Evaluation at 3 years of concurrent bevacizumab and radiotherapy for breast cancer: Results of a prospective study.

PURPOSE: To determine the 3 years late toxicity among patients with non-metastatic breast cancer who received concurrent bevacizumab and locoregional radiotherapy.

MATERIAL AND METHODS: This is a single-arm, multicentre, prospective study, of the toxicity of adjuvant concomitant association of bevacizumab and radiotherapy in patients with breast cancer. Toxicity was assessed by the Common Terminology Criteria for Adverse Events version 3.0 during the radiotherapy and follow-up clinics at 12 and 36 months after its completion. The study was designed to evaluate the toxicity at one year, 3 years and 5 years.

RESULTS: Sixty-four patients were included from October 2007 to August 2010. All of them received concurrent adjuvant radiotherapy and bevacizumab (in 24 cases after primary systemic treatment). All patients received non-fractionated radiotherapy to breast or chest wall with or without irradiation of regional lymph nodes. Early toxicity has been previously reported. Median follow-up was 46.4 months (range: 18-77 months). Median age was 53 years old (range: 23-68 years). The 3-years overall survival was 93% (range: 87-100%). Evaluation of the toxicity at 3 years was available for 67% of the patients. There was a low rate of toxicity: 14% grade 1 pain, 9% grade 1 fibrosis, 2% grade 1 telangiectasia, 2% grade 1 paresis, 7% grade 1 lymphedema and 2% grade 3 lymphedema. No grade 4 toxicity was observed. No patient had a left ventricular ejection fraction below 50% at 3 years.

CONCLUSIONS: Concurrent bevacizumab with locoregional radiotherapy is associated with acceptable 3-years toxicity in patients with breast cancer.