ESTRO 37 Abstract book

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ESTRO 37

3.1% of the HLRT one (p=0.79), usually as dermatitis. HLRT patients presented more frequently G1-2 dysphagia (30.6% vs 0.4%, p<0.001) and/or G1-2 lymphedema (5.6% vs 0.4%, p=0.002). At multivariate analysis, tabagism was the only independent factor statistically influencing the risk of acute toxicity (p=0.047). Concerning late toxicity, HLRT patients presented more frequently G1-2 lymphedema (6.2% vs 0.7%, p=0.003). Noteworthy, there were significantly more patients presenting a postoperative lymphedema (any grade) in the HLRT than HRT arm (5% vs 0.4% p=0.005). When we excluded these patients with any grade of lymphedema before RT (n = 9) and those where this information was lacking in the clinical chart (n =5), only 2 patients presented a G2 lymphedema (both treated with HLRT) and 8 a G1 lymphedema (5 treated with HLRT and 3 with HRT). This difference in the incidence of G1-2 lymphedema in our 2 cohorts was significantly different (two-tailed Fisher Exact p-value 0.041). Median follow-up was 61.7 months. Five-year OS was 96.4% and 92.6% in the HRT and in the HLRT group, respectively (p=0.027). Five-year LRR-FS was 96.3% and 92% in the HRT and in the HLRT population, respectively (p=0.004). Five-year DFS was 92.2% and 83.4% in the HRT and in the HLRT population, respectively (p=0.004). Conclusion HLRT is safe and the clinical outcomes of our patients are comparable to the results of available randomized trials on hypofractionation for breast cancer. Further, prospective randomized trials comparing standard fractionated loco-regional RT and HLRT are warranted to confirm our data and consider HLRT as a standard of care. EP-1336 The role of adjuvant radiotherapy in male breast cancer patients in clinical practice P. Rogowski 1 , M. Pazos 1 , S. Schönecker 1 , D. Reitz 1 , M. Braun 2 , N. Harbeck 3 , J. Engel 4 , C. Belka 1 , S. Corradini 1 1 University Hospital- LMU Munich, Department of Radiation Oncology, Munich, Germany 2 Red Cross Hospital, Department of Obstetrics and Gynecology- Breast Centre, Munich, Germany 3 University Hospital- LMU Munich, Department of Obstetrics and Gynecology- Breast Centre, Munich, Germany 4 LMU Munich, Munich Cancer Registry MCR of the Munich Tumour Centre TZM at the Institute of Medical Information Processing- Biometry and Epidemiology IBE, Munich, Germany Purpose or Objective Male breast cancer (MBC) is a rare disease. To date, no consensus has been reached in regards to the most appropriate curative treatment strategy. The objective of the present observational study was to identify patient and tumour characteristics and to assess the role of radiotherapy (RT) in the MBC setting in clinical practice. Material and Methods Between 1998 and 2014, patients with MBC and treated at the breast centre of LMU and Redcross hospital of Munich were retrospectively evaluated. Patients were sub-stratified based on the addition of adjuvant RT. Data on overall survival, disease-free survival, local recurrence-free survival and distant metastasis-free survival were estimated with the Kaplan-Meier method and compared by log-rank testing. Results A retrospective consecutive cohort of 58 MBC patients was analysed. Median follow-up for the entire study population was 38 months. Twenty one out of 58 patients (36.2%) received adjuvant RT. Overall, patients receiving postoperative RT presented with more high-risk features. Patients receiving postoperative RT had significantly higher UICC-stage (UICC III in 50% vs 9.7%, p=0.018) and positive lymph nodes when compared to surgery alone

Conclusion The results of this cross-sectional study are a proof of concept that CTA is a useful to detect CAD after left breast irradiation, showing that for the irradiated group, there is a tendency to significance in the number and severity of coronal lesions when compared with the control group. For the irradiated group V30 looks as a better surrogate for CAD than Dmean. In view of these results, a prospective longitudinal study including a larger number of patients with base-line pre-radiotherapy imaging is being designed. Longer follow up is needed to establish if these early image findings correlate with future clinical manifestations. EP-1335 Efficacy and Safety of hypofractionated loco- regional radiotherapy for breast cancer patients. M. Caubet 1 , P. Bontemps 1 , A. Anota 2 , F. Boulbair 1 , Y. Hammoud 1 , K. Peigneaux 3 , G. Créhange 3 , B. De Bari 1 1 Hôpital Univ. Jean Minjoz CHU Minjoz Jeans & Belfort- Montbéliard Hospital, Radiation Oncology, Besançon, France 2 Methodology and Quality of life in Oncology Unit, Medical Oncology, Besançon, France 3 Georges François Leclerc Centre, Radiation Oncology, Dijon, France Purpose or Objective To retrospectively evaluate efficacy and safety of hypofractionated locoregional radiotherapy (HLRT) in breast cancer (BC) patients. We compared this schedule with a population of patients treated, in the same period, with hypofractionated radiotherapy on the breast/wall chest only (HRT). Material and Methods Clinical charts of patients with a biopsy-proven BC treated with postoperative HLRT (n= 275, 63%) or HRT (n= 160, 37%) between 2008 and 2011 were reviewed. Primary endpoint of the analysis was the incidence of acute and late toxicity retrospectively evaluated with the NCI-CTCAE v4.0 criteria. We also calculated and reported the 5-year locoregional-free survival (LRR-FS), disease- free survival (DFS) and overall survival (OS). Results Treatment was globally well-tolerated. Grade 3 (or more) acute toxicity was found in 4.4% of the HRT cohort and