Liver transplant recipient survival benefit with living donation in the model for endstage liver disease allocation era

Abstract

Receipt of a living donor liver transplant (LDLT) has been associated with improved survival compared with waiting for a deceased donor liver transplant (DDLT). However, the survival benefit of liver transplant has been questioned for candidates with Model for Endstage Liver Disease (MELD) scores <15, and the survival advantage of LDLT has not been demonstrated during the MELD allocation era, especially for low MELD patients. Transplant candidates enrolled in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study after February 28, 2002 were followed for a median of 4.6 years. Starting at the time of presentation of the first potential living donor, mortality for LDLT recipients was compared to mortality for patients who remained on the waiting list or received DDLT (no LDLT group) according to categories of MELD score (<15 or ≥ 15) and diagnosis of hepatocellular carcinoma (HCC). Of 868 potential LDLT recipients (453 with MELD <15; 415 with MELD ≥ 15 at entry), 712 underwent transplantation (406 LDLT; 306 DDLT), 83 died without transplant, and 73 were alive without transplant at last follow-up. Overall, LDLT recipients had 56% lower mortality (hazard ratio [HR] = 0.44, 95% confidence interval [CI] 0.32-0.60; P < 0.0001). Among candidates without HCC, mortality benefit was seen both with MELD <15 (HR = 0.39; P = 0.0003) and MELD ≥ 15 (HR = 0.42; P = 0.0006). Among candidates with HCC, a benefit of LDLT was not seen for MELD <15 (HR = 0.82, P = 0.65) but was seen for MELD ≥ 15 (HR = 0.29, P = 0.043).

Conclusion: Across the range of MELD scores, patients without HCC derived a significant survival benefit when undergoing LDLT rather than waiting for DDLT in the MELD liver allocation era. Low MELD candidates with HCC may not benefit from LDLT.

Figure 1

Outcomes of A2ALL transplant candidates. The probability of LDLT, DDLT, death on the waitlist or remaining alive without transplant over five years after first donor evaluation for living donor candidates with a) MELD<15 at evaluation and b) MELD15+ at evaluation. Estimates are based on the cumulative incidence function.

Figure 2

Mortality for transplant candidates. Mortality following initial potential donor evaluation for candidates without HCC according to MELD score at evaluation and whether LDLT was performed or not. For graphical purposes, mortality while awaiting LDLT is assumed to be the same as mortality for candidates for whom LDLT was not available up until the median time for LDLT (3.0 months for MELD<15 and 2.5 months for MELD15+). Shown for patient age=50, no HCC, with HCV, no other cholestatic disease, and MELD=10 at enrollment for MELD<15 group and MELD=20 at enrollment for MELD 15+ group.