Non-smooth tumor margins and the presence of non-hypervascular HBP hypointense nodules were demonstrated to be independent significant predictive factors of tumor recurrence after either hepatic resection or RFA.
Background & Aims: Gadoxetic acid-enhanced MR may provide prognostic information for hepatocellular carcinoma (HCC) patients. The aim of this study was to determine the significant predictive factors of tumor recurrence after curative treatment for single nodular HCCs ≤ 3 cm.
Methods: A total of 373 patients with single nodular HCCs ≤ 3 cm who underwent pre-treatment gadoxetic acid-enhanced MR followed by hepatic resection (n=143) or radiofrequency ablation (RFA) (n=230) were included. We retrospectively analyzed their clinicopathological and MR imaging features to determine which features may help predict presence of microvascular invasion (MVI) or recurrence-free survival (RFS). RFS was estimated using Kaplan-Meier analysis and significant predictive MR findings for RFS were evaluated using the Cox-proportional hazard regression model.
Results: Non-smooth tumor margins on hepatobiliary phase (HBP) imaging were significantly associated with MVI in 143 patients treated by hepatic resection (P=0.048, odds ratio=2.60 [1.01-6.69]). In addition, non-smooth tumor margins (Hepatic resection: P=0.012, hazard ratio [HR]=2.17 [1.19-3.97]; RFA: P=0.019, HR=1.79 [1.10-2.91]) and the presence of non-hypervascular HBP hypointense nodules (Hepatic resection: P=0.001, HR=3.55 [1.74-7.23]; RFA: P<0.001, HR=2.12 [1.40-3.20]) were demonstrated to be significant negative predictive factors of RFS after both hepatic resection and RFA. When high risk MR findings for recurrence were defined as the presence of non-smooth tumor margins and/or non-hypervascular HBP hypointense nodules, 5-year RFS in patients with high risk MR findings was significantly lower than in those without after both hepatic resection (31.1% vs. 74.2%, P<0.001, HR=3.56 [1.94-6.55]) and RFA (24.3% vs. 54.6%, P<0.001, HR=2.38 [1.62-3.51]).
Conclusions: Non-smooth tumor margins and the presence of non-hypervascular HBP hypointense nodules were demonstrated to be independent significant predictive factors of tumor recurrence after either hepatic resection or RFA.