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Sample records for radiotherapy dose-volume effects

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

    International Nuclear Information System (INIS)

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

    2002-01-01

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

  2. Gastrointestinal toxicity of vorinostat: reanalysis of phase 1 study results with emphasis on dose-volume effects of pelvic radiotherapy

    International Nuclear Information System (INIS)

    Bratland, Åse; Dueland, Svein; Hollywood, Donal; Flatmark, Kjersti; Ree, Anne H

    2011-01-01

    In early-phase studies with targeted therapeutics and radiotherapy, it may be difficult to decide whether an adverse event should be considered a dose-limiting toxicity (DLT) of the investigational systemic agent, as acute normal tissue toxicity is frequently encountered with radiation alone. We have reanalyzed the toxicity data from a recently conducted phase 1 study on vorinostat, a histone deacetylase inhibitor, in combination with pelvic palliative radiotherapy, with emphasis on the dose distribution within the irradiated bowel volume to the development of DLT. Of 14 eligible patients, three individuals experienced Common Terminology Criteria of Adverse Events grade 3 gastrointestinal and related toxicities, representing a toxicity profile vorinostat has in common with radiotherapy to pelvic target volumes. For each study patient, the relative volumes of small bowel receiving radiation doses between 6 Gy and 30 Gy at 6-Gy intervals (V6-V30) were determined from the treatment-planning computed tomography scans. The single patient that experienced a DLT at the second highest dose level of vorinostat, which was determined as the maximum-tolerated dose, had V6-V30 dose-volume estimates that were considerably higher than any other study patient. This patient may have experienced an adverse radiation dose-volume effect rather than a toxic effect of the investigational drug. When reporting early-phase trial results on the tolerability of a systemic targeted therapeutic used as potential radiosensitizing agent, radiation dose-volume effects should be quantified to enable full interpretation of the study toxicity profile.

  3. Dose-Volume Constraints to Reduce Rectal Side Effects From Prostate Radiotherapy: Evidence From MRC RT01 Trial ISRCTN 47772397

    International Nuclear Information System (INIS)

    Gulliford, Sarah L.; Foo, Kerwyn; Morgan, Rachel C.; Aird, Edwin G.; Bidmead, A. Margaret; Critchley, Helen; Evans, Philip M. D.Phil.; Gianolini, Stefano; Mayles, W. Philip; Moore, A. Rollo; Sanchez-Nieto, Beatriz; Partridge, Mike; Sydes, Matthew R. C.Stat; Webb, Steve; Dearnaley, David P.

    2010-01-01

    Purpose: Radical radiotherapy for prostate cancer is effective but dose limited because of the proximity of normal tissues. Comprehensive dose-volume analysis of the incidence of clinically relevant late rectal toxicities could indicate how the dose to the rectum should be constrained. Previous emphasis has been on constraining the mid-to-high dose range (≥50 Gy). Evidence is emerging that lower doses could also be important. Methods and Materials: Data from a large multicenter randomized trial were used to investigate the correlation between seven clinically relevant rectal toxicity endpoints (including patient- and clinician-reported outcomes) and an absolute 5% increase in the volume of rectum receiving the specified doses. The results were quantified using odds ratios. Rectal dose-volume constraints were applied retrospectively to investigate the association of constraints with the incidence of late rectal toxicity. Results: A statistically significant dose-volume response was observed for six of the seven endpoints for at least one of the dose levels tested in the range of 30-70 Gy. Statistically significant reductions in the incidence of these late rectal toxicities were observed for the group of patients whose treatment plans met specific proposed dose-volume constraints. The incidence of moderate/severe toxicity (any endpoint) decreased incrementally for patients whose treatment plans met increasing numbers of dose-volume constraints from the set of V30≤80%, V40≤65%, V50≤55%, V60≤40%, V65≤30%, V70≤15%, and V75≤3%. Conclusion: Considering the entire dose distribution to the rectum by applying dose-volume constraints such as those tested here in the present will reduce the incidence of late rectal toxicity.

  4. Gastrointestinal toxicity of vorinostat: reanalysis of phase 1 study results with emphasis on dose-volume effects of pelvic radiotherapy

    LENUS (Irish Health Repository)

    Bratland, Ase

    2011-04-08

    Abstract Background In early-phase studies with targeted therapeutics and radiotherapy, it may be difficult to decide whether an adverse event should be considered a dose-limiting toxicity (DLT) of the investigational systemic agent, as acute normal tissue toxicity is frequently encountered with radiation alone. We have reanalyzed the toxicity data from a recently conducted phase 1 study on vorinostat, a histone deacetylase inhibitor, in combination with pelvic palliative radiotherapy, with emphasis on the dose distribution within the irradiated bowel volume to the development of DLT. Findings Of 14 eligible patients, three individuals experienced Common Terminology Criteria of Adverse Events grade 3 gastrointestinal and related toxicities, representing a toxicity profile vorinostat has in common with radiotherapy to pelvic target volumes. For each study patient, the relative volumes of small bowel receiving radiation doses between 6 Gy and 30 Gy at 6-Gy intervals (V6-V30) were determined from the treatment-planning computed tomography scans. The single patient that experienced a DLT at the second highest dose level of vorinostat, which was determined as the maximum-tolerated dose, had V6-V30 dose-volume estimates that were considerably higher than any other study patient. This patient may have experienced an adverse radiation dose-volume effect rather than a toxic effect of the investigational drug. Conclusions When reporting early-phase trial results on the tolerability of a systemic targeted therapeutic used as potential radiosensitizing agent, radiation dose-volume effects should be quantified to enable full interpretation of the study toxicity profile. Trial registration ClinicalTrials.gov: NCT00455351

  5. Dose-volume effects for pelvic bone marrow in predicting hematological toxicity in prostate cancer radiotherapy with pelvic node irradiation.

    Science.gov (United States)

    Sini, Carla; Fiorino, Claudio; Perna, Lucia; Noris Chiorda, Barbara; Deantoni, Chiara Lucrezia; Bianchi, Marco; Sacco, Vincenzo; Briganti, Alberto; Montorsi, Francesco; Calandrino, Riccardo; Di Muzio, Nadia; Cozzarini, Cesare

    2016-01-01

    To prospectively identify clinical/dosimetric predictors of acute/late hematologic toxicity (HT) in chemo-naÏve patients treated with whole-pelvis radiotherapy (WPRT) for prostate cancer. Data of 121 patients treated with adjuvant/salvage WPRT were analyzed (static-field IMRT n=19; VMAT/Rapidarc n=57; Tomotherapy n=45). Pelvic bone marrow (BM) was delineated as ilium (IL), lumbosacral, lower and whole pelvis (WP), and the relative DVHs were calculated. HT was graded both according to CTCAE v4.03 and as variation in percentage relative to baseline. Logistic regression was used to analyze association between HT and clinical/DVHs factors. Significant differences (p<0.005) in the DVH of BM volumes between different techniques were found: Tomotherapy was associated with larger volumes receiving low doses (3-20 Gy) and smaller receiving 40-50 Gy. Lower baseline absolute values of WBC, neutrophils and lymphocytes (ALC) predicted acute/late HT (p ⩽ 0.001). Higher BM V40 was associated with higher risk of acute Grade3 (OR=1.018) or late Grade2 lymphopenia (OR=1.005). Two models predicting lymphopenia were developed, both including baseline ALC, and BM WP-V40 (AUC=0.73) and IL-V40+smoking (AUC=0.904) for acute/late respectively. Specific regions of pelvic BM predicting acute/late lymphopenia, a risk factor for viral infections, were identified. The 2-variable models including specific constraints to BM may help reduce HT. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Biological-effective versus conventional dose volume histograms correlated with late genitourinary and gastrointestinal toxicity after external beam radiotherapy for prostate cancer: a matched pair analysis

    Directory of Open Access Journals (Sweden)

    Roeske John C

    2003-05-01

    Full Text Available Abstract Background To determine whether the dose-volume histograms (DVH's for the rectum and bladder constructed using biological-effective dose (BED-DVH's better correlate with late gastrointestinal (GI and genitourinary (GU toxicity after treatment with external beam radiotherapy for prostate cancer than conventional DVH's (C-DVH's. Methods The charts of 190 patients treated with external beam radiotherapy with a minimum follow-up of 2 years were reviewed. Six patients (3.2% were found to have RTOG grade 3 GI toxicity, and similarly 6 patients (3.2% were found to have RTOG grade 3 GU toxicity. Average late C-DVH's and BED-DVH's of the bladder and rectum were computed for these patients as well as for matched-pair control patients. For each matched pair the following measures of normalized difference in the DVH's were computed: (a δAUC = (Area Under Curve [AUC] in grade 3 patient – AUC in grade 0 patient/(AUC in grade 0 patient and (b δV60 = (Percent volume receiving = 60 Gy [V60] in grade 3 patient – V60 in grade 0 patient/(V60 in grade 0 patient. Results As expected, the grade 3 curve is to the right of and above the grade 0 curve for all four sets of average DVH's – suggesting that both the C-DVH and the BED-DVH can be used for predicting late toxicity. δAUC was higher for the BED-DVH's than for the C-DVH's – 0.27 vs 0.23 (p = 0.036 for the rectum and 0.24 vs 0.20 (p = 0.065 for the bladder. δV60 was also higher for the BED-DVH's than for the C-DVH's – 2.73 vs 1.49 for the rectum (p = 0.021 and 1.64 vs 0.71 (p = 0.021 for the bladder. Conclusions When considering well-established dosimetric endpoints used in evaluating treatment plans, BED-DVH's for the rectum and bladder correlate better with late toxicity than C-DVH's and should be considered when attempting to minimize late GI and GU toxicity after external beam radiotherapy for prostate cancer.

  7. Systematic review of dose-volume parameters in the prediction of esophagitis in thoracic radiotherapy

    International Nuclear Information System (INIS)

    Rose, Jim; Rodrigues, George; Yaremko, Brian; Lock, Michael; D'Souza, David

    2009-01-01

    Purpose: With dose escalation and increasing use of concurrent chemoradiotherapy, radiation esophagitis (RE) remains a common treatment-limiting acute side effect in the treatment of thoracic malignancies. The advent of 3DCT planning has enabled investigators to study esophageal dose-volume histogram (DVH) parameters as predictors of RE. The purpose of this study was to assess published dosimetric parameters and toxicity data systematically in order to define reproducible predictors of RE, both for potential clinical use, and to provide recommendations for future research in the field. Materials and methods: We performed a systematic literature review of published studies addressing RE in the treatment of lung cancer and thymoma. Our search strategy included a variety of electronic medical databases, textbooks and bibliographies. Both prospective and retrospective clinical studies were included. Information relating to the relationship among measured dosimetric parameters, patient demographics, tumor characteristics, chemotherapy and RE was extracted and analyzed. Results: Eighteen published studies were suitable for analysis. Eleven of these assessed acute RE, while the remainder assessed both acute and chronic RE together. Heterogeneity of esophageal contouring practices, individual differences in information reporting and variability of RE outcome definitions were assessed. Well-described clinical and logistic modeling directly related V 35Gy , V 60Gy and SA 55Gy to clinically significant RE. Conclusions: Several reproducible dosimetric parameters exist in the literature, and these may be potentially relevant in the prediction of RE in the radiotherapy of thoracic malignancies. Further clarification of the predictive relationship between such standardized dosimetric parameters and observed RE outcomes is essential to develop efficient radiation treatment planning in locally advanced NSCLC in the modern concurrent chemotherapy and image-guided IMRT era.

  8. Dose-volume modeling of salivary function in patients with head-and-neck cancer receiving radiotherapy

    International Nuclear Information System (INIS)

    Blanco, Angel I.; Chao, K.S. Clifford; El Naqa, Issam; Franklin, Gregg E.; Zakarian, Konstantin; Vicic, Milos; Deasy, Joseph O.

    2005-01-01

    Purpose: We investigated the factors that affect salivary function after head-and-neck radiotherapy (RT), including parotid gland dose-volume effects, potential compensation by less-irradiated gland tissue, and functional recovery over time. Methods and Materials: Sixty-five patients with head-and-neck tumors were enrolled in a prospective salivary function study. RT was delivered using intensity-modulated RT (n = 45), forward-planning three-dimensional conformal RT (n = 14), or three-dimensional conformal RT with an intensity-modulated RT boost (n = 6). Whole salivary flow was measured before therapy and at 6 months (n = 61) and 12 months (n = 31) after RT. A wide variety of dose-volume models to predict post-RT salivary function were tested. Xerostomia was defined according to the subjective, objective, management, analytic (SOMA) criteria as occurring when posttreatment salivary function was s ] = 0.46, p s = 0.73), stimulated saliva flow at 12 months (R s = 0.54), and quality-of-life score at 6 months (R s = 0.35) after RT. Conclusion: Stimulated parotid salivary gland dose-volume models strongly correlated with both stimulated salivary function and quality-of-life scores at 6 months after RT. The mean stimulated saliva flow rates improved from 6 to 12 months after RT. Salivary function, in each gland, appeared to be lost exponentially at a rate of approximately 5%/1 Gy of mean dose. Additional research is necessary to distinguish among the models for use in treatment planning. The incidence of xerostomia was significantly decreased when the mean dose of at least one parotid gland was kept to <25.8 Gy with conventional fractionation. However, even lower mean doses imply increased late salivary function

  9. Towards the elimination of Monte Carlo statistical fluctuation from dose volume histograms for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Sempau, J.; Bielajew, A.F.

    2000-01-01

    The Monte Carlo calculation of dose for radiotherapy treatment planning purposes introduces unavoidable statistical noise into the prediction of dose in a given volume element (voxel). When the doses in these voxels are summed to produce dose volume histograms (DVHs), this noise translates into a broadening of differential DVHs and correspondingly flatter DVHs. A brute force approach would entail calculating dose for long periods of time - enough to ensure that the DVHs had converged. In this paper we introduce an approach for deconvolving the statistical noise from DVHs, thereby obtaining estimates for converged DVHs obtained about 100 times faster than the brute force approach described above. There are two important implications of this work: (a) decisions based upon DVHs may be made much more economically using the new approach and (b) inverse treatment planning or optimization methods may employ Monte Carlo dose calculations at all stages of the iterative procedure since the prohibitive cost of Monte Carlo calculations at the intermediate calculation steps can be practically eliminated. (author)

  10. Dose-volume histogram analysis as predictor of radiation pneumonitis in primary lung cancer patients treated with radiotherapy

    International Nuclear Information System (INIS)

    Fay, Michael; Tan, Alex; Fisher, Richard; Mac Manus, Michael; Wirth, Andrew; Ball, David

    2005-01-01

    Purpose: To determine the relationship between various parameters derived from lung dose-volume histogram analysis and the risk of symptomatic radiation pneumonitis (RP) in patients undergoing radical radiotherapy for primary lung cancer. Methods and Materials: The records of 156 patients with lung cancer who had been treated with radical radiotherapy (≥45 Gy) and for whom dose-volume histogram data were available were reviewed. The incidence of symptomatic RP was correlated with a variety of parameters derived from the dose-volume histogram data, including the volume of lung receiving 10 Gy (V 10 ) through 50 Gy (V 50 ) and the mean lung dose (MLD). Results: The rate of RP at 6 months was 15% (95% confidence interval 9-22%). On univariate analysis, only V 30 (p = 0.036) and MLD (p = 0.043) were statistically significantly related to RP. V 30 correlated highly positively with MLD (r = 0.96, p 30 and MLD can be used to predict the risk of RP in lung cancer patients undergoing radical radiotherapy

  11. Converging stereotactic radiotherapy using kilovoltage X-rays: experimental irradiation of normal rabbit lung and dose-volume analysis with Monte Carlo simulation.

    Science.gov (United States)

    Kawase, Takatsugu; Kunieda, Etsuo; Deloar, Hossain M; Tsunoo, Takanori; Seki, Satoshi; Oku, Yohei; Saitoh, Hidetoshi; Saito, Kimiaki; Ogawa, Eileen N; Ishizaka, Akitoshi; Kameyama, Kaori; Kubo, Atsushi

    2009-10-01

    To validate the feasibility of developing a radiotherapy unit with kilovoltage X-rays through actual irradiation of live rabbit lungs, and to explore the practical issues anticipated in future clinical application to humans through Monte Carlo dose simulation. A converging stereotactic irradiation unit was developed, consisting of a modified diagnostic computed tomography (CT) scanner. A tiny cylindrical volume in 13 normal rabbit lungs was individually irradiated with single fractional absorbed doses of 15, 30, 45, and 60 Gy. Observational CT scanning of the whole lung was performed every 2 weeks for 30 weeks after irradiation. After 30 weeks, histopathologic specimens of the lungs were examined. Dose distribution was simulated using the Monte Carlo method, and dose-volume histograms were calculated according to the data. A trial estimation of the effect of respiratory movement on dose distribution was made. A localized hypodense change and subsequent reticular opacity around the planning target volume (PTV) were observed in CT images of rabbit lungs. Dose-volume histograms of the PTVs and organs at risk showed a focused dose distribution to the target and sufficient dose lowering in the organs at risk. Our estimate of the dose distribution, taking respiratory movement into account, revealed dose reduction in the PTV. A converging stereotactic irradiation unit using kilovoltage X-rays was able to generate a focused radiobiologic reaction in rabbit lungs. Dose-volume histogram analysis and estimated sagittal dose distribution, considering respiratory movement, clarified the characteristics of the irradiation received from this type of unit.

  12. Mechanistic simulation of normal-tissue damage in radiotherapy-implications for dose-volume analyses

    International Nuclear Information System (INIS)

    Rutkowska, Eva; Baker, Colin; Nahum, Alan

    2010-01-01

    A radiobiologically based 3D model of normal tissue has been developed in which complications are generated when 'irradiated'. The aim is to provide insight into the connection between dose-distribution characteristics, different organ architectures and complication rates beyond that obtainable with simple DVH-based analytical NTCP models. In this model the organ consists of a large number of functional subunits (FSUs), populated by stem cells which are killed according to the LQ model. A complication is triggered if the density of FSUs in any 'critical functioning volume' (CFV) falls below some threshold. The (fractional) CFV determines the organ architecture and can be varied continuously from small (series-like behaviour) to large (parallel-like). A key feature of the model is its ability to account for the spatial dependence of dose distributions. Simulations were carried out to investigate correlations between dose-volume parameters and the incidence of 'complications' using different pseudo-clinical dose distributions. Correlations between dose-volume parameters and outcome depended on characteristics of the dose distributions and on organ architecture. As anticipated, the mean dose and V 20 correlated most strongly with outcome for a parallel organ, and the maximum dose for a serial organ. Interestingly better correlation was obtained between the 3D computer model and the LKB model with dose distributions typical for serial organs than with those typical for parallel organs. This work links the results of dose-volume analyses to dataset characteristics typical for serial and parallel organs and it may help investigators interpret the results from clinical studies.

  13. A dose-volume histogram based decision-support system for dosimetric comparison of radiotherapy treatment plans

    International Nuclear Information System (INIS)

    Alfonso, J. C. L.; Herrero, M. A.; Núñez, L.

    2015-01-01

    The choice of any radiotherapy treatment plan is usually made after the evaluation of a few preliminary isodose distributions obtained from different beam configurations. Despite considerable advances in planning techniques, such final decision remains a challenging task that would greatly benefit from efficient and reliable assessment tools. For any dosimetric plan considered, data on dose-volume histograms supplied by treatment planning systems are used to provide estimates on planning target coverage as well as on sparing of organs at risk and the remaining healthy tissue. These partial metrics are then combined into a dose distribution index (DDI), which provides a unified, easy-to-read score for each competing radiotherapy plan. To assess the performance of the proposed scoring system, DDI figures for fifty brain cancer patients were retrospectively evaluated. Patients were divided in three groups depending on tumor location and malignancy. For each patient, three tentative plans were designed and recorded during planning, one of which was eventually selected for treatment. We thus were able to compare the plans with better DDI scores and those actually delivered. When planning target coverage and organs at risk sparing are considered as equally important, the tentative plan with the highest DDI score is shown to coincide with that actually delivered in 32 of the 50 patients considered. In 15 (respectively 3) of the remaining 18 cases, the plan with highest DDI value still coincides with that actually selected, provided that organs at risk sparing is given higher priority (respectively, lower priority) than target coverage. DDI provides a straightforward and non-subjective tool for dosimetric comparison of tentative radiotherapy plans. In particular, DDI readily quantifies differences among competing plans with similar-looking dose-volume histograms and can be easily implemented for any tumor type and localization, irrespective of the planning system and

  14. Radiation Dose-Volume Effects in the Brain

    International Nuclear Information System (INIS)

    Lawrence, Yaacov Richard; Li, X. Allen; El Naqa, Issam; Hahn, Carol A.; Marks, Lawrence B.; Merchant, Thomas E.; Dicker, Adam P.

    2010-01-01

    We have reviewed the published data regarding radiotherapy (RT)-induced brain injury. Radiation necrosis appears a median of 1-2 years after RT; however, cognitive decline develops over many years. The incidence and severity is dose and volume dependent and can also be increased by chemotherapy, age, diabetes, and spatial factors. For fractionated RT with a fraction size of 80 Gy. For large fraction sizes (≥2.5 Gy), the incidence and severity of toxicity is unpredictable. For single fraction radiosurgery, a clear correlation has been demonstrated between the target size and the risk of adverse events. Substantial variation among different centers' reported outcomes have prevented us from making toxicity-risk predictions. Cognitive dysfunction in children is largely seen for whole brain doses of ≥18 Gy. No substantial evidence has shown that RT induces irreversible cognitive decline in adults within 4 years of RT.

  15. Outcomes of visual acuity in carbon ion radiotherapy: Analysis of dose-volume histograms and prognostic factors

    International Nuclear Information System (INIS)

    Hasegawa, Azusa; Mizoe, Jun-etsu; Mizota, Atsushi; Tsujii, Hirohiko

    2006-01-01

    Purpose: To analyze the tolerance dose for retention of visual acuity in patients with head-and-neck tumors treated with carbon ion radiotherapy. Methods and Materials: From June 1994 to March 2000, 163 patients with tumors in the head and neck or skull base region were treated with carbon ion radiotherapy. Analysis was performed on 54 optic nerves (ONs) corresponding to 30 patients whose ONs had been included in the irradiated volume. These patients showed no evidence of visual impairment due to other factors and had a follow-up period of >4 years. All patients had been informed of the possibility of visual impairment before treatment. We evaluated the dose-complication probability and the prognostic factors for the retention of visual acuity in carbon ion radiotherapy, using dose-volume histograms and multivariate analysis. Results: The median age of 30 patients (14 men, 16 women) was 57.2 years. Median prescribed total dose was 56.0 gray equivalents (GyE) at 3.0-4.0 GyE per fraction per day (range, 48-64 GyE; 16-18 fractions; 4-6 weeks). Of 54 ONs that were analyzed, 35 had been irradiated with max ]) resulting in no visual loss. Conversely, 11 of the 19 ONs (58%) irradiated with >57 GyE (D max ) suffered a decrease of visual acuity. In all of these cases, the ONs had been involved in the tumor before carbon ion radiotherapy. In the multivariate analysis, a dose of 20% of the volume of the ON (D 2 ) was significantly associated with visual loss. Conclusions: The occurrence of visual loss seems to be correlated with a delivery of >60 GyE to 20% of the volume of the ON

  16. Converging Stereotactic Radiotherapy Using Kilovoltage X-Rays: Experimental Irradiation of Normal Rabbit Lung and Dose-Volume Analysis With Monte Carlo Simulation

    International Nuclear Information System (INIS)

    Kawase, Takatsugu; Kunieda, Etsuo; Deloar, Hossain M.; Tsunoo, Takanori; Seki, Satoshi; Oku, Yohei; Saitoh, Hidetoshi; Saito, Kimiaki; Ogawa, Eileen N.; Ishizaka, Akitoshi; Kameyama, Kaori; Kubo, Atsushi

    2009-01-01

    Purpose: To validate the feasibility of developing a radiotherapy unit with kilovoltage X-rays through actual irradiation of live rabbit lungs, and to explore the practical issues anticipated in future clinical application to humans through Monte Carlo dose simulation. Methods and Materials: A converging stereotactic irradiation unit was developed, consisting of a modified diagnostic computed tomography (CT) scanner. A tiny cylindrical volume in 13 normal rabbit lungs was individually irradiated with single fractional absorbed doses of 15, 30, 45, and 60 Gy. Observational CT scanning of the whole lung was performed every 2 weeks for 30 weeks after irradiation. After 30 weeks, histopathologic specimens of the lungs were examined. Dose distribution was simulated using the Monte Carlo method, and dose-volume histograms were calculated according to the data. A trial estimation of the effect of respiratory movement on dose distribution was made. Results: A localized hypodense change and subsequent reticular opacity around the planning target volume (PTV) were observed in CT images of rabbit lungs. Dose-volume histograms of the PTVs and organs at risk showed a focused dose distribution to the target and sufficient dose lowering in the organs at risk. Our estimate of the dose distribution, taking respiratory movement into account, revealed dose reduction in the PTV. Conclusions: A converging stereotactic irradiation unit using kilovoltage X-rays was able to generate a focused radiobiologic reaction in rabbit lungs. Dose-volume histogram analysis and estimated sagittal dose distribution, considering respiratory movement, clarified the characteristics of the irradiation received from this type of unit.

  17. Experimental validation of heterogeneity-corrected dose-volume prescription on respiratory-averaged CT images in stereotactic body radiotherapy for moving tumors

    International Nuclear Information System (INIS)

    Nakamura, Mitsuhiro; Miyabe, Yuki; Matsuo, Yukinori; Kamomae, Takeshi; Nakata, Manabu; Yano, Shinsuke; Sawada, Akira; Mizowaki, Takashi; Hiraoka, Masahiro

    2012-01-01

    The purpose of this study was to experimentally assess the validity of heterogeneity-corrected dose-volume prescription on respiratory-averaged computed tomography (RACT) images in stereotactic body radiotherapy (SBRT) for moving tumors. Four-dimensional computed tomography (CT) data were acquired while a dynamic anthropomorphic thorax phantom with a solitary target moved. Motion pattern was based on cos (t) with a constant respiration period of 4.0 sec along the longitudinal axis of the CT couch. The extent of motion (A 1 ) was set in the range of 0.0–12.0 mm at 3.0-mm intervals. Treatment planning with the heterogeneity-corrected dose-volume prescription was designed on RACT images. A new commercially available Monte Carlo algorithm of well-commissioned 6-MV photon beam was used for dose calculation. Dosimetric effects of intrafractional tumor motion were then investigated experimentally under the same conditions as 4D CT simulation using the dynamic anthropomorphic thorax phantom, films, and an ionization chamber. The passing rate of γ index was 98.18%, with the criteria of 3 mm/3%. The dose error between the planned and the measured isocenter dose in moving condition was within ± 0.7%. From the dose area histograms on the film, the mean ± standard deviation of the dose covering 100% of the cross section of the target was 102.32 ± 1.20% (range, 100.59–103.49%). By contrast, the irradiated areas receiving more than 95% dose for A 1 = 12 mm were 1.46 and 1.33 times larger than those for A 1 = 0 mm in the coronal and sagittal planes, respectively. This phantom study demonstrated that the cross section of the target received 100% dose under moving conditions in both the coronal and sagittal planes, suggesting that the heterogeneity-corrected dose-volume prescription on RACT images is acceptable in SBRT for moving tumors.

  18. Finding dose-volume constraints to reduce late rectal toxicity following 3D-conformal radiotherapy (3D-CRT) of prostate cancer

    International Nuclear Information System (INIS)

    Greco, Carlo; Mazzetta, Chiara; Cattani, Federica; Tosi, Giampiero; Castiglioni, Simona; Fodor, Andrei; Orecchia, Roberto

    2003-01-01

    Background and purpose: The rectum is known to display a dose-volume effect following high-dose 3D-conformal radiotherapy (3D-CRT). The aim of the study is to search for significant dose-volume combinations with the specific treatment technique and patient set-up currently used in our institution. Patients and methods: We retrospectively analyzed the dose-volume histograms (DVH) of 135 patients with stage T1b-T3b prostate cancer treated consecutively with 3D-CRT between 1996 and 2000 to a total dose of 76 Gy. The median follow-up was 28 months (range 12-62). All late rectal complications were scored using RTOG criteria. Time to late toxicity was assessed using the Kaplan-Meyer method. The association between variables at baseline and ≥2 rectal toxicity was tested using χ 2 test or Fisher's exact test. A multivariate analysis using logistic regression was performed. Results: Late rectal toxicity grade ≥2 was observed in 24 of the 135 patients (17.8%). A 'grey area' of increased risk has been identified. Average DVHs of the bleeding and non-bleeding patients were generated. The area under the percent volume DVH for the rectum of the bleeding patients was significantly higher than that of patients without late rectal toxicity. On multivariate analysis the correlation between the high risk DVHs and late rectal bleeding was confirmed. Conclusions: The present analysis confirms the role of the rectal DVH as a tool to discriminate patients undergoing high-dose 3D-CRT into a low and a high risk of developing late rectal bleeding. Based on our own results and taking into account the data published in the literature, we have been able to establish new dose-volume constraints for treatment planning: if possible, the percentage of rectal volume exposed to 40, 50, 60, 72 and 76 Gy should be limited to 60, 50, 25, 15 and 5%, respectively

  19. Prostate position variability and dose-volume histograms in radiotherapy for prostate cancer with full and empty bladder

    International Nuclear Information System (INIS)

    Pinkawa, Michael; Asadpour, Branka; Gagel, Bernd; Piroth, Marc D.; Holy, Richard; Eble, Michael J.

    2006-01-01

    Purpose: To evaluate prostate position variability and dose-volume histograms in prostate radiotherapy with full bladder (FB) and empty bladder (EB). Methods and Materials: Thirty patients underwent planning computed tomography scans in a supine position with FB and EB before and after 4 and 8 weeks of radiation therapy. The scans were matched by alignment of pelvic bones. Displacements of the prostate/seminal vesicle organ borders and center of mass were determined. Treatment plans (FB vs. EB) were compared. Results: Compared with the primary scan, FB volume varied more than EB volume (standard deviation, 106 cm 3 vs. 47 cm 3 ), but the prostate/seminal vesicle center of mass position variability was the same (>3 mm deviation in right-left, anterior-posterior, and superior-inferior directions in 0, 41%, and 33%, respectively, with FB vs. 0, 44%, and 33% with EB). The bladder volume treated with 90% of the prescription dose was significantly larger with EB (39% ± 14% vs. 22% ± 10%; p < 0.01). Bowel loops received ≥90% of prescription dose in 37% (3% with FB; p < 0.01). Conclusion: Despite the larger variability of bladder filling, prostate position stability was the same with FB compared with EB. An increased amount of bladder volume in the high-dose region and a higher dose to bowel loops result from treatment plans with EB

  20. Dysphagia after definitive radiotherapy for head and neck cancer. Correlation of dose-volume parameters of the pharyngeal constrictor muscles

    Energy Technology Data Exchange (ETDEWEB)

    Deantonio, L.; Masini, L. [University Hospital ' Maggiore della Carita' , Novara (Italy). Radiotherapy; Brambilla, M. [University Hospital ' Maggiore della Carita' , Novara (Italy). Medical Physics; Pia, F. [University Hospital ' Maggiore della Carita' , Novara (Italy). Otolaryngology; University of ' Piemonte Orientale' , Novara (Italy). Dept. of Medical Sciences; Krengli, M. [University Hospital ' Maggiore della Carita' , Novara (Italy). Radiotherapy; University of ' Piemonte Orientale' , Novara (Italy). Dept. of Translational Medicine and BRMA

    2013-03-15

    Background: Dysphagia is a complication of head and neck cancer patients undergoing radiotherapy (RT). We analysed frequency and severity of swallowing dysfunction and correlated these findings with dose-volume histograms (DVHs) of the pharyngeal constrictor muscles. Methods: A total of 50 patients treated by radical RT were enrolled. DVHs of constrictor muscles were correlated with acute and late dysphagia and with the items of three quality of life questionnaires. Results: Mean dose to superior and middle constrictor muscles (SCM, MCM), partial volume of SCM and MCM receiving a dose {>=} 50 Gy dose to the whole constrictor muscles {>=} 60 Gy and tumour location were associated to late dysphagia at univariate analysis. Mean dose to the MCM was the only statistically significant predictor of late dysphagia at the multivariable analysis. Conclusion: The study shows a significant relationship between long-term dysphagia and mean doses to SCM, MCM, whole constrictor muscles, and oropharyngeal tumour. This finding suggests a potential advantage in reducing the RT dose to swallowing structures to avoid severe dysphagia. (orig.)

  1. Dysphagia after definitive radiotherapy for head and neck cancer. Correlation of dose-volume parameters of the pharyngeal constrictor muscles

    International Nuclear Information System (INIS)

    Deantonio, L.; Masini, L.; Brambilla, M.; Pia, F.; University of 'Piemonte Orientale', Novara; Krengli, M.; University of 'Piemonte Orientale', Novara

    2013-01-01

    Background: Dysphagia is a complication of head and neck cancer patients undergoing radiotherapy (RT). We analysed frequency and severity of swallowing dysfunction and correlated these findings with dose-volume histograms (DVHs) of the pharyngeal constrictor muscles. Methods: A total of 50 patients treated by radical RT were enrolled. DVHs of constrictor muscles were correlated with acute and late dysphagia and with the items of three quality of life questionnaires. Results: Mean dose to superior and middle constrictor muscles (SCM, MCM), partial volume of SCM and MCM receiving a dose ≥ 50 Gy dose to the whole constrictor muscles ≥ 60 Gy and tumour location were associated to late dysphagia at univariate analysis. Mean dose to the MCM was the only statistically significant predictor of late dysphagia at the multivariable analysis. Conclusion: The study shows a significant relationship between long-term dysphagia and mean doses to SCM, MCM, whole constrictor muscles, and oropharyngeal tumour. This finding suggests a potential advantage in reducing the RT dose to swallowing structures to avoid severe dysphagia. (orig.)

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  3. Intensity modulated radiotherapy for localized prostate cancer: rigid compliance to dose-volume constraints as a warranty of acceptable toxicity?

    International Nuclear Information System (INIS)

    Chen, Michael J; Nadalin, Wladmir; Weltman, Eduardo; Hanriot, Rodrigo M; Luz, Fábio P; Cecílio, Paulo J; Cruz, José C da; Moreira, Frederico R; Santos, Adriana S; Martins, Lidiane C

    2007-01-01

    To report the toxicity after intensity modulated radiotherapy (IMRT) for patients with localized prostate cancer, as a sole treatment or after radical prostatectomy. Between August 2001 and December 2003, 132 patients with prostate cancer were treated with IMRT and 125 were evaluable to acute and late toxicity analysis, after a minimum follow-up time of one year. Clinical and treatment data, including normal tissue dose-volume histogram (DVH) constraints, were reviewed. Gastro-intestinal (GI) and genito-urinary (GU) signs and symptoms were evaluated according to the Radiation Therapy Oncology Group (RTOG) toxicity scales. Median prescribed dose was 76 Gy. Median follow-up time was of 26.1 months. From the 125 patients, 73 (58.4%) presented acute Grade 1 or Grade 2 GI and 97 (77.2%) presented acute Grade 1 or Grade 2 GU toxicity. Grade 3 GI acute toxicity occurred in only 2 patients (1.6%) and Grade 3 GU acute toxicity in only 3 patients (2.4%). Regarding Grade 1 and 2 late toxicity, 26 patients (20.8%) and 21 patients (16.8%) presented GI and GU toxicity, respectively. Grade 2 GI late toxicity occurred in 6 patients (4.8%) and Grade 2 GU late toxicity in 4 patients (3.2%). None patient presented any Grade 3 or higher late toxicity. Non-conformity to DVH constraints occurred in only 11.2% of treatment plans. On univariate analysis, no significant risk factor was identified for Grade 2 GI late toxicity, but mean dose delivered to the PTV was associated to higher Grade 2 GU late toxicity (p = 0.042). IMRT is a well tolerable technique for routine treatment of localized prostate cancer, with short and medium-term acceptable toxicity profiles. According to the data presented here, rigid compliance to DHV constraints might prevent higher incidences of normal tissue complication

  4. A prospective evaluation of hippocampal radiation dose volume effects and memory deficits following cranial irradiation.

    Science.gov (United States)

    Ma, Ting Martin; Grimm, Jimm; McIntyre, Riley; Anderson-Keightly, Heather; Kleinberg, Lawrence R; Hales, Russell K; Moore, Joseph; Vannorsdall, Tracy; Redmond, Kristin J

    2017-11-01

    To prospectively evaluate hippocampal radiation dose volume effects and memory decline following cranial irradiation. Effects of hippocampal radiation over a wide range of doses were investigated by combining data from three prospective studies. In one, adults with small cell lung cancer received hippocampal-avoidance prophylactic cranial irradiation. In the other two, adults with glioblastoma multiforme received neural progenitor cell sparing radiation or no sparing with extra dose delivered to subventricular zone. Memory was measured by the Hopkins Verbal Learning Test-Revised Delayed Recall (HVLT-R DR) at 6 months after radiation. Dose-volume histograms were generated and dose-response data were fitted to a nonlinear model. Of 60 patients enrolled, 30 were analyzable based on HVLT-R DR testing completion status, baseline HVLT-R DR and intracranial metastasis/recurrence or prior hippocampal resection status. We observed a dose-response of radiation to the hippocampus with regard to decline in HVLT-R DR. D50% of the bilateral hippocampi of 22.1 Gy is associated with 20% risk of decline. This prospective study demonstrates an association between hippocampal dose volume effects and memory decline measured by HVLT-R DR over a wide dose range. These data support a potential benefit of hippocampal sparing and encourage continued trial enrollment. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Quantitative dose-volume response analysis of changes in parotid gland function after radiotherapy in the head-and-neck region

    International Nuclear Information System (INIS)

    Roesink, Judith M.; Moerland, Marinus A.; Battermann, Jan J.; Hordijk, Gerrit Jan; Terhaard, Chris H.J.

    2001-01-01

    Purpose: To study the radiation tolerance of the parotid glands as a function of dose and volume irradiated. Methods and Materials: One hundred eight patients treated with primary or postoperative radiotherapy for various malignancies in the head-and-neck region were prospectively evaluated. Stimulated parotid flow rate was measured before radiotherapy and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from CT-based treatment planning. The normal tissue complication probability model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow rate 50 (the dose to the whole organ leading to a complication probability of 50%) was found to be 31, 35, and 39 Gy at 6 weeks, 6 months, and 1 year postradiotherapy, respectively. The volume dependency parameter n was around 1, which means that the mean parotid dose correlates best with the observed complications. There was no steep dose-response curve (m=0.45 at 1 year postradiotherapy). Conclusions: This study on dose/volume/parotid gland function relationships revealed a linear correlation between postradiotherapy flow ratio and parotid gland dose and a strong volume dependency. No threshold dose was found. Recovery of parotid gland function was shown at 6 months and 1 year after radiotherapy. In radiation planning, attempts should be made to achieve a mean parotid gland dose at least below 39 Gy (leading to a complication probability of 50%)

  6. Absence of multiple local minima effects in intensity modulated optimization with dose-volume constraints

    Energy Technology Data Exchange (ETDEWEB)

    Llacer, Jorge [EC Engineering Consultants, LLC 130, Forest Hill Drive, Los Gatos, CA (United States); Deasy, Joseph O [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO (United States); Bortfeld, Thomas R [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, 30 Fruit Street, Boston, MA (United States); Solberg, Timothy D [Department of Radiation Oncology, University of California, Los Angeles, CA (United States); Promberger, Claus [BrainLAB AG, Ammerthalstrasse 8, 85551 Heimstetten (Germany)

    2003-01-21

    This paper reports on the analysis of intensity modulated radiation treatment optimization problems in the presence of non-convex feasible parameter spaces caused by the specification of dose-volume constraints for the organs-at-risk (OARs). The main aim was to determine whether the presence of those non-convex spaces affects the optimization of clinical cases in any significant way. This was done in two phases: (1) Using a carefully designed two-dimensional mathematical phantom that exhibits two controllable minima and with randomly initialized beamlet weights, we developed a methodology for exploring the nature of the convergence characteristics of quadratic cost function optimizations (deterministic or stochastic). The methodology is based on observing the statistical behaviour of the residual cost at the end of optimizations in which the stopping criterion is progressively more demanding and carrying out those optimizations to very small error changes per iteration. (2) Seven clinical cases were then analysed with dose-volume constraints that are stronger than originally used in the clinic. The clinical cases are two prostate cases differently posed, a meningioma case, two head-and-neck cases, a spleen case and a spine case. Of the 14 different sets of optimizations (with and without the specification of maximum doses allowed for the OARs), 12 fail to show any effect due to the existence of non-convex feasible spaces. The remaining two sets of optimizations show evidence of multiple minima in the solutions, but those minima are very close to each other in cost and the resulting treatment plans are practically identical, as measured by the quality of the dose-volume histograms (DVHs). We discuss the differences between fluence maps resulting from those similar treatment plans. We provide a possible reason for the observed results and conclude that, although the study is necessarily limited, the annealing characteristics of a simulated annealing method may not be

  7. Incidence of late rectal bleeding in high-dose conformal radiotherapy of prostate cancer using equivalent uniform dose-based and dose-volume-based normal tissue complication probability models

    International Nuclear Information System (INIS)

    Soehn, Matthias; Yan Di; Liang Jian; Meldolesi, Elisa; Vargas, Carlos; Alber, Markus

    2007-01-01

    Purpose: Accurate modeling of rectal complications based on dose-volume histogram (DVH) data are necessary to allow safe dose escalation in radiotherapy of prostate cancer. We applied different equivalent uniform dose (EUD)-based and dose-volume-based normal tissue complication probability (NTCP) models to rectal wall DVHs and follow-up data for 319 prostate cancer patients to identify the dosimetric factors most predictive for Grade ≥ 2 rectal bleeding. Methods and Materials: Data for 319 patients treated at the William Beaumont Hospital with three-dimensional conformal radiotherapy (3D-CRT) under an adaptive radiotherapy protocol were used for this study. The following models were considered: (1) Lyman model and (2) logit-formula with DVH reduced to generalized EUD (3) serial reconstruction unit (RU) model (4) Poisson-EUD model, and (5) mean dose- and (6) cutoff dose-logistic regression model. The parameters and their confidence intervals were determined using maximum likelihood estimation. Results: Of the patients, 51 (16.0%) showed Grade 2 or higher bleeding. As assessed qualitatively and quantitatively, the Lyman- and Logit-EUD, serial RU, and Poisson-EUD model fitted the data very well. Rectal wall mean dose did not correlate to Grade 2 or higher bleeding. For the cutoff dose model, the volume receiving > 73.7 Gy showed most significant correlation to bleeding. However, this model fitted the data more poorly than the EUD-based models. Conclusions: Our study clearly confirms a volume effect for late rectal bleeding. This can be described very well by the EUD-like models, of which the serial RU- and Poisson-EUD model can describe the data with only two parameters. Dose-volume-based cutoff-dose models performed worse

  8. Effect of tumor dose, volume and overall treatment time on local control after radiochemotherapy including MRI guided brachytherapy of locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Tanderup, Kari; Fokdal, Lars Ulrik; Sturdza, Alina

    2016-01-01

    -center patient series (retroEMBRACE). Materials and methods This study analyzed 488 locally advanced cervical cancer patients treated with external beam radiotherapy ± chemotherapy combined with IGABT. Brachytherapy contouring and reporting was according to ICRU/GEC-ESTRO recommendations. The Cox Proportional...... Hazards model was applied to analyze the effect on local control of dose-volume metrics as well as overall treatment time (OTT), dose rate, chemotherapy, and tumor histology. Results With a median follow up of 46 months, 43 local failures were observed. Dose (D90) to the High Risk Clinical Target Volume...

  9. Analysis of dose volume histogram parameters to estimate late bladder and rectum complications after high-dose (70-78 Gy) conformal radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Boersma, L.J.; Brink, M. van den; Bruce, A.; Gras, L.; Velde, A. te; Lebesque, J.V.

    1997-01-01

    Purpose: To investigate whether Dose Volume Histogram (DVH) parameters can be used to identify risk groups for developing late gastrointestinal (GI) and genitourinary (GU) complications after conformal radiotherapy for prostate cancer, and to examine the effect of using different morbidity scoring systems on the results of these analyses. Materials and Methods: DVH parameters were analyzed for 130 patients with localized prostate cancer, treated with conformal radiotherapy in a dose-escalating protocol (70-78 Gy, 2 Gy per fraction). The incidence of late (> 6 months) GI and GU complications was scored based on questionnaires and classified using the RTOG/EORTC and the SOMA/LENT scoring system. Moreover, patients were classified as being a rectal bleeder or no rectal bleeder and a distinction was made between non-severe and severe (requiring one or more laser treatments) rectal bleeding. The median follow-up time was 22 months. It was investigated whether the relative and absolute rectal wall volumes, irradiated to various dose levels (≥ 60 Gy, ≥ 65 Gy, ≥ 70 Gy and ≥ 75 Gy) were correlated with the observed actuarial incidences of GI complications. First, the analysis was performed using volume as a continuous variable. Subsequently, for each dose level in the DVH the rectal wall volumes were dichotomized using different volumes as cut-off levels. Twenty cut-off levels were tested on their ability to discriminate between high and low risk for developing GI complications (Fig.). The relationship between bladder wall volumes irradiated to various dose levels and observed actuarial GU complications was investigated using the absolute bladder wall volumes, measured as a continuous variable. For both GI and GU complications, the role of the prescribed radiation dose and the maximum radiation dose in the rectal and bladder wall was analyzed as well. Results: None of the DVH parameters of the rectal wall was significantly correlated with the actuarial incidences of

  10. Dose-volume effects in the rat cervical spinal cord after proton irradiation

    International Nuclear Information System (INIS)

    Bijl, Hendrik P.; Vuijk, Peter van; Coppes, Rob P.; Schippers, Jacobus M.; Konings, Antonius W.T.; Kogel, Albert J. van der

    2002-01-01

    Purpose: To estimate dose-volume effects in the rat cervical spinal cord with protons. Methods and Materials: Wistar rats were irradiated on the cervical spinal cord with a single fraction of unmodulated protons (150-190 MeV) using the shoot through method, which employs the plateau of the depth-dose profile rather than the Bragg peak. Four different lengths of the spinal cord (2, 4, 8, and 20 mm) were irradiated with variable doses. The endpoint for estimating dose-volume effects was paralysis of fore or hind limbs. Results: The results obtained with a high-precision proton beam showed a marginal increase of ED 50 when decreasing the irradiated cord length from 20 mm (ED 50 = 20.4 Gy) to 8 mm (ED 50 = 24.9 Gy), but a steep increase in ED 50 when further decreasing the length to 4 mm (ED 50 = 53.7 Gy) and 2 mm (ED 50 = 87.8 Gy). These results generally confirm data obtained previously in a limited series with 4-6-MV photons, and for the first time it was possible to construct complete dose-response curves down to lengths of 2 mm. At higher ED 50 values and shorter lengths irradiated, the latent period to paralysis decreased from 125 to 60 days. Conclusions: Irradiation of variable lengths of rat cervical spinal cord with protons showed steeply increasing ED 50 values for lengths of less than 8 mm. These results suggest the presence of a critical migration distance of 2-3 mm for cells involved in regeneration processes

  11. Dose-Volume Parameters of the Corpora Cavernosa Do Not Correlate With Erectile Dysfunction After External Beam Radiotherapy for Prostate Cancer: Results From a Dose-Escalation Trial

    International Nuclear Information System (INIS)

    Wielen, Gerard J. van der; Hoogeman, Mischa S.; Dohle, Gert R.; Putten, Wim L.J. van; Incrocci, Luca

    2008-01-01

    Purpose: To analyze the correlation between dose-volume parameters of the corpora cavernosa and erectile dysfunction (ED) after external beam radiotherapy (EBRT) for prostate cancer. Methods and Materials: Between June 1997 and February 2003, a randomized dose-escalation trial comparing 68 Gy and 78 Gy was conducted. Patients at our institute were asked to participate in an additional part of the trial evaluating sexual function. After exclusion of patients with less than 2 years of follow-up, ED at baseline, or treatment with hormonal therapy, 96 patients were eligible. The proximal corpora cavernosa (crura), the superiormost 1-cm segment of the crura, and the penile bulb were contoured on the planning computed tomography scan and dose-volume parameters were calculated. Results: Two years after EBRT, 35 of the 96 patients had developed ED. No statistically significant correlations between ED 2 years after EBRT and dose-volume parameters of the crura, the superiormost 1-cm segment of the crura, or the penile bulb were found. The few patients using potency aids typically indicated to have ED. Conclusion: No correlation was found between ED after EBRT for prostate cancer and radiation dose to the crura or penile bulb. The present study is the largest study evaluating the correlation between ED and radiation dose to the corpora cavernosa after EBRT for prostate cancer. Until there is clear evidence that sparing the penile bulb or crura will reduce ED after EBRT, we advise to be careful in sparing these structures, especially when this involves reducing treatment margins

  12. SU-F-T-347: An Absolute Dose-Volume Constraint Based Deterministic Optimization Framework for Multi-Co60 Source Focused Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liang, B; Liu, B; Li, Y; Guo, B; Xu, X; Wei, R; Zhou, F [Beihang University, Beijing, Beijing (China); Wu, Q [Duke University Medical Center, Durham, NC (United States)

    2016-06-15

    Purpose: Treatment plan optimization in multi-Co60 source focused radiotherapy with multiple isocenters is challenging, because dose distribution is normalized to maximum dose during optimization and evaluation. The objective functions are traditionally defined based on relative dosimetric distribution. This study presents an alternative absolute dose-volume constraint (ADC) based deterministic optimization framework (ADC-DOF). Methods: The initial isocenters are placed on the eroded target surface. Collimator size is chosen based on the area of 2D contour on corresponding axial slice. The isocenter spacing is determined by adjacent collimator sizes. The weights are optimized by minimizing the deviation from ADCs using the steepest descent technique. An iterative procedure is developed to reduce the number of isocenters, where the isocenter with lowest weight is removed without affecting plan quality. The ADC-DOF is compared with the genetic algorithm (GA) using the same arbitrary shaped target (254cc), with a 15mm margin ring structure representing normal tissues. Results: For ADC-DOF, the ADCs imposed on target and ring are (D100>10Gy, D50,10, 0<12Gy, 15Gy and 20Gy) and (D40<10Gy). The resulting D100, 50, 10, 0 and D40 are (9.9Gy, 12.0Gy, 14.1Gy and 16.2Gy) and (10.2Gy). The objectives of GA are to maximize 50% isodose target coverage (TC) while minimize the dose delivered to the ring structure, which results in 97% TC and 47.2% average dose in ring structure. For ADC-DOF (GA) techniques, 20 out of 38 (10 out of 12) initial isocenters are used in the final plan, and the computation time is 8.7s (412.2s) on an i5 computer. Conclusion: We have developed a new optimization technique using ADC and deterministic optimization. Compared with GA, ADC-DOF uses more isocenters but is faster and more robust, and achieves a better conformity. For future work, we will focus on developing a more effective mechanism for initial isocenter determination.

  13. Association of anorectal dose-volume histograms and impaired fecal continence after 3D conformal radiotherapy for carcinoma of the prostate

    International Nuclear Information System (INIS)

    Vordermark, Dirk; Schwab, Michael; Ness-Dourdoumas, Rhea; Sailer, Marco; Flentje, Michael; Koelbl, Oliver

    2003-01-01

    Purpose: The late toxicity of fecal incontinence after pelvic radiotherapy is now frequently recognized but the etiology poorly understood. We therefore investigated associations between dose-volume histogram (DVH) parameters of the rectum and the anal canal with fecal continence as measured by an established 10-item questionnaire. Methods and materials: Forty-four patients treated for carcinoma of the prostate with 58-72 Gy of 3D conformal radiotherapy between 1995 and 1999 who completed the questionnaire formed the study population. Total continence scores of treated patients obtained 1.5 years (median) after radiotherapy were compared to a control group of 30 patients before radiotherapy. Median, mean, minimum and maximum doses as well as the volume (% and ml) treated to 40, 50, 60 and 70 Gy were determined separately for anal canal and rectum. DVH parameters were correlated with total continence score (Spearman rank test) and patients grouped according to observed continence were compared regarding DVH values (Mann-Whitney U-test). Results: Median fecal continence scores were significantly worse in the irradiated than in the control group (31 vs. 35 of a maximum 36 points). In treated patients, 59%/27%/14% were classified as fully continent, slightly incontinent and severely incontinent. Continence was similar in the 58-to-62-Gy, 66-Gy and 68-to-72-Gy dose groups. No DVH parameter was significantly correlated with total continence score, but severely incontinent patients had a significantly higher minimum dose to the anal canal than fully continent/slightly incontinent, accompanied by portals extending significantly further inferiorly with respect to the ischial tuberosities. Conclusions: Excluding the inferior part of the anal canal from the treated volume in 3D conformal therapy for carcinoma of the prostate appears to be a promising strategy to prevent radiation-induced fecal incontinence

  14. Inclusion of functional information from perfusion SPECT improves predictive value of dose-volume parameters in lung toxicity outcome after radiotherapy for non-small cell lung cancer: A prospective study

    DEFF Research Database (Denmark)

    Farr, Katherina P; Kallehauge, Jesper F; Møller, Ditte S

    2015-01-01

    for corresponding standard parameters, but they were not significantly different from each other. CONCLUSION: SPECT-based functional parameters were better to predict the risk of RP compared to standard CT-based dose-volume parameters. Functional parameters may be useful to guide radiotherapy planning in order...

  15. Weekly Dose-Volume Parameters of Mucosa and Constrictor Muscles Predict the Use of Percutaneous Endoscopic Gastrostomy During Exclusive Intensity-Modulated Radiotherapy for Oropharyngeal Cancer

    International Nuclear Information System (INIS)

    Sanguineti, Giuseppe; Gunn, G. Brandon; Parker, Brent C.; Endres, Eugene J.; Zeng Jing; Fiorino, Claudio

    2011-01-01

    Purpose: To define predictors of percutaneous endoscopic gastrostomy (PEG) use during intensity-modulated radiotherapy (IMRT) for oropharyngeal cancer. Methods and Materials: Data for 59 consecutive patients treated with exclusive IMRT at a single institution were recovered. Of 59 patients, 25 were treated with hyperfractionation (78 Gy, 1.3 Gy per fraction, twice daily; 'HYPER'); and 34 of 59 were treated with a once-daily fractionation schedule (66 Gy, 2.2 Gy per fraction, or 70 Gy, 2 Gy per fraction; 'no-HYPER'). On the basis of symptoms during treatment, a PEG tube could have been placed as appropriate. A number of clinical/dosimetric factors, including the weekly dose-volume histogram of oral mucosa (OM DVHw) and weekly mean dose to constrictors and larynx, were considered. The OM DVHw of patients with and without PEG were compared to assess the most predictive dose-volume combinations. Results: Of 59 patients, 22 needed a PEG tube during treatment (for 15 of 22, ≥3 months). The best cutoff values for OM DVHw were V9.5 Gy/week 3 and V10 Gy/week 3 . At univariate analysis, fractionation, mean weekly dose to OM and superior and middle constrictors, and OM DVHw were strongly correlated with the risk of PEG use. In a stepwise multivariate logistic analysis, OM V9.5 Gy/week (≥64 vs. 3 ) was the most predictive parameter (odds ratio 30.8, 95% confidence interval 3.7-254.2, p = 0.0015), confirmed even in the no-HYPER subgroup (odds ratio 21, 95% CI 2.1 confidence interval 210.1, p = 0.01). Conclusions: The risk of PEG use is drastically reduced when OM V9.5-V10 Gy/week is 3 . These data warrant prospective validation.

  16. Estimation of the incidence of late bladder and rectum complications after high-dose (70-78 Gy) conformal radiotherapy for prostate cancer, using dose-volume histograms

    International Nuclear Information System (INIS)

    Boersma, Liesbeth J.; Brink, Mandy van den; Bruce, Allison M.; Shouman, Tarek; Gras, Luuk; Velde, Annet te; Lebesque, Joos V.

    1998-01-01

    Purpose: To investigate whether Dose-Volume Histogram (DVH) parameters can be used to identify risk groups for developing late gastrointestinal (GI) and genitourinary (GU) complications after conformal radiotherapy for prostate cancer. Methods and Materials: DVH parameters were analyzed for 130 patients with localized prostate cancer, treated with conformal radiotherapy in a dose-escalating protocol (70-78 Gy, 2 Gy per fraction). The incidence of late (>6 months) GI and GU complications was classified using the RTOG/EORTC and the SOMA/LENT scoring system. In addition, GI complications were divided in nonsevere and severe (requiring one or more laser treatments or blood transfusions) rectal bleeding. The median follow-up time was 24 months. We investigated whether rectal and bladder wall volumes, irradiated to various dose levels, correlated with the observed actuarial incidences of GI and GU complications, using volume as a continuous variable. Subsequently, for each dose level in the DVH, the rectal wall volumes were dichotomized using different volumes as cutoff levels. The impact of the total radiation dose, and the maximum radiation dose in the rectal and bladder wall was analyzed as well. Results: The actuarial incidence at 2 years for GI complications ≥Grade II was 14% (RTOG/EORTC) or 20% (SOMA/LENT); for GU complications ≥Grade III 8% (RTOG/EORTC) or 21% (SOMA/LENT). Neither for GI complications ≥Grade II (RTOG/EORTC or SOMA/LENT), nor for GU complications ≥Grade III (RTOG/EORTC or SOMA/LENT), was a significant correlation found between any of the DVH parameters and the actuarial incidence of complications. For severe rectal bleeding (actuarial incidence at 2 years 3%), four consecutive volume cutoff levels were found, which significantly discriminated between high and low risk. A trend was observed that a total radiation dose ≥ 74 Gy (or a maximum radiation dose in the rectal wall >75 Gy) resulted in a higher incidence of severe rectal bleeding (p

  17. Dose-volume analysis of predictors for chronic rectal toxicity after treatment of prostate cancer with adaptive image-guided radiotherapy

    International Nuclear Information System (INIS)

    Vargas, Carlos; Martinez, Alvaro; Kestin, Larry L.; Yan Di; Grills, Inga; Brabbins, Donald S.; Lockman, David M.; Liang Jian; Gustafson, Gary S.; Chen, Peter Y.; Vicini, Frank A.; Wong, John W.

    2005-01-01

    Purpose We analyzed our experience treating localized prostate cancer with image-guided off-line correction with adaptive high-dose radiotherapy (ART) in our Phase II dose escalation study to identify factors predictive of chronic rectal toxicity. Materials and Methods From 1999-2002, 331 patients with clinical stage T1-T3N0M0 prostate cancer were prospectively treated in our Phase II 3D conformal dose escalation ART study to a median dose of 75.6 Gy (range, 63.0-79.2 Gy), minimum dose to confidence limited-planning target volume (cl-PTV) in 1.8 Gy fractions (median isocenter dose = 79.7 Gy). Seventy-four patients (22%) also received neoadjuvant/adjuvant androgen deprivation therapy. A patient-specific cl-PTV was constructed using 5 computed tomography scans and 4 sets of electronic portal images by applying an adaptive process to assure target accuracy and minimize PTV margin. For each case, the rectum (rectal solid) was contoured from the sacroiliac joints or rectosigmoid junction (whichever was higher) to the anal verge or ischial tuberosities (whichever was lower), with a median volume of 81.2 cc. The rectal wall was defined using the rectal solid with an individualized 3-mm wall thickness (median volume = 29.8 cc). Rectal wall dose-volume histogram was used to determine the prescribed dose. Toxicity was quantified using the National Cancer Institute Common Toxicity Criteria 2.0. Multiple dose-volume endpoints were evaluated for their association with chronic rectal toxicity. Results Median follow-up was 1.6 years. Thirty-four patients (crude rate 10.3%) experienced Grade 2 chronic rectal toxicity at a median interval of 1.1 years. Nine patients (crude rate = 2.7%) experienced Grade ≥3 chronic rectal toxicity (1 was Grade 4) at a median interval of 1.2 years. The 3-year rates of Grade ≥2 and Grade ≥3 chronic rectal toxicity were 20% and 4%, respectively. Acute toxicity predicted for chronic: Acute Grade 2-3 rectal toxicity (p 40% respectively. The volume

  18. Clinical evaluation of dose-volume-effect relationship in radiation injury of the brain

    International Nuclear Information System (INIS)

    Saito, Mari

    1990-01-01

    Radiation brain injury, including functional disturbances or morphological changes (brain atrophy, periventricular lucencies or ventricular dilatation), were studied by CT in patients with primary intracranial neoplasms who were followed-up for at least 5 months after receiving radiotherapy. Each of 33 patients with medulloblastoma, pinealregion tumor or malignant lymphoma received a total dose of 40-61 Gy by conventional fractionation using a whole brain irradiation field boosted by a localized field. Of these patients, 19 (58%) developed radiation brain injury. It was concluded that the volume-dose was one of the most important factors influencing the development of radiation brain injury. Age at the time of radiotherapy and time of follow-up after the treatment were also considered to be important factors. (author)

  19. Effect of radiation in radiotherapy

    International Nuclear Information System (INIS)

    Hirata, Hideki; Fujibuchi, Toshio; Saito, Tsutomu

    2013-01-01

    The title subject is easily explained for the deterministic effect, secondary cancer formation and case reports of accidental exposure at radiotherapy. For the deterministic effect, the dose-effect relationship is sigmoidal in normal and cancer tissues, and the more separated are their curves, the more favorable is the radiotherapy. TD 5/5 is the tolerable dose to yield <5% of irreversible radiation injury to the normal tissue within 5 years after the therapy and is generally dose-limiting. The curves are of various shapes depending on the tissue composition that its functional subunit (FSU) is parallel like lobules of the liver, or in series like neuron. Symptoms appear complicated on these factors. Recent development of CT-based therapeutic planning has made it possible to analyze the partial tissue volume to be irradiated and its absorbed dose by the relationship (dose volume histogram, DVH) between the electron density vs CT value regardless to anatomy. The normal tissue complication probability is a model composed from the physical DVH and biological factors of FSU composition and cellular radiation susceptibility, and is a measure of the irreversible late effect manifested in normal tissues. Epidemiology has shown the increased risk of secondary cancer formation by radiotherapy. Children are highly susceptible to this, and in adults undergoing the therapy of a certain cancer, it is known that the risk of radiation carcinogenesis is increased in the particular tissue. There are presented such case reports of accidental excessive exposure at radiotherapy as caused by an inappropriate use of detector, partial loss of data in a therapeutic planning device, reading of reversed MRI image, and too much repeated use of the old-type electric portal imaging device. (T.T.)

  20. Dose-volume histograms for optimization of treatment plans illustrated by the example of oesophagus carcinoma

    International Nuclear Information System (INIS)

    Roth, J.; Huenig, R.; Huegli, C.

    1995-01-01

    Using the example of oesophagus carcinoma, dose-volume histograms for diverse treatment techniques are calculated and judged by means of multiplanar isodose representations. The selected treatment plans are ranked with the aid of the dose-volume histograms. We distinguish the tissue inside and outside of the target volume. The description of the spatial dose distribution in dependence of the different volumes and the respective fractions of the tumor dose therein with the help of dose-volume histograms brings about a correlation between the physical parameters and the biological effects. In addition one has to bear in mind the consequences of measures that influence the reaction and the side-effects of radiotherapy (e.g. chemotherapy), i.e. the recuperation of the tissues that were irradiated intentionally or inevitably. Taking all that into account it is evident that the dose-volume histograms are a powerful tool for assessing the quality of treatment plans. (orig./MG) [de

  1. BEDVH--A method for evaluating biologically effective dose volume histograms: Application to eye plaque brachytherapy implants

    International Nuclear Information System (INIS)

    Gagne, Nolan L.; Leonard, Kara L.; Huber, Kathryn E.; Mignano, John E.; Duker, Jay S.; Laver, Nora V.; Rivard, Mark J.

    2012-01-01

    Purpose: A method is introduced to examine the influence of implant duration T, radionuclide, and radiobiological parameters on the biologically effective dose (BED) throughout the entire volume of regions of interest for episcleral brachytherapy using available radionuclides. This method is employed to evaluate a particular eye plaque brachytherapy implant in a radiobiological context. Methods: A reference eye geometry and 16 mm COMS eye plaque loaded with 103 Pd, 125 I, or 131 Cs sources were examined with dose distributions accounting for plaque heterogeneities. For a standardized 7 day implant, doses to 90% of the tumor volume ( TUMOR D 90 ) and 10% of the organ at risk volumes ( OAR D 10 ) were calculated. The BED equation from Dale and Jones and published α/β and μ parameters were incorporated with dose volume histograms (DVHs) for various T values such as T = 7 days (i.e., TUMOR 7 BED 10 and OAR 7 BED 10 ). By calculating BED throughout the volumes, biologically effective dose volume histograms (BEDVHs) were developed for tumor and OARs. Influence of T, radionuclide choice, and radiobiological parameters on TUMOR BEDVH and OAR BEDVH were examined. The nominal dose was scaled for shorter implants to achieve biological equivalence. Results: TUMOR D 90 values were 102, 112, and 110 Gy for 103 Pd, 125 I, and 131 Cs, respectively. Corresponding TUMOR 7 BED 10 values were 124, 140, and 138 Gy, respectively. As T decreased from 7 to 0.01 days, the isobiologically effective prescription dose decreased by a factor of three. As expected, TUMOR 7 BEDVH did not significantly change as a function of radionuclide half-life but varied by 10% due to radionuclide dose distribution. Variations in reported radiobiological parameters caused TUMOR 7 BED 10 to deviate by up to 46%. Over the range of OAR α/β values, OAR 7 BED 10 varied by up to 41%, 3.1%, and 1.4% for the lens, optic nerve, and lacrimal gland, respectively. Conclusions: BEDVH permits evaluation of the

  2. The Impact of Heart Irradiation on Dose-Volume Effects in the Rat Lung

    International Nuclear Information System (INIS)

    Luijk, Peter van; Faber, Hette; Meertens, Harm; Schippers, Jacobus M.; Langendijk, Johannes A.; Brandenburg, Sytze; Kampinga, Harm H.; Coppes, Robert P. Ph.D.

    2007-01-01

    Purpose: To test the hypothesis that heart irradiation increases the risk of a symptomatic radiation-induced loss of lung function (SRILF) and that this can be well-described as a modulation of the functional reserve of the lung. Methods and Materials: Rats were irradiated with 150-MeV protons. Dose-response curves were obtained for a significant increase in breathing frequency after irradiation of 100%, 75%, 50%, or 25% of the total lung volume, either including or excluding the heart from the irradiation field. A significant increase in the mean respiratory rate after 6-12 weeks compared with 0-4 weeks was defined as SRILF, based on biweekly measurements of the respiratory rate. The critical volume (CV) model was used to describe the risk of SRILF. Fits were done using a maximum likelihood method. Consistency between model and data was tested using a previously developed goodness-of-fit test. Results: The CV model could be fitted consistently to the data for lung irradiation only. However, this fitted model failed to predict the data that also included heart irradiation. Even refitting the model to all data resulted in a significant difference between model and data. These results imply that, although the CV model describes the risk of SRILF when the heart is spared, the model needs to be modified to account for the impact of dose to the heart on the risk of SRILF. Finally, a modified CV model is described that is consistent to all data. Conclusions: The detrimental effect of dose to the heart on the incidence of SRILF can be described by a dose dependent decrease in functional reserve of the lung

  3. Spinal cord tolerance to single-session uniform irradiation in pigs: Implications for a dose-volume effect

    International Nuclear Information System (INIS)

    Medin, Paul M.; Foster, Ryan D.; Kogel, Albert J. van der; Sayre, James W.; McBride, William H.; Solberg, Timothy D.

    2013-01-01

    Background and purpose: This study was performed to test the hypothesis that spinal cord radiosensitivity is significantly modified by uniform versus laterally non-uniform dose distributions. Materials and methods: A uniform dose distribution was delivered to a 4.5–7.0 cm length of cervical spinal cord in 22 mature Yucatan minipigs for comparison with a companion study in which a laterally non-uniform dose was given [1]. Pigs were allocated into four dose groups with mean maximum spinal cord doses of 17.5 ± 0.1 Gy (n = 7), 19.5 ± 0.2 Gy (n = 6), 22.0 ± 0.1 Gy (n = 5), and 24.1 ± 0.2 Gy (n = 4). The study endpoint was motor neurologic deficit determined by a change in gait within one year. Spinal cord sections were stained with a Luxol fast blue/periodic acid Schiff combination. Results: Dose–response curves for uniform versus non-uniform spinal cord irradiation were nearly identical with ED 50 ’s (95% confidence interval) of 20.2 Gy (19.1–25.8) and 20.0 Gy (18.3–21.7), respectively. No neurologic change was observed for either dose distribution when the maximum spinal cord dose was ⩽17.8 Gy while all animals experienced deficits at doses ⩾21.8 Gy. Conclusion: No dose-volume effect was observed in pigs for the dose distributions studied and the endpoint of motor neurologic deficit; however, partial spinal cord irradiation resulted in less debilitating neurologic morbidity and histopathology

  4. Effect of various methods for rectum delineation on relative and absolute dose-volume histograms for prostate IMRT treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Kusumoto, Chiaki [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Ohira, Shingo [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita (Japan); Miyazaki, Masayoshi [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Ueda, Yoshihiro [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Department of Radiation Oncology, Graduate School of Medicine, Osaka University, Suita (Japan); Isono, Masaru [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan); Teshima, Teruki, E-mail: teshima-te@mc.pref.osaka.jp [Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka (Japan)

    2016-07-01

    Several reports have dealt with correlations of late rectal toxicity with rectal dose-volume histograms (DVHs) for high dose levels. There are 2 techniques to assess rectal volume for reception of a specific dose: relative-DVH (R-DVH, %) that indicates relative volume for a vertical axis, and absolute-DVH (A-DVH, cc) with its vertical axis showing absolute volume of the rectum. The parameters of DVH vary depending on the rectum delineation method, but the literature does not present any standardization of such methods. The aim of the present study was to evaluate the effects of different delineation methods on rectal DVHs. The enrollment for this study comprised 28 patients with high-risk localized prostate cancer, who had undergone intensity-modulated radiation therapy (IMRT) with the prescription dose of 78 Gy. The rectum was contoured with 4 different methods using 2 lengths, short (Sh) and long (Lg), and 2 cross sections, rectum (Rec) and rectal wall (Rw). Sh means the length from 1 cm above the seminal vesicles to 1 cm below the prostate and Lg the length from the rectosigmoid junction to the anus. Rec represents the entire rectal volume including the rectal contents and Rw the rectal volume of the area with a wall thickness of 4 mm. We compared dose-volume parameters by using 4 rectal contour methods for the same plan with the R-DVHs as well as the A-DVHs. For the high dose levels, the R-DVH parameters varied widely. The mean of V{sub 70} for Sh-Rw was the highest (19.4%) and nearly twice as high as that for Lg-Rec (10.4%). On the contrary, only small variations were observed in the A-DVH parameters (4.3, 4.3, 5.5, and 5.5 cc for Sh-Rw, Lg-Rw, Sh-Rec, and Lg-Rec, respectively). As for R-DVHs, the parameters of V{sub 70} varied depending on the rectal lengths (Sh-Rec vs Lg-Rec: R = 0.76; Sh-Rw vs Lg-Rw: R = 0.85) and cross sections (Sh-Rec vs Sh-Rw: R = 0.49; Lg-Rec vs Lg-Rw: R = 0.65). For A-DVHs, however, the parameters of Sh rectal A-DVHs hardly changed

  5. Radiation tolerance of the cervical spinal cord: incidence and dose-volume relationship of symptomatic and asymptomatic late effects following high dose irradiation of paraspinal tumors

    International Nuclear Information System (INIS)

    Liu, Mitchell C.C.; Munzenrider, John E.; Finkelstein, Dianne; Liebsch, Norbert; Adams, Judy; Hug, Eugen B.

