Patient-reported pain and other quality of life domains as prognostic factors for survival in a phase III clinical trial of patients with advanced breast cancer
BACKGROUND
Patient-reported outcomes have been associated with survival in numerous studies across cancer types, including breast cancer. However, the Brief Pain Inventory-Short Form (BPI-SF) and the Rotterdam Symptom Checklist (RSCL) have rarely been investigated in this regard in breast cancer.


METHODS
Here we describe a post hoc analysis of the prognostic effect of baseline scores of these instruments on survival in a phase III trial of patients with advanced breast cancer who received gemcitabine plus paclitaxel or paclitaxel alone after anthracycline-based adjuvant or neoadjuvant therapy. The variables for this analysis were baseline BPI-SF "worst pain" and BPI-SF "pain interference" scores, and four RSCL subscales (each transformed to 0-100). Univariate and multivariate Cox models were used, the latter in the presence of 11 demographic/clinical variables. Kaplan-Meier curves and log-rank tests were used to compare survival for patients by BPI-SF or RSCL scores.


RESULTS
Of 529 randomized patients, 286 provided BPI-SF data and 336 provided RSCL data at baseline. Univariate analyses identified BPI-SF worst pain and pain interference (both hazard ratios [HR], 1.07 for a 1-point increase; both p ≤ 0.0061) and three of four RSCL subscales [activity level, physical distress, and health-related quality of life (HRQOL) (HR, 0.86-0.91 for 10-point increase all p ≤ 0.0104)], to have significant prognostic effect for survival. BPI-SF worst pain (p = 0.0342) and RSCL activity level (p = 0.0004) were prognostic in the multivariate analysis. Median survival for patients categorized by BPI-SF worst pain score was 23.8 (n = 91), 17.9 (n = 94) and 14.6 (n = 94) months for scores 0, 1-4, and 5-10, respectively (log-rank p = 0.0065). Median survival was 23.8 and 14.6 months for patients (n = 330) with above- and below-median RSCL activity level scores respectively (log-rank p < 0.0001).


CONCLUSION
Pretreatment BPI-SF worst pain and RSCL activity scores provide distinct prognostic information for survival in patients receiving paclitaxel or gemcitabine plus paclitaxel for advanced breast cancer even after controlling for multiple demographic and clinical factors.


TRIAL REGISTRATION
Clinicaltrials.gov, NCT00006459.