Same Sibling Marrow Following Cord Allogeneic Transplantation As Therapy for Second Relapse APL: A Pediatric Case Report

The optimal treatment for relapsed acute promyelocytic leukemia (APL) in pediatric patients is controversial. Allogeneic hematopoietic stem cell transplantation is an alternative for consolidation therapy for these patients, with published event-free survival rates of 70-75%. We report a pediatric patient with acute promyelocytic leukemia (APL) who relapsed 28 months after cord blood transplantation from her sibling and then successfully treated with bone marrow transplantation from the same donor after reinduction.   First relapse occurred at 2 years of age, 4 months after induction therapy with ATRA, cytarabine and daunorubicin, during consolidation with ATRA and adriamycin. Sibling donor matched cord blood transplantation was performed after successful reinduction with arsenic trioxide, using myeloablative conditioning regimen with busulfan and cyclophosphamide and cyclosporine for GVHD prophylaxis. Second relapse was also treated with arsenic trioxide, and matched sibling bone marrow transplant from the same donor 32 months after the cord blood transplant, using conditioning with TBI, cytarabine and cyclophosphamide and low level cyclosporine prophylaxis. Chronic skin GVHD with moderate scleroderma has developed, currently under control, and this patient is now with no evidence of malignancy and persistent molecular remission at 40 months post-second transplantation, approximately 6 years and 8 months from diagnosis. This case report demonstrates the role of graft-versus-leukemia activity in APL and vividly illustrates the role of different cell sources from same donor in allogeneic transplantation for pediatric patients.