Prognostic analysis of postoperative pathological microvascular invasion in hepatocellular carcinoma and the effect of surgical margin on prognosis.

Abstract

52 Background: To analyze the impact of different MVI grades and surgical margins on patient survival through analyzing the presence of microvascular invasion (MVI) after liver resection of hepatocellular carcinoma (HCC). Methods: The clinical and follow-up data of 513 HCC patients who underwent hepatectomy in our department from January 2016 to December 2020 were analyzed retrospectively. All the patients signed the informed consent form, complying with the medical ethics regulations. Risk factors of MVI in patients with HCC were analyzed by univariate and multivariate analysis, and effect of different MVI grades on postoperative complications was explored. The effects of different MVI grades and different surgical margins on tumor-free survival and overall survival were also analyzed. Results: There were 332 cases in M0 group, 123 cases in M1 group and 58 cases in M2 group. Univariate analysis showed that tumor diameter, tumor number, CNCL stage and alpha-fetoprotein were risk factors for MVI in patients with HCC, and multivariate analysis showed that tumor maximum diameter, tumor number and CNLC stage were independent influencing factors for MVI. There was no significant difference in the incidence of postoperative complications among different groups. The 1-year, 2-year, 3-year disease-free survival rate of M0 group was 79.6%, 71.0%, 63.4%, which was significantly higher than that in M1 group (59.6%, 48.0%，43.3%) and M2 group (31.0%, 27.5%, 25.2%). The 1-year, 2-year, 3-year overall survival rate of M0 group was 97.3%, 88.2%, 84.6%, which was significantly higher than that in M1 group (87.0%, 71.5%, 66.1%), and M2 group (79.3%, 61.9%, 52.6%),respectively. In the aspect of surgical margin, in MVI negative group, the disease-free survival rate of wide margin resection for 1-year, 2-year, 3-year was 82.6%, 70.7%, 65.4%, while that of narrow margin resection was 79.4%, 64.7% and 60.5% (p=0.322).The 1-year, 2-year, 3-year overall survival rate of patients who received wide margin resection was 97.5%, 89.6%, 85.2%, while that of patients who received narrow margin resection was 97.1%, 86.0%，82.8%. (p= 0.822). In the MVI positive group, the 1-year, 2-year and 3-year disease-free survival rate was 58.1%, 45.4%, 40.3% in the wide margin group and 42.9%, 37.3%, 36.1% in the narrow margin group (p=0. 044). The 1-year, 2-year, 3-year overall survival rate of the wide margin group was 88.8%, 71.9%, 64.3%, which was higher than that of the narrow margin group, 82.6%, 64.8%, 61.0% (p = 0.032). Conclusions: Tumor size, number and stage are independent risk factors for MVI positive patients.The higher the MVI grade, the worse the prognosis.In patients with MVI, the long-term prognosis of patients with wide margin is better than that of patients with narrow margin. Therefore, for patients with high risk of MVI before operation, wide margin should be selected as far as possible.