To evaluate the prognostic value of pathological characteristics of microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC).

289 consecutive HCC patients who underwent curative hepatectomy at Nanjing Drum Tower Hospital from January 2007 to December 2015 were retrospectively studied. These patients were divided into three groups: the no-MVI group (n=176), the low-MVI group (the number of invaded microvessels ≤ 5 and the distance of invasion ≤ 1 cm, n=53) and the high-MVI group (the number of invaded microvessels >5 or the distance of invasion >1 cm, n=60). The clinical and pathological data and the survival outcomes of these HCC patients were analyzed. We further compared the prognosis among the three groups.

Kaplan-Meier survival indicated that the number of invaded microvessels > 5 and the distance of invasion > 1 cm were associated with cumulative and recurrence-free survival rates of HCC patients. The cumulative and recurrence-free survival rates of the high-MVI group were significantly poorer than those of the low-MVI and the no-MVI groups. Multivariate analysis showed ICG-R15 (HR=1.049, 95%CI: 1.002~1.097), tumor size (HR=1.138, 95%CI: 1.043~1.241), and high-MVI (HR=3.245, 95%CI: 1.946~5.413) were independent risk factors for cumulative survival. Tumor size (HR=1.117, 95%CI: 1.050~1.188), and high-MVI (HR=2.222, 95%CI: 1.540~3.205) were independent risk factors for recurrence-free survival. The prognosis of the no-MVI and low-MVI groups were significantly better than the high-MVI group (P<0.05). The recurrence rates of the low-MVI and no-MVI groups (49.4% and 67.9%) were significantly lower than the high-MVI group (80.0%, P<0.05).

The risk classification of MVI based on histopathological features was valuable in predicting prognosis of HCC patients. We could use the risk classification of MVI to establish a follow-up and individualized treatment plan for HCC patients.

Carcinoma, hepatocellular; Prognosis; Pathologic classification; Microvascular invasion