Recipient-Donor Sex Constellation in Liver Transplantation for Hepatocellular Carcinoma-An ELTR Study.

Background & Aims Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Liver transplantation (LT) is a curative treatment option. We investigated survival outcomes based on recipient-donor sex constellation (RDSC) following LT.Methods We performed a European Liver Transplant Registry analysis, including patients from 1988 to December 2022. The cohort was split into four RDSC groups: female donor female recipient (FDFR), female donor male recipient (FDMR), male donor female recipient (MDFR) and male donor male recipient (MDMR). Survival analysis, including death with recurrence, was performed.Results In 7601 LT for HCC with an overall median follow-up of 22.6 months (5.8, 60.7), death was registered in 25.1% and, as primary cause of death, HCC tumour recurrence in 26.0%. There was no statistically significant difference on crude survival estimates among the different RDSC groups (log-rank p = 0.66) with 10-year overall survival (OS) of 54.5% in FDFR, 54.6% in FDMR, 59.1% in MDFR and 56.9% in MDMR. On multivariable analysis, RDSC showed a significant effect on OS (FDFR as reference): MDFR (aHR 0.72, p = 0.023). No significant difference was found for FDMR (aHR 0.98, p = 0.821) and MDMR (aHR 0.90, p= 0.288). Regarding overall registered causes of death, differences between RDSC groups were found in rejection (p = 0.017) and cardiovascular (p = 0.046) associated deaths.Conclusions In female recipients undergoing LT for HCC, male donor grafts were associated with a 28% reduction of mortality compared to female donor grafts.