Roles and practice of living-related lobar lung transplantation

Living-donor lobar lung transplantation (LDLLT) was first performed in the USA and thereafter it was introduced in Japan in 1998 as an alternative modality to brain-dead donor lung transplantation (BDLT). Although the LDLLT procedure was employed for rapidly deteriorating patients who were hospitalized and mechanically ventilated at the time of transplantation, LDLLT demonstrated better or comparable post-transplant outcomes in comparison to BDLT. Less injured lobar grafts and a significantly shorter graft ischemic time possibly contributed to a significantly lower incidence of severe primary graft dysfunction (PGD) after LDLLT in comparison to BDLT. In standard LDLLT, patients obtained lobar grafts from two different donors, and thus most patients developed chronic lung allograft dysfunction (CLAD) only in the unilateral lung graft. This indicates that the contralateral unaffected lung graft could reserve lung function after the unilateral development of CLAD. In our transplant program, the incidence of CLAD per donor in LDLLT (14.4%) was also significantly lower in comparison to BDLT (24.7%). The 1-, 5- and 10-year survival rates after LDLLT were 90.9%, 75.5% and 57.2%, respectively, which were equivalent to those after BDLT (92.9%, 73.4% and 62.2%). The inherent surgical risk to the living donors should always be considered. In our experience, living-donor surgery was associated with a complication rate of 12.7%, and importantly, all living donors finally returned to their previous social lives. Precise functional and anatomical size matching between donor lobar graft and recipient could provide a favorable pulmonary function after LDLLT. We recently established multimodal surgical approaches, such as native upper lobe-sparing, right-to-left horizontally rotated, segmental, and single-lobe transplantation, in order to resolve the issue of size mismatch between the donor lobar graft and the recipient.