines also allow the quantification of results. It has identified the main gaps in services that affect the quality of care. After each visit, leave recommendations may be directed to the service itself, to the direction of the provincial hospital or health. Conclusions. We believe that the National Audit Programme in Radiotherapy is an effective tool in controlling the quality of the treatments offered and at the same time with its recommendations helps services to continually improve quality. (Author)

  13. Magnetic resonance imaging in radiotherapy treatment planning

    NARCIS (Netherlands)

    Moerland, Marinus Adriaan

    2001-01-01

    From its inception in the early 1970's up to the present, magnetic resonance imaging (MRI) has evolved into a sophisticated technique, which has aroused considerable interest in var- ious subelds of medicine including radiotherapy. MRI is capable of imaging in any plane and does not use ionizing rad

  14. Post-external radiotherapy hypothyroidism: 15 cases

    International Nuclear Information System (INIS)

    Post-external radiotherapy hypothyroidism: 15 cases. Hypothyroidism frequency is estimated to be between 10 and 45% after radiotherapy alone, and 40 to 67% after radiotherapy associated with thyroidectomy. This hypothyroidism is infra-clinical in 60% of the cases. Our study concerned 15 cases of hypothyroidism after external radiotherapy delivered between and 1991 and 1999. An irradiation of the cervical, cerebral and thorax regions was indicated for different types of cancers. Larynx carcinoma epidermoid was the most frequent cancer (seven cases); the radiation treatment used cobalt 60 with conventional fractionation, i.e., 2 Gy per treatment, five treatments a week. In nine cases, the hypothyroidism was discovered during a systematic examination; it was clinically evident in the six remaining cases. Hypothyroidism appeared after an irradiation dose average of 50 Gy (extremes 30-65 Gy). The average duration of the irradiation was about 7 weeks and the hypothyroidism appeared in a mean 22 months. In all cases, the substituting treatment was initiated with a favorable progression. Faced with the risk of hypothyroidism, it is necessary to check patients who have undergone external irradiation of the neck. (authors)

  15. Radiotherapy for breast cancer and erythrokeratodermia variabilis.

    Science.gov (United States)

    Pernin, V; Kirova, Y; Campana, F

    2014-12-01

    We report the first case report indicating that locoregional radiotherapy provide acceptable early and late toxicities in patient with erythrokeratodermia variabilis after 2 years of follow-up. However, preclinical data showing radiation-induced tumor genesis in case of deficiency of some connexins point out the need of a careful surveillance of these patients. PMID:25306447

  16. Linac based radiosurgery and stereotactic radiotherapy

    International Nuclear Information System (INIS)

    The following topics were discussed: Definition of stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT); Stereo market; Indications for SRS/SRT; History of linac-based SRS/SRT; Variety of systems; QA for SRS; Localization; and Imaging. (P.A.)

  17. Radiotherapy for prostate cancer and sexual health

    NARCIS (Netherlands)

    L. Incrocci (Luca)

    2015-01-01

    textabstractSexual dysfunction is very common after treatment of prostate cancer. Radiation therapy together with radical prostatectomy is the most effective treatment for localized disease. Percentages of erectile dysfunction (ED) reported in prospective studies after external-beam radiotherapy (RT

  18. Radiotherapy for Peyronie's Disease: A European survey

    International Nuclear Information System (INIS)

    Background and purpose. Peyronie's Disease (PD) is a benign condition characterized by penile nodules, pain and curvature. Radiotherapy has been used for many years with positive outcomes, however all studies published were non-randomized or non-controlled. The purpose of this survey was to understand which treatment policy is followed in Europe before setting up a randomized trial. Materials and methods. A questionnaire was sent out to 908 European radiotherapy institutions, 402 questionnaires were sent back and filled out correctly (44.5%). The questionnaire consisted of different items, regarding number of patients referred, fraction dose, total dose and technique used, and eventually treatment outcome of clinical trials. Results. Seventy-three institutions irradiate PD (19%), 304 do not (81%). Reasons for not treating were insufficient referrals from urologists or no interest in treating benign diseases. The most common fraction dose is 2 (range 0.5-8) Gy and the total radiation dose 20 (range 3-30) Gy. Most of the institutions use electrons (n = 44) or orthovoltage (n = 32). Decreased pain is reported in about 80% of the cases, and side effects by eight institutions. Conclusions. So far, a large variation of treatment schedules for radiotherapy of PD has been detected in European countries. Although the results are good and side effects minimal, there is still a need to set up a European randomized trial to prospectively evaluate the efficacy of radiotherapy for PD

  19. The Role of Radiotherapy in Acromegaly.

    Science.gov (United States)

    Hannon, Mark J; Barkan, Ariel L; Drake, William M

    2016-01-01

    Radiotherapy has, historically, played a central role in the management of acromegaly, and the last 30 years have seen substantial improvements in the technology used in the delivery of radiation therapy. More recently, the introduction of highly targeted radiotherapy, or 'radiosurgery', has further increased the therapeutic options available in the management of secretory pituitary tumors. Despite these developments, improvements in primary surgical outcomes, an increase in the range and effectiveness of medical therapy options, and long-term safety concerns have combined to dictate that, although still deployed in selected cases, the use of radiotherapy in the management of acromegaly has declined steadily over the past 2 decades. In this article, we review some of the main studies that have documented the efficacy of pituitary radiotherapy on growth hormone hypersecretion and summarize the data around its potential deleterious effects, including hypopituitarism, cranial nerve damage, and the development of radiation-related intracerebral tumors. We also give practical recommendations to guide its future use in patients with acromegaly, generally, as a third-line intervention after neurosurgical intervention in combination with various medical therapy options. PMID:26088716

  20. The spanish radiotherapy park: past and present

    International Nuclear Information System (INIS)

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

  1. Secondary cancers after radiotherapy: an introduction

    International Nuclear Information System (INIS)

    Being intentional, delivering high radiation doses in well-defined volumes for cancer patients, radiotherapy poses a specific problem in terms of radio-induced secondary neoplasias. Actually, second cancers after radiotherapy have been almost ignored for decades, mostly because oncologists had not available large series of patients cured of cancer with more than 10-15 years of follow-up. Only anecdotal cases were reported (skin carcinomas, thyroid cancers, soft tissue sarcomas, osteosarcomas after retinoblastoma irradiation...). The picture changed in the 80's, in particular when large series of Hodgkin's disease patients were analyzed after a long follow-up. Second solid tumours were found to be significantly related to irradiation, and more precisely to dose and extend of radiation. In parallel, data from breast radiotherapy (for cancer or benign diseases), from fluoroscopy and atomic explosions, also suggested a small but increase in risk of breast cancer after a few Gy. Although the risk/benefit ratio remains usually exceedingly small, radiotherapy should help to answer two additional basic questions: In a group of irradiated patients, can we individualize those cancers induced by radiation from those which were not? and is there within the cancer patient population a subgroup of individuals more prone to cancer radio-induction (and for whom strategy should be possibly readapted)? (author)

  2. Quality assurance for image-guided radiotherapy

    International Nuclear Information System (INIS)

    The topics discussed include, among others, the following: Quality assurance program; Image guided radiotherapy; Commissioning and quality assurance; Check of agreement between visual and displayed scales; quality controls: electronic portal imaging device (EPID), MV-kV and kV-kV, cone-beam CT (CBCT), patient doses. (P.A.)

  3. Palliative radiotherapy for symptomatic osseous metastases

    International Nuclear Information System (INIS)

    Bone matastases are one of the most common and serious conditions requiring radiotherapy, but there is still a considerable lack of agreement on optimal radiation schedule. We analyzed patients with symptomatic osseous matastases from lung (72 patients) and breast (63 patients) carcinoma treated by palliative radiotherapy between 1983 and 1992. In this series, the incidences of symptomatic bone metastases appearing within 2 years after the first diagnosis of the primary lesion were 96% and 36% for lung and breast carcinomas, respectively. Thirty percent of bone metastases from breast carcinoma were diagnosed more than 5 years after the first diagnosis. Thus careful follow-up must be carried out for a prolonged period. Pain relief was achieved at almost the same rate for bone metastases from lung and breast carcinomas (81% and 85%, respectively), an the rapid onset of pain relief (15 Gy or less) was obtained in about half the patients for both diseases. The rapid onset of pain relief and the lack of association between the onset of pain relief and primary tumor argued against the conventional theory that tumor shrinkage is a component of the initial response. In contrast to the fact that almost all lung carcinoma patients had very poor prognoses, one third of the breast carcinoma patients were alive more than 2 years after palliative radiotherapy. Thust, the late effects of radiation, such as radiation myelopathy, must be always considered especially in breast carcinoma patients even when it is 'just' palliative radiotherapy for bone metastases. (author)

  4. Simple dose verification system for radiotherapy radiation

    International Nuclear Information System (INIS)

    The aim of this paper is to investigate an accurate and convenient quality assurance programme that should be included in the dosimetry system of the radiotherapy level radiation. We designed a mailed solid phantom and used TLD-100 chips and a Rexon UL320 reader for the purpose of dosimetry quality assurance in Taiwanese radiotherapy centers. After being assembled, the solid polystyrene phantom weighted only 375 g which was suitable for mailing. The Monte Carlo BEAMnrc code was applied in calculations of the dose conversion factor of water and polystyrene phantom: the dose conversion factor measurements were obtained by switching the TLDs at the same calibration depth of water and the solid phantom to measure the absorbed dose and verify the accuracy of the theoretical calculation results. The experimental results showed that the dose conversion factors from TLD measurements and the calculation values from the BEAMnrc were in good agreement with a difference within 0.5%. Ten radiotherapy centers were instructed to deliver to the TLDs on central beam axis absorbed dose of 2 Gy. The measured doses were compared with the planned ones. A total of 21 beams were checked. The dose verification differences under reference conditions for 60Co, high energy X-rays of 6, 10 and 15 MV were truly within 4% and that proved the feasibility of applying the method suggested in this work in radiotherapy dose verification

  5. Progress of cervical cancer genetic-radiotherapy

    International Nuclear Information System (INIS)

    Although cervical cancer gene therapy has a distance to clinical use due to some problems, the combinating of irradiation and gene therapy holds much promise in cancer therapy based on the traditional radiotherapy, chemotherapy and surgery. This review focuses on the group of radiogenic therapy that are either. (authors)

  6. Clinical research of teeth damage from radiotherapy

    International Nuclear Information System (INIS)

    Objective: To analyze various factors inducing teeth damage from radiotherapy and the preventive and treatment methods. Methods: One hundred cases of patients treated by radiotherapy were divided into two groups. In group one there were 60 cases whose teeth were irradiated during treatment; in group two there were 40 cases whose teeth were not irradiated during treatment. Results: The caries incidence was 60% for group one and 15% for group two (P<0.01). By auto-control in 15 patients, the caries incidence on the sick side was obviously higher than that of the healthy side. Hundred percent caries incidence was found in 6 cases who received a dosage of 70 Gy. Conclusion: The authors believe that radiation damage to the teeth is associated with the following factors: 1. The dosage and location of irradiation are closely related to caries incidence; 2. The active dentinoblasts are very sensitive to radiation; 3. Damage to the salivary glands from radiotherapy can result in reduction of salvia and pH value, leading to a high growth rate of Streptococcus mutans. Following preventive measures could be considered in future cases: to apply a caries prevention coating or protective dental crown and TPS, to adjust the dose and time of irradiation, to select conformal radiotherapy technique. The key points for protecting the teeth and salivary gland from caries and damage are protection of the proliferation ability of pulp cells, anti-inflammation, promotion of microcirculation, and strengthening body resistance

  7. Reirradiation Human Spinal Cord Tolerance for Stereotactic Body Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Sahgal, Arjun, E-mail: Arjun.sahgal@rmp.uhn.on.ca [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Princess Margaret Hospital, University of Toronto, Toronto (Canada); Ma, Lijun [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States); Weinberg, Vivian [University of California San Francisco Helen Diller Family Comprehensive Cancer Center Biostatistics Core, San Francisco, CA (United States); Gibbs, Iris C. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Chao, Sam [Departments of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, OH (United States); Chang, Ung-Kyu [Department of Neurosurgery, Korea Institute of Radiation and Medical Science, Seoul (Korea, Republic of); Werner-Wasik, Maria [Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, PA (United States); Angelov, Liliyanna [Departments of Radiation Oncology and Neurosurgery, Cleveland Clinic, Cleveland, OH (United States); Chang, Eric L. [Department of Radiation Oncology, M.D. Anderson Cancer Center, University of Texas, Houston, TX (United States); Sohn, Moon-Jun [Department of Neurosurgery, Inje University, Seoul (Korea, Republic of); Soltys, Scott G. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Letourneau, Daniel [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto (Canada); Ryu, Sam [Department of Radiation Oncology, Henry Ford Hospital, Detroit, MI (United States); Gerszten, Peter C. [Departments of Neurological Surgery and Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Fowler, Jack [Departments of Human Oncology and Medical Physics, University of Wisconsin, WI (United States); Wong, C. Shun [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto (Canada); and others

    2012-01-01

    Purpose: We reviewed the treatment for patients with spine metastases who initially received conventional external beam radiation (EBRT) and were reirradiated with 1-5 fractions of stereotactic body radiotherapy (SBRT) who did or did not subsequently develop radiation myelopathy (RM). Methods and Materials: Spinal cord dose-volume histograms (DVHs) for 5 RM patients (5 spinal segments) and 14 no-RM patients (16 spine segments) were based on thecal sac contours at retreatment. Dose to a point within the thecal sac that receives the maximum dose (P{sub max}), and doses to 0.1-, 1.0-, and 2.0-cc volumes within the thecal sac were reviewed. The biologically effective doses (BED) using {alpha}/{beta} = 2 Gy for late spinal cord toxicity were calculated and normalized to a 2-Gy equivalent dose (nBED = Gy{sub 2/2}). Results: The initial conventional radiotherapy nBED ranged from {approx}30 to 50 Gy{sub 2/2} (median {approx}40 Gy{sub 2/2}). The SBRT reirradiation thecal sac mean P{sub max} nBED in the no-RM group was 20.0 Gy{sub 2/2} (95% confidence interval [CI], 10.8-29.2), which was significantly lower than the corresponding 67.4 Gy{sub 2/2} (95% CI, 51.0-83.9) in the RM group. The mean total P{sub max} nBED in the no-RM group was 62.3 Gy{sub 2/2} (95% CI, 50.3-74.3), which was significantly lower than the corresponding 105.8 Gy{sub 2/2} (95% CI, 84.3-127.4) in the RM group. The fraction of the total P{sub max} nBED accounted for by the SBRT P{sub max} nBED for the RM patients ranged from 0.54 to 0.78 and that for the no-RM patients ranged from 0.04 to 0.53. Conclusions: SBRT given at least 5 months after conventional palliative radiotherapy with a reirradiation thecal sac P{sub max} nBED of 20-25 Gy{sub 2/2} appears to be safe provided the total P{sub max} nBED does not exceed approximately 70 Gy{sub 2/2}, and the SBRT thecal sac P{sub max} nBED comprises no more than approximately 50% of the total nBED.

