Prognostic Role of 18F-FDG Positron Emission Tomography in Patients with Resectable Hepatocellular Carcinoma

Abstract

Introduction: 18F-fluorodeoxyglucose positron emission tomography(18F-FDG PET) could predict tumour biology and aggressive of hepatocellular carcinoma(HCC). We hypothesized that 18F-FDG PET predicted survival of patients with HCC who underwent hepatectomy. Method: This was a retrospective study at a university center in Hong Kong. Data was retrieved from a prospectively entered database. Maximum standard uptake value(SUVmax) of tumor/ normal liver uptake(T/L ratio) was recorded. The PET positivity for overall survival(OS) was determined using T/L ratio by c-statistics using receiver operating characteristic curve. Multivariate analyses with preoperative, pathological variables and PET positivity were performed to determine the prognostic significance of post-hepatectomy OS and recurrence. Results: From 2004 to 2019, 267 patients who had 18F-FDG PET before hepatectomy. The 5-year OS and disease free survival(DFS) were 64.8% and 40.5% respectively. The median follow-up was 45.3 months. Table 1 showed the baseline demographics, operative and pathological characteristics of all patients. The optimal cut-off of T/L ratio was 1.526 based on ROC(AUC 0.674, 95% CI 0.608-0.741, P<0.001). Using a T/L ratio cutoff at 1.526, it was found to be an independent predictor of OS [hazard ratio(HR) 1.762 (1.120-2.773), p=0.014] (Table2) and was associated with a better OS.(Figure1) PET positive HCC were more likely to recur (with 5-year DFS 45.8% vs. 33.1%, p=0.001) and had a shorter DFS (median survival 8.5 vs 50 months, p=0.001).(Figure 2) Conclusion: PET positivity using T/L ratio was an independent factor for OS in HCC patients who underwent hepatectomy. 18F-FDG PET could be explored as a potential radiological biomarkers for HCC aggressiveness.