Outcomes and predictors of microvascular invasion of solitary hepatocellular carcinoma

Abstract

Microvascular invasion (MVI) is an important risk factor for early recurrence of hepatocellular carcinoma (HCC), but preoperative prediction of MVI is difficult. A retrospective review was undertaken on 167 patients with primary solitary HCC who underwent initial hepatectomy. Independent predictors of MVI were identified, and factors affecting disease-free survival in patients with MVI were clarified. Of the 167 patients, 20 patients (12%) had MVI. Recurrence rates of HCC after hepatectomy in MVI patients were significantly worse than in patients without MVI (P < 0.0361). Univariate analysis revealed that positive L3-AFP, PIVKA-II ≥ 150 mAU/mL and tumor size ≥3 cm preoperatively were associated with positive MVI. On multivariate analysis, independent predictors of MVI were PIVKA-II ≥ 150 mAU/mL (odds ratio [OR], 5.19; 95% confidence interval [95% CI], 1.44-24.87; P = 0.0109) and positive L3-AFP (OR, 3.47; 95% CI, 1.19-10.75; P = 0.0229). Among the MVI-positive group, the 1-, 2- and 3-year disease-free survival rates were 78%, 58%, and 58% in patients with surgical margin (SM) ≥ 10 mm and 38%, 29%, and 29% in those with SM < 10 mm, respectively (P = 0.0263). Patients with PIVKA-II ≥ 150 mAU/mL and positive L3-AFP on preoperative examination are at high risk for MVI.