Time to transplantation as a predictor of hepatocellular carcinoma recurrence after liver transplantation.

Abstract

In the United States, there are significant geographic disparities in the time to transplantation for patients with hepatocellular carcinoma (HCC); it is possible that rapid transplantation contributes to higher rates of posttransplant HCC recurrence because there is insufficient time for the tumor biology to manifest. In this study, we compared HCC recurrence in rapid transplant patients and their slower transplant counterparts. We identified adult liver transplantation (LT) candidates in the Organ Procurement and Transplantation Network/United Network for Organ Sharing (UNOS) data set who were granted an initial exception for an HCC diagnosis between January 1, 2006 and September 30, 2010 and underwent transplantation in the same time window. Patients were followed until HCC recurrence, non-HCC-related death, or last follow-up. The cumulative incidence of HCC recurrence was compared for patients waiting ≤ 120 days and patients waiting >120 days from an HCC exception to LT. The association between the risk of posttransplant recurrence and the wait time was further evaluated via competing risks regression with the Fine and Gray model. For 5002 LT recipients with HCC, the median wait time from an exception to LT was 77 days, and it varied from 30 to 169 days by UNOS region. The cumulative incidence of posttransplant HCC recurrence was 3.3% [95% confidence interval (CI) = 2.8%-3.8%] and 5.6% (95% CI = 5.0%-6.3%) within 1 and 2 years, respectively. The rate of observed recurrence within 1 year of transplantation was significantly lower for patients waiting >120 days versus patients waiting ≤ 120 days (2.2% versus 3.9%, P = 0.002); however, the difference did not persist at 2 years (5.0% versus 5.9%, P = 0.09). After we accounted for clinical factors, the HCC recurrence risk was reduced by 40% for patients waiting >120 days (subhazard ratio = 0.6, P = 0.005). In conclusion, the risk of HCC recurrence within the first year after transplantation may be lessened by the institution of a mandatory waiting time after an exception is granted.