Background: Although extrahepatic metastasis occurs rarely after hepatic resection for hepatocellular carcinoma (HCC), the prognosis of these patients is extremely poor. Predictors of extrahepatic metastasis have not been fully investigated.
Methods: To identify predictors of extrahepatic metastasis after resection, we retrospectively investigated 77 patients with HCC tumors > 50 mm in diameter who underwent hepatic resection. We investigated correlations between postoperative extrahepatic metastasis and clinicopathologic factors as well as extrahepatic metastasis-free survival rate by log rank test and predictors of extrahepatic metastasis by univariate and multivariate logistic regression models.
Results: Hepatitis B surface antigen (HBs-Ag) was found in 25 (32.5%) of 77 patients, and extrahepatic metastasis occurred in 26 (33.8%). Patients with extrahepatic metastasis showed better liver function and a high occurrence of HBs-Ag positivity than those without. The 5-year extrahepatic metastasis-free survival rate was worse in patients with HBs-Ag positivity, larger tumors (> or = 70 mm), higher alfa-fetoprotein level (> or = 300 ng/mL), and lower indocyanine green retention rate at 15 minutes (ICGR15) (< 15%) than in those without. By univariate logistic regression analysis, HBs-Ag positivity, larger HCC tumor (> or = 70 mm), lower ICGR15 (< 15%), and lower preoperative lymphocyte count (< 1000/mm3) were predictors of extrahepatic metastasis (P < .1). By multivariate analysis, HBs-Ag positivity was an independent predictor of postoperative extrahepatic metastasis (P = .04).
Conclusions: In patients positive for HBs-Ag, radiologic examination of extrahepatic organs should be performed as a part of the postoperative surveillance. Hepatitis B virus infection may promote establishment of extrahepatic metastasis.