    1997-01-01

    Purpose: Low grade chordomas and chondrosarcomas require high radiation doses for effective, lasting tumor control. Fractionated, 3-D planned, conformal proton radiation therapy has been used for lesions along the base of skull and spine to deliver high target doses, while respecting constraints of critical, normal tissues. In this study, we sought to determine the incidence of myelopathy after high dose radiotherapy to the cervical spine and investigated the influence of various treatment parameters, including dose-volume relationship. Methods and Materials: Between December 1980 and March 1996, 78 patients were treated at the Massachusetts General Hospital and Harvard Cyclotron Laboratory for primary or recurrent chordomas and chondrosarcomas of the cervical spine using combined proton and photon radiation therapy. In general, the tumor dose given was between 64.5 to 79.2 CGE (Cobalt Gray Equivalent). The guidelines for maximum permissible doses to spinal cord were: ≤ 64 CGE to the spinal cord surface and ≤ 53 CGE to the spinal cord center. Dose volume histograms of the spinal cord were analyzed to investigate a possible dose and volume relationship. Results: With a mean follow-up period of 46.6 months (range: 3 - 157 months), 4 of 78 patients (5.1%) developed high-grade (RTOG Grade 3 and 4) late toxicity: 3 patients (3.8%) experienced sensory deficits without motor deficits, none had any limitations of daily activities. One patient (1.2%) developed motor deficit with loss of motor function of one upper extremity. The only patient, who developed permanent motor damage had received additional prior radiation treatment and therefore received a cumulative spinal cord dose higher than the treatment guidelines. No patient treated within the guidelines experienced any motor impairment. Six patients (7.7%) experienced transient Lhermitt's syndrome and 1 patient (1.2%) developed asymptomatic radiographic MR findings only. Time to onset of symptoms of radiographic

  6. Parotid gland tumors: A comparison of postoperative radiotherapy techniques using three dimensional (3D) dose distributions and dose-volume histograms (DVHs)

    International Nuclear Information System (INIS)

    Yaparpalvi, Ravindra; Fontenla, Doracy P.; Tyerech, Sangeeta K.; Boselli, Lucia R.; Beitler, Jonathan J.

    1998-01-01

    Purpose: To compare different treatment techniques for unilateral treatment of parotid gland tumors. Methods and Materials: The CT-scans of a representative parotid patient were used. The field size was 9 x 11 cm, the separation was 15.5 cm, and the prescription depth was 4.5 cm. Using 3D dose distributions, tissue inhomogeneity corrections, scatter integration (for photons) and pencil beam (for electrons) algorithms and dose-volume histogram (DVH), nine treatment techniques were compared. [1] unilateral 6 MV photons [2] unilateral 12 MeV electrons [3] unilateral 16 MeV electrons [4] an ipsilateral wedge pair technique using 6 MV photons [5] a 3-field AP (wedged), PA (wedged) and lateral portal technique using 6 MV photons [6] a mixed beam technique using 6 MV photons and 12 MeV electrons (1:4 weighting) [7] a mixed beam technique using 6 MV photons and 16 MeV electrons (1:4 weighting) [8] a mixed beam technique using 18 MV photons and 20 MeV electrons (2:3 weighting) [9] a mixed beam technique using 18 MV photons and 20 MeV electrons (1:1 weighting). Results: Using dose-volume histograms to evaluate the dose to the contralateral parotid gland, the percentage of contralateral parotid volume receiving ≥ 30% of the prescribed dose was 100% for techniques [1], [8] and [9], and < 5% for techniques [2] through [7]. Evaluating the 'hottest' 5 cc of the ipsilateral mandible and temporal lobes, the hot spots were: 152% and 150% for technique [2], 132% and 130% for technique [6]. Comparing the exit doses, techniques [1], [8] and [9] contributed to ≥ 50% of the prescribed dose to the contralateral mandible and the temporal lobes. Only techniques [2] and [6] kept the highest point doses to both the brain stem and the spinal cord below 50% of the prescribed dose. Conclusion: The single photon lateral field [1] and the mixed electron-photon beams [8] and [9] are not recommended treatment techniques for unilateral parotid irradiation because of high doses delivered to the

  7. CT-guided intracavitary radiotherapy for cervical cancer: Comparison of conventional point A plan with clinical target volume-based three-dimensional plan using dose-volume parameters

    International Nuclear Information System (INIS)

    Shin, Kyung Hwan; Kim, Tae Hyun; Cho, Jung Keun; Kim, Joo-Young; Park, Sung Yong; Park, Sang-Yoon; Kim, Dae Yong; Chie, Eui Kyu; Pyo, Hong Ryull; Cho, Kwan Ho

    2006-01-01

    Purpose: To perform an intracavitary radiotherapy (ICR) plan comparison between the conventional point A plan (conventional plan) and computed tomography (CT)-guided clinical target volume-based plan (CTV plan) by analysis of the quantitative dose-volume parameters and irradiated volumes of organs at risk in patients with cervical cancer. Methods and Materials: Thirty plans for 192 Ir high-dose-rate ICR after 30-40-Gy external beam radiotherapy were investigated. CT images were acquired at the first ICR session with artifact-free applicators in place. The gross tumor volume, clinical target volume (CTV), point A, and International Commission on Radiation Units and Measurements Report 38 rectal and bladder points were defined on reconstructed CT images. A fractional 100% dose was prescribed to point A in the conventional plan and to the outermost point to cover all CTVs in the CTV plan. The reference volume receiving 100% of the prescribed dose (V ref ), and the dose-volume parameters of the coverage index, conformal index, and external volume index were calculated from the dose-volume histogram. The bladder, rectal point doses, and percentage of volumes receiving 50%, 80%, and 100% of the prescribed dose were also analyzed. Results: Conventional plans were performed, and patients were categorized on the basis of whether the 100% isodose line of point A prescription dose fully encompassed the CTV (Group 1, n = 20) or not (Group 2, n = 10). The mean gross tumor volume (11.6 cm 3 ) and CTV (24.9 cm 3 ) of Group 1 were smaller than the corresponding values (23.7 and 44.7 cm 3 , respectively) for Group 2 (p = 0.003). The mean V ref for all patients was 129.6 cm 3 for the conventional plan and 97.0 cm 3 for the CTV plan (p = 0.003). The mean V ref in Group 1 decreased markedly with the CTV plan (p < 0.001). For the conventional and CTV plans in all patients, the mean coverage index, conformal index, and external volume index were 0.98 and 1.0, 0.23 and 0.34, and 3.86 and

  8. Parotid gland tumors: a comparison of postoperative radiotherapy techniques using three dimensional (3-D) dose distributions and dose-volume histograms (DVH)

    International Nuclear Information System (INIS)

    Yaparpalvi, R.; Tyerech, S.K.; Boselli, L.R.; Fontenla, D.P.; Beitler, J.J.; Vikram, B.

    1996-01-01

    Purpose/Objective: To compare different treatment techniques for unilateral treatment of parotid gland tumors. Materials and Methods: Twenty patients previously treated postoperatively for parotid gland tumors were retrospectively reviewed. Average field size was 9 x 11 cm, average separation was 15.5 cm, and the average prescription depth was 4.5 cm. Using 3-D dose distributions, tissue inhomogeneity corrections, scatter integration (for photons) and pencil beam (for electrons) algorithms and DVH, nine treatment techniques were compared using a representative patient. The treatment techniques investigated were: [1] unilateral 6 MV photons. [2] unilateral 12 MeV electrons. [3] unilateral 16 MeV electrons. [4] a ipsilateral wedge pair technique using 6 MV photons and a 45-degree wedge. [5] a 3-field AP (wedged), PA (wedged) and lateral portal technique using 6 MV photons. [6] a mixed beam technique using 6 MV photons and 12 MeV electrons (1:4 weighting). [7] a mixed beam technique using 6 MV photons and 16 MeV electrons (1:4 weighting). [8] a mixed beam technique using 18 MV photons and 20 MeV electrons (2:3 weighting). [9] a mixed beam technique using 18 MV photons and 20 MeV electrons (1:1 weighting). Results: Using dose-volume histograms to evaluate the dose to the contralateral parotid gland, the percentage of contralateral parotid volume receiving ≥30% of the prescribed dose was 100% for techniques [1], [8] and [9], and <5% for techniques [2] through [7]. Evaluating the 'hottest' 5 cc of the ipsilateral mandible and temporal lobes, the hot spots were: 152% and 150% for technique [2], 132% and 130% for technique [6]. Comparing the exit doses, techniques [1] and [8] contributed to ≥50% of the prescribed dose to the contralateral mandible and the temporal lobes. Only techniques [2] and [6] kept the highest point doses to both the brain stem and the spinal cord below 50% of the prescribed dose. Conclusion: The single photon lateral field [1] and the mixed

  9. A dose-volume comparison of prostate cancer (PC) radiotherapy (RT) techniques for penile-structures (PNS) - a neglected critical organ in PC RT

    International Nuclear Information System (INIS)

    Dabrowski, Jolanta; Myrianthopoulos, Leon; Nguyen, Ai; Chen, George; Vijayakumar, Srinivasan

    1996-01-01

    Purpose/Objective: Three-dimensional conformal RT(3DCRT) is revolutionizing the use of RT in PC. Rectum and bladder, and in some studies femoral heads are included as critical structures (CS) in comparing rival plans in 3DCRT. Although RT-induced impotence is a major complication of conventional RT, with 30-50% incidence, to date no study has included PNS as a CS. This study is an attempt to remedy this deficiency in the 3DCRT planning in PC. Materials and Methods: After immobilization with Aquaplast, computed-tomography (CT) scans were obtained in supine treatment position from top of lumbar-3 vertebra to lesser-trochanter of the femora with 5-8mm slice-thicknesses; IV contrast was used in all patients. Prostate, seminal vesicles (GTV), and CSs were outlined, including PNS. Corpora cavernosa and bulbous spongiosum together were identified as PNS. Appropriate margins for CTV and PTV were used; total margin to the block from GTV was 2cm. Tumor-minimum doses were prescribed to the 100% isodose line. Dose-volume histograms (DVHs) were obtained to compare three different techniques: 1. Conventional 4 field box technique (4FC) with equal weighting; 2. Six field (2 laterals and 4 obliques [45 degrees from midline] (6FO), with 50% dose delivery from the laterals; and 3. Four equally weighted, non-axial fields [2 laterals and 2 inferior anterior obliques at 45 degree couch and gantry rotations] (4FN). Results: A total of 12 patients are included in the study. The mean and range of percentage volume of PNS receiving more than 30, 60, and 90% of the prescribed dose are shown in the table below: Box plots, such as the example shown above, were used to compare techniques overall. The 6-field coplanar technique treated the least PNS volume beyond a given dose, followed by 4FC and 4FN techniques. The order of least to maximum percent of PNS treated in most individual patients also followed the same trend. In the majority, 6FO and 4FN delivered relatively comparable doses to

  10. Measuring side effects after radiotherapy for pharynx cancer

    DEFF Research Database (Denmark)

    Jensen, Kenneth

    2007-01-01

    Data on side effects after radiotherapy is needed to establish the benefits and drawbacks of new treatments, but side effects are not quantified as easily as survival or local control. Side effects may be quantified using physical measures. Unfortunately, only few endpoints exist where a physical...... measure is obtainable, and the case of a patient-relevant measure is even rarer. Radiotherapy is often followed by complex symptoms not easily quantifiable by the observer. Quantitative patient reported side effects can be retrieved using validated questionnaires, but this kind of data is often difficult...... to interpret and the correlation with clinically observable or measurable changes not straightforward. The exploitation of the possibilities of highly conformal radiotherapy and multimodality treatment depends on a better understanding of the correlation between dose, volume, modifying factors, and side...

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  12. The value of regional nodal radiotherapy (dose/volume) in the treatment of unresectable non-small cell lung cancer: an RTOG analysis

    International Nuclear Information System (INIS)

    Emami, Bahman; Scott, Charles; Byhardt, Roger; Graham, Mary V.; Andras, E. James; John, Madhu; Herskovic, Arnold; Urtasun, Raul C.; Asbell, Sucha O.; Perez, Carlos A.; Cox, James

    1996-01-01

    PURPOSE/OBJECTIVE: To evaluate whether or not the traditional practice of including all thoracic regional nodal areas in the radiotherapy volume in the treatment of unresectable lung cancer is of any therapeutic benefit. MATERIALS AND METHODS: A total of 1,705 patients from four large RTOG trials (78-11, 79-17, 83-11, 84-07) were analyzed for this purpose. Each of these trials had data on dose delivered to the nodal regions and assessment of nodal borders. The nodes were separated into mediastinal, contralateral hilar, ipsilateral hilar, and supraclavicular. Each node site was assessed for progression, defined as in-field or out-of-field, at the node site. In patients with adequate nodal field borders, the results were also analyzed according to the dose delivered. RESULTS: The majority (74%) of patients were between the age of 55 to 75. Forty-six percent of patients had KPS of 60 to 80 and 52% KPS of 90 to 100. Sixty percent of patients had a weight loss of less than 5%, and 40% had a weight loss of over 5% six months prior to diagnosis. Major variations from protocol in defining field borders (unacceptable field borders) were lowest for ipsilateral hilum ((42(727))) and the highest for mediastinal borders ((158(743))). Three groups had statistically significant differences in outcome (progression) between the per protocol and the unacceptable per protocol: ipsilateral hilar nodes (field borders), 14% versus 26% (p = 0.03); dose to mediastinal nodes in CALGB eligible patients, 9% versus 19% (p = 0.02); and ipsilateral hilar nodes (field borders) for high-dose patients assigned to greater than or equal to 69.6 Gy, 14% versus 31% (p = 0.007). CONCLUSION: These data suggest that inclusion of the ipsilateral hilar and mediastinal nodes affect outcome in unresectable non-small cell lung cancer. Exclusion of the other thoracic lymph node regions did not affect outcome in this study. These findings have important implications for combined modality therapy and three

  13. High-dose (70-78 GY) conformal radiotherapy for prostate cancer; the relation between observed late bladder and rectum complications and parameters derived from the dose volume histograms

    International Nuclear Information System (INIS)

    Lebesque, J.V.; Bruce, A.; Boersma, L.J.; Velde, A. te

    1996-01-01

    Purpose: To determine the incidence of late gastrointestinal (GI) and genitourinary (GU) complications after conformal radiotherapy for prostate cancer, and to investigate the relation between these observed incidences and parameters derived from the Dose Volume Histograms (DVHs) of rectum and bladder wall. Patients and Methods: Hundred and thirty patients with T 2-4 G 1-3 N 0 M 0 prostate cancer were treated with conformal radiotherapy with the simultaneous boost technique in a dose-escalating protocol; 78 patients received a total dose of 70 Gy, 11 patients 74 - 76 Gy and 41 patients 78 Gy, each with a dose of 2 Gy per fraction. DVHs of the rectal wall were used to calculate NTCPs according to the model of Kutcher et al. with the estimated parameter values (n = 0.12, m = 0.15, TD 50 = 80 Gy) according to Burman et al. The median follow-up was 17 months (range 6 - 72 months). The crude and actuarial incidence of late (> 6 months) GI and GU complications were determined using the RTOG/EORTC morbidity scoring system (Grade I to IV). Results: Neither for late GI nor for GU complaints, a grade IV complication was observed. GU complaints occurred in 90 patients (69%): 54 patients (42%) only experienced grade I toxicity, 26 patients (20%) had grade II toxicity, and 10 patients (8%) had grade III complications, of which 8 patients (6%) developed a urethral (7 pts) or ureteric stenosis (1 pt). The actuarial incidence of grade III GU complications was 10% at 2 years. Since bladder wall DVHs are unreliable and most grade III complications were not related to the bladder, the grade II and/or III complications were analyzed in terms of the total prescribed dose only, but no correlation could be demonstrated. GI complications occurred in 71 patients (55%): 59 patients (45%) developed a grade I complication, 11 a grade II complication and only 1 patient required laser treatment twice and blood transfusion because of rectal bleeding (grade III). The actuarial incidence of GI

  14. Beyond mean pharyngeal constrictor dose for beam path toxicity in non-target swallowing muscles: dose-volume correlates of chronic radiation-associated dysphagia (RAD) after oropharyngeal intensity modulated radiotherapy

    Science.gov (United States)

    2016-01-01

    Purpose/Objective(s) We sought to identify swallowing muscle dose-response thresholds associated with chronic radiation-associated dysphagia (RAD) after IMRT for oropharyngeal cancer. Materials/Methods T1-4 N0-3 M0 oropharyngeal cancer patients who received definitive IMRT and systemic therapy were examined. Chronic RAD was coded as any of the following ≥ 12 months post-IMRT: videofluoroscopy/endoscopy detected aspiration or stricture, gastrostomy tube and/or aspiration pneumonia. DICOM-RT plan data were autosegmented using a custom region-of-interest (ROI) library and included inferior, middle and superior constrictors (IPC, MPC, and SPC), medial and lateral pterygoids (MPM, LPM), anterior and posterior digastrics (ADM, PDM), intrinsic tongue muscles (ITM), mylo/geniohyoid complex (MHM), genioglossus (GGM), ), masseter (MM), Buccinator (BM), palatoglossus (PGM), and cricopharyngeus (CPM), with ROI dose-volume histograms (DVHs) calculated. Recursive partitioning analysis (RPA) was used to identify dose-volume effects associated with chronic-RAD, for use in a multivariate (MV) model. Results Of 300 patients, 34 (11%) had chronic-RAD. RPA showed DVH-derived MHM V69 (i.e. the volume receiving ≥69Gy), GGM V35, ADM V60, MPC V49, and SPC V70 were associated with chronic-RAD. A model including age in addition to MHM V69 as continuous variables was optimal among tested MV models (AUC 0.835). Conclusion In addition to SPCs, dose to MHM should be monitored and constrained, especially in older patients (>62-years), when feasible. PMID:26897515

  15. Beyond mean pharyngeal constrictor dose for beam path toxicity in non-target swallowing muscles: Dose-volume correlates of chronic radiation-associated dysphagia (RAD) after oropharyngeal intensity modulated radiotherapy.

    Science.gov (United States)

    2016-02-01

    We sought to identify swallowing muscle dose-response thresholds associated with chronic radiation-associated dysphagia (RAD) after IMRT for oropharyngeal cancer. T1-4 N0-3 M0 oropharyngeal cancer patients who received definitive IMRT and systemic therapy were examined. Chronic RAD was coded as any of the following ⩾12months post-IMRT: videofluoroscopy/endoscopy detected aspiration or stricture, gastrostomy tube and/or aspiration pneumonia. DICOM-RT plan data were autosegmented using a custom region-of-interest (ROI) library and included inferior, middle and superior constrictors (IPC, MPC, and SPC), medial and lateral pterygoids (MPM, LPM), anterior and posterior digastrics (ADM, PDM), intrinsic tongue muscles (ITM), mylo/geniohyoid complex (MHM), genioglossus (GGM), masseter (MM), buccinator (BM), palatoglossus (PGM), and cricopharyngeus (CPM), with ROI dose-volume histograms (DVHs) calculated. Recursive partitioning analysis (RPA) was used to identify dose-volume effects associated with chronic-RAD, for use in a multivariate (MV) model. Of 300 patients, 34 (11%) had chronic-RAD. RPA showed DVH-derived MHM V69 (i.e. the volume receiving⩾69Gy), GGM V35, ADM V60, MPC V49, and SPC V70 were associated with chronic-RAD. A model including age in addition to MHM V69 as continuous variables was optimal among tested MV models (AUC 0.835). In addition to SPCs, dose to MHM should be monitored and constrained, especially in older patients (>62-years), when feasible. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Bystander effects and radiotherapy.

    Science.gov (United States)

    Marín, Alicia; Martín, Margarita; Liñán, Olga; Alvarenga, Felipe; López, Mario; Fernández, Laura; Büchser, David; Cerezo, Laura

    2015-01-01

    Radiation-induced bystander effects are defined as biological effects expressed after irradiation by cells whose nuclei have not been directly irradiated. These effects include DNA damage, chromosomal instability, mutation, and apoptosis. There is considerable evidence that ionizing radiation affects cells located near the site of irradiation, which respond individually and collectively as part of a large interconnected web. These bystander signals can alter the dynamic equilibrium between proliferation, apoptosis, quiescence or differentiation. The aim of this review is to examine the most important biological effects of this phenomenon with regard to areas of major interest in radiotherapy. Such aspects include radiation-induced bystander effects during the cell cycle under hypoxic conditions when administering fractionated modalities or combined radio-chemotherapy. Other relevant aspects include individual variation and genetics in toxicity of bystander factors and normal tissue collateral damage. In advanced radiotherapy techniques, such as intensity-modulated radiation therapy (IMRT), the high degree of dose conformity to the target volume reduces the dose and, therefore, the risk of complications, to normal tissues. However, significant doses can accumulate out-of-field due to photon scattering and this may impact cellular response in these regions. Protons may offer a solution to reduce out-of-field doses. The bystander effect has numerous associated phenomena, including adaptive response, genomic instability, and abscopal effects. Also, the bystander effect can influence radiation protection and oxidative stress. It is essential that we understand the mechanisms underlying the bystander effect in order to more accurately assess radiation risk and to evaluate protocols for cancer radiotherapy.

  17. The Effect of Dose-Volume Parameters and Interfraction Interval on Cosmetic Outcome and Toxicity After 3-Dimensional Conformal Accelerated Partial Breast Irradiation

    International Nuclear Information System (INIS)

    Leonard, Kara Lynne; Hepel, Jaroslaw T.; Hiatt, Jessica R.; Dipetrillo, Thomas A.; Price, Lori Lyn; Wazer, David E.

    2013-01-01

    Purpose: To evaluate dose-volume parameters and the interfraction interval (IFI) as they relate to cosmetic outcome and normal tissue effects of 3-dimensional conformal radiation therapy (3D-CRT) for accelerated partial breast irradiation (APBI). Methods and Materials: Eighty patients were treated by the use of 3D-CRT to deliver APBI at our institutions from 2003-2010 in strict accordance with the specified dose-volume constraints outlined in the National Surgical Adjuvant Breast and Bowel Project B39/Radiation Therapy Oncology Group 0413 (NSABP-B39/RTOG 0413) protocol. The prescribed dose was 38.5 Gy in 10 fractions delivered twice daily. Patients underwent follow-up with assessment for recurrence, late toxicity, and overall cosmetic outcome. Tests for association between toxicity endpoints and dosimetric parameters were performed with the chi-square test. Univariate logistic regression was used to evaluate the association of interfraction interval (IFI) with these outcomes. Results: At a median follow-up time of 32 months, grade 2-4 and grade 3-4 subcutaneous fibrosis occurred in 31% and 7.5% of patients, respectively. Subcutaneous fibrosis improved in 5 patients (6%) with extended follow-up. Fat necrosis developed in 11% of women, and cosmetic outcome was fair/poor in 19%. The relative volume of breast tissue receiving 5%, 20%, 50%, 80%, and 100% (V5-V100) of the prescribed dose was associated with risk of subcutaneous fibrosis, and the volume receiving 50%, 80%, and 100% (V50-V100) was associated with fair/poor cosmesis. The mean IFI was 6.9 hours, and the minimum IFI was 6.2 hours. The mean and minimum IFI values were not significantly associated with late toxicity. Conclusions: The incidence of moderate to severe late toxicity, particularly subcutaneous fibrosis and fat necrosis and resulting fair/poor cosmesis, remains high with continued follow-up. These toxicity endpoints are associated with several dose-volume parameters. Minimum and mean IFI values were

  18. Comparison of different contouring definitions of the rectum as organ at risk (OAR) and dose-volume parameters predicting rectal inflammation in radiotherapy of prostate cancer: which definition to use?

    Science.gov (United States)

    Nitsche, Mirko; Brannath, Werner; Brückner, Matthias; Wagner, Dirk; Kaltenborn, Alexander; Temme, Nils; Hermann, Robert M

    2017-02-01

    The objective of this retrospective planning study was to find a contouring definition for the rectum as an organ at risk (OAR) in curative three-dimensional external beam radiotherapy (EBRT) for prostate cancer (PCa) with a predictive correlation between the dose-volume histogram (DVH) and rectal toxicity. In a pre-study, the planning CT scans of 23 patients with PCa receiving definitive EBRT were analyzed. The rectum was contoured according to 13 different definitions, and the dose distribution was correlated with the respective rectal volumes by generating DVH curves. Three definitions were identified to represent the most distinct differences in the shapes of the DVH curves: one anatomical definition recommended by the Radiation Therapy Oncology Group (RTOG) and two functional definitions based on the target volume. In the main study, the correlation between different relative DVH parameters derived from these three contouring definitions and the occurrence of rectal toxicity during and after EBRT was studied in two consecutive collectives. The first cohort consisted of 97 patients receiving primary curative EBRT and the second cohort consisted of 66 patients treated for biochemical recurrence after prostatectomy. Rectal toxicity was investigated by clinical investigation and scored according to the Common Terminology Criteria for Adverse Events. Candidate parameters were the volume of the rectum, mean dose, maximal dose, volume receiving at least 60 Gy (V 60 ), area under the DVH curve up to 25 Gy and area under the DVH curve up to 75 Gy in dependence of each chosen rectum definition. Multivariable logistic regression considered other clinical factors such as pelvine lymphatics vs local target volume, diabetes, prior rectal surgery, anticoagulation or haemorrhoids too. In Cohort 1 (primary EBRT), the mean rectal volumes for definitions "RTOG", planning target volume "(PTV)-based" and "PTV-linked" were 100 cm 3 [standard deviation (SD) 43 cm 3 ], 60

  19. SU-F-T-348: The Impact of Model Library Population On RapidPlan Based Dose-Volume Histograms (DVHs) Prediction for Rectal Cancer Patients Treated with Volumetric-Modulated Radiotherapy (VMAT)

    International Nuclear Information System (INIS)

    Li, K; Zhou, L; Chen, Z; Peng, J; Hu, W

    2016-01-01

    Purpose: RapidPlan uses a library consisting of expert plans from different patients to create a model that can predict achievable dose-volume histograms (DVHs) for new patients. The goal of this study is to investigate the impacts of model library population (plan numbers) on the DVH prediction for rectal cancer patients treated with volumetric-modulated radiotherapy (VMAT) Methods: Ninety clinically accepted rectal cancer patients’ VMAT plans were selected to establish 3 models, named as Model30, Model60 and Model90, with 30,60, and 90 plans in the model training. All plans had sufficient target coverage and bladder and femora sparings. Additional 10 patients were enrolled to test the DVH prediction differences with these 3 models. The predicted DVHs from these 3 models were compared and analyzed. Results: Predicted V40 (Vx, percent of volume that received x Gy for the organs at risk) and Dmean (mean dose, cGy) of the bladder were 39.84±13.38 and 2029.4±141.6 for the Model30,37.52±16.00 and 2012.5±152.2 for the Model60, and 36.33±18.35 and 2066.5±174.3 for the Model90. Predicted V30 and Dmean of the left femur were 23.33±9.96 and 1443.3±114.5 for the Model30, 21.83±5.75 and 1436.6±61.9 for the Model60, and 20.31±4.6 and 1415.0±52.4 for the Model90.There were no significant differences among the 3 models for the bladder and left femur predictions. Predicted V40 and Dmean of the right femur were 19.86±10.00 and 1403.6±115.6 (Model30),18.97±6.19 and 1401.9±68.78 (Model60), and 21.08±7.82 and 1424.0±85.3 (Model90). Although a slight lower DVH prediction of the right femur was found on the Model60, the mean differences for V30 and mean dose were less than 2% and 1%, respectively. Conclusion: There were no significant differences among Model30, Model60 and Model90 for predicting DVHs on rectal patients treated with VMAT. The impact of plan numbers for model library might be limited for cancers with similar target shape.

  20. SU-F-T-348: The Impact of Model Library Population On RapidPlan Based Dose-Volume Histograms (DVHs) Prediction for Rectal Cancer Patients Treated with Volumetric-Modulated Radiotherapy (VMAT)

    Energy Technology Data Exchange (ETDEWEB)

    Li, K; Zhou, L; Chen, Z; Peng, J; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: RapidPlan uses a library consisting of expert plans from different patients to create a model that can predict achievable dose-volume histograms (DVHs) for new patients. The goal of this study is to investigate the impacts of model library population (plan numbers) on the DVH prediction for rectal cancer patients treated with volumetric-modulated radiotherapy (VMAT) Methods: Ninety clinically accepted rectal cancer patients’ VMAT plans were selected to establish 3 models, named as Model30, Model60 and Model90, with 30,60, and 90 plans in the model training. All plans had sufficient target coverage and bladder and femora sparings. Additional 10 patients were enrolled to test the DVH prediction differences with these 3 models. The predicted DVHs from these 3 models were compared and analyzed. Results: Predicted V40 (Vx, percent of volume that received x Gy for the organs at risk) and Dmean (mean dose, cGy) of the bladder were 39.84±13.38 and 2029.4±141.6 for the Model30,37.52±16.00 and 2012.5±152.2 for the Model60, and 36.33±18.35 and 2066.5±174.3 for the Model90. Predicted V30 and Dmean of the left femur were 23.33±9.96 and 1443.3±114.5 for the Model30, 21.83±5.75 and 1436.6±61.9 for the Model60, and 20.31±4.6 and 1415.0±52.4 for the Model90.There were no significant differences among the 3 models for the bladder and left femur predictions. Predicted V40 and Dmean of the right femur were 19.86±10.00 and 1403.6±115.6 (Model30),18.97±6.19 and 1401.9±68.78 (Model60), and 21.08±7.82 and 1424.0±85.3 (Model90). Although a slight lower DVH prediction of the right femur was found on the Model60, the mean differences for V30 and mean dose were less than 2% and 1%, respectively. Conclusion: There were no significant differences among Model30, Model60 and Model90 for predicting DVHs on rectal patients treated with VMAT. The impact of plan numbers for model library might be limited for cancers with similar target shape.

  1. Effects of first-dose volume and exercise on the efficacy and tolerability of bowel preparations for colonoscopy in Chinese people

    Directory of Open Access Journals (Sweden)

    Qin Y

    2016-04-01

    Full Text Available Ying Qin, Wei Liu, Songbai Lin, Xiangfeng Li International Medical Services, Peking Union Medical College Hospital, Beijing, People’s Republic of China Aim: This study was designed to compare the efficacy and tolerability of bowel preparations with and without the higher first-dose volume of polyethylene glycol (PEG solution or exercise after drinking PEG solution in Chinese people. Methods: A total of 330 participants who had a colonoscopy done in Peking Union Medical College Hospital were randomly and evenly assigned to three groups. Participants in Group A ingested 1 L PEG solution and then ingested 2 L PEG solution at a rate of 250 mL every 15 minutes. Participants in Group B ingested 3 L PEG solution at a rate of 250 mL every 15 minutes and then exercised more than 10 minutes after ingesting each liter of PEG solution. Participants in Group C ingested 3 L PEG solution at a rate of 250 mL every 15 minutes. Experienced gastrointestinal endoscopists rated the efficacy of bowel preparations based on the Boston Bowel Preparation Scale score. A questionnaire regarding participants’ symptoms associated with bowel preparations was administered to evaluate participants’ tolerability. Results: The three groups had insignificant difference in the percentages of participants’ symptoms including dizziness, nausea, stomach ache, bloating, and asthenia. However, the percentages of participants having hunger sensation, sleep disturbance, and anal discomfort were significantly higher in groups with the higher first-dose volume of PEG solution or exercise after drinking PEG solution than without them. The three groups had insignificant difference in the Boston Bowel Preparation Scale score. Conclusion: Whether to add the higher first-dose volume of PEG solution and exercise after drinking PEG solution or not, all participants achieved a similar quality of bowel preparations. Bowel preparations without the additional first-dose volume of PEG

  2. Reliability of dose volume constraint inference from clinical data

    DEFF Research Database (Denmark)

    Lutz, C M; Møller, D S; Hoffmann, L

    2017-01-01

    Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background...... was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an 'ideal' cohort was generated where the most predictive model was equal to the postulated model. A bootstrap...

  3. Rectal Bleeding After High-Dose-Rate Brachytherapy Combined With Hypofractionated External-Beam Radiotherapy for Localized Prostate Cancer: The Relationship Between Dose-Volume Histogram Parameters and the Occurrence Rate

    International Nuclear Information System (INIS)

    Okamoto, Masahiko; Ishikawa, Hitoshi; Ebara, Takeshi; Kato, Hiroyuki; Tamaki, Tomoaki; Akimoto, Tetsuo; Ito, Kazuto; Miyakubo, Mai; Yamamoto, Takumi; Suzuki, Kazuhiro; Takahashi, Takeo; Nakano, Takashi

    2012-01-01

    Purpose: To determine the predictive risk factors for Grade 2 or worse rectal bleeding after high-dose-rate brachytherapy (HDR-BT) combined with hypofractionated external-beam radiotherapy (EBRT) for prostate cancer using dose–volume histogram analysis. Methods and Materials: The records of 216 patients treated with HDR-BT combined with EBRT were analyzed. The treatment protocols for HDR-BT were 5 Gy × five times in 3 days or 7 Gy × three, 10.5 Gy × two, or 9 Gy × two in 2 days. The EBRT doses ranged from 45 to 51 Gy with a fractional dose of 3 Gy. Results: In 20 patients Grade 2 or worse rectal bleeding developed, and the cumulative incidence rate was 9% at 5 years. By converting the HDR-BT and EBRT radiation doses into biologic effective doses (BED), the BED 3 at rectal volumes of 5% and 10% in the patients who experienced bleeding were significantly higher than those in the remaining 196 patients. Univariate analysis showed that a higher rectal BED 3–5% and the use of fewer needles in brachytherapy were correlated with the incidence of bleeding, but BED 3–5% was found to be the only significant factor on multivariate analysis. Conclusions: The radiation dose delivered to small rectal lesions as 5% is important for predicting Grade 2 or worse rectal bleeding after HDR-BT combined with EBRT for prostate cancer.

  4. Isobio software: biological dose distribution and biological dose volume histogram from physical dose conversion using linear-quadratic-linear model.

    Science.gov (United States)

    Jaikuna, Tanwiwat; Khadsiri, Phatchareewan; Chawapun, Nisa; Saekho, Suwit; Tharavichitkul, Ekkasit

    2017-02-01

    To develop an in-house software program that is able to calculate and generate the biological dose distribution and biological dose volume histogram by physical dose conversion using the linear-quadratic-linear (LQL) model. The Isobio software was developed using MATLAB version 2014b to calculate and generate the biological dose distribution and biological dose volume histograms. The physical dose from each voxel in treatment planning was extracted through Computational Environment for Radiotherapy Research (CERR), and the accuracy was verified by the differentiation between the dose volume histogram from CERR and the treatment planning system. An equivalent dose in 2 Gy fraction (EQD 2 ) was calculated using biological effective dose (BED) based on the LQL model. The software calculation and the manual calculation were compared for EQD 2 verification with pair t -test statistical analysis using IBM SPSS Statistics version 22 (64-bit). Two and three-dimensional biological dose distribution and biological dose volume histogram were displayed correctly by the Isobio software. Different physical doses were found between CERR and treatment planning system (TPS) in Oncentra, with 3.33% in high-risk clinical target volume (HR-CTV) determined by D 90% , 0.56% in the bladder, 1.74% in the rectum when determined by D 2cc , and less than 1% in Pinnacle. The difference in the EQD 2 between the software calculation and the manual calculation was not significantly different with 0.00% at p -values 0.820, 0.095, and 0.593 for external beam radiation therapy (EBRT) and 0.240, 0.320, and 0.849 for brachytherapy (BT) in HR-CTV, bladder, and rectum, respectively. The Isobio software is a feasible tool to generate the biological dose distribution and biological dose volume histogram for treatment plan evaluation in both EBRT and BT.

  5. Incidence of radiation pneumonitis after thoracic irradiation: Dose-volume correlates

    International Nuclear Information System (INIS)

    Schallenkamp, John M.; Miller, Robert C.; Brinkmann, Debra H.; Foote, Tyler; Garces, Yolanda I.

    2007-01-01

    Purpose: To define clinical and dosimetric parameters correlated with the risk of clinically relevant radiation pneumonitis (RP) after thoracic radiotherapy. Methods and Materials: Records of consecutive patients treated with definitive thoracic radiotherapy were retrospectively reviewed for the incidence of RP of Grade 2 or greater by the Common Toxicity Criteria. Dose-volume histograms using total lung volume (TL) and TL minus gross tumor volume (TL-G) were created with and without heterogeneity corrections. Mean lung dose (MLD), effective lung volume (V eff ), and percentage of TL or TL-G receiving greater than or equal to 10, 13, 15, 20, and 30 Gy (V10-V30, respectively) were analyzed by logistic regression. Receiver operating characteristic (ROC) curves were generated to estimate RP predictive values. Results: Twelve cases of RP were identified in 92 eligible patients. Mean lung dose, V10, V13, V15, V20, and V eff were significantly correlated to RP. Combinations of MLD, V eff , V20, and V30 lost significance using TL-G and heterogeneity corrections. Receiver operating characteristic analysis determined V10 and V13 as the best predictors of RP risk, with a decrease in predictive value above those volumes. Conclusions: Intrathoracic radiotherapy should be planned with caution when using radiotherapy techniques delivering doses of 10 to 15 Gy to large lung volumes

  6. Influence of dosing volume on the neurotoxicity of bifenthrin.

    Science.gov (United States)

    Wolansky, M J; McDaniel, K L; Moser, V C; Crofton, K M

    2007-01-01

    Pyrethroids are pesticides with high insecticidal activity and relatively low potency in mammals. The influence of dosing volume on the neurobehavioral syndrome following oral acute exposure to the Type-I pyrethroid insecticide bifenthrin in corn oil was evaluated in adult male Long Evans rats. We tested bifenthrin effects at 1 and 5 ml/kg, two commonly used dose volumes in toxicological studies. Two testing times (4 and 7 h) were used in motor activity and functional observational battery (FOB) assessments. Four to eight doses were examined at either dosing condition (up to 20 or 26 mg/kg, at 1 and 5 ml/kg, respectively). Acute oral bifenthrin exposure produced toxic signs typical of Type I pyrethroids, with dose-related increases in fine tremor, decreased motor activity and grip strength, and increased pawing, head shaking, click response, and body temperature. Bifenthrin effects on motor activity and pyrethroid-specific clinical signs were approximately 2-fold more potent at 1 ml/kg than 5 ml/kg. This difference was clearly evident at 4 h and slightly attenuated at 7 h post-dosing. Benchmark dose (BMD) modeling estimated similar 2-fold potency differences in motor activity and pyrethroid-specific FOB data. These findings demonstrate that dose volume, in studies using corn oil as the vehicle influences bifenthrin potency. Further, these data suggest that inconsistent estimates of pyrethroid potency between laboratories are at least partially due to differences in dosing volume.

  7. SU-F-J-217: Accurate Dose Volume Parameters Calculation for Revealing Rectum Dose-Toxicity Effect Using Deformable Registration in Cervical Cancer Brachytherapy: A Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Zhen, X; Chen, H; Liao, Y; Zhou, L [Southern Medical University, Guangzhou, Guangdong (China); Hrycushko, B; Albuquerque, K; Gu, X [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: To study the feasibility of employing deformable registration methods for accurate rectum dose volume parameters calculation and their potentials in revealing rectum dose-toxicity between complication and non-complication cervical cancer patients with brachytherapy treatment. Method and Materials: Data from 60 patients treated with BT including planning images, treatment plans, and follow-up clinical exam were retrospectively collected. Among them, 12 patients complained about hematochezia were further examined with colonoscopy and scored as Grade 1–3 complication (CP). Meanwhile, another 12 non-complication (NCP) patients were selected as a reference group. To seek for potential gains in rectum toxicity prediction when fractional anatomical deformations are account for, the rectum dose volume parameters D0.1/1/2cc of the selected patients were retrospectively computed by three different approaches: the simple “worstcase scenario” (WS) addition method, an intensity-based deformable image registration (DIR) algorithm-Demons, and a more accurate, recent developed local topology preserved non-rigid point matching algorithm (TOP). Statistical significance of the differences between rectum doses of the CP group and the NCP group were tested by a two-tailed t-test and results were considered to be statistically significant if p < 0.05. Results: For the D0.1cc, no statistical differences are found between the CP and NCP group in all three methods. For the D1cc, dose difference is not detected by the WS method, however, statistical differences between the two groups are observed by both Demons and TOP, and more evident in TOP. For the D2cc, the CP and NCP cases are statistically significance of the difference for all three methods but more pronounced with TOP. Conclusion: In this study, we calculated the rectum D0.1/1/2cc by simple WS addition and two DIR methods and seek for gains in rectum toxicity prediction. The results favor the claim that accurate dose

  8. Image-guided radiotherapy for effective radiotherapy delivery

    CERN Document Server

    Karlsson, Ulf Lennart

    2016-01-01

    Image-guided radiotherapy (IGRT) is a new radiotherapy technology that combines the rapid dose fall off associated with intensity-modulated radiotherapy (IMRT) and daily tumor imaging allowing for high precision tumor dose delivery and effective sparing of surrounding normal organs. The new radiation technology requires close collaboration between radiologists, nuclear medicine specialists, and radiation oncologists to avoid marginal miss. Modern diagnostic imaging such as positron emission tomography (PET) scans, positron emission tomography with Computed Tomograpgy (PET-CT), and magnetic resonance imaging (MRI) allows the radiation oncologist to target the positive tumor with high accuracy. As the tumor is well visualized during radiation treatment, the margins required to avoid geographic miss can be safely reduced , thus sparing the normal organs from excessive radiation. When the tumor is located close to critical radiosensitive structures such as the spinal cord, IGRT can deliver a high dose of radiatio...

  9. Radiotherapy

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kulikov, V.A.; Mardynskij, Yu.S.

    1984-01-01

    The technique for roentgenotopometric and medicamentous preparation of patients for radiotherapy has been reported in detail. The features of planning and performing of remote, intracavitary and combined therapy in urinary bladder cancer are considered. The more effective methods of radiotherapy have been proposed taking into account own experience as well as literature data. The comparative evaluation of treatment results and prognosis are given. Radiation pathomorphism of tumors and tissues of urinary bladder is considered in detail. The problems of diagnosis, prophylaxis and treatment of complications following radiodiagnosis and radiotherapy in patients with urinary bladder cancer are illustrated widely

  10. Genitourinary Toxicity After High-Dose-Rate (HDR) Brachytherapy Combined With Hypofractionated External Beam Radiotherapy for Localized Prostate Cancer: An Analysis to Determine the Correlation Between Dose-Volume Histogram Parameters in HDR Brachytherapy and Severity of Toxicity

    International Nuclear Information System (INIS)

    Ishiyama, Hiromichi; Kitano, Masashi; Satoh, Takefumi; Kotani, Shouko; Uemae, Mineko; Matsumoto, Kazumasa; Okusa, Hiroshi; Tabata, Ken-ichi; Baba, Shiro; Hayakawa, Kazushige

    2009-01-01

    Purpose: To evaluate the severity of genitourinary (GU) toxicity in high-dose-rate (HDR) brachytherapy combined with hypofractionated external beam radiotherapy (EBRT) for prostate cancer and to explore factors that might affect the severity of GU toxicity. Methods and Materials: A total of 100 Japanese men with prostate cancer underwent 192 Ir HDR brachytherapy combined with hypofractionated EBRT. Mean (SD) dose to 90% of the planning target volume was 6.3 (0.7) Gy per fraction of HDR. After 5 fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administrated. The urethral volume receiving 1-15 Gy per fraction in HDR brachytherapy (V1-V15) and the dose to at least 5-100% of urethral volume in HDR brachytherapy (D5-D100) were compared between patients with Grade 3 toxicity and those with Grade 0-2 toxicity. Prostate volume, patient age, and International Prostate Symptom Score were also compared between the two groups. Results: Of the 100 patients, 6 displayed Grade 3 acute GU toxicity, and 12 displayed Grade 3 late GU toxicity. Regarding acute GU toxicity, values of V1, V2, V3, and V4 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Regarding late GU toxicity, values of D70, D80, V12, and V13 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Conclusions: The severity of GU toxicity in HDR brachytherapy combined with hypofractionated EBRT for prostate cancer was relatively high. The volume of prostatic urethra was associated with grade of acute GU toxicity, and urethral dose was associated with grade of late GU toxicity.

  11. Effect of beam arrangement on oral cavity dose in external beam radiotherapy of nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Wu, Vincent W.C.; Yang Zhining; Zhang Wuzhe; Wu Lili; Lin Zhixiong

    2012-01-01

    This study compared the oral cavity dose between the routine 7-beam intensity-modulated radiotherapy (IMRT) beam arrangement and 2 other 7-beam IMRT with the conventional radiotherapy beam arrangements in the treatment of nasopharyngeal carcinoma (NPC). Ten NPC patients treated by the 7-beam routine IMRT technique (IMRT-7R) between April 2009 and June 2009 were recruited. Using the same computed tomography data, target information, and dose constraints for all the contoured structures, 2 IMRT plans with alternative beam arrangements (IMRT-7M and IMRT-7P) by avoiding the anterior facial beam and 1 conventional radiotherapy plan (CONRT) were computed using the Pinnacle treatment planning system. Dose-volume histograms were generated for the planning target volumes (PTVs) and oral cavity from which the dose parameters and the conformity index of the PTV were recorded for dosimetric comparisons among the plans with different beam arrangements. The dose distributions to the PTVs were similar among the 3 IMRT beam arrangements, whereas the differences were significant between IMRT-7R and CONRT plans. For the oral cavity dose, the 3 IMRT beam arrangements did not show significant difference. Compared with IMRT-7R, CONRT plan showed a significantly lower mean dose, V30 and V-40, whereas the V-60 was significantly higher. The 2 suggested alternative beam arrangements did not significantly reduce the oral cavity dose. The impact of varying the beam angles in IMRT of NPC did not give noticeable effect on the target and oral cavity. Compared with IMRT, the 2-D conventional radiotherapy irradiated a greater high-dose volume in the oral cavity.

  12. Dose-Volume Analysis of Radiation Nephropathy in Children: Preliminary Report of the Risk Consortium

    International Nuclear Information System (INIS)

    Boelling, Tobias; Ernst, Iris; Pape, Hildegard; Martini, Carmen; Ruebe, Christian; Timmermann, Beate; Fischedick, Karin; Kortmann, Rolf-Dieter; Willich, Normann

    2011-01-01

    Purpose: To characterize kidney function in children and adolescents who had undergone radiation treatment that included parts of the kidney. Methods and Materials: Patients receiving radiotherapy during childhood or adolescence were prospectively registered in Germany's Registry for the Evaluation of Side Effects after Radiation in Childhood and Adolescence (RiSK). Detailed information was recorded regarding radiation doses at the organs at risk since 2001 all over Germany. Toxicity evaluation was performed according to standardized Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Results: Up to May 2009, 1086 patients from 62 centers were recruited, including 126 patients (median age, 10.2 years) who underwent radiotherapy to parts of the kidneys. Maximal late toxicity (median follow-up 28.5 months in 74 patients) was characterized as Grade 0 (n = 65), 1 (n = 7) or 2 (n = 2). All patients with late effects had received potentially nephrotoxic chemotherapy. A statistically significant difference between patients with and without Grade 1 toxicity, revealing higher exposed kidney volumes in patients with toxicity, was seen for the kidney volume exposed to 20 Gy (V20; p = 0.031) and 30 Gy (V30; p = 0.003). Conclusions: Preliminary data indicate that radiation-induced kidney function impairment is rare in current pediatric multimodal treatment approaches. In the future, RiSK will be able to provide further detailed data regarding dose-volume effect relationships of radiation-associated side effects in pediatric oncology patients.

  13. Circumferential or sectored beam arrangements for stereotactic body radiation therapy (SBRT) of primary lung tumors: Effect on target and normal-structure dose-volume metrics

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Mara W. [Broad Institute of MIT and Harvard, Cambridge, MA (United States); Department of Physics, Brandeis University, Waltham, MA (United States); Kato, Catherine M. [Macalester College, St. Paul, MN (United States); Carson, Kelly M.P. [The University of North Carolina, Chapel Hill, NC (United States); Matsunaga, Nathan M. [Santa Clara University, Santa Clara, CA (United States); Arao, Robert F. [Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR (United States); Doss, Emily J. [Department of Internal Medicine, Providence St. Vincent Medical Center, Portland, OR (United States); McCracken, Charles L. [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Meng, Lu Z. [Department of Radiation Oncology, University of California Davis Comprehensive Cancer Center, Sacramento, CA (United States); Chen, Yiyi [Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR (United States); Laub, Wolfram U.; Fuss, Martin [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Corvallis, OR (United States); Tanyi, James A., E-mail: tanyij@ohsu.edu [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Corvallis, OR (United States)

    2013-01-01

    To compare 2 beam arrangements, sectored (beam entry over ipsilateral hemithorax) vs circumferential (beam entry over both ipsilateral and contralateral lungs), for static-gantry intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) delivery techniques with respect to target and organs-at-risk (OAR) dose-volume metrics, as well as treatment delivery efficiency. Data from 60 consecutive patients treated using stereotactic body radiation therapy (SBRT) for primary non–small-cell lung cancer (NSCLC) formed the basis of this study. Four treatment plans were generated per data set: IMRT/VMAT plans using sectored (-s) and circumferential (-c) configurations. The prescribed dose (PD) was 60 Gy in 5 fractions to 95% of the planning target volume (PTV) (maximum PTV dose ∼ 150% PD) for a 6-MV photon beam. Plan conformality, R{sub 50} (ratio of volume circumscribed by the 50% isodose line and the PTV), and D{sub 2} {sub cm} (D{sub max} at a distance ≥2 cm beyond the PTV) were evaluated. For lungs, mean doses (mean lung dose [MLD]) and percent V{sub 30}/V{sub 20}/V{sub 10}/V{sub 5} Gy were assessed. Spinal cord and esophagus D{sub max} and D{sub 5}/D{sub 50} were computed. Chest wall (CW) D{sub max} and absolute V{sub 30}/V{sub 20}/V{sub 10}/V{sub 5} {sub Gy} were reported. Sectored SBRT planning resulted in significant decrease in contralateral MLD and V{sub 10}/V{sub 5} {sub Gy}, as well as contralateral CW D{sub max} and V{sub 10}/V{sub 5} {sub Gy} (all p < 0.001). Nominal reductions of D{sub max} and D{sub 5}/D{sub 50} for the spinal cord with sectored planning did not reach statistical significance for static-gantry IMRT, although VMAT metrics did show a statistically significant decrease (all p < 0.001). The respective measures for esophageal doses were significantly lower with sectored planning (p < 0.001). Despite comparable dose conformality, irrespective of planning configuration, R{sub 50} significantly improved with IMRT

  14. The integral biologically effective dose to predict brain stem toxicity of hypofractionated stereotactic radiotherapy

    International Nuclear Information System (INIS)

    Clark, Brenda G.; Souhami, Luis; Pla, Conrado; Al-Amro, Abdullah S.; Bahary, Jean-Paul; Villemure, Jean-Guy; Caron, Jean-Louis; Olivier, Andre; Podgorsak, Ervin B.

    1998-01-01

    Purpose: The aim of this work was to develop a parameter for use during fractionated stereotactic radiotherapy treatment planning to aid in the determination of the appropriate treatment volume and fractionation regimen that will minimize risk of late damage to normal tissue. Materials and Methods: We have used the linear quadratic model to assess the biologically effective dose at the periphery of stereotactic radiotherapy treatment volumes that impinge on the brain stem. This paper reports a retrospective study of 77 patients with malignant and benign intracranial lesions, treated between 1987 and 1995, with the dynamic rotation technique in 6 fractions over a period of 2 weeks, to a total dose of 42 Gy prescribed at the 90% isodose surface. From differential dose-volume histograms, we evaluated biologically effective dose-volume histograms and obtained an integral biologically-effective dose (IBED) in each case. Results: Of the 77 patients in the study, 36 had target volumes positioned so that the brain stem received more than 1% of the prescribed dose, and 4 of these, all treated for meningioma, developed serious late damage involving the brain stem. Other than type of lesion, the only significant variable was the volume of brain stem exposed. An analysis of the IBEDs received by these 36 patients shows evidence of a threshold value for late damage to the brain stem consistent with similar thresholds that have been determined for external beam radiotherapy. Conclusions: We have introduced a new parameter, the IBED, that may be used to represent the fractional effective dose to structures such as the brain stem that are partially irradiated with stereotactic dose distributions. The IBED is easily calculated prior to treatment and may be used to determine appropriate treatment volumes and fractionation regimens minimizing possible toxicity to normal tissue

  15. Radiotherapy

    International Nuclear Information System (INIS)

    Wannenmacher, M.; Debus, J.; Wenz, F.

    2006-01-01

    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

  16. Radiotherapy.

    Science.gov (United States)

    Krause, Sonja; Debus, Jürgen; Neuhof, Dirk

    2011-01-01

    Solitary plasmocytoma occurring in bone (solitary plasmocytoma of the bone, SBP) or in soft tissue (extramedullary plasmocytoma, EP) can be treated effectively and with little toxicity by local radiotherapy. Ten-year local control rates of up to 90% can be achieved. Patients with multiple myeloma often suffer from symptoms such as pain or neurological impairments that are amenable to palliative radiotherapy. In a palliative setting, short treatment schedules and lower radiation doses are used to reduce toxicity and duration of hospitalization. In future, low-dose total body irradiation (TBI) may play a role in a potentially curative regimen with nonmyeloablative conditioning followed by allogenic peripheral blood stem cell transplantation.

  17. A comparison of dose-volume constraints derived using peak and longitudinal definitions of late rectal toxicity

    International Nuclear Information System (INIS)

    Gulliford, Sarah L.; Partridge, Mike; Sydes, Matthew R.; Andreyev, Jervoise; Dearnaley, David P.

    2010-01-01

    Background and purpose: Accurate reporting of complications following radiotherapy is an important part of the feedback loop to improve radiotherapy techniques. The definition of toxicity is normally regarded as the maximum or peak (P) grade of toxicity reported over the follow-up period. An alternative definition (integrated longitudinal toxicity (ILT)) is proposed which takes into account both the severity and the duration of the complication. Methods and materials: In this work, both definitions of toxicity were used to derive dose-volume constraints for six specific endpoints of late rectal toxicity from a cohort of patients who received prostate radiotherapy in the MRC RT01 trial. The dose-volume constraints were derived using ROC analysis for 30, 40, 50, 60, 65 and 70 Gy. Results: Statistically significant dose-volume constraints were not derived for all dose levels tested for each endpoint and toxicity definition. However, where both definitions produced constraints, there was generally good agreement. Variation in the derived dose-volume constraints was observed to be larger between endpoints than between the two definitions of toxicity. For one endpoint (stool frequency (LENT/SOM)) statistically significant dose-volume constraints were only derived using ILT. Conclusions: The longitudinal definition of toxicity (ILT) produced results consistent with those derived using peak toxicity and in some cases provided additional information which was not seen by analysing peak toxicity alone.

  18. Calculation of complication probability of pion treatment at PSI using dose-volume histograms

    International Nuclear Information System (INIS)

    Nakagawa, Keiichi; Akanuma, Atsuo; Aoki, Yukimasa

    1991-01-01

    In the conformation technique a target volume is irradiated uniformly as in conventional radiations, whereas surrounding tissue and organs are nonuniformly irradiated. Clinical data on radiation injuries that accumulate with conventional radiation are not applicable without appropriate compensation. Recently a putative solution of this problem was proposed by Lyman using dose-volume histograms. This histogram reduction method reduces a given dose-volume histogram of an organ to a single step which corresponds to the equivalent complication probability by interpolation. As a result it converts nonuniform radiation into a unique dose to the whole organ which has the equivalent likelihood of radiation injury. This method is based on low LET radiation with conventional fractionation schedules. When it is applied to high LET radiation such as negative pion treatment, a high LET dose should be converted to an equivalent photon dose using an appropriate value of RBE. In the present study the histogram reduction method was applied to actual patients treated by the negative pion conformation technique at the Paul Scherrer Institute. Out of evaluable 90 cases of pelvic tumors, 16 developed grade III-IV bladder injury, and 7 developed grade III-IV rectal injury. The 90 cases were divided into roughly equal groups according to the equivalent doses to the entire bladder and rectum. Complication rates and equivalent doses to the full organs in these groups could be represented by a sigmoid dose-effect relation. When RBE from a pion dose to a photon dose is assumed to be 2.1 for bladder injury, the rates of bladder complications fit best to the theoretical complication curve. When the RBE value was 2.3, the rates of rectal injury fit the theoretical curve best. These values are close to the conversion factor of 2.0 that is used in clinical practice at PSI. This agreement suggests the clinical feasibility of the histogram reduction method in conformation radiotherapy. (author)

  19. Effect of radiotherapy on immunity function of cancer patients receiving radiotherapy

    International Nuclear Information System (INIS)

    Li Xinli; Zhu Shentao; Xu Jiuhong

    2003-01-01

    Objective: In order to observe the effect of radiotherapy on immunity function of cancer patients receiving radiotherapy. Methods: Cellular immunity is determined by APAAP; Humoral immunity is determined by transmission method. Results: The items of cellular immunity is lower than the control after radiotherapy. These items decrease continually. The difference between before and after radiotherapy has statistic significance. Of all Humoral immunity items, IgA, IgM decreased after radiotherapy and the difference has statistic significance. Conclusions: Radiotherapy can damage patients' immunity function

  20. Decomposition analysis of differential dose volume histograms

    International Nuclear Information System (INIS)

    Heuvel, Frank van den

    2006-01-01

    Dose volume histograms are a common tool to assess the value of a treatment plan for various forms of radiation therapy treatment. The purpose of this work is to introduce, validate, and apply a set of tools to analyze differential dose volume histograms by decomposing them into physically and clinically meaningful normal distributions. A weighted sum of the decomposed normal distributions (e.g., weighted dose) is proposed as a new measure of target dose, rather than the more unstable point dose. The method and its theory are presented and validated using simulated distributions. Additional validation is performed by analyzing simple four field box techniques encompassing a predefined target, using different treatment energies inside a water phantom. Furthermore, two clinical situations are analyzed using this methodology to illustrate practical usefulness. A comparison of a treatment plan for a breast patient using a tangential field setup with wedges is compared to a comparable geometry using dose compensators. Finally, a normal tissue complication probability (NTCP) calculation is refined using this decomposition. The NTCP calculation is performed on a liver as organ at risk in a treatment of a mesothelioma patient with involvement of the right lung. The comparison of the wedged breast treatment versus the compensator technique yields comparable classical dose parameters (e.g., conformity index ≅1 and equal dose at the ICRU dose point). The methodology proposed here shows a 4% difference in weighted dose outlining the difference in treatment using a single parameter instead of at least two in a classical analysis (e.g., mean dose, and maximal dose, or total dose variance). NTCP-calculations for the mesothelioma case are generated automatically and show a 3% decrease with respect to the classical calculation. The decrease is slightly dependant on the fractionation and on the α/β-value utilized. In conclusion, this method is able to distinguish clinically

  1. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Science.gov (United States)

    Shi, Chengyu; Guo, Bingqi; Cheng, Chih-Yao; Eng, Tony; Papanikolaou, Nikos

    2010-09-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent™ x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  2. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos [Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, TX 78229 (United States); Cheng, Chih-Yao, E-mail: shic@uthscsa.ed [Radiation Oncology Department, Oklahoma University Health Science Center, Oklahoma, OK 73104 (United States)

    2010-09-21

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V{sub 100} reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as

  3. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    International Nuclear Information System (INIS)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos; Cheng, Chih-Yao

    2010-01-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V 100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  4. A novel method for the evaluation of uncertainty in dose-volume histogram computation.

    Science.gov (United States)

    Henríquez, Francisco Cutanda; Castrillón, Silvia Vargas

    2008-03-15

    Dose-volume histograms (DVHs) are a useful tool in state-of-the-art radiotherapy treatment planning, and it is essential to recognize their limitations. Even after a specific dose-calculation model is optimized, dose distributions computed by using treatment-planning systems are affected by several sources of uncertainty, such as algorithm limitations, measurement uncertainty in the data used to model the beam, and residual differences between measured and computed dose. This report presents a novel method to take them into account. To take into account the effect of associated uncertainties, a probabilistic approach using a new kind of histogram, a dose-expected volume histogram, is introduced. The expected value of the volume in the region of interest receiving an absorbed dose equal to or greater than a certain value is found by using the probability distribution of the dose at each point. A rectangular probability distribution is assumed for this point dose, and a formulation that accounts for uncertainties associated with point dose is presented for practical computations. This method is applied to a set of DVHs for different regions of interest, including 6 brain patients, 8 lung patients, 8 pelvis patients, and 6 prostate patients planned for intensity-modulated radiation therapy. Results show a greater effect on planning target volume coverage than in organs at risk. In cases of steep DVH gradients, such as planning target volumes, this new method shows the largest differences with the corresponding DVH; thus, the effect of the uncertainty is larger.

  5. WE-B-304-02: Treatment Planning Evaluation and Optimization Should Be Biologically and Not Dose/volume Based

    International Nuclear Information System (INIS)

    Deasy, J.

    2015-01-01

    The ultimate goal of radiotherapy treatment planning is to find a treatment that will yield a high tumor control probability (TCP) with an acceptable normal tissue complication probability (NTCP). Yet most treatment planning today is not based upon optimization of TCPs and NTCPs, but rather upon meeting physical dose and volume constraints defined by the planner. It has been suggested that treatment planning evaluation and optimization would be more effective if they were biologically and not dose/volume based, and this is the claim debated in this month’s Point/Counterpoint. After a brief overview of biologically and DVH based treatment planning by the Moderator Colin Orton, Joseph Deasy (for biological planning) and Charles Mayo (against biological planning) will begin the debate. Some of the arguments in support of biological planning include: this will result in more effective dose distributions for many patients DVH-based measures of plan quality are known to have little predictive value there is little evidence that either D95 or D98 of the PTV is a good predictor of tumor control sufficient validated outcome prediction models are now becoming available and should be used to drive planning and optimization Some of the arguments against biological planning include: several decades of experience with DVH-based planning should not be discarded we do not know enough about the reliability and errors associated with biological models the radiotherapy community in general has little direct experience with side by side comparisons of DVH vs biological metrics and outcomes it is unlikely that a clinician would accept extremely cold regions in a CTV or hot regions in a PTV, despite having acceptable TCP values Learning Objectives: To understand dose/volume based treatment planning and its potential limitations To understand biological metrics such as EUD, TCP, and NTCP To understand biologically based treatment planning and its potential limitations

  6. SU-F-T-378: Evaluation of Dose-Volume Variability and Parameters Between Prostate IMRT and VMAT Plans

    Energy Technology Data Exchange (ETDEWEB)

    Chow, J [Princess Margaret Cancer Centre, Toronto, ON (Canada); Jiang, R [Grand River Regional Cancer Centre, Kitchener, ON (Canada); Kiciak, A [University of Waterloo, Waterloo, ON (Canada)

    2016-06-15

    Purpose: This study compared the rectal dose-volume consistency, equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) in prostate intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Methods: For forty prostate IMRT and fifty VMAT patients treated using the same dose prescription (78 Gy/39 fraction) and dose-volume criteria in inverse planning optimization, the rectal EUD and NTCP were calculated for each patient. The rectal dose-volume consistency, showing the variability of dose-volume histogram (DVH) among patients, was defined and calculated based on the deviation between the mean and corresponding rectal DVH. Results: From both the prostate IMRT and VMAT plans, the rectal EUD and NTCP were found decreasing with the rectal volume. The decrease rates for the IMRT plans (EUD = 0.47 × 10{sup −3} Gy cm{sup −3} and NTCP = 3.94 × 10{sup −2} % cm{sup −3}) were higher than those for the VMAT (EUD = 0.28 × 10{sup −3} Gy cm{sup −3} and NTCP = 2.61 × 10{sup −2} % cm{sup −3}). In addition, the dependences of the rectal EUD and NTCP on the dose-volume consistency were found very similar between the prostate IMRT and VMAT plans. This shows that both delivery techniques have similar variations of the rectal EUD and NTCP on the dose-volume consistency. Conclusion: Dependences of the dose-volume consistency on the rectal EUD and NTCP were compared between the prostate IMRT and VMAT plans. It is concluded that both rectal EUD and NTCP decreased with an increase of the rectal volume. The variation rates of the rectal EUD and NTCP on the rectal volume were higher for the IMRT plans than VMAT. However, variations of the rectal dose-volume consistency on the rectal EUD and NTCP were found not significant for both delivery techniques.

  7. Combined effects of radiotherapy and non-specific immunotherapy

    International Nuclear Information System (INIS)

    Yamashita, Takashi; Hayakawa, Yukiko; Mochizuki, Yukio

    1985-01-01

    Local and systemic effects of the combined use of radiotherapy and administration of OK-432 were examined using tumor-bearing mice. Tumor regrowth was inhibited by local administration of OK-432 following radiotherapy. Systemic inhibitory effects of OK-432 on tumors were not seen. When radiotherapy is performed in combination with administration of OK-432, synergistic effects will be observed. (Namekawa, K.)

  8. Radiotherapy

    International Nuclear Information System (INIS)

    Prosnitz, L.R.; Kapp, D.S.; Weissberg, J.B.

    1983-01-01

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

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

    International Nuclear Information System (INIS)

    Chen Jinsheng; Jiang Yuanshi; Cao Xibiao; Zhan Yongzhong; Yang Liye; Chen Jianxiu; Chen Chengwu; Li Yang

    2003-01-01

    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

  10. Reliability of dose volume constraint inference from clinical data

    Science.gov (United States)

    Lutz, C. M.; Møller, D. S.; Hoffmann, L.; Knap, M. M.; Alber, M.

    2017-04-01

    Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an ‘ideal’ cohort was generated where the most predictive model was equal to the postulated model. A bootstrap and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling with replacement) and three postulated DVHP models. The Bootstrap was repeated for a ‘non-ideal’ cohort, where the most predictive model did not coincide with the postulated model. The Bootstrap produced chaotic results for all models of cohort size 1 for both the ideal and non-ideal cohorts. For cohort size 2 and 3, the distributions for all populations were more concentrated around the postulated DVHP. For the CoRepMC, the inference frequency increased with cohort size and incidence rate. Correct inference rates  >85 % were only achieved by cohorts with more than 500 patients. Both Bootstrap and CoRepMC indicate that inference of the correct or approximate DVHP for typical cohort sizes is highly uncertain. CoRepMC results were less spurious than Bootstrap results, demonstrating the large influence that randomness in dose-response has on the statistical analysis.

  11. Dose-volume histogram analysis of hepatic toxicity related to carbon ion radiation therapy of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Yasuda, Shigeo; Kato, Hirotoshi; Tsujii, Hitohiko; Mizoe, Junetsu

    2005-01-01

    The purpose of this study is to analyze the correlation of hepatic toxicity with dose-volume factors of carbon ion radiotherapy in the liver. Forty-nine patients with hepatocellular carcinoma were treated with carbon ion radiotherapy delivered in 4 fractions over 4 to 7 days. Six patients received a total dose of 48 GyE and 43 received 52.8 GyE. The correlation of various blood biochemistry data with dose-volume histogram (DVH) data in non-cancerous liver were evaluated. The strongest significant correlation was seen between percent volume of non-cancerous liver with radiation dose more than 11 GyE (V 11 GyE ) and elevation of serum glutamic oxaloacetic transaminase (GOT) level as early adverse response after carbon ion beam radiation therapy (p=0.0003). In addition, significant correlation between DVH data and change of several other blood biochemistry data were also revealed in early phase. In late phase after carbon ion radiotherapy, the strongest significant correlation was seen between decrease of platelet count and V 26GyE (p=0.015). There was no significant correlation between other blood biochemistry data and DVH data in the late phase. It was suggested that dose-volume factors of carbon ion radiotherapy influenced only transient aggravation of liver function, which improved in the long term after irradiation. (author)

  12. Dose-volume considerations in stereotaxic brain radiation therapy

    International Nuclear Information System (INIS)

    Houdek, P.V.; Schwade, J.G.; Pisciotta, V.J.; Medina, A.J.; Lewin, A.A.; Abitbol, A.A.; Serago, C.F.

    1988-01-01

    Although brain radiation therapy experience suggests that a gain in the therapeutic ratio may be achieved by optimizing the dose-volume relationship, no practical system for quantitative assessment of dose-volume data has been developed. This presentation describes the rationale for using the integral dose function for this purpose and demonstrates that with the use of a conventional treatment planning computer and a series of computed tomographic scans, first-order optimization of the dose-volume function can be accomplished in two steps: first, high-dose volume is minimized by selecting an appropriate treatment technique and tumor margin, and then dosage is maximized by calculating the brain tolerance dose as a function of the irradiated volume

  13. Radiotherapy

    Directory of Open Access Journals (Sweden)

    Rema Jyothirmayi

    1999-01-01

    Full Text Available Purpose. Conservative treatment in the form of limited surgery and post-operative radiotherapy is controversial in hand and foot sarcomas, both due to poor radiation tolerance of the palm and sole, and due to technical difficulties in achieving adequate margins.This paper describes the local control and survival of 41 patients with soft tissue sarcoma of the hand or foot treated with conservative surgery and radiotherapy. The acute and late toxicity of megavoltage radiotherapy to the hand and foot are described. The technical issues and details of treatment delivery are discussed. The factors influencing local control after radiotherapy are analysed.