  8. Reirradiation Human Spinal Cord Tolerance for Stereotactic Body Radiotherapy

    International Nuclear Information System (INIS)

    Purpose: We reviewed the treatment for patients with spine metastases who initially received conventional external beam radiation (EBRT) and were reirradiated with 1–5 fractions of stereotactic body radiotherapy (SBRT) who did or did not subsequently develop radiation myelopathy (RM). Methods and Materials: Spinal cord dose–volume histograms (DVHs) for 5 RM patients (5 spinal segments) and 14 no-RM patients (16 spine segments) were based on thecal sac contours at retreatment. Dose to a point within the thecal sac that receives the maximum dose (Pmax), and doses to 0.1-, 1.0-, and 2.0-cc volumes within the thecal sac were reviewed. The biologically effective doses (BED) using α/β = 2 Gy for late spinal cord toxicity were calculated and normalized to a 2-Gy equivalent dose (nBED = Gy2/2). Results: The initial conventional radiotherapy nBED ranged from ∼30 to 50 Gy2/2 (median ∼40 Gy2/2). The SBRT reirradiation thecal sac mean Pmax nBED in the no-RM group was 20.0 Gy2/2 (95% confidence interval [CI], 10.8–29.2), which was significantly lower than the corresponding 67.4 Gy2/2 (95% CI, 51.0–83.9) in the RM group. The mean total Pmax nBED in the no-RM group was 62.3 Gy2/2 (95% CI, 50.3–74.3), which was significantly lower than the corresponding 105.8 Gy2/2 (95% CI, 84.3–127.4) in the RM group. The fraction of the total Pmax nBED accounted for by the SBRT Pmax nBED for the RM patients ranged from 0.54 to 0.78 and that for the no-RM patients ranged from 0.04 to 0.53. Conclusions: SBRT given at least 5 months after conventional palliative radiotherapy with a reirradiation thecal sac Pmax nBED of 20–25 Gy2/2 appears to be safe provided the total Pmax nBED does not exceed approximately 70 Gy2/2, and the SBRT thecal sac Pmax nBED comprises no more than approximately 50% of the total nBED.

  9. Radiotherapy for the primary ocular adnexal lymphoma

    International Nuclear Information System (INIS)

    Objective: To study the pathological and clinical characteristics of primary lymphoma of ocular adnexae, analyze the treatment results and discuss the methods to prevent radiation complications. Methods: From Feb. 1995 to Feb. 2004, 25 patients with primary ocular adnexal lymphoma were treated in the second hospital and the forth hospital of Xuzhou, including 11 males and 14 females. The diagnosis was confirmed pathologically by biopsy in 19 patients and lumpectomy in 6 patients, including 22 mucosa-associated lymphoid tissue (MALT) lymphoma and 3 non-MALT lymphoma. According to the Ann Arbor Staging System, there were 21 patients with tumor in stage I E, 3 in stage II E and 1 in stage III E. The primary tumor was found in the eyelid or conjunctiva in 19 eyes and orbit in 9 eyes. Radiotherapy were given to 22 patients (25 eyes) by deep X-rays, 60Co γ-rays or mixed beams. The total irradiation dose ranged from 30.0 to 57.6 Gy. Kaplan-Meier method was used to calculate the survival rate and Logrank test was used to detect the difference between the different groups. Results: The 5-, 10-year accumulated survival rates (SR) of the whole group were 90% and 82%. The 10-year SR of patients with primary, eyelid or conjunctiva tumor and orbit tumor were 100% and 58% (P=0.032). The local control rates of the radiotherapy group and non-radiotherapy group were 92% and 33 % (P=0.006). The 10-year SR of patients with tumor completely removed and those with residues were 83% and 82% (P=0.907). The 10-year SR of MALT lymphoma and non-MALT lymphoma were 90.0% and 33.3% (P=0.009). After radiotherapy, 8 eyes (36%) had cataract formation and 7 eyes (28%) had xerophalmic symptoms. Conclusions: The results of radiothera- py for the primary ocular adnexal lymphoma are satisactory. The prognosis of patients with primary, eyelid or conjunctiva tumor is better than those with orbit tumor. The vast majority of the primary ocular adnexal lymphomas are MALT lymphomas. The survival rate of

  10. Planning national radiotherapy services: A practical tool

    International Nuclear Information System (INIS)

    Cancer is a leading cause of death globally. The World Health Organization (WHO) estimates that 7.6 million people died of cancer in 2005 and 84 million people will die of the disease in the next ten years if action is not taken. More than 70% of all cancer deaths occur in low and middle income countries (LMCs), where resources available for prevention, diagnosis and treatment are limited or non-existent. In high income countries, about 50% of new cases of cancer require radiotherapy at least once. Because of the types of cancer, the advanced nature of the cases at diagnosis and the lack of other resources, the proportion of new cases requiring radiotherapy is likely to be much higher in LMCs. During the last few years, there has been an increased demand from Member States for the IAEA to provide assistance, including the provision of radiation sources and equipment in establishing radiotherapy programmes for the treatment of cancer. The IAEA is the United Nations system organization with a mandate in nuclear technology transfer for nuclear applications in human health. Through its human health programme, the IAEA coordinates research projects, produces and publishes teaching materials and clinical guidelines, maintains databases, and delivers laboratory services to Member States worldwide. The Programme of Action for Cancer Therapy (PACT) was established by the IAEA in 2004 in response to the developing world's growing cancer crisis. It builds on previous IAEA experience in radiation medicine and technology - essential in cancer diagnosis and treatment - to assist LMCs cope with cancer by integrating radiotherapy into sustainable comprehensive cancer control programmes. An earlier IAEA publication, 'Setting Up a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects', describes how a radiotherapy centre should be developed, implemented and managed to establish a common and consistent framework in which all steps and procedures

  11. Biological Oceanography

    Science.gov (United States)

    Abbott, M. R.

    1984-01-01

    Within the framework of global biogeochemical cycles and ocean productivity, there are two areas that will be of particular interest to biological oceanography in the 1990s. The first is the mapping in space time of the biomass and productivity of phytoplankton in the world ocean. The second area is the coupling of biological and physical processes as it affects the distribution and growth rate of phytoplankton biomass. Certainly other areas will be of interest to biological oceanographers, but these two areas are amenable to observations from satellites. Temporal and spatial variability is a regular feature of marine ecosystems. The temporal and spatial variability of phytoplankton biomass and productivity which is ubiquitous at all time and space scales in the ocean must be characterized. Remote sensing from satellites addresses these problems with global observations of mesocale (2 to 20 days, 10 to 200 km) features over a long period of time.

  12. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P.; Bunker, Bruce C.; Huber, Dale L.

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  13. The biological effectiveness of antiproton irradiation

    DEFF Research Database (Denmark)

    Holzscheiter, Michael H.; Bassler, Niels; Agazaryan, Nzhde;

    2006-01-01

    Background and purpose: Antiprotons travel through tissue in a manner similar to that for protons until they reach the end of their range where they annihilate and deposit additional energy. This makes them potentially interesting for radiotherapy. The aim of this study was to conduct the first...... ever measurements of the biological effectiveness of antiprotons. Materials and methods: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7 MeV antiprotons, 48 MeV protons, or 60Co c-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose and...... particle fluence response relationships were constructed from data in the plateau and Bragg peak regions of the beams and used to assess the biological effectiveness. Results: Due to uncertainties in antiproton dosimetry we defined a new term, called the biologically effective dose ratio (BEDR), which...

  14. Radiotherapy for cutaneous cancers with xeroderma pigmentosum

    International Nuclear Information System (INIS)

    Purpose. - To analyze the therapeutic results of cutaneous cancers on xeroderma pigmentosum through a series of 15 patients treated by radiotherapy. Patients and methods. - Between 1993 and 2006, 15 patients with xeroderma pigmentosum and having cutaneous cancers were treated in the Radiotherapy Department of university hospital Habib-Bourguiba of Sfax in Tunisia. Seventy-three percent of the cases occurred in male patients and the mean age of appearance of the first tumour was 18.2 years. Tumour histology was squamous cell carcinoma in 74% of the cases. The total number of cutaneous tumours was 84. Ten patients had a surgical resection. Four patients did not respond to chemotherapy. The modality of irradiation was decided according to the size, thickness and localization of the tumour. The dose of radiotherapy was 60 Gy or equivalent with classic irradiation. Results. - The total number of lesions treated with radiotherapy was 64. Forty-three lesions were treated with contact-therapy, ten with brachytherapy and 11 with cobalt-therapy. The following acute complications were observed: cutaneous infection (53.3% of patients), radio-epithelitis (80% of patients) and necroses (33.3% of patients). Evaluation after treatment showed a clinical complete remission in 73% of the cases. Late effects were noted in seven cases: telangiectasia and cutaneous atrophy. A recurrence in the irradiated zone was observed in one case. A nodal metastasis was observed in two cases. Another patient presented lung metastases. After a median follow up of 37.2 months, four patients died, seven are alive with cutaneous cancer and four are alive with complete remission. Conclusion. - Radiotherapy is a possible and effective therapeutic alternative. Dose and methods are not defined for xeroderma pigmentosum. (authors)

  15. Experimental and clinical studies with intraoperative radiotherapy

    International Nuclear Information System (INIS)

    Studies of normal tissue tolerance to intraoperative radiotherapy were done upon 65 dogs subjected to laparotomy and 11 million electron volt electron irradiation in doses ranging from zero to 5,000 rads. Results of studies indicated that intact aorta and vena cava tolerate up to 5,000 rads without loss of structural integrity. Ureteral fibrosis and stenosis develop at doses of 3,000 rads or more. Arterial anastomoses heal after doses of 4,500 rads, but fibrosis can lead to occlusion. Intestinal suture lines heal after doses of 4,500 rads. Bile duct fibrosis and stenosis develop at doses of 2,000 rads or more. Biliary-enteric anastomoses fail to heal at any dose level. A clinical trial of intraoperative radiotherapy combined with radical surgery was performed upon 20 patients with advanced malignant tumors which were considered unlikely to be cured by conventional therapies and which included carcinomas of the stomach, carcinomas of the pancreas, carcinomas involving the hilus of the liver, retroperitoneal sarcomas and osteosarcomas of the pelvis. All patients underwent resection of gross tumor, followed by intraoperative irradiation of the tumor bed and regional nodal basins. Some patients received additional postoperative external beam radiotherapy. Treatment mortality for combined operation and radiotherapy occurred in four of 20 patients. Postoperative complications occurred in four of the 16 surviving patients. Local tumor control was achieved in 11 of the 16 surviving patients, with an over-all median follow-up period of 18 months. The clinical trial suggested that intraoperative radiotherapy is a feasible adjunct to resection in locally advanced tumors, that the resulting mortality and morbidity is similar to that expected from operation alone and that local tumor control may be improved

  16. Radical radiotherapy for T3 laryngeal cancers

    Energy Technology Data Exchange (ETDEWEB)

    Uno, T. [International Medical Center of Japan, Tokyo (Japan). Dept. of Radiation Therapy; Itami, J. [International Medical Center of Japan, Tokyo (Japan). Dept. of Radiation Therapy; Kotaka, K. [International Medical Center of Japan, Tokyo (Japan). Dept. of Radiation Therapy; Toriyama, M. [International Medical Center of Japan, Tokyo (Japan). Dept. of Otolaryngology

    1996-08-01

    From 1974 through 1992, 37 previously untreated patients with T3 laryngeal cancer (supraglottic 15, glottic 22) were treated with initial radical radiotherapy and surgery for salvage. Two-year local control rate with radiotherapy alone, ultimate voice preservation rate, and ultimate local control rate for T3 supraglottic cancer were 33%, 33%, and 60%, respectively. Corresponding figures for T3 glottic cancer were 32%, 23%, and 77%, respecitvely. Five-year cause-specific survival rate for T3 supraglottic cancer and glottic cancer were 47% and 77%, respectively. In T3 supraglottic cancer, none of the 4 patients with subglottic tumor extension attained local control by radiotherapy alone, and local-regional recurrence-free time were significantly shorter in patients with subglottic tumor extension or tracheostomy before radiotherapy. There were no serious late complications such as chondronecrosis, rupture of carotid artery attributed to radical radiotherapy, while 3 patients had severe laryngeal edema requiring total laryngectomy. (orig.) [Deutsch] Von 1974 bis 1992 wurden 37 zuvor nicht behandelte Patienten mit T3-Larynxkarzinomen (15 supraglottisch, 22 glottisch) primaer kurativ bestrahlt und, wenn erforderlich, einer Salvage-Operation unterzogen. Die Zwei-Jahres-Kontrollrate bei alleiniger Strahlentherapie, die Rate der Stimmerhaltung sowie die unter Einschluss der Operation erreichbare lokale Kontrollrate bei supraglottischen T3-Larynxkarzinomen betrugen 33%, 33% und 60%. Bei glottischen T3-Karzinomen wurden jeweils 32%, 23% und 77% erreicht. Die Fuenf-Jahres-Ueberlebensrate betrug 47% bei supraglottischen T3-Karzinomen und 77% bei den glottischen Karzinomen. Im Fall von supraglottischen Karzinomen erreichte keiner der vier Patienten mit subglottischer Tumorausdehnung eine lokale Kontrolle durch alleinige Strahlentherapie. Die lokoregionale rezidivfreie Zeit war bei den Patienten mit subglottischer Tumorausdehnung oder Tracheostomie vor Einleitung der

