Survival-adjusted health-related quality of life (HRQL) among patients with metastatic breast cancer receiving paclitaxel plus bevacizumab versus paclitaxel alone: results from Eastern Cooperative Oncology Group Study 2100 (E2100).

The purpose of this study was to examine health-related quality of life (HRQL) among women with metastatic breast cancer treated on E2100 with paclitaxel or paclitaxel plus bevacizumab. Trial participants (N = 670) completed the Functional Assessment of Cancer Therapy-Breast (FACT-B) pre-treatment and following 4 and 8 cycles of treatment to assess HRQL and breast cancer-specific concerns. A significantly higher proportion of missing FACT-B assessments was observed among patients receiving paclitaxel only, due to faster time to death. To account for this non-ignorable pattern of missing data, we conducted a survival-adjusted HRQL analysis by jointly modeling the longitudinal HRQL outcome and time to non-ignorable dropout using a two-stage model. FACT scores assessing HRQL did not differ following 4 and 8 cycles of treatment; however mean scores on the 9-item Breast Cancer Scale were significantly higher after 4 and 8 cycles of treatment among patients receiving paclitaxel plus bevacizumab. No differences were observed between treatment arms on FACT-B total scores. The addition of bevacizumab was not associated with additional side effect burden from the patient perspective and was associated with a greater reduction in breast cancer-specific concerns. No other differences were noted.