Immunosuppression and Long-term Survival After Single Living-donor Lobar Lung Transplantation From the Same Donor as Prior Hematopoietic Stem Cell Transplantation: An All-Japan Study

BACKGROUND: Single living-donor lobar lung transplantation (LDLLT) from the same donor as prior hematopoietic stem cell transplantation (HSCT) represents a unique immunologic setting because of donor-cell chimerism. However, data regarding immunosuppressive management and long-term outcomes in this setting remain limited. METHODS: We conducted a retrospective multicenter observational study of all patients in Japan who underwent single LDLLT from the same donor as in their prior HSCT. Between November 2006 and December 2024, 9 patients underwent this procedure at 5 centers. RESULTS: All recipients received immunosuppressive therapy for at least 3 mo after LDLLT. During follow-up, immunosuppression was successfully discontinued in 3 patients, whereas the remaining 6 were maintained on individualized reduced-dose maintenance immunosuppression. One patient died 39 mo after LDLLT, with respiratory dysfunction presumed to be associated with severe malnutrition. At a median follow-up of 154 mo for the entire cohort, 8 patients were alive with acceptable graft function. CONCLUSIONS: In this highly selected case series, acceptable long-term survival was observed after single LDLLT from the same donor as prior HSCT under reduced immunosuppression, and immunosuppression was successfully withdrawn in 3 patients.