Impact of human T-cell leukemia virus type 1 on living donor liver transplantation: a multi-center study in Japan

Background: The natural history of human T-cell leukemia virus type 1 (HTLV-1), which causes adult T-cell leukemia (ATL) or HTLV-1 associated myelopathy, after liver transplantation is unclear. Methods: We conducted a nationwide survey to investigate the impact of HTLV-1 status on living donor liver transplantation (LDLT) in Japan. We analyzed the cases of 82 HTLV-1-positive recipients and six HTLV-1-negative-before-LDLT recipients who received a hepatic graft from HTLV-1-positive donors. Results: Adult T-cell leukemia developed in five recipients who ultimately died. Of these five, two received grafts from HTLV-1-positive donors and three from HTLV-1-negative donors. The 1-, 3-, and 5-year ATL development rates were 4.5%, 6.5%, and 9.2%, respectively. Fulminant hepatic failure as a pre-transplant diagnosis was identified as an independent risk factor for ATL development (P = 0.001). The 1-, 3-, and 5-year survival rates for HTLV-1-positive recipients who received grafts from HTLV-1-negative donors were 79.9%, 66.1%, and 66.1%, and from HTLV-1-positive donors were 83.3%, 83.3%, and 60.8%, respectively. The 1-year survival rate for HTLV-1-negative recipients who received grafts from HTLV-1-positive donors was 33.3%. Conclusions: Fulminant hepatic failure is an independent risk factor for ATL development in HTLV-1-positive recipients. Grafts from HTLV-1-positive living donors can be transplanted into selected patients.