Aim: Diffuse splenic 18F-Fluorodeoxyglucose (FDG) uptake has shown to be associated with concurrent inflammation. We evaluated the prognostic value of diffuse splenic FDG uptake for predicting prognosis in cholangiocarcinoma patients.
Patients, methods: Sixty-four patients with unresectable cholangiocarcinoma performed Positron emission tomography/computed tomography (PET/CT) using FDG between July 2009 and April 2012. Patients were divided into two groups according to splenic FDG uptake relative to hepatic FDG uptake. Eleven patients showing splenic FDG uptake exceeding hepatic uptake were included in group A, while 53 patients with hepatic FDG uptake exceeding splenic uptake were included in group B. Prognostic factors for overall survival were evaluated using log-rank test. Variables with a probability of less than or equal to 0.1 on univariate analysis were considered as possible independent factors. Cox-proportional hazards model was used to analyze univariate and multivariate analysis.
Results: Mean standardized uptake value of the liver (Liver SUVmean)/Spleen SUVmean (L/S) ratio <1 (p = 0.0034), WBC > 10 000 (p = 0.1155) and CEA >30 (p = 0.0946) were predictors of overall survival on univariate analysis. In a subsequent multivariate analysis, L/S ratio <1 remained a significant independent predictor of poor prognosis (HR 6.0153, 95% CI, 1.7193-21.0460, p = 0.0052).
Conclusion: Our study has shown that splenic FDG uptake could be a predictor of overall survival of unresectable cholangiocarcinoma patients.
Keywords: PET; cholangiocarcinoma; spleen.