A 18FDG PET/CT-based volume parameter is a predictor of overall survival in patients with local advanced gastric cancer.

Objective: The present study investigated the prognosis value of preoperative fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with local advanced gastric cancer (LAGC).

Methods: In total, 144 patients [median age 63 (range: 48-80) years old] with LAGC underwent18F-FDG PET/CT prior to any treatment. The maximum standardized uptake values (SUVmax), mean standardized uptake values (SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary lesion were measured on PET/CT and correlated with clinicopathological features and survival.

Results: Significant differences in SUVmean, SUVmax, MTV and TLG were found according to Lauren's classification, histologic grade and T category (P<0.05). During the 26.5-month follow-up, 51 (35.4%) patients died and 70 (48.6%) exhibited disease progression. The optimal thresholds of MTV and TLG were 15.1 cm3 and 47.3 cm3, respectively. The 3-year progression-free survival (PFS) and overall survival (OS) for patients with high TLG values were 30% and 38% compared to 38% and 47% for low TLG values, respectively (P<0.05). Univariate and multifactor analyses demonstrated that lymph node metastasis and T stage were independent prognostic factors for PFS; T stage, histologic grade and TLG were independent prognostic factors for OS (P<0.05). Molecular markers had no relationship with patient's outcomes.

Conclusions: Metabolic activity of primary gastric tumors from 18F-FDG PET/CT is a prognostic factor in patients with LAGC.