  17. Present status of radiotherapy in Zimbabwe

    International Nuclear Information System (INIS)

    Radiotherapy departments are one of the most expensive health facilities to equip, maintain and run efficiently. In Zimbabwe, there are two radiotherapy centres, at Parirenyatwa Central Hospital in Harare and at Mpilo Central Hospital in Bulawayo. Both these centres have nuclear imaging facilities. The radiotherapy services also cater for patients from neighbouring states. A referral system for consultation and prescription by the radiotherapist is in use. Administration of most cytotoxics is done in the radiotherapy department. Zimbabwe's population is over 8 million. Of this, yearly averages of 400 to 500 and over 700 new patients are seen at the Bulawayo and Harare centres respectively. So far 159 new cervical cancer patients have been seen this year at the Bulawayo centre. To cater for this and other malignancies, facilities ranging from the supervoltage therapy to a linear accelerator are available as well as limited brachytherapy facilities. The funding of these has been from the government, charity organisations and international aid agreements. Servicing and maintenance of the units is done by the private sector. Treatment planning is done mostly by radiographers but the more complex techniques are not done due to lack of qualified medical physicists. This shortage also affects the calibration of and other routine checks of the equipment. Progress in these services has been hampered by the lack of local radiotherapists. Improvements are expected with the WHO radiotherapist training programme due to start in 1990. If the cancer awareness programme is stepped up, the demands on the radiotherapy services will increase, necessitating review and updating of the present facilities and staffing levels. (author). 1 fig., 5 tabs

  18. The role of radiotherapy for thymic carcinoma

    International Nuclear Information System (INIS)

    The aim of this study is to evaluate retrospectively the role of radiotherapy for thymic carcinoma. Between 1973 and 1998, 14 patients with thymic carcinoma were treated at Gunma Prefectural Cancer Center. Two patients who had hematogenous metastasis were excluded from this study, therefore 12 patients were analyzed. The Masaoka staging system was used; four patients were diagnosed with stage III disease and eight patients with stage IV disease. The pathological subtype according to the World Health Organization histological criteria for thymic tumors was squamous cell carcinoma (low-grade histology) in six cases and undifferentiated carcinoma (high-grade histology) in six. Ten patients underwent thoracotomy, and two patients underwent excisional biopsy without thoracotomy. Ten patients (83%) received radiotherapy as a curative intent, and the median dose was 60 Gy. Systemic chemotherapy was administered to four patients (33%), and the majority (75%) of the regimens contained cisplatin. The 3-year overall survival rate was 25%. Histological subtype (low-grade versus high-grade), surgical resection (complete versus incomplete), radiotherapy and chemotherapy were evaluated as prognostic factors in a univariate analysis. Low-grade histology and complete resection were good prognostic factors, although these were not statistically significant. Patients who received radiotherapy had a better outcome than those who did not. The major sites of recurrence were the pleura and pericardium. Recurrence within the radiation field was observed in one of seven patients in whom failure patterns could be evaluated. Complete resection is mandatory if possible. Radiotherapy plays an important role in treating thymic carcinoma in terms of reducing local recurrence and prolonging survival time. Establishment of an innovative treatment protocol that includes chemotherapy is necessary to control intrathoracic relapse and distant metastasis. (authors)

  19. Evaluation of novel radiotherapy technologies: what evidence is needed to assess their clinical and cost effectiveness, and how should we get it?

    Science.gov (United States)

    van Loon, Judith; Grutters, Janneke; Macbeth, Fergus

    2012-04-01

    Technical innovations in radiation oncology--eg, intensity-modulated radiotherapy, stereotactic radiotherapy, and particle therapy--can be developed rapidly and introduced into the clinic even when costs associated with their use are much higher than those for conventional radiotherapy. Although clinical benefit is expected on the basis of superior biological and physical characteristics, data for clinical effectiveness of new radiotherapy techniques are scarce. Evidence from randomised clinical trials would be ideal but such studies focus mostly on new drugs. High investment costs and modifications over time make evaluation of novel radiotherapy technologies in clinical trials more complex. Here, we propose an algorithm for evaluation of the clinical and cost effectiveness of novel radiotherapy technologies. We suggest situations when randomised trials might be feasible and the type of trial that should be undertaken when they are not. Furthermore, we discuss the usefulness of dose-distribution models for estimation of expected clinical benefit and for selection of the patients' population with the highest expected benefit. Economic modelling, including the approach of real options analysis, can inform whether implementation of a technology should begin (based on available evidence) or be delayed (until further data are available), and it can indicate the best trial design and required sample size. PMID:22469127

  20. Biology and management of ependymomas.

    Science.gov (United States)

    Wu, Jing; Armstrong, Terri S; Gilbert, Mark R

    2016-07-01

    Ependymomas are rare primary tumors of the central nervous system in children and adults that comprise histologically similar but genetically distinct subgroups. The tumor biology is typically more associated with the site of origin rather than being age-specific. Genetically distinct subgroups have been identified by genomic studies based on locations in classic grade II and III ependymomas. They are supratentorial ependymomas with C11orf95-RELA fusion or YAP1 fusion, infratentorial ependymomas with or without a hypermethylated phenotype (CIMP), and spinal cord ependymomas. Myxopapillary ependymomas and subependymomas have different biology than ependymomas with typical WHO grade II or III histology. Surgery and radiotherapy are the mainstays of treatment, while the role of chemotherapy has not yet been established. An in-depth understanding of tumor biology, developing reliable animal models that accurately reflect tumor molecule features, and high throughput drug screening are essential for developing new therapies. Collaborative efforts between scientists, physicians, and advocacy groups will enhance the translation of laboratory findings into clinical trials. Improvements in disease control underscore the need to incorporate assessment and management of patients' symptoms to ensure that treatment advances translate into improvement in quality of life. PMID:27022130

  1. Randomised trial of standard 2D radiotherapy (RT) versus intensity modulated radiotherapy (IMRT) in patients prescribed breast radiotherapy

    International Nuclear Information System (INIS)

    Background: Radiation dose distributions created by two dimensional (2D) treatment planning are responsible for partial volumes receiving >107% of the prescribed dose in a proportion of patients prescribed whole breast radiotherapy after tumour excision of early breast cancer. These may contribute to clinically significant late radiation adverse effects. Aim: To test three dimensional (3D) intensity modulated radiotherapy (IMRT) against 2D dosimetry using standard wedge compensators in terms of late adverse effects after whole breast radiotherapy. Methods: Three hundred and six women prescribed whole breast radiotherapy after tumour excision for early stage cancer were randomised to 3D IMRT (test arm) or 2D radiotherapy delivered using standard wedge compensators (control arm). All patients were treated with 6 or 10 MV photons to a dose of 50 Gy in 25 fractions to 100% in 5 weeks followed by an electron boost to the tumour bed of 11.1 Gy in 5 fractions to 100%. The primary endpoint was change in breast appearance scored from serial photographs taken before radiotherapy and at 1, 2 and 5 years follow up. Secondary endpoints included patient self-assessments of breast discomfort, breast hardness, quality of life and physician assessments of breast induration. Analysis was by intention to treat. Results: 240 (79%) patients with 5-year photographs were available for analysis. Change in breast appearance was identified in 71/122 (58%) allocated standard 2D treatment compared to only 47/118 (40%) patients allocated 3D IMRT. The control arm patients were 1.7 times more likely to have a change in breast appearance than the IMRT arm patients after adjustment for year of photographic assessment (95% confidence interval 1.2-2.5, p = 0.008). Significantly fewer patients in the 3D IMRT group developed palpable induration assessed clinically in the centre of the breast, pectoral fold, infra-mammary fold and at the boost site. No significant differences between treatment groups

  2. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  3. Biology Notes.

    Science.gov (United States)

    School Science Review, 1983

    1983-01-01

    Describes laboratory procedures, demonstrations, and classroom activities/materials, including water relation exercise on auxin-treated artichoke tuber tissue; aerobic respiration in yeast; an improved potometer; use of mobiles in biological classification, and experiments on powdery mildews and banana polyphenol oxidase. Includes reading lists…

  4. Overview of radiotherapy resources in Beijing in 2010

    International Nuclear Information System (INIS)

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

  5. Psychological and physical distress of cancer patients during radiotherapy

    International Nuclear Information System (INIS)

    Purpose: patients undergoing radiotherapy have physical and psychological symptoms related to the underlying disease and the treatment. In order to give the best possible support to the patients, more knowledge about the amount and the changing of distress in the course of radiotherapy is of essentially importance. Methods: The distress was measured in a consecutive sample of cancer patients (n=82) undergoing radiotherapy. Each patient was given the EORTC-QLQ-C30, the HADS and a special questionnaire which ascertain radiotherapy-specific items before starting the radiotherapy, at the onset of radiotherapy, in the third week of radiotherapy and 3 weeks after the end of radiotherapy. Results: within the first week of treatment the psychological distress of the patients is increasing; 98.8 % of the patients are 'moderate distressed', 46 % 'severe distressed'. General physical symptoms seem not to be affected by the radiotherapy, there is no changing. The distress caused by the organization of the radiotherapy is decreasing, while therapy-related symptoms are increasing in the course of radiotherapy. Even after the end of the therapy these symptoms keep on causing distress, sometimes in a higher amount than before. A correlation between sex, sort of cancer and curative or palliative treatment and the amount of distress was found. Conclusion: the results stress the importance of adequate emotional support for patients undergoing radiotherapy especially in the first week of treatment and after the treatment. There is a need for the development of a valid radiotherapy - questionnaire in order to be able to measure the distress of these patients. (author)

  6. Radiotherapy-induced plasticity of prostate cancer mobilizes stem-like non-adherent, Erk signaling-dependent cells

    Czech Academy of Sciences Publication Activity Database

    Kyjacová, Lenka; Hubáčková, Soňa; Krejčíková, Kateřina; Strauss, R; Hanzlíková, Hana; Dzijak, Rastislav; Imrichová, Terezie; Šímová, Jana; Reiniš, Milan; Bartek, Jiří; Hodný, Zdeněk

    -, July (2014). ISSN 1350-9047 R&D Projects: GA ČR GA13-17658S; GA MZd NT14461 Grant ostatní: Danish Research Council(DK) DFF-1331-00262B; Lundbeck Foundation(DK) (R93-A8990; European Commission DDResponse 259893 Institutional support: RVO:68378050 Keywords : Radiotherapy * induced plasticity * prostate cancer * Erk Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.184, year: 2014

  7. A detrimental effect of a combined chemotherapy-radiotherapy approach in children with diffuse intrinsic brain stem gliomas?

    International Nuclear Information System (INIS)

    Purpose: To compare the proportion of patients that survive at least 1 year following treatment with hyperfractionated radiotherapy (HRT) to a dose of 70.2 Gy on Pediatric Oncology Group (POG) study no. 8495 with that of patients treated with similar radiotherapy plus cisplatinum given by continuous infusion on weeks 1, 3, and 5 of radiotherapy on POG no. 9239. Methods and Materials: The eligibility criteria for the two studies were identical and included age 3 to 21 years, previously untreated tumor involving the brain stem of which two-thirds was in the pons, history less than 6 months, and clinical findings typical for diffuse intrinsic brain stem glioma, including cranial nerve deficits, long tract signs, and ataxia. The outcome of 57 patients who were treated at the 70.2 Gy dose level of POG no. 8495 between May 1986 and February 1988 was compared with that of 64 patients treated with identical radiotherapy plus cisplatinum on POG no. 9239 between June 1992 and March 1996. Results: The number of patients accrued to POG no. 9239 was determined to guarantee that the probability was at least 0.80 of correctly detecting that the 1-year survival rate exceeded that of patients on POG no. 8495 by 0.2. However, the z value for this test was -1.564, giving a p value of 0.9411. That is, there is almost sufficient evidence to conclude that survival for patients receiving HRT plus cisplatinum on POG no. 9239 was worse than that for patients receiving the same radiotherapy alone on POG no. 8495. Conclusion: The finding that patients who received cisplatinum given as a radiosensitizing agent concurrent with HRT fared less well than those receiving the same dose of HRT alone was unexpected and is clearly a cause for concern as many current protocols for patients with diffuse intrinsic brain stem gliomas call for use of chemotherapeutic and/or biological agents given concurrent with radiotherapy

  8. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    Energy Technology Data Exchange (ETDEWEB)

    Macknelly, Andrew [Norfolk and Norwich University Hospital (United Kingdom); Day, Jane [Faculty of Health, Wellbeing and Science, University Campus Suffolk, Waterfront Building, Neptune Quay, Ipswich (United Kingdom)], E-mail: j.day@ucs.ac.uk

    2009-11-15

    ? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504, Braam P, Terhaard C, Roesnink J, Cornelis P, Raaijmakers C. Intensity-modulated radiotherapy significantly reduces xerostomia compared with conventional radiotherapy. International Journal of Radiation Oncology, Biology and Physics 2006, Wendt TG, Abbasi-Senger N, Salz H, Pinquart I, Koscelny S, Przetak S, et al. 3D-conformal-intensity modulated radiotherapy with compensators for head and neck cancer: clinical results of normal tissue sparing. Radiation Oncology 2006;1:18. Available from: (http://www.ro-journal.com/content/1/1/18) [accessed on 21.11.06].]. This, in turn, offers increased normal tissue sparing than conventional radiotherapy [Ng M, Porceddu S, Milner A, Corry J, Hornby C, Hope G, et al. Parotid-sparing radiotherapy: does it really reduce xerostomia? Clinical Oncology 2005;17(8):610-7.]. The survey indicated that all three techniques, however, are still in use in oncology and radiotherapy departments, and several departments stated that financial considerations were hindering their move toward providing IMRT.

