A CASE OF DIFFUSE LARGE B-CELL LYMPHOMA TRANSFORMED FROM FOLLICULAR LYMPHOMA WITH SUCCESSFUL GRAFT-VERSUS-LYMPHOMA EFFECT ON EARLY RELAPSE AFTER CORD BLOOD TRANSPLANTATION

Abstract

A 71-year-old man developed hydronephrosis due to retroperitoneal lymph node swelling. He was diagnosed with follicular lymphoma (FL). However, FL transformed into a diffuse large B-cell lymphoma (DLBCL) during chemotherapy. He became refractory to chemotherapy and a large mass was formed in the right anterior chest. Therefore, he was referred to our hospital for an allogeneic hematopoietic cell transplantation (Allo-HSCT). After complete response/unconfirmed with radiation therapy for tumor, he received cord blood stem cell transplantation (CBT) following a reduced intensity conditioning regimen with fludarabin, melphalan, and total body irradiation and tacrolimus with mycophenolate mofetil for graft-versus-host disease (GVHD) prophylaxis. On day 16 after CBT, his neutrophil count engrafted. However, his lactate dehydrogenase levels (LDH) elevated, and on day 23, bone marrow biopsy showed mixed donor chimerism and fluorescence in situ hybridization demonstrated both MYC and BCR gene fusion. We discontinued immunosuppressants on day 26. His LDH level decreased, and bone marrow biopsy showed full donor chimerism on day 55 with no evidence of GVHD. We think the graft-versus-lymphoma (GVL) effect was induced only by discontinuation of the immunosuppressants. The methods of induction of GVL to treat early relapse of lymphoma after Allo-HSCT need to be developed in a future study.