Microvessel density in hepatocellular carcinoma: Prognostic significance and review of the previous published work

Aim: Assessment of the microvessel density (MVD) may yield important information leading to an effective antiangiogenic treatment for hepatocellular carcinoma (HCC). Methods: The intratumoral MVD of 136 HCC patients was retrospectively evaluated using CD34. The correlation between the MVD and clinicopathological findings was assessed. In addition, the prognostic factors influencing the 2-year disease-free survival (DFS) and overall survival (OS) were analyzed. Results: The MVD of each tumor size group (<2, 2-5 and >5cm) was 196±51, 181±63 and 147±69. The MVD of each histological grade (well-, moderately and poorly differentiated) was 200±56, 184±61 and 114±55. The optimum cut-off values of the MVD for the 2-year DFS and OS were 118.3 and 112.7, respectively. For the 2-year DFS, high tumor marker levels (α-fetoprotein >100ng/mL and protein induced by vitamin K absence/antagonist-II >100mAU/mL), poorly differentiated hepatocellular carcinoma (HCC), a high Ki-67 index (>20%), a large tumor size (>5cm), vascular invasion, high tumor-node-metastasis (TNM) stage (III/IV) and a low MVD were the significant unfavorable prognostic factors. For the OS, a high Ki-67 index, a large tumor size, vascular invasion, high TNM stage and a low MVD were the significant risk factors for death. By the multivariate analysis, a low MVD was identified as an independent predictor of the 2-year DFS as well as the OS. Conclusion: A low MVD can be used to predict an unfavorable prognosis in HCC patients.