  9. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    International Nuclear Information System (INIS)

    ? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504, Braam P, Terhaard C, Roesnink J, Cornelis P, Raaijmakers C. Intensity-modulated radiotherapy significantly reduces xerostomia compared with conventional radiotherapy. International Journal of Radiation Oncology, Biology and Physics 2006, Wendt TG, Abbasi-Senger N, Salz H, Pinquart I, Koscelny S, Przetak S, et al. 3D-conformal-intensity modulated radiotherapy with compensators for head and neck cancer: clinical results of normal tissue sparing. Radiation Oncology 2006;1:18. Available from: (http://www.ro-journal.com/content/1/1/18) [accessed on 21.11.06].]. This, in turn, offers increased normal tissue sparing than conventional radiotherapy [Ng M, Porceddu S, Milner A, Corry J, Hornby C, Hope G, et al. Parotid-sparing radiotherapy: does it really reduce xerostomia? Clinical Oncology 2005;17(8):610-7.]. The survey indicated that all three techniques, however, are still in use in oncology and radiotherapy departments, and several departments stated that financial considerations were hindering their move toward providing IMRT.

  10. Biological imaging in radiation therapy: role of positron emission tomography

    International Nuclear Information System (INIS)

    In radiation therapy (RT), staging, treatment planning, monitoring and evaluation of response are traditionally based on computed tomography (CT) and magnetic resonance imaging (MRI). These radiological investigations have the significant advantage to show the anatomy with a high resolution, being also called anatomical imaging. In recent years, so called biological imaging methods which visualize metabolic pathways have been developed. These methods offer complementary imaging of various aspects of tumour biology. To date, the most prominent biological imaging system in use is positron emission tomography (PET), whose diagnostic properties have clinically been evaluated for years. The aim of this review is to discuss the valences and implications of PET in RT. We will focus our evaluation on the following topics: the role of biological imaging for tumour tissue detection/delineation of the gross tumour volume (GTV) and for the visualization of heterogeneous tumour biology. We will discuss the role of fluorodeoxyglucose-PET in lung and head and neck cancer and the impact of amino acids (AA)-PET in target volume delineation of brain gliomas. Furthermore, we summarize the data of the literature about tumour hypoxia and proliferation visualized by PET. We conclude that, regarding treatment planning in radiotherapy, PET offers advantages in terms of tumour delineation and the description of biological processes. However, to define the real impact of biological imaging on clinical outcome after radiotherapy, further experimental, clinical and cost/benefit analyses are required. (topical review)

  11. Preoperative radiotherapy of maxillary sinus cancer

    International Nuclear Information System (INIS)

    This study was to evaluate the effectiveness of preoperative radiotherapy in maxillary sinus cancer. A retrospective analysis was done for 42 patients with maxillary sinus cancer who were treated with radiation with or without surgery from April 1986 to September 1996. There were 27 male and 15 female patients. Patients' age ranged from 24 to 75 years (median 56 years). Stage distribution showed 2 in T2, 19 in T3, and 21 in T4 lesions. The histologic type was squamous cell carcinoma in 38, undifferentiated carcinoma in 1, transitional cell carcinoma in 1, and adenoid cystic carcinoma in 2 patients, All patients were treated with radiation initially with a dosage range of 50.4-70.2 Gy (median 70.2 Gy) before further evaluation of remnant disease. Eleven patients were given induction chemotherapy (2 cycles of 5-fluorouracil and cisplatin) concurrently with radiotherapy. Six to eight weeks after radiotherapy with or without chemotherapy, computerized tomography (CT) of paranasal sinus was taken to evaluate remnant disease. If the CT finding showed remnant disease, a Caldwell-Luc procedure was done to get the specimen of suspicious lesions. A radical maxillectomy was done if the specimen was proven to contain malignancy. In contrast periodic follow-up examination was done without any radical surgery if the tissue showed only granulation tissue. Follow-up period ranged from 3 to 92 months with a median 16 months. Nine (21.4%) patients showed complete response (CR) and 33 patients (78.6%) showed persistent disease (PER) to initial radiotherapy. Among the 9 CR patients, 7 patients had no evidence of disease (NED), 1 patient had local failure, and 1 patient had regional failure. Among 33 PER patients, salvage total maxillectomy was done in 10 patients, and the surgery was not feasible or refused in 23 patients. Following the salvage radical surgery, 2 patients were NED and 8 patients were PER status. Overall and disease- free survival rate at 5 years was 23.1% and 16

  12. Role of bio-effect models in improving radiotherapy of cancer

    International Nuclear Information System (INIS)

    Application of linear quadratic model of cell survival in radiotherapy has enabled to successfully predict the response of both the normal tissues and tumours. Even the simplest form of BED (biological effective dose) equation for fractionated radiotherapy could precisely predict the late normal tissue complications resulting from large dose per fraction. These observations have led to the development MFD (multiple fractions daily) protocol, with the specific objective of reducing late normal tissue morbidity. Protraction of treatment and consequent loss of BED and tumour control; multiple fractions delivered without adequate intervals resulting in incomplete repair of sub-lethal damage and consequent normal tissue complications, have been explained successfully by the LQ model. In the recent past LDR (low dose rate) brachytherapy is mostly replaced by HDR (high dose rate) technique. A series of calculations based on tumour bio-kinetics parameters, as well as the geometric sparing provides a sound rationale for replacing LDR technique by HDR technique. Some of the calculations relevant to this will be presented during this talk. Bio-effect models can also provide insight in to the rationale of RIT (radio-immunotherapy). With an adequate knowledge of biological half-life of antibodies in the tumour/critical organs, and biological uptake half-time in the tumour, it is possible to evaluate the efficacy of a number of radio-nuclides in RIT. Calculations based on LQ models suggest that longer lived isotopes such as 32P, 86Rb, 144mIn may have an advantage over the shorter lived radio-nuclides. A clear knowledge of the various parameters like/values, potentially doubling time of tumour and other bio-kinetic parameters may hold the key for successful application of bio-effect models in predicting the response to radiotherapy. Feedback from the clinics will further help in refining and validating the existing models. (author)

  13. Image-guided radiotherapy (IGRT) and four dimensional radiotherapy (4DRT)

    International Nuclear Information System (INIS)

    Since the development of conformation radiotherapy in the 1960s by Takahashi, et al., diagnostic and localization accuracy have been the main concerns. With increasing improvement in imaging techniques and multileaf collimators, three dimensional conformal radiotherapy (3D CRT) and intensity modulated radiotherapy (IMRT) have prevailed to produce highly conformal dose distribution. Image guided radiotherapy (IGRT), in which diagnostic imaging techniques are equipped in the treatment room, has been paid more attention than before to increase localization accuracy in the use of complex fields in clinical radiotherapy. Setup error has been shown to be reduced by using stereotactic frames for intracranial diseases, diagnostic X ray imagers, ultrasound, or computed tomography in the treatment room for relatively static organs. Planning target volume (PTV) margin for the clinical target volume (CTV) can be reduced by using these IGRT techniques. However, for mobile tumours such as those in the liver or lung, it is still difficult to use a 'tight' margin because of difficulty focusing radiation beams exactly on the moving tumour. Planning target volume for these mobile or moving tumours has generally been determined with a large PTV margin in the direction of tumour movement. A respiration gated radiotherapy system was developed in an attempt to reduce the PTV margin. However, it remained impossible to neglect the possibility that the tumour might be dislocated by depth of breath or setup error. A more accurate method is required to determine the 3D coordinates of a moving tumour during radiotherapy. The relative relationship between the tumour and the surrounding normal structure may change due to tumour mobility, thus a more accurate treatment planning method is also required accounting for temporal changes of anatomy. We have developed a linear accelerator synchronized with a fluoroscopic real time tumour tracking radiotherapy system (RTRT) by which the 3D location of

  14. Efficacy of gamma knife stereotactic radiotherapy and whole-brain radiotherapy in treatment of brain metastases

    International Nuclear Information System (INIS)

    Objective: To analyze the efficacy and prognosis of stereotactic radiotherapy (SRT) and whole-brain radiotherapy (WBRT) in treatment of brain metastases, and to observe the influence of temozolomide (TMZ) on survival rate during the period of radiotherapy. Methods: A total of 52 patients with brain metastases were divided into two groups according to treatment methods,including 35 patients treated with WBRT plus SRT and 17 patients treated with SRT alone. WBRT dose was 1.8 - 3.0 Gy per fraction, one fraction a day, five fractions per week, with total dose of 30 - 40 Gy. After WBRT, gamma knife was performed with prescription isodose line of 45%-70% surrounding the planned target volume in WBRT + SRT group. The marginal dose was 12-15 Gy and the center dose was 20-30 Gy. In SRT group, the prescription isodose line was 45%-70% and the marginal dose was 36-40 Gy while the center up to 70-80 Gy. The follow up time was 1-2 years. Besides 20 patients in this study took temozolomide capsule during and after radiotherapy. The schedule of concomitant chemotherapy was temozolomide of 75 mg/m2 by oral administration every day until radiotherapy was over, and then temozolomide of 150 mg/m2 was taken for 3-6 months after radiotherapy. Results: The efficiency during 1-3 months after treatment was 84.62% in this study. In the WBRT + SRT group, the efficiency was 88.57% and declined to 76.47% in the SRT group. The six month-and one year-local control rate were 92.10% and 85.20%, respectively. The average survival time of WBRT + SRT was 13.2 months and median survival time was 11 months.Six month-, one year- and eighteen months-survival rate were 71.40%, 54.30% and 14.30%, respectively. In the SRT group, the average survival time was 10.2 months and median survival time was 9 months. Six month-, one year- and eighteen month-survival rate were 41.20%, 23.50% and 5.88%, respectively, while those for RT + TMZ group were 80.00%, 60.00% and 10.00%. In comparison, those in RT group were

  15. Investigation of anxiety about radiotherapy and development of the Categorical Anxiety Scale about Radiotherapy

    International Nuclear Information System (INIS)

    There are many patients with anxiety for radiotherapy though it is one of most important treatments for cancer, to which attention has not been fully paid. Authors investigated this anxiety to classify and quantitatively evaluate the problems. Firstly they asked 48 patients with various cancers about the concrete anxiety items related with radiotherapy, and the items were examined by the expert doctor of consultation-liaison psychiatry and of radiology to make up questions of 25 items about radiotherapy. Then those questions together with Hospital Anxiety and Depression Scale (HAD) were asked to in-(52 subjects) and out-(133) patients (106 males and 79 females of the mean age 62.58 years) to classify anxiety and to see the reliability and validity of items included. Factor analysis of the results revealed that three kinds of anxiety, i.e., adverse effects of radiation, environments at irradiation and effect of radiotherapy, were significant. Based on this, authors arranged the Categorical Anxiety Scale about Radiotherapy composed from 17 items, of which reliability and validity in contents and in parallelism with HAD had been assured. (T.I.)

  16. Contribution of radiotherapy to the treatment of malignant tumors, 3. Combined drugs and radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Niibe, Hideo; Takahashi, Iku; Tamaki, Yoshio (Gunma Univ., Maebashi (Japan). School of Medicine)

    1984-09-01

    Effects of cytotoxic agent, hormone, hypoxic cell sensitizer, and radiation protector combined with radiation therapy in cancer management were analysed. The results were as follows: 1) An increase in response was seen in 25% or more of tumor nodules given radiotherapy combined with misonidazole, anoxic cell sensitizer, compared with radiotherpy alone. But the drug was also found to be neurotoxic and peripheral neuropathy. 2) Evidence has been given that Amifostine may protect the mucosal damage from radiation when Amifostine prior to irradiation was administrated to patients with tumor in the head and neck or in the pelvis. 3) There were no difference between five year survival of radiotherapy alone and with chemotherapy for patients with stage I Non-Hodgkin lymphoma. Chemotherapy following radiotherapy for patients with stage II was more effective treatment method than radiotherapy alone. 4) Radiotherapy for patients with prostate cancer was performed to control only primary site. The success rates of local control were over 80%. The near future holds extensive promise for a combination of radiation therapy, cytotoxic chemotherapy, hormone therapy, hypoxic cell sensitizer, and radiation protectors. All of these when used in the appropriate circumstances may yield significant improvements in the therapeutic ratio and in the long-tern control of tumors.

