Efficacy and safety of bevacizumab-containing therapy for refractory advanced breast cancer: a retrospective study

Background: Advanced breast cancer (ABC) is difficult to treat due to the primary and acquired resistance, which is the main cause of rescue treatment failure. Thus, developing a new rescue treatment strategy for clinicians is a challenge. This study retrospectively collected the medical information of patients with refractory ABC who were treated with bevacizumab at our department to analyze the efficacy and safety of bevacizumab-containing therapy as a new treatment method for refractory ABC. Methods: The complete medical information of patients receiving bevacizumab treatment from November 2017 to November 2020 was collected, and patients' general medical history and disease characteristics were analyzed. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), time to failure (TTF), overall survival (OS), and safety were also analyzed using SPSS 20.0 statistical software. Results: The data of 68 women with refractory ABC who received bevacizumab-containing therapy were collected. The last follow-up examinations were performed on March 31, 2021. The ORR was 41.2% and the DCR was 88.2%. The median PFS, TTF, and OS were 6.0 months [95% confidence interval (CI): 3.4-8.6 months], 4.0 months (95% CI: 3.2-4.8 months), and 26.6 months (95% CI: 10.2-43.0 months), respectively. Treatment was discontinued in 2 patients due to chemo-related adverse reactions. The main adverse events related to bevacizumab were hypertension (7.4%) and bleeding (2 cases, 2.9%), both of which were grade 1. No specific adverse events causing the discontinuation of bevacizumab treatment were observed in the other patients. Conclusions: Among patients with refractory ABC, bevacizumab-containing therapy is feasible and safe, and can be used as a new treatment strategy. However, the question of who can benefit the most from bevacizumab-containing therapy requires further exploration.