Successful treatment of refractory T-cell acute lymphoblastic leukemia by unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling

Summary: We describe a patient with refractory T-cell acute lymphoblastic leukemia who successfully underwent unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling. In order to avoid severe graft-versus-host disease (GVHD), we used intensified GVHD prophylaxis consisting of tacrolimus, a short course of methotrexate, methylprednisolone, and mycophenolate mofetil. Hematopoietic reconstitution was rapid, with neutrophil count >5 × 10 8 /l on day +16, and platelet count >2 × 10 10 /l on day +25. There was no evidence of clinical acute GVHD. Bacterial, fungal, and viral infections were well controlled with antibiotics. The patient is still in complete remission past day +400. We suggest that unmanipulated HLA-mismatched transplantation with intensified GVHD prophylaxis is an alternative option for patients who do not have an HLA-identical donor.