  17. South Asian Medicinal Compounds as Modulators of Resistance to Chemotherapy and Radiotherapy

    Directory of Open Access Journals (Sweden)

    N. Rajendra Prasad

    2016-03-01

    Full Text Available Cancer is a hyperproliferative disorder that involves transformation, dysregulation of apoptosis, proliferation, invasion, angiogenesis and metastasis. During the last 30 years, extensive research has revealed much about the biology of cancer. Chemotherapy and radiotherapy are the mainstays of cancer treatment, particularly for patients who do not respond to surgical resection. However, cancer treatment with drugs or radiation is seriously limited by chemoresistance and radioresistance. Various approaches and strategies are employed to overcome resistance to chemotherapy and radiation treatment. Many plant-derived phytochemicals have been investigated for their chemo- and radio-sensitizing properties. The peoples of South Asian countries such as India, Pakistan, Sri Lanka, Nepal, Bangladesh and Bhutan have a large number of medicinal plants from which they produce various pharmacologically potent secondary metabolites. The medicinal properties of these compounds have been extensively investigated and many of them have been found to sensitize cancer cells to chemo- and radio-therapy. This review focuses on the role of South Asian medicinal compounds in chemo- and radio-sensitizing properties in drug- and radio-resistant cancer cells. Also discussed is the role of South Asian medicinal plants in protecting normal cells from radiation, which may be useful during radiotherapy of tumors to spare surrounding normal cells.

  18. South Asian Medicinal Compounds as Modulators of Resistance to Chemotherapy and Radiotherapy.

    Science.gov (United States)

    Prasad, N Rajendra; Muthusamy, Ganesan; Shanmugam, Mohana; Ambudkar, Suresh V

    2016-01-01

    Cancer is a hyperproliferative disorder that involves transformation, dysregulation of apoptosis, proliferation, invasion, angiogenesis and metastasis. During the last 30 years, extensive research has revealed much about the biology of cancer. Chemotherapy and radiotherapy are the mainstays of cancer treatment, particularly for patients who do not respond to surgical resection. However, cancer treatment with drugs or radiation is seriously limited by chemoresistance and radioresistance. Various approaches and strategies are employed to overcome resistance to chemotherapy and radiation treatment. Many plant-derived phytochemicals have been investigated for their chemo- and radio-sensitizing properties. The peoples of South Asian countries such as India, Pakistan, Sri Lanka, Nepal, Bangladesh and Bhutan have a large number of medicinal plants from which they produce various pharmacologically potent secondary metabolites. The medicinal properties of these compounds have been extensively investigated and many of them have been found to sensitize cancer cells to chemo- and radio-therapy. This review focuses on the role of South Asian medicinal compounds in chemo- and radio-sensitizing properties in drug- and radio-resistant cancer cells. Also discussed is the role of South Asian medicinal plants in protecting normal cells from radiation, which may be useful during radiotherapy of tumors to spare surrounding normal cells. PMID:26959063

  19. Proton Radiotherapy for Pediatric Ewing’s Sarcoma: Initial Clinical Outcomes

    International Nuclear Information System (INIS)

    Purpose: Proton radiotherapy (PT) has been prescribed similarly to photon radiotherapy to achieve comparable disease control rates at comparable doses. The chief advantage of protons in this setting is to reduce acute and late toxicities by decreasing the amount of normal tissue irradiated. We report the preliminary clinical outcomes including late effects on our pediatric Ewing’s sarcoma patients treated with PT at the Francis H. Burr Proton Therapy Center at Massachusetts General Hospital (Boston, MA). Methods and Materials: This was a retrospective review of the medical records of 30 children with Ewing’s sarcoma who were treated with PT between April 2003 and April 2009. Results: A total of 14 male and 16 female patients with tumors in several anatomic sites were treated with PT at a median age of 10 years. The median dose was 54 Gy (relative biological effectiveness) with a median follow-up of 38.4 months. The 3-year actuarial rates of event-free survival, local control, and overall survival were 60%, 86%, and 89%, respectively. PT was acutely well tolerated, with mostly mild-to-moderate skin reactions. At the time of writing, the only serious late effects have been four hematologic malignancies, which are known risks of topoisomerase and anthracyline exposure. Conclusions: Proton radiotherapy was well tolerated, with few adverse events. Longer follow-up is needed to more fully assess tumor control and late effects, but the preliminary results are encouraging.

  20. Rise and fall of hypofractionation in clinical radiotherapy in the 20th century

    International Nuclear Information System (INIS)

    The purpose of this article is to review of the use of hypofractionated radiotherapy during the last two centuries. We define hypofractionation as any treatment where the individual fraction exceeds 2.0 Gray (Gy). The number of fractions is disregarded. The struggle of the early radiotherapists, the slow acceptance of fractionation, and the battle between the German and the French schools are reviewed. The early mathematical formulae of biological effects radiation are described and commented on. The paramount contribution in radiotherapy by British scientists gave rise to a new science: radiobiology. This branch had now matured into an exact discipline, separate from, and yet utterly depending on, its 100 years old sibling: Diagnostic Radiology. The come-back and fall of hypofractionation during two centuries is described, and set in relation to the treatment philosophy of the corresponding period. Injuries are described, and the long latency period for late reactions pointed out. Some of the legal aspects of the injuries are discussed. The come-back of hypofractionation - twice declared dead and buried the 20th century - in the late 1990's is explained. The brilliant incorporation variability (α andβ) into mathematical exactness (the LQ-formula) has had, and will have a profound impact on clinical radiotherapy. (author)

  1. Mesoscopic biology

    Indian Academy of Sciences (India)

    G V Shivashankar

    2002-02-01

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological systems. In recent years advances in technology have led to the study of some of the design principles of these machines; in particular at the level of an individual molecule. For example, the forces that operate in molecular interactions, the stochasticity involved in these interactions and their spatio-temporal dynamics are beginning to be explored. Understanding such design principles is opening new possibilities in mesoscopic physics with potential applications.

  2. Biological programming

    OpenAIRE

    Ramsden, Jeremy J.; Bándi, Gergely

    2010-01-01

    Biology offers a tremendous set of concepts that are potentially very powerfully usable for the software engineer, but they have been barely exploited hitherto. In this position paper we propose a fresh attempt to create the building blocks of a programming technology that could be as successful as life. A key guiding principle is to develop and make use of unambiguous definitions of the essential features of life.

  3. Biological radioprotector

    International Nuclear Information System (INIS)

    According to the patent description, the biological radioprotector is deuterium depleted water, DDW, produced by vacuum distillation with an isotopic content lower than natural value. It appears as such or in a mixture with natural water and carbon dioxide. It can be used for preventing and reducing the ionizing radiation effects upon humans or animal organisms, exposed therapeutically, professionally or accidentally to radiation. The most significant advantage of using DDW as biological radioprotector results from its way of administration. Indeed no one of the radioprotectors currently used today can be orally administrated, what reduces the patients' compliance to prophylactic administrations. The biological radioprotector is an unnoxious product obtained from natural water, which can be administrated as food additive instead of drinking water. Dose modification factor is according to initial estimates around 1.9, what is a remarkable feature when one takes into account that the product is toxicity-free and side effect-free and can be administrated prophylactically as a food additive. A net radioprotective action of the deuterium depletion was evidenced experimentally in laboratory animals (rats) hydrated with DDW of 30 ppm D/(D+H) concentration as compared with normally hydrated control animals. Knowing the effects of irradiation and mechanisms of the acute radiation disease as well as the effects of administration of radiomimetic chemicals upon cellular lines of fast cell division, it appears that the effects of administrating DDW result from stimulation of the immunity system. In conclusion, the biological radioprotector DDW presents the following advantages: - it is obtained from natural products without toxicity; - it is easy to be administrated as a food additive, replacing the drinking water; - besides radioprotective effects, the product has also immunostimulative and antitumoral effects

  4. Preparation and preclinical evaluation of 211At-labelled compounds for α-particle radiotherapy

    International Nuclear Information System (INIS)

    The interest for α-particle emitters in internal radiotherapy is increasing due to improved conjugation chemistry. Experimental work has concentrated on 211At and 212Bi since these to nuclides have radiochemical and physical properties suitable for medical application. In this report it is demonstrated that biologically active 211At-labelled compounds can be prepared within a relatively short time allowing utilization of this 7.2 h α-particle. It is further shown that 211At-TP-3 treatment of human osteosarcoma in vitro gives promising therapeutic ratios. 76 refs., 5 figs., 3 tabs

  5. Preparation and preclinical evaluation of {sup 211}At-labelled compounds for {alpha}-particle radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, R.H.

    1994-12-31

    The interest for {alpha}-particle emitters in internal radiotherapy is increasing due to improved conjugation chemistry. Experimental work has concentrated on {sup 211}At and {sup 212}Bi since these to nuclides have radiochemical and physical properties suitable for medical application. In this report it is demonstrated that biologically active {sup 211}At-labelled compounds can be prepared within a relatively short time allowing utilization of this 7.2 h {alpha}-particle. It is further shown that {sup 211}At-TP-3 treatment of human osteosarcoma in vitro gives promising therapeutic ratios. 76 refs., 5 figs., 3 tabs.

  6. Mutant frequency of radiotherapy technicians appears to be associated with recent dose of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Messing, K.; Ferraris, J.; Bradley, W.E.; Swartz, J.; Seifert, A.M. (Universite du Quebec a Montreal (Canada))

    1989-10-01

    The frequency of hypoxanthine phosphoribosyl transferase (HPRT) mutants among peripheral T-lymphocytes of radiotherapy technicians primarily exposed to 60Co was measured by the T-cell cloning method. Mutant frequencies of these technicians in 1984 and 1986 were significantly higher than those of physiotherapy technicians who worked in a neighboring service, and correlated significantly with thermoluminescence dosimeter readings recorded during the 6 mo preceding mutant frequency determination. Correlations decreased when related to dose recorded over longer time intervals. HPRT mutant frequency determination in peripheral lymphocytes is a good measure of recently received biologically effective radiation dose in an occupationally exposed population.

  7. The first French randomized prospective study of the economic and medical benefit of carbon ion radiotherapy

    International Nuclear Information System (INIS)

    Carbon ion therapy is an innovative radiotherapy modality for non-operable radio-resistant or resected cancers. Its efficiency is due to improved ballistic accuracy and biological efficiency. The authors present the first phase III study of carbon ion therapy in France. This technique concerns some sarcomas and adenoid cystic carcinomas of head and neck. The authors indicate the possible treatment procedures (doses, sessions) for the different types of cancers, and how the study is to be performed (number of patients, randomization, and multicentre approach). Short communication

  8. Inorganic chemistry in nuclear imaging and radiotherapy. Current and future directions

    International Nuclear Information System (INIS)

    Radiometals play an important role in diagnostic and therapeutic radiopharmaceuticals. This field of radiochemistry is multidisciplinary, involving radiometal production, separation of the radiometal from its target, chelate design for complexing the radiometal in a biologically stable environment, specific targeting of the radiometal to its in vivo site, and nuclear imaging and/or radiotherapy applications of the resultant radiopharmaceutical. The critical importance of inorganic chemistry in the design and application of radiometal-containing imaging and therapy agents is described from a historical perspective to future directions. (orig.)

  9. Predictive factors for the response of pulmonary tumours treated by robotic stereotactic radiotherapy

    International Nuclear Information System (INIS)

    The authors report a study which aimed at identifying factors influencing the response to radiotherapy performed in robotic stereotactic conditions with CyberKnife within the frame of treatment of primitive or secondary pulmonary tumours. Thirty eight stage I cancers, 22 metastases including 17 epidermoid carcinomas, and 43 adenocarcinomas have been treated this way. The analysis of data and results reveals that feminine gender, a biological dose greater than 140 Gy, and an age greater than 65 year old are associated with a better tumour response. Short communication

  10. Telemedicine in radiotherapy treatment planning: requirements and applications

    International Nuclear Information System (INIS)

    Telemedicine facilitates decentralized radiotherapy services by allowing remote treatment planning and quality assurance of treatment delivery. A prerequisite is digital storage of relevant data and an efficient and reliable telecommunication system between satellite units and the main radiotherapy clinic. The requirements of a telemedicine system in radiotherapy is influenced by the level of support needed. In this paper we differentiate between three categories of telemedicine support in radiotherapy. Level 1 features video conferencing and display of radiotherapy images and dose plans. Level 2 involves replication of selected data from the radiotherapy database - facilitating remote treatment planning and evaluation. Level 3 includes real-time, remote operations, e.g. target volume delineation and treatment planning performed by the team at the satellite unit under supervision and guidance from more experienced colleagues at the main clinic. (author)

  11. Marine biology

    International Nuclear Information System (INIS)

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  12. Marine biology

    Energy Technology Data Exchange (ETDEWEB)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.

  13. [How to maximize skin care during radiotherapy?].

    Science.gov (United States)

    Fromantin, I; Lesport, G; Le Mée, M

    2015-10-01

    No consensual guidelines exist regarding the management of early effects of radiotherapy. But preventive and curative care strategies could be adapted in the aim to delay erythema, limit complications and improve patients' comfort. Prevention involves encouraging patients to take care of their skin, avoid moisture, frictions, sun exposition and dry soap. When these rules seem insufficient, products (dressings, solution, or cream) could be prescribed, according to the individual risk of each patient. Preventive measures are accentuated when radiodermatitis appears and/or topics indicated for wound healing could be applied. Care (education, dressing, observation) needs a multidisciplinary approach. Improvements of radiotherapy treatments (methods, techniques) have been the most effective evolution on radiodermatitis. PMID:26344433

  14. Radical radiotherapy for carcinoma of the vulva

    Energy Technology Data Exchange (ETDEWEB)

    Slevin, N.J.; Pointon, R.C.S.

    1989-02-01

    A study was made of 58 patients with carcinoma of the vulva treated by radical radiotherapy between 1965 and 1982. The choice of treatment technique was influenced by site and extent of disease as well as the general condition of the patient. The crude 5-year survival was 26% (15/58). Local control was achieved in 40% of cases and was associated with tumour size of 4 cm or less. Radionecrosis occurred in nine cases but none of these required surgical intervention. Surgery remains the treatment of choice for carcinoma of the vulva. This report emphasizes that radical radiotherapy has a curative potential in those cases considered unsuitable for surgery and that the necrosis type and rate are within the limits of acceptable morbidity.

