ESTRO 36 Abstract Book

S343 ESTRO 36 _______________________________________________________________________________________________

6.5% (HER2 enriched), and 7.6% (triple negative) respectively. The median time interval from primary diagnosis to development of brain metastases were 99.5 months (luminal A), 58 months (luminal B), 37 months (luminal/HER2), 24 months (HER2 enriched), and 23 months (triple negative) respectively.

Conclusion The combination of reirradiation and hyperthermia is well tolerated and results in durable local control. ReRT+HT should be considered a standard adjuvant treatment option following surgery for patients with recurrent breast cancer. Late toxicity might be reduced by decreasing reRT fraction size and/or avoiding photon-electron abutments. PO-0657 Breast cancer subtypes and incidence/survival in patients with brain metastases Y.C. Tsai 1 , M.C. Liu 2 , H.C. Cheng 1 , J.J. Jian 1 , B.L. Yu 3 , C.M. Chen 3 , N.M. Chu 2 , C.F. Horng 4 , M.H. Tsou 5 1 Koo Foundation Sun Yat-Sen Cancer Center, Radiation Oncology, Taipei, Taiwan 2 Koo Foundation Sun Yat-Sen Cancer Center, Medical Oncology, Taipei, Taiwan 3 Koo Foundation Sun Yat-Sen Cancer Center, Surgery, Taipei, Taiwan 4 Koo Foundation Sun Yat-Sen Cancer Center, Clinical Research Office, Taipei, Taiwan 5 Koo Foundation Sun Yat-Sen Cancer Center, Pathology, Taipei, Taiwan Purpose or Objective Identify incidences and prognosis of breast cancer patients with brain metastases(BM) by breast cancer subtypes. We sought to determine whether a high-risk group could be defined in whom a search of occult BM was justified. Material and Methods Information was obtained from the institutional breast cancer data base. Between 1990 and 2010, 6037 newly diagnosed stage I to III breast cancer patients were included in this study to determine the incidence of brain metastases in different breast cancer subtypes. Retrospective survival analyses were performed in 136 BM per breast cancer subtypes. 90 BM patients had detailed clinical information to define the median time interval from primary diagnosis to development of brain metastases. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth receptor-2 (HER2) statuses were tested by immunohistochemical (IHC) staining, and HER2 FISH analysis conducted for IHC 2+. Results With a median follow-up of 80 months. The incidence of CNS relapse was 2.8%. For stage I, II, III, the BM incidence was 0.9%, 2.1% and 6.5% respectively. Incidence of BM were 1% (luminal A), 1.8% (luminal B), 3.9% (luminal/HER2), 6.5% (HER2 enriched), and 4.6%(triple negative) respectively. Among 1503 stage III patients, the Incidence of BM were 2.1% (luminal A), 1.5% (luminal B), 9.9% (luminal/HER2), 13.2% (HER2 enriched), and 12.4%(triple negative) respectively. One year survival with BM were 40% (luminal A), 46.7% (luminal B), 54.2% (luminal/HER2), 39.1% (HER2 enriched), and 42.4% (triple negative) respectively. Three-year survival with BM were 24% (luminal A), 33.3% (luminal B), 9% (luminal/HER2),

Conclusion Subtype of breast cancer patients with triple-negative or HER2-positive had an increased risk for the development of brain metastases and shorter 3-year survival. The median time interval from primary diagnosis to development of brain metastases were shorter (2 years) for triple negative and HER2-positive patients. Stage III breast cancer patients with triple-negative or HER2- positive subtype may deserve a search of occult BM in the first 2 years after primary diagnosis. PO-0658 impact of breast radiation therapy on complications after alloplastic breast reconstruction C.D.L.G. Chaves 1 , H.D.A. Carvalho 2 , T.D.C. Saraiva 1 , T.T. Fuzisaki 2 , G.N. Marta 1,3 , R. Casagrande 4 , A. Munhoz 4 , J.A. Brasil 4 , S.R. Stuart 2 1 Instituto do Câncer do Estado de São Paulo ICESP - Faculdade de Medicina da Universidade de São Paulo, Radiation Oncology, Sao Paulo, Brazil 2 Faculdade de Medicina da Universidade de São Paulo, Radiation Oncology, Sao Paulo, Brazil 3 Hospital Sírio-Libanês, Radiation Oncology, São Paulo, Bazil 4 Instituto do Câncer do Estado de São Paulo ICESP - Faculdade de Medicina da Universidade de São Paulo, Division of Plastic Surgery, Sao Paulo, Brazil Purpose or Objective To assess the influence of radiation therapy (RT) in local complications in breast cancer patients who underwent breast reconstruction with alloplastic material. Material and Methods Between 2009 and 2013, patients with breast cancer who received alloplastic breast reconstruction with tissue expander (with included or remote valve), prosthesis- expander or breast implant were assessed retrospectively. Patients with at least 2 years of follow-up after the end of treatment were included. Complications were considered when any surgical intervention was required. Early complications, up to three months after surgery and late complications, after 6 months of the end of the surgery or RT. Uni and multivariate analysis were performed to correlate clinical variables with complications. Results In the studied period, 251 patients were evaluated. The mean age was 49.7 years and mean Body Mass Index (BMI) was 27.5 kg/m 2 . Most patients (73%) had diabetes mellitus; 35.5% had hypertension and 10.6% were smokers. Disease was presented in early stage in 78.5%. Modified radical or