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)

Abstract

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.

Fig. 1

Mean FACT-G scores per treatment arm across assessment time points. FACT-G functional assessment of cancer therapy—general questionnaire. See www.facit.org for full item content. The vertical bars represent standard deviations

Fig. 2

Mean TOI scores per treatment arm across assessment time points. TOI trial outcome index from the functional assessment of cancer therapy—breast questionnaire. See www.facit.org for full item content. The vertical bars represent standard deviations

Fig. 3

Mean FACT-BCS scores per treatment arm across assessment time points. BCS: functional assessment of cancer therapy breast cancer subscale items include content covering dyspnea, lymphedema, alopecia, weight change, pain, change in appearance, feeling self-conscious about attractiveness, and fear of family members getting cancer and fear about the effects of stress on illness. See www.facit.org for full item content. The vertical bars represent standard deviations