An unusual hematopoietic stem cell transplantation for donor acute lymphoblastic leukemia: a case report

BACKGROUND: Donor acute lymphoblastic leukemia with recipient intact is a rare condition. We report a case of donor developing acute lymphoblastic leukemia 8 yrs after donating both bone marrow and peripheral blood hematopoietic stem cells. CASE PRESENTATION: This case report describes a 51-year old female diagnosed with acute lymphoblastic leukemia who donated both bone marrow and peripheral blood stem cells 8 yrs ago for her brother with severe aplastic anemia. Whole exome sequencing revealed leukemic genetic lesions (SF3B1 and BRAF mutation) only appeared in the donor sister, not the recipient, and an unusual type of hematopoietic stem cell transplantation with the recipient’s peripheral blood stem cells was done. The patient remained in remission for 3 months before disease relapsed. CD19 CAR-T therapy followed by HLA-identical unrelated hematopoietic stem cell transplantation was applied and the patient remains in remission for 7 months till now. CONCLUSIONS: This donor leukemia report supports the hypothesis that genetic lesions happen randomly in leukemogenesis. SF3B1 combined with BRAF mutation might contribute to the development of acute lymphoblastic leukemia.