Alpha-fetoprotein: the predictor of microvascular invasion in solitary small hepatocellular carcinoma and criterion for anatomic or non-anatomic hepatic resection.

BACKGROUND/AIMS: This study aimed to identify the preoperative predictors of microvascular invasion (MVI) in solitary small hepatocellular carcinoma (HCC) and evaluate their application in surgical treatment. METHODOLOGY: We retrospectively analyzed 161 patients with solitary small HCC who underwent curative hepatic resection. Overall and disease-free survival rates were calculated by Kaplan-Meier method and compared by log-rank test. The independent predictors were identified by Cox proportional hazards model. RESULTS: MVI was an independent predictor of both overall and disease-free survival. In 51 patients with MVI, anatomic resection achieved better survival than non-anatomic resection. However, anatomic resection and non-anatomic resection brought similar survival in patients without MVI. Alpha-fetoprotein (AFP) was identified as the unique predictor of MVI (HR=2.773, p=0.004). Anatomic resection achieved better survival outcome than non-anatomic resection when AFP >100μg/L (5-year overall survival rate: 85% vs. 55%, p=0.024; 5-year disease-free survival rate: 37% vs. 21%, p=0.025), while there was no statistical survival difference between anatomic and non-anatomic resection when AFP 100μg/L.