  14. Effects of low dose mitomycin C on experimental tumor radiotherapy

    International Nuclear Information System (INIS)

    Yang Jianzheng; Liang Shuo; Qu Yaqin; Pu Chunji; Zhang Haiying; Wu Zhenfeng; Wang Xianli

    2001-01-01

    Objective: To evaluate the possibility of low dose mitomycin C(MMC) as an adjunct therapy for radiotherapy. Methods: Change in tumor size tumor-bearing mice was measured. Radioimmunoassay was used to determine immune function of mice. Results: Low dose Mac's pretreatment reduced tumor size more markedly than did radiotherapy only. The immune function in mice given with low dose MMC 12h before radiotherapy was obviously higher than that in mice subjected to radiotherapy only (P<0.05), and was close to that in the tumor-bearing mice before radiotherapy. Conclusion: Low dose MMC could improve the radiotherapy effect. Pretreatment with low dose MMC could obviously improve the immune suppression state in mice caused by radiotherapy. The mechanism of its improvement of radiotherapeutic effect by low dose of MMC might be due to its enhancement of immune function and induction of adaptive response in tumor-bearing mice

  15. Evaluation of different set-up error corrections on dose-volume metrics in prostate IMRT using CBCT images

    International Nuclear Information System (INIS)

    Hirose, Yoshinori; Tomita, Tsuneyuki; Kitsuda, Kenji; Notogawa, Takuya; Miki, Katsuhito; Nakamura, Mitsuhiro; Nakamura, Kiyonao; Ishigaki, Takashi

    2014-01-01

    We investigated the effect of different set-up error corrections on dose-volume metrics in intensity-modulated radiotherapy (IMRT) for prostate cancer under different planning target volume (PTV) margin settings using cone-beam computed tomography (CBCT) images. A total of 30 consecutive patients who underwent IMRT for prostate cancer were retrospectively analysed, and 7-14 CBCT datasets were acquired per patient. Interfractional variations in dose-volume metrics were evaluated under six different set-up error corrections, including tattoo, bony anatomy, and four different target matching groups. Set-up errors were incorporated into planning the isocenter position, and dose distributions were recalculated on CBCT images. These processes were repeated under two different PTV margin settings. In the on-line bony anatomy matching groups, systematic error (Σ) was 0.3 mm, 1.4 mm, and 0.3 mm in the left-right, anterior-posterior (AP), and superior-inferior directions, respectively. Σ in three successive off-line target matchings was finally comparable with that in the on-line bony anatomy matching in the AP direction. Although doses to the rectum and bladder wall were reduced for a small PTV margin, averaged reductions in the volume receiving 100% of the prescription dose from planning were within 2.5% under all PTV margin settings for all correction groups, with the exception of the tattoo set-up error correction only (≥ 5.0%). Analysis of variance showed no significant difference between on-line bony anatomy matching and target matching. While variations between the planned and delivered doses were smallest when target matching was applied, the use of bony anatomy matching still ensured the planned doses. (author)

  16. Delayed somatic effects following extended radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Slanina, J

    1977-10-27

    A group of 135 patients was investigated, who suffered from Hodgkin's disease with long-term remission following radiotherapy. By restricting the investigations to the patient group with long-term remission and correlative examinations, differentiation was made between exclusive or principal delayed radiation effects and delayed effects due to other factors. The study reports the most significant results obtained in the fields of catamnesis, laboratory diagnostics, hematology, pulmology, cardiology, thyroid function tests, neurology, andrology and dermatology. Due to the numerous detectable delayed effects the group of patients with long-term remission receives a special status. Although those effects are in no proportion to the deletary risks of an untreated Hodgkin's disease and though they are consequently tolerable in the present state of the therapeutic development, they must initiate the completion of the therapeutic concept including performance of radiotherapy and aftercare, because only then the risk for the patient provoked by these effects, which ranges beyond the malignity of this disease can be reduced or prevented.

  17. Effect of radiotherapy on gustation

    International Nuclear Information System (INIS)

    Soni, N.K.; Chatterji, P.

    1988-01-01

    Effect of radiation on the sense of taste was assessed in a group of 30 patients with head and neck malignancy. The taste threshold was determined by an electrogustometer. The results obtained are presented. Almost all the patients showed some degree of impaired taste sensation, and this was shown to be related to the dosages of irradiation and to some extent to the age of the person. The sense of taste deteriorated rapidly during second week, i.e., with a dose of 2000 rads and more marked during third week (3000 rads), subsequently reaching to a stable stage. Recovery is gradual and by 24-30 weeks, in about 50 per cent of the persons. The possible reasons for loss of the taste sensation are discussed. (author). 8 refs., 7 tables

  18. Secondary effects of radiotherapy on the orofacial sphere

    International Nuclear Information System (INIS)

    Guillaume, Nicolas

    2012-01-01

    The objective of this research is to determine the role of the dental surgeon in the taking into care of patients treated by head and neck radiotherapy. It also aims at giving information to the patient on secondary effects which radiotherapy may induce, and at determining which therapeutic behaviour to adopt to prevent or at least mitigate the appearance of complications. The author first presents some generalities on radiotherapy: presentation of upper aero-digestive tract cancers (surgery, radiotherapy, and chemotherapy), description of the different radiotherapy techniques (external radiotherapy, brachytherapy), discussion of factors influencing local secondary effects of radiotherapy. The second part addresses the specific case of early orofacial secondary effects, discusses their origin, clinic signs and prevention means: cutaneous effect, mucositis, xerostomia, candidiasis, taste disorders, relationship between early local reactions and anti-tumour treatment efficiency. The third part addresses late orofacial secondary effects: cervix sclerosis, limitation of mouth opening, dental effects, periodontal diseases, osteoradionecrosis. The last part discusses the evolution of radiotherapy: intensity modulated conformational radiotherapy, targeted therapeutics [fr

  19. The effectiveness of radiotherapy for Merkel cell carcinoma

    International Nuclear Information System (INIS)

    Wakisaka, Masaki; Mori, Hiromu; Monzen, Yoshio; Aikawa, Hisayuki; Miyake, Hidetoshi; Ashizawa, Akira; Okamoto, Osamu; Yoshiyama, Masako; Takayasu, Susumu

    1992-01-01

    Merkel cell carcinoma is a high-grade malignant tumor of the skin that tends to extend locally and metastasize to regional lymph nodes. Surgical resection is the treatment of choice, and the effectiveness of radiotherapy for this disease has not yet been established. We report two cases of biopsy-proven Merkel cell carcinoma effectively treated with radiotherapy. Histopathological examination of the resected specimens after radiotherapy of 50 Gy and 38 Gy, respectively, using 6∼15 MeV electrons showed no malignant cells in either case. No evidence of recurrence or metastasis has been noted in 11 to 21 months after radiotherapy. To our knowledge, no case of Merkel cell carcinoma in which complete cure was obtained by radiotherapy alone has been reported previously. It is considered that preoperative radiotherapy would contribute to the management of this locally invasive but radiosensitive tumor. (author)

  20. Estimation of pneumonitis risk in three-dimensional treatment planning using dose-volume histogram analysis

    International Nuclear Information System (INIS)

    Oetzel, Dieter; Schraube, Peter; Hensley, Frank; Sroka-Perez, Gabriele; Menke, Markus; Flentje, Michael

    1995-01-01

    Purpose: Investigations to study correlations between the estimations of biophysical models in three dimensional (3D) treatment planning and clinical observations are scarce. The development of clinically symptomatic pneumonitis in the radiotherapy of thoracic malignomas was chosen to test the predictive power of Lyman's normal tissue complication probability (NTCP) model for the assessment of side effects for nonuniform irradiation. Methods and Materials: In a retrospective analysis individual computed-tomography-based 3D dose distributions of a random sample of (46(20)) patients with lung/esophageal cancer were reconstructed. All patients received tumor doses between 50 and 60 Gy in a conventional treatment schedule. Biological isoeffective dose-volume histograms (DVHs) were used for the calculation of complication probabilities after applying Lyman's and Kutcher's DVH-reduction algorithm. Lung dose statistics were performed for single lung (involved ipsilateral and contralateral) and for the lung as a paired organ. Results: In the lung cancer group, about 20% of the patients (9 out of 46) developed pneumonitis 3-12 (median 7.5) weeks after completion of radiotherapy. For the majority of these lung cancer patients, the involved ipsilateral lung received a much higher dose than the contralateral lung, and the pneumonitis patients had on average a higher lung exposure with a doubling of the predicted complication risk (38% vs. 20%). The lower lung exposure for the esophagus patients resulted in a mean lung dose of 13.2 Gy (lung cancer: 20.5 Gy) averaged over all patients in correlation with an almost zero complication risk and only one observed case of pneumonitis (1 out of 20). To compare the pneumonitis risk estimations with observed complication rates, the patients were ranked into bins of mean ipsilateral lung dose. Particularly, in the bins with the highest patient numbers, a good correlation was achieved. Agreement was not reached for the lung functioning as

  1. The effect of planning algorithms in oesophageal radiotherapy in the context of the SCOPE 1 trial

    International Nuclear Information System (INIS)

    Wills, Lucy; Millin, Anthony; Paterson, Jennifer; Crosby, Tom; Staffurth, John

    2009-01-01

    Background and purpose: In radiotherapy clinical trials multiple centres contribute to patient recruitment. Depending on the calculation algorithm used, the reported dose distributions may differ significantly: broadly, the results for algorithms which do not model lateral electron transport (type a) give less accurate results than the more recently available algorithms that do (type b) when compared to Monte Carlo simulations and measurements. Clinical implementation studies for type b algorithms have yet to be reported for oesophageal radiotherapy. Furthermore, clinical trials must ensure an equivalent effect of the treatment regardless of calculation method. This retrospective planning study aims to define guidance for type b planning in a UK oesophageal clinical trial, to enable acceptable consistency of dose distributions regardless of algorithm, and allow for the improved calculation accuracy of type b to be incorporated into the optimization. Materials and methods: Fifteen patient data sets were planned using a single type a algorithm. Plans were recalculated using a single type b algorithm and subsequently re-optimized with the type b in accordance with optimization rules. The changes in absolute dose at the point of prescription for type a were compared to the recalculated type b. Dose-volume data for organs at risk (OARs), and target volumes were compared, and the volume of the planning target volume (PTV) receiving 95% of the prescribed dose (V95%) was compared to the percentage of PTV overlapping with lung. Results: Dose at the prescription point decreased by 0.69% on average (SD = 0.71), p = 0.0021, for type b compared to that for type a. For the re-optimized type b, the OAR doses corresponding to the trial dose-volume constraints were maintained within 1.0% of the type a levels on average. Reductions in the mean PTV V95% of 9.3% and 3.8% were observed for the recalculated and re-optimized type b plans, respectively, when compared to the mean PTV V95

  2. Psychosocial effects of radiotherapy after mastectomy

    International Nuclear Information System (INIS)

    Hughson, A.V.M.; Cooper, A.F.; Smith, D.C.; McArdle, C.S.

    1987-01-01

    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)

  3. Normal tissue complication probabilities: dependence on choice of biological model and dose-volume histogram reduction scheme

    International Nuclear Information System (INIS)

    Moiseenko, Vitali; Battista, Jerry; Van Dyk, Jake

    2000-01-01

    Purpose: To evaluate the impact of dose-volume histogram (DVH) reduction schemes and models of normal tissue complication probability (NTCP) on ranking of radiation treatment plans. Methods and Materials: Data for liver complications in humans and for spinal cord in rats were used to derive input parameters of four different NTCP models. DVH reduction was performed using two schemes: 'effective volume' and 'preferred Lyman'. DVHs for competing treatment plans were derived from a sample DVH by varying dose uniformity in a high dose region so that the obtained cumulative DVHs intersected. Treatment plans were ranked according to the calculated NTCP values. Results: Whenever the preferred Lyman scheme was used to reduce the DVH, competing plans were indistinguishable as long as the mean dose was constant. The effective volume DVH reduction scheme did allow us to distinguish between these competing treatment plans. However, plan ranking depended on the radiobiological model used and its input parameters. Conclusions: Dose escalation will be a significant part of radiation treatment planning using new technologies, such as 3-D conformal radiotherapy and tomotherapy. Such dose escalation will depend on how the dose distributions in organs at risk are interpreted in terms of expected complication probabilities. The present study indicates considerable variability in predicted NTCP values because of the methods used for DVH reduction and radiobiological models and their input parameters. Animal studies and collection of standardized clinical data are needed to ascertain the effects of non-uniform dose distributions and to test the validity of the models currently in use

  4. Retrospective Reconstructions of Active Bone Marrow Dose-Volume Histograms

    International Nuclear Information System (INIS)

    Veres, Cristina; Allodji, Rodrigue S.; Llanas, Damien; Vu Bezin, Jérémi; Chavaudra, Jean; Mège, Jean Pierre; Lefkopoulos, Dimitri; Quiniou, Eric; Deutsh, Eric; Vathaire, Florent de; Diallo, Ibrahima

    2014-01-01

    Purpose: To present a method for calculating dose-volume histograms (DVH's) to the active bone marrow (ABM) of patients who had undergone radiation therapy (RT) and subsequently developed leukemia. Methods and Materials: The study focuses on 15 patients treated between 1961 and 1996. Whole-body RT planning computed tomographic (CT) data were not available. We therefore generated representative whole-body CTs similar to patient anatomy. In addition, we developed a method enabling us to obtain information on the density distribution of ABM all over the skeleton. Dose could then be calculated in a series of points distributed all over the skeleton in such a way that their local density reflected age-specific data for ABM distribution. Dose to particular regions and dose-volume histograms of the entire ABM were estimated for all patients. Results: Depending on patient age, the total number of dose calculation points generated ranged from 1,190,970 to 4,108,524. The average dose to ABM ranged from 0.3 to 16.4 Gy. Dose-volume histograms analysis showed that the median doses (D 50% ) ranged from 0.06 to 12.8 Gy. We also evaluated the inhomogeneity of individual patient ABM dose distribution according to clinical situation. It was evident that the coefficient of variation of the dose for the whole ABM ranged from 1.0 to 5.7, which means that the standard deviation could be more than 5 times higher than the mean. Conclusions: For patients with available long-term follow-up data, our method provides reconstruction of dose-volume data comparable to detailed dose calculations, which have become standard in modern CT-based 3-dimensional RT planning. Our strategy of using dose-volume histograms offers new perspectives to retrospective epidemiological studies

  5. Effects of Yifukang Oral Liquid on Chemotherapy- and Radiotherapy ...

    African Journals Online (AJOL)

    Purpose: To investigate the effects of Yifukang oral liquid (YFKOL) on chemotherapy- and radiotherapy-induced myelosuppression, leucopenia and gastrointestinal tract disturbances. Methods: The effects of YFKOL on myelosuppression, leucopenia and gastrointestinal tract disturbances were assessed by ...

  6. Radiotherapy

    International Nuclear Information System (INIS)

    Pistenma, D.A.

    1980-01-01

    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

  7. Cardiac Side-effects From Breast Cancer Radiotherapy.

    Science.gov (United States)

    Taylor, C W; Kirby, A M

    2015-11-01

    Breast cancer radiotherapy reduces the risk of cancer recurrence and death. However, it usually involves some radiation exposure of the heart and analyses of randomised trials have shown that it can increase the risk of heart disease. Estimates of the absolute risks of radiation-related heart disease are needed to help oncologists plan each individual woman's treatment. The risk for an individual woman varies according to her estimated cardiac radiation dose and her background risk of ischaemic heart disease in the absence of radiotherapy. When it is known, this risk can then be compared with the absolute benefit of the radiotherapy. At present, many UK cancer centres are already giving radiotherapy with mean heart doses of less than 3 Gy and for most women the benefits of the radiotherapy will probably far outweigh the risks. Technical approaches to minimising heart dose in breast cancer radiotherapy include optimisation of beam angles, use of multileaf collimator shielding, intensity-modulated radiotherapy, treatment in a prone position, treatment in deep inspiration (including the use of breath-hold and gating techniques), proton therapy and partial breast irradiation. The multileaf collimator is suitable for many women with upper pole left breast cancers, but for women with central or lower pole cancers, breath-holding techniques are now recommended in national UK guidelines. Ongoing work aims to identify ways of irradiating pan-regional lymph nodes that are effective, involve minimal exposure of organs at risk and are feasible to plan, deliver and verify. These will probably include wide tangent-based field-in-field intensity-modulated radiotherapy or arc radiotherapy techniques in combination with deep inspiratory breath-hold, and proton beam irradiation for women who have a high predicted heart dose from intensity-modulated radiotherapy. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  8. Late intestinal adverse effects of radiotherapy for uterine cervical cancer

    International Nuclear Information System (INIS)

    Tsukada, Seiji; Yamamoto, Yasuaki; Kaneko, Toru; Maruhashi, Toshihiro; Takahashi, Takeshi

    1993-01-01

    We investigated the incidence and clinical appearance of late adverse intestinal effects in 88 patients treated with postoperative radiotherapy and 46 patients treated with radiotherapy alone for uterine cervical cancer. In the postoperative radiotherapy group, colitis, ileus and bowel fistules were seen in 13 patients (14.8%), 8 (9.1%), and 3 (3.4%) of the patients, respectively. Of these patients, 11 (12.5%) needed to have surgical therapy for these adverse effects. In the radiation alone group, 18 patients (39.1%) had colitis and 2 (4.3%) had ileus; of them, 2 patients (4.3%) needed to have surgical therapy. The higher incidence of so severe adverse effects as to require surgical therapy in the postoperative radiotherapy group indicates that adhesion caused by operation might have caused the occurrence of these adverse effects. Four of a total of 134 patients died of causes which might be attributable to irradiation. In 61 patients treated by radical hysterectomy without postoperative radiotherapy, intestinal adverse effects were not found. These results indicate that late intestinal adverse effects after radiotherapy are likely to occur in some cases very severely; therefore, careful consideration is necessary in the decision to use radiotherpay for uterine cervical cancer. (J.P.N.)

  9. Effects of radiotherapy on olfactory function

    International Nuclear Information System (INIS)

    Hoelscher, Tobias; Seibt, Annedore; Appold, Steffen; Doerr, Wolfgang; Herrmann, Thomas; Huettenbrink, Karl-Bernd; Hummel, Thomas

    2005-01-01

    Background and Purpose: Changes in olfactory function have been reported in patients receiving significant doses of radiation to the olfactory epithelium. Aim of this study was to investigate severity and time course of changes in olfactory function in patients irradiated for tumours of the head and neck region. Material and Methods: Forty-four patients receiving radiotherapy (RT) for tumours in the area of the head and neck participated (16 women, 28 men; age 11-81 y; mean 55 y). Olfactory function was measured before and bi-weekly during RT for 6 weeks. A subgroup (25 patients) was followed for 12 months. Patients were divided into two groups according to the dose to the olfactory epithelium. Twenty-two patients ('OLF group') had radiation doses to the olfactory epithelium between 23.7 and 79.5 Gy (median 62.2 Gy). In the 22 patients of the 'non-OLF group' the dose applied to the olfactory epithelium was significantly lower (2.9-11.1 Gy, median 5.9 Gy). Total tumour dose (30-76.8 Gy), age, sex distribution, and baseline chemosensory function were not significantly different between groups. Testing was performed for odour identification, odour discrimination, and olfactory thresholds. Results: Odour discrimination, but not odour identification or odour threshold, was significantly decreased 2-6 weeks after begin of therapy in the OLF group. In addition, a significant effect of the radiation dose was observed for odour discrimination. More than 6 months after therapy, OLF group patients had significantly lower odour identification scores compared to the non-OLF group. Conclusion: As indicated through the non-significant change of olfactory thresholds, the olfactory epithelium is relatively resistant against effects of radiation. It is hypothesized that RT has additional effects on the olfactory bulb/orbitofrontal cortex responsible for the observed changes of suprathreshold olfactory function

  10. Hypothyroidism After Head-and-Neck Radiotherapy in Children and Adolescents: Preliminary Results of the 'Registry for the Evaluation of Side Effects After Radiotherapy in Childhood and Adolescence' (RiSK)

    Energy Technology Data Exchange (ETDEWEB)

    Boelling, Tobias, E-mail: Tobias.Boelling@uni-muenster.de [Department of Radiotherapy, University Hospital of Muenster, Muenster (Germany); Department of Radiotherapy, Paracelsus Clinic Osnabrueck, Osnabrueck (Germany); Geisenheiser, Alina [Department of Radiotherapy, University Hospital of Muenster, Muenster (Germany); Pape, Hildegard [Department of Radiotherapy, University Hospital of Duesseldorf, Duesseldorf (Germany); Martini, Carmen [Department of Radiotherapy, University Hospital of Freiburg, Freiburg (Germany); Ruebe, Christian [Department of Radiotherapy, University Hospital of Homburg/Saar, Homburg/Saar (Germany); Timmermann, Beate [Center for Proton Radiation Therapy, Paul-Scherrer-Institute, Villigen (Switzerland); Fischedick, Karin [Department of Radiotherapy, University of Aachen, Aachen (Germany); Kortmann, Rolf-Dieter [Department of Radiotherapy, University of Leipzig, Leipzig (Germany); Gerss, Joachim; Koch, Raphael [Department of Medical Informatics and Biomathematics, University of Muenster, Muenster (Germany); Center for Clinical Trials, University Hospital of Muenster, Muenster (Germany); Willich, Normann [Department of Radiotherapy, University Hospital of Muenster, Muenster (Germany)

    2011-12-01

    Purpose: The 'Registry for the Evaluation of Side Effects After Radiotherapy in Childhood and Adolescence' (RiSK) has been established to prospectively characterize dose-volume effects of radiation in terms of side effects. The aim of this analysis was to characterize the function of the thyroid gland after radiotherapy to the head-and-neck region in children and adolescents. Methods and Materials: Detailed information regarding radiation doses to at-risk organs has been collected across Germany since 2001. Thyroid function was evaluated by blood value examinations of thyroid-stimulating hormone, triiodothyronine, and thyroxine. Information regarding thyroid hormone substitution was requested from the treating physicians. Results: Until May 2009, 1,086 patients from 62 centers were recruited, including 404 patients (median age, 10.9 years) who had received radiotherapy to the thyroid gland and/or hypophysis. Follow-up information was available for 264 patients (60.9%; median follow-up, 40 months), with 60 patients (22.7%) showing pathologic values. In comparison to patients treated with prophylactic cranial irradiation (median dose, 12 Gy), patients with radiation doses of 15 to 25 Gy to the thyroid gland had a hazard ratio of 3.072 (p = 0.002) for the development of pathologic thyroid blood values. Patients with greater than 25 Gy to the thyroid gland and patients who underwent craniospinal irradiation had hazard ratios of 3.768 (p = 0.009) and 5.674 (p < 0.001), respectively. The cumulative incidence of thyroid hormone substitution therapy did not differ between defined subgroups. Conclusions: Radiation-induced thyroid function impairment, including damage to the thyroid gland and/or hypophysis, can frequently be observed after radiotherapy in children. A structured follow-up examination is advised.

  11. Pre-Radiotherapy dental evaluation criteria and treatment needs of oral side effects after head and neck radiotherapy

    International Nuclear Information System (INIS)

    Gonzalez-Arriagada, Wilfredo Alejandro; Santos-Silva, Alan Roger; Carvalho de Andrade, Marco Aurelio; De Andrade Elias, Rogerio; Ajudarte Lopes, Marcio

    2010-01-01

    The objective of this review is to present pre-radiotherapy evaluation criteria and the main needs for treatment of these patients after the radiation therapy. Were revised articles in English, Spanish and Portuguese language between 1995 and 2009 indexed in Pubmed and Scielo. The keywords were oral cancer and radiotherapy, complications in head and neck radiotherapy, oral pre-radiotherapy evaluation.The adverse complications of radiotherapy in head and neck area could be temporary or late. The late effects, such as radiation caries and osteorradionecrosis could be directly associated with the fact that previous dental evaluation was not performed and can severely affect the post-operatory quality of life. The participation of the dentist in the multidisciplinary team and dental evaluation of the patients that will receive radiotherapy in the head and neck area are of vital importance to improve the post-operatory quality of life of these patients

  12. The effect of radiotherapy, and radiotherapy combined with bisphosphonates or RANK ligand inhibitors on bone quality in bone metastases. A systematic review

    NARCIS (Netherlands)

    Groenen, K.H.J.; Pouw, M.H.; Hannink, G.; Hosman, A.J.; van der Linden, Y.M.; Verdonschot, Nicolaas Jacobus Joseph; Tanck, E.

    2016-01-01

    Purpose The role of radiotherapy in stabilizing metastatic bones is unclear. This systematic review assessed the effects of (1) radiotherapy, (2) radiotherapy combined with bisphosphonates, and (3) radiotherapy combined with RANK ligand (RANKL) inhibitors on bone quality and bone strength in bone

  13. Treatment plan evaluation using dose-volume histogram (DVH) and spatial dose-volume histogram (zDVH)

    International Nuclear Information System (INIS)

    Cheng, C.-W.; Das, Indra J.

    1999-01-01

    Objective: The dose-volume histogram (DVH) has been accepted as a tool for treatment-plan evaluation. However, DVH lacks spatial information. A new concept, the z-dependent dose-volume histogram (zDVH), is presented as a supplement to the DVH in three-dimensional (3D) treatment planning to provide the spatial variation, as well as the size and magnitude of the different dose regions within a region of interest. Materials and Methods: Three-dimensional dose calculations were carried out with various plans for three disease sites: lung, breast, and prostate. DVHs were calculated for the entire volume. A zDVH is defined as a differential dose-volume histogram with respect to a computed tomographic (CT) slice position. In this study, zDVHs were calculated for each CT slice in the treatment field. DVHs and zDVHs were compared. Results: In the irradiation of lung, DVH calculation indicated that the treatment plan satisfied the dose-volume constraint placed on the lung and zDVH of the lung revealed that a sizable fraction of the lung centered about the central axis (CAX) received a significant dose, a situation that warranted a modification of the treatment plan due to the removal of one lung. In the irradiation of breast with tangential fields, the DVH showed that about 7% of the breast volume received at least 110% of the prescribed dose (PD) and about 11% of the breast received less than 98% PD. However, the zDVHs of the breast volume in each of seven planes showed the existence of high-dose regions of 34% and 15%, respectively, of the volume in the two caudal-most planes and cold spots of about 40% in the two cephalic planes. In the treatment planning of prostate, DVHs showed that about 15% of the bladder and 40% of the rectum received 102% PD, whereas about 30% of the bladder and 50% of the rectum received the full dose. Taking into account the hollow structure of both the bladder and the rectum, the dose-surface histograms (DSH) showed larger hot-spot volume, about

  14. Item 141 Radiotherapy. Radiobiological notions; main secondary effects

    International Nuclear Information System (INIS)

    Azria, David; Dubois, Jean-Bernard

    2006-11-01

    This document first gives definitions of ionizing radiations, photons, electrons and Gray (as a dose unit). It describes the mechanisms of action of ionizing radiations: physical, chemical, cellular actions, actions on tissues. It analyses and discusses the factors influencing the effects of radiations: intrinsic radio-sensitivity, cellular cycle, oxygen, time (session fractioning and organisation in time), and dose. The different types of radiotherapy are then presented: external radiotherapy, brachytherapy, radio-immunotherapy of internal radiotherapy. It discusses tissues tolerance doses and doses required to sterilize tumours, and discusses the various and main secondary effects: stochastic secondary effects and deterministic secondary effects. A table indicates possible early and late reactions for different organs (skin, lung, brain, medulla, nerves, oesophagus, heart, pancreas, stomach, liver, intestine, kidney, bladder, rectum, ENT, or eye's lens)

  15. Side effects of curative radiotherapy of the prostatic cancer

    International Nuclear Information System (INIS)

    Ziegler, F.; Metzger, H.; Huebener, K.H.; Kurtz, B.

    1984-01-01

    The side effects of primary percutaneous radiotherapy in 100 patients with prostatic cancer were evaluated and classified into different degrees of gravity. It was shown that especially chronic side effects are benign in most of all cases. Severe - but not vitally dangerous - complications in bladder and intestine are rare (3%); their percentage corresponds roughly to the average mortality rate of surgical intervention (radical prostatectomy). Contrary to operation, troubles of the sexual function appear only in one third of the patients. Taking into consideration the similar therapeutic results of intervention and radiotherapy, radiotherapy is more favorable with respect to side effects. This essential aspects should be considered when making a decision whether to apply a surgical or radiotherapeutic treatment. (orig.) [de

  16. Dose volume relationships for intraoperatively irradiated saphenous nerve

    International Nuclear Information System (INIS)

    Gillette, E.L.; Powers, B.E.; Gillette, S.M.; Thames, H.D.; Childs, G.; Vujaskovic, Z.; LaRue, S.M.

    1995-01-01

    Purpose/Objective: Intraoperative radiation therapy (IORT) is used to deliver high single doses of radiation to the tumor bed following surgical removal of various abdominal malignancies. The advantage of IORT is the ability to remove sensitive normal tissues from the treatment field and to limit the volume of normal tissue irradiated. The purpose of this study was to determine dose-volume relationships for retroperitoneal tissues. Materials and methods: 134 adult beagle dogs were irradiated to the surgically exposed paraaortic area. Normal tissues included in the treatment field were aorta, peripheral nerve, ureter, bone and muscle. Groups of 4 - 8 dogs were irradiated to doses ranging from 18 - 54 Gy for a 2x5 cm field, from 12 - 46 Gy for a 4x5 cm field, and 12 - 42 Gy to an 8x5 cm field. The radiations were done using 6 MeV electrons from a linear accelerator. Dogs were observed for three years after radiation. Electrophysiologic procedures were done prior to irradiation and annually following irradiation. The procedures included electromyography of the pelvic limb and paralumbar muscles supplied by the L1 to S1 spinal nerves to determine presence and degree of motor unit disease. Motor nerve conduction velocities of the proximal and distal sciatic nerves were determined. Sensory nerve conduction velocities of the saphenous nerve were also determined. Evoked lumbosacral and thoraco-lumbar spinal cord potentials were evaluated following stimulation of the left sciatic nerve. In addition to electrophysiologic studies, neurologic examinations were done prior to treatment and at six month intervals for the three year observation period. At the three year time period, dogs were euthanatized, sections of peripheral nerve taken, routinely processed, stained with Masson's trichrome and evaluated histomorphometrically using point count techniques. Results: Twenty-two dogs were euthanatized prior to the three year observation period due to peripheral nerve damage

  17. Long-term effects of megavoltage radiotherapy in acromegaly

    International Nuclear Information System (INIS)

    Lam, K.S.L.; Wang, C.; Ma, J.T.C.; Yeung, R.T.T.; Choi, P.

    1989-01-01

    The progress of 41 Chinese patients with acromegaly treated with megavoltage radiotherapy was reviewed after a mean follow-up of 4.5 (one-ten) years. Nine received prior surgery. Radiotherapy was delivered by a 3-field technique to a total of 4000-5000 cGy in 25 fractions. By life table analysis successful treatment of growth hormone (GH) hypersecretion, as defined by a mean GH concentration of ≤ 10 mu/L, could be expected in 6, 11, 26, 64 and 67% of the patients after one, two, five, eight and ten years respectively. Median intervals before achieving a mean GH level of ≤ 10 Mu/L were 6.6 and 8.6 years following radiotherapy with the higher (4500-5000 cGy) and lower (4000 cGy) doses respectively, suggesting a tendency towards earlier response following radiotherapy with the higher dose. The prevalence of acquired hypopituitarism in patients followed up for over five years was 40% for gonadotrophins, 30% for TSH and 20% for ACTH deficiency respectively. In the majority of patients, acquired hypopituitarism was not apparent within five years after radiotherapy. No mortality or major side effects were noted following radiotherapy. In 34 patients on longterm bromocriptine treatment, mean GH concentrations were normalised in 26.5% of patients. We conclude that with judicious selection of patients and use of adjunctive medical therapy, megavoltage radiotherapy remains a safe and satisfactory form of treatment for acromegaly especially if expert transphenoidal surgery is not readily available. 19 refs., 3 figs., 2 tabs

  18. Effects of protoporphyrin disodium (Prolmon tablets) during radiotherapy

    International Nuclear Information System (INIS)

    Iwata, Takeo; Fukutomi, Toshio

    1981-01-01

    Effects of Prolmon tablets (medicine for hepatitis) on radiation syndrome (fatigue, nausea, vomiting, etc) which appeared during an early stage of radiotherapy were studied. Two tablets of Prolmon were administered to 10 patients with various tumors three times a day with concurrent use of other medicines during radiotherapy. A marked change in GOT and GPT values did not found, and the treatment was completed without any radiation syndrome in all patients. It was suggested that the administration of Prolmon tablets together with nutrients and vitamine preparations was effective to prevent radiation syndrome. (Tsunoda, M.)

  19. 7-Tesla Susceptibility-Weighted Imaging to Assess the Effects of Radiotherapy on Normal-Appearing Brain in Patients With Glioma

    International Nuclear Information System (INIS)

    Lupo, Janine M.; Chuang, Cynthia F.; Chang, Susan M.; Barani, Igor J.; Jimenez, Bert; Hess, Christopher P.; Nelson, Sarah J.

    2012-01-01

    Purpose: To evaluate the intermediate- and long-term imaging manifestations of radiotherapy on normal-appearing brain tissue in patients with treated gliomas using 7T susceptibility-weighted imaging (SWI). Methods and Materials: SWI was performed on 25 patients with stable gliomas on a 7 Tesla magnet. Microbleeds were identified as discrete foci of susceptibility that did not correspond to vessels. The number of microbleeds was counted within and outside of the T2-hyperintense lesion. For 3 patients, radiation dosimetry maps were reconstructed and fused with the 7T SWI data. Results: Multiple foci of susceptibility consistent with microhemorrhages were observed in patients 2 years after chemoradiation. These lesions were not present in patients who were not irradiated. The prevalence of microhemorrhages increased with the time since completion of radiotherapy, and these lesions often extended outside the boundaries of the initial high-dose volume and into the contralateral hemisphere. Conclusions: High-field SWI has potential for visualizing the appearance of microbleeds associated with long-term effects of radiotherapy on brain tissue. The ability to visualize these lesions in normal-appearing brain tissue may be important in further understanding the utility of this treatment in patients with longer survival.

  20. Effects of radiotherapy on the sense of taste

    Energy Technology Data Exchange (ETDEWEB)

    Umeyama, Masayoshi; Suzaki, Harumi [Showa Univ., Tokyo (Japan). School of Medicine

    2001-07-01

    The adverse effects of radiotherapy for cancer in the head and neck region include impairment of the sense of taste and smell and dry mouth. The present study was conducted to examine the effects of such radiotherapy on the sense of taste, in view of its influence on the quality of life of patients with malignant tumors of the head and neck following treatment. In 18 patients with malignant tumors of the head and neck (mean age, 59.9 years) the sense of taste was tested using the filter-paper disc method, serially before and after radiotherapy with {sup 60}Co {gamma} rays, in order to analyze the changes in gustatory threshold after radiotherapy. The patients were also observed for subjective symptoms, including dry mouth and impairment of the sense of taste, and changes in the lingual surface over the course of radiotherapy. No increase in the gustatory threshold or subjective impairment of the sense of taste was noted after radiotherapy when the field of irradiation did not include the tongue (4 cases of laryngeal cancer). When the field of irradiation included a part of the tongue (3 cases of maxillary cancer, 3 cases of hypopharyngeal cancer, 1 case of epipharyngeal cancer) or the entire tongue (2 cases of lingual cancer, 2 cases of cancer of the floor of the mouth, 3 cases of mesopharyngeal cancer), dry mouth was noted after irradiation at 7.2-39.6 Gy, and the gustatory threshold increased after irradiation at 12-40 Gy. Subjective impairment of the sense of taste was also reported after irradiation at 10-25.2 Gy, which was restored to normal within 2-3 months after the end of radiotherapy. In relation to the quality of taste, the gustatory threshold for sweet tastes increased the slowest, and was restored rapidly. In contrast, the gustatory threshold for sour tastes increased most rapidly, and was restored slowly. The relationship between the serum zinc level and the increase in gustatory threshold was unclear. There was a tendency for the lingual surface to

  1. Effects of radiotherapy on the sense of taste

    International Nuclear Information System (INIS)

    Umeyama, Masayoshi; Suzaki, Harumi

    2001-01-01

    The adverse effects of radiotherapy for cancer in the head and neck region include impairment of the sense of taste and smell and dry mouth. The present study was conducted to examine the effects of such radiotherapy on the sense of taste, in view of its influence on the quality of life of patients with malignant tumors of the head and neck following treatment. In 18 patients with malignant tumors of the head and neck (mean age, 59.9 years) the sense of taste was tested using the filter-paper disc method, serially before and after radiotherapy with 60 Co γ rays, in order to analyze the changes in gustatory threshold after radiotherapy. The patients were also observed for subjective symptoms, including dry mouth and impairment of the sense of taste, and changes in the lingual surface over the course of radiotherapy. No increase in the gustatory threshold or subjective impairment of the sense of taste was noted after radiotherapy when the field of irradiation did not include the tongue (4 cases of laryngeal cancer). When the field of irradiation included a part of the tongue (3 cases of maxillary cancer, 3 cases of hypopharyngeal cancer, 1 case of epipharyngeal cancer) or the entire tongue (2 cases of lingual cancer, 2 cases of cancer of the floor of the mouth, 3 cases of mesopharyngeal cancer), dry mouth was noted after irradiation at 7.2-39.6 Gy, and the gustatory threshold increased after irradiation at 12-40 Gy. Subjective impairment of the sense of taste was also reported after irradiation at 10-25.2 Gy, which was restored to normal within 2-3 months after the end of radiotherapy. In relation to the quality of taste, the gustatory threshold for sweet tastes increased the slowest, and was restored rapidly. In contrast, the gustatory threshold for sour tastes increased most rapidly, and was restored slowly. The relationship between the serum zinc level and the increase in gustatory threshold was unclear. There was a tendency for the lingual surface to become dry

  2. Effect of radiotherapy on lymphocyte populations in lung cancer

    International Nuclear Information System (INIS)

    Gava, A.; Coghetto, F.; Marazzato, G.; Fantin, P.L.; Patrese, P.; Moro, L.; De Angeli, S.

    1988-01-01

    The authors report on the results of the immune monitoring of a study population of 31 patients with lung cancer who were treated with radiotherapy. Asynthetic thymic pentapeptide, Thymopentin, was employed-whose effect was evaluated on the immunological parameters analyzed. After radiotherapy, a considerable and homogeneous decrement was observed in several lymphocytic subset (less sensible in activated T-cells), together with a progressive decrement in the helper/suppressor ratio, in the long run. Monocytes and null cells showed more radioresistance. Thymopentin had no influence on the tested immunological parameters up tp 6 months after radiotherapy; later on, a slightly more balanced helper/suppressor ratio could be noticed in the surviving patients who had benn treated with Thymopentin

  3. [Effects of radiotherapy on lymphocyte populations in lung cancer].

    Science.gov (United States)

    Gava, A; Moro, L; De Angeli, S; Coghetto, F; Marazzato, G; Fantin, P; Patrese, P

    1988-11-01

    The authors report on the results of the immune monitoring of a study population of 31 patients with lung cancer who were treated with radiotherapy. A synthetic thymic pentapeptide, thymopentin, was employed whose effect was evaluated on the immunological parameters analyzed. After radiotherapy, a considerable and homogeneous decrement was observed in several lymphocytic subsets (less sensible in activated T-cells), together with a progressive decrement in the helper/suppressor ratio, in the long run. Monocytes and null cells showed more radioresistance. Thymopentin had no influence on the tested immunological parameters up to 6 months after radiotherapy; later on, a slightly more balanced helper/suppressor ratio could be noticed in the surviving patients who had been treated with thymopentin.

  4. Cost-effectiveness of surgery plus radiotherapy versus radiotherapy alone for metastatic epidural spinal cord compression

    International Nuclear Information System (INIS)

    Thomas, Kenneth C.; Nosyk, Bohdan; Fisher, Charles G.; Dvorak, Marcel; Patchell, Roy A.; Regine, William F.; Loblaw, Andrew; Bansback, Nick; Guh, Daphne; Sun, Huiying; Anis, Aslam

    2006-01-01

    Purpose: A recent randomized clinical trial has demonstrated that direct decompressive surgery plus radiotherapy was superior to radiotherapy alone for the treatment of metastatic epidural spinal cord compression. The current study compared the cost-effectiveness of the two approaches. Methods and Materials: In the original clinical trial, clinical effectiveness was measured by ambulation and survival time until death. In this study, an incremental cost-effectiveness analysis was performed from a societal perspective. Costs related to treatment and posttreatment care were estimated and extended to the lifetime of the cohort. Weibull regression was applied to extrapolate outcomes in the presence of censored clinical effectiveness data. Results: From a societal perspective, the baseline incremental cost-effectiveness ratio (ICER) was found to be $60 per additional day of ambulation (all costs in 2003 Canadian dollars). Using probabilistic sensitivity analysis, 50% of all generated ICERs were lower than $57, and 95% were lower than $242 per additional day of ambulation. This analysis had a 95% CI of -$72.74 to 309.44, meaning that this intervention ranged from a financial savings of $72.74 to a cost of $309.44 per additional day of ambulation. Using survival as the measure of effectiveness resulted in an ICER of $30,940 per life-year gained. Conclusions: We found strong evidence that treatment of metastatic epidural spinal cord compression with surgery in addition to radiotherapy is cost-effective both in terms of cost per additional day of ambulation, and cost per life-year gained

  5. Adverse effects of radiotherapy on the central nervous system

    International Nuclear Information System (INIS)

    Mocquard, Y.; Marion, J.L.; Goas, J.Y.

    1985-01-01

    Adverse effects of radiotherapy on the central nervous system are increasingly met with. Both the brain and spinal cord may be involved. Whereas some forms have a favorable outcome, many run a relentlessly progressive course, failing to respond to treatment. Improvement of radiation protocols should achieve a lower complication rate [fr

  6. Pilot study in the treatment of endometrial carcinoma with 3D image-based high-dose-rate brachytherapy using modified Heyman packing: Clinical experience and dose-volume histogram analysis

    International Nuclear Information System (INIS)

    Weitmann, Hajo Dirk; Poetter, Richard; Waldhaeusl, Claudia; Nechvile, Elisabeth; Kirisits, Christian; Knocke, Tomas Hendrik

    2005-01-01

    Purpose: The aim of this study was to evaluate dose distribution within uterus (clinical target volume [CTV]) and tumor (gross tumor volume [GTV]) and the resulting clinical outcome based on systematic three-dimensional treatment planning with dose-volume adaptation. Dose-volume assessment and adaptation in organs at risk and its impact on side effects were investigated in parallel. Methods and Materials: Sixteen patients with either locally confined endometrial carcinoma (n = 15) or adenocarcinoma of uterus and ovaries after bilateral salpingo-oophorectomy (n = 1) were included. Heyman packing was performed with mean 11 Norman-Simon applicators (3-18). Three-dimensional treatment planning based on computed tomography (n = 29) or magnetic resonance imaging (n = 18) was done in all patients with contouring of CTV, GTV, and organs at risk. Dose-volume adaptation was achieved by dwell location and time variation (intensity modulation). Twelve patients treated with curative intent received five to seven fractions of high-dose-rate brachytherapy (7 Gy per fraction) corresponding to a total dose of 60 Gy (2 Gy per fraction and α/β of 10 Gy) to the CTV. Four patients had additional external beam radiotherapy (range, 10-40 Gy). One patient had salvage brachytherapy and 3 patients were treated with palliative intent. A dose-volume histogram analysis was performed in all patients. On average, 68% of the CTV and 92% of the GTV were encompassed by the 60 Gy reference volume. Median minimum dose to 90% of CTV and GTV (D90) was 35.3 Gy and 74 Gy, respectively. Results: All patients treated with curative intent had complete remission (12/12). After a median follow-up of 47 months, 5 patients are alive without tumor. Seven patients died without tumor from intercurrent disease after median 22 months. The patient with salvage treatment had a second local recurrence after 27 months and died of endometrial carcinoma after 57 months. In patients treated with palliative intent

  7. Dose Volume Histogram analysis for rectum and urethral reaction of prostate cancer

    International Nuclear Information System (INIS)

    Yanagi, Takeshi; Tsuji, Hiroshi; Kamada, Tadashi; Tsujii, Hirohiko

    2005-01-01

    The aim of this study is to evaluate the clinically relevant parameters for rectum and urethral reaction using DVH (dose volume histogram) in carbon ion radiotherapy of prostate cancer. In this year, we studied the urinary reaction mainly. 35 patients with prostate cancer were treated with carbon ion beams between June 1995 and December 1997. The applied dose was escalated from 54.0 GyE to 72.0 GyE in fixed 20 fractions. Clinical urinary reaction and rectum reaction were reviewed using Radiation Therapy Oncology Group (RTOG) scoring system for acute reactions, RTOG/European Organization for Research and Treatment of Cancer (EORTC) scoring system for late reactions. Taking the ROI (region of interest) for DVH of urethra, we used surrogate one that was derived from the observation of MR images. 35 patients were analyzed for acute urinary reaction and 34 for late urinary reaction in the study of this year. DVH analysis suggested difference among the grades for acute and late reactions. These analysis appears to be a useful tool for predicting the urinary reactions. (author)

  8. Dose-volume effect relationships for late rectal morbidity in patients treated with chemoradiation and MRI-guided adaptive brachytherapy for locally advanced cervical cancer: Results from the prospective multicenter EMBRACE study

    DEFF Research Database (Denmark)

    Mazeron, Renaud; Fokdal, Lars U; Kirchheiner, Kathrin

    2016-01-01

    Purpose To establish dose volume–effect relationships predicting late rectal morbidity in cervix cancer patients treated with concomitant chemoradiation and MRI-guided adaptive brachytherapy (IBABT) within the prospective EMBRACE study. Material and method All patients were treated with curative ...

  9. Proton Radiotherapy for Parameningeal Rhabdomyosarcoma: Clinical Outcomes and Late Effects

    Energy Technology Data Exchange (ETDEWEB)

    Childs, Stephanie K. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Kozak, Kevin R. [Department of Radiation Oncology, University of Wisconsin Cancer Center Johnson Creek, Madison, WI (United States); Friedmann, Alison M. [Department of Pediatric Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Yeap, Beow Y. [Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Adams, Judith; MacDonald, Shannon M.; Liebsch, Norbert J.; Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Yock, Torunn I., E-mail: tyock@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

    2012-02-01

    Purpose: To report the clinical outcome and late side effect profile of proton radiotherapy in the treatment of children with parameningeal rhabdomyosarcoma (PM-RMS). Methods and Materials: Seventeen consecutive children with PM-RMS were treated with proton radiotherapy at Massachusetts General Hospital between 1996 and 2005. We reviewed the medical records of all patients and asked referring physicians to report specific side effects of interest. Results: Median patient age at diagnosis was 3.4 years (range, 0.4-17.6). Embryonal (n = 11), alveolar (n = 4), and undifferentiated (n = 2) histologies were represented. Ten patients (59%) had intracranial extension. Median prescribed dose was 50.4 cobalt gray equivalents (GyRBE) (range, 50.4-56.0 GyRBE) delivered in 1.8-2.0-GyRBE daily fractions. Median follow-up was 5.0 years for survivors. The 5-year failure-free survival estimate was 59% (95% confidence interval, 33-79%), and overall survival estimate was 64% (95% confidence interval, 37-82%). Among the 7 patients who failed, sites of first recurrence were local only (n = 2), regional only (n = 2), distant only (n = 2), and local and distant (n = 1). Late effects related to proton radiotherapy in the 10 recurrence-free patients (median follow-up, 5 years) include failure to maintain height velocity (n = 3), endocrinopathies (n = 2), mild facial hypoplasia (n = 7), failure of permanent tooth eruption (n = 3), dental caries (n = 5), and chronic nasal/sinus congestion (n = 2). Conclusions: Proton radiotherapy for patients with PM-RMS yields tumor control and survival comparable to that in historical controls with similar poor prognostic factors. Furthermore, rates of late effects from proton radiotherapy compare favorably to published reports of photon-treated cohorts.

  10. Effects of hyperthermia, radiotherapy and thermoradiotherapy on tumor microvasculature

    International Nuclear Information System (INIS)

    Fujiwara, Kouji

    1987-01-01

    The therapeutic effects of hyperthermia (immersion of tumor-bearing leg in a water bath at 46 deg C for 60 min), radiotherapy (500 rad or 1000 rad) and thermoradiotherapy on VX-2 tumors of the rabbits were studied morphologically. Especially, vascular morphological changes and vascular permeability to ferritin after treatment were investigated by electron microscopy. As assessed by decrease in tumor volume, local hyperthermia potentiated the destructive effect of radiotherapy. The light microscopic pictures invariably suggested prolonged necrotic tendency of tumor cells following thermoradiotherapy. Electron microscopically, 1 day and 3 days after thermoradiotherapy, small blood vessels in the tumors showed swelling and protrusion of endothelial cells in the lumen. Similar morphological changes were obtained only at 3 days after radiotherapy. When vascular permeability to ferritin was examined by electron microscopy, an increase in tumor vascular permeability was occured at 1 day after hyperthermia or thermoradiotherapy, while at 3 days after radiotherapy. These results suggest that the early reaction of tumor microvasculature may be a contributing factor to delayed cell death in tumors after hyperthermia or thermoradiotherapy. (author)

  11. Effects of Aglumin on the rectal bleeding following radiotherapy

    International Nuclear Information System (INIS)

    Yamashita, Michitaka; Tanaka, Motoshi; Yoshimura, Osamu; Matsubayashi, Shigeru

    1978-01-01

    Aglumin was administered to 20 cases which had rectal bleeding following radiotherapy. The results were as follows. Rectal bleeding decreased in 16 of 20 cases (80%): remarkably effective, 15%; effective, 25%; slightly effective, 40%. Bleeding time decreased in 11 cases (55%). Rumpel-Leede test gave remarkable improvement in 10 of 14 cases which had been abnormal (71.4%). Platelet increased in 18 of 20 cases (90%). Liver function test and peripheral blood findings showed no remarkable changes. No side effects such as intestinal disturbance etc were noted. In the series of symptomatic treatment for rectal disturbance resulting from radiotherapy, this drug had considerable effect of hemostasis. It was concluded that this drug is useful in combined use with other antiphlogistics, analgesic, and hematinic etc. (Ueda, J.)

  12. A model to incorporate organ deformation in the evaluation of dose/volume relationship

    International Nuclear Information System (INIS)

    Yan, D.; Jaffray, D.; Wong, J.; Brabbins, D.; Martinez, A. A.

    1997-01-01

    Purpose: Measurements of internal organ motion have demonstrated that daily organ deformation exists during the course of radiation treatment. However, a model to evaluate the resultant dose delivered to a daily deformed organ remains a difficult challenge. Current methods which model such organ deformation as rigid body motion in the dose calculation for treatment planning evaluation are incorrect and misleading. In this study, a new model for treatment planning evaluation is introduced which incorporates patient specific information of daily organ deformation and setup variation. The model was also used to retrospectively analyze the actual treatment data measured using daily CT scans for 5 patients with prostate treatment. Methods and Materials: The model assumes that for each patient, the organ of interest can be measured during the first few treatment days. First, the volume of each organ is delineated from each of the daily measurements and cumulated in a 3D bit-map. A tissue occupancy distribution is then constructed with the 50% isodensity representing the mean, or effective, organ volume. During the course of treatment, each voxel in the effective organ volume is assumed to move inside a local 3D neighborhood with a specific distribution function. The neighborhood and the distribution function are deduced from the positions and shapes of the organ in the first few measurements using the biomechanics model of viscoelastic body. For each voxel, the local distribution function is then convolved with the spatial dose distribution. The latter includes also the variation in dose due to daily setup error. As a result, the cumulative dose to the voxel incorporates the effects of daily setup variation and organ deformation. A ''variation adjusted'' dose volume histogram, aDVH, for the effective organ volume can then be constructed for the purpose of treatment evaluation and optimization. Up to 20 daily CT scans and daily portal images for 5 patients with prostate

  13. Actinic cell effects after radiotherapy for cervical cancer

    International Nuclear Information System (INIS)

    Padilha, C.M.L.; Bergmann, A.; Chaves, C.B.P.; Thuler, L.C.S.; Araújo Junior, M.L.C.; Souza, S.A.L. de

    2017-01-01

    Introduction: It is very common for patients with cervical cancer to be referred to the radiotherapy when the disease is in advanced stages, this fact determines high rates of locoregional recurrence. Radiation treatment causes actinic morphological changes, not only in neoplastic epithelial cells, but also in normal cells. These changes induced by radiation, often make difficult the differential diagnosis of the residual lesion, resulting in a dilemma in cytopathological follow-up. Objective: To describe the actinic cytopathologic changes in patients submitted to radiotherapy for cervical cancer. Methodology: The re-evaluation of cytopathologic smears and description of actinic cytopathic effects were performed. This information was complemented by the cytopathological report of the smears, available in the archives of the Division of Pathology (DIPAT) / INCA. Results: The most frequent cytopathological changes observed were: nuclear activation, cytoplasmic enhancement, cytoplasmic vacuolisation, eosinophilia, polychromasia, multinucleated giant cells, binucleation, nuclear vacuolisation, prominent nucleoli, as well as presence of leukocyte exudate. Conclusion: The cytopathological diagnosis of tumor persistence or recurrence after radiotherapy is always a great challenge for the professional, even the experienced one. Studies and reports in the literature on actinic cytopathologic changes and radiotherapy are scarce

  14. A theoretical approach to the problem of dose-volume constraint estimation and their impact on the dose-volume histogram selection

    International Nuclear Information System (INIS)

    Schinkel, Colleen; Stavrev, Pavel; Stavreva, Nadia; Fallone, B. Gino

    2006-01-01

    This paper outlines a theoretical approach to the problem of estimating and choosing dose-volume constraints. Following this approach, a method of choosing dose-volume constraints based on biological criteria is proposed. This method is called ''reverse normal tissue complication probability (NTCP) mapping into dose-volume space'' and may be used as a general guidance to the problem of dose-volume constraint estimation. Dose-volume histograms (DVHs) are randomly simulated, and those resulting in clinically acceptable levels of complication, such as NTCP of 5±0.5%, are selected and averaged producing a mean DVH that is proven to result in the same level of NTCP. The points from the averaged DVH are proposed to serve as physical dose-volume constraints. The population-based critical volume and Lyman NTCP models with parameter sets taken from literature sources were used for the NTCP estimation. The impact of the prescribed value of the maximum dose to the organ, D max , on the averaged DVH and the dose-volume constraint points is investigated. Constraint points for 16 organs are calculated. The impact of the number of constraints to be fulfilled based on the likelihood that a DVH satisfying them will result in an acceptable NTCP is also investigated. It is theoretically proven that the radiation treatment optimization based on physical objective functions can sufficiently well restrict the dose to the organs at risk, resulting in sufficiently low NTCP values through the employment of several appropriate dose-volume constraints. At the same time, the pure physical approach to optimization is self-restrictive due to the preassignment of acceptable NTCP levels thus excluding possible better solutions to the problem

  15. Prognosis after acute lymphoblastic leukaemia. [Side effects of radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, C B

    1975-04-01

    Following chemotherapy of lymphoblastic leukemia in children with folic acid antagonists, remission is achieved in 94 percent of patients. After chemotherapy has been stopped the risk of relapse is greatest during the first year, but relapses do occur. Sequelae of radiotherapy include bone growth impairment, brain cell damage, radioinduced neoplasms, and immunosuppression. Adverse effects of chemotherapy include hepatic fibrosis, impaired gonadal development, and oncogenic effects. (HLW)

  16. The effect on the radiotherapy for cervical cancer patients quality of life and the related health education

    International Nuclear Information System (INIS)

    Gao Xinli

    2012-01-01

    Radiotherapy is an important means of cervical cancer, due to the specificity of tumor site and side effect of radiotherapy, lack of knowledge of radiotherapy for patients and relatives about the disease, It is particularly important during radiotherapy on health education. By the analysis of radiotherapy for cervical cancer patients quality of life, it is the purpose of patients during the period of radiotherapy of whole course health education. Including before radiotherapy, radiotherapy in health education and the guide of the leaving hospital. In order to improve the compliance of patients, reduce the complications. Further it is improved the clinical treatment effect. (author)

  17. Effects of radiotherapy in the treatment of multiple myeloma

    International Nuclear Information System (INIS)

    Ochtrop, Thomas Alexander

    2015-01-01

    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. Patients and methods: 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 and 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). Results: 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. Conclusions: Higher total biological radiation doses were associated with better pain

  18. The potential effectiveness of nanoparticles as radio sensitizers for radiotherapy

    Directory of Open Access Journals (Sweden)

    Mohammad Babaei

    2014-03-01

    Full Text Available Introduction: Application of nanoparticles as radio sensitizer is a promising field to improve efficiency of radiotherapy.Methods:This study was conducted to review nano radio sensitizers. PubMed, Ovid Medline, Science Direct, Scopus, ISI web of knowledge, and Springer databases were searched from 2000 to May 2013 to identify relevant studies. Search was restricted to English language. Results: We included any study that evaluated nanoparticles, volunteer of radio enhancement at radiotherapy on animals or cell lines. Nanoparticles can increase radio sensitivity of tumor cells. This effect was shown in vivo and in vitro, at kilovltage or megavoltage energies, in 24 reviewed studies. Focus of studies was on gold nanoparticles. Radio sensitizing effects of nanoparticles depend on nanoparticles’ size, type, concentration, intracellular localization, used irradiation energy and tested cell line.Conclusion: Literature suggests potency of nanoparticles for increasing cell radio sensitivity. Reviewed results are promising and warrant future clinical trials.

  19. Effects of orbital radiotherapy in 199 cases of Graves' ophthalmopathy

    International Nuclear Information System (INIS)

    Beckendorf, Veronique; Bey, Pierre; George, Jean Louis; Maalouf, Toufic; Leclere, Jacques; Werhya, Gerard; Luporsi, Elisabeth

    1997-01-01

    Purpose/Objective: Retrospective study to assess response of Graves' orbitopathy to standardized retrobulbar radiotherapy. Effects on different classes of signs are analysed and prognostic factors are searched. Indications of this treatment can be precise. Materials and methods: One hundred and ninety-nine consecutive patients who had clinically progressive Graves'orbitopathy were treated with radiotherapy between 1977 and 1996. All patients received a 6 MV Xrays orbital irradiation of 20 Gy in 10 fractions and 2 weeks. Signs and symptoms were classified before and after treatment directly or retrospectively according to the 'NO SPECS' recommended classification [J Clin Endocrinol Metab 1977;44:203]. Index of ophthalmopathy and responses were evaluated as described by Donaldson [J Clin Endocrinol Metab 1973;37:276]. Prognostic factors such as age, gender, therapies and response of hyperthyroidism, duration and associated treatment of eye disease are analysed. An investigation through letters sent to the patients and their ophthalmologists documents long term outcome of 128 patients with a mean follow-up of 6 years (2 to 16 years). Results: On 195 evaluable patients, 50 (26%) achieved a good or excellent response -GER-, 98 (50 %) had slight improvement, 37 (19 %) were stable, 10 (5 %) had progression of Grave's ophthalmopathy. By class of signs, GER occurred in 37%, 34%, 38%, 37.5% of cases, respectively for soft tissues involvement, proptosis, extra ocular muscle involvement and optic neuropathy. Corneal involvements yields the best results with 49% GER. Proptosis when moderate form had good results (55% GER), but advanced presentations had poor responses (17% GER). Proptosis decreased of 1 to 3 mm or remained stable. Six patients treated for optic neuropathy experienced aggravation. Same efficacy was observed when radiotherapy was applied as first line therapy or after failure of corticosteroids and when radiotherapy was delayed up to one year after beginning of

  20. Comments on 'Reconsidering the definition of a dose-volume histogram'-dose-mass histogram (DMH) versus dose-volume histogram (DVH) for predicting radiation-induced pneumonitis

    International Nuclear Information System (INIS)

    Mavroidis, Panayiotis; Plataniotis, Georgios A; Gorka, Magdalena Adamus; Lind, Bengt K

    2006-01-01

    In a recently published paper (Nioutsikou et al 2005 Phys. Med. Biol. 50 L17) the authors showed that the use of the dose-mass histogram (DMH) concept is a more accurate descriptor of the dose delivered to lung than the traditionally used dose-volume histogram (DVH) concept. Furthermore, they state that if a functional imaging modality could also be registered to the anatomical imaging modality providing a functional weighting across the organ (functional mass) then the more general and realistic concept of the dose-functioning mass histogram (D[F]MH) could be an even more appropriate descriptor. The comments of the present letter to the editor are in line with the basic arguments of that work since their general conclusions appear to be supported by the comparison of the DMH and DVH concepts using radiobiological measures. In this study, it is examined whether the dose-mass histogram (DMH) concept deviated significantly from the widely used dose-volume histogram (DVH) concept regarding the expected lung complications and if there are clinical indications supporting these results. The problem was investigated theoretically by applying two hypothetical dose distributions (Gaussian and semi-Gaussian shaped) on two lungs of uniform and varying densities. The influence of the deviation between DVHs and DMHs on the treatment outcome was estimated by using the relative seriality and LKB models using the Gagliardi et al (2000 Int. J. Radiat. Oncol. Biol. Phys. 46 373) and Seppenwoolde et al (2003 Int. J. Radiat. Oncol. Biol. Phys. 55 724) parameter sets for radiation pneumonitis, respectively. Furthermore, the biological equivalent of their difference was estimated by the biologically effective uniform dose (D-bar) and equivalent uniform dose (EUD) concepts, respectively. It is shown that the relation between the DVHs and DMHs varies depending on the underlying cell density distribution and the applied dose distribution. However, the range of their deviation in terms of

  1. Radiotherapy physics

    International Nuclear Information System (INIS)

    Chen, G.T.Y.; Collier, J.M.; Lyman, J.T.; Pitluck, S.

    1982-01-01

    The Radiotherapy Physics Group works on the physical and biophysical aspects of charged particle radiotherapy. Our activities include the development of isosurvival beams (beams of uniform biological effect), computerized treatment planning development for charged particle radiotherapy, design of compensation to shape dose distributions, and development of dosimetry techniques to verify planned irradiations in both phantoms and patients

  2. Non-Targeted effects of ionising radiation and radiotherapy

    International Nuclear Information System (INIS)

    Sjostedt, Svetlana; Bezak, Eva

    2010-01-01

    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.

  3. Stereotactic intracranial radiotherapy: Dose prescription

    International Nuclear Information System (INIS)

    Schlienger, M.; Lartigau, E.; Nataf, F.; Mornex, F.; Latorzeff, I.; Lisbona, A.; Mahe, M.

    2012-01-01

    The aim of this article was the study of the successive steps permitting the prescription of dose in stereotactic intracranial radiotherapy, which includes radiosurgery and fractionated stereotactic radiotherapy. The successive steps studied are: the choice of stereotactic intracranial radiotherapy among the therapeutic options, based on curative or palliative treatment intent, then the selection of lesions according to size/volume, pathological type and their number permitting the choice between radiosurgery or fractionated stereotactic radiotherapy, which have the same methodological basis. Clinical experience has determined the level of dose to treat the lesions and limit the irradiation of healthy adjacent tissues and organs at risk structures. The last step is the optimization of the different parameters to obtain a safe compromise between the lesion dose and healthy adjacent structures. Study of dose-volume histograms, coverage indices and 3D imaging permit the optimization of irradiation. For lesions close to or included in a critical area, the prescribed dose is planned using the inverse planing method. Implementation of the successively described steps is mandatory to insure the prescription of an optimized dose. The whole procedure is based on the delineation of the lesion and adjacent healthy tissues. There are sometimes difficulties to assess the delineation and the volume of the target, however improvement of local control rates and reduction of secondary effects are the proof that the totality of the successive procedures are progressively improved. In practice, stereotactic intracranial radiotherapy is a continually improved treatment method, which constantly benefits from improvements in the choice of indications, imaging, techniques of irradiation, planing/optimization methodology and irradiation technique and from data collected from prolonged follow-up. (authors)

  4. Effects of radiotherapy on anti-cancer immune response: mathematical modeling

    International Nuclear Information System (INIS)

    Isaeva, O.G.; Osipov, V.A.

    2009-01-01

    The influence of radiotherapy on the tumor-immune dynamics is studied within our recent model. Simulation of the standard course of radiotherapy shows that in the case of weak immune response a few months after cure the tumor achieves the maximum size, whereas the strong immune system is able to handle the growth of survived tumor cells population. Simulation of vaccine therapy after radiotherapy has been carried out. The high efficiency of vaccination is found provided that it is assigned during a certain period of time after radiotherapy. Different strategies of radiotherapy have been considered. It is shown that hyper rectification is more effective for treatment in comparison with other cures

  5. On the clinical effect of Pantocin in radiotherapy

    International Nuclear Information System (INIS)

    Natsume, Hiroshi; Obata, Koji; Honda, Yasuaki; Murase, Tatsuyoshi

    1975-01-01

    5-fold powder (3g/day) of Pantocin was given orally to 11 patients with urologic malignant tumor for the prevention of side effects following telecobalt irradiation. The blood test was performed approximately weekly (red blood cell count, hemoglobin, hematocrit, white blood cell count, platelet count). Mild radiation sickness was observed in 6 of the 11 cases, but in no case, continuation of irradiation was impossible. No side effect attributable to the oral administration of Pantocin was observed. Pantocin is thought to be an effective drug for alleviation of radiation sickness as well as for the prevention or treatment of hematological properties in radiotherapy. (Chiba, N.)

  6. The effects of radiotherapy and surgery on the sexual function of women treated for cervical cancer

    International Nuclear Information System (INIS)

    Flay, Linda D.; Matthews, John H.L.

    1995-01-01

    Purpose: This study investigated the short- and medium-term effects of pelvic radiotherapy and surgery on the sexual function of women treated for cervical cancer. Methods and Materials: Sixteen women with Stages I, II, or III disease referred for radiotherapy treatment were assessed. Six had undergone prior hysterectomy. The women were assessed with questionnaires prior to radiotherapy, at completion of radiotherapy, and at 6 weeks and 14 weeks after radiotherapy treatment. The clinical findings at routine follow-up were noted. Results: The study showed significant changes in sexual activity and satisfaction as a result of treatment. This was due to a number of physical and psychological factors. The level of sexual activity was lowest at completion of radiotherapy treatment. A feeling of vaginal shortening was the most frequent reason and was more common in women who were treated with surgery and radiotherapy. Dyspareunia, bleeding, and concern of bleeding and/or recurrence were all significant factors. Conclusions: The questionnaires were an effective way of assessing women's sexual function. Radiotherapy caused sexual dysfunction in one-half of women. Combined treatment with radiotherapy and surgery results in a higher risk than radiotherapy alone. Women with cervical cancer and undergoing radiotherapy treatment require considerable counseling and support

  7. Dose-Volume Histogram Analysis of the Safety of Proton Beam Therapy for Unresectable Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Kawashima, Mitsuhiko; Kohno, Ryosuke; Nakachi, Kohei; Nishio, Teiji; Mitsunaga, Shuichi; Ikeda, Masafumi; Konishi, Masaru; Takahashi, Shinichiro; Gotohda, Naoto; Arahira, Satoko; Zenda, Sadamoto; Ogino, Takashi; Kinoshita, Taira

    2011-01-01

    Purpose: To evaluate the safety and efficacy of radiotherapy using proton beam (PRT) for unresectable hepatocellular carcinoma. Methods and Materials: Sixty consecutive patients who underwent PRT between May 1999 and July 2007 were analyzed. There were 42 males and 18 females, with a median age of 70 years (48-92 years). All but 1 patient had a single lesion with a median diameter of 45 mm (20-100 mm). Total PRT dose/fractionation was 76-cobalt Gray equivalent (CGE)/20 fractions in 46 patients, 65 CGE/26 fractions in 11 patients, and 60 CGE/10 fractions in 3 patients. The risk of developing proton-induced hepatic insufficiency (PHI) was estimated using dose-volume histograms and an indocyanine-green retention rate at 15 minutes (ICG R15). Results: None of the 20 patients with ICG R15 of less than 20% developed PHI, whereas 6 of 8 patients with ICG R15 values of 50% or higher developed PHI. Among 32 patients whose ICG R15 ranged from 20% to 49.9%, PHI was observed only in patients who had received 30 CGE (V30) to more than 25% of the noncancerous parts of the liver (n = 5) Local progression-free and overall survival rates at 3 years were 90% (95% confidence interval [CI], 80-99%) and 56% (95% CI, 43-69%), respectively. A gastrointestinal toxicity of Grade ≥2 was observed in 3 patients. Conclusions: ICG R15 and V30 are recommended as useful predictors for the risk of developing PHI, which should be incorporated into multidisciplinary treatment plans for patients with this disease.

  8. Normal tissue complication probabilities correlated with late effects in the rectum after prostate conformal radiotherapy

    International Nuclear Information System (INIS)

    Dale, Einar; Olsen, Dag R.; Fossa, Sophie D.

