[INTRAOPERATIVE RADIOTHERAPY (IORT) IN EARLY BREAST CANCER - 500 PATIENTS, ONE CENTER'S EXPERIENCE].

Abstract

AIMS: To present our Institute's experience with intraoperative radiotherapy in this selected population by collecting and analyzing clinical data, including long-term follow-up. BACKGROUND: Breast-conserving therapy is the standard treatment for early-stage breast cancer. The treatment includes tumor resection and a whole breast irradiation. Intraoperative radiotherapy is a single dose of irradiation given to the tumor bed immediately after it is removed. This treatment is suitable for a selected population of patients with early stage breast cancer, which constitutes about 20% of all breast cancer patients and is supposed to replace the standard whole breast radiation treatment. METHODS: Between the years 2006-2017, 737 women with early breast cancer were treated in Carmel Medical Center with intraoperative radiotherapy. We herein report the results of the first 500 patients who were treated until 2015. RESULTS: In 13.8% of the patients, additional breast treatment was recommended due to poor pathological characteristics of the disease in final pathological examination. During a median follow-up period of 74 months (1-136), recurrence was observed in 22 patients (4.4%), and in 7 patients (1.4%) recurrence was observed in regional lymph nodes; 13 patients (2.6%) developed metastatic disease. Risk factors for regional recurrence were identified: tumor size greater than 2 cm, lack of adjuvant therapy and poor genetic profile of the disease. CONCLUSIONS: Intraoperative radiotherapy is feasible and may offer an alternative to the standard whole breast radiotherapy, in low risk early breast cancer patients. The patients should be selected according to known risk factors.