  15. Radical radiotherapy for carcinoma of the vulva

    International Nuclear Information System (INIS)

    A study was made of 58 patients with carcinoma of the vulva treated by radical radiotherapy between 1965 and 1982. The choice of treatment technique was influenced by site and extent of disease as well as the general condition of the patient. The crude 5-year survival was 26% (15/58). Local control was achieved in 40% of cases and was associated with tumour size of 4 cm or less. Radionecrosis occurred in nine cases but none of these required surgical intervention. Surgery remains the treatment of choice for carcinoma of the vulva. This report emphasizes that radical radiotherapy has a curative potential in those cases considered unsuitable for surgery and that the necrosis type and rate are within the limits of acceptable morbidity. (author)

  16. Voice change after radiotherapy: some preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Colton, R.H.; Sagerman, R.H.; Chung, C.T.; Yu, Y.W.; Reed, G.F.

    1978-06-01

    A one-third octave spectral analysis was performed on two sentences spoken by 5 patients with laryngeal cancer, 5 with head/neck cancer not involving the vocal cords, and 12 normal subjects. Recordings were made prior to and at weekly intervals during radiotherapy as well as at periodic intervals post-treatment. Patients with laryngeal cancer exhibited lower spectral levels than normal throughout radiotherapy as well as several months post-treatment. By one year after treatment, the spectral levels of these patients were largely in the normal range. Patients with head/neck cancer not involving the vocal cords exhibited greater than normal sound pressure levels throughout most of the spectrum. These levels remained high even at one month post-treatment. Irradiation of normal vocal cord tissue also seems to result in higher spectral levels.

  17. Complications of surgery for radiotherapy skin damage

    International Nuclear Information System (INIS)

    Complications of modern surgery for radiotherapy skin damage reviewed in 28 patients who had 42 operations. Thin split-thickness skin grafts for ulcer treatment had a 100 percent complication rate, defined as the need for further surgery. Local flaps, whether delayed or not, also had a high rate of complications. Myocutaneous flaps for ulcers had a 43 percent complication rate, with viable flaps lifting off radiated wound beds. Only myocutaneous flaps for breast reconstruction and omental flaps with skin grafts and Marlex mesh had no complications. The deeper tissue penetration of modern radiotherapy techniques may make skin grafts and flaps less useful. In reconstruction of radiation ulcers, omental flaps and myocutaneous flaps are especially useful, particularly if the radiation damage can be fully excised. The pull of gravity appears detrimental to myocutaneous flap healing and, if possible, should be avoided by flap design

  18. [Personalized medicine in radiotherapy: practitioners' perception].

    Science.gov (United States)

    Britel, Manon; Foray, Nicolas; Préau, Marie

    2015-01-01

    This exploratory study was designed to investigate the representations of radiotherapists in relation to personalized medicine. On the basis of current?>' available radiotherapy predictive tests, we tried to understand how these tests could be used in routine radiotherapy practice and in what way this possible change of practices could affect the role of radiotherapists in treatment protocols. In the absence of any available data allowing the construction of a quantitative tool, qualitative data were recorded by individual interviews with radiotherapists. Based on textual data analysis, a second national quantitative phase was conducted using a self-administered questionnaire. Crossover analysis of the two datasets highlighted the interest of radiotherapists in personalized medicine and the use of predictive tests, while indicating certain limitations and concerns in relation to ethical issues related to personalized medicine in oncology and the physician's position. PMID:26752033

  19. Staffing in Radiotherapy: An Activity Based Approach

    International Nuclear Information System (INIS)

    Radiotherapy requires competent professional staff to ensure safe and effective patient treatment and management. There is a need to provide guidelines that recommend appropriate staffing levels to support the initiation of new services as well as the expansion or upgrade of existing services as even simple upgrades or replacement of existing equipment may have a significant impact on staffing needs. Similarly, the introduction of education and training programmes will require staffing adjustments. A calculation algorithm was developed to predict staffing levels based on the inputs that are known or can be easily estimated. This publication complements other IAEA publications used to support the initiation of basic radiation medicine services including Setting up a Radiotherapy Programme: Clinical, Medical Physics, Radiation Protection and Safety Aspects, published in 2008

  20. Some new physical data for magnetic radiotherapy

    International Nuclear Information System (INIS)

    The magnetic radiotherapy consisting of three subsystems - the beam, the irradiation medium, and the electromagnetic field - offers some advantages as compared to the standard radiotherapy consisting of two subsystems - the beam and irradiation medium. These advantages refer to: the movement of the absorbed dose longitudinal distribution to the entrance surfaces, the increase of the absorbed dose gradient, the increase of the absorbed dose in the target volume, the decrease of the beam penetration depth and others. The electron path or the penetration depth into the absorbing medium is equivalent to the actual electron effective range in the standard electron therapy (without a magnetic field). This paper presents some new physical data referring to the penetration depth. These data are obtained for electron energies between 1 MeV and 50 MeV and magnetic induction ranging between 1 V s m-2 and 5 V s m-2. (Author)

  1. Dose calculation system for remotely supporting radiotherapy

    International Nuclear Information System (INIS)

    The dose calculation system IMAGINE is being developed keeping in mind remotely supporting external radiation therapy using photon beams. The system is expected to provide an accurate picture of the dose distribution in a patient body, using a Monte Carlo calculation that employs precise models of the patient body and irradiation head. The dose calculation will be performed utilising super-parallel computing at the dose calculation centre, which is equipped with the ITBL computer, and the calculated results will be transferred through a network. The system is intended to support the quality assurance of current, widely carried out radiotherapy and, further, to promote the prevalence of advanced radiotherapy. Prototypes of the modules constituting the system have already been constructed and used to obtain basic data that are necessary in order to decide on the concrete design of the system. The final system will be completed in 2007. (authors)

  2. Pelvic radiotherapy and sexual dysfunction in women

    DEFF Research Database (Denmark)

    Jensen, Pernille Tine; Froeding, Ligita Paskeviciute

    2015-01-01

    focus on late effects and an increasing awareness that patient reported outcomes (PROs) i.e., patient assessment of physical, social, psychological, and sexual functioning provides the most valid information on the effects of cancer treatment. Following cure of cancer allow survivors focus on quality of...... life (QOL) issues; sexual functioning has proved to be one of the most important aspects of concern in long-term survivors. METHODS: An updated literature search in PubMed was performed on pelvic radiotherapy and female sexual functioning/dysfunction. Studies on gynaecological, urological and...... gastrointestinal cancers were included. The focus was on the period from 2010 to 2014, on studies using PROs, on potential randomized controlled trials (RCTs) where female sexual dysfunction (FSD) at least constituted a secondary outcome, and on studies reporting from modern radiotherapy modalities. RESULTS: The...

  3. Radiotherapy of early glottic cancer. II

    International Nuclear Information System (INIS)

    A detailed retrospective analysis of the results and complications of treatment of early glottic cancers is presented. Two hundred and four patients treated by radiotherapy at the Antoni van Leeuwenhoek Ziekenhuis in Amsterdam are reviewed. The results are analyzed in terms of local control, cure and complication rates. These data are compared and contrasted with a similar group of patients treated at the Princess Margaret Hospital during the same time period. It is concluded that the risk of major complications in the larynx from radiotherapy rises very rapidly once the dose of 2050 ret is exceeded. The presence of diabetes and/or hypertension and the severity of acute reaction are related to the subsequent risk of major complications. The dose cure curve for early glottic cancer has been found to be flat over the dose range considered

  4. Complications of radiotherapy in oncologic patients

    International Nuclear Information System (INIS)

    Reasons, mechanisms of development and features of clinical course of radiation response (injuries) in different organs and systems in patients with lung, uterus neck, mammary and thyroid gland cancer are described. Their clinical classification is presented. Dependences of frequency, severity and time of occurrence of radiation reactions (injuries) on the absorbed radiation dose value, time-dose-fractioning factor, localization and size of the neoplasm and on other parameters are demonstrated. Results of complex examination of oncologic patients with radiation reactions and injuries are presented. Principles of prophylactic medical examination of patients subjected to radiotherapy are described. Recommendation on the optimization of radiotherapy methods and prophylaxis of its complications are given. 56 refs.; 22 figs.; 4 tabs

  5. Voice change after radiotherapy: some preliminary results

    International Nuclear Information System (INIS)

    A one-third octave spectral analysis was performed on two sentences spoken by 5 patients with laryngeal cancer, 5 with head/neck cancer not involving the vocal cords, and 12 normal subjects. Recordings were made prior to and at weekly intervals during radiotherapy as well as at periodic intervals post-treatment. Patients with laryngeal cancer exhibited lower spectral levels than normal throughout radiotherapy as well as several months post-treatment. By one year after treatment, the spectral levels of these patients were largely in the normal range. Patients with head/neck cancer not involving the vocal cords exhibited greater than normal sound pressure levels throughout most of the spectrum. These levels remained high even at one month post-treatment. Irradiation of normal vocal cord tissue also seems to result in higher spectral levels

  6. ARCON in experimental and clinical radiotherapy

    OpenAIRE

    Rojas Callejas, Ana Maria

    2004-01-01

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

  7. Radiotherapy in skin cancer - present day aspects

    International Nuclear Information System (INIS)

    Skin carcinomas (SC) are the leading ones in the structure of oncological morbidity in both genders in Bulgaria, as well as in white populations in the world. Regardless of their high frequency, their treatment is successful and mortality due to SC has been reduced by 20 - 30% during the last decades. In Bulgaria SC in 2003 comprise 9.3% of all oncological diseases in men and women. According to their frequency they occupy the second phase after lung cancer in men and breast cancer in women. The treatment of SC is realized applying various therapeutic approaches, distinguished as basic (radical) and alternative ones. The first include surgical treatment and radiotherapy (RT) (definitive or adjuvant) and the alternative ones - curettage and electro-coagulation, cryotherapy, local chemotherapy and immunotherapy, systemic chemotherapy, etc. When defining the therapeutic approach, the method affording the best chances of curing with acceptable cosmetic results should be selected. The present review is aimed at considering the contemporary aspects in RT of SC, including used radiotherapy methods and techniques, volumes, doses, fractionation, and achieved therapeutic effects. The indications for implementing definitive and adjuvant RT are given in detail. The applied radiotherapy methods - external beam RT and brachytherapy, are also discussed. The used planned radiotherapy volumes, doses, fractionation schemes, attained therapeutic effects and possible radiation reactions are considered as well. The curability of SC is high, exceeding 90% after adequate treatment. Regardless of the fact that RT has partially ceded its leading role in SC treatment, it still remains to be one of the basic and successful therapeutic approaches

  8. Subacute cutaneous lupus erythematosus triggered by radiotherapy

    OpenAIRE

    Kolm, I.; Pawlik, E; Eggmann, N.; Kamarachev, J; Kerl, K. (Kornelius); French, L E; Hofbauer, G.F.L.

    2013-01-01

    BACKGROUND: The origin of collagen autoimmune diseases is not fully understood. Some studies postulate a mechanism of molecular mimicry or heterologous immunity following viral infections triggering autoimmunity. Apart from infections, other exogenous factors such as visible light or X-rays have been reported to incite autoimmunity. CASE REPORT: We report a case of histologically and serologically confirmed subacute lupus erythematosus (SCLE) following radiotherapy for breast cancer. DI...

  9. Role of palliative radiotherapy in brain metastases

    Directory of Open Access Journals (Sweden)

    Ramesh S Bilimagga

    2009-01-01

    Full Text Available Background: Brain metastases are a common manifestation of systemic cancer and exceed primary brain tumors in number and are a significant cause of neurologic problems. They affect 20-40% of all cancer patients. Aggressive management of brain metastases is effective in both symptom palliation and prolonging the life. Radiotherapy has a major role to play in the management of brain metastases. AIM: The aim of the study was to know the outcome of palliative radiotherapy in symptomatic brain metastases in terms of improvement in their performance status. Materials and Methods: This is a retrospective study of 63 patients diagnosed to have brain metastases and treated with palliative whole brain radiotherapy to a dose of 30 Gy in 10 fractions over two weeks between June 1998 and June 2007. Diagnosis was done in most of the cases with computed tomography scan and in a few with magnetic resonance imaging. Improvement in presenting symptoms has been assessed in terms of improvement in their performance status by using the ECOG scale. Results: Fifty-four patients completed the planned treatment. Eight patients received concurrent Temozolamide; 88% of patients had symptom relief at one month follow-up; 39/54 patients had a follow-up of just one to three months. Hence survival could not be assessed in this study. Conclusion: External beam radiotherapy in the dose of 30 Gy over two weeks achieved good palliation in terms improvement in their performance status in 88% of patients. Addition of concurrent and adjuvant Timozolamide may improve the results.

