Predictors of microvascular invasion before hepatectomy for hepatocellular carcinoma

BACKGROUND AND OBJECTIVES: Microvascular invasion (MVI) is difficult to detect before resection of hepatocellular carcinoma (HCC). METHODS: Clinicopathological and outcome data were retrospectively compared between 213 HCC patients with MVI and 221 patients without MVI who underwent hepatectomy. RESULTS: MVI risk was selected as an independent prognostic indicator for both disease-free and overall survival in our 434 HCC patients. Univariate and multivariate analyses showed that an age under 65 years, a protein induced by vitamin K absence/antagonism II (PIVKA-II) level ≥200 mAU/ml, a preoperative tumor size ≥5.0 cm, and poorly differentiated carcinoma were independent predictors of MVI. When age, PIVKA-II level, and tumor size (data available before surgery) were scored as a combined index, the total score demonstrated a significant correlation with the extent of vascular invasion and with survival after hepatic resection. CONCLUSIONS: An age under 65 years, increase of PIVKA-II, and larger tumor size were preoperative predictors of MVI in HCC patients undergoing potentially curative resection. Our combined score based on the age, serum PIVKA-II, and preoperative tumor size is a reliable predictor of MVI and survival in patients with HCC.