    1999-01-01

    Purpose: Radiation therapy of deep-sited tumours will always result in normal tissue doses to some extent. The aim of this study was to calculate different risk estimates of late effects in the rectum for a group of cancer prostate patients treated with conformal radiation therapy (CRT) and correlate these estimates with the occurrences of late effects. Since the rectum is a hollow organ, several ways of generating dose-volume distributions over the organ are possible, and we wanted to investigate two of them. Methods and Materials: A mathematical model, known as the Lyman-Kutcher model, conventionally used to estimate normal tissue complication probabilities (NTCP) associated with radiation therapy, was applied to a material of 52 cancer prostate patients. The patients were treated with a four field box technique, with the rectum as organ at risk. Dose-volume histograms (DVH) were generated for the whole rectum (including the cavity) and of the rectum wall. One to two years after the treatment, the patients completed a questionnaire concerning bowel (rectum) related morbidity quantifying the extent of late effects. Results: A correlation analysis using Spearman's rank correlation coefficient, for NTCP values calculated from the DVHs and the patients' scores, gave correlation coefficients which were not statistically significant at the p max , of the whole rectum, correlated better to observed late toxicity than D max derived from histograms of the rectum wall. Correlation coefficients from 'high-dose' measures were larger than those calculated from the NTCP values. Accordingly, as the volume parameter of the Lyman-Kutcher model was reduced, raising the impact of small high-dose volumes on the NTCP values, the correlation between observed effects and NTCP values became significant at p < 0.01 level. Conclusions: 1) High-dose levels corresponding to small volume fractions of the cumulative dose-volume histograms were best correlated with the occurrences of late

  9. Motion induced interplay effects for VMAT radiotherapy.

    Science.gov (United States)

    Edvardsson, Anneli; Nordström, Fredrik; Ceberg, Crister; Ceberg, Sofie

    2018-04-19

    The purpose of this study was to develop a method to simulate breathing motion induced interplay effects for volumetric modulated arc therapy (VMAT), to verify the proposed method with measurements, and to use the method to investigate how interplay effects vary with different patient- and machine specific parameters. VMAT treatment plans were created on a virtual phantom in a treatment planning system (TPS). Interplay effects were simulated by dividing each plan into smaller sub-arcs using an in-house developed software and shifting the isocenter for each sub-arc to simulate a sin 6 breathing motion in the superior-inferior direction. The simulations were performed for both flattening-filter (FF) and flattening-filter free (FFF) plans and for different breathing amplitudes, period times, initial breathing phases, dose levels, plan complexities, CTV sizes, and collimator angles. The resulting sub-arcs were calculated in the TPS, generating a dose distribution including the effects of motion. The interplay effects were separated from dose blurring and the relative dose differences to 2% and 98% of the CTV volume (ΔD 98% and ΔD 2% ) were calculated. To verify the simulation method, measurements were carried out, both static and during motion, using a quasi-3D phantom and a motion platform. The results of the verification measurements during motion were comparable to the results of the static measurements. Considerable interplay effects were observed for individual fractions, with the minimum ΔD 98% and maximum ΔD 2% being  -16.7% and 16.2%, respectively. The extent of interplay effects was larger for FFF compared to FF and generally increased for higher breathing amplitudes, larger period times, lower dose levels, and more complex treatment plans. Also, the interplay effects varied considerably with the initial breathing phase, and larger variations were observed for smaller CTV sizes. In conclusion, a method to simulate motion induced interplay effects was

  10. Motion induced interplay effects for VMAT radiotherapy

    Science.gov (United States)

    Edvardsson, Anneli; Nordström, Fredrik; Ceberg, Crister; Ceberg, Sofie

    2018-04-01

    The purpose of this study was to develop a method to simulate breathing motion induced interplay effects for volumetric modulated arc therapy (VMAT), to verify the proposed method with measurements, and to use the method to investigate how interplay effects vary with different patient- and machine specific parameters. VMAT treatment plans were created on a virtual phantom in a treatment planning system (TPS). Interplay effects were simulated by dividing each plan into smaller sub-arcs using an in-house developed software and shifting the isocenter for each sub-arc to simulate a sin6 breathing motion in the superior–inferior direction. The simulations were performed for both flattening-filter (FF) and flattening-filter free (FFF) plans and for different breathing amplitudes, period times, initial breathing phases, dose levels, plan complexities, CTV sizes, and collimator angles. The resulting sub-arcs were calculated in the TPS, generating a dose distribution including the effects of motion. The interplay effects were separated from dose blurring and the relative dose differences to 2% and 98% of the CTV volume (ΔD98% and ΔD2%) were calculated. To verify the simulation method, measurements were carried out, both static and during motion, using a quasi-3D phantom and a motion platform. The results of the verification measurements during motion were comparable to the results of the static measurements. Considerable interplay effects were observed for individual fractions, with the minimum ΔD98% and maximum ΔD2% being  ‑16.7% and 16.2%, respectively. The extent of interplay effects was larger for FFF compared to FF and generally increased for higher breathing amplitudes, larger period times, lower dose levels, and more complex treatment plans. Also, the interplay effects varied considerably with the initial breathing phase, and larger variations were observed for smaller CTV sizes. In conclusion, a method to simulate motion induced interplay effects was

  11. Paediatric radiotherapy: Management and side effects

    International Nuclear Information System (INIS)

    Barare, C.

    2006-01-01

    This paper presents the general overview of management of children undergoing or who have undergone radiation therapy, and the associated effects. since the safe use of ionizing radiation in treatment of some children conditions is inevitable, the immediate and future effects need to be known and better understood for precise and accurate forecasting to benefit verses risk indicators. this is not withstanding the psychological trauma inflicted as some of the manifestations are visibly evident as the children grow

  12. Enhanced relative biological effectiveness of proton radiotherapy in tumor cells with internalized gold nanoparticles

    International Nuclear Information System (INIS)

    Polf, Jerimy C.; Gillin, Michael; Bronk, Lawrence F.; Driessen, Wouter H. P.; Arap, Wadih; Pasqualini, Renata

    2011-01-01

    The development and use of sensitizing agents to improve the effectiveness of radiotherapy have long been sought to improve our ability to treat cancer. In this letter, we have studied the relative biological effectiveness of proton beam radiotherapy on prostate tumor cells with and without internalized gold nanoparticles. The effectiveness of proton radiotherapy for the killing of prostate tumor cells was increased by approximately 15%-20% for those cells containing internalized gold nanoparticles.

  13. Enhanced relative biological effectiveness of proton radiotherapy in tumor cells with internalized gold nanoparticles

    Science.gov (United States)

    Polf, Jerimy C.; Bronk, Lawrence F.; Driessen, Wouter H. P.; Arap, Wadih; Pasqualini, Renata; Gillin, Michael

    2011-01-01

    The development and use of sensitizing agents to improve the effectiveness of radiotherapy have long been sought to improve our ability to treat cancer. In this letter, we have studied the relative biological effectiveness of proton beam radiotherapy on prostate tumor cells with and without internalized gold nanoparticles. The effectiveness of proton radiotherapy for the killing of prostate tumor cells was increased by approximately 15%–20% for those cells containing internalized gold nanoparticles. PMID:21915155

  14. Nonrandomized study comparing the effects of preoperative radiotherapy and daily administration of low-dose cisplatin with those radiotherapy alone for oral cancer

    International Nuclear Information System (INIS)

    Kurita, Hiroshi; Azegami, Takuya; Kobayashi, Hirokazu; Kurashina, Kenji; Tanaka, Kouichi; Kotani, Akira; Oguchi, Masahiko; Tamura, Minoru.

    1997-01-01

    The purpose of this study was to compare the effect of preoperative radiotherapy and daily administration of low-dose cisplatin with those of radiotherapy alone for oral cancer. Ten patients underwent preoperative radiotherapy of 30 to 40 Gy with concomitant daily administration of low-dose cisplatin (5 mg/body or 5 mg/m 2 ). Ten patients received external radiotherapy alone. The locoregional response rates (complete response and partial response) did not differ significantly between the two groups (80% for combined therapy and 60% for radiotherapy alone). On histopathologic evaluation of surgical specimens, however, the combined-therapy group (80%) had a higher response rate than did the radiotherapy-alone group (10%; p<0.01). We conclude that daily administration of low-dose cisplatin enhances the efficacy of radiotherapy against primary tumors. We also suggested that combined therapy may be beneficial as an initial treatment for oral cancer before a planned operation. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-04-01

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

  16. Effectiveness of Antioxidants in γ-Radiotherapy

    International Nuclear Information System (INIS)

    Kasrashvili, M.; Papava, M.; Enukidze, J.; Pavliashvili, A.

    2006-01-01

    During radiation-induced lesion of cells and tissues processes of free-radical oxidation play a significant role. A great number of investigations testify for decrease of the activity of antioxidative systems of the organism and changes in the content of nitrogen oxide (NO) in the process of ionizing irradiation. It has been shown that in the process of radiation lesion, NO can play both radio-protective and radio-toxic role, determined by redox-status of the organism. Therefore, the search of effective radioprotectors appears to be a topical problem of modern radiology. Vitamin C and and Plaferon-LB were used as radioprotectors, having antioxidative, antihypoxic, immunomodulating, and antiapoptotic charcter of the action. In the results of our investigations a conclusion should be done on effectiveness of pre- and post-radiation usage of the antioxidants. The development of optimal doses and their combined usage needs further studies. (author)

  17. Dose-volume histogram analysis for risk factors of radiation-induced rib fracture after hypofractionated proton beam therapy for hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kanemoto, Ayae

    2013-01-01

    Background: Radiation-induced rib fracture has been reported as a late complication after external radiotherapy to the chest. The purpose of this study was to clarify the characteristics and risk factors of rib fracture after hypofractionated proton beam therapy (PBT). Material and methods: The retrospective study comprised 67 patients with hepatocellular carcinoma who were treated using PBT of 66 Cobalt-Gray-equivalents [Gy (RBE)] in 10 fractions. We analyzed the patients' characteristics and determined dose-volume histograms (DVHs) for the irradiated ribs, and then estimated relationships between risk of fracture and several dose-volume parameters. An irradiated rib was defined to be any rib included in the area irradiated by PBT as determined by treatment-planning computed tomography. Results. Among the 67 patients, a total of 310 ribs were identified as irradiated ribs. Twenty-seven (8.7%) of the irradiated ribs developed fractures in 11 patients (16.4%). No significant relationships were seen between incidence of fracture and characteristics of patients, including sex, age, tumor size, tumor site, and follow-up period (p ≥ 0.05). The results of receiver operating characteristic curve analysis using DVH parameters demonstrated that the largest area under the curve (AUC) was observed for the volume of rib receiving a biologically effective dose of more than 60 Gy 3 (RBE) (V60) [The equivalent dose in 2 Gy fractions (EQD2); 36 Gy 3 ] and the AUCs of V30 to V120 (EQD2; 18-72 Gy 3 ) and D max to D 1 0 cm 3 were similar to that of V60. No significant relationships were seen for DVH parameters and intervals from PBT to incidence of fracture. Conclusion. DVH parameters are useful in predicting late adverse events of rib irradiation. This study identified that V60 was a most statistically significant parameter, and V30 to V120 and D max to D 1 0 cm 3 were also significant and clinically useful for estimating the risk of rib fracture after hypofractionated PBT

  18. Dose-volume histogram analysis for risk factors of radiation-induced rib fracture after hypofractionated proton beam therapy for hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kanemoto, Ayae [Proton Medical Research Center and Dept. of Radiation Oncology, Univ. of Tsukuba, Ibaraki (Japan)], e-mail: ayaek@pmrc.tsukuba.ac.jp [and others

    2013-04-15

    Background: Radiation-induced rib fracture has been reported as a late complication after external radiotherapy to the chest. The purpose of this study was to clarify the characteristics and risk factors of rib fracture after hypofractionated proton beam therapy (PBT). Material and methods: The retrospective study comprised 67 patients with hepatocellular carcinoma who were treated using PBT of 66 Cobalt-Gray-equivalents [Gy (RBE)] in 10 fractions. We analyzed the patients' characteristics and determined dose-volume histograms (DVHs) for the irradiated ribs, and then estimated relationships between risk of fracture and several dose-volume parameters. An irradiated rib was defined to be any rib included in the area irradiated by PBT as determined by treatment-planning computed tomography. Results. Among the 67 patients, a total of 310 ribs were identified as irradiated ribs. Twenty-seven (8.7%) of the irradiated ribs developed fractures in 11 patients (16.4%). No significant relationships were seen between incidence of fracture and characteristics of patients, including sex, age, tumor size, tumor site, and follow-up period (p {>=} 0.05). The results of receiver operating characteristic curve analysis using DVH parameters demonstrated that the largest area under the curve (AUC) was observed for the volume of rib receiving a biologically effective dose of more than 60 Gy{sub 3} (RBE) (V60) [The equivalent dose in 2 Gy fractions (EQD2); 36 Gy{sub 3}] and the AUCs of V30 to V120 (EQD2; 18-72 Gy{sub 3}) and D{sub max} to D{sub 1}0{sub cm}{sup 3} were similar to that of V60. No significant relationships were seen for DVH parameters and intervals from PBT to incidence of fracture. Conclusion. DVH parameters are useful in predicting late adverse events of rib irradiation. This study identified that V60 was a most statistically significant parameter, and V30 to V120 and D{sub max} to D{sub 1}0{sub cm}{sup 3} were also significant and clinically useful for estimating

  19. Treatment of Locally Advanced Vaginal Cancer With Radiochemotherapy and Magnetic Resonance Image-Guided Adaptive Brachytherapy: Dose-Volume Parameters and First Clinical Results

    Energy Technology Data Exchange (ETDEWEB)

    Dimopoulos, Johannes C.A. [Department of Radiation Oncology, Metropolitan Hospital, Athens (Greece); Schmid, Maximilian P., E-mail: maximilian.schmid@akhwien.at [Department of Radiotherapy, Medical University of Vienna, Vienna (Austria); Fidarova, Elena; Berger, Daniel; Kirisits, Christian; Poetter, Richard [Department of Radiotherapy, Medical University of Vienna, Vienna (Austria)

    2012-04-01

    Purpose: To investigate the clinical feasibility of magnetic resonance image-guided adaptive brachytherapy (IGABT) for patients with locally advanced vaginal cancer and to report treatment outcomes. Methods and Materials: Thirteen patients with vaginal cancer were treated with external beam radiotherapy (45-50.4 Gy) plus IGABT with or without chemotherapy. Distribution of International Federation of Gynecology and Obstetrics stages among patients were as follows: 4 patients had Stage II cancer, 5 patients had Stage III cancer, and 4 patients had Stage IV cancer. The concept of IGABT as developed for cervix cancer was transferred and adapted for vaginal cancer, with corresponding treatment planning and reporting. Doses were converted to the equivalent dose in 2 Gy, applying the linear quadratic model ({alpha}/{beta} = 10 Gy for tumor; {alpha}/{beta} = 3 for organs at risk). Endpoints studied were gross tumor volume (GTV), dose-volume parameters for high-risk clinical target volume (HRCTV), and organs at risk, local control (LC), adverse side effects, and survival. Results: The mean GTV ({+-} 1 standard deviation) at diagnosis was 45.3 ({+-}30) cm{sup 3}, and the mean GTV at brachytherapy was 10 ({+-}14) cm{sup 3}. The mean D90 for the HRCTV was 86 ({+-}13) Gy. The mean D2cc for bladder, urethra, rectum, and sigmoid colon were 80 ({+-}20) Gy, 76 ({+-}16) Gy, 70 ({+-}9) Gy, and 60 ({+-}9) Gy, respectively. After a median follow-up of 43 months (range, 19-87 months), one local recurrence and two distant metastases cases were observed. Actuarial LC and overall survival rates at 3 years were 92% and 85%. One patient with Stage IVA and 1 patient with Stage III disease experienced fistulas (one vesicovaginal, one rectovaginal), and 1 patient developed periurethral necrosis. Conclusions: The concept of IGABT, originally developed for treating cervix cancer, appears to be applicable to vaginal cancer treatment with only minor adaptations. Dose-volume parameters for HRCTV and

  20. Mutational effects of radiotherapy and chemotherapy

    International Nuclear Information System (INIS)

    Morley, A.A.

    1988-01-01

    In studies of mutagenesis, lymphocytes have been used as nucleated mammalian cells rather than as specific immune cells. Nevertheless, there are good data that both chemotherapy and radiation result in long-term effects on the immune system both in experimental animals and in humans, and produce long-term qualitative and/or quantitative changes in various immune populations. The peripheral blood lymphocyte, however, may well be quite a good model for the hemopoietic stem cell, since both cells are normally G/sub o/ and both have very extensive proliferative capacity. Thus individual circulating human T lymphocytes are able to give rise to between 10/sup 8/ and 10/sup 32/ descendants, and individual murine stem cells are capable of completely restoring hemopoiesis, implying that they are able to give rise to at least 10/sup 11/-10/sup 12/ descendants. If mutations occur in hemopoietic stem cells as they do in T lymphocytes, then one could readily envisage how late effects such as carcinogenesis and proliferative failure might result

  1. Adverse effect after external radiotherapy for brain tumors

    International Nuclear Information System (INIS)

    Yoshii, Yoshihiko; Takano, Shingo; Yanaka, Kiyoyuki

    1989-01-01

    This report discusses the effects on normal brain tissue of radiotherapy in relation to age and irradiation dose as determined from whole-brain sections of the autopsied brains with tumors. Twenty four patients (7 glioblastomas, 2 benign gliomas, 12 brain metastases, 2 malignant lymphomas, and 1 pituitary adenoma) older than 65 years (aged), and 17 younger than 65 years (non-aged) were treated by cobalt- or linear accelerator radiotherapy. Nine patients without brain disease (4 aged and 5 non-aged) were used as a control group. The histological findings were evaluated by grading the small and capillary vessels, fibrinoid necrosis, and myelination in the white matter in whole-brain sections. Those findings were compared to the irradiation doses within all radiation fields in whole-brain sections corresponding to CT scans. Hyalinization of the small vessels was observed within the postradiation 12 months in fields exposed to total doses of less than 800 neuret. Hyalinization of the capillary vessels was greater in the irradiated group than in the control group. Demyelination was observed within the postradiation 12 months in fields irradiated by more than 800 neuret in aged patients and in fields irradiated by less than 800 neuret in non-aged patients. Fibrinoid necrosis was observed after the post-radiation 12 months in fields irradiated by less than 800 neuret in aged patients and in fields irradiated by more than 800 neuret in non-aged patients. It is worth noting that in non-aged patients with brain tumors, adverse effects of radiotherapy on vessels and parenchyma were very high even in low-dose radiation areas; and in aged patients fibrinoid necrosis, which indicates irreversible damage of vessels, was observed in low-dose radiation areas. (author)

  2. Acute small bowel toxicity and preoperative chemoradiotherapy for rectal cancer: Investigating dose-volume relationships and role for inverse planning

    International Nuclear Information System (INIS)

    Tho, Lye Mun; Glegg, Martin; Paterson, Jennifer; Yap, Christina; MacLeod, Alice; McCabe, Marie; McDonald, Alexander C.

    2006-01-01

    Purpose: The relationship between volume of irradiated small bowel (VSB) and acute toxicity in rectal cancer radiotherapy is poorly quantified, particularly in patients receiving concurrent preoperative chemoradiotherapy. Using treatment planning data, we studied a series of such patients. Methods and Materials: Details of 41 patients with locally advanced rectal cancer were reviewed. All received 45 Gy in 25 fractions over 5 weeks, 3-4 fields three-dimensional conformal radiotherapy with daily 5-fluorouracil and folinic acid during Weeks 1 and 5. Toxicity was assessed prospectively in a weekly clinic. Using computed tomography planning software, the VSB was determined at 5 Gy dose intervals (V 5 , V 1 , etc.). Eight patients with maximal VSB had dosimetry and radiobiological modeling outcomes compared between inverse and conformal three-dimensional planning. Results: VSB correlated strongly with diarrheal severity at every dose level (p 5 and V 15 . Conclusions: A strong dose-volume relationship exists between VSB and acute diarrhea at all dose levels during preoperative chemoradiotherapy. Our constructed model may be useful in predicting toxicity, and this has been derived without the confounding influence of surgical excision on bowel function. Inverse planning can reduce calculated dose to small bowel and late NTCP, and its clinical role warrants further investigation

  3. Inhibitory effect of sequential combined chemotherapy and radiotherapy on growth of implanted tumor in mice

    International Nuclear Information System (INIS)

    Okada, Kouji

    1983-01-01

    Sequential chemotherapy using FT-207, adriamycin and mitomycin C followed by radiotherapy was attempted to achieve effective inhibition against implanted tumor in C57BL/6 black mice bearing YM-12 tumors. Sequential combined chemotherapy was more effective than single drug chemotherapy or combined chemotherapy of other drugs. Addition of radiotherapy to the sequential combined chemotherapy was successful for enhancing therapeutic effect. (author)

  4. Dose-rate effects in external beam radiotherapy redux

    International Nuclear Information System (INIS)

    Ling, C. Clifton; Gerweck, Leo E.; Zaider, Marco; Yorke, Ellen

    2010-01-01

    Recent developments in external beam radiotherapy, both in technical advances and in clinical approaches, have prompted renewed discussions on the potential influence of dose-rate on radio-response in certain treatment scenarios. We consider the multiple factors that influence the dose-rate effect, e.g. radical recombination, the kinetics of sublethal damage repair for tumors and normal tissues, the difference in α/β ratio for early and late reacting tissues, and perform a comprehensive literature review. Based on radiobiological considerations and the linear-quadratic (LQ) model we estimate the influence of overall treatment time on radio-response for specific clinical situations. As the influence of dose-rate applies to both the tumor and normal tissues, in oligo-fractionated treatment using large doses per fraction, the influence of delivery prolongation is likely important, with late reacting normal tissues being generally more sensitive to the dose-rate effect than tumors and early reacting tissues. In conventional fractionated treatment using 1.8-2 Gy per fraction and treatment times of 2-10 min, the influence of dose-rate is relatively small. Lastly, the dose-rate effect in external beam radiotherapy is governed by the overall beam-on-time, not by the average linac dose-rate, nor by the instantaneous dose-rate within individual linac pulses which could be as high as 3 x 10 6 MU/min.

  5. Hypofractionated Adjuvant Whole Breast Radiotherapy: Progress and Prospects

    International Nuclear Information System (INIS)

    Yarnold, John; Haviland, Joanne

    2010-01-01

    Published results of randomised trials involving >7000 women confirm the safety and efficacy of hypofractionated schedules of adjuvant radiotherapy for women with early breast cancer using fraction sizes between 2 and 3 Gy assuming appropriate downward adjustments to total dose. Unnecessary concerns relating to heart tolerance, suboptimal dose distribution and duration of follow up need not discourage the routine adoption of 15- or 16-fraction schedules in women treated by breast conservation surgery for early breast cancer. Regardless of fractionation regimen, dose escalation to the index quadrant in high risk subgroups will result in a greater relative increase in late adverse effects than tumour control, a therapeutic disadvantage that can only be overcome by exploiting a marked dose-volume effect. A 15-fraction schedule of whole breast radiotherapy is unlikely to represent the lower limits of hypofractionation, and the preliminary results of a 5-fraction regimen are encouraging

  6. Radiotherapy and antitumor immunity. An immunomodifying effect of ionizing radiation

    International Nuclear Information System (INIS)

    Klimovich, V.B.

    1983-01-01

    It has been found that a tumor is formed and spread under the influence of opposite but not mutually exlusive immune reactions. Radiation effect along with direct injury of tumoral cells and feeding neoplasms vessels changes the established equilibrium of immunologic factors, therefore it should be considered as immunomodifying one. The wide spread opinion according to which the therapeutic effect in case of radiotherapy is attained despite its depressive effect on immunity, should be revised as not corresponding to the facts. The data available allow one to assume that immunologic factors may play an essential role in realization of therapeutic effect of irradiation as well as in limitation of its efficiency. Investigations into immunologic aspects of oncology and radiology should be therefore directed to the search of methods of control of immune reactions of organism - the tumor bearer. This may discover considerable reserves of increasing radiotherapeutic efficiency

  7. Cost-effectiveness of modern radiotherapy techniques in locally advanced pancreatic cancer.

    Science.gov (United States)

    Murphy, James D; Chang, Daniel T; Abelson, Jon; Daly, Megan E; Yeung, Heidi N; Nelson, Lorene M; Koong, Albert C

    2012-02-15

    Radiotherapy may improve the outcome of patients with pancreatic cancer but at an increased cost. In this study, the authors evaluated the cost-effectiveness of modern radiotherapy techniques in the treatment of locally advanced pancreatic cancer. A Markov decision-analytic model was constructed to compare the cost-effectiveness of 4 treatment regimens: gemcitabine alone, gemcitabine plus conventional radiotherapy, gemcitabine plus intensity-modulated radiotherapy (IMRT); and gemcitabine with stereotactic body radiotherapy (SBRT). Patients transitioned between the following 5 health states: stable disease, local progression, distant failure, local and distant failure, and death. Health utility tolls were assessed for radiotherapy and chemotherapy treatments and for radiation toxicity. SBRT increased life expectancy by 0.20 quality-adjusted life years (QALY) at an increased cost of $13,700 compared with gemcitabine alone (incremental cost-effectiveness ratio [ICER] = $69,500 per QALY). SBRT was more effective and less costly than conventional radiotherapy and IMRT. An analysis that excluded SBRT demonstrated that conventional radiotherapy had an ICER of $126,800 per QALY compared with gemcitabine alone, and IMRT had an ICER of $1,584,100 per QALY compared with conventional radiotherapy. A probabilistic sensitivity analysis demonstrated that the probability of cost-effectiveness at a willingness to pay of $50,000 per QALY was 78% for gemcitabine alone, 21% for SBRT, 1.4% for conventional radiotherapy, and 0.01% for IMRT. At a willingness to pay of $200,000 per QALY, the probability of cost-effectiveness was 73% for SBRT, 20% for conventional radiotherapy, 7% for gemcitabine alone, and 0.7% for IMRT. The current results indicated that IMRT in locally advanced pancreatic cancer exceeds what society considers cost-effective. In contrast, combining gemcitabine with SBRT increased clinical effectiveness beyond that of gemcitabine alone at a cost potentially acceptable by

  8. The effect of obesity levels on irradiated small bowel volume in belly board with small bowel displacement device for rectal cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Young; Kim, Joo Ho; Park, Hyo Kuk; Cho, Jeong Hee [Dept. of Radiation Oncology, Yonsei Cancer Center, Yonsei University Health System, Seoul (Korea, Republic of)

    2013-03-15

    For radiotherapy in rectal cancer patients treated with small bowel displacement device (SBDD) and belly board, We will suggest new indication of using SBDD depending on obesity index by analyzing correlation between obesity and irradiated small bowel volume. In this study, We reviewed 29 rectal cancer patients who received pelvic radiation therapy with belly board and SBDD from January to April in 2012. We only analyzed those patients treated with three-field technique (PA and both LAT) on 45 Gy (1.8 Gy/fx). We measured patients' height, weight, body mass index (BMI), waist-hip ratio (WHR) and divided BMI into two groups.(≥23:BMI=group 1, <23:BMI=group 2) We performed a statistical analysis to evaluate correlation between total volume of bladder (TV{sub bldder}), obesity index and high dose volume of small bowel (small bowel volume irradiated at 90% of prescribed dose, HDV{sub sb}), low dose volume of small bowel (small bowel volume irradiated at 33% of prescribed dose, LDV{sub sb}). The result shows, gender, WHR and status of pre operative or post operative do not greatly affect HDV{sub sb} and LDV{sub sb}. Statistical result shows, there are significant correlation between HDV{sub sb} and BMI (p<0.04), HDV{sub sb} and TV{sub bladder} (p<0.01), LDV{sub sb} and TV{sub bladder} (p<0.01). BMI seems to correlate with HDV{sub sb} but does not with LDV{sub sb} (p>0.05). There are negative correlation between HDV{sub sb} and BMI, TV{sub bladder} and HDV{sub sb}, TV{sub bladder} and LDV{sub sb} . Especially, BMI group1 has more effective and negative correlation with HDV{sub sb} (p=0.027) than in BMI group 2. In the case of BMI group 1, TV{sub bladder} has significant negative correlation with HDV{sub sb} and LDV{sub sb} (p<0.04). In conclusions, we confirmed that Using SBDD with belly board in BMI group 1 could more effectively reduce irradiated small bowel volume in radiation therapy for rectal cancer. Therefore, We suggest using belly board with SBDD in order

  9. The effect of obesity levels on irradiated small bowel volume in belly board with small bowel displacement device for rectal cancer radiotherapy

    International Nuclear Information System (INIS)

    Kim, Se Young; Kim, Joo Ho; Park, Hyo Kuk; Cho, Jeong Hee

    2013-01-01

    For radiotherapy in rectal cancer patients treated with small bowel displacement device (SBDD) and belly board, We will suggest new indication of using SBDD depending on obesity index by analyzing correlation between obesity and irradiated small bowel volume. In this study, We reviewed 29 rectal cancer patients who received pelvic radiation therapy with belly board and SBDD from January to April in 2012. We only analyzed those patients treated with three-field technique (PA and both LAT) on 45 Gy (1.8 Gy/fx). We measured patients' height, weight, body mass index (BMI), waist-hip ratio (WHR) and divided BMI into two groups.(≥23:BMI=group 1, <23:BMI=group 2) We performed a statistical analysis to evaluate correlation between total volume of bladder (TV bldder ), obesity index and high dose volume of small bowel (small bowel volume irradiated at 90% of prescribed dose, HDV sb ), low dose volume of small bowel (small bowel volume irradiated at 33% of prescribed dose, LDV sb ). The result shows, gender, WHR and status of pre operative or post operative do not greatly affect HDV sb and LDV sb . Statistical result shows, there are significant correlation between HDV sb and BMI (p<0.04), HDV sb and TV bladder (p<0.01), LDV sb and TV bladder (p<0.01). BMI seems to correlate with HDV sb but does not with LDV sb (p>0.05). There are negative correlation between HDV sb and BMI, TV bladder and HDV sb , TV bladder and LDV sb . Especially, BMI group1 has more effective and negative correlation with HDV sb (p=0.027) than in BMI group 2. In the case of BMI group 1, TV bladder has significant negative correlation with HDV sb and LDV sb (p<0.04). In conclusions, we confirmed that Using SBDD with belly board in BMI group 1 could more effectively reduce irradiated small bowel volume in radiation therapy for rectal cancer. Therefore, We suggest using belly board with SBDD in order to reduce the small bowel toxicity in rectal radiotherapy, if patients' BMI is above 23

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

    Directory of Open Access Journals (Sweden)

    Jian-Jun Han

    2016-07-01

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

  11. Improved dose-volume histogram estimates for radiopharmaceutical therapy by optimizing quantitative SPECT reconstruction parameters

    Science.gov (United States)

    Cheng, Lishui; Hobbs, Robert F.; Segars, Paul W.; Sgouros, George; Frey, Eric C.

    2013-06-01

    In radiopharmaceutical therapy, an understanding of the dose distribution in normal and target tissues is important for optimizing treatment. Three-dimensional (3D) dosimetry takes into account patient anatomy and the nonuniform uptake of radiopharmaceuticals in tissues. Dose-volume histograms (DVHs) provide a useful summary representation of the 3D dose distribution and have been widely used for external beam treatment planning. Reliable 3D dosimetry requires an accurate 3D radioactivity distribution as the input. However, activity distribution estimates from SPECT are corrupted by noise and partial volume effects (PVEs). In this work, we systematically investigated OS-EM based quantitative SPECT (QSPECT) image reconstruction in terms of its effect on DVHs estimates. A modified 3D NURBS-based Cardiac-Torso (NCAT) phantom that incorporated a non-uniform kidney model and clinically realistic organ activities and biokinetics was used. Projections were generated using a Monte Carlo (MC) simulation; noise effects were studied using 50 noise realizations with clinical count levels. Activity images were reconstructed using QSPECT with compensation for attenuation, scatter and collimator-detector response (CDR). Dose rate distributions were estimated by convolution of the activity image with a voxel S kernel. Cumulative DVHs were calculated from the phantom and QSPECT images and compared both qualitatively and quantitatively. We found that noise, PVEs, and ringing artifacts due to CDR compensation all degraded histogram estimates. Low-pass filtering and early termination of the iterative process were needed to reduce the effects of noise and ringing artifacts on DVHs, but resulted in increased degradations due to PVEs. Large objects with few features, such as the liver, had more accurate histogram estimates and required fewer iterations and more smoothing for optimal results. Smaller objects with fine details, such as the kidneys, required more iterations and less

  12. Influence of pauses in irradiation on radiotherapy effect

    International Nuclear Information System (INIS)

    Skladowski, K.; Tarnawski, R.; Swierniak, A.

    1999-01-01

    The main goal of the study was demonstration, that pauses in radiotherapy of head and neck neoplasms dramatically influence on therapy results estimated as tumor control probability (TCP). The reason of this phenomenon is duplication of tumor cell proliferation during pauses in radiotherapy. This hypothesis is demonstrated on the analysis of statistical models, which parameters were estimated from the data of 1350 patients treated with radiotherapy in Center of Oncology in 1980-1989

  13. Dose-volume histograms based on serial intravascular ultrasound: a calculation model for radioactive stents

    International Nuclear Information System (INIS)

    Kirisits, Christian; Wexberg, Paul; Gottsauner-Wolf, Michael; Pokrajac, Boris; Ortmann, Elisabeth; Aiginger, Hannes; Glogar, Dietmar; Poetter, Richard

    2001-01-01

    Background and purpose: Radioactive stents are under investigation for reduction of coronary restenosis. However, the actual dose delivered to specific parts of the coronary artery wall based on the individual vessel anatomy has not been determined so far. Dose-volume histograms (DVHs) permit an estimation of the actual dose absorbed by the target volume. We present a method to calculate DVHs based on intravascular ultrasound (IVUS) measurements to determine the dose distribution within the vessel wall. Materials and methods: Ten patients were studied by intravascular ultrasound after radioactive stenting (BX Stent, P-32, 15-mm length) to obtain tomographic cross-sections of the treated segments. We developed a computer algorithm using the actual dose distribution of the stent to calculate differential and cumulative DVHs. The minimal target dose, the mean target dose, the minimal doses delivered to 10 and 90% of the adventitia (DV10, DV90), and the percentage of volume receiving a reference dose at 0.5 mm from the stent surface cumulated over 28 days were derived from the DVH plots. Results were expressed as mean±SD. Results: The mean activity of the stents was 438±140 kBq at implantation. The mean reference dose was 111±35 Gy, whereas the calculated mean target dose within the adventitia along the stent was 68±20 Gy. On average, DV90 and DV10 were 33±9 Gy and 117±41 Gy, respectively. Expanding the target volume to include 2.5-mm-long segments at the proximal and distal ends of the stent, the calculated mean target dose decreased to 55±17 Gy, and DV 90 and DV 10 were 6.4±2.4 Gy and 107±36 Gy, respectively. Conclusions: The assessment of DVHs seems in principle to be a valuable tool for both prospective and retrospective analysis of dose-distribution of radioactive stents. It may provide the basis to adapt treatment planning in coronary brachytherapy to the common standards of radiotherapy

  14. The effects of low-dose radiotherapy on fresh osteochondral allografts: An experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Uğur Gönç

    2016-10-01

    Conclusion: In osteochondral massive allograft transplantations, the immune reaction of the host could be precluded with radiotherapy, and the side-effects can be prevented by low-dose fractionated regimen. The total dose of fractionated radiotherapy for an immune suppression should be adjusted not to damage the cartilage tissue, but to avoid articular degeneration in the long term.

  15. Side effects after radiotherapy of age-related macular degeneration with the Nijmegen technique.

    NARCIS (Netherlands)

    Hoyng, C.B.; Tromp, A.I.; Meulendijks, C.F.M.; Leys, A.; Maazen, R.W.M. van der; Deutman, A.F.; Vingerling, J.R.

    2002-01-01

    BACKGROUND: In a randomized trial concerning radiotherapy for age-related macular degeneration, fluorescein angiograms were taken of controls and patients. In this study the frequency of side effects in eyes receiving radiotherapy with the Nijmegen technique is compared with the findings in the eyes

  16. Optimization of stereotactically-guided conformal treatment planning of sellar and parasellar tumors, based on normal brain dose volume histograms

    International Nuclear Information System (INIS)

    Perks, Julian R.; Jalali, Rakesh; Cosgrove, Vivian P.; Adams, Elizabeth J.; Shepherd, Stephen F.; Warrington, Alan P.; Brada, Michael

    1999-01-01

    Purpose: To investigate the optimal treatment plan for stereo tactically-guided conformal radiotherapy (SCRT) of sellar and parasellar lesions, with respect to sparing normal brain tissue, in the context of routine treatment delivery, based on dose volume histogram analysis. Methods and Materials: Computed tomography (CT) data sets for 8 patients with sellar- and parasellar-based tumors (6 pituitary adenomas and 2 meningiomas) have been used in this study. Treatment plans were prepared for 3-coplanar and 3-, 4-, 6-, and 30-noncoplanar-field arrangements to obtain 95% isodose coverage of the planning target volume (PTV) for each plan. Conformal shaping was achieved by customized blocks generated with the beams eye view (BEV) facility. Dose volume histograms (DVH) were calculated for the normal brain (excluding the PTV), and comparisons made for normal tissue sparing for all treatment plans at ≥80%, ≥60%, and ≥40% of the prescribed dose. Results: The mean volume of normal brain receiving ≥80% and ≥60% of the prescribed dose decreased by 22.3% (range 14.8-35.1%, standard deviation σ = 7.5%) and 47.6% (range 25.8-69.1%, σ 13.2%), respectively, with a 4-field noncoplanar technique when compared with a conventional 3-field coplanar technique. Adding 2 further fields, from 4-noncoplanar to 6-noncoplanar fields reduced the mean normal brain volume receiving ≥80% of the prescribed dose by a further 4.1% (range -6.5-11.8%, σ = 6.4%), and the volume receiving ≥60% by 3.3% (range -5.5-12.2%, σ = 5.4%), neither of which were statistically significant. Each case must be considered individually however, as a wide range is seen in the volume spared when increasing the number of fields from 4 to 6. Comparing the 4- and 6-field noncoplanar techniques to a 30-field conformal field approach (simulating a dynamic arc plan) revealed near-equivalent normal tissue sparing. Conclusion: Four to six widely spaced, fixed-conformal fields provide the optimum class solution

  17. Multiple local minima in IMRT optimization based on dose-volume criteria

    International Nuclear Information System (INIS)

    Wu Qiuwen; Mohan, Radhe

    2002-01-01

    Multiple local minima traps are known to exist in dose-volume and dose-response objective functions. Nevertheless, their presence and consequences are not considered impediments in finding satisfactory solutions in routine optimization of IMRT plans using gradient methods. However, there is often a concern that a significantly superior solution may exist unbeknownst to the planner and that the optimization process may not be able to reach it. We have investigated the soundness of the assumption that the presence of multiple minima traps can be ignored. To find local minima, we start the optimization process a large number of times with random initial intensities. We investigated whether the occurrence of local minima depends upon the choice of the objective function parameters and the number of variables and whether their existence is an impediment in finding a satisfactory solution. To learn about the behavior of multiple minima, we first used a symmetric cubic phantom containing a cubic target and an organ-at-risk surrounding it to optimize the beam weights of two pairs of parallel-opposed beams using a gradient technique. The phantom studies also served to test our software. Objective function parameters were chosen to ensure that multiple minima would exist. Data for 500 plans, optimized with random initial beam weights, were analyzed. The search process did succeed in finding the local minima and showed that the number of minima depends on the parameters of the objective functions. It was also found that the consequences of local minima depended on the number of beams. We further searched for the multiple minima in intensity-modulated treatment plans for a head-and-neck case and a lung case. In addition to the treatment plan scores and the dose-volume histograms, we examined the dose distributions and intensity patterns. We did not find any evidence that multiple local minima affect the outcome of optimization using gradient techniques in any clinically

  18. A Dose-Volume Analysis of Magnetic Resonance Imaging-Aided High-Dose-Rate Image-Based Interstitial Brachytherapy for Uterine Cervical Cancer

    International Nuclear Information System (INIS)

    Yoshida, Ken; Yamazaki, Hideya; Takenaka, Tadashi; Kotsuma, Tadayuki; Yoshida, Mineo; Furuya, Seiichi; Tanaka, Eiichi; Uegaki, Tadaaki; Kuriyama, Keiko; Matsumoto, Hisanobu; Yamada, Shigetoshi; Ban, Chiaki

    2010-01-01

    Purpose: To investigate the feasibility of our novel image-based high-dose-rate interstitial brachytherapy (HDR-ISBT) for uterine cervical cancer, we evaluated the dose-volume histogram (DVH) according to the recommendations of the Gynecological GEC-ESTRO Working Group for image-based intracavitary brachytherapy (ICBT). Methods and Materials: Between June 2005 and June 2007, 18 previously untreated cervical cancer patients were enrolled. We implanted magnetic resonance imaging (MRI)-available plastic applicators by our unique ambulatory technique. Total treatment doses were 30-36 Gy (6 Gy per fraction) combined with external beam radiotherapy (EBRT). Treatment plans were created based on planning computed tomography with MRI as a reference. DVHs of the high-risk clinical target volume (HR CTV), intermediate-risk CTV (IR CTV), and the bladder and rectum were calculated. Dose values were biologically normalized to equivalent doses in 2-Gy fractions (EQD 2 ). Results: The median D90 (HR CTV) and D90 (IR CTV) per fraction were 6.8 Gy (range, 5.5-7.5) and 5.4 Gy (range, 4.2-6.3), respectively. The median V100 (HR CTV) and V100 (IR CTV) were 98.4% (range, 83-100) and 81.8% (range, 64-93.8), respectively. When the dose of EBRT was added, the median D90 and D100 of HR CTV were 80.6 Gy (range, 65.5-96.6) and 62.4 Gy (range, 49-83.2). The D 2cc of the bladder was 62 Gy (range, 51.4-89) and of the rectum was 65.9 Gy (range, 48.9-76). Conclusions: Although the targets were advanced and difficult to treat effectively by ICBT, MRI-aided image-based ISBT showed favorable results for CTV and organs at risk compared with previously reported image-based ICBT results.

  19. A dose-volume analysis of magnetic resonance imaging-aided high-dose-rate image-based interstitial brachytherapy for uterine cervical cancer.

    Science.gov (United States)

    Yoshida, Ken; Yamazaki, Hideya; Takenaka, Tadashi; Kotsuma, Tadayuki; Yoshida, Mineo; Furuya, Seiichi; Tanaka, Eiichi; Uegaki, Tadaaki; Kuriyama, Keiko; Matsumoto, Hisanobu; Yamada, Shigetoshi; Ban, Chiaki

    2010-07-01

    To investigate the feasibility of our novel image-based high-dose-rate interstitial brachytherapy (HDR-ISBT) for uterine cervical cancer, we evaluated the dose-volume histogram (DVH) according to the recommendations of the Gynecological GEC-ESTRO Working Group for image-based intracavitary brachytherapy (ICBT). Between June 2005 and June 2007, 18 previously untreated cervical cancer patients were enrolled. We implanted magnetic resonance imaging (MRI)-available plastic applicators by our unique ambulatory technique. Total treatment doses were 30-36 Gy (6 Gy per fraction) combined with external beam radiotherapy (EBRT). Treatment plans were created based on planning computed tomography with MRI as a reference. DVHs of the high-risk clinical target volume (HR CTV), intermediate-risk CTV (IR CTV), and the bladder and rectum were calculated. Dose values were biologically normalized to equivalent doses in 2-Gy fractions (EQD(2)). The median D90 (HR CTV) and D90 (IR CTV) per fraction were 6.8 Gy (range, 5.5-7.5) and 5.4 Gy (range, 4.2-6.3), respectively. The median V100 (HR CTV) and V100 (IR CTV) were 98.4% (range, 83-100) and 81.8% (range, 64-93.8), respectively. When the dose of EBRT was added, the median D90 and D100 of HR CTV were 80.6 Gy (range, 65.5-96.6) and 62.4 Gy (range, 49-83.2). The D(2cc) of the bladder was 62 Gy (range, 51.4-89) and of the rectum was 65.9 Gy (range, 48.9-76). Although the targets were advanced and difficult to treat effectively by ICBT, MRI-aided image-based ISBT showed favorable results for CTV and organs at risk compared with previously reported image-based ICBT results. (c) 2010 Elsevier Inc. All rights reserved.

  20. Bystander effects and their implications for clinical radiotherapy

    International Nuclear Information System (INIS)

    Munro, Alastair J

    2009-01-01

    Radiation-induced bystander effects are defined as those biological effects expressed, after irradiation, by cells whose nuclei have not been directly irradiated. Radiation oncologists are only gradually beginning to appreciate the clinical relevance of radiation-induced bystander effects and associated phenomena: adaptive responses, genomic instability and abscopal effects. Incorporating bystander effects into the science underpinning clinical radiotherapy will involve moving beyond simple mechanistic models and towards a more systems-based approach. It is, given the protean nature of bystander effects, difficult to devise a coherent research strategy to investigate the clinical impact and relevance of bystander phenomena. Epidemiological approaches will be required, the traditional research models based on randomised controlled trials are unlikely to be adequate for the task. Any consideration of bystander effects challenges not only clinicians' preconceptions concerning the effects of radiation on tumours and normal tissues but also their ingenuity. This review covers, from a clinical perspective, the issues and problems associated with radiation-induced bystander effects.

  1. Effect of pelvic radiotherapy for prostrate cancer on bowel, bladder and sexual functions

    International Nuclear Information System (INIS)

    Saif-ur-Rahman; Ali, N.

    2002-01-01

    Objective: To study the effects of pelvic radiotherapy for prostate cancer on sexual, bowel and urinary functions. Study Design: a prospective cohort study. Place and duration of study: The study was conducted at Shaukat Khanum Memorial Cancer Hospital, Lahore from July 1998 to January 2000. Patients and Method: This study included 52 patients with diagnosis of prostate cancer who were given external beam pelvic radiotherapy. The effects of pelvic radiotherapy on their sexual, bowel and bladder functions were calculated at 6, 12 and 18 months and mean composite scores for each entity were examined. Results: Decrease in sexual function (up to 35%) was most significant observation followed by bowel dysfunction (10-12%). Bladder function deranged early during radiotherapy but there was no remarkable bladder dysfunction, overall a good proportion of patients (70 - 72%) felt satisfied with their treatment by external beam radiotherapy. By lapse of time there was gradual worsening of erectile function especially after a couple of months of pelvic radiotherapy, while bowel and bladder functions improved 8-12 months post radiotherapy. Conclusion: Proper counselling of patients regarding potential side effects of pelvic radiotherapy can make them understand the outcome of treatment. (author)

  2. Effects of stimulated repopulation on oral mucositis during conventional radiotherapy

    International Nuclear Information System (INIS)

    Doerr, W.; Jacubek, A.; Kummermehr, J.; Herrmann, Th.; Doelling-Jochem, I.; Eckelt, U.

    1995-01-01

    The effect of local conditioning of human oral mucosa by silver nitrate solution (3%) on epithelial proliferation rates was tested in 11 healthy volunteers by in vitro labelling of biopsies with tritiated thymidine. Compared to control biopsies from 13 volunteers, stimulation over 3 days, 3 times per day, yielded a significant (p = 0.006) increase in the epithelial labelling index (LI) from 4.75 ± 0.32% to 6.85 ± 0.65%, i.e., by 44%. The increase in the absolute number of labelled cells per mm epithelial length was dependent on the overall cell density at the various intraoral sites and varied between 45% in the maxillary vestibule and 91% at the floor of the mouth. In an analysis of variance, stimulation turned out to be the most important source causing the effect (p = 0.011 for LI and 0.015 for labelled cells per mm). In a radiotherapy trial with conventional postoperative treatment with 5 x 2 Gy/week to a total dose of 60 Gy in 6 weeks, the left buccal mucosa in 10 patients with squamous cell carcinomas of the head and neck was conditioned (3% silver nitrate, 3 times per day, 5 days before and the first 2 days of radiotherapy) while the contralateral mucosa, receiving an identical dose, served as individual control. Mucositis scores according to the EORTC/RTOG or the Dische system showed that the time course and severity of the mucosal response was almost identical in both cheeks, which is in clear contrast to a previous clinical study (Maciejewski et al. Radiother. Oncol. 22, 7-11, 1991). Differences in radiation dose intensity, i.e., weekly dose, in these studies are discussed as a tentative explanation for the different clinical findings

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  4. Adjuvant radiotherapy after breast conserving surgery - a comparative effectiveness research study.

    Science.gov (United States)

    Corradini, Stefanie; Niyazi, Maximilian; Niemoeller, Olivier M; Li, Minglun; Roeder, Falk; Eckel, Renate; Schubert-Fritschle, Gabriele; Scheithauer, Heike R; Harbeck, Nadia; Engel, Jutta; Belka, Claus

    2015-01-01

    The purpose of this retrospective outcome study was to validate the effectiveness of postoperative radiotherapy in breast conserving therapy (BCT) and to evaluate possible causes for omission of radiotherapy after breast conserving surgery (BCS) in a non-trial population. Data were provided by the population-based Munich Cancer Registry. The study included epidemiological data of 30.811 patients diagnosed with breast cancer from 1998 to 2012. The effect of omitting radiotherapy was analysed using Kaplan-Meier-estimates and Cox proportional hazard regression. Variables predicting omission of radiotherapy were analysed using multivariate logistic regression. Use of postoperative radiotherapy after BCS was associated with significant improvements in local control and survival. 10-year loco-regional recurrence-free-survival was 90.8% with postoperative radiotherapy vs. 77.6% with surgery alone (pstudy shows a decrease in local control and a survival disadvantage if postoperative radiotherapy after breast conserving surgery is omitted in an unselected cohort of primary breast cancer patients. Due to its epidemiological nature, it cannot answer the question in whom postoperative radiotherapy can be safely omitted. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Single-dose volume regulation algorithm for a gas-compensated intrathecal infusion pump.

    Science.gov (United States)

    Nam, Kyoung Won; Kim, Kwang Gi; Sung, Mun Hyun; Choi, Seong Wook; Kim, Dae Hyun; Jo, Yung Ho

    2011-01-01

    The internal pressures of medication reservoirs of gas-compensated intrathecal medication infusion pumps decrease when medication is discharged, and these discharge-induced pressure drops can decrease the volume of medication discharged. To prevent these reductions, the volumes discharged must be adjusted to maintain the required dosage levels. In this study, the authors developed an automatic control algorithm for an intrathecal infusion pump developed by the Korean National Cancer Center that regulates single-dose volumes. The proposed algorithm estimates the amount of medication remaining and adjusts control parameters automatically to maintain single-dose volumes at predetermined levels. Experimental results demonstrated that the proposed algorithm can regulate mean single-dose volumes with a variation of 98%. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  6. Neurogenesis, Exercise, and Cognitive Late Effects of Pediatric Radiotherapy

    Directory of Open Access Journals (Sweden)

    Shaefali P. Rodgers

    2013-01-01

    Full Text Available Brain cancer is a common type of childhood malignancy, and radiotherapy (RT is a mainstay of treatment. RT is effective for tumor eradication, and survival rates are high. However, RT damages the brain and disrupts ongoing developmental processes, resulting in debilitating cognitive “late” effects that may take years to fully manifest. These late effects likely derive from a long-term decrement in cell proliferation, combined with a neural environment that is hostile to plasticity, both of which are induced by RT. Long-term suppression of cell proliferation deprives the brain of the raw materials needed for optimum cognitive performance (such as new neurons in the hippocampus and new glia in frontal cortex, while chronic inflammation and dearth of trophic substances (such as growth hormone limit neuroplastic potential in existing circuitry. Potential treatments for cognitive late effects should address both of these conditions. Exercise represents one such potential treatment, since it has the capacity to enhance cell proliferation, as well as to promote a neural milieu permissive for plasticity. Here, we review the evidence that cognitive late effects can be traced to RT-induced suppression of cell proliferation and hostile environmental conditions, as well as emerging evidence that exercise may be effective as an independent or adjuvant therapy.

  7. 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.

  8. Effect of radiotherapy on the natural killer (NK)-cell activity of cancer patients

    International Nuclear Information System (INIS)

    McGinnes, K.; Florence, J.; Penny, R.

    1987-01-01

    The aim of this study was to determine the effect of radiotherapy on peripheral blood natural killer (NK)-cell number and activity in 15 patients with cancer, prior to the commencement and at the completion of radiotherapy. The following observations were made. Prior to radiotherapy NK activity could not be correlated with the stage of malignancy. In all patients with advanced disease and with subnormal baseline NK activity, the outcome of radiotherapy was unfavorable. Following radiotherapy to sites including the mediastinum, patients had decreased NK activity compared with those receiving treatment to other sites. This decrease was not related to the dose of radiotherapy or stage of malignancy. The tumor response was favorable in most patients whose NK activity decreased as a result of radiotherapy. The decrease in NK activity may be associated with a decrease in the percentage of NK (N901) cells in the peripheral blood. The reduction in NK activity in those patients receiving mediastinal irradiation may be due to the large volume of blood which transits the field, so that the NK cells, or their more radiosensitive precursors, may be damaged and/or differentiation inhibited. Thus, these new observations show that radiotherapy does indeed affect the NK activity in cancer patients predominantly when the irradiation site includes the mediastinum

  9. Side Effects of Adjuvant Radiotherapy in Patients With Testicular Seminoma Stage I

    International Nuclear Information System (INIS)

    Gamulin, M.; Grgic, M.

    2011-01-01

    In the present study the side effects of adjuvant radiotherapy of testicular seminoma stage I patients were followed up in the period between 13 to 84 months (median 28 months). The most frequent side effects in these patients during radiotherapy were gastrointestinal problems (nausea/vomiting), psychologic and cognitive problems and minor sexual problems. The reported side effects were treated by antimmimetics and anxiolytics. After radiotherapy, the side effects persisted in 6 % of patients but therapy was needed only in few. Healthy children were born to 76 % of patients in the age group 18 - 39 years after radiotherapy. The present study shows that adjuvant irradiation of paraaortal lymph nodes with total a dose of 24 Gy in 16 daily fractions in testicular seminoma patients causes acceptable side effects with acceptable quality of life and fertility, however in conditions of individual approach and family consulting. (author)

  10. Radiobiological considerations of late effects arising from radiotherapy

    International Nuclear Information System (INIS)

    Kogelnik, H.D.; Kaercher, K.H.

    1977-01-01

    A variety of clinical and experimental data are reviewed to investigate the different factors leading to appearance of late complications. Higher individual doses per fraction are related to an increase in the incidence and severity of late effects and massive dose techniques result in catastrophic late complications. There is no apparent relation between the severity of initial skin reactions and late effects, indicating that matching of acute radiation reactions on skin or mucous membranes cannot be extrapolated to late damage in connective tissues and organs. The probability of late tissue injury increases with the volume of tissue irradiated. Several phenomena, e.g. parenchymal cell depletion, vascular injury and fibrocyte dysfunction, are likely to operate together as well as separately in the pathogenesis of late effects. The late complications of radiotherapy develop in cells with a slow proliferation, and this is consistent with the hypothesis that parenchymal cell killing may be the basis for the injury. The response of cells with a slow proliferation to a course of fractionated irradiation differs from that of rapidly proliferative cells in three biological processes: repair of potentially lethal damage, redistribution and regeneration. (author)

  11. Long-term effects of radiotherapy in childhood and adolescence

    International Nuclear Information System (INIS)

    Larson, D.L.; Kroll, S.; Jaffe, N.; Serure, A.; Goepfert, H.

    1990-01-01

    The records of 50 selected pediatric patients who were treated and followed at M. D. Anderson Cancer Center were reviewed to study the late effects of nonsurgical treatment of cancer in children. There were 26 girls and 24 boys ranging in age between 2 months and 16 years. Patients with head and neck cancer received chemotherapy and radiotherapy for rhabdomyosarcoma (n = 27), retinoblastoma (n = 8), or nasopharynx cancer (n = 2). Median follow-up was 13 years. The most severe side effects were noted in the fields of radiation and included hypoplasia of the jaw, orbit, or hemi-face with varying degrees of atrophy of the overlying soft tissues. A wide range of endocrine, dental, and psychologic abnormalities was also documented. Since 1 in every 1,000 adults older than 20 years today is likely to be a survivor of childhood cancer, recommendations are made for this new class of patients whom the head and neck surgeon will be seeing in the future

  12. Effectiveness and problems of radiotherapy for the advanced biliary tract cancer

    International Nuclear Information System (INIS)

    Ueda, Nobuhiko; Konishi, Ichiro; Izumi, Ryohei

    1999-01-01

    To elucidate the effectiveness and problems of radiotherapy for the advanced biliary tract cancer, 19 cases with the biliary tract cancer adding radiotherapy (7 cases with bile duct cancer and 12 cases with gallbladder cancer) were stratified into two groups: 3 cases with microscopically non-curative resection adding radiotherapy (group I) and 16 cases with macroscopically non-curative resection or non-resection adding radiotherapy (group II). In the group I, one case of bile duct cancer has been alive for 8 years and 9 months, and the other case had survived for 1 year and 8 months, and one case of gallbladder cancer has been alive for 2 years and 2 months. Survival periods in 12 of 16 cases of group II were within 1 year. But recanalization of bile duct was recognized in 2 of 4 cases of bile duct cancer with external radiotherapy and 7 of 8 cases of gallbladder cancer with external and/or intraoperative radiotherapy. Moreover, in 5 of 6 cases with biliary stent, patency of billary stent had been kept until death. From the above results, radiotherapy is suggested to be effective on the prognosis in group I, and recanalization of bile duct and patency of biliary stent in group II. (author)

  13. Effect of bleomycin-radiotherapy combination in management of head and neck squamous cell carcinoma

    International Nuclear Information System (INIS)

    Shah, P.M.; Shukla, S.N.; Patel, K.M.; Patel, N.L.; Baboo, H.A.; Patel, D.D.

    1981-01-01

    Twenty-five patients with head and neck squamous cell carcinoma were treated with bleomycin-radiotherapy protocol, 15 mg bleomycin I.V. on alternate days followed by radiation within half an hour. The average total dose of bleomycin was 150 mg. Radiotherapy was given daily. Two patients were lost to follow-up very early in the course of the treatment and were removed from the study for statistical purposes. Thirty-six patients with head and neck squamous cell carcinoma who were treated with radiotherapy alone during the same period were used as controls. The patients were followed for two years. The incidence of response rate did not differ significantly between regimens; however, the incidence of side effects with bleomycin-radiotherapy, 82.61%, is significantly more than that of radiotherapy alone (52.78%). Median survial time (MST) of those responding to bleomycin-radiotherapy protocol was seven months and 12 days and for radiotherapy responders was six months. Neither the response rate nor the MST improve significantly after pretreatment with bleomycin. On the contrary, the incidence of side effects increased significantly

  14. Adaptive radiotherapy in muscle invasive urinary bladder cancer - An effective method to reduce the irradiated bowel volume

    International Nuclear Information System (INIS)

    Tuomikoski, Laura; Collan, Juhani; Keyrilaeinen, Jani; Visapaeae, Harri; Saarilahti, Kauko; Tenhunen, Mikko

    2011-01-01

    Background and purpose: To evaluate the benefits of adaptive radiotherapy for bladder cancer in decreasing irradiation of small bowel. Material and methods: Five patients with muscle invasive bladder cancer received adaptive radiotherapy to a total dose of 55.8-65 Gy with daily cone-beam computed tomography scanning. The whole bladder was treated to 45-50.4 Gy, followed by a partial bladder boost. The plan of the day was chosen from 3 to 4 pre-planned treatment plans according to the visible extent of bladder wall in cone-beam computed tomography images. Dose volume histograms for intestinal cavity volumes were constructed and compared with corresponding histograms calculated for conventional non-adaptive radiotherapy with single treatment plan of 2 cm CTV-PTV margins. CTV dose coverage in adaptive treatment technique was compared with CTV dose coverage in conventional radiotherapy. Results: The average volume of intestinal cavity receiving ≥45 Gy was reduced from 335 ± 106 cm 3 to 180 ± 113 cm 3 (1SD). The maximum volume of intestinal cavity spared at 45 Gy on a single patient was 240 cm 3 , while the minimum volume was 65 cm 3 . The corresponding reduction in average intestinal cavity volume receiving ≥45 Gy calculated for the whole bladder treatment only was 66 ± 36 cm 3 . CTV dose coverage was improved on two out of five patients and decreased on three patients. Conclusions: Adaptive radiotherapy considerably reduces dose to the small bowel, while maintaining the dose coverage of CTV at similar level when compared to the conventional treatment technique.

  15. Effects of fractionated stereotactic radiotherapy for primary hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Choi, Byeong Ock; Jang, Hong Seok; Kang, Young Nam; Choi, Ihl Bhong; Kang, Ki Mun; Chai, Gyu Young; Lee, Sang Wook

    2005-01-01

    Reports on the outcome of curative radiotherapy for the primary hepatocellular carcinoma (HCC) are rarely encountered in the literature. In this study, we report our experience of a clinical trial where fractionated stereotactic radiotherapy (SRT) was used in treating a primary HCC. A retrospective analysis was performed on 20 patients who had been histologically diagnosed as HCC and treated by fractionated SRT. The long diameter of tumor measured by CT was 2 ∼ 6.5 cm (average: 3.8 cm). A single dose of radiation used in fractionated SRT was 5 or 10 Gy; each dose was prescribed based on the planning target volume and normalized to 85 ∼ 99% isocenter dose. Patients were treated 3 ∼ 5 times per week for 2 weeks, with each receiving a total dose of 50 Gy (the median dose: 50 Gy). The follow up period was 3 ∼ 55 months (the median follow up period: 23 months). The response rate was 60% (12 patients), with 4 patients showing complete response (20%), 8 patients showing partial response (40%), and 8 patients showing stable disease (40%). The 1-year and 2-year survival rates were 70.0% and 43.1%, respectively,and the median survival time was 20 months. The 1-year and 2-year disease free survival rates were 65% and 32.5%, respectively, and the median disease-free survival rate was 19 months. Some acute complications of the treatment were noted as follows: dyspepsia in 12 patients (60%), nausea/emesis in 8 patients (40%), and transient liver function impairment in 6 patients (30%). However, there was no treatment related death. The study indicates that fractionated SRT is a relatively safe and effective method for treating primary HCC. Thus, fractionated SRT may be suggested as a local treatment for HCC of small lesion and containing a single lesion, when the patients are inoperable or operation is refused by the patients. We thought that fractionated SRT is a challenging treatment modality for the HCC

  16. Cardiovascular effects of radiotherapy on the patient with cancer

    International Nuclear Information System (INIS)

    Moreira, Leonardo Augusto Robert; Silva, Eduardo Nani; Ribeiro, Mario Luiz; Martins, Wolney de Andrade

    2016-01-01

    The incidence of cancer (CA) has increased globally and radiotherapy (RT) is a vital component in its treatment. Cardiovascular injuries induced by RT in the treatment of thoracic and cervical CA have been causing problems in clinical practice for decades, and are among the most serious adverse effects of radiation experienced by the growing number of cancer survivors. This article presents a review on the Lilacs, Scielo and Pubmed databases of the main cardiovascular injuries, their mechanisms, clinical presentations, treatments and prevention proposals. Injuries caused by RT include diseases of the pericardium, coronary artery disease, valvular disease, myocardial disease with systolic and diastolic dysfunction, conduction disorders, and carotid artery and great vessels disease. Thoracic and cervical irradiation increases cardiovascular morbidity and mortality. Despite the great progress in the improvement of RT techniques, totally excluding prime areas of the cardiovascular system from the irradiation field is not yet possible. Guidelines must be created for monitoring, diagnosis and treatment of patients with CA treated with RT. (author)

  17. Cardiovascular effects of radiotherapy on the patient with cancer

    Directory of Open Access Journals (Sweden)

    Leonardo Augusto Robert Moreira

    2016-04-01

    Full Text Available Summary The incidence of cancer (CA has increased globally and radiotherapy (RT is a vital component in its treatment. Cardiovascular injuries induced by RT in the treatment of thoracic and cervical CA have been causing problems in clinical practice for decades, and are among the most serious adverse effects of radiation experienced by the growing number of cancer survivors. This article presentes a review on the Lilacs, Scielo and Pubmed databases of the main cardiovascular injuries, their mechanisms, clinical presentations, treatments and prevention proposals. Injuries caused by RT include diseases of the pericardium, coronary artery disease, valvular disease, myocardial disease with systolic and diastolic dysfunction, conduction disorders, and carotid artery and great vessels disease. Thoracic and cervical irradiation increases cardiovascular morbidity and mortality. Despite the great progress in the improvement of RT techniques, totally excluding prime areas of the cardiovascular system from the irradiation field is not yet possible. Guidelines must be created for monitoring, diagnosis and treatment of patients with CA treated with RT.

  18. Cardiovascular effects of radiotherapy on the patient with cancer

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Leonardo Augusto Robert; Silva, Eduardo Nani; Ribeiro, Mario Luiz; Martins, Wolney de Andrade, E-mail: wolney_martins@hotmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2016-03-15

    The incidence of cancer (CA) has increased globally and radiotherapy (RT) is a vital component in its treatment. Cardiovascular injuries induced by RT in the treatment of thoracic and cervical CA have been causing problems in clinical practice for decades, and are among the most serious adverse effects of radiation experienced by the growing number of cancer survivors. This article presents a review on the Lilacs, Scielo and Pubmed databases of the main cardiovascular injuries, their mechanisms, clinical presentations, treatments and prevention proposals. Injuries caused by RT include diseases of the pericardium, coronary artery disease, valvular disease, myocardial disease with systolic and diastolic dysfunction, conduction disorders, and carotid artery and great vessels disease. Thoracic and cervical irradiation increases cardiovascular morbidity and mortality. Despite the great progress in the improvement of RT techniques, totally excluding prime areas of the cardiovascular system from the irradiation field is not yet possible. Guidelines must be created for monitoring, diagnosis and treatment of patients with CA treated with RT. (author)

  19. Clinical studies of effect of Jinshi Granule on reducing the toxic radiotherapy reaction in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Jin Hong; Wu Xiangwei

    2002-01-01

    Objective: To study the effects of Jinshi Granule (JSG) on decreasing the toxic reaction of radiotherapy in nasopharyngeal carcinoma (NPC) patients in order to search for an effective method and medicines. Methods: Altogether 90 patients with NPC treated by radical radiotherapy were divided into three groups at random. Each group consisted of 30 patients who all received radiotherapy. Patients of the 1st treatment group were treated by JSG, the 2nd treatment group by Biyan Qingdu Ji (BQJ), and the control group by placebo. Results: (1) In JSG group, the effective rate, the rate of completing radiotherapy, the enhancing and stabilization rate of quality of life were 93.33%, 96.67% and 90.00%, respectively, which were all higher than those in other groups (P < 0.05, P < 0.01). (2) The degree of the toxic reaction syndromes in the JSG group was lower than that in other two groups and the stabilization of peripheral hemogram was much better (P < 0.05, P < 0.01). Conclusion: These data show that JSG has significant effects on reducing the toxic reaction of radiotherapy to NPC and combining it with radiotherapy is an effective method in treating NPC

  20. Hippocampal dose volume histogram predicts Hopkins Verbal Learning Test scores after brain irradiation

    Directory of Open Access Journals (Sweden)

    Catherine Okoukoni, PhD

    2017-10-01

    Full Text Available Purpose: Radiation-induced cognitive decline is relatively common after treatment for primary and metastatic brain tumors; however, identifying dosimetric parameters that are predictive of radiation-induced cognitive decline is difficult due to the heterogeneity of patient characteristics. The memory function is especially susceptible to radiation effects after treatment. The objective of this study is to correlate volumetric radiation doses received by critical neuroanatomic structures to post–radiation therapy (RT memory impairment. Methods and materials: Between 2008 and 2011, 53 patients with primary brain malignancies were treated with conventionally fractionated RT in prospectively accrued clinical trials performed at our institution. Dose-volume histogram analysis was performed for the hippocampus, parahippocampus, amygdala, and fusiform gyrus. Hopkins Verbal Learning Test-Revised scores were obtained at least 6 months after RT. Impairment was defined as an immediate recall score ≤15. For each anatomic region, serial regression was performed to correlate volume receiving a given dose (VD(Gy with memory impairment. Results: Hippocampal V53.4Gy to V60.9Gy significantly predicted post-RT memory impairment (P < .05. Within this range, the hippocampal V55Gy was the most significant predictor (P = .004. Hippocampal V55Gy of 0%, 25%, and 50% was associated with tumor-induced impairment rates of 14.9% (95% confidence interval [CI], 7.2%-28.7%, 45.9% (95% CI, 24.7%-68.6%, and 80.6% (95% CI, 39.2%-96.4%, respectively. Conclusions: The hippocampal V55Gy is a significant predictor for impairment, and a limiting dose below 55 Gy may minimize radiation-induced cognitive impairment.

  1. Hypoxia-targeted suicidal gene therapy system enhances antitumor effects of radiotherapy

    International Nuclear Information System (INIS)

    Liu Junye; Guo Yao; Guo Guozhen

    2006-01-01

    Objective: To explore the effects of hypoxia-targeted suicidal gene therapy system combined with radiotherapy on pancreatic cancer. Methods: The recombinant adenovirus Ad-5HRE/hCMVmp-BCD was constructed by DNA recombinant technique. Western blot was used to detect hypoxia-induced expression of bacterial cytosine deaminase (BCD). Cell growth inhibition assay was used to determine the sensitivity of human pancreatic cancer cells MIA-PACA2 to 5-fluorocytosine (5-FC). Tumor xenograft growth delay assays was used to evaluate the effects of Ad-5HRE/hCMVmp-BCD/5-FC combined with radiotherapy on pancreatic cancer. Results: Western blot analysis demonstrated that hypoxia-induced BCD protein expression was achieved in MIA-PACA2 cells infected with Ad-5HRE/hCMVmp-BCD. With hypoxia treatment, the sensitivity of MIA-PACA2 cells infected with Ad-5HRE/hCMVmp-BCD to 5-FC significantly increased. Administration of either Ad-5HRE/hCMVmp-BCD/5-FC or radiotherapy could inhibit the growth of MIA-PACA2 xenografts in nude mice. Moreover, combination of Ad-5HRE/hCMVmp-BCD/5-FC could significantly enhance suppressing effects of radiotherapy on MIA-PACA2 xenografts. Conclusion: Hypoxia-targeted suicidal gene therapy system Ad-5HRE/hCMVmp-BCD/5-FC could enhance antitumor effects of radiotherapy on pancreatic cancer and can be used as a powerful adjunct to conventional radiotherapy. (authors)

  2. Immunological factors correlated in radiation effect in cancer patients treated by radiotherapy alone or radiotherapy with combined chemotherapy

    International Nuclear Information System (INIS)

    Kimura, Shuji

    1981-01-01

    Local immunological factors are thought to be parenchymal reaction of normal and tumor tissues. Those were studied by morphological changes of angiographic findings and histological methods which included photomicroscopic, electromicroscopic and enzymic-histochemical studies. It was demonstrated that the effect of radiotherapy depended on not only local blood supply but also parenchymal reaction of the host. Especially, the parenchymal reaction at 2000 or 3000 rad irradiation was regarded as nonspecific tissue repair as well as immunological protective reactions brought about by enhancement of the tumor antigenicity. It was proved that T-cell system played a main role in this parenchymal reaction. Changes of systemic immunological factors were studied in 17 laryngeal cancer and 80 lung cancer patients treated by radiotherapy alone or radiotherapy with combined chemotherapy. Due to the fact that damages of the host before treatment were not so serious and integral dose given to the patients was a little in cases of laryngeal cancer immunological parameters such as absolute lymphocyte counts, PHA and PPD skin test activities, lymphocyte blastoid transformation with PHA, PWM and Con A, did not show significant change. However, as for lung cancer treated by large integral dose irradiation combined with chemotherapy, immunological parameters were depressed in inverse proportion to the dose of irradiation and chemotherapeutic agents. Moreover T-cell subsets (early E-rosette forming cells, IgG Fc-receptor positive cells), lymphocyte sub-populations, ADCC activity, serum immunoglobulins, and serum protein were also investigated in cases of lung cancer. We have evaluated the immunological parameters in relation to the therapeutic effect. As a result, it was suggested that several parameters should be needed to forecast the prognosis. (author)

  3. Lung and heart dose volume analyses with CT simulator in tangential field irradiation of breast cancer

    International Nuclear Information System (INIS)

    Das, Indra J.; Cheng, Elizabeth C.; Fowble, Barbara

    1997-01-01

    Objective: Radiation pneumonitis and cardiac effects are directly related to the irradiated lung and heart volumes in the treatment fields. The central lung distance (CLD) from a tangential breast radiograph is shown to be a significant indicator of ipsilateral irradiated lung volume based on empirically derived functions which accuracy depends on the actual measured volume in treatment position. A simple and accurate linear relationship with CLD and retrospective analysis of the pattern of dose volume of lung and heart is presented with actual volume data from a CT simulator in the treatment of breast cancer. Materials and Methods: The heart and lung volumes in the tangential treatment fields were analyzed in 45 consecutive (22 left and 23 right breast) patients referred for CT simulation of the cone down treatment. All patients in this study were immobilized and placed on an inclined breast board in actual treatment setup. Both arms were stretched over head uniformly to avoid collision with the scanner aperture. Radiopaque marks were placed on the medial and lateral borders of the tangential fields. All patients were scanned in spiral mode with slice width and thickness of 3 mm each, respectively. The lung and heart structures as well as irradiated areas were delineated on each slice and respective volumes were accurately measured. The treatment beam parameters were recorded and the digitally reconstructed radiographs (DRRs) were generated for the CLD and analysis. Results: Table 1 shows the volume statistics of patients in this study. There is a large variation in the lung and heart volumes among patients. Due to differences in the shape of right and left lungs the percent irradiated volume (PIV) are different. The PIV data have shown to correlate with CLD with 2nd and 3rd degree polynomials; however, in this study a simple straight line regression is used to provide better confidence than the higher order polynomial. The regression lines for the left and right

  4. Lung and heart dose volume analyses with CT simulator in radiation treatment of breast cancer

    International Nuclear Information System (INIS)

    Das, Indra J.; Cheng, Elizabeth C.; Freedman, Gary; Fowble, Barbara

    1998-01-01

    Purpose: Radiation pneumonitis and cardiac effects are directly related to the irradiated lung and heart volumes in the treatment fields. The central lung distance (CLD) from a tangential breast radiograph is shown to be a significant indicator of ipsilateral irradiated lung volume. Retrospective analysis of the pattern of dose volume of lung and heart with actual volume data from a CT simulator in the treatment of breast cancer is presented with respect to CLD. Methods and Materials: The heart and lung volumes in the tangential treatment fields were analyzed in 108 consecutive cases (52 left and 56 right breast) referred for CT simulation. All patients in this study were immobilized and placed on an inclined breast board in actual treatment setup. Both arms were stretched over head to avoid collision with the scanner aperture. Radiopaque marks were placed on the medial and lateral borders of the tangential fields. All patients were scanned in spiral mode with slice width and thickness of 3 mm each, respectively. The lung and heart structures as well as irradiated areas were delineated on each slice and respective volumes were accurately measured. The treatment beam parameters were recorded and the digitally reconstructed radiographs (DRRs) were generated for the measurement of the CLD and analysis. Results: Using CT data the mean volume and standard deviation of left and right lungs were 1307.7 ± 297.7 cm 3 and 1529.6 ± 298.5 cm 3 , respectively. The magnitude of irradiated volume in left and right lung is nearly equal for the same CLD that produces different percent irradiated volumes (PIV). The left and right PIV lungs are 8.3 ± 4.7% and 6.6 ± 3.7%, respectively. The PIV data have shown to correlate with CLD with second- and third-degree polynomials; however, in this study a simple straight line regression is used to provide better confidence than the higher order polynomials. The regression lines for the left and right breasts are very different based on

  5. Evaluation of dose-volume histograms after prostate seed implantation. 4-year experience

    International Nuclear Information System (INIS)

    Hoinkis, C.; Lehmann, D.; Winkler, C.; Herrmann, T.; Hakenberg, O.W.; Wirth, M.P.

