Conditional Survival Analysis Demonstrates that Recurrence Risk of Surgically Treated Hepatocellular Carcinoma Evolves with Time

OBJECTIVE: The study aim was to investigate long-term change in tumor recurrence risk in patients with hepatocellular carcinoma (HCC) after hepatic resection. Recurrence probability over time was estimated by conditional survival (CS) analysis. PATIENTS AND METHODS: Early-stage HCC patients with hepatic resection were selected for inclusion from our surgery database. Variables predictive of tumor recurrence were identified by univariate and multivariate analyses. Five-year recurrence-free CS probability was calculated for all patients and for risk groups stratified by independent predictors. RESULTS: In this series of 436 patients, tumor size >5 cm, microvascular invasion, positive resection margin, liver cirrhosis, and a indocyanine green retention ratio at 15 min (ICG-R15) >20% were independently predictive of tumor recurrence. The estimated 5-year recurrence-free CS probability improved with each additional year of recurrence-free survival, and the improvement was significantly greater in the high-risk than in the low- or intermediate-risk groups. CONCLUSION: CS provides added value during follow-up of early-stage HCC patients treated by surgical resection.