Safety of bevacizumab in metastatic breast cancer patients undergoing surgery

Background: Evaluate the safety of surgery in relation to bevacizumab in the first-line treatment of metastatic breast cancer (mBC) in two international trials. Patients and methods: The incidence, type and timing of post-surgical bleeding events and wound-healing complications were assessed in surgical patients in the AVastin And DOcetaxel (AVADO) (NCT00333775) and Avastin THErapy for advaNced breAst cancer (ATHENA) (NCT00448591) trials. Both study protocols followed recommendations to withhold bevacizumab for at least 6 weeks before elective surgery and to wait 28 days (or until the wound was fully healed) after major surgery before recommencing bevacizumab therapy. Results: In AVADO, 221 surgical procedures (55 major, 166 minor) were performed in 155 patients. In ATHENA, 1190 surgical procedures (435 major, 755 minor) were performed in 672 patients. One bevacizumab-treated AVADO patient (0.9%) who underwent surgery experienced a grade 3 bleeding event. In ATHENA, six patients (0.9%) who underwent surgery experienced grade 3 bleeding events and one patient (0.1%) experienced a grade 4 bleeding event. No grade 5 bleeding events in patients undergoing surgery were reported in either study. One grade 3 wound-healing complication was reported in each of the AVADO arms: placebo (n = 46, 2.2%), bevacizumab 7.5 mg/kg (n = 57, 1.8%) and bevacizumab 15 mg/kg (n = 52, 1.9%). Incidence of grade 3-4 wound-healing complications in ATHENA was 2.2% and 1.3% in patients undergoing minor or major surgery, respectively. Conclusions: Surgery can be performed on patients with mBC undergoing bevacizumab therapy with a low risk of severe bleeding or wound-healing complications post surgery, if current labelling recommendations are adhered to.