18F-FDG PET in Liver Transplantation Setting of Hepatocellular Carcinoma Predicting Histology?

Purpose The aim of this study was to evaluate the prognostic value of F-18-FDG PET/CT by predicting histopathological findings in the pretransplant evaluation of patients with hepatocellular carcinoma (HCC). Patients and Methods F-18-FDG PET/CT findings of 34 patients with HCC who underwent liver transplantation were reviewed retrospectively. Visual and quantitative analysis (tumor standardized uptake values normalized to the background activity of the liver: SUVmax T/L) was done. PET tumor characteristics were compared with the histological analysis (differentiation and microvascular invasion). All patients were followed up (mean, 12 months). Results Ten patients showed tumoral uptake greater than background activity (PET+). Higher-grade tumor was more common in the F-18-FDG-avid tumor group (P < 0.05). PET+ also showed more microvascular invasion at explant pathology (P < 0.05). Only 1 patient PET+ developed HCC early recurrence (4 months) with an SUVmax T/L of 1.64. Conclusions F-18-FDG uptake is predictive for microvascular invasion and tumor differentiation. This examination has a prognostic value regarding tumor recurrence after liver transplantation for HCC.