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Radiation therapy plays an important role in the multidisciplinary management of breast cancer. Recent years have seen improvements in breast cancer survival and a greater appreciation of potential long-term morbidity associated with the dose and volume of irradiated organs. Proton therapy reduces the dose to nontarget structures while optimizing target coverage. However, there remain additional financial costs associated with proton therapy, despite reductions over time, and studies have yet to demonstrate that protons improve upon the treatment outcomes achieved with photon radiation therapy. There remains considerable heterogeneity in proton patient selection and techniques, and the rapid technological advances in the field have the potential to affect evidence evaluation, given the long latency period for breast cancer radiation therapy recurrence and late effects. In this consensus statement, we assess the data available to the radiation oncology community of proton therapy for breast cancer, provide expert consensus recommendations on indications and technique, and highlight ongoing trials' cost-effectiveness analyses and key areas for future research. (c) 2021 Elsevier Inc. All rights reserved.

Purpose: Moderately hypofractionated radiation therapy represents an effective treatment for localized prostate cancer (PC). Although large randomized trials have reported the efficacy of photon-based hypofractionated therapy, hypofractionated proton therapy (HFPT) has not been extensively studied. This study was performed to determine the clinical and patient-reported outcomes for patients with PC treated with HFPT.Methods and Materials: Between 2010 and 2017, 184 men were enrolled on a trial of 70 Gy in 28 fractions of HFPT for low- to intermediate-risk PC. Acute and late toxicity was evaluated using National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Patient-reported outcomes were measured by International Prostate Symptom Score, International Index of Erectile Function Questionnaire, and Expanded Prostate Cancer Index Composite scores.Results: Median follow-up was 49.2 months. Enrolled patients had low-risk (n = 18), favorable intermediate-risk (n = 78), and unfavorable intermediate-risk (n = 88) PC. Four-year rates of biochemical-clinical failure-free survival were 93.5% (95% confidence interval, 89%-98%), 94.4% (89%-100%), 92.5% (86%-100%), and 93.8% (88%-100%) in the overall group and the low-risk, favorable intermediate-risk, and unfavorable intermediate-risk cohorts, respectively (log-rank P > .4). The incidence of acute grade 2 or higher gastrointestinal (GI) and urologic toxicities were 3.8% and 12.5%, respectively. The 4-year incidence of late grade 2 or higher urologic and GI toxicity was 7.6% (4%-13%) and 13.6% (9%-20%), respectively. One late grade 3 GI toxicity was reported. All late toxicities were transient. Patient-reported International Prostate Symptom, International Index of Erectile Function, and Expanded Prostate Cancer Index Composite scores had no significant long-term changes after completion of HFPT (Supplementary Table 1, available at https://doi.org/10.1016/j.ijrobp.2019.05.069).Conclusions: HFPT is associated with low rates of toxicity and does not appear to negatively affect 4-year patient reported urinary and bowel health. Further comparative analyses are warranted to better understand differences between proton and photon HFRT. (C) 2019 Elsevier Inc. All rights reserved.

The introduction of new radiation therapy treatment techniques such as intensity modulated radiotherapy and volumetric modulated arc therapy cause well established dosimetry systems to be extended to their capability limits. Optical fibre dosimetry systems offer several advantages over conventional dosimeters for real time dosimetry. This thesis considered the use of a novel inorganic scintillation detector based on a terbium doped gadolinium oxysulphide inorganic scintillator. Essential dosimetry characterisation of the inorganic scintillation detector system for external beam radiotherapy was evaluated. Results obtained demonstrated promising characteristics when used in external beam radiation therapy settings. However, the system overestimated the dose when measuring percentage depth dose and lateral dose profiles. The contribution of Cerenkov radiation and the absorbed-dose energy dependence to the overall signal measured with the inorganic scintillation detector system was also considered in this work. To achieve this, an accurate Cerenkov removal technique using the hyperspectral approach and accurate Monte Carlo model of the linear accelerator was used. Results obtained suggest mechanisms other than the stem effect and the absorbed-dose energy dependence influence the response of the inorganic scintillation detector system at depth.

