Deceased-Donor Liver Size and the Sex-Based Disparity in Liver Transplantation

In deceased-donor liver transplantation, small- and large-for-size transplants are associated with elevated risk of graft loss.1 Despite this, deceased-donor liver offers are made without regard to size matching. Additionally, the deceased donor pool is 59% male, and thus female candidates might face more size-inappropriate offers than male candidates. We aimed to characterize the relationship between the volumes of offered deceased-donor livers and the liver volume needed to treat each candidate's liver disease. Using Scientific Registry of Transplant Recipients data, we calculated estimated liver volume (eLV) for each offered and accepted liver and eLV needed for each candidate (candidate need). We used the equation developed by Johnson et al,2 based on body surface area: Median eLV among female candidates was lower than eLV among male candidates (Figure 1, P < 0.001). Median eLV of livers offered to both female and male candidates was clinically similar (blue dashed lines). Median eLV of livers offered to female candidates was larger than female candidates' need (P < 0.001), and median eLV of livers offered to male candidates was smaller than the male candidates' need (P < 0.001). Women accepted livers from a narrower distribution and of a smaller eLV than that which they were offered (red dotted lines, P < 0.001). Men accepted livers from a similar distribution to that which they were offered (P = 0.3). The difference between eLV of offered livers and eLV that female and male candidates require might explain disparities in liver offer acceptance.3,4 Incorporating size-matching in deceased-donor allocation might reduce sex disparities driven by inappropriately sized offers.FIGURE 1: eLV of livers that female and male candidates need to treat their end-stage liver disease, of livers offered to female and male candidates, and of livers accepted by female and male candidates; 2010 to 2015.