  10. Polarography of Walker tumor submitted to radiotherapy

    International Nuclear Information System (INIS)

    A polarographic study of oxigen was done in 57 rats inoculated with walker 256 tumor and Platinum electrode implanted in muscle and in tumor. The goal of the research was the study of oxygen in tumor before and after irradiation. Tumor growth caused a decrease in tumoral oxygen. Oxigen was always lower in the tumor than in the muscle. Radiotherapy with 2000 rad (but not with 1000 rad) increased oxygen in the tumor

  11. Theoretical exploration on ultra-fractionated radiotherapy

    International Nuclear Information System (INIS)

    This study based on the hyper-radiosensitivity (HRS) effect, a new tumour radiotherapy method - ultra-fractionation has been devised. Compared with conventional fractionation, the dose per fraction is decreased from 2Gy to 0.2 ∼ 0.5Gy for the ultra-fractionation. Although the amount of fractions is increased in order to reach the same therapeutic efficacy, the total dose is significantly reduced

  12. Radiotherapy for treatment of induratio penis plastica

    International Nuclear Information System (INIS)

    Radiotherapy is shown to be an effective, low-cost and non-invasive modality for treatment of induratio penis plastica. Its efficiency could be proven especially for inflammatory stages of the disease, or as an alternative after failure of conventional treatment. A total dose of no more than 20-25 Gy was found to achieve clear improvements in two thirds of the patients treated, while avoiding at the same time cosmetically disadvantageous late effects. (orig./CB)

  13. Hypofractionated whole breast radiotherapy: current perspectives

    OpenAIRE

    Koulis TA; Phan T; Olivotto IA

    2015-01-01

    Theodora A Koulis, Tien Phan, Ivo A Olivotto Department of Oncology, University of Calgary, Tom Baker Cancer Centre, Calgary, AB, Canada Abstract: Adjuvant radiotherapy (RT) is an important part of breast cancer management but the dose and fractionation schedules used are variable. A total of 50 Gy in 25 daily fractions delivered over 5 weeks is often considered the "standard" adjuvant RT prescription. Hypofractionated regimes such as 42.5 Gy in 16 daily fractions or 40 Gy ...

  14. Towards online MRI-guided radiotherapy

    OpenAIRE

    Bol, G.H.

    2015-01-01

    First, we present two offline position verification methods which can be used in radiotherapy for detecting the position of the bony anatomy of a patient automatically with portal imaging, even if every single portal image of each segment of an (IMRT) treatment beam contains insufficient matching information. Additional position verification fields will no longer be necessary, which speeds up the treatment and reduces the total dose to the patient. Second, a tool is described which enhances t...

  15. Hypothyroidism After Radiotherapy for Nasopharyngeal Cancer Patients

    International Nuclear Information System (INIS)

    Purpose: The aim of this study was to determine the long-term incidence and possible predictive factors for posttreatment hypothyroidism in nasopharyngeal carcinoma (NPC) patients after radiotherapy. Methods and Materials: Four hundred and eight sequential NPC patients who had received regular annual thyroid hormone surveys prospectively after radiotherapy were included in this study. Median patient age was 47.3 years, and 286 patients were male. Thyroid function was prospectively evaluated by measuring thyroid-stimulating hormone (TSH) and serum free thyroxine (FT4) levels. Low FT4 levels indicated clinical hypothyroidism in this study. Results: With a median follow-up of 4.3 years (range, 0.54-19.7 years), the incidence of low FT4 level was 5.3%, 9.0%, and 19.1% at 3, 5, and 10 years after radiotherapy, respectively. Hypothyroidism was more common with early T stage (p = 0.044), female sex (p = 0.037), and three-dimensional conformal therapy with the altered fractionation technique (p = 0.005) after univariate analysis. N stage, chemotherapy, reirradiation, and neck electron boost did not affect the incidence of hypothyroidism. Younger age and conformal therapy were significant factors that determined clinical hypothyroidism after multivariate analysis. Overall, patients presented with a low FT4 level about 1 year after presenting with an elevated TSH level. Conclusion: Among our study group of NPC patients, 19.1% experienced clinical hypothyroidism by 10 years after treatment. Younger age and conformal therapy increased the risk of hypothyroidism. We suggest routine evaluation of thyroid function in NPC patients after radiotherapy. The impact of pituitary injury should be also considered.

  16. Radiotherapy in non-Hodgkin lymphomas

    International Nuclear Information System (INIS)

    The treatment of non-Hodgkin lymphomas (NHL) is discussed. The use of radiotherapy, chemotherapy or both in a combined therapy is studied considering several aspects as age of the patients (adults vs children), size and extension of the lymphoma, stage of the disease. It is mentioned that more advanced cases and those with more aggressive histology need combined modality treatments or even just chemotherapy. (M.A.C.)

  17. Radiotherapy in veterinary medicine: beginnings and perspectives

    International Nuclear Information System (INIS)

    This work presents a brief historical about the use of ionizing radiations in Veterinary Medicine, instructing the physical beginnings and techniques wrapped in the realization of the proceedings of radiotherapy in animals, illustrating some treated cases, highlighting the difficulties and pointing to the perspectives and importance of the acting of the medical physics in this kind of therapeutic still little used in the national scenery. (author)

  18. Radiotherapy treatment planning linear-quadratic radiobiology

    CERN Document Server

    Chapman, J Donald

    2015-01-01

    Understand Quantitative Radiobiology from a Radiation Biophysics PerspectiveIn the field of radiobiology, the linear-quadratic (LQ) equation has become the standard for defining radiation-induced cell killing. Radiotherapy Treatment Planning: Linear-Quadratic Radiobiology describes tumor cell inactivation from a radiation physics perspective and offers appropriate LQ parameters for modeling tumor and normal tissue responses.Explore the Latest Cell Killing Numbers for Defining Iso-Effective Cancer TreatmentsThe book compil

  19. Targeting Radiotherapy to Cancer by Gene Transfer

    OpenAIRE

    R. J. Mairs; Boyd, M.

    2003-01-01

    Targeted radionuclide therapy is an alternative method of radiation treatment which uses a tumor-seeking agent carrying a radioactive atom to deposits of tumor, wherever in the body they may be located. Recent experimental data signifies promise for the amalgamation of gene transfer with radionuclide targeting. This review encompasses aspects of the integration of gene manipulation and targeted radiotherapy, highlighting the possibilities of gene transfer to assist the targeting of cancer ...

  20. MRI-guided radiotherapy for renal tumours

    OpenAIRE

    Stam, M.K.

    2013-01-01

    The current surgical treatment for renal cell carcinoma (RCC) experiences complications due to the invasiveness of the treatment. Minimally invasive alternative treatments, such as radiofrequency and cryogen ablation, have fewer complications but a lower local control. Radiotherapy is an established minimally- to non-invasive treatment and might improve morbidity or outcome for RCC patients. A precise radiation technique will be necessary since the kidney moves during respiration and is very ...

  1. Lymphocyte subpopulations in mammary cancer after radiotherapy

    International Nuclear Information System (INIS)

    B- and T-lymphocytes, identified by two methods of rosette-formation with sheep erythrocytes, fall to low levels within 1 week of the start of post-operative radiotherapy for cancer of the breast. Fifty-two such patients are compared with 34 age- and disease-matched patients treated by mastectomy alone. The B-lymphopenia reverts to normal levels by 10 months while the T-lymphopenia persists for at least 2 to 4 years

  2. Direct costs of radiotherapy for rectal cancer: a microcosting study

    OpenAIRE

    Hanly, Paul; Céilleachair, Alan Ó; Skally, Máiréad; O’Neill, Ciaran; Sharp, Linda

    2015-01-01

    Background Radiotherapy provides significant benefits in terms of reducing risk of local recurrence and death from rectal cancer. Despite this, up-to-date cost estimates for radiotherapy are lacking, potentially inhibiting policy and decision-making. Our objective was to generate an up-to-date estimate of the cost of traditional radiotherapy for rectal cancer and model the impact of a range of potential efficiency improvements. Methods Microcosting methods were used to estimate total direct r...

  3. Role of Radiotherapy in Modern Treatment of Hodgkin's Lymphoma

    OpenAIRE

    Kheng-Wei Yeoh; N. George Mikhaeel

    2011-01-01

    Hodgkin's Lymphoma was incurable until the advent of effective therapeutic radiation around the first half of the 20th century. As survival rates improved, the long-term toxicities from radiotherapy began to emerge. This together with the availability of effective chemotherapy has encouraged a combined modality approach for early-staged disease and the omission of radiotherapy in advanced-staged disease. The differing toxicities of radiotherapy and chemotherapy has promoted ongoing research t...

  4. The role of image guidance in respiratory gated radiotherapy

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia; Juhler-Nøttrup, Trine; Fredberg Persson, Gitte;

    2008-01-01

    Respiratory gating for radiotherapy beam delivery is a widely available technique, manufactured and sold by most of the major radiotherapy machine vendors. Respiratory gated beam delivery is intended to limit the irradiation of tumours moving with respiration to selected parts of the respiratory ...... therefore of utmost importance for the safe introduction of respiratory gating. In this short overview, suitable image guidance strategies for respiratory gated radiotherapy are reviewed for two cancer sites; breast cancer and lung tumours....

  5. Rehabilitation of patients with laryngeal and lung cancer after radiotherapy

    International Nuclear Information System (INIS)

    The ways of medical and social-occupational rehabilitation after a course of radiotherapy in patients with respiratory system cancer have been determined. Medical rehabilitation in patients with lung cancer comprises expedient planning of radiotherapy by means of systematic medicamental treatment. It is shown that it is necessary to place the patients in special rehabilitation departments after radiotherapy of carry out the treatment of pneumonities

  6. Sacral plexus injury after radiotherapy for carcinoma of cervix

    International Nuclear Information System (INIS)

    A 42-year-old woman developed lower extremity weakness and sensory loss 1 year after external and intracavitary radiotherapy for Stage IB carcinoma of cervix. She has been followed for 5 years posttreatment, and the neurologic abnormalities have persisted, but no evidence of recurrent carcinoma has been found. We believe this to be a rare case of sacral plexus radiculopathy developing as a late complication after radiotherapy. Suggestions are made for improving the radiotherapy technique to prevent this complication in future cases

  7. Nuclides for radiotherapy: an overview

    International Nuclear Information System (INIS)

    With the emergence of new, biological vehicles of great organ specificity (e.g. steroid hormones, antibodies) the concept of systemic tumor therapy with the aid of radiotherapeutica has gained new momentum. In order to assess the options open for optimal adaptation of the radiation properties to the pharmacocinetics of a vehicle, a search was done to identify potentially useful therapeutic radionuclides. Main criteria for selection were half life, low gamma-yield and stable daughter nuclide. The resulting possibilities fall into 4 categories: 1) alpha-emitters (At-211); 2) beta/sup -/-emitters that can be prepared in a carrierfree fashion (P-32, S-35, As-77, Y-90, Ag-111, Pm-149, Tb-161, Lu-177), 3) beta/sup -/-emitters with carrier added (Pd-109, Pr-142, Gd-159, Er-169, Tm-172, Yb-175, Re-188, Ir-194, Pt-197) and 4) electron capture nuclides, emitting Auger-cascades (Cr-51, Ga-67, Ge-71, Br-77, Ru-97, Sb-119, I-123, Cs-129, Nd-140, Er-165, Ta-177, Hg-197, Tl-201). Among the 4th group some well known, diagnostically used nuclides are found. Their therapeutic use necessitates the precise localisation in or very near the genetic material of the cell to be killed; only there the destructive power of the very short range Auger-electrons can be used. For each of the selected nuclides a summary of decay data, possibilities of preparation and chemical reactivity for labelling of vehicles is given. (author)

  8. Clinico-statistical study on radiotherapy prostheses

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Takaaki; Taniguchi, Hisashi; Sunahara, Yuichi; Shinozuka, Osamu; Suzuki, Ruri; Ohyama, Takashi; Takeda, Masamune [Tokyo Medical and Dental Univ. (Japan). School of Dentistry

    1996-06-01

    Various radiotherapy prostheses, including spacer, protector, carrier and mold, are frequently used for oral and maxillofacial cancer patients because they enhance the treatment efficacy of radiotherapy and protect adjacent normal tissue from irradiation. Therefore a clinical investigation was carried out on 310 cases of radiotherapy prostheses applied in our clinic from 1981 to 1995. The results were as follows: Sex ratio (male: female) of patients was 1.67: 1 and the number of the patients at the age of 60-69 was the largest. Spacer accounted for 81.0% of prostheses, followed by mold (10.6%), protector (5.5%) and carrier (2.9%). As for the site of malignant tumor, the tongue was 77.1% of all cases. External irradiation was already performed on 23.3% of all cases. Abutment teeth remained in 85.9% of 304 cases in which the prostheses were applied intraorally. The average time to make the prostheses was 12.4 days. As for the retention of the prosthesis to the mouth, a ball clasp was used most frequently in spacer and carrier, and overlay type was applied most frequently in mold and protector. As for the retention of shield to carrier in mold cases, mechanical interlocking of the resin parts of carrier and shield was 75.8% of the cases. (author)

  9. Quality assurance network in radiotherapy in Denmark

    International Nuclear Information System (INIS)

    Quality Assurance in radiotherapy has in the past mainly been concerned with control of the physical dosimetry since this, as demonstrated recently may affect the outcome of the treatment for a large number of patients. In Denmark control of physical dose in radiotherapy centres have been carried out in 1972 and in 1980 as part of a comparison between centres in Scandinavia. These comparisons have played a major role in removing important dosimetry differences. In a recent dosimetry comparison carried out in 1992 no deviation between stated and measured dose above 3% have been discovered. The majority of radiotherapy with curative intent is carried out according to national protocols. DBCG (breast) and DAHANCA (head and neck) are two well known examples. Following the encouraging results quality control groups for the physical dosimetry have been created. A head and neck phantom in solid water has been designed for dosimetry control of the physical dose, i.e. check of the dose-planning system and fabrication of compensators. The phantom contains low and high density volumes simulating air and bone. A ionisation chamber can be placed in six different positions in the phantom. The phantom is used both as a check of dose planning and as a control of appropriate drawing of treatment portals in various clinical situations. (author)

  10. Multimedia educational services in stereotactic radiotherapy.

    Science.gov (United States)

    Bazioglou, M; Theodorou, K; Kappas, C

    1999-01-01

    The computer-based learning methods in medicine have been well established as stand-alone learning systems. Recently, these systems were enriched with the use of telematics technology to provide distance learning capabilities. Stereotactic radiotherapy is one of the most representative advanced radiotherapy techniques. Due to the multidisciplinary character of the technique and the rapid evolution of technology implemented, the demands in training have increased. The potential of interactive multimedia and Internet technologies for the achievement of distance learning capabilities in this domain are investigated. The realization of a computer-based educational program in stereotactic radiotherapy in a multimedia format is a new application in the computer-aided distance learning field. The system is built according to a client and server architecture, based on the Internet infrastructure, and composed of server nodes. The impact of the system may be described in terms of: time and transportation costs saving, flexibility in training (scheduling, rate and subject selection), online communication and interaction with experts, cost effective access to material (delivery or access by a large number of users and revision of the material by avoiding high costs of computer-based training systems and database development). PMID:10394345

  11. Guideline of stereotactic radiotherapy of body trunk

    International Nuclear Information System (INIS)

    The guideline is issued for safe and effective practice of the stereotactic radiotherapy of body trunk by giving appropriate methodologies and their theoretical backgrounds to radiological stuff concerned, such as doctors, technologists, physicists, quality assurance (QA)/quality control (QC) personnel, and nurses. The issue is motivated by the recent and expected increase of facilities conducting the therapy popularized from its approval by health insurance authorities in 2004, is based on the drafts by the Study Group for improving prognosis of the accurate 3-D radiotherapy organized in the MHLW and by Jap. 3-D Conformal External Beam Radiotherapy Group and, after edition by QA committee of Jap. Soc. Ther. Radiol. Oncol., is herein published by the Society. The guideline is composed mainly from 4 chapters of Introduction, Clinical practice, Physics and technology, and QA/QC of equipments and systems. The second chapter contains, concerning the therapy, its definition, contraindication, application to health insurance (applicable diseases and requirement), target setting, radiation dose and fractionation, risk organs (serial and parallel ones) and dose limits, and progress observation post therapy. The third chapter, its definition and methods, therapeutic planning, and actual performance, and the forth, the principle, essential concept, items particularly needed (dosimetry and mechanical/geometrical accuracy of equipments, equipments for therapy planning, and QA/QC of the system). The guideline is to be revised within 2-3 years hereafter. (R.T.)

