Prognostic value and preoperative predictors of microvascular invasion in solitary hepatocellular carcinoma ≤ 5 cm without macrovascular invasion

OBJECTIVES: The aim of this study was to investigate the prognostic value and preoperative predictors of microvascular invasion (MVI) in solitary hepatocellular carcinoma (HCC) ≤ 5 cm without macrovascular invasion. METHODS: A total of 233 consecutive HCC patients underwent curative hepatectomy were included in our study. Independent risk factors influencing the prognosis were identified, and preoperative predictors for MVI were determined. RESULTS: Multivariate regression analysis identified ICG-R15, BCLC staging and MVI as independent risk factors for the overall survival rate. Type of resection and MVI were independent risk factors for the recurrence-free survival rate. Kaplan-Meier analysis showed the overall survival and recurrence-free survival rates in patients with MVI were significantly poorer than those in patients without MVI (P = 0.002 and P = 0.001). Anatomical resection obviously improved the overall survival and recurrence-free survival rates in patients with MVI compared with non-anatomical resection (P = 0.017 and P = 0.009). A prediction scoring system for MVI was built up according to the three independent predictors (tumor size > 3.5 cm, AFP > 200 ng/mL and GGT > 53 U/L). The prevalence of MVI in HCC patients with predictive score ≥ 2 was 58.3%, which was obviously higher than patients with predictive score < 2 (20.8%). CONCLUSIONS: MVI is associated with a poor prognosis in solitary HCC ≤ 5 cm after hepatectomy. Anatomical resection could improve the prognosis of HCC patients with MVI. The preoperative prediction scoring model has practical value for the prediction of MVI.