ESTRO 37 Abstract book

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ESTRO 37

reconstruction accounts for around 70% of all reconstructions. However, acute and long-term complications rates still remain a concern, especially if postmastectomy radiation therapy (PMRT) is delivered. Moreover, PMRT indication is increasing over time, since improved disease free-survival has been demonstrated also in the case of a limited axillary involvement. The aim of our study is to report the safety of PMRT after subcutaneous breast reconstruction using E/I and PMRT. Material and Methods We performed a retrospective analysis on 345 consecutive non metastatic breast cancer patients (T1-3, N0-3) treated by multimodal approach at the University of Florence between January 2012 and May 2016. All patients received mastectomy with immediate subcutaneous E/I reconstruction. Among them, 43 patients received PMRT on the chest wall and 3-4 axillary levels (50 Gy in 25 fractions). Capsular contracture, rippling, implant’s profile visibility, implant borders tangibility at smooth touch, and aesthetic result evaluation was conducted by two different physicians at the same time, giving a single agreed score for every item. Radiation treatment tolerance was assessed using the acute radiation morbidity scoring criteria and late radiation morbidity scoring scheme from the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC). Results Main patients and treatments characteristics are summarized in Table 1. Acute surgical complications were observed in five cases (11.6%): four wound skin infections, and one hematoma. Among them, two patients required E/I substitution. At a median follow up time of 30 months (mean 38.4; range 18 - 60), two cases of late complications after PMRT have been observed (4.6%), both showing capsule contraction. Concerning early late radiation-related side effects, we observed two skin fibrosis (4.6%), one hyperpigmentation (2.3%), one telangiectasia (2.3%); overall four cases of any breast skin toxicity were recorded (9.3%). Five patients developed distant metastases (11.6%), while no local relapses were observed.

Conclusion Our experience showed low rates of acute and early late complications. Longer follow up time is strongly needed. PMRT seems to be feasible and safe after mastectomy with immediate subcutaneous E/I reconstruction. EP-1300 Efectiveness of once-weekly hypofractionated irradiation in 486 elderly breast cancer patients. X. Sanz 1 , N. Rodríguez 1 , P. Foro 1 , A. Reig 1 , I. Membrive 1 , M. Zhao 2 , P. Perez 1 , L. Montezuma 1 , R. Granado 1 , M. Algara 1 1 Parc de Salut Mar, Radiation Oncology, Barcelona, Spain 2 Universitat Autonoma de Barcelona, Medicine, Barcelona, Spain Purpose or Objective Radiation therapy plays a key role in the multi- disciplinary treatment of breast cancer. The usual schedule requires patients to come to the radiotherapy center f or daily treatment, however, elderly patients with qassociated diseases that alter the general condition do not tolerate long periods of daily irradiation. The objective of this study is to analyze the results of weekly hypo-fractionated treatment in these patients. Material and Methods Between 1996 and 2016, we have included elderly patients carrying several concomitant pathology or socio- familial problems in which it is not feasible to propose conventional treatment. Patients with I-II stages