ABSTRACT
Objective:To evaluate the effect of microvascular invasion (MVI) on postoperative prognosis of microhepatocellular carcinoma by a meta-analysis system.Methods:Relevant literatures in PubMed, Cochrane Library, Embase, CNKI, VIP and Wanfang databases were systematically searched. The search period was from January 2012 to January 2022. The Chinese search terms were "liver cancer" , "hepatocellular carcinoma" , "2 cm" , "microvascular invasion" , and "prognosis" . The English search terms were "small" , "solitary small" , "up to 2 cm" , "< 2 cm" , "liver" , "hepatocellular carcinoma" , "microvascular invasion" . The differences in prognosis of patients with microhepatocellular carcinoma in MVI(+ ) group and MVI(-) group were compared. Meta-analysis was performed using Review Manager 5.4 software.Results:Finally, 7 articles were included in the systematic review, with a total of 1 319 patients. All included literatures were scored ≥7 on the modified Newcastle-Ottawa scale. The results of meta-analysis showed that there were no significant differences in 1-year overall survival (OS) between MVI(+ ) group and MVI(-) group ( OR=3.14, 95% CI: 0.92-10.72, P=0.068). The 5-year OS time of patients in the MVI(+ ) group was shorter than that in the MVI(-) group, and the differences were statistically significant ( OR=2.34, 95% CI: 1.62-3.36, P<0.001). The 1-year and 5-year disease-free survival of the MVI(-) group were better than those of the MVI(+ ) group, and the difference was statistically significant (1-year: OR=3.09, 95% CI: 1.75-5.44, P<0.001; 5 years: OR=1.76, 95% CI: 1.24-2.51, P=0.002). Conclusion:The 5-year and long-term survival of MVI(+ ) patients with microhepatocellular carcinoma was poor, and the postoperative recurrence rate was high.