Hypothesis: The clinical significance of hepatectomy for hepatocellular carcinoma (HCC) is still controversial because of frequent intrahepatic recurrence, which results from either recurrence due to residual intrahepatic metastasis (Rim) or recurrence due to metachronous, multicentric liver carcinogenesis (Rmc).
Design: Retrospective review. Disease-free survival curves were obtained by the Kaplan-Meier method and the rates of Rim and Rmc were analyzed using 2 regression lines, based on the evidence that Rmc occurs at a constant rate throughout follow-up, whereas Rim occurs only in the early postoperative period.
Setting: University hospital.
Patients: From 1980 to 1996, 241 patients with HCC who underwent curative hepatic resection.
Main outcome measure: Intrahepatic recurrence.
Results: Disease-free survival curves for all patients in the early (within 2 years) and late (4 years after surgery) follow-up were approximated by 2 regression lines, which represent both Rim and Rmc (Y(1) = -3.4X + 48) and only Rmc (Y(2) = -23.1X + 98). Using this approximation, the annual incidence of Rim within 2 years (a(1)-a(2)) was calculated as 19.7% and that of Rmc (a(2)) was 3.4%. The ratio of Rim in tumor recurrence (b(1)-b(2)) was 50%, and that of Rmc (b(1)) was 48%. The ratios of Rmc in patients with stages I and II HCC were 60% and 64%, respectively. In contrast, the values could not be calculated in patients with stages III and IVA because all but 2 patients showed recurrence within 4 years after surgery.
Conclusion: Tumor recurrence is estimated to result from metachronous liver carcinogenesis in 48% of hepatectomized patients with HCC.