Metaanalysis of the correlation between radiographic tumor response and patient-reported outcomes

BACKGROUND. The primary aim of the current study was to determine whether radiographic tumor response is associated with patient-reported outcomes such as symptom response or health-related quality of life. METHODS. A metaanalysis was conducted of 21 available studies from 1995-2003 that provided data sufficient for examining the association between tumor response and patient-reported outcomes, including symptom response and health-related quality of life. A second aim was to examine the influence of possible moderating study variables on effect size variation. RESULTS. As hypothesized, patient-reported outcome improvement rates were most frequently associated with patients classified as a complete or partial response (CR/PR), followed by those with stable disease (SD) and progressive disease (PD). Moderate effect sizes were observed between the CR/PR and SD (effect size of 0.35) and CR/PR and PD categories (effect size of 0.43). A weak effect size was found between SD and PD (effect size of 0.16), raising concern over the meaningfulness of the SD category. No significant correlations were found between effect size and patient or study characteristics. Significant associations existed between treatment duration and age, study duration, survival, and symptom response rates, especially among PD patients. CONCLUSION. Despite significant study-to-study heterogeneity, an important association exists in the correlation between tumor response and formal measures of change in patient-reported outcomes. A better understanding of this relation would be enhanced if future reports included estimates of effect size in patient-reported outcome change by tumor response category. Practical implications, limitations, and directions for future research are provided.