  12. Concomitant boost radiotherapy in oropharynx carcinomas

    International Nuclear Information System (INIS)

    Fifty-five patients with resectable and unresectable oropharynx carcinomas were treated with concomitant boost radiotherapy. Forty-two of the patients (76%) had stages III-IV disease. Although none of the patients had undergone major surgery to the primary tumor, 11 had neck dissections prior to radiotherapy, and 19 (35%) received chemotherapy. The planned total tumor dose was 69.9 Gy, delivered over 5.5 weeks. During the last 3.5 weeks, a boost to the initial gross disease was delivered in 13 fractions of 1.5 Gy each, as a second daily fraction in a progressively accelerated schedule; the prescribed dose outside the boost volume thus was 50.4 Gy. Median follow-up for surviving patients was 31.5 months (range: 16-65 months). All patients but one completed the planned radiotherapy schedule. According to the RTOG scoring system, 48 patients (88%) presented with grades 3-4 acute toxicity. The rate of grades 3-4 late complications was 12%. At three years the actuarial locoregional control rate was 69.5% and overall survival was 60%. We conclude that this concomitant boost schedule is feasible and does not seem to be associated with an excess risk of late complications. Acute toxicity was higher in association with chemotherapy, but remained manageable. Although the oncological results appear encouraging, evaluation of the efficacy of concomitant boost schedules compared with conventionally fractionated irradiation with or without concomitant chemotherapy requires prospective randomized trials. (orig.)

  13. Concomitant boost radiotherapy in oropharynx carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Bieri, S.; Allal, A.S.; Kurtz, J.M. [Ospedale San Giovanni, Bellinzona (Switzerland). Dept. of Radiation Oncology; Dulguerov, P.; Lehmann, W. [Geneva Univ. Hospital (Switzerland). Div. of Head and Neck Surgery

    1998-12-31

    Fifty-five patients with resectable and unresectable oropharynx carcinomas were treated with concomitant boost radiotherapy. Forty-two of the patients (76%) had stages III-IV disease. Although none of the patients had undergone major surgery to the primary tumor, 11 had neck dissections prior to radiotherapy, and 19 (35%) received chemotherapy. The planned total tumor dose was 69.9 Gy, delivered over 5.5 weeks. During the last 3.5 weeks, a boost to the initial gross disease was delivered in 13 fractions of 1.5 Gy each, as a second daily fraction in a progressively accelerated schedule; the prescribed dose outside the boost volume thus was 50.4 Gy. Median follow-up for surviving patients was 31.5 months (range: 16-65 months). All patients but one completed the planned radiotherapy schedule. According to the RTOG scoring system, 48 patients (88%) presented with grades 3-4 acute toxicity. The rate of grades 3-4 late complications was 12%. At three years the actuarial locoregional control rate was 69.5% and overall survival was 60%. We conclude that this concomitant boost schedule is feasible and does not seem to be associated with an excess risk of late complications. Acute toxicity was higher in association with chemotherapy, but remained manageable. Although the oncological results appear encouraging, evaluation of the efficacy of concomitant boost schedules compared with conventionally fractionated irradiation with or without concomitant chemotherapy requires prospective randomized trials. (orig.)

  14. Radiotherapy in the treatment of ameloblastoma

    International Nuclear Information System (INIS)

    There is a lack of well-documented evidence in the literature concerning the relative radioresponsiveness or radioresistance of ameloblastomas, although they are generally considered radioresistant. Most of the previous papers referring to this subject lack acceptable histopathologic proof of the diagnosis, adequate radiotherapeutic data, and/or follow-up information; many predate the use of megavoltage irradiation. The present article reports 5 cases of ameloblastoma that were treated by radiotherapy, 3 by megavoltage irradiation. All have been confirmed histologically by an oral pathologist, all have adequate radiotherapeutic data and, with one exception, adequate follow-up information. In addition, the reasons for our present lack of knowledge of this subject are discussed; objective criteria are presented for evaluating the results of radiotherapy on ameloblastomas; the only other series of ameloblastomas treated by megavoltage irradiation is analyzed. Although radiotherapy can reduce the size of an ameloblastoma, primarily that part of the tumor which has expanded the jaw or broken into the soft tissues, it does not appear to be an appropriate treatment for an operable ameloblastoma. Its main use is in inoperable cases, primarily in the posterior maxilla. (author)

  15. Complications after radiotherapy in the ENT area

    Directory of Open Access Journals (Sweden)

    Chiesa-Estomba, CM, Araujo-daCosta, AS, Rivera-Schmitz, T

    2013-10-01

    Full Text Available Introduction: Radiotherapy is part of the treatment of oncological pathology of head and neck, being useful as therapeutic and supplementary strategy. It is possible associate to chemotherapeutic or radiosensitizing to enhance their effectiveness as well as radiation protection measures used to prevent overexposure of tissues. However, despite all this there are multiple potential complications secondary to the use of radiotherapy.Materials and Methods: Here we present a series of complications that occurred in the late phase of radiation therapy in 4 patients.Results: A total of 4 patients of which 3 presented the diagnosis of nasopharyngeal carcinoma and one vocal cord carcinoma, which presented complications: critical stenosis of left carotid artery in the cervical cutaneous fistula more radionecrosis of vertebrae C5 and C6, radionecrosis of pre-vertebral muscles and C1 and C2 vertebrae and left carotid artery pseudoaneurysm.Conclusions: In our series the hyperbaric chamber favored the improvement in terms of tissue necrosis, in terms of critical stenosis the patient required anticoagulation, while the pseudoaneurysm required embolization by interventional radiology. So unquestionably the therapeutic effect of radiotherapy in the field of head and neck oncology, but complications because of this should be taken into account when assessing the patient successively.

  16. Results of the national audits radiotherapy program

    International Nuclear Information System (INIS)

    The National Audit Programme in Radiotherapy in Cuba works regularly 8 years visiting each country's radiotherapy service at least once every two years, during the visit involving two physicists and an oncologist radiation therapist. This paper presents the main features of the program and its main . Early detection deficiencies in the work of the Radiation Therapy Services to may cause radiological risk situations for both patients and workers and the general public. Help with their comments to the continuous improvement of quality treatments. During audit visits is reviewed throughout the process of radiation from that the patient comes to the monitoring service. This is done by dividing the audits into three groups or aspects Clinical Aspects, Aspects of Safety and Quality Control Aspects of the equipment. Methodological guidelines have been established for conducting audits and they serve as standards of quality in radiation therapy, these guidelines also allow quantification of the . It has identified the main gaps in services that affect quality treatments. After each visit, leave recommendations may be directed to service itself, to the direction of the provincial hospital or health. We believe that the National Audit Programme in Radiotherapy is a efficient tool in controlling the quality of treatments given and at the same time with its recommendations to help improve services of continuous quality. (author)

  17. Contemporary Breast Radiotherapy and Cardiac Toxicity.

    Science.gov (United States)

    Yeboa, Debra Nana; Evans, Suzanne Buckley

    2016-01-01

    Long-term cardiac effects are an important component of survivorship after breast radiotherapy. The pathophysiology of cardiotoxicity, history of breast radiotherapy, current methods of cardiac avoidance, modern outcomes, context of historical outcomes, quantifying cardiac effects, and future directions are reviewed in this article. Radiation-induced oxidative stress induces proinflammatory cytokines and is a process that potentiates late effects of fibrosis and intimal proliferation in endothelial vasculature. Breast radiation therapy has changed substantially in recent decades. Several modern technologies exist to improve cardiac avoidance such as deep inspiration breath hold, gating, accelerated partial breast irradiation, and use of modern 3-dimensional planning. Modern outcomes may vary notably from historical long-term cardiac outcomes given the differences in cardiac dose with modern techniques. Methods of quantifying radiation-related cardiotoxicity that correlate with future cardiac risks are needed with current data exploring techniques such as measuring computed tomography coronary artery calcium score, single-photon emission computed tomography imaging, and biomarkers. Placing historical data, dosimetric correlations, and relative cardiac risk in context are key when weighing the benefits of radiotherapy in breast cancer control and survival. Estimating present day cardiac risk in the modern treatment era includes challenges in length of follow-up and the use of confounding cardiotoxic agents such as evolving systemic chemotherapy and targeted therapies. Future directions in both multidisciplinary management and advancing technology in radiation oncology may provide further improvements in patient risk reduction and breast cancer survivorship. PMID:26617212

  18. Clinico-statistical study on radiotherapy prostheses

    International Nuclear Information System (INIS)

    Various radiotherapy prostheses, including spacer, protector, carrier and mold, are frequently used for oral and maxillofacial cancer patients because they enhance the treatment efficacy of radiotherapy and protect adjacent normal tissue from irradiation. Therefore a clinical investigation was carried out on 310 cases of radiotherapy prostheses applied in our clinic from 1981 to 1995. The results were as follows: Sex ratio (male: female) of patients was 1.67: 1 and the number of the patients at the age of 60-69 was the largest. Spacer accounted for 81.0% of prostheses, followed by mold (10.6%), protector (5.5%) and carrier (2.9%). As for the site of malignant tumor, the tongue was 77.1% of all cases. External irradiation was already performed on 23.3% of all cases. Abutment teeth remained in 85.9% of 304 cases in which the prostheses were applied intraorally. The average time to make the prostheses was 12.4 days. As for the retention of the prosthesis to the mouth, a ball clasp was used most frequently in spacer and carrier, and overlay type was applied most frequently in mold and protector. As for the retention of shield to carrier in mold cases, mechanical interlocking of the resin parts of carrier and shield was 75.8% of the cases. (author)

  19. Accidental exposures in radiotherapy: an history

    International Nuclear Information System (INIS)

    Radiotherapy accidents are exceedingly rare. However, they may have major negative consequences: for health (and sometimes life) of victims as well as for the trust that patients put in radiotherapy and radiation oncolysis. Each accident must be pointed out, analysed and reported, in order to allow preventive actions, avoiding repetitive accidents. Through examples of majors accidents occurred all over the world in the last decades, affecting professionals, public or patients themselves, the necessity of transparency is demonstrated. The International Commission of Radiobiological Protection has drawn positive lessons from such accidents and insists on following recommendations: necessity of sufficient number and competent professionals, importance of continuous and initial education, information of professionals and, in general, a strict Quality Assurance program. It is clear that each radiotherapy center remains at risk for errors. It is essential to develop preventive procedures to avoid transformation of errors into accidents. In that context, complete and detailed description and reports of each anomaly or incident must be encouraged as it is done for sectors of aviation or nuclear industry. Radiation oncology must develop such a culture of transparency and of systematic report of all incident. (authors)

  20. Development of a multichannel dosimeter for radiotherapy

    International Nuclear Information System (INIS)

    In radiotherapy, verification of the patient dose is of great important for the success of the treatment. Uncertainties in the evaluation of this dose can produce serious complications such as the loss of the control of the disease and damage to normal tissue. Semiconductor detectors present advantages over other types of radiation detectors such as ionization chambers and thermoluminescent dosimeters including small dimensions, high sensitivity and fast response. In this work, a multichannel dosimetric system is linear with dose, for a 6 MV x-ray beam and also with a beam of cobalt-60 gamma rays. The coefficients of determination of the calibration curves were better then 0,9998 in all cases. The four sensors presented similar response with the dose for different field sizes. The variation of the response was smaller than 1%. In a related study, depth dose was measured, and the results showed a good agreement compared to theoretical values. The angular response of the detectors showed a variation of 7% for angles of 45 deg C. Using the Anderson Random phantom, dose at the isocenter was determined from measurements of the surface dose. From the results obtained it can be concluded that the dosimetric system developed is adequate for the evaluation of many parameters in radiation fields used in radiotherapy. This system can be used to measure the patient entrance dose under treatment conditions, and the equipment can be used in the radiotherapy quality assurance program. (author)