Portal venous invasion: The single most independent risk factor for immediate postoperative recurrence of hepatocellular carcinoma

Background and Aim: Despite improvements of treatment in hepatocellular carcinoma (HCC), the recurrence rate after curative hepatic resection still remains remarkably high. An immediate recurrence of HCC after surgery is frustrating. We tried to clarify risks of immediate postoperative recurrence of HCC; that is, within 4 months after curative hepatic resection. Methods: A total of 167 patients with HCC underwent hepatic resection; 60 had immediate postoperative recurrences (IPR group), and 107 had disease-free survival for more than 5 years (DFS group). Variables were compared between the two groups. Results: Univariate analysis showed the following variables were significant risk factors for immediate postoperative recurrence of HCC: male sex, elevated serum aspartate aminotransferase level, greater amount of blood loss, longer operation time, worse tumor differentiation, higher tumor node metastasis stage, and presence of any of the following: intrahepatic metastasis, tumor-rupture, portal venous invasion, or microvascular invasion. In multivariate analysis, only portal venous invasion was a significant risk factor (odds ratio = 3.2, P = 0.03, standard error = 0.5, Logistic regression analysis). Conclusions: Portal venous invasion may be the most significant risk factor for immediate postoperative recurrence of HCC. However, accurate assessment of this risk factor may require histological examination, limiting its utility as a preoperative predictor. Further research is necessary to definitively identify preoperative predictors.