Abstract P3-12-06: TOxicities of Locoregional Radiotherapy Associated with Bevacizumab in patients with non-metastatic breast cancer (TOLERAB): Final long-term evaluation

Abstract

Abstract Background and Purpose: Recent phase 3 clinical trials have evaluated the addition of bevacizumab (B) to standard chemotherapy in the treatment of patients with non-metastatic breast cancer. But few data are available about the tolerance of B with locoregional radiation therapy (RT). The objective was to evaluate the 5 years late toxicities of the concurrent B and RT in non-metastatic breast cancer. Material and methods: This is a multicenter prospective study including non-metastatic breast cancer patients enrolled in phase 3 clinical trials evaluating B with concurrent RT (BEATRICE, BETH, BEVERLY 1, BERVERLY 2) versus RT alone. All patients received neo-adjuvant or adjuvant chemotherapy and normo-fractionated breast or chest wall RT, with or without regional lymph nodes RT. B was administrated as an equivalent of 5 mg/kg every week for 1 year. The safety profile (using the Common Terminology Criteria for Adverse Events version 3.0) was evaluated at 1, 3 and 5 years after the completion of radiotherapy. Results: From October 2007 to January 2012, 151 patients totally included. Median follow-up was 60 months (36-84) and 5 years late toxicities were available for 104 patients (46 with B and RT, 58 with RT alone). Median age was 51 (22-81). 61% of patients received regional lymph nodes RT. The majority of tumor was triple negative (65.6%), tumor size <2cm (50%) and nodal status negative (63.8%). Median total dose of B was 15000 mg (13200 – 18550) and median duration was 11.2 months (11-12.6). No grade ≥3 toxicity was observed. Only 16 patients had grade 1-2 toxicities (8 treated with B and RT, 8 with RT alone): n=4 (3.8%) had grade 1 pain, n=5 (4.8%) had grade 1-2 fibrosis, n=1 (1%) had grade 2 telangiectasia and n=5 (4.8%) had grade 1-2 lymphoedema. No significant difference between the 2 arms was observed. One patient of 46 evaluated had Left Ventricular Ejection Fraction inferior to 50%. At 5 years, overall survival was 93.8%, disease free-survival 89% and locoregional free-survival 93.1 %. Conclusion: Concurrent B and locoregional RT provides acceptable 5-years toxicities in patients with non-metastatic breast cancer. No grade ≥3 toxicity was observed. Citation Format: Clément-Zhao A, Tanguy M-L, Cottu P, De La Lande B, Bontemps P, Lemanski C, Baumann P, Levy C, Peignaux K, Reynaud-Bougnoux A, Gobillion A, Kirova Y. TOxicities of Locoregional Radiotherapy Associated with Bevacizumab in patients with non-metastatic breast cancer (TOLERAB): Final long-term evaluation [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-12-06.