Hughes, Dempsey L.

Introduction: Liver transplantation (LT) provides significant survival benefits to patients with unresectable HCC. In the United States, organ allocation policies for HCCs within the United Network for Organ Sharing criteria do not prioritize patients based on their differences in oncological characteristics. This study assessed whether transplant-associated survival benefits (TASBs) vary among patients with different tumor burden scores (TBS) measured at the time of listing. Methods: We analyzed data from adults applying for HCC MELD exception points between 2002 and 2019, with follow-up until December 2023, using the Scientific Registry of Transplant Recipients. TBS was determined based on the largest tumor diameter and number of HCCs. Patients were categorized into low (≤3), intermediate (3.1–5), and high (>5) TBS groups. TASB was measured as the difference in 5-year survival with and without LT. Results: This study included 36,634 LT candidates. High-TBS patients had higher waitlist dropout rates and marginally lower post-transplant survival, resulting in a significantly greater TASB. The 5-year TASB for the low, intermediate, and high TBS groups were 15.7, 22.1, and 25.0 months, respectively. The adjusted survival benefit expressed in 5-year survival differences was 21.9%, 34.5%, and 39.4% in the low, intermediate, and high TBS groups, respectively ( p <0.001). Conclusions: Higher TBS during listing correlates with greater LT benefits for patients with unresectable HCC within UNOS criteria. We conclude that organ allocation policies in the United States should prioritize patients with high TBS due to their increased risk of dropout and comparable post-transplant survival when compared to patients with less advanced tumors.

Background. Cardiovascular disease and physical decline are prevalent and associated with morbidity/mortality in liver transplant (LT) patients. Cardiopulmonary exercise testing (CPX) provides comprehensive cardiopulmonary and exercise response assessments. We investigated cardiorespiratory fitness (CRF) and cardiac stress generated during CPX in LT candidates. Methods. LT candidates at 2 centers underwent CPX. Standard-of-care cardiac stress testing (dobutamine stress echocardiography, DSE) results were recorded. Physical function was assessed with liver frailty index and 6-min walk test. CPX/DSE double products were calculated to quantify cardiac stress. To better study the association of CPX-derived metrics with physical function, the cohort was divided into 2 groups based on 6-min walk test median (372 m). Results. Fifty-four participants (62 ± 8 y; 65% men, Model for End-Stage Liver Disease-Na 14 [10–18]) underwent CPX. Peak oxygen consumption was 14.1 mL/kg/min for an anerobic threshold of 10.2 mL/kg/min, with further CRF decline in the lower 6MWT cohort despite lack of liver frailty index-frailty in 90%. DSE was nondiagnostic in 18% versus 4% of CPX (P = 0.058). All CPX were negative for ischemia. A double product of ≥25 000 was observed in 32% of CPX and 11% of DSE (P = 0.020). Respiratory function testing was normal. No patient presented major cardiovascular events at 30 d post-LT. Conclusions. CPX provided efficient and effective combined cardiopulmonary risk and frailty assessments of LT candidates in a 1-stop test. The CRF was found to be very low despite preserved physical function or lack of frailty.