Value of microvascular invasion grade in predicting the early recurrence of hepatocellular carcinoma after radical hepatectomy

Objective To investigate the value of microvascular invasion(MVI) grade versus TNM stage and Barcelona Clinic Liver Cancer(BCLC) stage in predicting the early recurrence of hepatocellular carcinoma(HCC) after radical hepatectomy and the clinical value of MVI grade through a retrospective analysis of the prognosis of patients after HCC surgery.Methods A total of 100 HCC patients who underwent radical hepatectomy in Department of Hepatobiliary Surgery,The Second Affiliated Hospital of Kunming Medical University,from December2015 to December 2017 were enrolled,and according to the results of the 2-year follow-up,these patients were divided into recurrence group with 49 patients and non-recurrence group with 51 patients.Laboratory markers and MVI grade were compared between the two groups,and MVI grade,TNM stage,and BCLC stage were compared in terms of their value in predicting 2-year recurrence-free survival(RFS) after surgery.The t-test was used for comparison of normally distributed continuous data between groups,and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups;the chi-square test was used for comparison of non-ranked data between two groups,and the Mann-Whitney U test was used for comparison of ranked data between groups;the Kruskal-Wallis H test was used for comparison between three groups,and the Bonferroni method was used for further comparison between two groups.The Kaplan-Meier method was used to plot survival curves,and the log-rank test was used for survival analysis.The consistency index calculated by RMS package was used to compare the predictive value of clinicopathological staging systems.Results Compared with the non-recurrence group,the recurrence group had significantly higher alpha-fetoprotein level(Z=0.099,P<0.05) and proportion of patients with MVI(Z=-2.651,P=0.008).After 2 years of follow-up,there were 47 patients in M0 group,34 in M1 group,and 19 in M2 group;18 patients in the M0 group(38.3%),16 in the M1 group(47.1%),and 15 in the M2 group(78.9%) experienced recurrence,and there was a significant difference in recurrence between the three groups(H=8.934,P=0.011);further comparison between two groups showed that the M2 group had a significantly higher number of patients with recurrence than the M0 group and the M1 group(P<0.05).The cumulative recurrence rate was 41.9% in the M0 + M1 group and 78.9% in the M2 group,and there was a significant difference between these two groups(χ2=11.445,P<0.001);the M2 group had a significantly lower 2-year RFS rate than the M0 + M1 group.As for BCLC stage,the cumulative recurrence rate was 36.2% in the patients with early-stage(stage 0 + stage 1) HCC and 66.7% in those with middle-and late-stage(stage 2 + stage 3) HCC,and there was a significant difference between the two groups(χ2=5.047,P=0.012);the middle-and late-stage group had a significantly lower 2-year RFS rate than the early-stage group.As for TNM stage,the cumulative recurrence rate was 24.5% in the patients with stage Ⅰ HCC and 72.5% in those with stage Ⅱ + Ⅲ HCC,and there was a significant difference between the two groups(χ2=17.223,P<0.001);the stage Ⅱ + Ⅲ group had a significantly lower 2-year RFS rate than the stage I group.TNM stage had the highest value in predicting 2-year RFS,while MVI and BCLC stage had a similar predictive value(consistency index:0.659 vs 0.598 vs 0.600).Conclusion Compared with MVI patients with no risk or low risk,patients with high-risk MVI have a significantly higher probability of early recurrence,and thus MVI may become an evaluation target for postoperative treatment.