Risk factors evaluation of post-transplant lymphoproliferative disorders after allogeneic haematopoietic stem cell transplantation with comparison between paediatric and adult.

To describe the clincopathological features and evaluate risk factors of post-transplant lymphoproliferative disorder (PTLD) after allogeneic haematopoietic stem cell transplants (allo-HSCT), with comparison between paediatric and adult .Clinicopathological features of 81 cases of PTLD after allo-HSCT were analysed by histopatholgy, immunohistochemistry and in situ hybridisatioin.The cases included 58 males and 23 females with a median age of 26.7 years (range 6-55 years) and the PTLDs developed 1-60 months post-transplant (mean 5.9 months). The histological types indicated 10 cases of non-destructive PTLD, including 4 of plasmacytic hyperplasia, 5 of infectious mononucleosis and 1 of florid follicular hyperplasia. Fifty-six cases were polymorphic PTLD, and 15 were monomorphic PTLD, including thirteen of diffuse large B cell lymphoma, 1 of extranodal nasal type natural killer (NK)/T cell lymphoma and 1 of plasmablastic lymphoma. Foci and sheets of necrosis were observed in 31 cases. The infected ratio of Epstein-Barr virus (EBV) was 91.4%. Some cases were treated by reduction of immunosuppression, antiviral therapy, donor lymphocyte infusion or anti-CD20 monoclonal rituximab. Thirty-three cases died. Compared with that of adult, overall survival of paediatric recipient may be better.The first half year after allo-HSCT is very important for the development of PTLD. Type of PTLD, EBV infection and graft-versus-host disease are risk factors. The prognosis of PTLD is poor, and PTLD after allo-HSCT exhibits some features different from that after solid organ transplantation and some differences existing between adult and paediatric recipients.