    2004-01-01

    Background and purpose: permanent interstitial brachytherapy by seed implantation is a treatment alternative for low-volume low-risk prostate cancer and a complex interdisciplinary treatment with a learning curve. Dose-volume histograms are used to assess postimplant quality. The authors evaluated their learning curve based on dose-volume histograms and analyzed factors influencing implantation quality. Patients and methods: since 1999, 38 patients with a minimum follow-up of 6 months were treated at the authors' institution with seed implantation using palladium-103 or iodine-125, initially using the preplan method and later real-time planning. Postimplant CT was performed after 4 weeks. The dose-volume indices D90, V100, V150, the D max of pre- and postplans, and the size and position of the volume receiving the prescribed dose (high-dose volume) of the postplans were evaluated. In six patients, postplan imaging both by CT and MRI was used and prostate volumes were compared with preimplant transrectal ultrasound volumes. The first five patients were treated under external supervision. Results: patients were divided into three consecutive groups for analysis of the learning curve (group 1: n = 5 patients treated under external supervision; group 2: n = 13 patients; group 3: n = 20 patients). D90 post for the three groups were 79.3%, 74.2%, and 99.9%, the V100 post were 78.6%, 73.5%, and 88.2%, respectively. The relationship between high-dose volume and prostate volume showed a similar increase as the D90, while the relationship between high-dose volume lying outside the prostate and prostate volume remained constant. The ratio between prostate volumes from transrectal ultrasound and CT imaging decreased with increasing D90 post , while the preplanning D90 and V100 remained constant. The different isotopes used, the method of planning, and the implanted activity per prostate volume did not influence results. Conclusion: a learning curve characterized by an increase

  6. Radiotherapy - an effective treatment for vaginal verrucous carcinoma

    International Nuclear Information System (INIS)

    Reinecke, L.; Thornley, A.L.

    1993-01-01

    Vaginal carcinoma makes up 1%-2% of all gynaecological tumours. Verrucous carcinoma of the vagina is even more rare -only 16 cases are reported in the scientific literature. A case of a complete regression after 60 Gy fractionated radiotherapy by a tumour 12 cm 3 in size is reported. Most authors are of the opinion that radiotherapy causes anaplastic transformation of verrucous carcinoma. The minority view, that anaplastic transformation does not occur, is correct and is supported by our clinical and radiological data. The conflicting literature on vaginal verrucous carcinoma (VVC) is reviewed with reference to verrucous carcinoma at other sites. (Author)

  7. Relationship between radiation dose and lung function in patients with lung cancer receiving radiotherapy

    International Nuclear Information System (INIS)

    Harsaker, V.; Dale, E.; Bruland, O.S.; Olsen, D.R.

    2003-01-01

    In patients with inoperable non-small cell lung cancer (NSCLC), radical radiotherapy is the treatment of choice. The dose is limited by consequential pneumonitis and lung fibrosis. Hence, a better understanding of the relationship between the dose-volume distributions and normal tissue side effects is needed. CT is a non-invasive method to monitor the development of fibrosis and pneumonitis, and spirometry is an established tool to measure lung function. NSCLC patients were included in a multicenter trial and treated with megavoltage conformal radiotherapy. In a subgroup comprising 16 patients, a total dose of 59-63 Gy with 1.8-1.9 Gy per fraction was given. Dose-volume histograms were calculated and corrected according to the linear-quadratic formula using alpha/beta=3 Gy. The patients underwent repetitive CT examinations (mean follow-up, 133 days) following radiotherapy, and pre and post treatment spirometry (mean follow-up, 240 days). A significant correlation was demonstrated between local lung dose and changes in CT numbers >30 days after treatment (p 40 Gy Gy there was a sudden increase in CT numbers at 70-90 days. Somewhat unexpectedly, the highest mean lung doses were found in patients with the least reductions in lung function (peak expiratory flow; p<0.001). The correlation between CT numbers, radiation dose and time after treatment show that CT may be used to monitor development of lung fibrosis/pneumonitis after radiotherapy for lung cancer. Paradoxically, the patients with the highest mean lung doses experienced the minimum deterioration of lung function. This may be explained by reduction in the volume of existing tumour masses obstructing the airways, leading to relief of symptoms. This finding stresses the role of radiotherapy for lung cancer, especially where the treatment aim is palliative

  8. A case showing effective radiotherapy for a radiation-induced glioblastoma

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    Fukui, Kimiko; Inamura, Takanori; Nakamizo, Akira; Ikezaki, Kiyonobu; Inoha, Satoshi; Nakamura, Kazumasa; Matsuzaki, Akinobu; Fukui, Masashi [Kyushu Univ., Fukuoka (Japan). Graduate School of Medical Sciences

    2001-07-01

    Radiation-induced glioblastoma is usually resistant to all treatments. We report a case with radiation-induced glioblastoma, in which radiotherapy was remarkably effective. A 14-year-old female with a history of acute lymphoblastic leukemia, at the age of 7, underwent 15 Gy of radiotherapy to the whole brain. She was admitted to our department due to the development of headache and nausea. Magnetic resonance imaging showed an irregularly enhanced mass in the left frontal lobe. Partial removal of the mass was performed and histological examination showed it to be glioblastoma with a high MIB-1 index. The patient underwent 40 Gy of local radiotherapy and chemotherapy with ACNU and Interferon-{beta} for 2 years. The residual tumor disappeared after the radiotherapy, and her status is still ''complete remission'', 29 months after the onset. (author)

  9. Effect of radiotherapy on lymphocyte cytotoxicity against allogeneic lung cancer cells in patients with bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Toyohira, Ken; Yasumoto, Kosei; Manabe, Hideo; Ohta, Mitsuo; Terashima, Hiromi

    1979-01-01

    Cytotoxicity of peripheral blood lymphocytes against allogeneic target cells of bronchogenic carcinoma was examined by a microcytotoxicity test before, during, and after radiotherapy in primary lung cancer patients. Before the treatment, cytotoxicity was depressed only slightly in patients in stage III and strikingly in those in stage IV, as compared to the values in patients at earlier stages of lung cancer such as stages I and II. Local irradiation scarcely affected cytotoxicity at stages II and III, but augmented remarkably at stage IV. The number of peripheral blood lymphocytes decreased profoundly during and after radiotherapy in all cases of stages II, III, and IV. Although radiotherapy exhibited various effects on the cytotoxic activity of lymphocytes and the number of peripheral blood lymphocytes, only the cytotoxic activity at the end of radiotherapy correlated well with the reduction in tumor size. (author)

  10. Late temporal lobe necrosis after conventional radiotherapy for carcinoma of maxillary sinus.

    Science.gov (United States)

    Kanakamedala, Madhava R; Mahta, Ali; Liu, Jianlin; Kesari, Santosh

    2012-12-01

    Cerebral radiation necrosis is a serious late complication after conventional radiotherapy that can present with focal neurologic deficits or with more generalized signs and symptoms of increased intracranial pressure, depending on the location. The incidence and severity of radionecrosis are dose-volume dependent. We report a case of cerebral radiation necrosis 5 years after radiotherapy for a maxillary sinus carcinoma.

  11. Tumor dose-volume response in image-guided adaptive brachytherapy for cervical cancer: A meta-regression analysis.

    Science.gov (United States)

    Mazeron, Renaud; Castelnau-Marchand, Pauline; Escande, Alexandre; Rivin Del Campo, Eleonor; Maroun, Pierre; Lefkopoulos, Dimitri; Chargari, Cyrus; Haie-Meder, Christine

    2016-01-01

    Image-guided adaptive brachytherapy is a high precision technique that allows dose escalation and adaptation to tumor response. Two monocentric studies reported continuous dose-volume response relationships, however, burdened by large confidence intervals. The aim was to refine these estimations by performing a meta-regression analysis based on published series. Eligibility was limited to series reporting dosimetric parameters according to the Groupe Européen de Curiethérapie-European SocieTy for Radiation Oncology recommendations. The local control rates reported at 2-3 years were confronted to the mean D90 clinical target volume (CTV) in 2-Gy equivalent using the probit model. The impact of each series on the relationships was pondered according to the number of patients reported. An exhaustive literature search retrieved 13 series reporting on 1299 patients. D90 high-risk CTV ranged from 70.9 to 93.1 Gy. The probit model showed a significant correlation between the D90 and the probability of achieving local control (p < 0.0001). The D90 associated to a 90% probability of achieving local control was 81.4 Gy (78.3-83.8 Gy). The planning aim of 90 Gy corresponded to a 95.0% probability (92.8-96.3%). For the intermediate-risk CTV, less data were available, with 873 patients from eight institutions. Reported mean D90 intermediate-risk CTV ranged from 61.7 to 69.1 Gy. A significant dose-volume effect was observed (p = 0.009). The D90 of 60 Gy was associated to a 79.4% (60.2-86.0%) local control probability. Based on published data from a high number of patients, significant dose-volume effect relationships were confirmed and refined between the D90 of both CTV and the probability of achieving local control. Further studies based on individual data are required to develop nomograms including nondosimetric prognostic criteria. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Estimating dose painting effects in radiotherapy: a mathematical model.

    Directory of Open Access Journals (Sweden)

    Juan Carlos López Alfonso

    Full Text Available Tumor heterogeneity is widely considered to be a determinant factor in tumor progression and in particular in its recurrence after therapy. Unfortunately, current medical techniques are unable to deduce clinically relevant information about tumor heterogeneity by means of non-invasive methods. As a consequence, when radiotherapy is used as a treatment of choice, radiation dosimetries are prescribed under the assumption that the malignancy targeted is of a homogeneous nature. In this work we discuss the effects of different radiation dose distributions on heterogeneous tumors by means of an individual cell-based model. To that end, a case is considered where two tumor cell phenotypes are present, which we assume to strongly differ in their respective cell cycle duration and radiosensitivity properties. We show herein that, as a result of such differences, the spatial distribution of the corresponding phenotypes, whence the resulting tumor heterogeneity can be predicted as growth proceeds. In particular, we show that if we start from a situation where a majority of ordinary cancer cells (CCs and a minority of cancer stem cells (CSCs are randomly distributed, and we assume that the length of CSC cycle is significantly longer than that of CCs, then CSCs become concentrated at an inner region as tumor grows. As a consequence we obtain that if CSCs are assumed to be more resistant to radiation than CCs, heterogeneous dosimetries can be selected to enhance tumor control by boosting radiation in the region occupied by the more radioresistant tumor cell phenotype. It is also shown that, when compared with homogeneous dose distributions as those being currently delivered in clinical practice, such heterogeneous radiation dosimetries fare always better than their homogeneous counterparts. Finally, limitations to our assumptions and their resulting clinical implications will be discussed.

  13. Evaluation of the palliative effect of radiotherapy for esophageal carcinoma

    International Nuclear Information System (INIS)

    Albertsson, M.; Ewers, S.B.; Widmark, H.; Hambraeus, G.; Lillo-Gil, R.; Ranstam, J.; Lund Univ. Hospital

    1989-01-01

    149 patients with carcinoma of the esophagus treated with radiotherapy were evaluated. Eighty-one patients had treatment with palliative intent and 68 with curative intent. The 4-year actuarial survival was 1 and 5% respectively. The tumor size, Karnofsky index (KI) and radiation dose were prognostic factors. The duration of palliation of the patients dysphagia was dose-dependant. (orig.)

  14. Spinocellular carcinoma of the lip, effects of radiotherapy

    International Nuclear Information System (INIS)

    Hess, U.

    1979-01-01

    109 cases of spinocellular carcinoma of the lip were studied with a view to sex dependence, occupation, family disposition and colour of the skin, eyes and hair. Etiology, clinical aspects and course of lip carcinoma were studied. The results obtained with radiotherapy (X-ray therapy) are described and discussed. (APR) [de

  15. The dose-volume constraint satisfaction problem for inverse treatment planning with field segments

    International Nuclear Information System (INIS)

    Michalski, Darek; Xiao, Ying; Censor, Yair; Galvin, James M

    2004-01-01

    The prescribed goals of radiation treatment planning are often expressed in terms of dose-volume constraints. We present a novel formulation of a dose-volume constraint satisfaction search for the discretized radiation therapy model. This approach does not rely on any explicit cost function. Inverse treatment planning uses the aperture-based approach with predefined, according to geometric rules, segmental fields. The solver utilizes the simultaneous version of the cyclic subgradient projection algorithm. This is a deterministic iterative method designed for solving the convex feasibility problems. A prescription is expressed with the set of inequalities imposed on the dose at the voxel resolution. Additional constraint functions control the compliance with selected points of the expected cumulative dose-volume histograms. The performance of this method is tested on prostate and head-and-neck cases. The relationships with other models and algorithms of similar conceptual origin are discussed. The demonstrated advantages of the method are: the equivalence of the algorithmic and prescription parameters, the intuitive setup of free parameters, and the improved speed of the method as compared to similar iterative as well as other techniques. The technique reported here will deliver approximate solutions for inconsistent prescriptions

  16. Effect of image-guided hypofractionated stereotactic radiotherapy on peripheral non-small-cell lung cancer

    Directory of Open Access Journals (Sweden)

    Wang SW

    2016-08-01

    Full Text Available Shu-wen Wang,1 Juan Ren,1 Yan-li Yan,2 Chao-fan Xue,2 Li Tan,2 Xiao-wei Ma2 1Department of Radiotherapy, First Affiliated Hospital of Xian Jiaotong University, 2Medical School of Xian Jiaotong University, Xi’an, Shaanxi, People’s Republic of China Abstract: The objective of this study was to compare the effects of image-guided hypofractionated radiotherapy and conventional fractionated radiotherapy on non-small-cell lung cancer (NSCLC. Fifty stage- and age-matched cases with NSCLC were randomly divided into two groups (A and B. There were 23 cases in group A and 27 cases in group B. Image-guided radiotherapy (IGRT and stereotactic radiotherapy were conjugately applied to the patients in group A. Group A patients underwent hypofractionated radiotherapy (6–8 Gy/time three times per week, with a total dose of 64–66 Gy; group B received conventional fractionated radiotherapy, with a total dose of 68–70 Gy five times per week. In group A, 1-year and 2-year local failure survival rate and 1-year local failure-free survival rate were significantly higher than in group B (P<0.05. The local failure rate (P<0.05 and distant metastasis rate (P>0.05 were lower in group A than in group B. The overall survival rate of group A was significantly higher than that of group B (P=0.03, and the survival rate at 1 year was 87% vs 63%, (P<0.05. The median survival time of group A was longer than that of group B. There was no significant difference in the incidence of complications between the two groups (P>0.05. Compared with conventional fractionated radiation therapy, image-guided hypofractionated stereotactic radiotherapy in NSCLC received better treatment efficacy and showed good tolerability. Keywords: non-small-cell lung cancer, hypofractionated radiotherapy, stereotactic radiotherapy, segmentation, intensity-modulated radiotherapy, image-guided radiation therapy technology

  17. Long-term effects in children treated with radiotherapy for head and neck rhabdomyosarcoma

    International Nuclear Information System (INIS)

    Paulino, Arnold C.; Simon, James H.; Zhen Weining; Wen, B.-C.

    2000-01-01

    Purpose: To examine the long-term effects of treatment in children receiving radiotherapy for head and neck rhabdomyosarcoma. Methods: From 1967 to 1994, a total of 30 children with head and neck rhabdomyosarcoma received megavoltage radiotherapy at one institution. Seventeen patients (57%) have survived and have at least a 5-year follow-up. There were 11 males and 6 females, with a median age of 5.7 years (range 2.2-11.6) at the time of radiotherapy. Tumor location was orbit in 6 patients, infratemporal fossa in 4, paranasal sinuses in 2, and supraglottic larynx in 2; the nasopharynx, pterygopalatine fossa, and parotid gland were sites for the remaining children. All but 2 patients had tumors of embryonal histology. The Intergroup Rhabdomyosarcoma Study (IRS) Group was I in 2, II in 3, and III in 11 children; 1 patient had a recurrent tumor after surgery alone. Radiotherapy volume was the primary tumor or tumor bed in 13, tumor and whole brain in 3, and tumor and craniospinal axis in 1. Median radiotherapy dose to the primary site was 5,040 cGy (range 4,140-6,500) and to the whole brain was 3,000 cGy. All but 1 were treated with 150-200-cGy fractions; 1 patient received 250-cGy fractions for a tumor in the larynx. Chemotherapy was vincristine (V), actinomycin-D (A), and cyclophosphamide (C) in 10 patients, VAC + adriamycin in 2, VA in 1, VA + ifosfamide in 1, VC + adriamycin in 1, and none in 2. One patient had salvage chemotherapy consisting of cisplatin and etoposide. Median follow-up time was 20 years (range 7.5-33). Results: Late effects of treatment were seen in all patients and included facial growth retardation in 11, neuroendocrine dysfunction in 9, visual/orbital problems in 9, dental abnormalities in 7, hearing loss in 6, and hypothyroidism in 3. Intellectual and academic delays were documented in 3 patients who had received whole brain radiotherapy. While neuroendocrine, thyroid, dental, and cognitive sequelae were primarily attributed to radiotherapy

  18. IMRT: Improvement in treatment planning efficiency using NTCP calculation independent of the dose-volume-histogram

    International Nuclear Information System (INIS)

    Grigorov, Grigor N.; Chow, James C.L.; Grigorov, Lenko; Jiang, Runqing; Barnett, Rob B.

    2006-01-01

    The normal tissue complication probability (NTCP) is a predictor of radiobiological effect for organs at risk (OAR). The calculation of the NTCP is based on the dose-volume-histogram (DVH) which is generated by the treatment planning system after calculation of the 3D dose distribution. Including the NTCP in the objective function for intensity modulated radiation therapy (IMRT) plan optimization would make the planning more effective in reducing the postradiation effects. However, doing so would lengthen the total planning time. The purpose of this work is to establish a method for NTCP determination, independent of a DVH calculation, as a quality assurance check and also as a mean of improving the treatment planning efficiency. In the study, the CTs of ten randomly selected prostate patients were used. IMRT optimization was performed with a PINNACLE3 V 6.2b planning system, using planning target volume (PTV) with margins in the range of 2 to 10 mm. The DVH control points of the PTV and OAR were adapted from the prescriptions of Radiation Therapy Oncology Group protocol P-0126 for an escalated prescribed dose of 82 Gy. This paper presents a new model for the determination of the rectal NTCP ( R NTCP). The method uses a special function, named GVN (from Gy, Volume, NTCP), which describes the R NTCP if 1 cm 3 of the volume of intersection of the PTV and rectum (R int ) is irradiated uniformly by a dose of 1 Gy. The function was 'geometrically' normalized using a prostate-prostate ratio (PPR) of the patients' prostates. A correction of the R NTCP for different prescribed doses, ranging from 70 to 82 Gy, was employed in our model. The argument of the normalized function is the R int , and parameters are the prescribed dose, prostate volume, PTV margin, and PPR. The R NTCPs of another group of patients were calculated by the new method and the resulting difference was <±5% in comparison to the NTCP calculated by the PINNACLE3 software where Kutcher's dose

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2018-03-15

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

  20. Principal Component Analysis-Based Pattern Analysis of Dose-Volume Histograms and Influence on Rectal Toxicity

    International Nuclear Information System (INIS)

    Soehn, Matthias; Alber, Markus; Yan Di

    2007-01-01

    Purpose: The variability of dose-volume histogram (DVH) shapes in a patient population can be quantified using principal component analysis (PCA). We applied this to rectal DVHs of prostate cancer patients and investigated the correlation of the PCA parameters with late bleeding. Methods and Materials: PCA was applied to the rectal wall DVHs of 262 patients, who had been treated with a four-field box, conformal adaptive radiotherapy technique. The correlated changes in the DVH pattern were revealed as 'eigenmodes,' which were ordered by their importance to represent data set variability. Each DVH is uniquely characterized by its principal components (PCs). The correlation of the first three PCs and chronic rectal bleeding of Grade 2 or greater was investigated with uni- and multivariate logistic regression analyses. Results: Rectal wall DVHs in four-field conformal RT can primarily be represented by the first two or three PCs, which describe ∼94% or 96% of the DVH shape variability, respectively. The first eigenmode models the total irradiated rectal volume; thus, PC1 correlates to the mean dose. Mode 2 describes the interpatient differences of the relative rectal volume in the two- or four-field overlap region. Mode 3 reveals correlations of volumes with intermediate doses (∼40-45 Gy) and volumes with doses >70 Gy; thus, PC3 is associated with the maximal dose. According to univariate logistic regression analysis, only PC2 correlated significantly with toxicity. However, multivariate logistic regression analysis with the first two or three PCs revealed an increased probability of bleeding for DVHs with more than one large PC. Conclusions: PCA can reveal the correlation structure of DVHs for a patient population as imposed by the treatment technique and provide information about its relationship to toxicity. It proves useful for augmenting normal tissue complication probability modeling approaches

  1. Radiotherapy effect in conservation treatment for breast cancer

    International Nuclear Information System (INIS)

    Sachini, V.; Ferreri, A.J.M.; Farante, G.; Agresti, R.; Galimberti, V.; Zurrida, S.; Veronesi, P.

    1994-01-01

    Radiotherapy (RT) in conservative treatment for breast cancer (CT-BC) has been proven to be determinant for the local control of the disease. Radiation therapy was described by several authors as the most important factor affecting the cosmetic results of this treatment. Technical progress in RT, use of filters and wedges and an increased knowledge of the influence of fraction size total dose and irradiated volume on breast tissues contributed to avoid major radiotherapeutic side effects in the CT-BC. Cosmetic outcome from 2 groups of patients (pts) with breast cancer in stage T 1-2(T> = 2,5 cm) N 0-1 M o0 of the prospective trial Milan III were compared. Both groups pts (n=89) were treated with quadrantectomyand axillary dissection. 49 pts received complementary RT with a dose of 50 Gy over 5 weeks with a daily fraction of 2 Gy and a further boost of 10 Gy (10 MeV electrons) on the scar. Remaining 40 pts did not receive RT. Cosmetic results were subjectively and objectively (asymmetry index) evaluated. No significant cosmetic differences were observed between the 2 study groups. A good or excellent symmetry was observed in 59% of irradiated pts and 64% of non irradiated pts. Negative results were observed in 4% and 2% respectively. Subjective ovulation showed similar results, with a good or excellent symmetry in 57% of irradiated pts and 72.5% of non irradiated pts. Poor results were observed in 16.3% and 27.5% respectively. Telangiectasia were observed in 4% of irradiated pts, while hypertrophied scars were only noted in non irradiated pts (15%). No acute side effects of RT, as erythema or ulceration of breast skin, were recorded. In our experience, the standard dose of 50 Gy administered by two opposite tangential fields plus a 10 Gy boost did not affect the cosmetic results of CT.BC, whereas it provided a better local control of disease. The possibility to avoid RT in selected group of pts should be justified by the discomfort of this treatment for the pt, cost

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

    International Nuclear Information System (INIS)

    Izmajlowicz, B.; Komafel, J.

    2010-01-01

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

  3. Effects of intensity-modulated radiotherapy on human oral microflora

    International Nuclear Information System (INIS)

    Shao Ziyang; Tang Zisheng; Jiang Yuntao; Ma Rui; Liu Zheng; Huang Zhengwei; Yan Chao

    2011-01-01

    This study aimed to evaluate changes in the biodiversity of the oral microflora of patients with head and neck cancer treated with postoperative intensity-modulated radiotherapy (IMRT) or conventional radiotherapy (CRT). Pooled dental plaque samples were collected during the radiation treatment from patients receiving IMRT (n=13) and CRT (n=12). Denaturing gradient gel electrophoresis (DGGE) was used to analyze the temporal variation of these plaque samples. The stimulated and unstimulated salivary flow rates were also compared between IMRT and CRT patients. Reductions in the severity of hyposalivation were observed in IMRT patients compared with CRT patients. We also observed that the temporal stability of the oral ecosystem was significantly higher in the IMRT group (69.96±7.82%) than in the CRT group (51.98±10.45%) (P<0.05). The findings of the present study suggest that IMRT is more conducive to maintaining the relative stability of the oral ecosystem than CRT. (author)

  4. Effect of radiotherapy on lymphocyte cytotoxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, J; Melen, B [Central Microbiological Laboratory, Stockholm County Council (Sweden); Blomgren, H; Glas, U; Perlmann, P

    1975-11-01

    The cytotoxic functions of highly purified blood lymphocytes from patients with breast cancer were studied before and after radiotherapy. Addition of PHA or of rabbit antibodies to target cells (chicken erythrocytes) were chosen as two means of inducing lymphocyte cytotoxicity in vitro. The proportion of T and non-T lymphocytes was determined by means of E and EAC rosette tests. The antibody-induced cytotoxicity of lymphocytes decreased following radiotherapy while that mediated by PHA remained unchanged. There was some reduction in the percentage of EAC rosette-forming cells. These results, as well as earlier observations, suggest that the decrease in the peripheral blood of the proportion of lymphocytes with receptors for activated complement is responsible for changes in the antibody-mediated lymphocyte cytotoxicity.

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

    International Nuclear Information System (INIS)

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

    2011-01-01

    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.

  6. Radiotherapy for cancer patients aged 80 and older: a study of effectiveness and side effects

    International Nuclear Information System (INIS)

    Zachariah, Babu; Balducci, Lodovico; Venkattaramanabalaji, G.V.; Casey, Linda; Greenberg, Harvey M.; Del Regato, Juan A.

    1997-01-01

    Purpose: To profile cancer patients aged 80 and older undergoing radiotherapy and to study the tumor response and side effects of therapy. Methods and Materials: We retrospectively analyzed the records of patients aged 80 and older who received radiation therapy at James A. Haley Veterans Hospital and H. Lee Moffitt Cancer Center between 1988 and 1995. A total of 203 patients aged 80-94 received radiotherapy during this period. Treatment sites included head and neck [50], breast [16], chest [37], pelvis [53], and miscellaneous [39]. Age, treatment site, field size, total dose, response to treatment, treatment interruptions, incidence and severity of weight loss, myelosuppression, diarrhea, mucositis, dermatitis, and follow-up status are assessed using our departmental records and hospital tumor registry. Results: Of 191 patients evaluated, 179 (94%) completed the treatment without serious complications. A total of 195 sites were irradiated. Twelve patients (6%) required interruption of the treatment. Therapeutic responses were seen in 86 out of 112 patients (77%) treated with curative intent (with 67% complete response) and in 67 out of 83 patients (81%) treated with palliative intent. The causes of treatment interruptions included weight loss from diarrhea, dysphagia, and progressive disease. Treatment interruptions were more likely in patients treated with large treatment fields. In patients treated for upper aero-digestive tract cancer, Grade 3 and 4 mucositis was noted in 20 and 2% of patients, respectively. Grade 1 and 2 enteritis was noted in 43% of patients treated for pelvic malignancies. Grade 3 dermatitis was noted only in 2% of patients. Conclusion: Radiotherapy is highly effective and well tolerated by the oldest old. Age is not a contraindication to aggressive radiotherapy

  7. Quantitative Ultrasound Characterization of Cancer Radiotherapy Effects In Vitro

    International Nuclear Information System (INIS)

    Vlad, Roxana M.; Alajez, Nehad M.; Giles, Anoja B.Sc.; Kolios, Michael C.; Czarnota, Gregory J.

    2008-01-01

    Purpose: Currently, no routinely used imaging modality is available to assess tumor responses to cancer treatment within hours to days after radiotherapy. In this study, we demonstrate the preclinical application of quantitative ultrasound methods to characterize the cellular responses to cancer radiotherapy in vitro. Methods and Materials: Three different cell lines were exposed to radiation doses of 2-8 Gy. Data were collected with an ultrasound scanner using frequencies of 10-30 MHz. As indicators of response, ultrasound integrated backscatter and spectral slope were determined from the cell samples. These parameters were corrected for ultrasonic attenuation by measuring the attenuation coefficient. Results: A significant increase in the ultrasound integrated backscatter of 4-7 dB (p < 0.001) was found for radiation-treated cells compared with viable cells at all radiation doses. The spectral slopes decreased in the cell samples that predominantly underwent mitotic arrest/catastrophe after radiotherapy, consistent with an increase in cell size. In contrast, the spectral slopes did not change significantly in the cell samples that underwent a mix of cell death (apoptosis and mitotic arrest), with no significant change in average cell size. Conclusion: The changes in ultrasound integrated backscatter and spectral slope were direct consequences of cell and nuclear morphologic changes associated with cell death. The results indicate that this combination of quantitative ultrasonic parameters has the potential to assess the cell responses to radiation, differentiate between different types of cell death, and provide a preclinical framework to monitor tumor responses in vivo

  8. Evaluation of clinical hypothyroidism risk due to irradiation of thyroid and pituitary glands in radiotherapy of nasopharyngeal cancer patients

    International Nuclear Information System (INIS)

    Lin, Zhixiong; Wang, Xiaoyan; Xie, Wenjia; Che, Kaijun; Wu, Vincent W.C.

    2013-01-01

    Radiation-induced thyroid dysfunction after radiotherapy for nasopharyngeal cancer (NPC) has been reported. This study investigated the radiation effects of the thyroid and pituitary glands on thyroid function after radiotherapy for NPC. Sixty-five NPC patients treated with radiotherapy were recruited. Baseline thyroid hormone levels comprising free triiodothyronine (fT3), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) were taken before treatment and at 3, 6, 12 and 18 months. A seven-beam intensity-modulated radiotherapy plan was generated for each patient. Thyroid and pituitary gland dose volume histograms were generated, dividing the patients into four groups: high (>50Gy) thyroid and pituitary doses (HTHP group); high thyroid and low pituitary doses (HTLP group); low thyroid and high pituitary doses; and low thyroid and pituitary doses. Incidence of hypothyroidism was analysed. Twenty-two (34%) and 17 patients (26%) received high mean thyroid and pituitary doses, respectively. At 18 months, 23.1% of patients manifested various types of hypothyroidism. The HTHP group showed the highest incidence (83.3%) of hypothyroidism, followed by the HTLP group (50%). NPC patients with high thyroid and pituitary gland doses carried the highest risk of abnormal thyroid physiology. The dose to the thyroid was more influential than the pituitary dose at 18 months after radiotherapy, and therefore more attention should be given to the thyroid gland in radiotherapy planning.

  9. Severe side effects with the application of Mesalazine (5-aminosalicylic acid) during radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Freund, U.; Siems, H.; Wannenmacher, M.; Schoelmerich, J.; Kluge, F.; Schaefer, H.E.

    1987-10-01

    In a prospective randomized placebo controlled double blind study, the prophylactic effect of Mesalazine (5-aminosalicylic acid, 5-ASA) as suppositories (3x250 mg/day) on radiation induced proctitis during radiotherapy for prostatic carcinoma was studied. The study ended when 16 patients had been included (5-ASA: Eight, placebo: Eight) because of severe side effects in the 5-ASA group. 75% of patients treated with 5-ASA reported symptoms of a severe proctitis while only one patient in the placebo group had similar complaints. The application of Mesalazine as suppositories is not useful in preventing radiation induced proctitis during radiotherapy of prostate carcinoma.

  10. Severe side effects with the application of Mesalazine (5-aminosalicylic acid) during radiotherapy

    International Nuclear Information System (INIS)

    Freund, U.; Siems, H.; Wannenmacher, M.; Schoelmerich, J.; Kluge, F.; Schaefer, H.E.

    1987-01-01

    In a prospective randomized placebo controlled double blind study, the prophylactic effect of Mesalazine (5-aminosalicylic acid, 5-ASA) as suppositories (3x250 mg/day) on radiation induced proctitis during radiotherapy for prostatic carcinoma was studied. The study ended when 16 patients had been included (5-ASA: Eight, placebo: Eight) because of severe side effects in the 5-ASA group. 75% of patients treated with 5-ASA reported symptoms of a severe proctitis while only one patient in the placebo group had similar complaints. The application of Mesalazine as suppositories is not useful in preventing radiation induced proctitis during radiotherapy of prostate carcinoma. (orig.) [de

  11. Therapeutic effect of angiogenesis inhibitor combined with radiotherapy on liver metastasis model of colon cancer

    International Nuclear Information System (INIS)

    Jin Liugen; Zhou Shifu

    2005-01-01

    Objective: To observe the therapeutic effect of angiogenesis inhibitor combined with radiotherapy on liver metastasis model of colon cancer. Methods: Nude mice liver metastasis model of colon cancer was established with human colon cancer cells line (LS174T) inoculated into mice' spleen and followed by splenectomy. Angiogenesis inhibitor 2-ME and radiotherapy were administered after-wads. The growth inhibition effect on metastases and neovessel was examined. Results: The incidences of liver metastasis were 100% in this intrasplenic injection model. The mean weight and microvessel density 4 weeks after inoculation were 53.6 ± 4.7 mg, 8.4 ± 1.7 in treatment group as compared to 173.9 ± 11.6 mg, 41.2 ± 6.3 in control group respectively. Conclusion: 2-ME combined with radiotherapy has significant inhibition on the growth of liver metastases. Angiogenesis inhibition is one of the mechanisms of its efficiency. (authors)

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

    Science.gov (United States)

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

    2016-02-27

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

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

  14. High-dose preoperative chemoradiotherapy in esophageal cancer patients does not increase postoperative pulmonary complications: Correlation with dose-volume histogram parameters

    International Nuclear Information System (INIS)

    Hurmuzlu, Meysan; Ovrebo, Kjell; Wentzel-Larsen, Tore; Muren, Ludvig Paul; Viste, Asgaut; Smaaland, Rune

    2010-01-01

    Purpose: To investigate the association of high-dose preoperative chemoradiotherapy (CRT) and dose-volume histogram (DVH) parameters of lungs with incidence of postoperative pulmonary complications and to identify predictive clinical factors of pulmonary complications. Methods: Data of 65 patients were collected retrospectively. Thirty-five patients underwent transthoracic esophagectomy (TTE) alone and 30 received cisplatin and 5-fluorouracil, concomitant with radiotherapy, median dose 66 Gy, and followed by TTE. From the DVH for each lung alone and for both lungs together as one organ we generated total lung volume, mean radiotherapy dose, relative and absolute volumes receiving more than a threshold dose, and relative and absolute volumes receiving less than a threshold dose. Postoperative pulmonary complications were defined as pneumonia or respiratory failure. Results: Sixty percent of the patients in the TTE alone group had postoperative pulmonary complications versus 63% in the CRT + TTE group. Postoperative mortality was 8.6% and 16.7% in the respective patient groups (p = NS). None of the DVH parameters was associated with postoperative pulmonary complications. Squamous cell carcinoma was an adverse factor related to increased postoperative pulmonary complications. Conclusion: High-dose preoperative CRT was not associated with increased postoperative pulmonary complications in this cohort of esophageal cancer patients.

  15. Intensity-Modulated Radiotherapy of Head and Neck Cancer Aiming to Reduce Dysphagia: Early Dose-Effect Relationships for the Swallowing Structures

    International Nuclear Information System (INIS)

    Feng, Felix Y.; Kim, Hyungjin M.; Lyden, Teresa H.; Haxer, Marc J.; Feng, Mary; Worden, Frank P.; Chepeha, Douglas B.; Eisbruch, Avraham

    2007-01-01

    Purpose: To present initial results of a clinical trial of intensity-modulated radiotherapy (IMRT) aiming to spare the swallowing structures whose dysfunction after chemoradiation is a likely cause of dysphagia and aspiration, without compromising target doses. Methods and Materials: This was a prospective, longitudinal study of 36 patients with Stage III-IV oropharyngeal (31) or nasopharyngeal (5) cancer. Definitive chemo-IMRT spared salivary glands and swallowing structures: pharyngeal constrictors (PC), glottic and supraglottic larynx (GSL), and esophagus. Lateral but not medial retropharyngeal nodes were considered at risk. Dysphagia endpoints included objective swallowing dysfunction (videofluoroscopy), and both patient-reported and observer-rated scores. Correlations between doses and changes in these endpoints from pre-therapy to 3 months after therapy were assessed. Results: Significant correlations were observed between videofluoroscopy-based aspirations and the mean doses to the PC and GSL, as well as the partial volumes of these structures receiving 50-65 Gy; the highest correlations were associated with doses to the superior PC (p = 0.005). All patients with aspirations received mean PC doses >60 Gy or PC V 65 >50%, and GSL V 50 >50%. Reduced laryngeal elevation and epiglottic inversion were correlated with mean PC and GSL doses (p 70 >50%. Worsening patient-reported liquid swallowing was correlated with mean PC (p = 0.05) and esophageal (p 0.02) doses. Only mean PC doses were correlated with worsening patient-reported solid swallowing (p = 0.04) and observer-rated swallowing scores (p = 0.04). Conclusions: These dose-volume-effect relationships provide initial IMRT optimization goals and motivate further efforts to reduce swallowing structures doses to reduce dysphagia and aspiration

  16. Does partial expander deflation exacerbate the adverse effects of radiotherapy in two-stage breast reconstruction?

    Science.gov (United States)

    Celet Ozden, Burcu; Guven, Erdem; Aslay, Isik; Kemikler, Gonul; Olgac, Vakur; Soluk Tekkesin, Merva; Serarslan, Bengul; Tumerdem Ulug, Burcak; Bilgin Karabulut, Aylin; Arinci, Atilla; Emekli, Ufuk

    2012-02-20

    The optimum protocol for expander volume adjustment with respect to the timing and application of radiotherapy remains controversial. Eighteen New Zealand rabbits were divided into three groups. Metallic port integrated anatomic breast expanders of 250 cc were implanted on the back of each animal and controlled expansion was performed. Group I underwent radiotherapy with full expanders while in Group II, expanders were partially deflated immediately prior to radiotherapy. Control group did not receive radiotherapy.The changes in blood flow at different volume adjustments were investigated in Group II by laser Doppler flowmetry. Variations in the histopathologic properties of the irradiated tissues including the skin, capsule and the pocket floor, were compared in the biopsy specimens taken from different locations in each group. A significant increase in skin blood flow was detected in Group II with partial expander deflation. Overall, histopathologic exam revealed aggravated findings of chronic radiodermatitis (epidermal atrophy, dermal inflammation and fibrosis, neovascularisation and vascular changes as well as increased capsule thickness) especially around the lower expander pole, in Group II. Expander deflation immediately prior to radiotherapy, may augment the adverse effects, especially in the lower expander pole, possibly via enhanced radiosensitization due to a relative increase in the blood flow and tissue oxygenation.

  17. Does partial expander deflation exacerbate the adverse effects of radiotherapy in two-stage breast reconstruction?

    Directory of Open Access Journals (Sweden)

    Celet Ozden Burcu

    2012-02-01

    Full Text Available Abstract Background The optimum protocol for expander volume adjustment with respect to the timing and application of radiotherapy remains controversial. Methods Eighteen New Zealand rabbits were divided into three groups. Metallic port integrated anatomic breast expanders of 250 cc were implanted on the back of each animal and controlled expansion was performed. Group I underwent radiotherapy with full expanders while in Group II, expanders were partially deflated immediately prior to radiotherapy. Control group did not receive radiotherapy. The changes in blood flow at different volume adjustments were investigated in Group II by laser Doppler flowmetry. Variations in the histopathologic properties of the irradiated tissues including the skin, capsule and the pocket floor, were compared in the biopsy specimens taken from different locations in each group. Results A significant increase in skin blood flow was detected in Group II with partial expander deflation. Overall, histopathologic exam revealed aggravated findings of chronic radiodermatitis (epidermal atrophy, dermal inflammation and fibrosis, neovascularisation and vascular changes as well as increased capsule thickness especially around the lower expander pole, in Group II. Conclusions Expander deflation immediately prior to radiotherapy, may augment the adverse effects, especially in the lower expander pole, possibly via enhanced radiosensitization due to a relative increase in the blood flow and tissue oxygenation.

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

    International Nuclear Information System (INIS)

    Matuschek, Christiane; Ochtrop, Thomas A; Bölke, Edwin; Ganswindt, Ute; Fenk, Roland; Gripp, Stephan; Kröpil, Patric; Gerber, Peter Arne; Kammers, Kai; Hamilton, Jackson; Orth, Klaus; Budach, Wilfried

    2015-01-01

    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

  19. Late effects of external radiotherapy on the thyroid gland

    International Nuclear Information System (INIS)

    Monnier, A.

    1997-01-01

    The thyroid is the purest endocrine gland in the body and is likely to produce clinically significant abnormalities after external radiotherapy. Functional clinical modifications after direct irradiation exceeding 30 Gy are essentially related to hypothyroidism which may be clinically overt or subclinical with normal serum free thyroxine levels and high thyrotropin concentrations; the risk of hyperthyroidism, silent thyroiditis and Hashimoto's disease is also increased. secondary hypothyroidism related to irradiation of the hypothalamus and the pituitary gland may arise with doses over 40-50 Gy following treatment for brain and nasopharyngeal tumors - Morphological glandular modifications induced by radiotherapy are responsible for the appearance of benign adenomas, more rarely cystic degenerations and specially well differentiated papillary or follicular carcinomas among children and adults. After irradiation during childhood for benign or malignant tumors, thyroid cancers are more frequent, higher for younger children, and the relative excess risk is increased from 15.6-to 53-fold; tumors can belatedly occur, more than 35 years after initial therapy. Thereby, in order to limit excess morbidity, it is evident that long term supervision with careful clinical and biological evaluations is necessary for patients who previously received neck, upper mediastinum and pituitary radiation therapy. (author)

  20. Cytogenetic effects induced by radiotherapy of cancer patients

    International Nuclear Information System (INIS)

    Ekhtiar, A.; Al-Achkar, W.

    2008-03-01

    Ionizing radiation plays a key role in the treatment of many neoplasias. But it is well known that ionizing radiation induce wide specter of DNA damages, including SSBs, DSBs, base damage, and DNA-protein cross links. As a consequence, a second tumor may be developed after the primary tumor therapy. Attempts have been made to evaluate the genotoxicity of ionizing radiation in patients undergoing radiotherapy. In the present work, the cytogenetic damage present in peripheral blood lymphocytes of patients (29 donors) treated with fractionated partial-body radiation therapy for Head-and-neck cancer patient was followed before, during and at the end of treatment by means of the cytokinesis-block micronucleus assay. These patients had no previous chemotherapy or radiotherapy. Our results indicate that the level of spontaneous cytogenetic damage in cancer patients and smokers control (3 donors) were higher than in healthy non smoking controls (3 donor). During and after treatment, increased of micronucleus cells frequencies were observed with increasing treatment doses.(author)

  1. An assessment of effective dose to staff in external beam radiotherapy

    International Nuclear Information System (INIS)

    Rawlings, D.J.; Nicholson, L.

    1997-01-01

    Radiation safety in external beam radiotherapy is governed by national legislation. Annual doses recorded by radiographers and others associated with external beam radiotherapy are typically much lower than the relevant dose limit. However, it is possible that larger doses might be received as a result of an accidental irradiation. In the event of a significant exposure resulting in a dose at or near a relevant dose limit, an accurate conversion has to be made from the dose meter reading to the limiting quantity. A method was devised to demonstrate ratios of effective dose to personal dose equivalent which might be anticipated in the even of an individual other than the patient being irradiated within a radiotherapy treatment room consisting of a linear accelerator. The variation of ratios obtained under different conditions is discussed. (author)

  2. Late effects of adjuvant chemotherapy and postoperative radiotherapy on quality of life among breast cancer patients

    International Nuclear Information System (INIS)

    Berglund, G.; Bolund, C.; Fornander, T.; Rutqvist, L.E.; Sjoeden, P.-O.

    1991-01-01

    Late effects of adjuvant treatment on perceived health and quality of life were assessed through a questionnaire mailed to 448 premenopausal and postmenopausal breast cancer patients, free from recurrence 2-10 years after primary therapy. The patients had been randomised to postoperative radiotherapy or adjuvant chemotherapy as adjuncts to primary surgery. The differences between the two treatments were generally small. However, the radiotherapy patients had significantly greater problems with decreased stamina, symptoms related to the operation scar and anxiety. The chemotherapy patients had significantly more problems with smell aversion. Activity level inside and outside the home, anxiousness and depressive symptoms were similar in both groups. The chemotherapy patients scored their overall quality of life higher than the radiotherapy patients. (author)

  3. Late effects of adjuvant chemotherapy and postoperative radiotherapy on quality of life among breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, G.; Bolund, C.; Fornander, T.; Rutqvist, L.E. (Karolinska Sjukhuset, Stockholm (Sweden)); Sjoeden, P.-O. (Uppsala Univ. (Sweden))

    1991-09-01

    Late effects of adjuvant treatment on perceived health and quality of life were assessed through a questionnaire mailed to 448 premenopausal and postmenopausal breast cancer patients, free from recurrence 2-10 years after primary therapy. The patients had been randomised to postoperative radiotherapy or adjuvant chemotherapy as adjuncts to primary surgery. The differences between the two treatments were generally small. However, the radiotherapy patients had significantly greater problems with decreased stamina, symptoms related to the operation scar and anxiety. The chemotherapy patients had significantly more problems with smell aversion. Activity level inside and outside the home, anxiousness and depressive symptoms were similar in both groups. The chemotherapy patients scored their overall quality of life higher than the radiotherapy patients. (author).

  4. Investigations about late effects of exclusive radiotherapy of tumors of the epipharynx

    Energy Technology Data Exchange (ETDEWEB)

    Richter, E

    1982-09-01

    The late effects of ionizing radiation after radiotherapeutic healing of malignant tumors are of great interest. A report is given on sixteen patients with a malignant tumor of the epipharynx, who had been exclusively treated by radiotherapy and are regarded as cured. Only four of these patients had no complaints when examined, the others presented symptoms which were partly due to radiotherapy. The most important symptoms were rhinitis sicca and pharyngitis sicca induced by radiation. The complaints now indicated by the patients and the results of thorough clinical examinations are discussed and compared to communications of literature.

  5. The study on the immunological effect of Sizofilan combined with radiotherapy in patients with uterine cervical cancer

    International Nuclear Information System (INIS)

    Sekiguchi, Isao; Suzuki, Mitsuaki; Izumi, Akio; Aida, Ichiro; Tamada, Taro

    1990-01-01

    To investigate the immunological effect of Sizofilan (SPG) combined with radiotherapy, we evaluated the immunological parameters in 22 patients with uterine cervical cancer. Twelve patients were treated with SPG combined with radiotherapy (SPG group), and the other ten patients with radiotherapy only (control group). During radiotherapy, the numbers of lymphocyte and CD2 positive cell decreased in the SPG and control groups. After radiotherapy, however, its numbers in the SPG group became significantly higher than in the control group (p<0.05). The number of CD3 positive cell also presented a tendency to increase after radiotherapy in the SPG group. As for CD20 positive cell, its numbers were kept unchanged after radiotherapy in both groups, and no significant difference was observed between them. NK cell activity decreased during radiotherapy in both groups. After radiotherapy, its activity in the SPG group recovered to its pre-value and became significantly higher than that in the control group (p<0.05). SPG did not have any prominent effect on CD4/CD8 ratio. The adverse effect of SPG to liver or kidney function was not observed in our patients. The SCC level in the SPG group decreased rapidly by radiotherapy as well as that in the control group, and no significant difference was observed in SCC levels between them. So it was suggested that SPG did not suppress the cytocidal effect of radiation to cancer cells. Based on these findings, it was concluded that SPG prompted the recovery of not only lymphocyte, especially T cell, but also NK cell activity. These immunological findings presented a usefulness of clinical application of SPG to radiotherapy in patients with uterine cervical cancer. (author)

  6. Radioactive EGFR Antibody Cetuximab in Multimodal Cancer Treatment: Stability and Synergistic Effects With Radiotherapy

    International Nuclear Information System (INIS)

    Rades, Dirk; Wolff, Christian; Nadrowitz, Roger; Breunig, Christian; Schild, Steven E.; Baehre, Manfred; Meller, Birgit

    2009-01-01

    Purpose: Systemic therapies when added to whole brain radiotherapy have failed to improve the survival of patients with multiple brain metastases. The epidermal growth factor receptor antibody cetuximab is an attractive option, if it is able to cross the blood-brain barrier. This might be proven with molecular imaging if the radiolabeled antibody is stable long enough to be effective. This study investigated the stability of radiolabeled cetuximab (Erbitux) ( 131 I-Erbi) and potential synergistic effects with radiotherapy in vitro. Methods and Materials: Two cell lines were investigated, A431 with numerous epidermal growth factor receptors, and JIMT without epidermal growth factor receptors. We labeled 0.4 mg cetuximab with 50 MBq of [ 131 I] iodide. Stability was determined for 72 h. The cell cultures were incubated with 131 I-Erbi or cold cetuximab for 72 h. Uptake and cell proliferation were measured every 24 h after no radiotherapy or irradiation with 2, 4, or 10 Gy. Results: The radiolabeling yield of 131 I-Erbi was always >80%. The radiochemical purity was still 93.6% after 72 h. A431 cells showed a 131 I-Erbi uptake about 100-fold greater than the JIMT controls. After 48 h, the A431 cultures showed significantly decreased proliferation. At 72 h after irradiation, 131 I-Erbi resulted in more pronounced inhibition of cell proliferation than the cold antibody in all radiation dose groups. Conclusion: 131 I-Erbi was stable for ≤72 h. Radiotherapy led to increased tumor cell uptake of 131 I-Erbi. Radiotherapy and 131 I-Erbi synergistically inhibited tumor cell proliferation. These results provide the prerequisite data for a planned in vivo study of whole brain radiotherapy plus cetuximab for brain metastases.

  7. A comparison of the palliative effects of strontium-89 and external beam radiotherapy in metastatic prostate cancer

    International Nuclear Information System (INIS)

    Quilty, P.M.; Kirk, D.; Bolger, J.J.; Dearnaley, D.P.; Mason, M.D.; Lewington, V.J.; Reed, N.S.E.; Russell, J.M.; Yardley, J.

    1994-01-01

    From 1988 to 1991, 284 patients with prostatic cancer and painful bone metastases were treated with either radiotherapy or strontium-89 (200 MBq). Patients were first stratified according to suitability for local or hemibody radiotherapy, then randomly allocated that form of treatment or strontium-89 (i.v. injection). After 4,8 and 12 weeks pain sites were mapped, toxicity monitored, and all additional palliative treatments recorded. There was no significant difference in median survival (after >80% had died); 33 weeks following strontium 8 9 and 28 weeks following radiotherapy (p=0.1). All treatments provided effective pain relief; improvement was sustained to 3 months in 63.6% after hemibody radiotherapy compared with 66.1% after strontium-89, and in 61% after local radiotherapy compared with 65.9% in the comparable strontium 8 9 group. Fewer patients reported new pain sites after strontium-89 than after local or hemibody radiotherapy (p < 0.05). Radiotherapy to a new site was required by 12 patients in the local radiotherapy group compared with 2 after strontium-89 (p < 0.01), although there was no significant difference between hemibody radiotherapy (6 patients) and strontium-89 (9 patients) in this respect. Platelets and leukocytes fell by an average 30-40% after strontium-89 but sequelae were uncommon, and other symptoms rare

  8. Methodological issues in radiation dose-volume outcome analyses: Summary of a joint AAPM/NIH workshop

    International Nuclear Information System (INIS)

    Deasy, Joseph O.; Niemierko, Andrzej; Herbert, Donald; Yan, Di; Jackson, Andrew; Ten Haken, Randall K.; Langer, Mark; Sapareto, Steve

    2002-01-01

    This report represents a summary of presentations at a joint workshop of the National Institutes of Health and the American Association of Physicists in Medicine (AAPM). Current methodological issues in dose-volume modeling are addressed here from several different perspectives. Areas of emphasis include (a) basic modeling issues including the equivalent uniform dose framework and the bootstrap method, (b) issues in the valid use of statistics, including the need for meta-analysis, (c) issues in dealing with organ deformation and its effects on treatment response, (d) evidence for volume effects for rectal complications, (e) the use of volume effect data in liver and lung as a basis for dose escalation studies, and (f) implications of uncertainties in volume effect knowledge on optimized treatment planning. Taken together, these approaches to studying volume effects describe many implications for the development and use of this information in radiation oncology practice. Areas of significant interest for further research include the meta-analysis of clinical data; interinstitutional pooled data analyses of volume effects; analyses of the uncertainties in outcome prediction models, minimal parameter number outcome models for ranking treatment plans (e.g., equivalent uniform dose); incorporation of the effect of motion in the outcome prediction; dose-escalation/isorisk protocols based on outcome models; the use of functional imaging to study radio-response; and the need for further small animal tumor control probability/normal tissue complication probability studies

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  10. The analysis of correlation between changes of myocardial enzymes level in serum before and after radiation and dose-volume histogram parameters of the heart

    International Nuclear Information System (INIS)

    Ding Xiuping; Li Hongjun; Li Baosheng; Wang Dongqing

    2012-01-01

    Objective: To analyze the correlation between the changes of myocardial enzyme level in serum before and after radiotherapy and dose - volume histogram (DVH) parameters of the heart. Methods: A total of 102 patients with 68 cases of lung cancer and 34 cases of esophageal cancer were recruited. All patients received three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT), with the radiation beams passing through the heart. Aspartate aminotransferase (AST), creatine kinase (CK), creatine kinase isozyme (CK-MB), lactate dehydrogenase (LDH), α-hydroxybutyrate dehydrogenase (α-HBDH) were determined in the serum before and after radiotherapy. All the enzyme levels before and after radiotherapy were compared through paired t-test. Independent sample t-test was conducted between sub-groups. And the dose-volume histogram (DVH) parameters of the heart were calculated (the volume percentage of heart receiving dose equal to or exceeding x Gy (V x ). The correlation between myocardial enzyme level and DVH parameters was analyzed through Pearson method. Results: Serum AST, CK-MB, LDH, α-HBDH levels increased significantly after radiotherapy (19.42: 27.89, 14.72:19.57, 178.80 : 217.57, 140.32 : 176.25, t =-3.39 - -6.92, all P=0.000). In Group IMRT, significant correlations between the increase of myocardial enzyme concentration and DVH parameters of the heart are found, AST with V 20 , V 25 , V 30 of heart ( r=0.302 - 0.431, P =0.039 - 0.003), CK with V 30 of heart (r=0.345, P=0.013), and CK-MB, LDH, α-HBDH with V 25 , V 30 (r=0.465 -0.376, P=0.001-0.005). In Group CRT, there are significant correlations between changes of CK-MB, LDH level and V 30 of heart (r =0.330, 0.274, P=0.014, 0.033), α-HBDH and V 25 , V 30 , and V 35 of heart (r=0.270-0.331, P=0.046-0.014). When the irradiation dose was more than 50 Gy, significant correlations were found between the concentration changes of AST, LDH, α-HBDH and V 25 , V 30 of heart (r=0

  11. Side effects of radiotherapy in regime of dynamic dose multifractioning for local larynx cancer forms

    International Nuclear Information System (INIS)

    Slobina, E.L.

    2000-01-01

    A regime for dynamic multifractioning of radiotherapy dose used for treating larynx cancer was developed. The method favored reducing the side effects frequency as compared with the conventional fractioning in larynx mucosa from 70% to 46%, in neck skin being irradiated - from 60% to 48%

  12. Multinational study exploring patients' perceptions of side-effects induced by chemo-radiotherapy

    DEFF Research Database (Denmark)

    Ruhlmann, Christina H; Iversen, Trine Zeeberg; Okera, Meena

    2015-01-01

    PURPOSE: We aimed to prospectively assess the incidence, severity and patients' perceptions of side-effects induced by radiotherapy and concomitant weekly cisplatin. PATIENTS AND METHODS: This multinational survey included patients with a diagnosis of gynaecological or head and neck cancer schedu...

  13. Genetic Predictors of Adverse Radiotherapy Effects: the Gene-PARE project

    DEFF Research Database (Denmark)

    Ho, Alice Y.; Atencio, David P.; Peters, Sheila

    2006-01-01

    PURPOSE: The development of adverse effects resulting from the radiotherapy of cancer limits the use of this treatment modality. The validation of a test capable of predicting which patients would be most likely to develop adverse responses to radiation treatment, based on the possession of speci...

  14. Dose-effect relationships for individual pelvic floor muscles and anorectal complaints after prostate radiotherapy.

    NARCIS (Netherlands)

    Smeenk, R.J.; Hoffmann, A.L.; Hopman, W.P.M.; Lin, E.N.J.T. van; Kaanders, J.H.A.M.

    2012-01-01

    PURPOSE: To delineate the individual pelvic floor muscles considered to be involved in anorectal toxicity and to investigate dose-effect relationships for fecal incontinence-related complaints after prostate radiotherapy (RT). METHODS AND MATERIALS: In 48 patients treated for localized prostate

  15. Dose-volume based ranking of incident beam direction and its utility in facilitating IMRT beam placement

    International Nuclear Information System (INIS)

    Schreibmann, Eduard; Xing Lei

    2005-01-01

    Purpose: Beam orientation optimization in intensity-modulated radiation therapy (IMRT) is computationally intensive, and various single beam ranking techniques have been proposed to reduce the search space. Up to this point, none of the existing ranking techniques considers the clinically important dose-volume effects of the involved structures, which may lead to clinically irrelevant angular ranking. The purpose of this work is to develop a clinically sensible angular ranking model with incorporation of dose-volume effects and to show its utility for IMRT beam placement. Methods and Materials: The general consideration in constructing this angular ranking function is that a beamlet/beam is preferable if it can deliver a higher dose to the target without exceeding the tolerance of the sensitive structures located on the path of the beamlet/beam. In the previously proposed dose-based approach, the beamlets are treated independently and, to compute the maximally deliverable dose to the target volume, the intensity of each beamlet is pushed to its maximum intensity without considering the values of other beamlets. When volumetric structures are involved, the complication arises from the fact that there are numerous dose distributions corresponding to the same dose-volume tolerance. In this situation, the beamlets are not independent and an optimization algorithm is required to find the intensity profile that delivers the maximum target dose while satisfying the volumetric constraints. In this study, the behavior of a volumetric organ was modeled by using the equivalent uniform dose (EUD). A constrained sequential quadratic programming algorithm (CFSQP) was used to find the beam profile that delivers the maximum dose to the target volume without violating the EUD constraint or constraints. To assess the utility of the proposed technique, we planned a head-and-neck and abdominal case with and without the guidance of the angular ranking information. The qualities of the

  16. 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

  17. Influence of the contrast agents on dose-volume histograms in radiotherapy treatment planning based on CT-scan

    Directory of Open Access Journals (Sweden)

    Sahel Heydarheydari

    2018-02-01

    Conclusion: The results showed statistical insignificant difference between with and without CA CTs treatment plan in pelvic field for targets and OARs. These results may serve as a reference to justify the use of CECT data sets for 3D-CRT planning of pelvic region cancers using DosiSoft ISOgray system.

  18. Agreement of quadratic and CRE models in predicting the late effects of continuous low dose-rate radiotherapy; and reply

    International Nuclear Information System (INIS)

    O'Donoghue, J.A.

    1986-01-01

    These letters discuss the problems associated with the fact that the normal tissue isoeffect formulae based on the Ellis equation (1969) do not correctly account for the late-occurring effects of fractionated radiotherapy, and with the extension of the linear quadratic model to include continuous low dose-rate radiotherapy with constant or decaying sources by R.G. Dale (1985). J.A. O'Donoghue points out that the 'late effects' and CRE curves correspond closely, whilst the 'acute effects; and CRE curves are in obvious disagreement. For continuous low-dose-rate radiotherapy, the CRE and late effects quadratic model are in agreement. Useful bibliography. (U.K.)

  19. The effect of endostatin gene in combination with radiotherapy on rats with implanted tumor

    International Nuclear Information System (INIS)

    Li Yong; Jin Ning; Yang Haishan; Piao Chunji; Lv Zhe

    2005-01-01

    Objective: To study the combination therapy effect of the radiotherapy with endostatin gene therapy on the rats with implanted tumor. Methods: Immediate Walker-256 cancerous ascetic injection method was used to make a rat tumor-bearing model, then the tumor was treated with saline, endostatin gene, irradiation or endostatin gene plus irradiation. The tumor growth rate and weight were observed, Western blot and RT-PCR were adopted to check the expressions of endostatin mRNA and protein. Results: The expressions of endostatin mRNA and protein were significant in the gene therapy group and the gene plus radiotherapy group, but there was a significant difference between these two groups. As compared with the control group, the tumor growth rate and weight decreased significantly in all the therapy groups (P 0.05). Conclusion: After the pCMV-Endostatin was induced, the expressions of endostatin mRNA and protein was significant in Walker-256 tumor and the tumor growth was inhibited. However, the effect of the endostatin gene plus radiotherapy was obviously better than that of the endostatin gene therapy group or the radiotherapy group for inhibiting tumor growth. (authors)

  20. 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.

  1. Limits of dose escalation in lung cancer: a dose-volume histogram analysis comparing coplanar and non-coplanar techniques

    Energy Technology Data Exchange (ETDEWEB)

    Derycke, S; Van Duyse, B; Schelfhout, J; De Neve, W

    1995-12-01

    To evaluate the feasibility of dose escalation in radiotherapy of inoperable lung cancer, a dose-volume histogram analysis was performed comparing standard coplanar (2D) with non-coplanar (3D) beam arrangements on a non-selected group of 20 patients planned by Sherouse`s GRATISTM 3D-planning system. Serial CT-scanning was performed and 2 Target Volumes (Tvs) were defined. Gross Tumor Volume (GTV) defined a high-dose Target Volume (TV-1). GTV plus location of node stations with > 10% probability of invasion (Minet et al.) defined an intermediate-dose Target Volume (TV-2). However, nodal regions which are incompatible with cure were excluded from TV-2. These are ATS-regions 1, 8, 9 and 14 all left and right as well as heterolateral regions. For 3D-planning, Beam`s Eye View selected (by an experienced planner) beam arrangements were optimised using Superdot, a method of target dose-gradient annihilation developed by Sherouse. A second 3D-planning was performed using 4 beam incidences with maximal angular separation. The linac`s isocenter for the optimal arrangement was located at the geometrical center of gravity of a tetraheder, the tetraheder`s comers being the consecutive positions of the virtual source. This ideal beam arrangement was approximated as close as possible, taking into account technical limitations (patient-couch-gantry collisions). Criteria for tolerance were met if no points inside the spinal cord exceeded 50 Gy and if at least 50% of the lung volume received less than 20Gy. If dose regions below 50 Gy were judged acceptable at TV-2, 2D- as well as 3D-plans allow safe escalation to 80 Gy at TV-1. When TV-2 needed to be encompassed by isodose surfaces exceeding 50Gy, 3D-plans were necessary to limit dose at the spinal cord below tolerance. For large TVs dose is limited by lung tolerance for 3D-plans. An analysis (including NTCP-TCP as cost functions) of rival 3D-plans is being performed.

  2. Dose-Volume Relationships for Acute Bowel Toxicity in Patients Treated With Pelvic Nodal Irradiation for Prostate Cancer

    International Nuclear Information System (INIS)

    Fiorino, Claudio; Alongi, Filippo; Perna, Lucia; Broggi, Sara; Cattaneo, Giovanni Mauro; Cozzarini, Cesare; Di Muzio, Nadia; Fazio, Ferruccio; Calandrino, Riccardo

    2009-01-01

    Purpose: To find correlation between dose-volume histograms (DVHs) of the intestinal cavity (IC) and moderate-severe acute bowel toxicity in men with prostate cancer treated with pelvic nodal irradiation. Methods and Materials: The study group consisted of 191 patients with localized prostate cancer who underwent whole-pelvis radiotherapy with radical or adjuvant/salvage intent during January 2004 to November 2007. Complete planning/clinical data were available in 175 of these men, 91 of whom were treated with a conventional four-field technique (50.4 Gy, 1.8 Gy/fraction) and 84 of whom were treated with IMRT using conventional Linac (n = 26, 50.4 Gy, 1.8 Gy/fraction) or Helical TomoTherapy (n = 58, 50-54 Gy, 1.8-2 Gy/fraction). The IC outside the planning target volume (PTV) was contoured and the DVH for the first 6 weeks of treatment was recovered in all patients. The correlation between a number of clinical and DVH (V10-V55) variables and toxicity was investigated in univariate and multivariate analyses. The correlation between DVHs for the IC outside the PTV and DVHs for the whole IC was also assessed. Results: Twenty-two patients experienced toxicity (3/22 in the IMRT/tomotherapy group). Univariate analyses showed a significant correlation between V20-V50 and toxicity (p = 0.0002-0.001), with a higher predictive value observed for V40-V50. Previous prostatectomy (p = 0.066) and abdominal/pelvic surgery (p = 0.12) also correlated with toxicity. Multivariate analysis that included V45, abdominal/pelvic surgery, and prostatectomy showed that the most predictive parameters were V45 (p = 0.002) and abdominal/pelvic surgery (p = 0.05, HR = 2.4) Conclusions: Our avoidance IMRT approach drastically reduces the incidence of acute bowel toxicity. V40-V50 of IC and, secondarily, previous abdominal/pelvic surgery were the main predictors of acute bowel toxicity.

  3. Protective effect of amifostine on dental health after radiotherapy of the head and neck

    International Nuclear Information System (INIS)

    Rudat, Volker; Meyer, Jens; Momm, Felix; Bendel, Martin; Henke, Michael; Strnad, Vratislav; Groetz, Knut; Schulte, Andreas

    2000-01-01

    Purpose: The cytoprotective agent amifostine has been shown to reduce the radiation-induced acute and chronic xerostomia in head and neck cancer patients. The purpose of this study was to evaluate whether or not amifostine also reduces the incidence of dental caries associated with the radiation-induced xerostomia. Methods and Materials: The dental status before and 1 year after radiotherapy was retrospectively compared in 35 unselected patients treated as part of the prospective randomized and multicenter open-label Phase III study (WR-38) at the University Hospitals of Heidelberg, Freiburg, and Erlangen. The WR-38 study compared radiotherapy in head and neck cancer with and without concomitant administration of amifostine. Results: Patient and treatment characteristics (particularly the radiation dose and percentage of parotids included in the treatment volume) were equally distributed between the patients who received (n = 17) or did not receive (n = 18) amifostine. Fifteen patients of the amifostine group showed no deterioration of the dental status 1 year after radiotherapy as compared to 7 patients who did not receive the cytoprotector (p = 0.015, two-tailed Fisher exact test). Conclusion: Our data suggest a protective effect of amifostine on the dental health after radiotherapy of the head and neck. The dental status should be used as a primary endpoint in future studies on amifostine.

  4. The effect of radiotherapy on NKT cells in patients with advanced head and neck cancer.

    Science.gov (United States)

    Kobayashi, Kouichi; Tanaka, Yuriko; Horiguchi, Shigetoshi; Yamamoto, Shouji; Toshinori, Nakayama; Sugimoto, Akira; Okamoto, Yoshitaka

    2010-10-01

    Cancer immunotherapy with NKT cells is a potential new treatment strategy for advanced head and neck cancer. NKT cell therapy is promising due to its unique anti-tumor activity and higher degree of safety compared to current therapies. Radiotherapy is indispensable as a standard treatment for advanced head and neck cancer. To elucidate the possibility of using NKT cells as an adjuvant immunotherapy with radiotherapy, we examined the effect of radiotherapy on NKT cells in patients with head and neck cancer. The number, IFN-gamma production and proliferation capacity of NKT cells were analyzed before and after 50 Gy radiation therapy in 12 patients with stage IV head and neck squamous cell carcinoma. The cytotoxic activity of NKT cells was examined in vitro. The number of NKT cells in the blood varied widely between patients. After radiation therapy, the population of CD3 T cells decreased significantly, while the NKT cell population remained stable. The number of NKT cells was the same after radiation therapy as before. IFN-gamma production from NKT cells collected just after radiotherapy was impaired after stimulation with exogenous ligand, but the proliferative responses of these NKT cells was enhanced in comparison to those collected before radiation therapy. Furthermore, the proliferated NKT cells displayed a significant level of anti-tumor activity. NKT cells are relatively resistant to radiation and might therefore be suitable for adjuvant immunotherapy to eradicate remnant cancer cells in patients who have undergone radiation therapy.

