Value of (18)F-FDG PET for Predicting Response to Neoadjuvant Therapy in Rectal Cancer: Systematic Review and Meta-Analysis.

OBJECTIVE. The purpose of this study was to assess the predictive value of 18F-FDG PET/ CT for pathologic response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer. MATERIALS AND METHODS. A systematic search was performed (PubMed and Cochrane databases) for potentially relevant studies up to January 2014. Pooled sensitivity and specificity were calculated. The AUCs of the global cohort and for “major response,” “complete response,” “only PET after chemoradiotherapy,” “ad interim PET,” “major response excluding ad interim studies,” “complete response excluding ad interim studies,” “response index (RI),” “posttreatment maximum standardized uptake value (SUVmax post),” “visual response analysis (VRA),” “percentage reduction of the total lesion glycolysis (ΔTLG),” and “percentage reduction of the metabolic tumor volume (ΔMTV)” were analyzed. Heterogeneity was explored for multiple variables. Pooled prevalence and 95% CI were calculated. RESULTS. Thirty-four of 131 (26%) initial articles met ...