Systematic Evaluation of the Safety Threshold for Allograft Macrovesicular Steatosis in Cadaveric Liver Transplantation

Abstract

Background: Currently, 30% macrovesicular steatosis (MaS) content is usually assigned empirically as the boundary between “use” and “refuse” a donor liver for liver transplantation (LT); however, this cut-off is questionable due to the lack of systemic evidence of the efficiency relative to prognosis prediction. Clinicians have tried to identify the threshold for optimized utilization of marginal steatotic allografts, but controversy exists among different studies. Aim: Our study aimed to systematically determine an acceptable donor MaS content cut-off without incurring extra risk in liver transplantation, using meta-analysis. Methods: The relevant literature reporting the relationship between MaS content and post-transplant mortality/morbidity was searched and retrieved in Pubmed, Embase, and ISI Web of Science. Results: Nine studies were enrolled into the final analysis. A categorical comparison revealed that patients who received allografts with moderate steatosis (MaS content >30%) had significantly higher risks of graft failure/dysfunction, but not of mortality. Dose-response analysis showed that donor MaS content affected the graft failure/dysfunction in a non-linear relationship. Risks associated with MaS content in terms of poorer outcomes were independent of other risk covariates for liver transplantation. A non-significant increase in risk of inferior post-transplant outcomes was observed in patients who received allografts with a MaS content <35%. The risks of post-transplant graft failure and dysfunction increased with severe donor MaS content infiltration, without a consistent relationship. Conclusions: The threshold of allograft MaS content can be safely extended to 35% without additional risk burden on post-transplant inferior outcomes. Clarification on “the effects of stratification” for MaS content can provide theoretical evidence for further optimal utilization of marginal steatotic allografts in liver transplantation.

Impact of living donor liver with steatosis and idiopathic portal inflammation on clinical outcomes in pediatric liver transplantation: Beijing experience

“…Assessing the degree of donor hepatic steatosis is one important histological evaluation (8)(9)(10)(11). Although mild macrovesicular steatosis (up to 30%) does not adversely affect recipients' outcomes in adult whole-liver LTs (11)(12)(13)(14) and is also believed to have no adverse effects on clinical outcome of LDLT recipients, there is a need to study this concept in detail in LDLT.…”

Clear mortality gap caused by graft macrosteatosis in Chinese patients after cadaveric liver transplantation

“…Analysis on dose-response relationship was conducted by two-stage random effects model (25). Risk curves fitting and linearity test was evaluated by STATA software (release 14) according to method described before (16).…”

“…Graft steatosis is a quantitative covariate, which can't be simply used to define the boundary between "absolute" acceptance or unacceptance for LT. "Dose-response" risk-effect model seemed more reasonable to present the interrelationship between donor steatosis and posttransplant outcomes (16). However, the continuous risk of graft steatosis on post-transplant prognosis was less discussed in a fixed cohort before.…”

Computed Tomography-Based Radiomic Analysis for Preoperatively Predicting the Macrovesicular Steatosis Grade in Cadaveric Donor Liver Transplantation

“…From a pathological perspective, steatosis can be categorized into microvesicular, macrovesicular, and mixed forms. We have focused on macrovesicular steatosis (MaS) in this study because it is a major cause of graft failure in donor livers [ 6 ]. The use of grafts with mild steatosis (MaS content < 30%) is safe; however, grafts with moderate-to-severe steatosis (MaS content > 30%) are not recommended for use.…”