  5. Effect of ionizing radiation on the taste function of patients submitted to head and neck radiotherapy

    International Nuclear Information System (INIS)

    Silva, Amaro Ilidio Vespasiano; Galante, Celio

    2011-01-01

    Objective: to evaluate the effects of ionizing radiation on the taste function in patients submitted to radiotherapy in the head and neck region. Materials and methods: twenty patients diagnosed with head and neck tumors and undergoing treatment in the Division of Radiotherapy at Santa Casa de Misericordia de Belo Horizonte, MG, Brazil, were selected. For their taste function testing, four solutions were manipulated with salt (NaCl), sugar (sucrose), citric acid (for acidity), and urea (for bitterness), at three different (low, medium and high) concentrations. Weekly tests were performed during the first three weeks of radiotherapy, with random administration of the solutions (three drops each) respecting the order of their concentration levels (low, medium and high). After the application of each solution, the patient reported which flavor he/she tasted. Results: a statistically significant difference was observed in the loss of taste function as the results in the 1st and 4th weeks of treatment were compared, with salty solution at the three concentration levels, with the sweet solution at low and medium concentrations, and with the sour and bitter solutions, only at low concentration. Conclusion: ionizing radiation alters the taste function of patients submitted to head and neck radiotherapy. (author)

  6. Cosmetic outcome and curative effect of radiotherapy for early breast cancer after conservative surgery

    International Nuclear Information System (INIS)

    Ma Changuo; Ma Yuanyuan; Zhao Shuhong; Wang Hong

    2007-01-01

    Objective: To study the cosmetic outcome and curative effect of 6 MV X-ray tangential field radiotherapy for early stage breast cancer after conservative surgery. Methods: The eligible criteria were single tumor ≤3 cm in diameter, surgical margin negative and lymph node negative. The exclusive criteria were inflammatory carcinoma or male breast cancer. After conservative surgery, 42 patients with stage 0, I or II breast cancer were treated with conventional radiotherapy with a total dose of 50 Gy to the whole breast and 10 Gy boost to the tumor bed. The efficacy and the cosmetic outcome of radiotherapy were evaluated every 3 months for the first 2 years and every 6 months after that and every 12 months after 5 years. Results: The follow up time was 19-90 months (median 56 months). Two patients died of metastasis after 16 months and 36 months, which was diagnosed by CT scan. Excellent or good cosmetic outcome was > 93% at 36 months. The local control rate was 100%. The 1- and 3-year survival rates was 100% and 98%, respectively. Conclusions: Tangential field radiotherapy for early breast cancer after conservative surgery has a satisfied result in both tumor control and cosmetic outcome, which can definitely improve the life quality of the patients. (authors)

  7. Effect of ionizing radiation on the taste function of patients submitted to head and neck radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Amaro Ilidio Vespasiano [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Galante, Celio [Santa Casa de Misericordia de Belo Horizonte, MG (Brazil). Div. de Radioterapia; Manzi, Flavio Ricardo, E-mail: manzi@pucminas.b [Pontificia Universidade Catolica de Minas Gerais (PUC-MG), Belo Horizonte, MG (Brazil)

    2011-09-15

    Objective: to evaluate the effects of ionizing radiation on the taste function in patients submitted to radiotherapy in the head and neck region. Materials and methods: twenty patients diagnosed with head and neck tumors and undergoing treatment in the Division of Radiotherapy at Santa Casa de Misericordia de Belo Horizonte, MG, Brazil, were selected. For their taste function testing, four solutions were manipulated with salt (NaCl), sugar (sucrose), citric acid (for acidity), and urea (for bitterness), at three different (low, medium and high) concentrations. Weekly tests were performed during the first three weeks of radiotherapy, with random administration of the solutions (three drops each) respecting the order of their concentration levels (low, medium and high). After the application of each solution, the patient reported which flavor he/she tasted. Results: a statistically significant difference was observed in the loss of taste function as the results in the 1st and 4th weeks of treatment were compared, with salty solution at the three concentration levels, with the sweet solution at low and medium concentrations, and with the sour and bitter solutions, only at low concentration. Conclusion: ionizing radiation alters the taste function of patients submitted to head and neck radiotherapy. (author)

  8. Hypothyroidism after radiotherapy to the neck

    International Nuclear Information System (INIS)

    Yoden, Eisaku; Soejima, Toshinori; Maruta, Tsutomu; Demizu, Yusuke; Nishimura, Hideki; Ejima, Yasuo; Sasaki, Ryohei; Yamada, Kazunari; Sugimura, Kazuro

    2004-01-01

    The purpose of this study was to investigate the incidence and possible predictors of hypothyroidism after radiotherapy to the neck, focusing on radiation dose-volume factors. Thyroid function was measured in 169 patients treated with radiation ports including the thyroid, between 1989 and 2000. Hypothyroidism was determined with an endpoint of elevated serum thyroid stimulating hormone (TSH) levels >10.0 μU/ml. In 60 patients, radiation dose-volume factors were calculated; e.g., total volume of the thyroid, mean radiation dose to the thyroid, and %-volume of the thyroid which received radiation doses of no less than 10-70 Gy (V 10 -V 70 ). The evaluated risk factors for hypothyroidism included these dose-volume factors, sex, age, primary disease, combined chemotherapy, and follow-up period. Hypothyroidism was detected in 33 (19.5%) of the 169 patients. None of them had clinical symptoms of hypothyroidism. V 10 , V 20 , and V 30 seemed to be possible predictors of hypothyroidism and had a significant impact on the peak level of serum TSH. Radiation dose-volume factors of the thyroid seemed to correlate with the incidence of hypothyroidism, and V 10 , V 20 , and V 30 had a significant impact on the peak level of serum TSH. (author)

  9. Radiotherapy and 'new' drugs-new side effects?

    International Nuclear Information System (INIS)

    Niyazi, Maximilian; Maihoefer, Cornelius; Krause, Mechthild; Rödel, Claus; Budach, Wilfried; Belka, Claus

    2011-01-01

    Targeted drugs have augmented the cancer treatment armamentarium. Based on the molecular specificity, it was initially believed that these drugs had significantly less side effects. However, currently it is accepted that all of these agents have their specific side effects. Based on the given multimodal approach, special emphasis has to be placed on putative interactions of conventional cytostatic drugs, targeted agents and other modalities. The interaction of targeted drugs with radiation harbours special risks, since the awareness for interactions and even synergistic toxicities is lacking. At present, only limited is data available regarding combinations of targeted drugs and radiotherapy. This review gives an overview on the current knowledge on such combined treatments. Using the following MESH headings and combinations of these terms pubmed database was searched: Radiotherapy AND cetuximab/trastuzumab/panitumumab/nimotuzumab, bevacizumab, sunitinib/sorafenib/lapatinib/gefitinib/erlotinib/sirolimus, thalidomide/lenalidomide as well as erythropoietin. For citation crosscheck the ISI web of science database was used employing the same search terms. Several classes of targeted substances may be distinguished: Small molecules including kinase inhibitors and specific inhibitors, antibodies, and anti-angiogenic agents. Combination of these agents with radiotherapy may lead to specific toxicities or negatively influence the efficacy of RT. Though there is only little information on the interaction of molecular targeted radiation and radiotherapy in clinical settings, several critical incidents are reported. The addition of molecular targeted drugs to conventional radiotherapy outside of approved regimens or clinical trials warrants a careful consideration especially when used in conjunction in hypo-fractionated regimens. Clinical trials are urgently needed in order to address the open question in regard to efficacy, early and late toxicity

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  11. Inverse optimization of objective function weights for treatment planning using clinical dose-volume histograms

    Science.gov (United States)

    Babier, Aaron; Boutilier, Justin J.; Sharpe, Michael B.; McNiven, Andrea L.; Chan, Timothy C. Y.

    2018-05-01

    We developed and evaluated a novel inverse optimization (IO) model to estimate objective function weights from clinical dose-volume histograms (DVHs). These weights were used to solve a treatment planning problem to generate ‘inverse plans’ that had similar DVHs to the original clinical DVHs. Our methodology was applied to 217 clinical head and neck cancer treatment plans that were previously delivered at Princess Margaret Cancer Centre in Canada. Inverse plan DVHs were compared to the clinical DVHs using objective function values, dose-volume differences, and frequency of clinical planning criteria satisfaction. Median differences between the clinical and inverse DVHs were within 1.1 Gy. For most structures, the difference in clinical planning criteria satisfaction between the clinical and inverse plans was at most 1.4%. For structures where the two plans differed by more than 1.4% in planning criteria satisfaction, the difference in average criterion violation was less than 0.5 Gy. Overall, the inverse plans were very similar to the clinical plans. Compared with a previous inverse optimization method from the literature, our new inverse plans typically satisfied the same or more clinical criteria, and had consistently lower fluence heterogeneity. Overall, this paper demonstrates that DVHs, which are essentially summary statistics, provide sufficient information to estimate objective function weights that result in high quality treatment plans. However, as with any summary statistic that compresses three-dimensional dose information, care must be taken to avoid generating plans with undesirable features such as hotspots; our computational results suggest that such undesirable spatial features were uncommon. Our IO-based approach can be integrated into the current clinical planning paradigm to better initialize the planning process and improve planning efficiency. It could also be embedded in a knowledge-based planning or adaptive radiation therapy framework to

  12. The effect on esophagus after different radiotherapy techniques for early stage Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Jørgensen, Anni; Maraldo, M.; Brodin, Nils Patrik

    2013-01-01

    The cure rate of early stage Hodgkin's lymphoma (HL) is excellent; investigating the late effects of treatment is thus important. Esophageal toxicity is a known side effect in patients receiving radiotherapy (RT) to the mediastinum, although little is known of this in HL survivors. This study inv...... investigates the dose to the esophagus in the treatment of early stage HL using different RT techniques. Estimated risks of early esophagitis, esophageal stricture and cancer are compared between treatments....

  13. The effect of UV-light on DNA metabolism of lymphocytes during radiotherapy

    International Nuclear Information System (INIS)

    Klein, W.; Altmann, H.; Klein, H.; Alth, G.; Koren, H.

    1980-02-01

    The effects of gamma plus electron therapy and only gammatherapy, respectively, were investigated in lymphocytes of the peripheral blood of 10 patients with malignancies. The efficiency of DNA repair was tested by an irradiation of the cells with UV light beside radiotherapy. Using only gamma rays for therapy, the effects by UV light were not so pronounced than for using gamma plus electron therapy. (author)

  14. Feasibility of using intensity-modulated radiotherapy to improve lung sparing in treatment planning for distal esophageal cancer

    International Nuclear Information System (INIS)

    Chandra, Anurag; Guerrero, Thomas M.; Liu, H. Helen; Tucker, Susan L.; Liao Zhongxing; Wang Xiaochun; Murshed, Hasan; Bonnen, Mark D.; Garg, Amit K.; Stevens, Craig W.; Chang, Joe Y.; Jeter, Melinda D.; Mohan, Radhe; Cox, James D.; Komaki, Ritsuko

    2005-01-01

    Background and purpose: To evaluate the feasibility whether intensity-modulated radiotherapy (IMRT) can be used to reduce doses to normal lung than three-dimensional conformal radiotherapy (3DCRT) in treating distal esophageal malignancies. Patients and methods: Ten patient cases with cancer of the distal esophagus were selected for a retrospective treatment-planning study. IMRT plans using four, seven, and nine beams (4B, 7B, and 9B) were developed for each patient and compared with the 3DCRT plan used clinically. IMRT and 3DCRT plans were evaluated with respect to PTV coverage and dose-volumes to irradiated normal structures, with statistical comparison made between the two types of plans using the Wilcoxon matched-pair signed-rank test. Results: IMRT plans (4B, 7B, 9B) reduced total lung volume treated above 10 Gy (V 1 ), 20 Gy (V 2 ), mean lung dose (MLD), biological effective volume (V eff ), and lung integral dose (P 1 , 5% for V 2 , and 2.5 Gy for MLD. IMRT improved the PTV heterogeneity (P<0.05), yet conformity was better with 7B-9B IMRT plans. No clinically meaningful differences were observed with respect to the irradiated volumes of spinal cord, heart, liver, or total body integral doses. Conclusions: Dose-volume of exposed normal lung can be reduced with IMRT, though clinical investigations are warranted to assess IMRT treatment outcome of esophagus cancers

  15. Pulmonary function following adjuvant chemotherapy and radiotherapy for breast cancer and the issue of three-dimensional treatment planning

    International Nuclear Information System (INIS)

    Lind, P.A.R.M.; Glas, U.; Fornander, T.; Rosfors, S.; Bevegard, S.; Wennberg, B.

    1998-01-01

    Background and purpose: The frequency and grade of pulmonary complications following adjuvant radiotherapy for breast cancer are still debated. This study focuses on loss of pulmonary function. Materials and methods: We have measured the reduction of pulmonary function 5 months following radiotherapy in 144 node-positive stage II breast cancer patients by using pulmonary function tests. Results: No deterioration of pulmonary function was detected among the patients who were treated with local radiotherapy. On the contrary, there was a mean increase in diffusion capacity by 7% (P=0.004) following radiotherapy, which most likely was explained by the adjuvant chemotherapy administered prior to the baseline pulmonary function tests. Patients undergoing loco-regional radiotherapy showed a mean reduction in diffusion capacity by 5% (P<0.001) and in vital capacity by 3% (P=0.001). The subset of patients (9%) who were diagnosed with severe pulmonary complications needing cortisone treatment had significantly larger mean paired differences in vital capacity (-0.446 L, -15% (equivalent to 15 years of normal ageing or the loss of 3/4 of a lung lobe)) compared to the patients who were asymptomatic (-0.084 L) (P<0.05). When the effects of potential confounding factors and different radiotherapy techniques were tested on the reduction of pulmonary function by stepwise multiple regression analysis, a significant correlation was found only to loco-regional radiotherapy including the lower internal mammary lymph nodes. Conclusions: We conclude that a clinically important reduction of pulmonary function is seen in the subset of patients who are diagnosed with severe pulmonary complication following loco-regional radiotherapy for breast cancer. The results of this study warrant further studies based on individual lung dose volume histograms. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  16. The mechanisms of inter-effect about gene therapy and radiotherapy to tumor and the prospect of therapeutic alliance

    International Nuclear Information System (INIS)

    Zhao Yanzhi; Li Jin; Wang Qin; Mu Chuanjie

    2006-01-01

    The way about therapy include radio therapy and gene therapy in the recent years there are some improve about the therapy alliance, by the mechanism of improving the efficiency of the gene transfering, the recombination and conform of the DNA and induction the expression of the gene et. The radiotherapy can enhance the effect of the gene therapy. By the mechanism of improving of radiosensitivity some, reducing the radiation damage of radiotherapy, repairing the radiation impaired gene the gene therapy can enhance the effect of the radiotherapy. (authors)

  17. Consequential late effects after radiotherapy for prostate cancer - a prospective longitudinal quality of life study

    Directory of Open Access Journals (Sweden)

    Schaar Sandra

    2010-04-01

    Full Text Available Abstract Background To answer the question if and to which extent acute symptoms at the end and/or several weeks after radiotherapy can predict adverse urinary and gastrointestinal long-term quality of life (QoL. Methods A group of 298 patients has been surveyed prospectively before (time A, at the last day (B, two months after (C and >one year after (D radiotherapy using a validated questionnaire (Expanded Prostate Cancer Index Composite. A subgroup of 10% with the greatest urinary/bowel bother score decrease at time D was defined as patients with adverse long-term QoL. Results Subgroup and correlation analyses could demonstrate a strong dependence of urinary/bowel QoL after radiotherapy on urinary/bowel QoL before radiotherapy. In contrast to absolute scores, QoL score changes (relative to baseline scores did not correlate with pretreatment scores. Long-term changes could be well predicted by acute changes. Patients reporting great/moderate bother with urinary/bowel problems at time C reported to have great/moderate bother at time D in ≥ 50%, respectively. In a multivariate analysis of factors for adverse long-term urinary and bowel QoL, score changes at time C were found to be independent predictors, respectively. Additionally, QoL changes at time B were independently predictive for adverse long-term bowel QoL. Conclusions Consequential late effects play a major role after radiotherapy for prostate cancer. Patients with greater and particularly longer non-healing acute toxicity are candidates for closer follow-up and possible prophylactic actions to reduce a high probability of long-term problems.

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

    International Nuclear Information System (INIS)

    Umbarkar, Rahul B.; Singh, Sanjay; Singh, K.K.; Shrivastava, Rajeev; Sarje, Mukund; Supe, Sanjay S.

    2008-01-01

    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)

  19. Preventive Effect of Glycyrrhiza Glabra Extract on Oral Mucositis in Patients under Head and Neck Radiotherapy: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Shamsolmolok Najafi

    2017-12-01

    Full Text Available Objectives: About two-thirds of cancer patients undergo radiotherapy. Oral mucositis represents a major complication of radiotherapy, causing morbidity and mortality and decreasing the quality of life of patients. This study aimed to assess the preventive effect of Glycyrrhiza aqueous extract on oral mucositis in cancer patients under head and neck radiotherapy.Materials and Methods: In this double-blind clinical trial, 37 head and neck cancer patients were divided into intervention (n=19 group receiving Glycyrrhiza aqueous extract and control (n=18 group receiving placebo. Patients in the test group used Glycyrrhiza aqueous extract topically twice a day from the first day of starting radiotherapy until the end of the second week. Patients were examined in the first day of radiotherapy for any type of wound before treatment and those with oral ulcers before radiotherapy were excluded from the study. The grade of mucositis was determined using the classification by the World Health Organization. ANCOVA was performed to assess any difference between the two groups with regard to oral mucosal irritation and wound size after the intervention while controlling for the covariates such as sex and age.Results: Significant differences were found in the maximum grade of mucositis and oral mucosal irritation between the intervention and control groups (P<0.001.Conclusions: This study showed that aqueous extract of Glycyrrhiza can be effective for decreasing the severity of oral mucositis in head and neck cancer patients undergoing radiotherapy.

  20. 3-D conformal radiotherapy of localized prostate cancer: A subgroup analysis of rectoscopic findings prior to radiotherapy and acute/late rectal side effects

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  1. Dose-volume analysis of hypothyroidism in patients irradiated to the neck

    International Nuclear Information System (INIS)

    Te, Vuong; Liu, Mitchell C.C.; Parker, William; Curtin-Savard, Arthur J.; Clark, Brenda

    1997-01-01

    Purpose: To determine if the incidence of hypothyroidism in patients who have received radiation therapy to the neck region has any relationship with the total dose to the thyroid and volume of thyroid irradiation. Methods and Materials: From 1988 to 1996, TSH levels were measured at regular intervals of every 3 to 6 months in 528 patients with head and neck cancers or lymphomas (Hodgkin and non-Hodgkin) who had received radiation therapy to the neck region. Hypothyroidism was defined by TSH of ≥ 5 (normal range: 0.5 - 4mU/L). Medical charts, radiotherapy charts, treatment planning films, dosimetry and CT scans/MRI were reviewed. Thyroid volume was determined utilizing treatment planning films and CT scans/MRI. Four hundred and six patients had normal TSH prior to radiation and sufficient information to be eligible for analysis. There were 264 (65%) male and 142 (35%) female, median age was 59 yr (range: 12 - 85). Median follow-up was 39.5 months (range: 1 - 289 months). Results: Out of the 406 eligible patients, 152 (37%) had developed hypothyroidism. The actuarial incidence of hypothyroidism at 1 yr, 3 yr and 5 yr are 9.1%, 29% and 38.5%, respectively. Analysis of volume effect and dose effect are as follows: When the radiation dose to the thyroid and the volume of thyroid irradiated are analyzed together, the group of patients who received ≥ 60Gy to half of thyroid or received ≥ 30Gy to the whole thyroid has increased risk of developing hypothyroidism as compared to those receiving <60Gy to half the thyroid or <30Gy to the whole thyroid (p=.0001). Conclusions: The actuarial incidence of hypothyroidism at 5 year in patients who had received radiation to the neck is 38.5%. Patients who received ≥ 60Gy to half the thyroid or received ≥ 30Gy to the whole thyroid are at higher risk of developing hyperthyroidism

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

    Directory of Open Access Journals (Sweden)

    SUN Jing

    2016-06-01

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

  3. Conformal radiation therapy of localized prostate cancer: acute tolerance and early evaluation of effectiveness

    International Nuclear Information System (INIS)

    Zierhut, D.; Flentje, M.; Sroka-Perez, G.; Rudat, V.; Engenhart-Cabillic, R.; Wannenmacher, M.

    1997-01-01

    Aim: In a prospective trial early effectiveness and acute toxicity of conformal 3D-planned radiotherapy for localized prostate cancer was quantified using dose-volume-histogramms and evaluated with respect of treatment technique. Results: Eleven patients (of 32) had none, 15 mild (RTOG grade 1) and 6 moderate symptoms (RTOG grade 2, mainly diarrhoea, dysuria and polyuria). Acute complications leading to treatment interruption did not occur. In 16 patients symptoms disappeared within 6 weeks after radiotherapy. Only 2 men had symptoms which lasted longer than 3 months and were endoscopically examined. Up to now no late complications were detected. Incidence and severity of toxicity was significantly (p [de

  4. Cytotoxic effect of Erythroxylum suberosum combined with radiotherapy in head and neck cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Taysa B.C.; Torres, Hianne M.; Yamamoto-Silva, Fernanda Paula; Silva, Maria Alves G. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Escola de Odontologia; Elias, Silvia T.; Silveira, Damaris; Magalhaes, Perola O.; Lofrano-Porto, Adriana; Guerra, Eliete N.S., E-mail: elieteneves@unb.br [Universidade de Brasilia (UnB), Brasilia, DF (Brazil). Faculdade de Ciencias da Saude

    2016-01-15

    The mouth and oropharynx cancer is the 6{sup th} most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as 'cabelo-de-negro'. The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas. (author)

  5. Cytotoxic effect of Erythroxylum suberosum combined with radiotherapy in head and neck cancer cell lines

    International Nuclear Information System (INIS)

    Macedo, Taysa B.C.; Torres, Hianne M.; Yamamoto-Silva, Fernanda Paula; Silva, Maria Alves G.; Elias, Silvia T.; Silveira, Damaris; Magalhaes, Perola O.; Lofrano-Porto, Adriana; Guerra, Eliete N.S.

    2016-01-01

    The mouth and oropharynx cancer is the 6 th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as 'cabelo-de-negro'. The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas. (author)

  6. Effect of probiotics on the fecal microflora after radiotherapy: A pilot study

    Directory of Open Access Journals (Sweden)

    J Timko

    2013-01-01

    Full Text Available Background and Aim : The development of gastrointestinal symptoms following pelvic radiotherapy depends on morphological and functional modifications of the intestinal epithelium after radiation. The aim of this study was to evaluate and compare the effects of preventive administration of the preparation ′′5′′ Strain Dophilus and Hylak on the fecal microflora after radiotherapy in patients during radiotherapy. Materials and Methods : Fourteen patients were randomly selected and subdivided into two groups: The first group was administered ′′5′′ Strain Dophilus (L Group and the second group was administered Hylak (H Group. Radiation was delivered by a Cobalt 60 unit by using the four field box technique. The doses were divided into 2 Gy per day over 5 to 7 weeks to give the total cumulative dose of 50 Gy (2 Gy/day. High risk patients (e.g., patients with prostate cancer, received dosage 65 67 Gy (2 Gy/day. Results : Both experimental and clinical studies have shown that probiotics can effectively modulate intestinal inflammation by altering the composition and the metabolic and functional properties of gut indigenous flora. Conclusions : Many bacteria were found to be sensitive to irradiation. It would be necessary to check the possible effects of cytostatics on bacteria in larger studies.

  7. Adjuvant single-fraction radiotherapy is safe and effective for intractable keloids

    International Nuclear Information System (INIS)

    Song, Changhoon; Wu, Honggyun; Chang, Hak; Kim, Il Han; Ha, Sung W.

    2014-01-01

    The aim of this study was to assess the feasibility and efficacy of high-dose, single-fraction electron beam radiotherapy for therapy-resistant keloids. Before 2010, intractable keloids were treated at our institution with post-operative irradiation of 6-15 Gy in 3-5 fractionations. For convenience and cost effectiveness, we have changed our treatment protocol to high-dose single-fraction radiotherapy. A total of 12 patients with 16 keloid lesions were treated from January 2010 to January 2013 in our department. A 10-Gy dose of electron irradiation was given within 72 h of the surgical excision. The mean follow-up period was 20 months. Treatments were well tolerated, and there was no recurrence in any of the patients. Severe adverse effects were not observed. Surgical excision of the keloid, followed by immediate, single-fraction, high-dose radiotherapy, is both safe and effective in preventing recurrence of therapy-resistant keloids. (author)

  8. Dose-volume analysis for quality assurance of interstitial brachytherapy for breast cancer

    International Nuclear Information System (INIS)

    Vicini, Frank A.; Kestin, Larry L.; Edmundson, Gregory K.; Jaffray, David A.; Wong, John W.; Kini, Vijay R.; Chen, Peter Y.; Martinez, Alvaro A.

    1999-01-01

    Purpose/Objective: The use of brachytherapy in the management of breast cancer has increased significantly over the past several years. Unfortunately, few techniques have been developed to compare dosimetric quality and target volume coverage concurrently. We present a new method of implant evaluation that incorporates computed tomography-based three-dimensional (3D) dose-volume analysis with traditional measures of brachytherapy quality. Analyses performed in this fashion will be needed to ultimately assist in determining the efficacy of breast implants. Methods and Materials: Since March of 1993, brachytherapy has been used as the sole radiation modality after lumpectomy in selected protocol patients with early-stage breast cancer treated with breast-conserving therapy. Eight patients treated with high-dose-rate (HDR) brachytherapy who had surgical clips outlining the lumpectomy cavity and underwent computed tomography (CT) scanning after implant placement were selected for this study. For each patient, the postimplant CT dataset was transferred to a 3D treatment planning system. The lumpectomy cavity, target volume (lumpectomy cavity plus a 1-cm margin), and entire breast were outlined on each axial slice. Once all volumes were entered, the programmed HDR brachytherapy source positions and dwell times were imported into the 3D planning system. Using the tools provided by the 3D planning system, the implant dataset was then registered to the visible implant template in the CT dataset. The distribution of the implant dose was analyzed with respect to defined volumes via dose-volume histograms (DVH). Isodose surfaces, the dose homogeneity index, and dosimetric coverage of the defined volumes were calculated and contrasted. All patients received 32 Gy to the entire implanted volume in 8 fractions of 4 Gy over 4 days. Results: Three-plane implants were used for 7 patients and a two-plane implant for 1 patient. The median number of needles per implant was 16.5 (range

  9. Side effects of radiotherapy in breast cancer patients : The Internet as an information source.

    Science.gov (United States)

    Janssen, S; Käsmann, L; Fahlbusch, F B; Rades, D; Vordermark, D

    2018-02-01

    Breast cancer is the most common cancer type among women necessitating adjuvant radiotherapy. As the Internet has become a major source of information for cancer patients, this study aimed to evaluate the quality of websites giving information on side effects of radiotherapy for breast cancer patients. A patients' search for the English terms "breast cancer - radiotherapy - side effects" and the corresponding German terms "Brustkrebs - Strahlentherapie - Nebenwirkungen" was carried out twice (5 months apart) using the search engine Google. The first 30 search results each were evaluated using the validated 16-question DISCERN Plus instrument, the Health on the Net Code of Conduct (HONcode) certification and the Journal of the American Medical Association (JAMA) benchmark criteria. The overall quality (DISCERN score) of the retrieved websites was further compared to queries via Bing and Yahoo search engines. The DISCERN score showed a great range, with the majority of websites ranking fair to poor. Significantly superior results were found for English websites, particularly for webpages run by hospitals/universities and nongovernmental organizations (NGO), when compared to the respective German categories. In general, only a minority of websites met all JAMA benchmarks and was HONcode certified (both languages). We did not determine a relevant temporal change in website ranking among the top ten search hits, while significant variation occurred thereafter. Mean overall DISCERN score was similar between the various search engines. The Internet can give breast cancer patients seeking information on side effects of radiotherapy an overview. However, based on the currently low overall quality of websites and the lack of transparency for the average layperson, we emphasize the value of personal contact with the treating radio-oncologist in order to integrate and interpret the information found online.

  10. Side effects of radiotherapy in breast cancer patients. The Internet as an information source

    International Nuclear Information System (INIS)

    Janssen, S.; Kaesmann, L.; Rades, D.; Fahlbusch, F.B.; Vordermark, D.

    2018-01-01

    Breast cancer is the most common cancer type among women necessitating adjuvant radiotherapy. As the Internet has become a major source of information for cancer patients, this study aimed to evaluate the quality of websites giving information on side effects of radiotherapy for breast cancer patients. A patients' search for the English terms ''breast cancer - radiotherapy - side effects'' and the corresponding German terms ''Brustkrebs - Strahlentherapie - Nebenwirkungen'' was carried out twice (5 months apart) using the search engine Google. The first 30 search results each were evaluated using the validated 16-question DISCERN Plus instrument, the Health on the Net Code of Conduct (HONcode) certification and the Journal of the American Medical Association (JAMA) benchmark criteria. The overall quality (DISCERN score) of the retrieved websites was further compared to queries via Bing and Yahoo search engines. The DISCERN score showed a great range, with the majority of websites ranking fair to poor. Significantly superior results were found for English websites, particularly for webpages run by hospitals/universities and nongovernmental organizations (NGO), when compared to the respective German categories. In general, only a minority of websites met all JAMA benchmarks and was HONcode certified (both languages). We did not determine a relevant temporal change in website ranking among the top ten search hits, while significant variation occurred thereafter. Mean overall DISCERN score was similar between the various search engines. The Internet can give breast cancer patients seeking information on side effects of radiotherapy an overview. However, based on the currently low overall quality of websites and the lack of transparency for the average layperson, we emphasize the value of personal contact with the treating radio-oncologist in order to integrate and interpret the information found online. (orig.) [de

  11. Cardiovascular effects after low-dose exposure and radiotherapy: what research is needed?

    Energy Technology Data Exchange (ETDEWEB)

    Wondergem, Jan [International Atomic Energy Agency, Applied Radiation Biology and Radiotherapy Section, Division of Human Health, Department of Nuclear Sciences and Applications, Vienna (Austria); Boerma, Marjan [University of Arkansas for Medical Sciences, Division of Radiation Health, Department of Pharmaceutical Sciences, Little Rock, AR (United States); Kodama, Kazunori [Radiation Effects Research Foundation, Hiroshima (Japan); Stewart, Fiona A. [Netherlands Cancer Institute, Biological Stress Response (H3), Amsterdam (Netherlands); Trott, Klaus R.

    2013-11-15

    The authors of this report met at the Head Quarter of the International Atomic Energy Agency (IAEA) in Vienna, Austria, on 2-4 July 2012, for intensive discussions of an abundance of original publications on new epidemiological studies on cardiovascular effects after low-dose exposure and radiotherapy and radiobiological experiments as well as several comprehensive reviews that were published since the previous meeting by experts sponsored by the IAEA in June 2006. The data necessitated a re-evaluation of the situation with special emphasis on the consequences current experimental and clinical data may have for clinical oncology/radiotherapy and radiobiological research. The authors jointly arrived at the conclusions and recommendations presented here. (orig.)

  12. Effects of low dose radiation on antioxidant enzymes after radiotherapy of tumor-bearing mice

    International Nuclear Information System (INIS)

    Li Jin; Gao Gang; Wang Qin; Tang Weisheng; Liu Xiaoqiu; Wang Zhiquan

    2005-01-01

    Objective: To search for effects of low dose radiation on the activities of antioxidant enzymes after radiotherapy of tumor-bearing mice. Methods: Superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT) were all determined by chemical colorimetry. Results: Low dose radiation increase the activities of antioxidant enzymes superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT) in serum of tumor-bearing mice more markedly than those in the unirradiated controls. The activities of antioxidant enzymes SOD, GST, CAT in serum of tumor-bearing mice (d 5 , d 3 ) irradiated with 5cGy 6h before 2.0 Gy radiation are obviously higher than those of the group (c 3 , c 5 ) given with radiotherapy only. Conclusion: The increase in the activities of antioxidant enzymes in serum of tumor-bearing mice triggered by low dose radiation could partly contribute to the protective mechanism. (authors)

  13. Cardiovascular effects after low-dose exposure and radiotherapy: what research is needed?

    International Nuclear Information System (INIS)

    Wondergem, Jan; Boerma, Marjan; Kodama, Kazunori; Stewart, Fiona A.; Trott, Klaus R.

    2013-01-01

    The authors of this report met at the Head Quarter of the International Atomic Energy Agency (IAEA) in Vienna, Austria, on 2-4 July 2012, for intensive discussions of an abundance of original publications on new epidemiological studies on cardiovascular effects after low-dose exposure and radiotherapy and radiobiological experiments as well as several comprehensive reviews that were published since the previous meeting by experts sponsored by the IAEA in June 2006. The data necessitated a re-evaluation of the situation with special emphasis on the consequences current experimental and clinical data may have for clinical oncology/radiotherapy and radiobiological research. The authors jointly arrived at the conclusions and recommendations presented here. (orig.)

  14. Experimental study on anti-tumor effect of pcEgr-IFNγ gene-radiotherapy

    International Nuclear Information System (INIS)

    Wu Congmei; Li Xiuyi; Liu Shuzheng

    2001-01-01

    Objective: To study the anti-tumor effect of IFN γ gene-radiotherapy to murine melanoma and its immunologic mechanism. Methods: pcEgr-IFNγ plasmids were injected locally into tumor, and 36 hours later, the tumors were given 20 Gy X-ray irradiation. Tumor growth at different time, IFN γ expression 3 days later and immunologic indexes 15 days later were detected. Results: At 3-15 days after pcEgr-IFNγ gene-radiotherapy, the tumor growth rate was lower than that of irradiation alone group. It was also lower than that of gene therapy alone group and control plasmid combined with X-ray irradiation group significantly. Day 3 tumor IFN γ expression was higher than that of plasmid treatment alone group. NK activity, IL-2 and IFN γ secretion activities were higher than those of gene therapy alone and irradiation alone groups significantly. Conclusion: The antitumor effect of IFN γ gene-radiotherapy is better than that of either of them applied solely. Its mechanism might be concerned with the higher expression of IFN γ induced by irradiation in tumors and activation of anti-tumor immunologic functions

  15. Effect of MLC Leaf Width and PTV Margin on the Treatment Planning of Intensity-Modulated Stereotactic Radiosurgery (IMSRS) or Radiotherapy (IMSRT)

    International Nuclear Information System (INIS)

    Chang Jenghwa; Yenice, Kamil M.; Jiang Kailiu; Hunt, Margie; Narayana, Ashwatha

    2009-01-01

    We studied the effect of MLC (multileaf collimator) leaf width and PTV (planning target volume) margin on treatment planning of intensity modulated stereotactic radiosurgery (IMSRS) or radiotherapy (IMSRT). Twelve patients previously treated with IMSRS/IMSRT were retrospectively planned with 5- and 3-mm MLC leaf widths and 3- and 2-mm PTV margins using the already contoured clinical target volume and critical structures. The same beam arrangement, planning parameters, and optimization method were used in each of the 4 plans for a given patient. Each plan was normalized so that the prescription dose covered at least 99% of the PTV. Plan indices - D mean (mean dose), conformity index (CI), V 70 (volume receiving ≥ 70% of the prescription dose), and V 50 (volume receiving ≥ 50% of the prescription dose) - were calculated from the dose-volume histograms (DVHs) of the PTV, normal tissue, and organs at risk (OARs). Hypothesis testing was performed on the mean ratios of plan indices to determine the statistical significance of the relative differences. The PTV was well covered for all plans, as no significant differences were observed for D 95 , V 95 , D max , D min , and D mean of the PTV. The irradiated volume was ∼23% smaller when 2-mm instead of 3-mm PTV margin was used, but it was only reduced by ∼6% when the MLC leaf width was reduced from 5 mm to 3 mm. For normal tissue and brainstem, V 70 , V 50 , and D mean were reduced more effectively by a decrease in MLC width, while D mean of optic nerve and chiasm were more sensitive to a change in PTV margin. The DVH statistics for the PTV and normal structures from the treatment plan with 5-mm MLC and 2-mm PTV margin were equal to those with 3-mm MLC and 3-mm PTV margin. PTV margin reduction is more effective in sparing the normal tissue and OARs than a reduction in MLC leaf width. For IMSRS, where highly accurate setup and small PTV margins are routinely employed, the use of 5-mm MLC is therefore less desirable.

  16. Late Side Effects and Quality of Life After Radiotherapy for Rectal Cancer

    International Nuclear Information System (INIS)

    Bruheim, Kjersti; Guren, Marianne G.; Skovlund, Eva; Hjermstad, Marianne J.; Dahl, Olav; Frykholm, Gunilla; Carlsen, Erik; Tveit, Kjell Magne

    2010-01-01

    Purpose: There is little knowledge on long-term morbidity after radiotherapy (50 Gy) and total mesorectal excision for rectal cancer. Therefore, late effects on bowel, anorectal, and urinary function, and health-related quality of life (QoL), were studied in a national cohort (n = 535). Methods and Materials: All Norwegian patients who received pre- or postoperative (chemo-)radiotherapy for rectal cancer from 1993 to 2003 were identified. Patients treated with surgery alone served as controls. Patients were without recurrence or metastases. Bowel and urinary function was scored with the LENT SOMA scale and the St. Marks Score for fecal incontinence and QoL with the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30). Results: Median time since surgery was 4.8 years. Radiation-treated (RT+) patients (n = 199) had increased bowel frequency compared with non-radiation-treated (RT-) patients (n = 336); 19% vs. 6% had more than eight daily bowel movements (p < 0.001). In patients without stoma, a higher proportion of RT+ (n = 69) compared with RT- patients (n = 240), were incontinent for liquid stools (49% vs. 15%, p < 0.001), needed a sanitary pad (52% vs. 13%, p < 0.001), and lacked the ability to defer defecation (44% vs. 16%, p < 0.001). Daily urinary incontinence occurred more frequently after radiotherapy (9% vs. 2%, p = 0.001). Radiation-treated patients had worse social function than RT- patients, and patients with fecal or urinary incontinence had impaired scores for global quality of life and social function (p < 0.001). Conclusions: Radiotherapy for rectal cancer is associated with considerable long-term effects on anorectal function, especially in terms of bowel frequency and fecal incontinence. RT+ patients have worse social function, and fecal incontinence has a negative impact on QoL.

  17. Calculation of normal tissue complication probability and dose-volume histogram reduction schemes for tissues with a critical element architecture

    International Nuclear Information System (INIS)

    Niemierko, Andrzej; Goitein, Michael

    1991-01-01

    The authors investigate a model of normal tissue complication probability for tissues that may be represented by a critical element architecture. They derive formulas for complication probability that apply to both a partial volume irradiation and to an arbitrary inhomogeneous dose distribution. The dose-volume isoeffect relationship which is a consequence of a critical element architecture is discussed and compared to the empirical power law relationship. A dose-volume histogram reduction scheme for a 'pure' critical element model is derived. In addition, a point-based algorithm which does not require precomputation of a dose-volume histogram is derived. The existing published dose-volume histogram reduction algorithms are analyzed. The authors show that the existing algorithms, developed empirically without an explicit biophysical model, have a close relationship to the critical element model at low levels of complication probability. However, it is also showed that they have aspects which are not compatible with a critical element model and the authors propose a modification to one of them to circumvent its restriction to low complication probabilities. (author). 26 refs.; 7 figs

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

    International Nuclear Information System (INIS)

    Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seyed Rabie; Nikoofar, Alireza; Edraki, Hamid Reza; Kazemnejad, Anoshirvan

    2012-01-01

    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 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 may result from the increase in intrathyroidal flow.

  19. Conformal irradiation of the prostate: estimating long-term rectal bleeding risk using dose-volume histograms

    International Nuclear Information System (INIS)

    Hartford, Alan C.; Niemierko, Andrzej; Adams, Judith A.; Urie, Marcia M.; Shipley, William U.

    1996-01-01

    Purpose: Dose-volume histograms (DVHs) may be very useful tools for estimating probability of normal tissue complications (NTCP), but there is not yet an agreed upon method for their analysis. This study introduces a statistical method of aggregating and analyzing primary data from DVHs and associated outcomes. It explores the dose-volume relationship for NTCP of the rectum, using long-term data on rectal wall bleeding following prostatic irradiation. Methods and Materials: Previously published data were reviewed and updated on 41 patients with Stages T3 and T4 prostatic carcinoma treated with photons followed by perineal proton boost, including dose-volume histograms (DVHs) of each patient's anterior rectal wall and data on the occurrence of postirradiation rectal bleeding (minimum FU > 4 years). Logistic regression was used to test whether some individual combination of dose and volume irradiated might best separate the DVHs into categories of high or low risk for rectal bleeding. Further analysis explored whether a group of such dose-volume combinations might be superior in predicting complication risk. These results were compared with results of the 'critical volume model', a mathematical model based on assumptions of underlying radiobiological interactions. Results: Ten of the 128 tested dose-volume combinations proved to be 'statistically significant combinations' (SSCs) distinguishing between bleeders (14 out of 41) and nonbleeders (27 out of 41), ranging contiguously between 60 CGE (Cobalt Gray Equivalent) to 70% of the anterior rectal wall and 75 CGE to 30%. Calculated odds ratios for each SSC were not significantly different across the individual SSCs; however, analysis combining SSCs allowed segregation of DVHs into three risk groups: low, moderate, and high. Estimates of probabilities of normal tissue complications (NTCPs) based on these risk groups correlated strongly with observed data (p = 0.003) and with biomathematical model-generated NTCPs

  20. First impressions of 3D visual tools and dose volume histograms for plan evaluation

    International Nuclear Information System (INIS)

    Rattray, G.; Simitcioglu, A.; Parkinson, M.; Biggs, J.

    1999-01-01

    Converting from 2D to 3D treatment planning offers numerous challenges. The practices that have evolved in the 2D environment may not be applicable when translated into the 3D environment. One such practice is the methods used to evaluate a plan. In 2D planning a plane by plane comparison method is generally practiced. This type of evaluation method would not be appropriate for plans produced by a 3D planning system. To this end 3D dose displays and Dose Volume Histograms (DVHs) have been developed to facilitate the evaluation of such plans. A survey was conducted to determine the impressions of Radiation Therapists as they used these tools for the first time. The survey involved comparing a number of plans for a small group of patients and selecting the best plan for each patient. Three evaluation methods were assessed. These included the traditional plane by plane, 3D dose display, and DVHs. Those surveyed found the DVH to be the easiest of the three methods to use, with the 3D display being the next easiest. Copyright (1999) Blackwell Science Pty Ltd

  1. Equivalent uniform dose concept evaluated by theoretical dose volume histograms for thoracic irradiation.

    Science.gov (United States)

    Dumas, J L; Lorchel, F; Perrot, Y; Aletti, P; Noel, A; Wolf, D; Courvoisier, P; Bosset, J F

    2007-03-01

    The goal of our study was to quantify the limits of the EUD models for use in score functions in inverse planning software, and for clinical application. We focused on oesophagus cancer irradiation. Our evaluation was based on theoretical dose volume histograms (DVH), and we analyzed them using volumetric and linear quadratic EUD models, average and maximum dose concepts, the linear quadratic model and the differential area between each DVH. We evaluated our models using theoretical and more complex DVHs for the above regions of interest. We studied three types of DVH for the target volume: the first followed the ICRU dose homogeneity recommendations; the second was built out of the first requirements and the same average dose was built in for all cases; the third was truncated by a small dose hole. We also built theoretical DVHs for the organs at risk, in order to evaluate the limits of, and the ways to use both EUD(1) and EUD/LQ models, comparing them to the traditional ways of scoring a treatment plan. For each volume of interest we built theoretical treatment plans with differences in the fractionation. We concluded that both volumetric and linear quadratic EUDs should be used. Volumetric EUD(1) takes into account neither hot-cold spot compensation nor the differences in fractionation, but it is more sensitive to the increase of the irradiated volume. With linear quadratic EUD/LQ, a volumetric analysis of fractionation variation effort can be performed.

  2. Brachytherapy dose-volume histogram computations using optimized stratified sampling methods

    International Nuclear Information System (INIS)

    Karouzakis, K.; Lahanas, M.; Milickovic, N.; Giannouli, S.; Baltas, D.; Zamboglou, N.

    2002-01-01

    A stratified sampling method for the efficient repeated computation of dose-volume histograms (DVHs) in brachytherapy is presented as used for anatomy based brachytherapy optimization methods. The aim of the method is to reduce the number of sampling points required for the calculation of DVHs for the body and the PTV. From the DVHs are derived the quantities such as Conformity Index COIN and COIN integrals. This is achieved by using partial uniform distributed sampling points with a density in each region obtained from a survey of the gradients or the variance of the dose distribution in these regions. The shape of the sampling regions is adapted to the patient anatomy and the shape and size of the implant. For the application of this method a single preprocessing step is necessary which requires only a few seconds. Ten clinical implants were used to study the appropriate number of sampling points, given a required accuracy for quantities such as cumulative DVHs, COIN indices and COIN integrals. We found that DVHs of very large tissue volumes surrounding the PTV, and also COIN distributions, can be obtained using a factor of 5-10 times smaller the number of sampling points in comparison with uniform distributed points

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

    International Nuclear Information System (INIS)

    Yao Zhijun; Cao Yongzhen; Zhang Wenxue; Liang Feng

    2012-01-01

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

  4. A comparison of morbidity following conformal versus intensity-modulated radiotherapy for urinary bladder cancer.

    Science.gov (United States)

    Søndergaard, Jimmi; Holmberg, Mats; Jakobsen, Annette Ross; Agerbæk, Mads; Muren, Ludvig Paul; Høyer, Morten

    2014-10-01

    In radiotherapy (RT) of urinary bladder cancer, the use of intensity-modulated RT (IMRT) opens for sparing of considerable intestinal volumes. The purpose of the present study was to investigate the acute and late toxicities following either conformal RT (CRT) or IMRT for bladder cancer, and to correlate the toxicities to dose-volume parameters. The study included 116 consecutively treated patients with muscle-invasive bladder cancer who received either CRT (n = 66) or IMRT (n = 50) during 2007-2010. Acute side effects were retrospectively collected whereas late effects were assessed by a cross-sectional evaluation by telephone interview of 44 recurrence-free patients. Acute and late toxicities were scored according to the Common Terminology Criteria for Adverse Event (CTCAE) version 3.0. Acute diarrhoea grade ≥ 2 was more frequent in patients treated by CRT (56%) compared to IMRT (30%) (p = 0.008). Logistic regression analysis showed a correlation between acute diarrhoea and bowel cavity dose-volume parameters in the 10-50 Gy range. Severe late toxicity (grade ≥ 3) was recorded in 10% of the total cohort, with no statistical difference between the IMRT and CRT groups. Patients treated with IMRT for bladder cancer had significantly less acute diarrhoea compared to those treated with CRT, but there was no significant difference in late morbidity between the groups. The risk of acute diarrhoea was related to the volume of bowel irradiated.

  5. 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.

  6. Effects of the association of chemotherapy and radiotherapy on normal mouse skin

    International Nuclear Information System (INIS)

    Guigon, M.; Frindel, E.; Tubiana, M.; Hewitt, J.

    1978-01-01

    The effects of an association of chemotherapy and radiotherapy on the skin of mice were studied. The following drugs were tested; hydroxyurea, Methotrexate, and Bleomycin; they were injected at various times before irradiation. When hydroxyurea was injected 15 min before irradiation, the early and late cutaneous reactions were significantly lower than with irradiation alone. This protective effect corresponds to about 500 rad for an irradiation dose of 2500 rad. In the other protocols, we observed either no increase of the effect as a result of adjuvant chemotherapy (Methotrexate) or slightly increased reactions

  7. Early and late effects of local high dose radiotherapy of the brain on memory and attention

    International Nuclear Information System (INIS)

    Duchstein, S.; Gademann, G.; Peters, B.

    2003-01-01

    Early and Late Effects of Local High Dose Radiotherapy of the Brain on Memory and Attention Background: Stereotactic radiotherapy of benign tumors of the base of skull shows excellent tumor control and long survival. Aim is to study the impact of high dose radiation therapy on functions of memory and attention over time. Patients and Methods: 21 patients (age 42 ± 11 years) with tumors of the base of skull (meningiomas, pituitary gland adenomas) were treated by fractionated stereotactic radiotherapy (mean total dose 56,6 Gy/1,8 Gy). Comprehensive neuropsychological tests and MRI brain scans were performed before, 3, 9 and 21 months after therapy. 14 healthy volunteers were tested in parallel at baseline. In the follow-ups patients were their own controls. Results: In pretreatment tests there were significantly worse test results in comparison to the control group in ten of 32 tests. In postradiation tests only few changes were found in the early-delayed period and not much difference was seen in comparison to the baseline tests. In MRI scans tumor recurrences or radiation induced changes were not found. Conclusion: Radiation with high local doses in target volume extremely close to sensitive brain structures like temporal lobes did not induce significant decline of cognitive functions. (orig.) [de

  8. The Effect of Breast Reconstruction Prosthesis on Photon Dose Distribution in Breast Cancer Radiotherapy

    Directory of Open Access Journals (Sweden)

    fatemeh sari

    2017-12-01

    Full Text Available Introduction: Siliconeprosthetic implants are commonlyutilizedfor tissue replacement and breast augmentation after mastectomy. On the other hand, some patients require adjuvant radiotherapy in order to preventlocal-regional recurrence and increment ofthe overall survival. In case of recurrence, the radiation oncologist might have to irradiate the prosthesis.The aim of this study was to evaluate the effect of silicone prosthesis on photon dose distribution in breast radiotherapy. Materials and Methods: The experimental dosimetry was performed using theprosthetic breast phantom and the female-equivalent mathematical chest phantom. A Computerized Tomographybased treatment planning was performedusing a phantom and by CorePlan Treatment Planning System (TPS. For measuring the absorbed dose, thermoluminescent dosimeter(TLD chips (GR-207A were used. Multiple irradiations were completed for all the TLD positions, and the dose absorbed by the TLDs was read by a lighttelemetry (LTM reader. Results: Statistical comparisons were performed between the absorbed dosesassessed by the TLDs and the TPS calculations forthe same sites. Our initial resultsdemonstratedanacceptable agreement (P=0.064 between the treatment planning data and the measurements. The mean difference between the TPS and TLD resultswas 1.99%.The obtained findings showed that radiotherapy is compatible withsilicone gel prosthesis. Conclusion: It could be concludedthat the siliconbreast prosthesis has no clinicallysignificant effectondistribution of a 6 MV photon beam for reconstructed breasts.

  9. Long-term effects of radiotherapy on taste and salivary function in man

    International Nuclear Information System (INIS)

    Mossman, K.; Shatzman, A.; Chencharick, J.

    1982-01-01

    The long-term effects of radiotherapy on taste and salivary function were studied in 13 patients treated by radiation 1-7 years previously for tumors of the head and neck. Taste function was studied quantitatively using a standard forced choice, three-stimulus-drop technique for the determination of detection and recognition thresholds and a forced-scaling technique for the determination of taste intensity reponsiveness. Parotid salivary function was quantitatively evaluated by determination of flow rate and protein secretion rate. Nine of the 13 patients studied (69%) had measurable taste loss; every patient who had radiotherapy including the parotid glands had measurable salivary dysfunction. Our results demonstrate that curative courses of radiotherapy for tumors of the head and neck may result in long-term changes in taste and salivary function. From the present study, the maximum tolerance doses resulting in a 50% complication rate 5 years after treatment (TD 50/5) are estimated to be 40-65 Gy for xerostomia and 50-65 Gy for taste loss. Therefore, in a standard treatment regimen for tumors of the head and neck, with curative intent, gustatory and salivary gland tissues frequently sustain maximum tolerance injury

  10. Stereotactic Body Radiotherapy for Centrally Located Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yuming WAN

    2018-05-01

    Full Text Available A few study has proven that about 90% of local control rates might be benefit from stereotactic body radiotherapy (SBRT for patients with medically inoperable stage I non-small cell lung cancer (NSCLC, it is reported SBRT associated overall survival and tumor specific survival is comparable with those treated with surgery. SBRT has been accepted as the first line treatment for inoperable patients with peripheral located stage I NSCLC. However, the role of SBRT in centrally located lesions is controversial for potential toxic effects from the adjacent anatomical structure. This paper will review the definition, indication, dose regimens, dose-volume constraints for organs at risk, radiation technology, treatment side effect of centrally located NSCLC treated with SBRT and stereotactic body proton therapy.

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Bora Uysal

    2013-03-01

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

  13. The effect of dental management for maintaining dental health in patients with head and neck cancer after radiotherapy

    International Nuclear Information System (INIS)

    Katsura, Kouji; Sasai, Keisuke; Sato, Katsuro; Hayashi, Takafumi; Goto, Sanae; Tomita, Masahiko; Matsuyama, Hiroshi

    2009-01-01

    The purpose of this study was to evaluate the significance of our dental management protocol by observing the chronological change of dental health of head and neck radiotherapy patients. Fifty-two head and neck radiotherapy patients who had received dental management to prevent and/or alleviate their oral complications were enrolled in this study. They were followed for three or more years after radiotherapy. We divided them into three groups according to the timing of the start of dental management; Pre, Mid and Post. The chronological changes of dental status (DMFT and the number of tooth extractions) and osteoradionecrosis were investigated for three to five years. The increase in the DMFT index of the Pre and Mid groups was reduced to less than 2 by introducing our dental management protocol. On the contrary, the number of unavoidable tooth extractions following radiotherapy was the least in the Pre group. The incidence rates of osteoradionecrosis of the mandible in the Pre, Mid and Post groups were 6.5%, 18.0% and 20.0% respectively. Our dental management protocol was proved to be effective in maintaining dental health and helpful in controlling osteoradionecrosis following head and neck radiotherapy. For a more effective outcome, we advocate that dental management should commence before the start of head and neck radiotherapy. (author)

  14. Dosimetric effects of the prone and supine positions on image guided localized prostate cancer radiotherapy

    International Nuclear Information System (INIS)

    Liu Bei; Lerma, Fritz A.; Patel, Shilpen; Amin, Pradip; Feng Yuanming; Yi, B.-Y.; Yu, Cedric

    2008-01-01

    Purpose: To compare target coverage and doses to rectum and bladder in IMRT of localized prostate cancer in the supine versus prone position, with the inclusion of image guidance. Materials and methods: Twenty patients with early stage localized prostate carcinoma who received external beam radiotherapy in the supine and prone positions underwent approximately 10 serial CT examinations in their respective treatment position in non-consecutive days, except for one patient who was treated prone but serially imaged supine. The prostate, bladder and rectum were contoured on all CT scans. A PTV was generated on the first scan of each patient's CT series by expanding the prostate with a 5 mm margin and an IMRT plan was created. The resultant IMRT plan was then applied to that patient's remaining serial CT scans by aligning the initial CT image set with the subsequent serial CT image sets using (1) skin marks, (2) bony anatomy and (3) center of mass of the prostate. The dosimetric results from these three alignments were compared between the supine and prone groups. To account for the uncertainties associated with prostate delineation and intra-fractional geometric changes, a fictional 'daily PTV' was generated by expanding the prostate with a 3 mm margin on each serial CT scan. Thus, a more realistic target coverage index, V95, was quantified as the fraction of the daily PTV receiving at least 95% of the prescription dose. Dose-volume measures of the organs at risk were also compared. The fraction of the daily PTV contained by the initial PTV after each alignment method was quantified on each patient's serial CT scan, and is defined as PTV overlap index. Results: As expected, alignment based on skin marks yielded unacceptable dose coverage for both groups of patients. Under bony alignment, the target coverage index, V95, was 97.3% and 93.6% for prone and supine patients (p < 0.0001), respectively. The mean PTV overlap indices were 90.7% and 84.7% for prone and supine

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-03-15

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

  16. Postimplantation Analysis Enables Improvement of Dose-Volume Histograms and Reduction of Toxicity for Permanent Seed Implantation

    International Nuclear Information System (INIS)

    Wust, Peter; Postrach, Johanna; Kahmann, Frank; Henkel, Thomas; Graf, Reinhold; Cho, Chie Hee; Budach, Volker; Boehmer, Dirk

    2008-01-01

    Purpose: To demonstrate how postimplantation analysis is useful for improving permanent seed implantation and reducing toxicity. Patients and Methods: We evaluated 197 questionnaires completed by patients after permanent seed implantation (monotherapy between 1999 and 2003). For 70% of these patients, a computed tomography was available to perform postimplantation analysis. The index doses and volumes of the dose-volume histograms (DVHs) were determined and categorized with respect to the date of implantation. Differences in symptom scores relative to pretherapeutic status were analyzed with regard to follow-up times and DVH descriptors. Acute and subacute toxicities in a control group of 117 patients from an earlier study (June 1999 to September 2001) by Wust et al. (2004) were compared with a matched subgroup from this study equaling 110 patients treated between October 2001 and August 2003. Results: Improved performance, identifying a characteristic time dependency of DVH parameters (after implantation) and toxicity scores, was demonstrated. Although coverage (volume covered by 100% of the prescription dose of the prostate) increased slightly, high-dose regions decreased with the growing experience of the users. Improvement in the DVH and a reduction of toxicities were found in the patient group implanted in the later period. A decline in symptoms with follow-up time counteracts this gain of experience and must be considered. Urinary and sexual discomfort was enhanced by dose heterogeneities (e.g., dose covering 10% of the prostate volume, volume covered by 200% of prescription dose). In contrast, rectal toxicities correlated with exposed rectal volumes, especially the rectal volume covered by 100% of the prescription dose. Conclusion: The typical side effects occurring after permanent seed implantation can be reduced by improving the dose distributions. An improvement in dose distributions and a reduction of toxicities were identified with elapsed time between

  17. SU-F-T-500: The Effectiveness of a Patient Specific Bolus Made by Using Three-Dimensional Printing Technique in Photon Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, K; Yuasa, Y [Department of Radiological Technology, Yamaguchi University Hospital (Japan); Shiinoki, T; Hanazawa, H; Shibuya, K [Department of Radiation Oncology, Graduate school of Medicine, Yamaguchi University (Japan)

    2016-06-15

    Purpose: A commercially available bolus (commercial-bolus) would not completely contact with the irregular shape of a patient’s skin. The purposes of this study were to customize a patient specific three-dimensional (3D) bolus using a 3D printer (3D-bolus) and to evaluate its clinical feasibility for photon radiotherapy. Methods: The 3D-bolus was designed using a treatment planning system (TPS) in DICOM-RT format. To print the 3D bolus, the file was converted into stereolithography format. To evaluate its physical characteristics, plans were created for water equivalent phantoms without the bolus, with the 3D-bolus printed in a flat form, and with the virtual bolus which supposed a commercial-bolus. These plans were compared with the percent depth dose (PDD) measured from the TPS. Furthermore, to evaluate its clinical feasibility, the treatment plans were created for RANDO phantoms without the bolus and with the 3D-bolus which was customized for contacting with the surface of the phantom. Both plans were compared with the dose volume histogram (DVH) of the target volume. Results: In the physical evaluation, dmax of the plan without the bolus, with the 3D-bolus, and with the virtual bolus were 2.2 cm, 1.6 cm, and 1.7 cm, respectively. In the evaluation of clinical feasibility, for the plan without the bolus, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 102.6 %, 1.6 %, 88.8 %, 57.2 %, and 69.3 %, respectively. By using the 3D-bolus, the prescription dose could be delivered to at least 90 % of the target volume, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 104.3 %, 91.6 %, 92.1 %, 91.7 %, and 98.0 %, respectively. The 3D-bolus has the potential to be useful for providing effective dose coverage in the buildup region. Conclusion: A 3D-bolus produced using 3D printing technique is comparable to a commercially available bolus.

  18. SU-F-T-500: The Effectiveness of a Patient Specific Bolus Made by Using Three-Dimensional Printing Technique in Photon Radiotherapy

    International Nuclear Information System (INIS)

    Fujimoto, K; Yuasa, Y; Shiinoki, T; Hanazawa, H; Shibuya, K

    2016-01-01

    Purpose: A commercially available bolus (commercial-bolus) would not completely contact with the irregular shape of a patient’s skin. The purposes of this study were to customize a patient specific three-dimensional (3D) bolus using a 3D printer (3D-bolus) and to evaluate its clinical feasibility for photon radiotherapy. Methods: The 3D-bolus was designed using a treatment planning system (TPS) in DICOM-RT format. To print the 3D bolus, the file was converted into stereolithography format. To evaluate its physical characteristics, plans were created for water equivalent phantoms without the bolus, with the 3D-bolus printed in a flat form, and with the virtual bolus which supposed a commercial-bolus. These plans were compared with the percent depth dose (PDD) measured from the TPS. Furthermore, to evaluate its clinical feasibility, the treatment plans were created for RANDO phantoms without the bolus and with the 3D-bolus which was customized for contacting with the surface of the phantom. Both plans were compared with the dose volume histogram (DVH) of the target volume. Results: In the physical evaluation, dmax of the plan without the bolus, with the 3D-bolus, and with the virtual bolus were 2.2 cm, 1.6 cm, and 1.7 cm, respectively. In the evaluation of clinical feasibility, for the plan without the bolus, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 102.6 %, 1.6 %, 88.8 %, 57.2 %, and 69.3 %, respectively. By using the 3D-bolus, the prescription dose could be delivered to at least 90 % of the target volume, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 104.3 %, 91.6 %, 92.1 %, 91.7 %, and 98.0 %, respectively. The 3D-bolus has the potential to be useful for providing effective dose coverage in the buildup region. Conclusion: A 3D-bolus produced using 3D printing technique is comparable to a commercially available bolus.

  19. Effectiveness of fractionated stereotactic radiotherapy for uveal melanoma

    International Nuclear Information System (INIS)

    Muller, Karin; Nowak, Peter; Pan, Connie de; Marijnissen, Johannes P.; Paridaens, Dion A.; Levendag, Peter; Luyten, Gre P.M.

    2005-01-01

    Purpose: To study the effectiveness and acute side effects of fractionated stereotactic radiation therapy (fSRT) for uveal melanoma. Methods and Materials: Between 1999 and 2003, 38 patients (21 male, 17 female) were included in a prospective, nonrandomized clinical trial (mean follow-up of 25 months). A total dose of 50 Gy was given in 5 consecutive days. A blinking light and a camera (to monitor the position of the diseased eye) were fixed to a noninvasive relocatable stereotactic frame. Primary end points were local control, best corrected visual acuity, and toxicity at 3, 6, 12, and 24 months, respectively. Results: After 3 months (38 patients), the local control was 100%; after 12 months (32 patients) and 24 months (15 patients), no recurrences were seen. The best corrected visual acuity declined from a mean of 0.21 at diagnosis to 0.06 2 years after therapy. The acute side effects after 3 months were as follows: conjunctival symptoms (10), loss of lashes or hair (6), visual symptoms (5), fatigue (5), dry eye (1), cataract (1), and pain (4). One eye was enucleated at 2 months after fSRT. Conclusions: Preliminary results demonstrate that fSRT is an effective and safe treatment modality for uveal melanoma with an excellent local control and mild acute side effects. The follow-up should be prolonged to study both long-term local control and late toxicity

  20. Tetrahydrocannabinol vs. Prochlorperazine: the effects of two antiemetics on patients undergoing radiotherapy

    International Nuclear Information System (INIS)

    Ungerleider, J.T.; Andrysiak, T.A.; Fiarbanks, L.A.; Tesler, A.S.; Parker, R.G.

    1984-01-01

    The authors tested the effectiveness of orally administred delta-9-tetrahydrocannabinol (THC) as compared to prochlorperazine for the alleviation of symptoms, such as vomiting and nausea, experienced by patients receiving radiotherapy. The test subjects rated the severity of their illness, as well as the extent of their subsequent moods, their level of concentration, their amount of physical activity, and their desire for social interaction. They chose the drug they preferred and recorded its side effects. The use of THC was slightly more beneficial than the use of prochlorperazine

  1. Influence of Routine MV CBCT Usage on Dose Distribution in Pelvic Radiotherapy

    International Nuclear Information System (INIS)

    Faj, D.; Kasabasic, M.; Ivkovic, A.; Tomas, I.; Jurkovic, S.

    2013-01-01

    The pelvic radiotherapy is a standard treatment for patients with cervical, uterine and rectal carcinomas. During radiation treatment open tabletop device or bellyboard is used to reduce the side effects of healthy surrounding tissue. Patients are continually adjusting to the bellyboard during the treatment which causes geometrical and dosage uncertainties and influences the results of the treatment. Therefore, to reduce these uncertainties, megavoltage cone-beam computed tomography (MV CBCT) system is used. The objective of this research was to evaluate the image acquisition dose delivered to patients from MV CBCT. MV CBCT imaging was simulated on 15 patients using 3D treatment planning software XiO (CMS Inc., St. Louis, MO). The influence of the routine MV CBCT usage on treatment plan was investigated by analyzing the changes in dose volume histograms, mean values and maximum doses in the planning volumes. Simulations have shown that daily usage of MV CBCT causes differences in the dose volume histograms. Moreover, for every patient mean value exceeded prescribed tolerance (±1% of the prescribed dose) and maximum value exceeded recommended maximum of 107% of the prescribed dose. The results have shown that MV CBCT dose to the patient should be a part of the RT plan.(author)

  2. Evidence for radiation-induced Bystander effects and relevance to radiotherapy and to radiation protection

    International Nuclear Information System (INIS)

    Georgieva, R.

    2006-01-01

    Full text: There are two major arms of radiation science in which Bystander effects (ByEff) could be of practical importance: radiotherapy and risk assessment. Basic biological principles, including dose-response relationships that have become dogma in the context of targeted effects of IR must now be reconsidered. The direct effects of radiation and the bystander components had to be reinvestigated to show the difference between them. It may be necessary to introduce a factor for ByEff's when calculating dose to both normal tissues and tumor. Presumably the relative effects on normal or tumor tissues could be different and that difference may not be always predictable. In relation to radiation protection, the existence of RIByEff's raises important questions for the way radiation dose is measured and modeled. The biological effect of exposure to low-doses radiation is likely to vary between individuals and between organs in one the same individual. Further studies on non-targeted effects should contribute to the establishment of adequate environmental and occupational radiation protection standards. This lecture looks at the history, the current data and controversies that are now beginning to resolve the questions concerning the mechanisms underlying the induction and transmission of ByEff. Especially, effects on radiotherapy and radiation protection are discussed

  3. Chemotherapy disruption of efficient radiotherapy

    International Nuclear Information System (INIS)

    Nervi, C.; Friedman, M.

    1974-01-01

    Studies on the use of chemotherapy in combination with radiotherapy are reviewed. Some topics discussed are: indications for the use of combined chemotherapy and radiotherapy; improvement of the therapeutic ratio following the use of methotrexate; advantages of preirradiation and postirradiation chemotherapy; side effects following simultaneous chemotherapy and radiotherapy; and effects of chemotherapy on cure rate of radiosensitive and radioresistant tumors. (U.S.)

  4. Combined effects of radiotherapy and chemotherapy normal tissue, 1

    International Nuclear Information System (INIS)

    Watanabe, Noriaki

    1983-01-01

    The combined effects of radiation and drugs on the fine vasculature of mouse liver were investigated by microangiography. The fine vasculature of the liver showed dilatations one day after 1000 rad of irradiation to the liver. The fine vasculature of the liver showed marked dilatations and slight extravasations one day after 1000 rad of irradiation to the whole body. The fine vasculature of the liver showed dilatations and partial narrowings after the administration of BLM, 2mg/kg/day ip for 5 days. The combined effects of BLM and radiation was greater than that with radiation alone. The fine vasculature of the liver showed marked dilatations and slight extravasation after the administration of BLM, 2mg/kg/day ip for 5 days and MMC 2mg/kg ip on day 6. This findings is about the same as that after the administration of BLM and 1000 rad of irradiation. The administration of urokinase did not diminish the effects of radiation on the fine vasculature of the liver. The administration of YM-08310 diminished the effects of irradiation on the fine vasculature of the liver. (author)

  5. Dose-volume complication analysis for visual pathway structures of patients with advanced paranasal sinus tumors

    International Nuclear Information System (INIS)

    Martel, Mary Kaye; Sandler, Howard M.; Cornblath, Wayne T.; Marsh, Lon H.; Hazuka, Mark B.; Roa, Wilson H.; Fraass, Benedict A.; Lichter, Allen S.

