Halim Ozcevik, Muge Oner Tamam
Objective: This study evaluates the prognostic significance of pretreatment [18F]FDG PET/CT metabolic parameters in esophageal cancer and identifies independent predictors of overall survival (OS). Methods: This retrospective single-center study included 152 treatment-naïve patients with histopathologically confirmed esophageal cancer who underwent staging [18F]FDG PET/CT between May 2015 and August 2025. SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured for the primary tumor. Overall survival was analyzed with Kaplan-Meier and Cox proportional hazards models, and cut-off values were derived by receiver operating characteristic (ROC) analysis. Results: During a median follow-up of 70 months, 106 patients (69.7%) died. In comparisons of median values, MTV and TLG were higher in patients who died (p = 0.004 and p = 0.035), whereas SUVmax and SUVmean did not differ; both volumetric indices were associated with shorter OS as continuous variables and when dichotomized at their ROC-derived cut-offs. Their discrimination was comparable and modest (AUC 0.647 and 0.608). A multivariable model incorporating high TLG achieved a Harrell's C of 0.715, at least as high as the primary MTV-based model (C = 0.687), so the data do not establish MTV as superior to TLG. In the primary multivariable model, distant metastasis (HR 2.46, 95% CI 1.53-3.98, p < 0.001), and high MTV (≥11.44 cm3; HR 1.79, 95% CI 1.18-2.71, p = 0.006) remained independent predictors of death. Conclusions: Volumetric [18F]FDG PET/CT indices (MTV and TLG) rather than SUVmax carried independent prognostic information for overall survival, alongside distant metastasis, supporting their use as an adjunct to established staging in pretreatment risk stratification, pending prospective multicenter validation.