Prognostic Value of Volumetric Parameters of Pretreatment 18F-FDG PET/CT in Esophageal Cancer: A Systematic Review and Meta-analysis

Purpose We performed a systematic review and meta-analysis on the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) derived from pretreatment F-18-FDG PET/CT in patients with esophageal cancer. Methods PubMed and EMBASE databases were searched until April 12, 2018, for studies that evaluated MTV or TLG as prognostic factors in esophageal cancer, with overall survival (OS) and event-free survival serving as the end points. Hazard ratios (HRs) were meta-analytically pooled using a random-effects model. Subgroup analyses based on the clinicopathological and PET variables were performed. Results In total, 16 studies with 1294 patients were included. The pooled HRs of MTV and TLG for OS were 2.26 (95% confidence interval [CI], 1.73-2.96) and 2.23 (95% CI, 1.73-2.87), respectively. Regarding event-free survival, the pooled HRs of MTV and TLG were 2.03 (95% CI, 1.66-2.49) and 2.57 (95% CI, 1.82-3.62), respectively. Metabolic tumor volume was found to be a significant prognostic factor for OS consistently across multiple subgroups classified based on stage, histological subtype, treatment, delineation of volume of interest, and the determination method of cutoff value, with pooled HRs ranging from 1.96 to 2.54. Conclusions In patients with esophageal cancer, MTV and TLG derived from pretreatment F-18-FDG PET are significant prognostic factors. As prognostic biomarkers, volumetric metabolic parameters may bolster the role of F-18-FDG PET in the management of esophageal cancer.