    1997-01-01

    Purpose: The purpose of the present work was to relate dose and volume information to complication data for visual pathway structures in patients with advanced paranasal sinus tumors. Methods and Materials: Three-dimensional (3D) dose distributions for chiasm, optic nerve, and retina were calculated and analyzed for 20 patients with advanced paranasal sinus malignant tumors. 3D treatment planning with beam's eye view capability was used to design beam and block arrangements, striving to spare the contralateral orbit (to lessen the chance of unilateral blindness) and frequently the ipsilateral orbit (to help prevent bilateral blindness). Point doses, dose-volume histogram analysis, and normal tissue complication probability (NTCP) calculations were performed. Published tolerance doses that indicate significant risk of complications were used as guidelines for analysis of the 3D dose distributions. Results: Point doses, percent volume exceeding a specified published tolerance dose, and NTCP calculations are given in detail for patients with complications versus patients without complications. Two optic nerves receiving maximum doses below the published tolerance dose sustained damage (mild vision loss). Three patients (of 13) without optic nerve sparing and/or chiasm sparing had moderate or severe vision loss. Complication data, including individual patient analysis to estimate overall risk for loss of vision, are given. Conclusion: 3D treatment planning techniques were used successfully to provide bilateral sparing of the globe for most patients. It was more difficult to spare the optic nerves, especially on the ipsilateral side, when prescription dose exceeded the normal tissue tolerance doses. NTCP calculations may be useful in assessing complication risk better than point dose tolerance criteria for the chiasm, optic nerve, and retina. It is important to assess the overall risk of blindness for the patient in addition to the risk for individual visual pathway

  6. Dose volume assessment of high dose rate 192IR endobronchial implants

    International Nuclear Information System (INIS)

    Cheng, B. Saw; Korb, Leroy J.; Pawlicki, Todd; Wu, Andrew

    1996-01-01

    Purpose: To study the dose distributions of high dose rate (HDR) endobronchial implants using the dose nonuniformity ratio (DNR) and three volumetric irradiation indices. Methods and Materials: Multiple implants were configured by allowing a single HDR 192 Ir source to step through a length of 6 cm along an endobronchial catheter. Dwell times were computed to deliver a dose of 5 Gy to points 1 cm away from the catheter axis. Five sets of source configurations, each with different dwell position spacings from 0.5 to 3.0 cm, were evaluated. Three-dimensional (3D) dose distributions were then generated for each source configuration. Differential and cumulative dose-volume curves were generated to quantify the degree of target volume coverage, dose nonuniformity within the target volume, and irradiation of tissues outside the target volume. Evaluation of the implants were made using the DNR and three volumetric irradiation indices. Results: The observed isodose distributions were not able to satisfy all the dose constraints. The ability to optimally satisfy the dose constraints depended on the choice of dwell position spacing and the specification of the dose constraint points. The DNR and irradiation indices suggest that small dwell position spacing does not result in a more homogeneous dose distribution for the implant. This study supports the existence of a relationship between the dwell position spacing and the distance from the catheter axis to the reference dose or dose constraint points. Better dose homogeneity for an implant can be obtained if the spacing of the dwell positions are about twice the distance from the catheter axis to the reference dose or dose constraint points

  7. Long-term effects on carotid intima-media thickness after radiotherapy in patients with nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Huang, Tai-Lin; Huang, Chi-Ren; Tsai, Nai-Wen; Kung, Chia-Te; Wang, Hung-Chen; Lin, Wei-Che; Cheng, Ben-Chung; Su, Yu-Jih; Chang, Ya-Ting; Chang, Chuang-Rung; Tan, Teng-Yeow; Hsu, Hsuan-Chih; Lu, Cheng-Hsien; Chen, Hui-Chun; Lin, Hsin-Ching; Chien, Chih-Yen; Fang, Fu-Min; Huang, Chih-Cheng; Chang, Hsueh-Wen; Chang, Wen-Neng

    2013-01-01

    Vascular abnormalities are the predominant histologic changes associated with radiation in nasopharyngeal carcinoma (NPC). This study examined if the duration after radiotherapy correlates with the progression of carotid intima-media thickness (IMT) and investigated its relationship with inflammatory markers. One hundred and five NPC patients post-radiotherapy for more than one year and 25 healthy control subjects were examined by B-mode ultrasound for IMT measurement at the far wall of the common carotid artery (CCA). Surrogate markers including lipid profile, HbA1c, and high sensitive C-reactive protein (hs-CRP) were assessed. The IMT of CCA was significantly increased in NPC patients and carotid plaque was detected in 38 NPC patients (38/105, 36.2%). Significant risk factors for carotid plaques included age, duration after radiotherapy, and HbA1c levels. Age, duration after radiotherapy, hs-CRP, HbA1c, and platelet count positively correlated with IMT. The cut-off value of age and duration after radiotherapy for the presence of plaque was 52.5 years and 42.5 months, respectively. In NPC subjects, multiple linear regression analysis revealed that age, gender, duration after radiotherapy and platelet counts were independently associated with CCA IMT. After adjustments for age, gender and platelet counts, IMT increased in a linear manner with duration after radiotherapy. Radiation-induced vasculopathy is a dynamic and progressive process due to late radiation effects. Extra-cranial color-coded duplex sonography can be part of routine follow-up in NPC patients aged ≥50 years at 40 months post-radiotherapy

  8. Dosimetric Effects Of Different Treatment Tables During Radiotherapy

    International Nuclear Information System (INIS)

    Murkovic, M.; Grego, T.; Bibic, J.

    2015-01-01

    The aim of our study was to measure the effect of mega-voltage photon beam attenuation when treating patients through carbon fibre treatment table with and without the carbon laminate base plate on it. We also examined the ability of XiO treatment planning system in modelling this effect. Direct attenuation measurements were made for two treatment tables, Siemens TxT 550 treatment table with TT-A table top and Elekta Precise table with iBEAM evo table top. On both treatment tables we used Orfit Base Plate (32301). Measurements were taken for two photon energies (6 MV and 18 MV), at two different field sizes (5 x 5 cm 2 and 10 x 10 cm 2 ) and different gantry angles in 50 intervals using stationary water phantom and Farmer type ionization chamber. These values were compared to values calculated in XiO. In order to account for the effect of table and base plate during treatment planning in XiO, customized table and base plate templates were develop in Focal planning system. To construct these customized templates, table and base plate contours as well as respective relative electron density's to water were obtained on CT scanner. The largest attenuation effect was seen for oblique treatment angles using low energy and small field sizes, 6.6 percent for the Elekta table top and 8.4 percent for Siemens table top. In this paper we show that customized table and base plate templates introduced in the patient treatment plan can accurately model the attenuation due to their presence to within 0.3 percent. Since dose modifications due to such carbon fiber accessories can be significant, it can be concluded that introduction of customized table and base plate templates into TPS brings an important improvement to patient treatment planning, and should be included in dose calculations whenever possible. (author).

  9. SU-F-T-245: The Investigation of Failure Mode and Effects Analysis and PDCA for the Radiotherapy Risk Reduction

    International Nuclear Information System (INIS)

    Xie, J; Wang, J; P, J; Chen, J; Hu, W

    2016-01-01

    Purpose: To optimize the clinical processes of radiotherapy and to reduce the radiotherapy risks by implementing the powerful risk management tools of failure mode and effects analysis(FMEA) and PDCA(plan-do-check-act). Methods: A multidiciplinary QA(Quality Assurance) team from our department consisting of oncologists, physicists, dosimetrists, therapists and administrator was established and an entire workflow QA process management using FMEA and PDCA tools was implemented for the whole treatment process. After the primary process tree was created, the failure modes and Risk priority numbers(RPNs) were determined by each member, and then the RPNs were averaged after team discussion. Results: 3 of 9 failure modes with RPN above 100 in the practice were identified in the first PDCA cycle, which were further analyzed to investigate the RPNs: including of patient registration error, prescription error and treating wrong patient. New process controls reduced the occurrence, or detectability scores from the top 3 failure modes. Two important corrective actions reduced the highest RPNs from 300 to 50, and the error rate of radiotherapy decreased remarkably. Conclusion: FMEA and PDCA are helpful in identifying potential problems in the radiotherapy process, which was proven to improve the safety, quality and efficiency of radiation therapy in our department. The implementation of the FMEA approach may improve the understanding of the overall process of radiotherapy while may identify potential flaws in the whole process. Further more, repeating the PDCA cycle can bring us closer to the goal: higher safety and accuracy radiotherapy.

  10. SU-F-T-245: The Investigation of Failure Mode and Effects Analysis and PDCA for the Radiotherapy Risk Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Xie, J; Wang, J; P, J; Chen, J; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To optimize the clinical processes of radiotherapy and to reduce the radiotherapy risks by implementing the powerful risk management tools of failure mode and effects analysis(FMEA) and PDCA(plan-do-check-act). Methods: A multidiciplinary QA(Quality Assurance) team from our department consisting of oncologists, physicists, dosimetrists, therapists and administrator was established and an entire workflow QA process management using FMEA and PDCA tools was implemented for the whole treatment process. After the primary process tree was created, the failure modes and Risk priority numbers(RPNs) were determined by each member, and then the RPNs were averaged after team discussion. Results: 3 of 9 failure modes with RPN above 100 in the practice were identified in the first PDCA cycle, which were further analyzed to investigate the RPNs: including of patient registration error, prescription error and treating wrong patient. New process controls reduced the occurrence, or detectability scores from the top 3 failure modes. Two important corrective actions reduced the highest RPNs from 300 to 50, and the error rate of radiotherapy decreased remarkably. Conclusion: FMEA and PDCA are helpful in identifying potential problems in the radiotherapy process, which was proven to improve the safety, quality and efficiency of radiation therapy in our department. The implementation of the FMEA approach may improve the understanding of the overall process of radiotherapy while may identify potential flaws in the whole process. Further more, repeating the PDCA cycle can bring us closer to the goal: higher safety and accuracy radiotherapy.

  11. Late normal tissue effects in the arm and shoulder following lymphatic radiotherapy: Results from the UK START (Standardisation of Breast Radiotherapy) trials.

    Science.gov (United States)

    Haviland, Joanne S; Mannino, Mariella; Griffin, Clare; Porta, Nuria; Sydenham, Mark; Bliss, Judith M; Yarnold, John R

    2018-01-01

    Adjuvant lymphatic radiotherapy (LNRT) is recommended for selected axillary node positive women with early breast cancer. We investigated whether hypofractionated LNRT is safe combined with similarly-hypofractionated breast/chest wall radiotherapy (RT). The Standardisation of Breast Radiotherapy (START) pilot, A and B trials randomised women with early breast cancer to schedules of 2.67-3.3 Gy versus 2.0 Gy fractions (control). RT adverse effects were assessed by patients using the EORTC QLQ-BR23 and protocol-specific questions, and by physicians. Rates of arm/shoulder effects were compared between schedules for patients given LNRT. 864/5861 (14.7%) patients received LNRT (385 START-pilot, 318 START-A, 161 START-B). Prevalences of moderate/marked arm/shoulder effects were low up to 10 years. There were no significant differences between the hypofractionated and control groups for patient- and physician-assessed symptoms in START-A or START-B. In START-pilot, adverse effect rates were higher after 13 fractions of 3.3 Gy, consistent with effects reported in the breast/chest wall (significant for shoulder stiffness, HR 3.07, 95%CI 1.62-5.83, p = 0.001). The START trial results suggest that appropriately-dosed hypofractionated LNRT is safe in the long-term, according to patient and physician-assessed arm and shoulder symptoms. These findings are consistent with those reported after the same schedules delivered to the breast/chest wall. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  12. Radiotherapy high energy surface dose measurements: effects of chamber polarity

    International Nuclear Information System (INIS)

    Cheung, T.; Yu, P.K.N.; Butson, M.J.; Cancer Services, Wollongong, NSW

    2004-01-01

    Full text: The effects of chamber polarity have been investigated for the measurement of 6MV and 18MV x-ray surface dose using a parallel plate ionization chamber. Results have shown that a significant difference in measured ionization is recorded between to polarities at 6MV and 18MV at the phantom surface. A polarity ratio ranging from 1 062 to 1 005 is seen for 6MV x-rays at the phantom surface for field sizes 5cm x 5cm to 40cm x 40cm when comparing positive to negative polarity. These ratios range from 1.024 to 1.004 for 18MV x-rays with the same field sizes. When these charge reading are compared to the D max readings of the same polarity it is found that these polarity effects are minimal for the calculation of percentage dose results with variations being less than 1% of maximum. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

  13. Late effects of external radiotherapy on the thyroid gland; Effets tardifs de la radiotherapie externe sur la glande thyroide

    Energy Technology Data Exchange (ETDEWEB)

    Monnier, A. [Centre Hospitalier general A-Boulloche, 25 - Montbeliard (France)

    1997-12-01

    The thyroid is the purest endocrine gland in the body and is likely to produce clinically significant abnormalities after external radiotherapy. Functional clinical modifications after direct irradiation exceeding 30 Gy are essentially related to hypothyroidism which may be clinically overt or subclinical with normal serum free thyroxine levels and high thyrotropin concentrations; the risk of hyperthyroidism, silent thyroiditis and Hashimoto`s disease is also increased. secondary hypothyroidism related to irradiation of the hypothalamus and the pituitary gland may arise with doses over 40-50 Gy following treatment for brain and nasopharyngeal tumors - Morphological glandular modifications induced by radiotherapy are responsible for the appearance of benign adenomas, more rarely cystic degenerations and specially well differentiated papillary or follicular carcinomas among children and adults. After irradiation during childhood for benign or malignant tumors, thyroid cancers are more frequent, higher for younger children, and the relative excess risk is increased from 15.6-to 53-fold; tumors can belatedly occur, more than 35 years after initial therapy. Thereby, in order to limit excess morbidity, it is evident that long term supervision with careful clinical and biological evaluations is necessary for patients who previously received neck, upper mediastinum and pituitary radiation therapy. (author)

  14. Immediate side effects of stereotactic radiotherapy and radiosurgery

    International Nuclear Information System (INIS)

    Werner-Wasik, Maria; Rudoler, Shari; Preston, Peter E.; Hauck, Walter W.; Downes, Beverly M.; Leeper, Dennis; Andrews, David; Corn, Benjamin W.; Curran, Walter J.

    1999-01-01

    Purpose: Despite increased utilization of fractionated stereotactic radiation therapy (SRT) or stereotactic radiosurgery (SRS), the incidence and nature of immediate side effects (ISE) associated with these treatment techniques are not well defined. We report immediate side effects from a series of 78 patients. Materials and Methods: Intracranial lesions in 78 adult patients were treated with SRT or SRS, using a dedicated linear accelerator. Those lesions included 13 gliomas, 2 ependymomas, 19 metastatic tumors, 15 meningiomas, 12 acoustic neuromas, 4 pituitary adenomas, 1 optic neuroma, 1 chondrosarcoma, and 11 arteriovenous malformations (AVM). SRT was used in 51 and SRS in 27 patients. Mean target volume was 9.0 cc. Eleven patients received prior external-beam radiation therapy within 2 months before SRT/SRS. Any side effects occurring during and up to 2 weeks after the course of radiation were defined as ISE and were graded as mild, moderate, or severe. The incidence of ISE and the significance of their association with several treatment and pretreatment variables were analyzed. Results: Overall, 28 (35%) of 78 patients experienced one or more ISE. Most of the ISE (87%) were mild, and consisted of nausea (in 5), dizziness/vertigo (in 5), seizures (in 6), and new persistent headaches (in 17). Two episodes of worsening neurological deficit and 2 of orbital pain were graded as moderate. Two patients experienced severe ISE, requiring hospitalization (1 seizure and 1 worsening neurological deficit). ISE in 6 cases prompted computerized tomography of the brain, which revealed increased perilesional edema in 3 cases. The incidence of ISE by diagnosis was as follows: 46% (6 of 13) for gliomas, 50% (6 of 12) for acoustic neuromas, 36% (4 of 11) for AVM, 33% (5 of 15) for meningiomas, and 21% (4 of 19) for metastases. A higher incidence of dizziness/vertigo (4 of 12 = 33%) was seen among acoustic neuroma patients than among other patients (p < 0.01). There was no

  15. Anti-emetic effect of granisetron in patients undergoing cranial and craniospinal radiotherapy

    International Nuclear Information System (INIS)

    Yamasaki, Fumiyuki; Watanabe, Yosuke; Nosaka, Ryo

    2014-01-01

    Approximately 30-59% of patients undergoing cranial or craniospinal radiotherapy experience nausea and/or vomiting. Here, we evaluated the effectiveness of granisetron for controlling emesis in patients treated with cranial or craniospinal radiotherapy. Between December 2011 and January 2013, 34 patients (19 males, 15 females; age range, 3-80 years) received cranial or craniospinal radiotherapy at our department. All but one male patient, who developed meningitis during the irradiation period were enrolled in this retrospective study. Patients who experienced irradiation-induced vomiting (grade 1) or nausea (grade 2) were treated with granisetron as a rescue anti-emetic. Episodes were graded as no vomiting, no nausea, no anti-emetic; no vomiting, nausea, no anti-emetic; no vomiting, nausea with anti-emetic; and vomiting. Of the 9 patients who underwent whole-brain or whole neural-axis irradiation, 5 (55.6%) experienced grade 2 nausea or vomiting. Two of 6 patients (33.3%) treated with whole ventricle irradiation experienced grade 2 nausea or vomiting. Three of 18 patients (16.7%) who underwent local-field irradiation experienced grade 2 nausea or vomiting. Patients who underwent wide-field irradiation experienced nausea, vomiting, and anorexia (p<0.05). Complete response (no vomiting, no additional rescue anti-emetic, and no nausea) was observed in 5 of 9 patients treated with granisetron. Four of 9 patients (44.4%) treated with granisetron experienced constipation (grade 1 or 2); its administration had no major adverse effects in our study population. Rescue therapy with granisetron is safe and effective to treat nausea and vomiting in patients subjected to cranial or craniospinal irradiation. (author)

  16. [Anti-emetic effect of granisetron in patients undergoing cranial and craniospinal radiotherapy].

    Science.gov (United States)

    Yamasaki, Fumiyuki; Watanabe, Yosuke; Nosaka, Ryo; Kenjo, Masahiro; Nakamura, Kazuhiro; Takayasu, Takeshi; Saito, Taiichi; Tominaga, Atsushi; Sugiyama, Kazuhiko; Kurisu, Kaoru

    2014-01-01

    Approximately 30-59% of patients undergoing cranial or craniospinal radiotherapy experience nausea and/or vomiting. Here, we evaluated the effectiveness of granisetron for controlling emesis in patients treated with cranial or craniospinal radiotherapy. Between December 2011 and January 2013, 34 patients(19 males, 15 females;age range, 3-80 years)received cranial or craniospinal radiotherapy at our department. All but one male patient, who developed meningitis during the irradiation period were enrolled in this retrospective study. Patients who experienced irradiation-induced vomiting(grade 1)or nausea(grade 2)were treated with granisetron as a rescue anti-emetic. Episodes were graded as(1)no vomiting, no nausea, no anti-emetic;(2)no vomiting, nausea, no anti-emetic;(3)no vomiting, nausea with anti-emetic;and(4)vomiting. Of the 9 patients who underwent whole-brain or whole neural-axis irradiation, 5(55.6%)experienced grade 2 nausea or vomiting. Two of 6 patients(33.3%)treated with whole ventricle irradiation experienced grade 2 nausea or vomiting. Three of 18 patients(16.7%)who underwent local-field irradiation experienced grade 2 nausea or vomiting. Patients who underwent wide-field irradiation experienced nausea, vomiting, and anorexia(pgranisetron. Four of 9 patients(44.4%)treated with granisetron experienced constipation(grade 1 or 2);its administration had no major adverse effects in our study population. Rescue therapy with granisetron is safe and effective to treat nausea and vomiting in patients subjected to cranial or craniospinal irradiation.

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

    International Nuclear Information System (INIS)

    Rao, B.S.

    2013-01-01

    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 32 P, 86 Rb, 144m In 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)

  18. The effect of interruptions and prolonged treatment time in radiotherapy for nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Kwong, Dora L.W.; Sham, Jonathan S.T.; Chua, Daniel T.T.; Choy, Damon T.K.; Au, Gordon K.H.; Wu, P.M.

    1997-01-01

    Purpose: The effect of interruptions and prolonged overall treatment time in radiotherapy for nasopharyngeal carcinoma and the significance of timing of interruption was investigated. Methods and Materials: Treatment records of 229 patients treated with continuous course (CC) and 567 patients treated with split course (SC) radiotherapy for nonmetastatic NPC were reviewed. Overall treatment time without inclusion of time for boost was calculated. Treatment that extended 1 week beyond scheduled time was considered prolonged. Outcome in patients who completed treatment 'per schedule' were compared with those who had 'prolonged' treatment. Because of known patient selection bias between CC and SC, patients on the two schedules were analyzed separately. Multivariate analysis was performed for patients on SC. Total number of days of interruption, age, sex, T and N stage, and the use of boost were tested for the whole SC group. Analysis on the effect of timing of interruption was performed in a subgroup of 223 patients on SC who had a single unplanned interruption. Timing of interruption, either before or after the fourth week for the unplanned interruption, was tested in addition to the other variables in multivariate analysis for this subgroup of SC. Results: Twenty-seven (11.8%) patients on CC and 96 (16.9%) patients on SC had prolonged treatment. Patients on SC who had prolonged treatment had significantly poorer loco-regional control rate and disease free survival when compared with those who completed radiotherapy per schedule (p = 0.0063 and 0.001, respectively, with adjustment for stage). For CC, the effect of prolonged treatment on outcome was not significant. The small number of events for patients on CC probably account for the insignificant finding. The number of days of interruption was confirmed as prognostic factor, independent of T and N stages, for loco-regional control and disease-free survival in multivariate analysis for SC. The hazard rate for loco

  19. Histopathological effects of intraoperative radiotherapy on pancreas and adjacent tissues: a postmortem analysis

    International Nuclear Information System (INIS)

    Hoekstra, H.J.; Restrepo, C.; Kinsella, T.J.; Sindelar, W.F.

    1988-01-01

    Intraoperative radiotherapy (IORT) has been utilized in the treatment of resectable and unresectable pancreatic carcinoma at the National Cancer Institute. Detailed autopsy analyses of the radiation effects on the pancreas and adjacent tissues were performed on 13 patients dying at various times following therapy. IORT can induce a progressive retroperitoneal fibrosis and fibrosis of the porta hepatis in patients with resectable pancreatic carcinoma. In unresectable pancreatic carcinoma, the major expression of intraoperative irradiation with external beam irradiation is a progressive fibrosis of the pancreas with vascular sclerosis, nerve degeneration, atrophy of acinar cells, and atypical changes in the ducts of the pancreas, as well as degenerative changes of the pancreatic tumor

  20. Effects from postoperative radiotherapy of parasellar ademonas of the pituitary gland

    International Nuclear Information System (INIS)

    Buchfelder, M.

    1984-01-01

    In this study, the effects from postoperative radiotherapy of parasellar or suprasellar adenomas of the pituitary were analysed to provide more detailed information about the value of radiation treatment, when used as a secondary measure after surgery or even in the primary treatment of pituitary adenomas. The analysis was based on 75 patients showing parasellar or suprasellar tumours of the pituitary. Radiation was in most cases preceded by surgery and carried out in the Radiological Department of Munich's University Hospital after the year 1975, when computed tomography had been made available to the Neurosurgical Department of this clinic. (orig./MG) [de

  1. Immediate side effects of stereotactic radiotherapy and radiosurgery

    International Nuclear Information System (INIS)

    Werner-Wasik, Maria; Rudoler, Shari; Preston, Peter E.; Downes, Beverly M.; Andrews, David; Corn, Benjamin W.; Rosenstock, Jeffrey; Curran, Walter J.

    1996-01-01

    Purpose/Objective: Despite increased utilization of fractionated stereotactic radiation therapy (SRT) or stereotactic radiosurgery (SRS), the incidence and nature of immediate side effects (ISE) associated with these treatment techniques is not well defined. Materials and Methods: Intracranial lesions in 78 adult patients were treated with SRT or SRS, using a dedicated linear accelerator. They comprised 13 gliomas, 2 ependymomas, 19 metastatic tumors, 15 meningiomas, 12 acoustic neuromas, 4 pituitary adenomas, 1 optic neuroma, 1 chondrosarcoma and 11 arteriovenous malformations (AVM). SRT was used in 51 and SRS in 27 patients. Mean target volume was 9.0 cc. Eleven patients received prior external beam radiation therapy within 2 months before SRT/SRS. Any side effects occurring during and up to two weeks after radiation course were defined as ISE and were graded as mild, moderate or severe. The incidence of ISE and the significance of their association with several pretreatment variables were analyzed. Results: Overall, (28(78)) (35%) patients experienced one or more ISE. Most of ISE (87%) were mild and consisted of nausea (5), dizziness/vertigo (5), seizures (7) and new persistent headaches (17). Two episodes of worsening neurological deficit and 2 of orbital pain were graded as moderate. Two patients experienced severe ISE, requiring hospitalization (1 seizure and 1 worsening neurological deficit). ISE in 5 cases prompted computerized tomography of the brain which revealed increased perilesional edema in 3 cases. The incidence of ISE by diagnosis was as follows: 46% ((6(13))) for gliomas, 50% ((6(12))) for acoustic neuromas, 36% ((4(11))) for AVM, 33% ((5(15))) for meningiomas and 21% ((4(19))) for metastases. Increasing dose to the margin and increasing maximum dose were associated with a higher incidence of ISE (p=0.02 and 0.005, respectively). Prior recent conventional external beam radiation therapy, target volume, number of isocenters, collimator size, dose

  2. Assessment of factors connected with radiotherapy influencing the cosmetic effect in breast conserving therapy

    International Nuclear Information System (INIS)

    Blaszczyk, P.; Roszkowski, K.; Blaszczyk, E.; Kowalewski, J.

    2009-01-01

    Aim: To compare cosmetic results of different radiotherapy schedules used in the treatment of breast cancer after breast radiotherapy and to identify factors affecting cosmetic outcomes. Material and methods: Ninety-four patients irradiated. Median follow-up of 29 months (range 18-154 mo.). Patients were treated with standard fractionation 45-50 Gy/20-25 fx/4-5 weeks. Boost up to 10 Gy. Late effects were evaluated using the LENT-SOMA scoring scale. The cosmetic results were assessed on a four-point scale and presence of concomitant chemotherapy. Results: LENT-SOMA grade 3 toxicity was observed only in 8 (8,5%) patients. The factor associated with hyperpigmentation is large breast size. The significant risk factors for teleangiectasia are high dose and use photon energy 1,33 MeV beam. Factors found to impact significantly cosmetics adversely fibrosis was large breast size. Breast fibrosis were more frequent observed in woman after whole dose 50 Gy. There were no differences in breast skin thick between analysed factors. Conclusions: After irradiating large breasts more often than one observes the fibrosis of the breast in the case of small and average breasts and discolour of the skin. Irradiating photons from the cobalt source in the comparison with photons about higher energy at women with large breasts, there is the reason more frequent occurrence of the skin angioma. For the final cosmetic effect of radiotherapy in saving treatment, they do not have the impact: tumor size, boost method, chemical treatment, patients age. (authors)

  3. The Dose-Volume Relationship of Small Bowel Irradiation and Acute Grade 3 Diarrhea During Chemoradiotherapy for Rectal Cancer

    International Nuclear Information System (INIS)

    Robertson, John M.; Lockman, David; Yan Di; Wallace, Michelle

    2008-01-01

    Purpose: Previous work has found a highly significant relationship between the irradiated small-bowel volume and development of Grade 3 small-bowel toxicity in patients with rectal cancer. This study tested the previously defined parameters in a much larger group of patients. Methods and Materials: A total of 96 consecutive patients receiving pelvic radiation therapy for rectal cancer had treatment planning computed tomographic scans with small-bowel contrast that allowed the small bowel to be outlined with calculation of a small-bowel dose-volume histogram for the initial intended pelvic treatment to 45 Gy. Patients with at least one parameter above the previously determined dose-volume parameters were considered high risk, whereas those with all parameters below these levels were low risk. The grade of diarrhea and presence of liquid stool was determined prospectively. Results: There was a highly significant association with small-bowel dose-volume and Grade 3 diarrhea (p ≤ 0.008). The high-risk and low-risk parameters were predictive with Grade 3 diarrhea in 16 of 51 high-risk patients and in 4 of 45 low-risk patients (p = 0.01). Patients who had undergone irradiation preoperatively had a lower incidence of Grade 3 diarrhea than those treated postoperatively (18% vs. 28%; p = 0.31); however, the predictive ability of the high-risk/low-risk parameters was better for preoperatively (p = 0.03) than for postoperatively treated patients (p = 0.15). Revised risk parameters were derived that improved the overall predictive ability (p = 0.004). Conclusions: The highly significant dose-volume relationship and validity of the high-risk and low-risk parameters were confirmed in a large group of patients. The risk parameters provided better modeling for the preoperative patients than for the postoperative patients

  4. Relationships Between Rectal Wall Dose-Volume Constraints and Radiobiologic Indices of Toxicity for Patients With Prostate Cancer

    International Nuclear Information System (INIS)

    Marzi, Simona; Arcangeli, Giorgio; Saracino, Bianca; Petrongari, Maria G.; Bruzzaniti, Vicente; Iaccarino, Giuseppe; Landoni, Valeria; Soriani, Antonella; Benassi, Marcello

    2007-01-01

    Purpose: The purpose of this article was to investigate how exceeding specified rectal wall dose-volume constraints impacts on the risk of late rectal bleeding by using radiobiologic calculations. Methods and Materials: Dose-volume histograms (DVH) of the rectal wall of 250 patients with prostate cancer were analyzed. All patients were treated by three-dimensional conformal radiation therapy, receiving mean target doses of 80 Gy. To study the main features of the patient population, the average and the standard deviation of the distribution of DVHs were generated. The mean dose , generalized equivalent uniform dose formulation (gEUD), modified equivalent uniform dose formulation (mEUD) 0 , and normal tissue complication probability (NTCP) distributions were also produced. The DVHs set was then binned into eight classes on the basis of the exceeding or the fulfilling of three dose-volume constraints: V 40 = 60%, V 50 = 50%, and V 70 = 25%. Comparisons were made between them by , gEUD, mEUD 0 , and NTCP. Results: The radiobiologic calculations suggest that late rectal toxicity is mostly influenced by V 70 . The gEUD and mEUD 0 are risk factors of toxicity always concordant with NTCP, inside each DVH class. The mean dose, although a reliable index, may be misleading in critical situations. Conclusions: Both in three-dimensional conformal radiation therapy and particularly in intensity-modulated radiation therapy, it should be known what the relative importance of each specified dose-volume constraint is for each organ at risk. This requires a greater awareness of radiobiologic properties of tissues and radiobiologic indices may help to gradually become aware of this issue

  5. No damaging effect of chemotherapy in addition to radiotherapy on the thyroid axis in young adult survivors of childhood cancer

    NARCIS (Netherlands)

    van Santen, Hanneke M.; Vulsma, Thomas; Dijkgraaf, Marcel G.; Blumer, Regje M. E.; Heinen, Richard; Jaspers, Monique W. M.; Geenen, Maud M.; Offringa, Martin O.; de Vijlder, Jan J. M.; van den Bos, Cor

    2003-01-01

    Late effects of treatment for childhood cancer on the thyroid axis are ascribed predominantly to radiotherapy. Whether chemotherapy has an additional detrimental effect is still unclear. Our aim was to evaluate this effect in young adult survivors of a broad spectrum of childhood cancers. The

  6. To understand radiotherapy

    International Nuclear Information System (INIS)

    2009-01-01

    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

  7. Osteopontin and splice variant expression level in human malignant glioma: Radiobiologic effects and prognosis after radiotherapy

    International Nuclear Information System (INIS)

    Güttler, Antje; Giebler, Maria; Cuno, Peter; Wichmann, Henri; Keßler, Jacqueline; Ostheimer, Christian; Söling, Ariane; Strauss, Christian; Illert, Jörg; Kappler, Matthias; Vordermark, Dirk; Bache, Matthias

    2013-01-01

    Background and purpose: We investigated the role of the hypoxia-associated secreted glycoprotein osteopontin (OPN) in the response of malignant glioma to radiotherapy by characterizing OPN and its splice variants in vitro and in patient material. Material and methods: The effect of siRNA knockdown of OPN splice variants on cellular and radiobiologic behavior was analyzed in U251MG cells using OpnS siRNA (inhibition of all OPN splice variants) and OpnAC siRNA (knockdown only of OPNa and OPNc). OPN and splice variant mRNA levels were quantified in archival material of 41 glioblastoma tumor samples. Plasma OPN was prospectively measured in 33 malignant glioma patients. Results: Inhibition of OPNa and OPNc (OpnAC) reduced clonogenic survival in U251MG cells but did not affect proliferation, migration or apoptosis. Knockdown of all OPN splice variants (OpnS) resulted in an even stronger inhibition of clonogenic survival, while cell proliferation and migration were reduced and rate of apoptosis was increased. Additional irradiation had additive effects with both siRNAs. Plasma OPN increased continuously in malignant glioma patients and was associated with poor survival. Conclusions: OPNb is partially able to compensate the effects of OPNa and OPNc knockdown in U251MG cells. High OPN plasma levels at the end of radiotherapy are associated with poor survival

  8. Effects of cancer, radiotherapy and cytotoxic drugs on intestinal structure and function

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M T; Spector, M H; Ladman, A J [New Mexico Univ., Albuquerque (USA)

    1979-09-01

    Intestinal malabsorption and the structural changes in the small intestine in relation to cancer, radiotherapy and cytotoxic drugs are reviewed. Primary intestinal malignancies are often associated with malabsorption; further studies have shown that tumours outside the gastrointestinal tract may also be accompanied by changes in intestinal structure resulting in malabsorption. Abdominal radiotherapy of cancer patients has been shown to result in ultrastructural changes in the small intestine, a decrease in intestinal enzyme activity and malabsorption of nutrients. The effects of cytotoxic drugs on the small intestinal structure and function are reviewed in more detail. The drugs discussed include the alkylating agents such as nitrogen mustard, cyclophosphamide, iphosphamide, 1,3-bis (2-chloroethyl)-1-nitrosourea and 1(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea. The effects of antimetabolites such as aminopterin, methotrexate, 5-fluoracil, cytosine arabinoside and 6-mercaptorpurine are also reviewed. Other drugs discussed were adriamycin, vincrinstine sulfate, vinblastine and hydroxyurea. Studies of the effects of combination chemotherapy on small intestinal structure and function are also described. It is concluded that chemotherapeutic drugs and radiation therapy may aggravate a malabsorptive state in view of their toxicity to the small intestinal cell, or may by themselves be responsible for malabsorption with resultant increase in cachexia and weight loss.

  9. Effects of cancer, radiotherapy and cytotoxic drugs on intestinal structure and function

    International Nuclear Information System (INIS)

    Shaw, M.T.; Spector, M.H.; Ladman, A.J.

    1979-01-01

    Intestinal malabsorption and the structural changes in the small intestine in relation to cancer, radiotherapy and cytotoxic drugs are reviewed. Primary intestinal malignancies are often associated with malabsorption; further studies have shown that tumours outside the gastrointestinal tract may also be accompanied by changes in intestinal structure resulting in malabsorption. Abdominal radiotherapy of cancer patients has been shown to result in ultrastructural changes in the small intestine, a decrease in intestinal enzyme activity and malabsorption of nutrients. The effects of cytotoxic drugs on the small intestinal structure and function are reviewed in more detail. The drugs discussed include the alkylating agents such as nitrogen mustard, cyclophosphamide, iphosphamide, 1,3-bis (2-chloroethyl)-1-nitrosourea and 1(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea. The effects of antimetabolites such as aminopterin, methotrexate, 5-fluoracil, cytosine arabinoside and 6-mercaptorpurine are also reviewed. Other drugs discussed were adriamycin, vincrinstine sulfate, vinblastine and hydroxyurea. Studies of the effects of combination chemotherapy on small intestinal structure and function are also described. It is concluded that chemotherapeutic drugs and radiation therapy may aggravate a malabsorptive state in view of their toxicity to the small intestinal cell, or may by themselves be responsible for malabsorption with resultant increase in cachexia and weight loss. (UK)

  10. Effects of radiotherapy on immunity in patients with localized carcinoma of the cervix uteri

    International Nuclear Information System (INIS)

    Hancock, B.W.; Bruce, L.; Heath, J.; Sugden, P.; Ward, A.M.

    1979-01-01

    To assess the effects of radiotherapy on immune status, a wide range of assessments have been performed on patients with localized carcinoma of the cervix uteri undergoing and initially responding clinically to radical pelvic radiotherapy. neutrophil function was essentially unchanged by treatment. Absolute neutrophil and lymphocyte counts fell after treatment and remained depressed 3 and 12 months following treatment. The proportions of T and B cells dropped with treatment but recovered to near-presentation levels during the follow-up period even though absolute counts remained depressed. In vitro tests of cellular immunity were depressed by treatment and remained so 3 and 12 months following treatment whereas skin test responses remained normal throughout the assessments. Inhibitory plasma effects were observed in photohaemagglutinin lymphocyte transformation studies on 4 untreated patients; at follow-up these effects were not evident. A variable response in immune indices has therefore been observed in patients in remission after treatment of localized carcinoma cervix stressing the importance of assessing several aspects of immune function and implying that persistent depression of certain indices does not adversely affect the host tumor response. In two patients relapsing after apparently good initial response, all aspects of immunological assessment (except serum immunoglobulin levels and neutrophil function) deteriorated

  11. Radiogenic Side Effects After Hypofractionated Stereotactic Photon Radiotherapy of Choroidal Melanoma in 212 Patients Treated Between 1997 and 2007

    Energy Technology Data Exchange (ETDEWEB)

    Dunavoelgyi, Roman [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Dieckmann, Karin [Department of Radiology, Medical University of Vienna, Vienna (Austria); Gleiss, Andreas [Section of Clinical Biometrics, Medical University of Vienna, Vienna (Austria); Sacu, Stefan; Kircher, Karl; Georgopoulos, Michael [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Georg, Dietmar [Department of Radiology, Medical University of Vienna, Vienna (Austria); Zehetmayer, Martin [Department of Ophthalmology, Medical University of Vienna, Vienna (Austria); Poetter, Richard [Department of Radiology, Medical University of Vienna, Vienna (Austria)

    2012-05-01

    Purpose: To evaluate side effects of hypofractionated stereotactic photon radiotherapy for patients with choroidal melanoma. Patients and Methods: Two hundred and twelve patients with choroidal melanoma unsuitable for ruthenium-106 brachytherapy or local resection were treated stereotactically at the Medical University of Vienna between 1997 and 2007 with a Linac with 6-MV photon beams in five fractions with 10, 12, or 14 Gy per fraction. Examinations for radiogenic side effects were performed at baseline and every 3 months in the first 2 years, then every 6 months until 5 years and then once a year thereafter until 10 years after radiotherapy. Adverse side effects were assessed using slit-lamp examination, funduscopy, gonioscopy, tonometry, and, if necessary, fundus photography and fluorescein angiography. Evaluations of incidence of side effects are based on an actuarial analysis. Results: One hundred and eighty-nine (89.2%) and 168 (79.2%) of the tumors were within 3 mm of the macula and the optic disc, respectively. The five most common radiotherapy side effects were retinopathy and optic neuropathy (114 cases and 107 cases, respectively), cataract development (87 cases), neovascular glaucoma (46 cases), and corneal epithelium defects (41 cases). In total, 33.6%, 38.5%, 51.2%, 75.5%, and 77.6% of the patients were free of any radiation retinopathy, optic neuropathy, cataract, neovascular glaucoma, or corneal epithelium defects 5 years after radiotherapy, respectively. Conclusion: In centrally located choroidal melanoma hypofractionated stereotactic photon radiotherapy shows a low to moderate rate of adverse long-term side effects comparable with those after proton beam radiotherapy. Future fractionation schemes should seek to further reduce adverse side effects rate while maintaining excellent local tumor control.

  12. Radiogenic Side Effects After Hypofractionated Stereotactic Photon Radiotherapy of Choroidal Melanoma in 212 Patients Treated Between 1997 and 2007

    International Nuclear Information System (INIS)

    Dunavoelgyi, Roman; Dieckmann, Karin; Gleiss, Andreas; Sacu, Stefan; Kircher, Karl; Georgopoulos, Michael; Georg, Dietmar; Zehetmayer, Martin; Poetter, Richard

    2012-01-01

    Purpose: To evaluate side effects of hypofractionated stereotactic photon radiotherapy for patients with choroidal melanoma. Patients and Methods: Two hundred and twelve patients with choroidal melanoma unsuitable for ruthenium-106 brachytherapy or local resection were treated stereotactically at the Medical University of Vienna between 1997 and 2007 with a Linac with 6-MV photon beams in five fractions with 10, 12, or 14 Gy per fraction. Examinations for radiogenic side effects were performed at baseline and every 3 months in the first 2 years, then every 6 months until 5 years and then once a year thereafter until 10 years after radiotherapy. Adverse side effects were assessed using slit-lamp examination, funduscopy, gonioscopy, tonometry, and, if necessary, fundus photography and fluorescein angiography. Evaluations of incidence of side effects are based on an actuarial analysis. Results: One hundred and eighty-nine (89.2%) and 168 (79.2%) of the tumors were within 3 mm of the macula and the optic disc, respectively. The five most common radiotherapy side effects were retinopathy and optic neuropathy (114 cases and 107 cases, respectively), cataract development (87 cases), neovascular glaucoma (46 cases), and corneal epithelium defects (41 cases). In total, 33.6%, 38.5%, 51.2%, 75.5%, and 77.6% of the patients were free of any radiation retinopathy, optic neuropathy, cataract, neovascular glaucoma, or corneal epithelium defects 5 years after radiotherapy, respectively. Conclusion: In centrally located choroidal melanoma hypofractionated stereotactic photon radiotherapy shows a low to moderate rate of adverse long-term side effects comparable with those after proton beam radiotherapy. Future fractionation schemes should seek to further reduce adverse side effects rate while maintaining excellent local tumor control.

  13. Effectiveness of fentanyl transdermal patch (fentanyl-TTS, durogegic) for radiotherapy induced pain and cancer pain: multi-center trial

    International Nuclear Information System (INIS)

    Shin, Seong Soo; Choi, Eun Kyung; Huh, Seung Jae

    2006-01-01

    To evaluate the effectiveness and safety of fentanyl-TTS in the management of radiotherapy induced acute pain and cancer pain treated with radiotherapy. Our study was open labelled prospective phase IV multi-center study, the study population included patients with more 4 numeric rating scale (NRS) score pain although managed with other analgesics or more than 6 NRS score pain without analgesics. Patients divided into two groups: patients with radiotherapy induced pain (Group A) and patients with cancer pain treated with radiotherapy (Group B). All patients received 25 ug/hr of fentanyl transdermal patch. Primary end point was pain relief: second end points were change in patient quality of life, a degree of satisfaction for patients and clinician, side effects. Between March 2005 and June 2005, 312 patients from 26 participating institutes were registered, but 249 patients completed this study. Total number of patients in each group was 185 in Group A, 64 in Group B. Mean age was 60 years and male to female ratio was 76:24. Severe pain NRS score at 2 weeks after the application of fentanyl was decreased from 7.03 to 4.01, ρ = 0.003. There was a significant improvement in insomnia, social functioning, and quality of life. A degree of satisfaction for patients and clinician was very high. The most common reasons of patients' satisfactions was good pain control. Ninety six patients reported side effect. Nausea was the most common side effect. There was no serious side effect. Fentanyl-TTS was effective in both relieving pain with good tolerability and improving the quality of life for patients with radiotherapy induced acute pain and cancer pain treated with radiotherapy. The satisfaction of the patients and doctors was good. There wa no major side effect

  14. Effectiveness of fentanyl transdermal patch (fentanyl-TTS, durogegic) for radiotherapy induced pain and cancer pain: multi-center trial

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seong Soo; Choi, Eun Kyung [University of Ulsan College of Medicine, Seoul (Korea, Republic of); Huh, Seung Jae [Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)] (and others)

    2006-12-15

    To evaluate the effectiveness and safety of fentanyl-TTS in the management of radiotherapy induced acute pain and cancer pain treated with radiotherapy. Our study was open labelled prospective phase IV multi-center study, the study population included patients with more 4 numeric rating scale (NRS) score pain although managed with other analgesics or more than 6 NRS score pain without analgesics. Patients divided into two groups: patients with radiotherapy induced pain (Group A) and patients with cancer pain treated with radiotherapy (Group B). All patients received 25 ug/hr of fentanyl transdermal patch. Primary end point was pain relief: second end points were change in patient quality of life, a degree of satisfaction for patients and clinician, side effects. Between March 2005 and June 2005, 312 patients from 26 participating institutes were registered, but 249 patients completed this study. Total number of patients in each group was 185 in Group A, 64 in Group B. Mean age was 60 years and male to female ratio was 76:24. Severe pain NRS score at 2 weeks after the application of fentanyl was decreased from 7.03 to 4.01, {rho} = 0.003. There was a significant improvement in insomnia, social functioning, and quality of life. A degree of satisfaction for patients and clinician was very high. The most common reasons of patients' satisfactions was good pain control. Ninety six patients reported side effect. Nausea was the most common side effect. There was no serious side effect. Fentanyl-TTS was effective in both relieving pain with good tolerability and improving the quality of life for patients with radiotherapy induced acute pain and cancer pain treated with radiotherapy. The satisfaction of the patients and doctors was good. There wa no major side effect.

  15. The relationship between external beam radiotherapy dose and chronic urinary dysfunction - A methodological critique

    International Nuclear Information System (INIS)

    Rosewall, Tara; Catton, Charles; Currie, Geoffrey; Bayley, Andrew; Chung, Peter; Wheat, Janelle; Milosevic, Michael

    2010-01-01

    Purpose: To perform a methodological critique of the literature evaluating the relationship between external beam radiotherapy dose/volume parameters and chronic urinary dysfunction to determine why consistent associations between dose and dysfunction have not been found. Methods and materials: The radiotherapy literature was reviewed using various electronic medical search engines with appropriate keywords and MeSH headings. Inclusion criteria comprised of; English language articles, published between 1999 and June 2009, incorporating megavoltage external beam photons in standard-sized daily fraction. A methodological critique was then performed, evaluating the factors affected in the quantification of radiotherapy dose and chronic urinary dysfunction. Results: Nine of 22 eligible studies successfully identified a clinically and statistically significant relationship between dose and dysfunction. Accurate estimations of external beam radiotherapy dose were compromised by the frequent use of dosimetric variables which are poor surrogates for the dose received by the lower urinary tract tissue and do not incorporate the effect of daily variations in isocentre and bladder position. The precise categorization of chronic urinary dysfunction was obscured by reliance on subjective and aggregated toxicity metrics which vary over time. Conclusions: A high-level evidence-base for the relationship between external beam radiotherapy dose and chronic urinary dysfunction does not currently exist. The quantification of the actual external beam dose delivered to the functionally important tissues using dose accumulation strategies and the use of objective measures of individual manifestations of urinary dysfunction will assist in the identification of robust relationships between dose and urinary dysfunction for application in widespread clinical practice.

  16. Applying failure mode effects and criticality analysis in radiotherapy: Lessons learned and perspectives of enhancement

    International Nuclear Information System (INIS)

    Scorsetti, Marta; Signori, Chiara; Lattuada, Paola; Urso, Gaetano; Bignardi, Mario; Navarria, Pierina; Castiglioni, Simona; Mancosu, Pietro; Trucco, Paolo

    2010-01-01

    Introduction: The radiation oncology process along with its unique therapeutic properties is also potentially dangerous for the patient, and thus it should be delivered under a systematic risk control. To this aim incident reporting and analysis are not sufficient for assuring patient safety and proactive risk assessment should also be implemented. The paper accounts for some methodological solutions, lessons learned and opportunities for improvement, starting from the systematic application of the failure mode effects and criticality analysis (FMECA) technique to the radiotherapy process of an Italian hospital. Materials and methods: The analysis, performed by a working group made of experts of the radiotherapy unit, was organised into the following steps: (1) complete and detailed analysis of the process (integration definition for function modelling); (2) identification of possible failure modes (FM) of the process, representing sources of adverse events for the patient; (3) qualitative risk assessment of FMs, aimed at identifying priorities of intervention; (4) identification and planning of corrective actions. Results: Organisational and procedural corrective measures were implemented; a set of safety indexes for the process was integrated within the traditional quality assurance indicators measured by the unit. A strong commitment of all the professionals involved was observed and the study revealed to be a powerful 'tool' for dissemination of patient safety culture. Conclusion: The feasibility of FMECA in fostering radiotherapy safety was proven; nevertheless, some lessons learned as well as weaknesses of current practices in risk management open to future research for the integration of retrospective methods (e.g. incident reporting or root cause analysis) and risk assessment.

  17. Clinical Effect of Human Papillomavirus Genotypes in Patients With Cervical Cancer Undergoing Primary Radiotherapy

    International Nuclear Information System (INIS)

    Wang, Chun-Chieh; Lai, Chyong-Huey; Huang, Huei-Jean; Chao, Angel; Chang, Chee-Jen; Chang, Ting-Chang; Chou, Hung-Hsueh; Hong, Ji-Hong

    2010-01-01

    Purpose: To study the prognostic value of the human papillomavirus (HPV) genotypes in cervical cancer patients undergoing radiotherapy. Patients and Methods: A total of 1,010 patients with cervical cancer after radiotherapy between 1993 and 2000 were eligible for this study. The HPV genotypes were determined by a genechip, which detects 38 types of HPV. The patient characteristics and treatment outcomes were analyzed using the Cox regression hazard model and classification and regression tree decision tree method. Results: A total of 25 genotypes of HPV were detected in 992 specimens (98.2%). The leading 8 types were HPV16, 58, 18, 33, 52, 39, 31, and 45. These types belong to two high-risk HPV species: alpha-7 (HPV18, 39, 45) and alpha-9 (HPV16, 31, 33, 52, 58). Three HPV-based risk groups, which were independent of established prognostic factors, such as International Federation of Gynecology and Obstetrics stage, age, pathologic features, squamous cell carcinoma antigen, and lymph node metastasis, were associated with the survival outcomes. The high-risk group consisted of the patients without HPV infection or the ones infected with the alpha-7 species only. Patients co-infected with the alpha-7 and alpha-9 species belonged to the medium-risk group, and the others were included in the low-risk group. Conclusion: The results of the present study have confirmed the prognostic value of HPV genotypes in cervical cancer treated with radiotherapy. The different effect of the alpha-7 and alpha-9 species on the radiation response deserves additional exploration.

  18. Disease specific stress of tumor patients at the beginning of radiotherapy. Effect on psychosocial support requirement

    International Nuclear Information System (INIS)

    Sehlen, S.; Hollenhorst, H.; Schymura, B.; Firsching, M.; Duehmke, E.; Herschbach, P.

    2001-01-01

    Purpose: Radiotherapy brings a tumor patient into a special life situation in which different variables play a role of often unknown importance. The goal of this study was to investigate disease specific stress of tumor patients at the beginning of radiotherapy with established psychodiagnostic questionnaires and to evaluate the effect on psychosocial support requirement in order to reduce stress and to improve quality of life and compliance during radiotherapeutical treatment. Patients and Methods: 732 patients were screened, of whom 446 (60.9%) fulfilled the criteria for inclusion (refusals 21.0%, low Karnofsky performance status 6.6%, management problems 3.4%, language barriers 3.0%, cognitive restrictions 2.6%, death 2.5%). Disease specific aspects of stress in the questionnaire (Fragebogen zur Belastung von Krebspatienten, FBK), life situation (LS) and self-defined care requirements (BB) were self-rated by patients with different tumor types before radiotherapy. Medical and sociodemographic data were also documented. We investigated 446 patients (262 male, 184 female; median age 60.0 years) with different diagnoses. Results: Stress was observed mainly due to reduction of efficiency, anxiety and pain on the subscales. Women had a significant higher stress on subscales of pain (p=0.016) and anxiety (p=0.009), patients younger than 45 years in the subscale information (p=0.002) and patients older than 45 and younger than 60 years in the subscale anxiety (p=0.002) and the total score (p=0.003). Patients with mamma carcinoma had the highest stress. The maximum percentages of patients under high stress were found for the subscales of efficiency (43%) and anxiety (40%). The support requirement was characterized by the need of more medical information and dialogue with the doctor. We saw a significant correlation of high stress and high care requirement. Conclusions: Psychosocial support should be founded on psychosocial stress diagnostic and self-defined care

  19. Protective effect of L-Cysteine upon leukopenic syndrome due to radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Jingu, K; Matsuura, K [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine; Bussaka, Y

    1981-08-01

    L-Cysteine, glutathione, inosine, and cepharanthin are the agents which have been widely used to prevent and treat the leukopenic syndrome following radiotherapy. Among these, the efficacy of inosine has been demonstrated in a double-blind comparative study. A double-blind controlled study of L-Cysteine compared to inosine and lactose-placebo was performed. Patients designated to receive radiotherapy for cancer of the lung, breast and uterine cervix were randomly allocated to 3 groups; namely, those to receive L-Cysteine 480 mg TID (CG group), inosine 1,800 mg TID (IN group) and placebo capsules (PL group) for 6 to 7 weeks. Among 159 cases, 152 were subjected to statistical analyses, and the latter consisted of 54 CG, 52 IN and 46 PL subjects. Any discrepancies among these 3 groups concerning sex, age, disease, WBC count, radiation procedure, or combined use of carcinostatics were negligible. According to the life-table analysis, the cumulative rates for the 3 groups were compared with respect to maintenance of WBC counts higher than 4,000/mm/sup 3/. Maintenance was best in the CG group, intermediate in the IN, and poorest in the PL group, the difference between CG and PL being statistically significant at the 5% level. Similar results were obtained in separate analyses of strata with and without concomitant carcinostatics. Furthermore, nearly the same results were obtained as those in the life-table analyses when data concerning efficacy and clinical usefulness as judged by physicians were analyzed. The present study indicates that the oral administration of L-Cysteine is safe and effective in preventing and treating leukopenic complications associated with radiotherapy.

  20. SU-F-T-359: Incorporating Dose Volume Histogram Prediction Into Auto-Planning for Volumetric-Modulated Arc Therapy in Rectal Cancer

    International Nuclear Information System (INIS)

    Li, K; Chen, X; Wang, J; Lu, S; Chen, Y; Hu, W

    2016-01-01

    Purpose: To incorporate dose volume histogram (DVH) prediction into Auto-Planning for volumetric-modulated arc therapy (VMAT) treatment planning and investigate the benefit of this new technique for rectal cancer. Methods: Ninety clinically accepted VMAT plans for patients with rectal cancer were selected and trained in the RapidPlan for DVH prediction. Both internal and external validations were performed before implementing the prediction model. A new VMAT planning method (hybrid-VMAT) was created with combining the DVH prediction and Auto-Planning. For each new patient, the DVH will be predicted and individual DVH constrains will be obtained and were exported as the original optimization parameters to the Auto-Planning (Pinnacle3 treatment planning system, v9.10) for planning. A total of 20 rectal cancer patients previously treated with manual VMAT (manual-VMAT) plans were replanned using this new method. Dosimetric comparisons were performed between manual VMAT and new method plans. Results: Hybrid-VMAT shows similar PTV coverage to manual-VMAT in D2%, D98% and HI (p>0.05) and superior coverage in CI (p=0.000). For the bladder, the means of V40 and mean dose are 36.0% and 35.6Gy for hybrid-VMAT and 42% and 38.0Gy for the manual-VMAT. For the left (right) femur, the means of V30 and mean dose are 10.6% (11.6%) and 17.9Gy (19.2Gy) for the hybrid-VMAT and 25.6% (24.1%) and 27.3Gy (26.2Gy) for the manual-VMAT. The hybrid-VMAT has significantly improved the organs at risk sparing. Conclusion: The integration of DVH prediction and Auto-Planning significantly improve the VMAT plan quality in the rectal cancer radiotherapy. Our results show the benefit of the new method and will be further investigated in other tumor sites.

  1. SU-F-T-359: Incorporating Dose Volume Histogram Prediction Into Auto-Planning for Volumetric-Modulated Arc Therapy in Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, K; Chen, X; Wang, J; Lu, S; Chen, Y; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To incorporate dose volume histogram (DVH) prediction into Auto-Planning for volumetric-modulated arc therapy (VMAT) treatment planning and investigate the benefit of this new technique for rectal cancer. Methods: Ninety clinically accepted VMAT plans for patients with rectal cancer were selected and trained in the RapidPlan for DVH prediction. Both internal and external validations were performed before implementing the prediction model. A new VMAT planning method (hybrid-VMAT) was created with combining the DVH prediction and Auto-Planning. For each new patient, the DVH will be predicted and individual DVH constrains will be obtained and were exported as the original optimization parameters to the Auto-Planning (Pinnacle3 treatment planning system, v9.10) for planning. A total of 20 rectal cancer patients previously treated with manual VMAT (manual-VMAT) plans were replanned using this new method. Dosimetric comparisons were performed between manual VMAT and new method plans. Results: Hybrid-VMAT shows similar PTV coverage to manual-VMAT in D2%, D98% and HI (p>0.05) and superior coverage in CI (p=0.000). For the bladder, the means of V40 and mean dose are 36.0% and 35.6Gy for hybrid-VMAT and 42% and 38.0Gy for the manual-VMAT. For the left (right) femur, the means of V30 and mean dose are 10.6% (11.6%) and 17.9Gy (19.2Gy) for the hybrid-VMAT and 25.6% (24.1%) and 27.3Gy (26.2Gy) for the manual-VMAT. The hybrid-VMAT has significantly improved the organs at risk sparing. Conclusion: The integration of DVH prediction and Auto-Planning significantly improve the VMAT plan quality in the rectal cancer radiotherapy. Our results show the benefit of the new method and will be further investigated in other tumor sites.

  2. Legal and technical regulations in radiation protection and their effects on radiotherapy

    International Nuclear Information System (INIS)

    Betz, B.

    1975-01-01

    During the last few years, new regulations and guidelines in the field of radiation protection have been issued which affect radiotherapy, too. On September 1st, 1973 the X-ray Ordinance became effective; a few weeks later, new guidelines for radiation protections when using radioactive substances in the field of medicine were published. Of particular topical interest is the appendix of these new guidelines, in which the principles of technical competence in radiation protection when handling radioactive substances in the field of medicine are laid down uniformly for the FRG. Amongst these more recent regulations, there is also the direction by the Minister of the Interior to put the operation of accelerators in the field of medicine according to section 19 of the Atomic Energy Act under the supervision of the state and to employ newly issued administrative guidelines. After a short survey on the radiation protection laws in force, a selection of important stipulations within the new legal regulations and guidelines is discussed with a view to their effects on radiotherapy. (orig./LN) [de

  3. Misonidazole in patients receiving radical radiotherapy: pharmacokinetic effects of phenytoin tumor response and neurotoxicity

    International Nuclear Information System (INIS)

    Moore, J.L.; Biol, F.I.; Patterson, I.C.M.; Dawes, P.J.D.K.; Henk, J.M.

    1982-01-01

    In 1978, a pilot study began of 29 patients with advanced tumors of the head and neck. The study showed an initial peripheral neuropathy rate of 55%, despite a dose limitation of 12 g/m 2 of misonidazole. Tumor response at 9 months was most encouraging. We are now able to examine tumor response and persistence of neuropathy in these patients 2 1/2 years after radical radiotherapy. The results are comparable with those obtained with hyperbaric oxygen in a clinical trial at this center during the 1970's. Neuropathy was a serious side effect but the drug phenytoin has been shown to shorten the half-life of misonidazole. We have examined the effect of phenytoin on the pharmacokinetics of misonidazole in 13 patients who received radical radiotherapy for advanced head and neck tumors or oesophageal tumors. Misonidazole was given in multiple doses, i.e. daily or weekly as it would be used in conventional therapy. Phenytoin was given either daily throughout treatment, or it was withdrawn during treatment. There were dramatic changes in the half-life of misonidazole, but the concentration at the time of irradiation was little affected. The significant changes in the half-life of misonidazole and the increased concentration of the metabolite desmethylmisonidazole are discussed

  4. Fluence map optimization (FMO) with dose-volume constraints in IMRT using the geometric distance sorting method.

    Science.gov (United States)

    Lan, Yihua; Li, Cunhua; Ren, Haozheng; Zhang, Yong; Min, Zhifang

    2012-10-21

    A new heuristic algorithm based on the so-called geometric distance sorting technique is proposed for solving the fluence map optimization with dose-volume constraints which is one of the most essential tasks for inverse planning in IMRT. The framework of the proposed method is basically an iterative process which begins with a simple linear constrained quadratic optimization model without considering any dose-volume constraints, and then the dose constraints for the voxels violating the dose-volume constraints are gradually added into the quadratic optimization model step by step until all the dose-volume constraints are satisfied. In each iteration step, an interior point method is adopted to solve each new linear constrained quadratic programming. For choosing the proper candidate voxels for the current dose constraint adding, a so-called geometric distance defined in the transformed standard quadratic form of the fluence map optimization model was used to guide the selection of the voxels. The new geometric distance sorting technique can mostly reduce the unexpected increase of the objective function value caused inevitably by the constraint adding. It can be regarded as an upgrading to the traditional dose sorting technique. The geometry explanation for the proposed method is also given and a proposition is proved to support our heuristic idea. In addition, a smart constraint adding/deleting strategy is designed to ensure a stable iteration convergence. The new algorithm is tested on four cases including head-neck, a prostate, a lung and an oropharyngeal, and compared with the algorithm based on the traditional dose sorting technique. Experimental results showed that the proposed method is more suitable for guiding the selection of new constraints than the traditional dose sorting method, especially for the cases whose target regions are in non-convex shapes. It is a more efficient optimization technique to some extent for choosing constraints than the dose

  5. Use of normalized total dose to represent the biological effect of fractionated radiotherapy

    International Nuclear Information System (INIS)

    Flickinger, J.C.; Kalend, A.

    1990-01-01

    There are currently a number of radiobiological models to account for the effects of dose fractionation and time. Normalized total dose (NTD) is not another new model but is a previously reported, clinically useful form in which to represent the biological effect, determined by any specific radiobiological dose-fractionation model, of a course of radiation using a single set of standardized, easily understood terminology. The generalized form of NTD reviewed in this paper describes the effect of a course of radiotherapy administered with nonstandard fractionation as the total dose of radiation in Gy that could be administered with a given reference fractionation such as 2 Gy per fraction, 5 fractions per week that would produce an equivalent biological effect (probability of complications or tumor control) as predicted by a given dose-fractionation formula. The use of normalized total dose with several different exponential and linear-quadratic dose-fraction formulas is presented. (author). 51 refs.; 1 fig.; 1 tab

  6. Treatment planning for heavy ion radiotherapy: calculation and optimization of biologically effective dose

    International Nuclear Information System (INIS)

    Kraemer, M.; Scholz, M.

    2000-09-01

    We describe a novel approach to treatment planning for heavy ion radiotherapy based on the local effect model (LEM) which allows to calculate the biologically effective dose not only for the target region but for the entire irradiation volume. LEM is ideally suited to be used as an integral part of treatment planning code systems for active dose shaping devices like the GSI raster scan system. Thus, it has been incorporated into our standard treatment planning system for ion therapy (TRiP). Single intensity modulated fields can be optimized with respect to homogeneous biologically effective dose. The relative biological effectiveness (RBE) is calculated separately for each voxel of the patient CT. Our radiobiologically oriented code system is in use since 1995 for the planning of irradiation experiments with cell cultures and animals such as rats and minipigs. Since 1997 it is in regular and successful use for patient treatment planning. (orig.)

  7. Use of normalized total dose to represent the biological effect of fractionated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Flickinger, J C; Kalend, A [Pittsburgh University School of Medicine (USA). Department of Radiation Oncology Pittsburg Cancer Institute (USA)

    1990-03-01

    There are currently a number of radiobiological models to account for the effects of dose fractionation and time. Normalized total dose (NTD) is not another new model but is a previously reported, clinically useful form in which to represent the biological effect, determined by any specific radiobiological dose-fractionation model, of a course of radiation using a single set of standardized, easily understood terminology. The generalized form of NTD reviewed in this paper describes the effect of a course of radiotherapy administered with nonstandard fractionation as the total dose of radiation in Gy that could be administered with a given reference fractionation such as 2 Gy per fraction, 5 fractions per week that would produce an equivalent biological effect (probability of complications or tumor control) as predicted by a given dose-fractionation formula. The use of normalized total dose with several different exponential and linear-quadratic dose-fraction formulas is presented. (author). 51 refs.; 1 fig.; 1 tab.

  8. Relationship between radiation effect for carcinoma of the esophagus and x-ray findings before and after radiotherapy

    International Nuclear Information System (INIS)

    Morita, Kozo; Obata, Yasunori; Watanabe, Michiko; Karasawa, Kazuo; Takagi, Iwao

    1980-01-01

    From 1970 through 1978, 95 patients with carcinoma of the esophagus were treated with irradiation alone and/or combined with the administration of Bleomycin, preoperatively. On the basis of the histological analysis of the surgical specimen, the relationship between radiation effect for the primary tumor and the x-ray findings before and after the radiotherapy was investigated. The radiotherapy was the most effective for the superficial and tumorous type on the x-ray findings before treatment. The tumorous protruded subtype in the serrated type was more radiosensitive than the ulcerative subtype. The same tendency was also observed in the spiral type. The narrowing of the esophagus (funnelled type) and the ulceration were the most unsuitable signs for the radiotherapy. (author)

  9. Side effects of radiotherapy in breast cancer patients. The Internet as an information source

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, S. [Medical Practice for Radiotherapy and Radiation Oncology, Hannover (Germany); University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); Kaesmann, L.; Rades, D. [University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); Fahlbusch, F.B. [Friedrich-Alexander-University of Erlangen-Nuernberg, Department of Pediatrics and Adolescent Medicine, Erlangen (Germany); Vordermark, D. [University Hospital Halle (Saale), Department of Radiation Oncology, Halle (Saale) (Germany)

    2018-02-15

    Breast cancer is the most common cancer type among women necessitating adjuvant radiotherapy. As the Internet has become a major source of information for cancer patients, this study aimed to evaluate the quality of websites giving information on side effects of radiotherapy for breast cancer patients. A patients' search for the English terms ''breast cancer - radiotherapy - side effects'' and the corresponding German terms ''Brustkrebs - Strahlentherapie - Nebenwirkungen'' was carried out twice (5 months apart) using the search engine Google. The first 30 search results each were evaluated using the validated 16-question DISCERN Plus instrument, the Health on the Net Code of Conduct (HONcode) certification and the Journal of the American Medical Association (JAMA) benchmark criteria. The overall quality (DISCERN score) of the retrieved websites was further compared to queries via Bing and Yahoo search engines. The DISCERN score showed a great range, with the majority of websites ranking fair to poor. Significantly superior results were found for English websites, particularly for webpages run by hospitals/universities and nongovernmental organizations (NGO), when compared to the respective German categories. In general, only a minority of websites met all JAMA benchmarks and was HONcode certified (both languages). We did not determine a relevant temporal change in website ranking among the top ten search hits, while significant variation occurred thereafter. Mean overall DISCERN score was similar between the various search engines. The Internet can give breast cancer patients seeking information on side effects of radiotherapy an overview. However, based on the currently low overall quality of websites and the lack of transparency for the average layperson, we emphasize the value of personal contact with the treating radio-oncologist in order to integrate and interpret the information found online. (orig.) [German

  10. Symptom resolution, tumor control, and side effects following postoperative radiotherapy for pituitary macroadenomas

    International Nuclear Information System (INIS)

    Rush, Stephen; Cooper, Paul R.

    1997-01-01

    This study reports the outcome of 70 patients who were treated by a consistent treatment plan of surgery and postoperative radiotherapy (RT) for pituitary macroadenomas in the modern era [computed tomographic scan or magnetic resonance imaging (MRI), dopamine agonist therapy (DA) added as indicated, and immunohistochemical staining]. Sixty-two patients underwent transsphenoidal surgery (vs. transcranial surgery) and 61 received 45-Gy/25 fractions postoperatively (vs. other dose fractionation schemes). Twenty-four patients received DA for prolactin-secreting tumors. With a median follow-up of 8 years (range 2-15), 68 patients have experienced continuous control of their tumors. Most symptoms related to mass effect abated, while physiologic symptoms such as amenorrhea from markedly elevated prolactin levels tended to persist. Treatment-induced hypopituitarism occurred in 42% of the patients at risk. No patients in this series have died as a result of their pituitary tumor. No gross neuropsychologic dysfunction after treatment has been noted. While it is possible at this time with serial MRI to withhold postoperative RT and observe some patients who have had a 'gross total' resection of a macroadenoma, the therapeutic ratio for surgery and adjuvant radiotherapy for patients with nonfunctional tumors as well as select patients with secretory macroadenomas is favorable

  11. Obligatory information of patients on the possible side effects of a radiotherapy

    International Nuclear Information System (INIS)

    Schramm, S.

    1991-01-01

    The author gives a critical comment on the judgment of December 12, 1989, by the Federal High Court (BGH), which refers to the obligation to inform a patient about side effects of a radiotherapy. The author discusses the need to explain radiation risks, the principles of giving information on risks, and the judicial assessment given by the BGH. The comment primarily deals with failures to comply with the duty to inform a patient, aspects of the alternative, lawful procedure, and questions such as the burden of proof and the duty of the parties to substantiate their claims. The BGH in its judgment denied the duty to give information for the following case: The patient who took legal action had received ambulant telecobalt radiation treatments of 300 rd (3 Gy) each, amounting to a dose of 4200 rd (42 Gy). As a result, the woman suffers from a nerve lesion in the right arm, which is a substantial handicap. The patient's action for material and immaterial damages was filed on the grounds that there was no indication of a radiotherapy, and no information was given about the risks; the action was dismissed. (RST/HP) [de

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

    International Nuclear Information System (INIS)

    Gulliford, Sarah L.; Webb, Steve; Rowbottom, Carl G.; Corne, David W.; Dearnaley, David P.

    2004-01-01

    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

  13. The effect of surgery and radiotherapy on outcome of anaplastic thyroid carcinoma.

    Science.gov (United States)

    Pierie, Jean-Pierre E N; Muzikansky, Alona; Gaz, Randall D; Faquin, William C; Ott, Mark J

    2002-01-01

    Anaplastic thyroid carcinoma (ATC) is an aggressive rare tumor. We analyzed our experience for prognosis and the effect of surgery and radiotherapy on patients with ATC. We conducted a retrospective review of all patients (n = 67) with ATC treated at a tertiary care center from 1969 to 1999. Survivor median follow-up was 51 months. Tumor and patient characteristics and therapy were assessed for effect on survival by multivariate analysis. Patients presented with a neck mass (99%), change of voice (51%), dysphagia (33%), and dyspnea (28%). Surgery was performed in 44 of 67 patients, with 12 complete resections. The 6-month and 1- and 3-year survival rates were 92%, 92%, and 83% after complete resection; 53%, 35%, and 0% after debulking; and 22%, 4%, and 0% after no resection, respectively (P 45 Gy improved survival as compared with a lower dose (P = .02). Multivariate analysis showed that age 45 Gy improves outcome.

  14. 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.)

  15. Amino acid transport system - A substrate predicts the therapeutic effects of particle radiotherapy.

    Directory of Open Access Journals (Sweden)

    Tomoya Uehara

    Full Text Available L-[methyl-11C]Methionine (11C-Met is useful for estimating the therapeutic efficacy of particle radiotherapy at early stages of the treatment. Given the short half-life of 11C, the development of longer-lived 18F- and 123I-labeled probes that afford diagnostic information similar to 11C-Met, are being sought. Tumor uptake of 11C-Met is involved in many cellular functions such as amino acid transport System-L, protein synthesis, and transmethylation. Among these processes, since the energy-dependent intracellular functions involved with 11C-Met are more reflective of the radiotherapeutic effects, we evaluated the activity of the amino acid transport System-A as an another energy-dependent cellular function in order to estimate radiotherapeutic effects. In this study, using a carbon-ion beam as the radiation source, the activity of System-A was evaluated by a specific System-A substrate, alpha-[1-14C]-methyl-aminoisobutyric acid (14C-MeAIB. Cellular growth and the accumulation of 14C-MeAIB or 14C-Met were evaluated over time in vitro in cultured human salivary gland (HSG tumor cells (3-Gy or in vivo in murine xenografts of HSG tumors (6- or 25-Gy before and after irradiation with the carbon-ion beam. Post 3-Gy irradiation, in vitro accumulation of 14C-Met and 14C-MeAIB decreased over a 5-day period. In xenografts of HSG tumors in mice, tumor re-growth was observed in vivo on day-10 after a 6-Gy irradiation dose, but no re-growth was detected after the 25-Gy irradiation dose. Consistent with the growth results, the in vivo tumor accumulation of 14C-MeAIB did not decrease after the 6-Gy irradiation dose, whereas a significant decrease was observed after the 25-Gy irradiation dose. These results indicate that the activity of energy dependent System-A transporter may reflect the therapeutic efficacy of carbon-ion radiotherapy and suggests that longer half-life radionuclide-labeled probes for System-A may also provide widely available probes to

  16. Patients and radiotherapy

    International Nuclear Information System (INIS)

    Eardley, A.

    1986-01-01

    The results of interviews with thirty discharged patients who had undergone radical radiotherapy for cancer of the head and neck are presented. Patients were asked whether their side-effects had got worse or had stayed the same, what effect their side effects had had on eating and drinking and whether they had felt depressed during this period. Measures which could be taken to improve patients' experiences of radiotherapy are discussed. (U.K.)

