Prognostic value of quality of life scores for time to progression (TTP) and overall survival time (OS) in advanced breast cancer

The purpose of the study was to investigate whether baseline quality of life (QoL) and changes in QoL scores from baseline are prognostic for time to progression (TTP) and/or overall survival (OS) in patients with advanced breast cancer receiving docetaxel (T) or sequential methotrexate and 5-fluorouracil (MF). QoL was assessed at baseline and before each treatment using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30). Survival curves and probabilities were estimated using the Kaplan–Meier technique. The Cox proportional hazards regression model was used for both the univariate and multivariate analyses to explore relationships between baseline QoL variables and TTP, as well as OS. In the univariate analysis, more severe pain and fatigue at baseline were predictive for a shorter OS; global QoL, physical functioning and appetite loss had a borderline significance (P=0.0130 for global QoL; P=0.0256 for physical functioning: P=0.0149 for appetite loss). World Health Organization (WHO) performance status was significantly predictive for OS. In the multivariate analysis, more severe pain at baseline was predictive for a shorter OS. In contrast, baseline QoL had no prognostic value for the duration of TTP. QoL change scores from baseline QoL predicted neither OS nor TTP. Our findings suggest that while QoL measurements are important in evaluating patients’ QoL, they have no great importance in predicting primary clinical endpoints such as TTP or OS in advanced breast cancer patients.