Correlation between 18F-FDG PET/CT metabolic parameters and microvascular invasion before liver transplantation in patients with hepatocellular carcinoma

Abstract

Background Microvascular infiltration (MVI) before liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) is associated with postoperative tumor recurrence and survival. MVI is mainly assessed by pathological analysis of tissue samples, which is invasive and heterogeneous. PET/computed tomography (PET/CT) with 18F-labeled fluorodeoxyglucose (18F-FDG) as a tracer has been widely used in the examination of malignant tumors. This study investigated the association between 18F-FDG PET/CT metabolic parameters and MVI before LT in HCC patients. Methods About 124 HCC patients who had 18F-FDG PET/CT examination before LT were included. The patients’ clinicopathological features and 18F-FDG PET/CT metabolic parameters were recorded. Correlations between clinicopathological features, 18F-FDG PET/CT metabolic parameters, and MVI were analyzed. ROC curve was used to determine the optimal diagnostic cutoff value, area under the curve (AUC), sensitivity, and specificity for predictors of MVI. Result In total 72 (58.06%) patients were detected with MVI among the 124 HCC patients. Univariate analysis showed that tumor size (P = 0.001), T stage (P < 0.001), maximum standardized uptake value (SUVmax) (P < 0.001), minimum standardized uptake value (SUVmin) (P = 0.031), mean standardized uptake value (SUVmean) (P = 0.001), peak standardized uptake value (SUVpeak) (P = 0.001), tumor-to-liver ratio (SUVratio) (P = 0.010), total lesion glycolysis (TLG) (P = 0.006), metabolic tumor volume (MTV) (P = 0.011) and MVI were significantly different. Multivariate logistic regression showed that tumor size (P = 0.018), T stage (P = 0.017), TLG (P = 0.023), and MTV (P = 0.015) were independent predictors of MVI. In the receiver operating characteristic curve, TLG predicted MVI with an AUC value of 0.645. MTV predicted MVI with an AUC value of 0.635. Patients with tumor size ≥5 cm, T3-4, TLG > 400.67, and MTV > 80.58 had a higher incidence of MVI. Conclusion 18F-FDG PET/CT metabolic parameters correlate with MVI and may be used as a noninvasive technique to predict MVI before LT in HCC patients.