Association of allograft rejection with reduction of immunosuppression for post-transplant lymphoproliferative disorder: Analysis of a 20-year single-institutional experience.

Abstract

e19047 Background: Post transplant lymphoproliferative disorder (PTLD) is a rare, but potentially fatal complication of transplantation and therapeutic immunosuppression (IS). The cornerstone of PTLD management is reduction of IS, which carries the risk of allograft rejection. Methods: Retrospective analysis of patients diagnosed with PTLD after solid organ (SOT) or allogeneic stem cell transplant (HSCT) at the University of Florida were identified through a review of individual EMR charts. This analysis focused on rates of allograft rejection and graft failure with RI. Results: Of 138 patients diagnosed with PTLD between 1994 and 2016, 15% (n = 20) experienced allograft rejection during PTLD treatment. The primary organ of transplant and rejection included liver (35%), lung (25%), heart (10%), HSCT (15%) and kidney (15%). Median age at PTLD diagnosis was 14.5 years (range 2-59), males (50%) and median time from transplant to PTLD diagnosis was 25 months (range 0-173). RI was a documented as a component of initial PTLD treatment in 19/20 (95%) patients, with 2/20 (10%) undergoing complete withdrawal of immunosuppression, 13/20 (65%) partial RI (withdraw of one or more drugs) and 3/20 (10%) dose reductions of their established IS regimen. One lung recipient (5%) was transitioned to an alternative agent, and one patient had no documented records of IS adjustment. Treatment for acute rejection included observation 2/20 (10%), pulse steroids 11/29 (55%) or IS increase 12/20 (60%). 7/20 (35%) received combination steroids and increased IS. Allograft failure developed in 5/20 (25%) (1 kidney, 1 lung, 1 heart, 1 liver, 1 BMT). Allograft failure was not shown to correlate with RPI score at diagnosis, organ transplanted, induction therapy at transplant or 3-year OS. Of note 5/5 (100%) of patients received Rituximab as part of initial treatment, versus 5/15 patients whose grafts survived. Conclusions: RI for PTLD is associated with moderate rates of response, however acute graft rejection is common and is associated with high rates of graft failure. PTLD may still have favorable outcomes when combining partial RI with chemotherapy and Rituximab.