Comparison of Wait-List Mortality Between Cholangiocarcinoma and Hepatocellular Carcinoma Liver Transplant Candidates.

Abstract

Despite the divergent disease biology of cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC), wait-list prioritization is identical for both diagnoses. We compared wait-list and posttransplant outcomes between CCA and HCC liver transplantation patients with Model for End-Stage Liver Disease exceptions using Scientific Registry of Transplant Recipients data. The 408 CCA candidates listed between 2003 and mid-2017 were matched to 2 HCC cohorts by listing date (±2months, n=816) and by Organ Procurement and Transplantation Network (OPTN) region and date (±6 months, n=408). Cumulative incidence competing risk regression examined the effects of diagnosis, OPTN region, and center-level CCA listing volume on wait-list removal due to death/being too ill (dropout). Cox models evaluated the effects of diagnosis, OPTN region, center-level CCA volume, and waiting time on graft failure among deceased donor liver transplantation (DDLT) recipients. After adjusting for OPTN region and CCA listing volume (all P≥0.07), both HCC cohorts had a reduced likelihood of wait-list dropout compared with CCA candidates (HCC with period matching only: subdistribution hazard ratio [SHR]=0.63; 95% CI, 0.43-0.93; P=0.02 and HCC with OPTN region and period matching: SHR=0.60; 95% CI, 0.41-0.87; P=0.007). The cumulative incidence rates of wait-list dropout at 6 and 12 months were 13.2% (95% CI, 10.0%-17.0%) and 23.9% (95% CI, 20.0%-29.0%) for CCA candidates, 7.3% (95% CI, 5.0%-10.0%) and 12.7% (95% CI, 10.0%-17.0%) for HCC candidates with region and listing date matching, and 7.1% (95% CI, 5.0%-9.0%) and 12.6% (95% CI, 10.0%-15.0%) for HCC candidates with listing date matching only. Additionally, HCC DDLT recipients had a 57% reduced risk of graft failure compared with CCA recipients (P<0.001). Waiting time was unrelated to graft failure (P=0.57), and there was no waiting time by diagnosis cohort interaction effect (P=0.47). When identically prioritized, LT candidates with CCA have increased wait-list dropout compared with those with HCC. More granular data are necessary to discern ways to mitigate this wait-list disadvantage and improve survival for patients with CCA.