  17. Protection of Salivary Function by Concomitant Pilocarpine During Radiotherapy: A Double-Blind, Randomized, Placebo-Controlled Study

    International Nuclear Information System (INIS)

    Burlage, Fred R.; Roesink, Judith M.; Kampinga, Harm H.; Coppes, Rob P.; Terhaard, Chris; Langendijk, Johannes A.; Luijk, Peter van; Stokman, Monique A.; Vissink, Arjan

    2008-01-01

    Purpose: To investigate the effect of concomitant administration of pilocarpine during radiotherapy for head-and-neck squamous cell carcinoma (HNSCC) on postradiotherapy xerostomia. Methods and Materials: A prospective, double blind, placebo-controlled randomized trial including 170 patients with HNSCC was executed to study the protective effect of pilocarpine on radiotherapy-induced parotid gland dysfunction. The primary objective endpoint was parotid flow rate complication probability (PFCP) scored 6 weeks, 6 months, and 12 months after radiotherapy. Secondary endpoints included Late Effects of Normal Tissue/Somatic Objective Management Analytic scale (LENT SOMA) and patient-rated xerostomia scores. For all parotid glands, dose-volume histograms were assessed because the dose distribution in the parotid glands is considered the most important prognostic factor with regard to radiation-induced salivary dysfunction. Results: Although no significant differences in PFCP were found for the two treatments arms, a significant (p = 0.03) reduced loss of parotid flow 1 year after radiotherapy was observed in those patients who received pilocarpine and a mean parotid dose above 40 Gy. The LENT SOMA and patient-rated xerostomia scores showed similar trends toward less dryness-related complaints for the pilocarpine group. Conclusions: Concomitant administration of pilocarpine during radiotherapy did not improve the PFCP or LENT SOMA and patient-rated xerostomia scores. In a subgroup of patients with a mean dose above 40 Gy, pilocarpine administration resulted in sparing of parotid gland function. Therefore, pilocarpine could be provided to patients in whom sufficient sparing of the parotid is not achievable

  18. Assessment of systemic effects of ginger on salivation in patients with post-radiotherapy xerostomia

    Directory of Open Access Journals (Sweden)

    Goli Chamani

    2017-07-01

    Full Text Available BACKGROUND AND AIM: Our aim was to assess the clinical efficacy of ginger capsule (Zintoma herbal capsule in the relief of symptoms in patients with post-radiotherapy xerostomia. METHODS: This study was a randomized double-blind, parallel clinical trial of ginger usage in patients with post-radiotherapy xerostomia. Sixty-one subjects were selected from patients with xerostomia of Imam Khomeini Cancer Institute, Tehran, Iran. Subject-based dry mouth scores derived from 100 mm visual analogue scales (VAS were recorded at baseline. Patients also completed a questionnaire on the first visit regarding the symptoms of xerostomia. The patients received ginger capsule (30 persons or placebo (31 persons three times daily over a 2-weeks period. At the end of day 14, dry mouth scores derived from VAS were recorded again and patients responded to the additional variables regarding dry mouth symptoms and quality of life issues. P < 0.05 was considered significant. Data were analyzed using SPSS. RESULTS: The mean treatment effect on day 14 was 33.7 ± 20.9 mm in the ginger group and 23.6 ± 17.3 mm in the placebo group. The analysis indicated marginally significant improvement of xerostomia with ginger prescription (P = 0.057. At the end of intervention there was no significant difference between the two groups regarding improvement of quality of life or dry mouth symptoms. CONCLUSION: It seems that ginger could be helpful in the treatment of xerostomia. Since ginger is considered a safe herbal medicine with only few and insignificant adverse/side effects further studies in larger group of patients are recommended to provide the effect of ginger on different complaints of xerostomia.

  19. Effect of fractionated radiotherapy using a hypoxic cell radiosensitizer, RK-28, on experimental murine tumor

    International Nuclear Information System (INIS)

    Tanaka, Shukaku

    1990-01-01

    The effect of a hypoxic cell radiosensitizer RK-28, on fractionated radiotherapy was studied using mice with implanted tumors. Experimental animal tumors were third generation isoplants of a mammary carcinoma which arose spontaneously in a C 3 H/He mouse. RK-28 was given to the mice at two dosages: 0.4 mg/g,b.wt. and 0.2 mg/g.b.wt. Total dose of irradiation was 20 Gy which was divided into the first 10 Gy irradiation and the second 10 Gy performed after a proper time interval such as 1, 24, 48 and 72 hours after the first 10 Gy irradiation. Tumor growth was evaluated by TGT 50 /3 times, which was defined as the time required for 50% of the tumors to regrow to the 3 times value of its initial volume. Tumor volume was measured every day and TGT 50 /3 times was calculated by logit analysis method. No significant differences were found in the TGT 50 /3 times among the groups treated by radiation alone, those treated by RK-administration alone and those without any treatment. TGT 50 value of control group without any treatment was 3.40 (days). TGT 50 value of another group treated by RK-28 alone was 3.46. and TGT 50 value of 20 Gy X-ray irradiation alone was 10.23. Under the fractionated X-ray irradiation alone, TGT 50 values of the various time interval such as 9, 14, 48 and 72 hours were 11.26, 10.42, 12.14 and 1.10. Under the combined treatment of the fractionated X-ray irradiation and RK-28 administration, TGT 50 values were 17.84, 16.42, 16.59 and 17.49. These TGT 50 /3 times values showed that RK-28 had a radiosensitizing effect when given with fractionated radiotherapy even at lower doses of RK-28 administration and radiation. Therefore, it was suggested that fractionated radiotherapy using RK-28 was useful in the cancer treatment. (author) 52 refs

  20. Long-term effects of radiotherapy for acromegaly on circulating prolactin

    International Nuclear Information System (INIS)

    Ciccarelli, E.; Corsello, S.M.; Besser, G.M.; Wass, J.A.H.; Plowman, P.N.; Jones, A.E.; Touzel, R.; Rees, L.H.

    1989-01-01

    In 61 acromegalic patients, serum PRL was assessed (off medical treatment) before and 2 to 12 (mean 6 p years after external beam radiotherapy. Before radiotherapy elevated PRL levels were present in 22 of 35 males (63%) and 12 of 26 females (46%) and were above 1000 mU/l in 11 males and 5 females. When studied for up to 5 years after radiotherapy, 22 or 23 (96%) patients who had not had surgery and who had normal PRL preradiotherapy showed an increased PRL level and this was also seen in 17 or 27 (63%) who had hyperprolactinaemic initially. In contrast, 10 of 27 patients (37%) who had elevated pre-radiotherapy levels (all greater than 1000 mU/l) had a reduction in PRL values after radiotherapy. In all 11 patients who underwent surgery before radiotherapy, an increase in PRL was seen after radiotherapy. In the 21 patients followed for 10-12 years, the peak PRL value occurred 1-6 years after radiotherapy. After this, a progressive reduction of PRL to normal was seen. Normal levels were reached 4 to 10 years after radiotherapy. No correlation was found between pretreatment PRL values and final GH values in the whole group, nor between changes in PRL and the development of Impaired ACTH or TSH secretion. Thus, different patterns of PRL behaviour suggest that radiotherapy treatment may either produce hyperprolactinemia from mild hypothalamic damage or ablate PRL secreting cells if they were present in the tumour before treatment. These changes do not predict final GH results or the development of hypopituitarism after radiotherapy. (author)

  1. Long-term effects of radiotherapy for acromegaly on circulating prolactin

    Energy Technology Data Exchange (ETDEWEB)

    Ciccarelli, E.; Corsello, S.M.; Besser, G.M.; Wass, J.A.H. (Department of Endocrinology, St. Bartholomew' s Hospital, West Smithfield, London (UK)); Plowman, P.N.; Jones, A.E. (Department of Radiotherapy, St. Bartholomew' s Hospital, West Smithfield, London (UK)); Touzel, R.; Rees, L.H. (Department of Chemical Endocrinology, St. Bartholomew' s Hospital, West Smithfield, London (UK))

    1989-01-01

    In 61 acromegalic patients, serum PRL was assessed (off medical treatment) before and 2 to 12 (mean 6 p) years after external beam radiotherapy. Before radiotherapy elevated PRL levels were present in 22 of 35 males (63%) and 12 of 26 females (46%) and were above 1000 mU/l in 11 males and 5 females. When studied for up to 5 years after radiotherapy, 22 or 23 (96%) patients who had not had surgery and who had normal PRL preradiotherapy showed an increased PRL level and this was also seen in 17 or 27 (63%) who had hyperprolactinaemic initially. In contrast, 10 of 27 patients (37%) who had elevated pre-radiotherapy levels (all greater than 1000 mU/l) had a reduction in PRL values after radiotherapy. In all 11 patients who underwent surgery before radiotherapy, an increase in PRL was seen after radiotherapy. In the 21 patients followed for 10--12 years, the peak PRL value occurred 1--6 years after radiotherapy. After this, a progressive reduction of PRL to normal was seen. Normal levels were reached 4 to 10 years after radiotherapy. No correlation was found between pretreatment PRL values and final GH values in the whole group, nor between changes in PRL and the development of Impaired ACTH or TSH secretion. Thus, different patterns of PRL behaviour suggest that radiotherapy treatment may either produce hyperprolactinemia from mild hypothalamic damage or ablate PRL secreting cells if they were present in the tumour before treatment. These changes do not predict final GH results or the development of hypopituitarism after radiotherapy. (author).

  2. Effect of megestrol acetate and prepulsid on nutritional improvement in patients with head and neck cancers undergoing radiotherapy

    International Nuclear Information System (INIS)

    Chen, Hui-Chun; Leung, Stephen Wan; Wang, Chong-Jong; Sun, Li-Min; Fang, Fu-Min; Hsu, Jia-Hwa

    1997-01-01

    Background and purpose: Anorexia is a common problem in cancer patients who receive radiotherapy. In this current study, we attempt to determine the effect of megestrol acetate and prepulsid on appetite and nutritional improvement in patients with head and neck cancers undergoing radiotherapy. Materials and Methods: One hundred twenty-nine consecutive patients with head and neck cancers treated between July 1993 and June 1994 were prospectively randomized to receive either megestrol acetate, 40 mg qid (megace group), prepulsid, 5 mg tid (cisapride group), or a placebo treatment (control group) during radiotherapy. Before radiotherapy, body weight (kg), appetite score, performance status, biochemical parameters and hematological parameters were evaluated, and the above-noted clinical and biochemical parameters were assessed and recorded every other week. All patients received 6- 10 MV X-rays or Co-60 γ-ray to head and neck region for a full course of radiotherapy, 61.2-75.6 Gy/7-9 weeks. Results: Forty-eight patients were enrolled in the megace group, 41 patients in the cisapride group, and 40 patients in the control group. At the 2nd, 4th, 6th and 8th week, as the radiation dose escalated, the megace group had significantly less body weight loss than did the cisapride and control groups (P = 0.045, 0.024, 0.006, 0.003, respectively). The appetite scores of the megace group were significantly higher than those of the cisapride and control groups (P 0.0001). However, there were no statistically significant differences in the change of albumin level among these three groups at the 2nd, 4th, 6th and 8th week (P > 0.05, respectively). Conclusions: Megestrol acetate can significantly decrease the degree of body weight loss, and can prevent the deterioration of appetite in patients with head and neck cancers receiving radiotherapy. However, prepulsid lacks the above-mentioned clinical benefits

  3. Comparing the effects of conventional and hypofractionated radiotherapies on early skin toxicity and cosmetic outcomes after breast cancer conserving surgery

    Directory of Open Access Journals (Sweden)

    Amouzegar Hashemi F

    2012-12-01

    Full Text Available Background: The high number of breast cancer patients who receive radiation therapy after surgery has caused many to think about a shorter period of radiotherapy, which can significantly reduce the radiotherapy machine time, labor hours, and fewer patient visits. This study was designed to evaluate the acute skin effects and cosmetic outcomes of short course radiotherapy in early-stage breast cancer in comparison with the conventional treatment method.Methods: Fifty-two patients with operable breast cancer (pT1-3pN0M0 who underwent breast conservation surgery in Tehran Cancer Institute during January 2011 to January 2012, were randomly assigned to undergo radiotherapy by either receiving conventional treatment (dose: 50 Gy in 25 fractions with subsequent electron boost or a short-course hypofractionated radiotherapy (dose: 42.5 Gy in 16 fractions and a subsequent electron boost.Results: There were no skin changes during the first or the second week of treatment in the two groups. Cutaneous complications began after the third week as grade 1 skin toxicity after termination of the short-course radiotherapy but there were no difference in complication rate after four weeks of treatment. Six months and one year after treatment, there were no differences in terms of skin complications or cosmetic outcomes between the two groups.Conclusion: Although the use of a whole-breast irradiation with a hypofractionated schedule was associated with desirable outcomes, in term of skin toxicity and cosmetics, but longer follow-up periods with larger sample sizes are needed to confirm these results.

  4. Total and single doses influence the effectiveness of radiotherapy in palliative treatment of plasmacytoma

    International Nuclear Information System (INIS)

    Stoelting, T.; Knauerhase, H.; Klautke, G.; Kundt, G.; Fietkau, R.

    2008-01-01

    Purpose: in a retrospective analysis of radiotherapy of plasmacytomas, the effectiveness and the prognostic factors in regard to pain reduction and recalcification were evaluated. Patients and methods: 138 patients (70 women, 68 men; 15-86 years, median 61 years) were irradiated at 272 target volumes (TVs) from January 1970 to December 2003. Results: in 192/225 TVs (85.3%), there was a pain reduction. The recalcification rate was 44.7% (51/114 TVs). Significant parameters for pain relief in the multivariate analysis were completeness of therapy (odds ratio [OR] 87.8; p 1 year and an osteolysis at risk of fracture, should be treated with doses up to 40-50 Gy (20-25 x 2 Gy), in order to achieve the best possible recalcification and pain relief. (orig.)

  5. Effectiveness of purified sulfur intake per os to reduce a reaction in radiotherapy of uterine cervix

    International Nuclear Information System (INIS)

    Smirnova, O.V.; Saliev, V.P.; Klemparskaya, N.N.; Dobronravova, N.N.

    1991-01-01

    Theoretical basis of this work is the development of autosensitization in exposure to ionizing radiation and well-known desensitizing action of sulfuric agents. To reduce clinical manifestations of a side reaction to combined radiotherapy 34 women with diagnosis of cervical cancer were given 0.5-1 g of purified sulfur mixed with 0.25 g of glucose in the morning every 2-3 hours before irradiation, per os; 24 patients received placebo, in 21 patients no protective means were used. All 79 patients were given unified adjuvant therapy and diet No.15. A significant decrease in the reaction to therapeutic irradiation was noted in the study group. No side effects were observed

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

    International Nuclear Information System (INIS)

    Que, W; Kung, J; Dai, J

    2004-01-01

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

  7. Radiotherapy injuries in children

    International Nuclear Information System (INIS)

    Kalifa, G.; Bennet, J.; Couanet, D.; Masselot, J.

    1985-01-01

    Side effects of radiotherapy in pediatrics are reviewed including bone injuries and radio-induced bone tumors; nervous system injuries with emphasis on hypothalamus, pituitary gland, brain and spinal cord; lung, digestive system and urinary tract injuries [fr

  8. Radiotherapy for vertebral metastases. Analysis of symptoms and clinical effects by MR imaging

    International Nuclear Information System (INIS)

    Sugiyama, Akira

    1994-01-01

    Fifty patients with 63 symptomatic vertebral metastasis (18 sites: pain only, 28 sites: radiculopathy with pain, 17 sites: myelopathy) were treated by radiotherapy. Primary lesions were located in the lung (9 cases), breast (9), colorectal area (9), prostate (7) and so on. We correlated the radiologic findings, symptoms and clinical effects with metastatic features which were classified into 4 types by MR imaging: non-deformity, expanding, vertebral collapse, and destructive mass. Each type of metastasis was accompanied with or without epidural tumor. Osteolytic metastases were apt to create features of deformity (expanding type: 18 vertebrae, vertebral collapse type: 17, destructive mass type: 9). The features of osteoblastic metastases were no deformity (18 vertebrae) and expanding type (2). The symptom of pain only occurred most frequently in the lumbosacral spine. The vertebral body deformity of symptomatic sites was relatively slight (non-deformity type: 6 sites, expanding type: 6, vertebral collapse type: 6), and epidural tumors were seen at only 2 sites. The effect of radiotherapy was excellent (complete pain relief: 64.7%, partial pain relief: 29.4%). Radiculopathy occurred most frequently in the lumber spine. Vertebral body deformity was noted in most symptomatic sites (expanding type: 9 sites, vertebral collapse type: 10, destructive mass type: 2). Complete relief was obtained in 6 sites (22.2%), partial relief in 18 (63.0%). Myelopathy occurred most often in the thoracic spine, followed by the lumbar spine. The vertebral body deformity was severe (expanding: 3 cases, vertebral collapse type: 3, destructive mass type: 6). Epidural tumors were also present in all but one case. Six of 13 patients treated with radiation alone improved. These 6 patients had non-deformity or expanding types with epidural tumor. No improvement was seen in the vertebral collapse type with epidural tumor or destructive mass type. (author)

  9. Total and single doses influence the effectiveness of radiotherapy in palliative treatment of plasmacytoma

    Energy Technology Data Exchange (ETDEWEB)

    Stoelting, T.; Knauerhase, H.; Klautke, G. [Dept. of Radiotherapy, Univ. of Rostock (Germany); Kundt, G. [Inst. for Medical Informatics and Biometry, Univ. of Rostock (Germany); Fietkau, R. [Dept. of Radiotherapy, Univ. of Rostock (Germany); Dept. of Radiotherapy, Univ. of Erlangen (Germany)

    2008-09-15

    Purpose: in a retrospective analysis of radiotherapy of plasmacytomas, the effectiveness and the prognostic factors in regard to pain reduction and recalcification were evaluated. Patients and methods: 138 patients (70 women, 68 men; 15-86 years, median 61 years) were irradiated at 272 target volumes (TVs) from January 1970 to December 2003. Results: in 192/225 TVs (85.3%), there was a pain reduction. The recalcification rate was 44.7% (51/114 TVs). Significant parameters for pain relief in the multivariate analysis were completeness of therapy (odds ratio [OR] 87.8; p < 0.001 vs. interruption), patients < 60 years (OR 23.0; p < 0.001 vs. {>=} 70 years), and a single dose of 2 Gy (OR 11.0; p = 0.027 vs. 4-15.0 Gy). Significant parameters for recalcification in the multivariate analysis were concurrent chemotherapy (OR 12.3; p < 0.001 vs. no chemotherapy), no fractures in the TV (OR 5.9; p < 0.004 vs. fracture), and a dose of 40-< 50 Gy (OR 21.9; p = 0.035 vs. < 30 Gy) or {>=} 50 Gy (OR 26.4; p = 0.033 vs. < 30 Gy). Conclusion: radiotherapy is a very effective palliative treatment. Patients with a reduced general condition, with multiple bone lesions and a poor prognosis profit from short-term schemes (e.g., 1 x 8 Gy to 10 x 3 Gy). Patients in good general condition with a life expectancy of > 1 year and an osteolysis at risk of fracture, should be treated with doses up to 40-50 Gy (20-25 x 2 Gy), in order to achieve the best possible recalcification and pain relief. (orig.)

  10. The effects of radiotherapy treatment uncertainties on the delivered dose distribution and tumour control probability

    International Nuclear Information System (INIS)

    Booth, J.T.; Zavgorodni, S.F.; Royal Adelaide Hospital, SA

    2001-01-01

    Uncertainty in the precise quantity of radiation dose delivered to tumours in external beam radiotherapy is present due to many factors, and can result in either spatially uniform (Gaussian) or spatially non-uniform dose errors. These dose errors are incorporated into the calculation of tumour control probability (TCP) and produce a distribution of possible TCP values over a population. We also study the effect of inter-patient cell sensitivity heterogeneity on the population distribution of patient TCPs. This study aims to investigate the relative importance of these three uncertainties (spatially uniform dose uncertainty, spatially non-uniform dose uncertainty, and inter-patient cell sensitivity heterogeneity) on the delivered dose and TCP distribution following a typical course of fractionated external beam radiotherapy. The dose distributions used for patient treatments are modelled in one dimension. Geometric positioning uncertainties during and before treatment are considered as shifts of a pre-calculated dose distribution. Following the simulation of a population of patients, distributions of dose across the patient population are used to calculate mean treatment dose, standard deviation in mean treatment dose, mean TCP, standard deviation in TCP, and TCP mode. These parameters are calculated with each of the three uncertainties included separately. The calculations show that the dose errors in the tumour volume are dominated by the spatially uniform component of dose uncertainty. This could be related to machine specific parameters, such as linear accelerator calibration. TCP calculation is affected dramatically by inter-patient variation in the cell sensitivity and to a lesser extent by the spatially uniform dose errors. The positioning errors with the 1.5 cm margins used cause dose uncertainty outside the tumour volume and have a small effect on mean treatment dose (in the tumour volume) and tumour control. Copyright (2001) Australasian College of

  11. The Potential Effect of Oral Microbiota in the Prediction of Mucositis During Radiotherapy for Nasopharyngeal Carcinoma

    Directory of Open Access Journals (Sweden)

    Xiao-Xia Zhu

    2017-04-01

    Interpretation: Oral microbiota changes correlate with the progression and aggravation of radiotherapy-induced mucositis in patients with nasopharyngeal carcinoma. Microbiota-based strategies can be used for the early prediction and prevention of the incidence of severe mucositis during radiotherapy.

  12. Comparative effectiveness of radical prostatectomy and radiotherapy in prostate cancer: Observational study of mortality outcomes

    NARCIS (Netherlands)

    P. Sooriakumaran (Prasanna); T. Nyberg (Tommy); O. Akre (Olof); L. Haendler (Leif); I. Heus (Inge); M. Olsson (Marita); S. Carlsson (Sigrid); M.J. Roobol-Bouts (Monique); G. Steineck (Gunnar); P. Wiklund (Peter)

    2014-01-01

    textabstractObjective: To compare the survival outcomes of patients treated with surgery or radiotherapy for prostate cancer. Design: Observational study. Setting: Sweden, 1996-2010. Participants: 34 515 men primarily treated for prostate cancer with surgery (n=21 533) or radiotherapy (n=12 982).

  13. Effectiveness of palliative radiotherapy in patients with non-small cell lung cancer

    International Nuclear Information System (INIS)

    Chmielewska, E.; Jaskiewicz, P.

    2001-01-01

    Lung cancer is the most frequent malignant neoplasm in Poland. During the last 25 years it has become the first reason of death of men and the second of women in Poland. Patients with non-small cell lung cancer constitute 75% of all lung cancer patients. The therapy of choice for the advanced, non-small cell lung cancer is radiotherapy with palliative assumption. Many papers indicate that this therapy has no influence on long-term survival, hence it is aimed at reducing the symptoms. The therapy brings relief to 70-80% of patients. At present no other method with similar effectiveness is known. The aim of the is study was to assess the effectiveness of palliative radiotherapy as a treatment of the advanced, non-small cell lung cancel, applied as a remedy for the symptoms resulting from the growth of a lung tumour: Improvement of the quality of life and long-term survivals were assessed and prognostic factors were analysed. Between 1990 and 1995, 2330 patients with lung cancer attended the Outpatient Clinic of the Maria Sklodowska-Curie Memorial Cancer Center in Warsaw. There were 1948 patients with the non-small cell lung cancer. From this group 832 patients were qualified to palliative radiotherapy that included the primary tumour. The documentation was found for 803 patients and this group was analysed. The group constituted of 115 women (14.3%) and 688 men (85.7%), aged 28 to 91 (mean 61). In the majority of cases a significant advancement of the disease was found: stage III A in 388 patients (48.3%) and stage III B in 358 patients (44.6%). Retrospective analysis of the results of the treatment was carried out. The material contained information on 803 patients. The basis for the analysis was the survival time. It was measured from the starting date of the irradiation to the date of death or the date of the last available information that the patient lives. The survival probability was calculated with the Kaplan-Meier method. Multidimensional analysis of the

  14. P53 function influences the effect of fractionated radiotherapy on glioblastoma tumors

    International Nuclear Information System (INIS)

    Haas-Kogan, Daphne A.; Kogan, Scott S.; Yount, Garret; Hsu, Jennie; Haas, Martin; Deen, Dennis F.; Israel, Mark A.

    1999-01-01

    Purpose: Glioblastoma multiforme brain tumors (GM) are treated with a spectrum of fractionation regimens based on the clinical and anatomical characteristics of the tumor but rarely based on the molecular characteristics of the individual neoplasm. This study tests the hypothesis that the response of cell lines derived from GM to fractionated radiotherapy depends on the function of wild-type p53 (wt p53), a tumor suppressor gene frequently mutated in GM tumors. Methods and Materials: Isogenic derivatives of glioblastoma cells differing only in p53 function were prepared using a retroviral vector expressing a dominant negative mutant of p53 (mt p53). Radiation survival in vitro was quantitated using linear quadratic and repair-saturation mathematical models. Apoptosis was assayed by a terminal deoxynucleotide transferase-labeling technique and chromatin morphology. Results: We have previously reported the generation of isogenic GM cell lines differing only in p53 function. U87-175.4, lacking wt p53 function, had a significantly lower α/β value than U87-LUX.8, expressing functional wt p53, leading us to hypothesize that fractionated irradiation would preferentially spare GM cells harboring mt p53 compared with those expressing functional, wt p53. Survival curves following either 2.0 Gy or 3.5 Gy/fraction demonstrated that lack of functional wt p53 was associated with resistance to fractionated irradiation. Radiation-induced apoptosis could not account for the observed differences in clonogenic survival. Rather, our data suggested that a deficit in the G1-checkpoint contributed to increased resistance to fractionated irradiation of cells expressing mutant p53. Conclusions: The effect of fractionated radiotherapy in GM may depend on the function of the tumor suppressor gene p53. A potential clinical consequence of these findings is that hyperfractionation regimens may provide a therapeutic advantage specifically for tumors expressing wt p53 whereas a radiotherapy

  15. Selection of the optimal radiotherapy technique for locally advanced hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Lee, Ik-Jae; Seong, Jinsil; Koom, Woong-Sub; Kim, Yong-Bae; Jeon, Byeong-Chul; Kim, Joo-Ho; Han, Kwang-Hyub

    2011-01-01

    Various techniques are available for radiotherapy of hepatocellular carcinoma, including three-dimensional conformal radiotherapy, linac-based intensity-modulated radiotherapy and helical tomotherapy. The purpose of this study was to determine the optimal radiotherapy technique for hepatocellular carcinoma. Between 2006 and 2007, 12 patients underwent helical tomotherapy for locally advanced hepatocellular carcinoma. Helical tomotherapy computerized radiotherapy planning was compared with the best computerized radiotherapy planning for three-dimensional conformal radiotherapy and linac-based intensity-modulated radiotherapy for the delivery of 60 Gy in 30 fractions. Tumor coverage was assessed by conformity index, radical dose homogeneity index and moderated dose homogeneity index. Computerized radiotherapy planning was also compared according to the tumor location. Tumor coverage was shown to be significantly superior with helical tomotherapy as assessed by conformity index and moderated dose homogeneity index (P=0.002 and 0.03, respectively). Helical tomotherapy showed significantly lower irradiated liver volume at 40, 50 and 60 Gy (V40, V50 and V60, P=0.04, 0.03 and 0.01, respectively). On the contrary, the dose-volume of three-dimensional conformal radiotherapy at V20 was significantly smaller than those of linac-based intensity-modulated radiotherapy and helical tomotherapy in the remaining liver (P=0.03). Linac-based intensity-modulated radiotherapy showed better sparing of the stomach compared with helical tomotherapy in the case of separated lesions in both lobes (12.3 vs. 24.6 Gy). Helical tomotherapy showed the high dose-volume exposure to the left kidney due to helical delivery in the right lobe lesion. Helical tomotherapy achieved the best tumor coverage of the remaining normal liver. However, helical tomotherapy showed much exposure to the remaining liver at the lower dose region and left kidney. (author)

  16. Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy

    International Nuclear Information System (INIS)

    McDonald, Andrew M; Baker, Christopher B; Popple, Richard A; Shekar, Kiran; Yang, Eddy S; Jacob, Rojymon; Cardan, Rex; Kim, Robert Y; Fiveash, John B

    2014-01-01

    To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V 70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V 70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V 70 > 3 cc was associated with an increased risk of late GI events. Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients

  17. Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy.

    Science.gov (United States)

    McDonald, Andrew M; Baker, Christopher B; Popple, Richard A; Shekar, Kiran; Yang, Eddy S; Jacob, Rojymon; Cardan, Rex; Kim, Robert Y; Fiveash, John B

    2014-06-03

    To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V70 > 3 cc was associated with an increased risk of late GI events. Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients.

  18. Conventional and conformal technique of external beam radiotherapy in locally advanced cervical cancer: Dose distribution, tumor response, and side effects

    Science.gov (United States)

    Mutrikah, N.; Winarno, H.; Amalia, T.; Djakaria, M.

    2017-08-01

    The objective of this study was to compare conventional and conformal techniques of external beam radiotherapy (EBRT) in terms of the dose distribution, tumor response, and side effects in the treatment of locally advanced cervical cancer patients. A retrospective cohort study was conducted on cervical cancer patients who underwent EBRT before brachytherapy in the Radiotherapy Department of Cipto Mangunkusumo Hospital. The prescribed dose distribution, tumor response, and acute side effects of EBRT using conventional and conformal techniques were investigated. In total, 51 patients who underwent EBRT using conventional techniques (25 cases using Cobalt-60 and 26 cases using a linear accelerator (LINAC)) and 29 patients who underwent EBRT using conformal techniques were included in the study. The distribution of the prescribed dose in the target had an impact on the patient’s final response to EBRT. The complete response rate of patients to conformal techniques was significantly greater (58%) than that of patients to conventional techniques (42%). No severe acute local side effects were seen in any of the patients (Radiation Therapy Oncology Group (RTOG) grades 3-4). The distribution of the dose and volume to the gastrointestinal tract affected the proportion of mild acute side effects (RTOG grades 1-2). The urinary bladder was significantly greater using conventional techniques (Cobalt-60/LINAC) than using conformal techniques at 72% and 78% compared to 28% and 22%, respectively. The use of conformal techniques in pelvic radiation therapy is suggested in radiotherapy centers with CT simulators and 3D Radiotherapy Treatment Planning Systems (RTPSs) to decrease some uncertainties in radiotherapy planning. The use of AP/PA pelvic radiation techniques with Cobalt-60 should be limited in body thicknesses equal to or less than 18 cm. When using conformal techniques, delineation should be applied in the small bowel, as it is considered a critical organ according to RTOG

  19. Effect of integrated surgery + radiotherapy + chemotherapy treatment on survival status and serum indexes in patients with gallbladder carcinoma

    Directory of Open Access Journals (Sweden)

    Zhi-Li Wei

    2016-12-01

    Full Text Available Objective: To study the effect of integrated surgery + radiotherapy + chemotherapy treatment on the survival status and serum indexes in patients with gallbladder carcinoma. Methods: A total of 68 patients with gallbladder carcinoma were divided into observation group (received integrated surgery + radiotherapy + chemotherapy treatment and control group (received surgery + radiotherapy according to different treatments. Differences in the content of tumor markers, growth factors and adhesion molecules in serum as well as the median survival time and survival rate in 5 years of follow-up were compared between the two groups 1 month after treatment. Results: Tumor markers β2-MG, CA19-9, CA242, CA125, CA724, CEA and AFP content in serum of observation group after treatment were significantly lower than those of control group; growth factors VEGF, FGF, EGFR and HER2 content in serum were significantly lower than those of control group while IGFBP-2 and IGFBP-3 content were significantly higher than those of control group; adhesion molecules E-selectin, ICAM-1, VCAM-1 and sE-Cd content in serum were significantly lower than those of control group; the median survival time of 5-year follow-up as well as 1-, 3- and 5-year survival rate were significantly greater than those of control group. Conclusions: Integrated treatment of surgery + radiotherapy + chemotherapy can optimize the short-term and long-term curative effect in patients with gallbladder carcinoma.

  20. Development and management of severe cutaneous side effects in head-and-neck cancer patients during concurrent radiotherapy and cetuximab

    Energy Technology Data Exchange (ETDEWEB)

    Boelke, E.; Mueller-Homey, A.; Pape, H.; Giro, C.; Matuschek, C.; Gripp, S.; Budach, W. [Dept. of Radiation Oncology, Univ. of Duesseldorf (Germany); Gerber, P.A.; Bruch-Gerharz, D.; Homey, B. [Dept. of Dermatology, Univ. of Duesseldorf (Germany); Lammering, G. [Dept. of Radiation Oncology (MAASTRO Clinic), Univ. Hospital Maastricht (Netherlands); Peiper, M. [Dept. of Surgery, Univ. of Duesseldorf (Germany); Hoffmann, T.K. [Dept. of Otorhinolarynogology, Univ. of Duesseldorf (Germany)

    2008-02-15

    Background: the concurrent administration of cetuximab to radiotherapy has recently been shown to improve the clinical outcome of head-and-neck cancer (HNC) patients. An aggravation of the radiation-induced skin toxicity was not described. Here, however, two cases with severe skin toxicity during the combined treatment are reported. Clinical observations: in a small group of five patients with locally advanced HNC treated with irradiation and concurrent cetuximab, two cases of unusually severe radiation dermatitis were observed. Both patients developed confluent moist desquamations confined to the irradiation field at a dose of 40 Gy (CTC - Common Toxicity Criteria, grade 3), which progressed into an ulcerative dermatitis (grade 4) at 58 Gy and 46 Gy, respectively. Histopathology showed a vacuolic degeneration of basal keratinocytes, subepidermal blister formation, and mixed perivascular and interstitial inflammatory infiltrates leading to a complete loss of the epidermis. These cutaneous side effects led to the discontinuation of radiotherapy. Topical corticosteroids and systemic antibiotic treatment resulted in wound healing, which allowed the continuation of radiotherapy. Conclusion: these findings indicate that cetuximab may have the potential to enhance the severity of radiation dermatitis in HNC patients. A systematic monitoring of cutaneous side effects during radiotherapy plus cetuximab is advised in order to reliably estimate the frequency of severe (grade 3/4) radiation dermatitis. (orig.)

  1. Development and management of severe cutaneous side effects in head-and-neck cancer patients during concurrent radiotherapy and cetuximab

    International Nuclear Information System (INIS)

    Boelke, E.; Mueller-Homey, A.; Pape, H.; Giro, C.; Matuschek, C.; Gripp, S.; Budach, W.; Gerber, P.A.; Bruch-Gerharz, D.; Homey, B.; Lammering, G.; Peiper, M.; Hoffmann, T.K.

    2008-01-01

    Background: the concurrent administration of cetuximab to radiotherapy has recently been shown to improve the clinical outcome of head-and-neck cancer (HNC) patients. An aggravation of the radiation-induced skin toxicity was not described. Here, however, two cases with severe skin toxicity during the combined treatment are reported. Clinical observations: in a small group of five patients with locally advanced HNC treated with irradiation and concurrent cetuximab, two cases of unusually severe radiation dermatitis were observed. Both patients developed confluent moist desquamations confined to the irradiation field at a dose of 40 Gy (CTC - Common Toxicity Criteria, grade 3), which progressed into an ulcerative dermatitis (grade 4) at 58 Gy and 46 Gy, respectively. Histopathology showed a vacuolic degeneration of basal keratinocytes, subepidermal blister formation, and mixed perivascular and interstitial inflammatory infiltrates leading to a complete loss of the epidermis. These cutaneous side effects led to the discontinuation of radiotherapy. Topical corticosteroids and systemic antibiotic treatment resulted in wound healing, which allowed the continuation of radiotherapy. Conclusion: these findings indicate that cetuximab may have the potential to enhance the severity of radiation dermatitis in HNC patients. A systematic monitoring of cutaneous side effects during radiotherapy plus cetuximab is advised in order to reliably estimate the frequency of severe (grade 3/4) radiation dermatitis. (orig.)

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  3. Effective local control of vertebral metastases by simultaneous integrated boost radiotherapy. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Lubgan, Dorota; Ziegaus, Anke; Semrau, Sabine; Lambrecht, Ulrike; Lettmaier, Sebastian; Fietkau, Rainer [Erlangen University Hospital, Department of Radiation Oncology, Erlangen (Germany)

    2014-11-14

    The primary endpoint was to improve local tumour control of patients with metastatic spinal tumours by stereotactic body radiotherapy (SBRT) and dose escalation by simultaneous, integrated boost (PTV-boost). We used a whole vertebral body (PTV-elective) contouring approach. Secondary endpoints were severity of acute and chronic adverse effects and overall survival. In all, 33 patients with metastases of the vertebral column were treated at Erlangen University Hospital. SBRT was given in 12 or 10 fractions. The metastatic lesion (PTV-boost) received 3.6 Gy (range 3.0-4.51 Gy) per fraction for a total of 42.0 Gy (24.36-48.0 Gy) and the whole vertebra (PTV-elective) received 2.85 Gy (range 1.8-3.6 Gy) per fraction for a total of 32.39 Gy (range 21.60-38.0 Gy). Patients were followed up every 3 months. Local control rate of all patients was 93 % at 12 and 24 months. The overall survival rate was 54 % at 12 months, 38 % at 24 months and 18 % at 36 months. No radiation myelopathy occurred. The most frequently observed adverse events in 3 cases was oesophagitis grade 2. SBRT with simultaneous, integrated boost was associated with excellent local control of 93 % after 24 months. This result shows the possibility of delivering escalated doses to the target while still keeping the incidence of side effects low. This study forms the basis for a future randomised controlled trial comparing conventional radiotherapy (10 fractions of 3 Gy) with hypofractionated dose intensified SBRT (12 fractions of 3 Gy + integrated boost 12 fractions of 4 Gy) for improvement of local tumour control and pain. (orig.) [German] Das primaere Ziel der Studie war die Verbesserung der lokalen Tumorkontrolle von Patienten mit Wirbelkoerpermetastasen mittels stereotaktischer Radiotherapie (SBRT) mit Dosiseskalation durch einen simultan integrierten Boost (PTV-Boost). Dabei wurde der ganze Wirbelkoerper konturiert (PTV-Elektive). Zu den sekundaeren Endpunkten der Studie gehoerten der Schweregrad von

  4. Whither radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ross, W M

    1987-03-01

    The 1986 Glyn Evans Memorial Lecture, given at the Joint Provincial Meeting of the Royal College of Radiologists, Sheffield, September 1986, sketches an outline of the history of radiotherapy and discusses the future development of the art. Topics included are siting of centres, training needs, the relationship of radiotherapy to other medical specialities, and the advantages and disadvantages of radiotherapy practitioners forming a separate medical College. (U.K.)

  5. Cost-effectiveness of preoperative radiotherapy in rectal cancer: results from the Swedish Rectal Cancer Trial

    International Nuclear Information System (INIS)

    Dahlberg, Michael; Stenborg, Anna; Paahlman, Lars; Glimelius, Bengt

    2002-01-01

    Purpose: The Swedish Rectal Cancer Trial (SRCT) demonstrated that a short-term regimen of high-dose fractionated preoperative radiotherapy (5 x 5 Gy) reduced the local recurrence rates and improved overall survival. This has had an impact on the primary treatment of rectal cancer. The current study investigated the cost-effectiveness of the new combined approach. Methods and Materials: After an 8-year follow-up, in-hospital and outpatient costs related to the treatment of rectal cancer and its complications were analyzed for 98 randomly allocated patients who participated in the SRCT from a single Swedish health care region. The costs were then related to the clinical data from the SRCT regarding complications, local and distant recurrences, and survival. Results: The total cost for a nonirradiated patient was US$30,080 compared with US$35,268 for an irradiated patient. The surgery-alone group had increased costs related to local recurrences, and the radiotherapy group had increased costs for irradiation and complications. With a survival benefit of 21 months (retrieved from the SRCT), the cost for a saved year was US$3654. Sensitivity analyses for different rates of local recurrences, the costs related to complications and less marked survival benefit showed that this figure could vary up to US$15,228. Conclusion: The cost for a life-year saved in these data was US$3654. This figure could reach US$15,228 in the most pessimistic setting of the sensitivity tests, a cost still comparable with other well-accepted medical interventions

  6. Priming the Abscopal Effect Using Multifunctional Smart Radiotherapy Biomaterials Loaded with Immunoadjuvants

    Directory of Open Access Journals (Sweden)

    Michele Moreau

    2018-03-01

    Full Text Available In this study, we investigate the use of multifunctional smart radiotherapy biomaterials (SRBs loaded with immunoadjuvants for boosting the abscopal effect of local radiotherapy (RT. SRBs were designed similar to currently used inert RT biomaterials, incorporating a biodegradable polymer with reservoir for loading payloads of the immunoadjuvant anti-CD40 monoclonal antibody. Lung (LLC1 tumors were generated both on the right and left flank of each mouse, with the left tumor representing metastasis. The mice were randomized and divided into eight cohorts with four cohorts receiving image-guided RT (IGRT at 5 Gy and another similar four cohorts at 0 Gy. IGRT and Computed Tomography (CT imaging were performed using a small animal radiation research platform (SARRP. Tumor volume measurements for both flank tumors and animal survival was assessed over 25 weeks. Tumor volume measurements showed significantly enhanced inhibition in growth for the right flank tumors of mice in the cohort treated with SRBs loaded with CD40 mAbs and IGRT. Results also suggest that the use of polymeric SRBs with CD40 mAbs without RT could generate an immune response, consistent with previous studies showing such response when using anti-CD40. Overall, 60% of mice treated with SRBs showed complete tumor regression during the observation period, compared to 10% for cohorts administered with anti-CD40 mAbs, but no SRB. Complete tumor regression was not observed in any other cohorts. The findings justify more studies varying RT doses and quantifying the immune-cell populations involved when using SRBs. Such SRBs could be developed to replace currently used RT biomaterials, allowing not only for geometric accuracy during RT, but also for extending RT to the treatment of metastatic lesions.

  7. Study of the heterogeneity effects of lung in the evaluation of absorbed dose in radiotherapy

    International Nuclear Information System (INIS)

    Campos, Luciana Tourinho

    2006-02-01

    The main objective of radiotherapy is to deliver the highest possible dose to the tumour, in order to destroy it, reducing as much as possible the doses to healthy tissues adjacent to the target volume. Therefore, it is necessary to do a planning of the treatment. The more complex is the treatment, the more difficult the planning will be, demanding computation sophisticated methods in its execution, in order to consider the heterogeneities present in the human body. Additionally, with the appearing of new radiotherapeutic techniques, that used irradiation fields of small area, for instance, the intensity modulated radiotherapy, the difficulties for the execution of a reliable treatment planning, became still larger. In this work it was studied the influence of the lung heterogeneity in the planning of the curves of percentage depth dose, PDP, obtained with the Eclipse R planning system for different sizes of irradiation fields, using the correction algorithms for heterogeneities available in the planning system: modified Batho, general Batho and equivalent tissue-air ratio. A thorax phantom, manufactured in acrylic, containing a region made of cork to simulate the lung tissue, was used. The PDP curves generated by the planning system were compared to those obtained by Monte Carlo simulation and with the use of thermoluminescent, TL, dosimetry. It was verified that the algorithms used by the Eclipse R system for the correction of heterogeneity effects are not able to generate correct results for PDP curves in the case of small fields, occurring differences of up to 100%, when the 1x1 cm 2 treatment field is considered. These differences can cause a considerable subdosage in the lung tissue, reducing the possibility of the patient cure. (author)

  8. Antitumor Effects of Palladium-α-Lipoic Acid Complex Formulation as an Adjunct in Radiotherapy.

    Science.gov (United States)

    Veena, Ravindran Kalathil; Ajith, Thekkuttuparambil Ananthanarayanan; Janardhanan, Kainoor Krishnankutty; Antonawich, Francis

    2016-01-01

    Several investigations have been initiated to enhance the antitumor effect of radiation and ameliorate its adverse effects such as reducing blood cell counts and causing DNA damage in normal cells. Compounds that enhance the antitumor activity of radiation without reducing blood cell counts or damaging DNA in normal cells can be of immense use as an adjunct in radiotherapy. We evaluated the antitumor effect of a specific set of minerals, vitamins, and amino acids (Poly-MVA) (2 mL/kg, per os), with and without radiation, against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines that were transplanted in a solid-tumor model. Whole-body γ-radiation exposure (2 Gy) was performed using 60Co. Poly-MVA enhanced the antitumor effect of radiation when administered beforehand. Furthermore, Poly-MVA administered once daily for 2 wk, immediately after 4 Gy irradiation, protected DNA damage in peripheral blood. It also rendered protection against the radiation-induced reduction of platelet count. The unique electronic and redox properties of palladium-α-lipoic acid complex in Poly-MVA appear to be responsible for the exhibited effect. The results conclude that the antitumor-enhancing and normal cell-protective effect of Poly-MVA warrants additional studies for its potential clinical application.

  9. The clinical implementation of respiratory-gated intensity-modulated radiotherapy

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  10. Factors Influencing Neurocognitive Outcomes in Young Patients With Benign and Low-Grade Brain Tumors Treated With Stereotactic Conformal Radiotherapy

    International Nuclear Information System (INIS)

    Jalali, Rakesh; Mallick, Indranil; Dutta, Debnarayan

    2010-01-01

    Purpose: To present the effect of radiotherapy doses to different volumes of normal structures on neurocognitive outcomes in young patients with benign and low-grade brain tumors treated prospectively with stereotactic conformal radiotherapy (SCRT). Methods and Materials: Twenty-eight patients (median age, 13 years) with residual/progressive brain tumors (10 craniopharyngioma, 8 cerebellar astrocytoma, 6 optic pathway glioma and 4 cerebral low-grade glioma) were treated with SCRT to a dose of 54 Gy in 30 fractions over 6 weeks. Prospective neuropsychological assessments were done at baseline before RT and at subsequent follow-up examinations. The change in intelligence quotient (IQ) scores was correlated with various factors, including dose-volume to normal structures. Results: Although the overall mean full-scale IQ (FSIQ) at baseline before RT remained unchanged at 2-year follow-up after SCRT, one third of patients did show a >10% decline in FSIQ as compared with baseline. Logistic regression analysis demonstrated that patients aged 10% drop in FSIQ than older patients (53% vs. 10%, p = 0.03). Dosimetric comparison in patients showing a >10% decline vs. patients showing a 43.2 Gy to >13% of volume of the left temporal lobe were the ones to show a significant drop in FSIQ (p = 0.048). Radiotherapy doses to other normal structures, including supratentorial brain, right temporal lobe, and frontal lobes, did not reveal any significant correlation. Conclusion: Our prospectively collected dosimetric data show younger age and radiotherapy doses to left temporal lobe to be predictors of neurocognitive decline, and may well be used as possible dose constraints for high-precision radiotherapy planning.

  11. Study of the effect of misonidazole in conjunction with radiotherapy for the treatment of head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Henk, J.M.; Adams, G.E.; Ash, D. (Medical Research Council, London (UK))

    1984-07-01

    The effect of the hypoxic cell sensitiser misonidazole as an adjuvant to radiotherapy of head and neck cancer was tested in a randomised double blind study. Patients with squamous carcinoma of the upper alimentary and respiratory tract, excluding those with early disease with good prognosis, who were deemed suitable for radical radiotherapy and fit to receive the drug were entered. Two radiotherapy regimes were employed, 10 fractions in 3 weeks to a modal tumour dose of 4000-4500 cGy, and 20 fractions in 4 weeks to a modal tumour dose of 5000-5750 cGy. Participating radiotherapists opted for one of the schemes. Misonidazole or placebo capsules were administered 4 to 5 hours before each fraction of radiotherapy to a total of 11 to 13 g/m/sup 2/. 168 patients were treated with 10 fractions and 99 with 20 fractions, between March 1979 and November 1981, when entry was stopped because of the high incidence of drug toxicity and lack of benefit. The estimated hazard ratio for local control was 0.89, indicating a slight advantage to misonidazole, statistically insignificant (p = 0.5). Peripheral neuropathy occurred in 56 patients receiving misonidazole, and was more severe when treatment was given in 10 fractions.

  12. Effect of fractionated regional external beam radiotherapy on peripheral blood cell count

    International Nuclear Information System (INIS)

    Zachariah, B.; Jacob, S.S.; Gwede, C.; Cantor, A.; Patil, J.; Casey, L.; Zachariah, A.B.

    2001-01-01

    Purpose: The purpose of this study was to assess the need for obtaining weekly complete blood count (CBC) values and to identify the pattern of changes in CBC during regional conventional fractionated radiotherapy. Methods and Materials: A retrospective analysis of CBC data on 299 adult cancer patients who received definitive conventional radiotherapy to head and neck (n=95), chest (n=96), and pelvis (n=108) was performed. Temporal patterns and magnitude of change in white blood cells, neutrophils, lymphocytes, and platelets during radiotherapy were examined. Results: There were statistically significant declines in all counts, albeit not clinically significant. Notable differences between disease sites were found. The greatest weekly interval change in counts occurred during the first week of radiotherapy for all groups of patients. The mean WBC nadir values during treatment were 5.8 for head and neck, 6.8 for chest, and 5.4 for pelvis. The nadirs for all counts occurred toward the middle-to-end of radiotherapy. Lymphocytes were found to be more sensitive to radiotherapy than other leukocyte subcomponents. Conclusion: Our study suggests that weekly CBC monitoring is not necessary for all patients undergoing standard fractionated radiotherapy. Baseline blood counts may be used to determine an optimal schedule for monitoring CBCs in patients receiving conventional radiation alone. Reduced monitoring of CBC may result in significant financial savings

  13. Effect of Whole Pelvic Radiotherapy for Patients With Locally Advanced Prostate Cancer Treated With Radiotherapy and Long-Term Androgen Deprivation Therapy

    International Nuclear Information System (INIS)

    Mantini, Giovanna; Tagliaferri, Luca; Mattiucci, Gian Carlo; Balducci, Mario; Frascino, Vincenzo; Dinapoli, Nicola; Di Gesù, Cinzia; Ippolito, Edy; Morganti, Alessio G.; Cellini, Numa

    2011-01-01

    Purpose: To evaluate the effect of whole pelvic radiotherapy (WPRT) in prostate cancer patients treated with RT and long-term (>1 year) androgen deprivation therapy (ADT). Methods and materials: Prostate cancer patients with high-risk features (Stage T3-T4 and/or Gleason score ≥7 and/or prostate-specific antigen level ≥20 ng/mL) who had undergone RT and long-term ADT were included in the present analysis. Patients with bowel inflammatory disease, colon diverticula, and colon diverticulitis were excluded from WPRT and treated with prostate-only radiotherapy (PORT). Patients were grouped according to nodal risk involvement as assessed by the Roach formula using different cutoff levels (15%, 20%, 25%, and 30%). Biochemical disease-free survival (bDFS) was analyzed in each group according to the RT type (WPRT or PORT). Results: A total of 358 patients treated between 1994 and 2007 were included in the analysis (46.9% with WPRT and 53.1% with PORT). The median duration of ADT was 24 months (range, 12–38). With a median follow-up of 52 months (range, 20–150), the overall 4-year bDFS rate was 90.5%. The 4-year bDFS rate was similar between the patients who had undergone WPRT or PORT (90.4% vs. 90.5%; p = NS). However, in the group of patients with the greatest nodal risk (>30%), a significant bDFS improvement was recorded for the patients who had undergone WPRT (p = .03). No differences were seen in acute toxicity among the patients treated with WPRT or PORT. The late gastrointestinal toxicity was similar in patients treated with PORT or WPRT (p = NS). Conclusions: Our analysis has supported the use of WPRT in association with long-term ADT for patients with high-risk nodal involvement (>30%), although a definitive recommendation should be confirmed by a randomized trial.

  14. Radiotherapy and oral cancer

    Energy Technology Data Exchange (ETDEWEB)

    Sealy, R [Cape Town Univ. (South Africa). Dept. of Radiotherapy

    1982-08-01

    A general review article for the non-radiotherapist. The historical, physical and biological background is briefly reviewed. Mention is made of the effects of fraction size, hyperbaric oxygen, neutron beams and radiation sensitizers. The use of chemotherapy and radiotherapy is discussed, as well as the selection of patients for radiotherapy and the treatment of neck nodes. The author suggests a therapeutic approach to the various disease sites and finally reviews some of the literature on radiation caries and jaw necrosis.

  15. Osteoradionecrosis following treatment for head and neck cancer and the effect of radiotherapy dosimetry: the Guy's and St Thomas' Head and Neck Cancer Unit experience.

    Science.gov (United States)

    De Felice, Francesca; Thomas, Christopher; Patel, Vinod; Connor, Steve; Michaelidou, Andriana; Sproat, Chris; Kwok, Jerry; Burke, Mary; Reilly, Damien; McGurk, Mark; Simo, Ricard; Lyons, Andrew; Oakley, Richard; Jeannon, Jean-Pierre; Lei, Mary; Urbano, Teresa Guerrero

    2016-07-01

    To analyze clinical features, dosimetric parameters, and outcomes of osteoradionecrosis (ORN). Thirty-six patients with ORN who had been previously treated with radiotherapy (RT) were retrospectively identified between January 2009 and April 2014. ORN volumes were contoured on planning computed tomography (CT) scans. Near maximum dose (D2%), minimum dose (Dmin), mean dose (Dmean), and percentage of bone volume receiving 50 Gy (V50) were examined. Clinical and dosimetric variables were considered to compare ORN resolution versus ORN persistence. Median interval time from end of RT to development of ORN was 6 months. Of the ORN cases, 61% were located in the mandible. Dmean to affected bone was 57.6 Gy, and 44% had a D2% 65 Gy or greater. Smoking was associated with ORN persistence on univariate analysis, but no factors were found to impact ORN resolution or progression on logistic regression. Prevention strategies for ORN development should be prioritized. Dose-volume parameters could have a role in preventing ORN. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Perturbation effects of the carbon fiber-PEEK screws on radiotherapy dose distribution.

    Science.gov (United States)

    Nevelsky, Alexander; Borzov, Egor; Daniel, Shahar; Bar-Deroma, Raquel

    2017-03-01

    Radiation therapy, in conjunction with surgical implant fixation, is a common combined treatment in cases of bone metastases. However, metal implants generally used in orthopedic implants perturb radiation dose distributions. Carbon-Fiber Reinforced Polyetheretherketone (CFR-PEEK) material has been recently introduced for production of intramedullary nails and plates. The purpose of this work was to investigate the perturbation effects of the new CFR-PEEK screws on radiotherapy dose distributions and to evaluate these effects in comparison with traditional titanium screws. The investigation was performed by means of Monte Carlo (MC) simulations for a 6 MV photon beam. The project consisted of two main stages. First, a comparison of measured and MC calculated doses was performed to verify the validity of the MC simulation results for different materials. For this purpose, stainless steel, titanium, and CFR-PEEK plates of various thicknesses were used for attenuation and backscatter measurements in a solid water phantom. For the same setup, MC dose calculations were performed. Next, MC dose calculations for titanium, CFR-PEEK screws, and CFR-PEEK screws with ultrathin titanium coating were performed. For the plates, the results of our MC calculations for all materials were found to be in good agreement with the measurements. This indicates that the MC model can be used for calculation of dose perturbation effects caused by the screws. For the CFR-PEEK screws, the maximum dose perturbation was less than 5%, compared to more than 30% perturbation for the titanium screws. Ultrathin titanium coating had a negligible effect on the dose distribution. CFR-PEEK implants have good prospects for use in radiotherapy because of minimal dose alteration and the potential for more accurate treatment planning. This could favorably influence treatment efficiency and decrease possible over- and underdose of adjacent tissues. The use of such implants has potential clinical advantages

  17. Synergistic Effects of NDRG2 Overexpression and Radiotherapy on Cell Death of Human Prostate LNCaP Cells.

    Science.gov (United States)

    Alizadeh Zarei, M; Takhshid, M A; Behzad Behbahani, A; Hosseini, S Y; Okhovat, M A; Rafiee Dehbidi, Gh R; Mosleh Shirazi, M A

    2017-09-01

    Radiation therapy is among the most conventional cancer therapeutic modalities with effective local tumor control. However, due to the development of radio-resistance, tumor recurrence and metastasis often occur following radiation therapy. In recent years, combination of radiotherapy and gene therapy has been suggested to overcome this problem. The aim of the current study was to explore the potential synergistic effects of N-Myc Downstream-Regulated Gene 2 (NDRG2) overexpression, a newly identified candidate tumor suppressor gene, with radiotherapy against proliferation of prostate LNCaP cell line. In this study, LNCaP cells were exposed to X-ray radiation in the presence or absence of NDRG2 overexpression using plasmid PSES- pAdenoVator-PSA-NDRG2-IRES-GFP. The effects of NDRG2 overexpression, X-ray radiation or combination of both on the cell proliferation and apoptosis of LNCaP cells were then analyzed using MTT assay and flow cytometery, respectively. Results of MTT assay showed that NDRG2 overexpression and X-ray radiation had a synergistic effect against proliferation of LNCaP cells. Moreover, NDRG2 overexpression increased apoptotic effect of X-ray radiation in LNCaP cells synergistically. Our findings suggested that NDRG2 overexpression in combination with radiotherapy may be an effective therapeutic option against prostate cancer.

  18. Palliative radiotherapy for liver metastases

    International Nuclear Information System (INIS)

    Eble, M.J.; Gademann, G.; Wannenmacher, M.

    1993-01-01

    The role of palliative irradiation was analysed in 55 patients with liver metastases from colorectal, breast and lung cancer, treated with irradiation doses more than 10 Gy. In 47 patients irradiation alone was done. In 29 patients the disease involved not only the liver, but was disseminated. A mean dose of 23.8 Gy was delivered, with daily fractions of 1.5, 1.8 or 2 Gy. Complete and near complete pain relief was obtained in six and nine patients. Normalized and near normalized values of bilirubin serum levels were obtained in five and seven patients. Relief of pain as well as normalisation of cholestasis were significantly correlated with the irradiation doses applied. Median survival was 36.5 days for patients with lung cancer, 70.5 and 73 days for patients with breast and colorectal cancer. Irradiation doses given and the status of disease were significantly correlated to prognosis. In the majority of our patients with clinical symptoms, i.e. pain or cholestase, irradiation alone was sufficient for palliation of these symptoms. Prognosis is limited because of the disseminated state of disease in 62% of the patients. In a group of patients, suffering from colorectal cancer with good prognostic criteria, the simultaneous application of radiotherapy and systemic chemotherapy was able to increase significantly the survival with minor toxicity. The use of a three-dimensional treatment planning could optimize the radiotherapy, due to the dose-volume histogram analysis. (orig./MG) [de

  19. High biologically effective dose radiation therapy using brachytherapy in combination with external beam radiotherapy for high-risk prostate cancer

    Directory of Open Access Journals (Sweden)

    Keisei Okamoto

    2017-02-01

    Full Text Available Purpose : To evaluate the outcomes of high-risk prostate cancer patients treated with biologically effective dose (BED ≥ 220 Gy of high-dose radiotherapy, using low-dose-rate (LDR brachytherapy in combination with external beam radiotherapy (EBRT and short-term androgen deprivation therapy (ADT. Material and methods : From 2005 to 2013, a total of 143 patients with high-risk prostate cancer were treated by radiotherapy of BED ≥ 220 Gy with a combination of LDR brachytherapy, EBRT, and androgen deprivation therapy (ADT. The high-risk patients in the present study included both high-risk and very high-risk prostate cancer. The number of high-risk features were: 60 patients with 1 high-risk factor (42%, 61 patients with 2 high-risk factors (43%, and 22 patients with 3 high-risk factors (15% including five N1 disease. External beam radiotherapy fields included prostate and seminal vesicles only or whole pelvis depending on the extension of the disease. Biochemical failure was defined by the Phoenix definition. Results : Six patients developed biochemical failure, thus providing a 5-year actual biochemical failure-free survival (BFFS rate of 95.2%. Biochemical failure was observed exclusively in cases with distant metastasis in the present study. All six patients with biochemical relapse had clinical failure due to bone metastasis, thus yielding a 5-year freedom from clinical failure (FFCF rate of 93.0%. None of the cases with N1 disease experienced biochemical failure. We observed four deaths, including one death from prostate cancer, therefore yielding a cause-specific survival (CSS rate of 97.2%, and an overall survival (OS rate of 95.5%. Conclusions : High-dose (BED ≥ 220 Gy radiotherapy by LDR in combination with EBRT has shown an excellent outcome on BFFS in high-risk and very high-risk cancer, although causal relationship between BED and BFFS remain to be explained further.

  20. DEGRO practical guidelines: radiotherapy of breast cancer II. Radiotherapy of non-invasive neoplasia of the breast

    International Nuclear Information System (INIS)

    Souchon, R.; Sautter-Bihl, M.L.; Sedlmayer, F.; Budach, W.; Dunst, J.; Feyer, P.; Fietkau, R.; Sauer, R.; Harms, W.; Wenz, F.; Haase, W.

    2014-01-01

    reduces recurrence risks of ipsilateral DCIS as well as invasive breast cancer independent of patient age in all subgroups. The recommended total dose is 50 Gy administered as whole breast irradiation (WBI) in single fractions of 1.8 or 2.0 Gy given on 5 days weekly. Retrospective data indicate a possible beneficial effect of an additional tumor bed boost for younger patients. Prospective clinical trials of different dose-volume concepts (hypofractionation, accelerated partial breast irradiation, boost radiotherapy) are still ongoing. Postoperative radiotherapy permits breast conservation for the majority of women by halving local recurrence as well as reducing progression rates into invasive cancer. New data confirmed this effect in all patient subsets - even in low risk subgroups (LoE 1a). (orig.) [de

  1. Clinical effects of CG (Hythiol) tablets on leukopenia resulting from radiotherapy

    International Nuclear Information System (INIS)

    Fukui, Hideki; Sakaguchi, Kokichi; Sekiba, Kaoru

    1984-01-01

    A double-blind comparative study of CG(L-cysteine) tablets and approved drugs (CG capsules) was made to assess clinical effects of CG tablets on leukopenia. The subjects were 75 patients with cancer of the uterine cervix in whom the number of WBC was 4,500-7,500/mm before irradiation. The ratios of patients who kept WBC as 3,500/mm or more were 64.7% in the group with CG tablets and 50% in the group with CG capsules with no statistical significance. The ratios of patients who kept WBC as 3,000/mm or more were 82.4% in the group with CG tablets and 79.4% in the group with CG capsules with no statistical significance. The ratios to prevent leukopenia were 70.6% in the group with CG tablets and 58.8% in the group with CG capsules with no significant difference. Other hematological findings, subjective symptoms and the performance of radiotherapeutic protocol were not different between the groups. No marked side effects were observed. These results suggest that CG tablets, as well as CG capsules, are effective for preventing leukopenia resulting from radiotherapy. (Namekawa, K.)

  2. Transcutaneous carbon dioxide enhances the antitumor effect of radiotherapy on oral squamous cell carcinoma.

    Science.gov (United States)

    Iwata, Eiji; Hasegawa, Takumi; Ueha, Takeshi; Takeda, Daisuke; Saito, Izumi; Kawamoto, Teruya; Akisue, Toshihiro; Sakai, Yoshitada; Sasaki, Ryohei; Kuroda, Ryosuke; Komori, Takahide

    2018-05-16

    Radiotherapy (RT) is one of the main treatment modalities for oral squamous cell carcinoma (OSCC), however, radioresistance is a major impediment to its clinical success and poses as a concern that needs to be addressed. Tumor hypoxia is known to be significantly associated with radioresistance in various malignancies, hence, resolving the hypoxic state of a tumor may improve the antitumor effect of RT on OSCC. We have previously revealed that transcutaneous CO2 induced mitochondrial apoptosis and suppressed tumor growth in OSCC by resolving hypoxia. Considering the previous study, we hypothesized that transcutaneous CO2 may enhance the antitumor effect of RT on OSCC by improving intratumoral hypoxia, thereby overcoming radioresistance. In the present study, the combination of transcutaneous CO2 and RT significantly inhibited tumor growth compared with other treatments. This combination therapy also led to decreased expression of HIF-1α in parallel with increased expression of the cleaved forms of caspase-3-8-9 and PARP, which play essential roles in mitochondrial apoptosis. Additionally, the combination therapy increased the expression of ROS modulator 1 and subsequent mitochondrial ROS production, compared to RT alone. These results indicated that transcutaneous CO2 could potentially improve the antitumor effect of RT by decreasing the intratumoral hypoxia and increasing the mitochondrial apoptosis. Our findings indicated that CO2 therapy may be a novel adjuvant therapy in combination with RT for OSCC.

  3. Gold namoprtices enhance anti-tumor effect of radiotherapy to hypoxic tumor

    International Nuclear Information System (INIS)

    Kim, Mi Sun; Lee, Eun Jung; Kim, Jae Won; Keum, Ki Chang; Koom, Woong Sub; Chung, Ui Seok; Koh, Won Gun

    2016-01-01

    Hypoxia can impair the therapeutic efficacy of radiotherapy (RT). Therefore, a new strategy is necessary for enhancing the response to RT. In this study, we investigated whether the combination of nanoparticles and RT is effective in eliminating the radioresistance of hypoxic tumors. Gold nanoparticles (GNPs) consisting of a silica core with a gold shell were used. CT26 colon cancer mouse model was developed to study whether the combination of RT and GNPs reduced hypoxia-induced radioresistance. Hypoxia inducible factor-1α (HIF-1α) was used as a hypoxia marker. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were conducted to evaluate cell death. Hypoxic tumor cells had an impaired response to RT. GNPs combined with RT enhanced anti-tumor effect in hypoxic tumor compared with RT alone. The combination of GNPs and RT decreased tumor cell viability compare to RT alone in vitro. Under hypoxia, tumors treated with GNPs + RT showed a higher response than that shown by tumors treated with RT alone. When a reactive oxygen species (ROS) scavenger was added, the enhanced antitumor effect of GNPs + RT was diminished. In the present study, hypoxic tumors treated with GNPs + RT showed favorable responses, which might be attributable to the ROS production induced by GNPs + RT. Taken together, GNPs combined with RT seems to be potential modality for enhancing the response to RT in hypoxic tumors

  4. Effectiveness of gene expression profiling for response prediction of rectal cancer to preoperative radiotherapy

    International Nuclear Information System (INIS)

    Ojima, Eiki; Inoue, Yasuhiro; Miki, Chikao; Kusunoki, Masato; Mori, Masaki

    2007-01-01

    Our aim was to determine whether the expression levels of specific genes could predict clinical radiosensitivity in human colorectal cancer. Radioresistant colorectal cancer cell lines were established by repeated X-ray exposure (total, 100 Gy), and the gene expressions of the parent and radioresistant cell lines were compared in a microarray analysis. To verify the microarray data, we carried out a reverse transcriptase-polymerase chain reaction analysis of identified genes in clinical samples from 30 irradiated rectal cancer patients. A comparison of the intensity data for the parent and three radioresistant cell lines revealed 17 upregulated and 142 downregulated genes in all radioresistant cell lines. Next, we focused on two upregulated genes, PTMA (prothymosin α) and EIF5a2 (eukaryotic translation initiation factor 5A), in the radioresistant cell lines. In clinical samples, the expression of PTMA was significantly higher in the minor effect group than in the major effect group (P=0.004), but there were no significant differences in EIF5a2 expression between the two groups. We identified radiation-related genes in colorectal cancer and demonstrated that PTMA may play an important role in radiosensitivity. Our findings suggest that PTMA may be a novel marker for predicting the effectiveness of radiotherapy in clinical cases. (author)

  5. Gold namoprtices enhance anti-tumor effect of radiotherapy to hypoxic tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Sun; Lee, Eun Jung; Kim, Jae Won; Keum, Ki Chang; Koom, Woong Sub [Dept. of Radiation Oncology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Chung, Ui Seok; Koh, Won Gun [Dept. of Chemical and Biomolecular Engineering, Yonsei University, Seoul (Korea, Republic of)

    2016-09-15

    Hypoxia can impair the therapeutic efficacy of radiotherapy (RT). Therefore, a new strategy is necessary for enhancing the response to RT. In this study, we investigated whether the combination of nanoparticles and RT is effective in eliminating the radioresistance of hypoxic tumors. Gold nanoparticles (GNPs) consisting of a silica core with a gold shell were used. CT26 colon cancer mouse model was developed to study whether the combination of RT and GNPs reduced hypoxia-induced radioresistance. Hypoxia inducible factor-1α (HIF-1α) was used as a hypoxia marker. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were conducted to evaluate cell death. Hypoxic tumor cells had an impaired response to RT. GNPs combined with RT enhanced anti-tumor effect in hypoxic tumor compared with RT alone. The combination of GNPs and RT decreased tumor cell viability compare to RT alone in vitro. Under hypoxia, tumors treated with GNPs + RT showed a higher response than that shown by tumors treated with RT alone. When a reactive oxygen species (ROS) scavenger was added, the enhanced antitumor effect of GNPs + RT was diminished. In the present study, hypoxic tumors treated with GNPs + RT showed favorable responses, which might be attributable to the ROS production induced by GNPs + RT. Taken together, GNPs combined with RT seems to be potential modality for enhancing the response to RT in hypoxic tumors.

  6. Role of ACNU-induced cell cycle perturbations in enhancing effect on radiotherapy

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    Murakami, Naoto (Niigata Univ. (Japan). Brain Research Inst.)

    1992-05-01

    The cell cycle perturbations induced by ACNU and their role in enhancing effect on radiotherapy were studied using C[sub 6] rat glioma cells. The cell cycle perturbations were analyzed with flow cytometry from 3 to 72 hours after ACNU treatment. The major effect of ACNU on cell cycle progression was G[sub 2]M accumulation. Alteration of the DNA histograms after exposure to ACNU (10, 25 [mu]g/ml) showed common features; the G[sub 2]M accumulation increased to a maximum at 24 hr, remained by 30 hr, then decreased gradually. From these analyses, the temporal course of accumulation to G[sub 2]M phase of cell cycle in the presence of ACNU (10, 25 [mu]g/ml) was demonstrated. To examine whether the G[sub 2]M accumulation induced by ACNU is responsible for the potentiation of irradiation, the following study was performed. Cells were irradiated (6 Gy) at various time intervals after ACNU treatment (25 [mu]g/ml, 1 hr), and posttreatment survival was assessed by colony forming assay. All survival values obtained from the combination treatment schedules were normalized for the ACNU cell kill and then compared with the survival value obtained after irradiation alone. It appeared that combined treatment had a similar synergistic effect in all combination schedules. From these studies, it was concluded that the G[sub 2]M accumulation induced by ACNU would not be the partial synchronization as the mechanism responsible for the potentiation of irradiation. (author).

  7. Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship

    Energy Technology Data Exchange (ETDEWEB)

    Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake,