Use of Livers With Fibrosis Based on Donor Hospital Biopsy: Missed Opportunities?

Abstract

Despite increases in the number of deceased donors in the United States, the donor supply fails to meet the ever-increasing demand. Centers have had to increase use of "marginal" liver grafts to increase the number of deceased donor liver transplantations (DDLTs). The term marginal has been used to describe donors with significant macrosteatosis, advanced age, donations after circulatory death, and split livers, for which a lot of data exist in the field of liver transplantation. (1) However, there are little data on use and outcomes of DDLTs from donors with fibrosis and none on a national level. A single-center study has shown the feasibility of transplanting livers with F1/F2 fibrosis per the Ishak scale, but there are knowledge gaps. In fact, some suggest that livers with greater than F2 fibrosis are unsuitable for transplantation. (2)(3)(4) Therefore, we sought to use national data to evaluate organ use and graft outcomes among donors with liver fibrosis. MethodsWe evaluated Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS) data from December 24, 2014, to June 11, 2020. The Standard Transplant Analysis and Research file included data on donor biopsies, including hepatic fibrosis. Liver fibrosis was graded using the Ishak scale and categorized as none/minimal (0-1), mild/ moderate (2-3), and advanced/cirrhotic (4-6). STATISTICAL ANALYSISThe following 2 analyses were performed: (1) multivariable logistic regression models and (2) mixedeffects Cox regression models. We included donor covariates that could be related to an increased risk of fibrosis, use, and/or early graft outcomes. Liver UseWe fit multivariable logistic regression models with the primary exposure of liver fibrosis. We used a backward selection process to include variables with a P value <0.05. Graft OutcomesWe fit time-to-event models with donor fibrosis as the primary exposure. We fit 3 models, truncating follow-up at 3, 6, and 12 months to focus on short-term graft failure. To account for correlated graft outcomes within transplant centers, we fit mixed-effects Cox regression models with center as a random effect. We

A contemporary analysis of 20,086 deceased donor liver biopsies

“…20 Furthermore, in a more contemporary national retrospective study of the OPTN/UNOS database, Narasimman et al also demonstrated no significant association between Ishak level of fibrosis and 3, 6, 12, 24, or 36 month graft survival. 12 High degrees of fatty infiltration, as indicated by ≥ 30% macrovesicular steatosis, however, have demonstrated varying results in portending worse recipient outcomes. This discrepancy is well known and has been discussed previously.…”

“…However, consensus has not been uniformly achieved. Specifically, previous studies have not uniformly agreed upon an association with the poorer 1‐year graft survival and high degrees (≥30%) of macrovesicular steatosis, 7,9,11 while relationships with fibrosis 12–14 and inflammation 15,16 identified on donor liver biopsy similarly remain unclear. Indeed, no systematic standard exists delineating which donors should receive biopsy, and the impact of biopsy findings remains provider dependent 17 …”

DCD Hepatitis C Virus–positive Donor Livers Can Achieve Favorable Outcomes With Liver Transplantation and Are Underutilized

“…11 Liver fibrosis on donor liver biopsy was assessed according to the Ishak score, which ranges from 0 to 6. 13,15 Significant liver fibrosis was defined as those with an Ishak score ≥3. 11 Macrosteatosis on donor liver biopsy was categorized as no (<5%), mild (5%–29%), moderate (30%–60%), and severe (≥60%).…”

“…12 Because biopsies are usually not performed until cross-clamp is achieved in DCD LT, the time allotted for obtaining a biopsy and awaiting its results prolongs cold ischemia time (CIT). Recently, Narasimman et al 13 reported that, although liver fibrosis on donor biopsy increased the rate of graft discard, it did not compromise transplant outcomes. Because of time constraints in DCD LT and the limited impact on transplant outcomes, the utility of biopsy on DCD LT warrants evaluation.…”

Procurement Liver Biopsies: More Scrutiny May Yield More Opportunities

“…In this most recent issue of Liver Transplantation , Narasimman et al examined liver biopsy data from the time of procurement in the United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research (STAR) file from December 24, 2014, to June 11, 2020, a period when roughly 45,000 liver transplantations were performed in the United States. ( 2 ) Biopsies were performed in 19,947 donors, and 15,130 of these livers (roughly one‐third of all liver transplantations performed) were transplanted. The remaining 4817 (24.1%) were discarded.…”