The prognostic value of microvascular invasion in early-intermediate stage hepatocelluar carcinoma: a propensity score matching analysis

Background: Microvascular invasion (MVI) is well established as a negative prognostic factor for hepatocelluar carcinoma (HCC). However, its prognostic value in different subgroups of Barcelona Clinical Liver Cancer (BCLC) stages remains to be elucidated. Methods: Four hundred fifty-eight MVI-negative and 204 MVI-positive patients who underwent hepatectomy were retrospectively analyzed. After propensity score matching (PSM) analysis, 187 pairs of matched patients were generated. Long-term survival was compared by the Kaplan-Meier method. Results: Patients with MVI commonly had more advanced tumors. All the patients with MVI had significantly worse survival rate compared to the patients without MVI before and after PSM(p < 0.001). In the subgroup analysis, BCLC stage A HCC patients without MVI had better prognosis than those with MVI before and after PSM (p < 0.001 and p = 0.024). For BCLC stage B HCCs, long-term survival was significantly better for patients without MVI before PSM(p = 0.001). However, the overall survival (OS) rate was comparable between both groups after PSM (p = 0.682), although MVI-positive group had a higher rate of recurrence (p = 0.011).. Surgery type, satellite lesions, tumor size, and serum ALT level were statistically significant factors associated with survival in MVI-positive group. Tumor number, tumor size and neutrophil to lymphocyte ratio (NLR) were predictors of survival in MVI-negative group. Conclusions: Its prognostic value in different subgroups of BCLC stages differed. MVI is an independent predictor of prognosis in patients with BCLC stage A. For BCLC stage B HCCs, MVI-positive group had poor prognosis through more advanced HCCs.