Objective To report medium-term oncological outcomes in men receiving primary focal treatment with high-intensity focused ultrasonography ( HIFU) for prostate cancer (PCa). Patients and methods Consecutive patients with PCa treated with primary focal HIFU at two centres by six treating clinicians were assessed. Patients were submitted to either focal ablation or hemi-ablation using HIFU (Sonablate 500). The primary objective of the study was to assess medium-term oncological outcomes, defined as overall survival, freedom from biopsy failure, freedom from any further treatment and freedom from radical treatment after focal HIFU. The secondary objective was to evaluate the changes in pathological features among patients treated with focal HIFU over time. We also assessed the relationship between year of surgery and 5-year retreatment probability. Results A total of 1032 men treated between November 2005 and October 2017 were assessed. The median age was 65 years and median prostate-specific antigen level was 7 ng/mL. The majority of patients had a Gleason score of 3 + 4 or above (80.3%). The median (interquartile range) follow-up was 36 (14-64) months. The overall survival rates at 24, 60 and 96 months were 99%, 97% and 97%, respectively. Freedom from biopsy failure, defined as absence of Gleason 3 + 4 disease, was 84%, 64% and 54% at 24, 60 and 96 months. Freedom from any further treatment was 85%, 59% and 46% at 24, 60 and 96 months, respectively. Approximately 70% of patients who were retreated received a second focal treatment. Freedom from radical treatment was 98%, 91% and 81% at 24, 60 and 96 months. During the study period, we observed an increase in the proportion of patients undergoing focal HIFU with Gleason 3 + 4 disease and with T2 stage disease as defined by multiparametric magnetic resonance imaging. Finally, there was a reduction over time in the proportion of patients undergoing re-treatment within 5 years of first treatment. Conclusions Focal HIFU for PCa is a feasible therapeutic strategy, with acceptable survival and oncological results and a reduction in the 5-year retreatment rates over the last decade. Re-do focal treatment is a feasible technique whose functional and oncological outcomes have still to be evaluated.

Objective: to evaluate the efficiency of beam radiotherapy (BRT) in patients with non-muscle-invasive bladder cancer (NMIBC).Subjects and methods. The data on 40 patients diagnosed as having stage T1 NMIBC, who had been treated at the Medical Radiology Center in 1990 to 2009, were studied. Of them, 75% were aged < 70 years. They all had verified transitional cell carcinoma: G1 in 11 (27.5%) patients; G2 in 12 (30%), and G3 in 17 (42.5%). Multifocal tumor growth (T1m) was found in 22 (55%); the largest tumor exceeded 3 cm in 31 (77.5%). More than half (60%) of the patients had clinically significant concomitant diseases. Three (7.5%) had a history of treated malignancy. The mean follow-up of the patients was 58.6 months.Results. Survival at 60 months follow-up was 67.9 ± 8.0%. Three (7.5 %) patients died at 21–42 months follow-up. Five-year relapse-free survival was 50.0 ± 8.5%. Seven (17.5 %) patients were withdrawn at 5 to 99 months follow-up (mean 34.7 months). Four (10 %) patients died from disease progression at 21 to 143 months follow-up. After radiotherapy to the bladder area, 17 (42.5 %) patients were diagnosed as having more than 50 % tumor regression, which permitted transurethral resection of a residual tumor. The frequency and degree of radiation reactions were estimated. Acute radiation cystitis was diagnosed in 11 (27.5 %) patients and rectitis was found in 6 (15.0 %). Radiation reactions were not a reason for forced treatment discontinuation. Grade I-II late radiation cystitis (RTOG/EORTC) was diagnosed in 9 (22.5 %) patients.Conclusion. The efficiency of BRT in patients with NMIBC who had refused surgical treatment or had contraindications to it was confirmed during the study. BRT could preserve the functioning bladder in 97.5 % of cases and remove the residual tumor in 42.5 %. Radiation reactions were not a reason for forced treatment interruption.

