The role of preoperative [18F]fluorodeoxyglucose positron emission tomography in predicting early recurrence after curative resection of hepatocellular carcinomas.

Abstract

PURPOSE: (18)F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) scan reflects tumor differentiation and predicts clinical outcome in patients with hepatocellular carcinoma (HCC). We investigated the correlation of PET scans with tumor differentiation and early tumor recurrence (time-to-recurrence <1 year).

METHODS: We reviewed the medical records of 93 patients with HCC who underwent curative resection at our hospital from August 2004 through December 2008. PET scans were performed preoperatively, and the maximum standardized uptake value of the tumor (SUV(tumor)) and the tumor-to-non-tumor SUV ratio (TNR) were calculated from FDG uptake.

RESULTS: Twenty-six (27.9%) had recurrences and 12 of them (46.2%) had early recurrences. SUV(tumor) and TNR correlated strongly with tumor differentiation (p < 0.001). Early recurrence-free and the overall survival rates in the low TNR group (TNR <2.0) were higher than in the high TNR group (TNR ≥2.0) (p = 0.015, p = 0.013). According to univariate analysis, predictors of early tumor recurrence were large tumor size (≥5 cm), high TNR (≥2), high SUV(tumor) (≥4), and high Edmoson-Steiner grade. However, on multivariate analysis, none of the examined factors were statistically significant independent predictor.

CONCLUSION: PET scans reflect tumor differentiation in HCCs. Because high TNR (TNR ≥2) and SUV(tumor) (SUV ≥4) were these cutoff point significant predictors in univariate analysis, future studies with more statistical power are needed to assess the significance.