Background: A majority of patients with hepatocellular carcinoma (HCC) undergoing liver transplantation (LT) meet the Milan criteria, but these are still regarded as the narrowest criteria for transplantation. Prognostic analysis of incidentally detected HCC after LT suggests that a subgroup of HCC patients is at very low risk of recurrence. To determine the criteria defining this super-selection group, we retrospectively analyzed survival data of 593 adult living-donor LT recipients with HCC in the explanted liver
Discussion: Tumor features of incidental HCC in 38 patients not showing recurrence were analyzed. Of these patients, 34 (89.5%) each had ≤2 tumors and tumors ≤2.0 cm in size. Applying these criteria to 555 patients with pretransplant known HCC (pkHCC) allowed us to identify 79 patients with untreated pkHCCs ≤2.0 cm in size. To date, only two of these patients have shown recurrence, making the conditions for super-selection the presence of tumors ≤2.0 cm in size, ≤2 tumors, alpha-fetoprotein ≤200 ng/mL, and no pretransplant treatment. In 87 patients satisfying these criteria, the 10-year recurrence and survival rates were 1.3% and 92.1%, respectively. After excluding patients meeting these criteria, the 5-year recurrence rates in patients satisfying the Milan, University of California at San Francisco, and Asan criteria were increased by 2.9-4.0%. In conclusion, this super-selection or super-Milan category may be used for validation assessment of various indication criteria and for the development of cost-effective post-transplantation HCC surveillance protocols. Further studies should be followed for deceased-donor LT and patients who have undergone pretransplant treatment.