Background: Cervical carcinoma is the second most common neoplasm in women worldwide and is the most frequent cancer among women in Bangladesh. In recent years, High Dose Rate (HDR) brachytherapy in combination with External Beam Radiotherapy (EBRT) has been popular in the management of cancers of uterine cervix.Objectives: To evaluate the effectiveness and acute toxicity of four fractions high dose rate intracavitary brachytherapy following pelvic external beam radiotherapy in the treatment of locally advanced cervical carcinoma. Methods: Bangabandhu Sheikh Mujib Medi­cal University & NICRH chosen as a research place for EBRT and HOR brachytherapy. A typical radiotherapy treatment involves daily inadiation for several weeks. Whole pelvis was treated with total dose of SO Gy in 5 weeks. Patients were treated once a day, 5 days a week with a daily fraction size of 2.0 Gy. EBRT: Pelvic radiotherapy dose is 50 Gy in 25 fractions (2.0 Gy per fraction) over 5 weeks. HDR brachytberapy dose is 7 Gy per fraction, total 4 fractions, each in a week over 4 weeks. Results: Ninety-eight patients were entered in the study. Three patients were excluded due to active non-malignant diseases. One patient had active tuberculosis, two patients had severe skin reactions and two patients withdrew following the first HDR application. The remaining Ninety patients were analyzed. Ninety patients completed the prescribed treatment and were evaluated. Eighty had complete response with relief of symptoms, negative Pap-smear and no clinical signs of persistence disease at 3 months. Ten patients had a positive Pap-smear with clinical signs of persis­tence disease. Patients were evaluated before statting treatment with EBRT and before starting treatment with HDR ICBT. Conclusion: It can be easily concluded that 4 fractions of HDR ICBT, 7 Gy each weekly and pelvic EBRT can effectively and safely control locally advanced carcinoma of the uterine cervix. So that EBRT and HDR ICBT is an acceptable treatment for locally advanced carcinoma of the uterine cervix. Careful attention to normal tissue doses such as the rectum, bladder, and small bowel is important in the treatment of locally advanced cervical cancer.

To investigate the feasibility of delivering a single large dose of intraoperative electron beam radiotherapy (IORT) to the liver of clinically normal and partially hepatectomized beagles, an experimental study was designed, The purpose of the study was to obtain dose guidelines for the delivery of IORT to the liver of human patients with colorectal cancer metastases to the liver, After partial resection of the liver, IORT in doses up to 30 Gy was applied to the resection plane as well as to a nonsurgically manipulated part of the liver of 25 beagles, The temporal sequence of histologic changes of these irradiated parts of the liver tissue was investigated, There were no postoperative complications and no morbidity or mortality associated with a minimal follow-up of 3 years, Necropsy performed 3 months after IORT revealed only mild histopathologic changes, One year after IORT, more distinct histopathologic changes consisting of capsular thickening, diffuse parenchymal fibrosis, and subcapsular hepatocellular atrophy were found, Three years after IORT, the parenchymal architecture seemed to be restored, although loss of liver tissue was definitive at the irradiation site; liver function remained intact, These results indicate that IORT to part of the liver in the canine model can be safely applied and that, although doses up to 30 Gy can result in severe local tissue damage, wound healing and liver function are not disturbed.

To investigate the feasibility of delivering a single large dose of intraoperative electron beam radiotherapy (IORT) to the liver of clinically normal and partially hepatectomized beagles, an experimental study was designed, The purpose of the study was to obtain dose guidelines for the delivery of IORT to the liver of human patients with colorectal cancer metastases to the liver, After partial resection of the liver, IORT in doses up to 30 Gy was applied to the resection plane as well as to a nonsurgically manipulated part of the liver of 25 beagles, The temporal sequence of histologic changes of these irradiated parts of the liver tissue was investigated, There were no postoperative complications and no morbidity or mortality associated with a minimal follow-up of 3 years, Necropsy performed 3 months after IORT revealed only mild histopathologic changes, One year after IORT, more distinct histopathologic changes consisting of capsular thickening, diffuse parenchymal fibrosis, and subcapsular hepatocellular atrophy were found, Three years after IORT, the parenchymal architecture seemed to be restored, although loss of liver tissue was definitive at the irradiation site; liver function remained intact, These results indicate that IORT to part of the liver in the canine model can be safely applied and that, although doses up to 30 Gy can result in severe local tissue damage, wound healing and liver function are not disturbed.