Matched sibling donor hematopoietic stem cell transplantation for thalassemia

Bone marrow transplantation is the only curative treatment for severe thalassemia. Since its successful first report in 1981, more than 4000 patients with this disease worldwide underwent bone marrow transplantation. The purpose of this review is to update the most recent reports of matched sibling donor hematopoietic stem cell transplantation in thalassemia.

Advanced and improved transplant techniques result in the improved outcomes in those transplants from a matched sibling donor with transplant-related mortality less than 5%. Class 3 patients aged at least 7 years and liver enlargement at least 5 cm have a very high risk of graft rejection and regimen-related toxicity. This subset of patients require innovative approaches to overcome the morbidity and mortality. Those include the addition of hydroxyurea, azathioprine, and fludarabine as preconditioning to busulfan, thiotepa, and cyclophosphamide. Novel conditioning consisting of pretransplant immunosuppression with two cycles of fludarabine and dexamethasone followed by reduced intensity conditioning with fludarabine, busulfan, and thymoglobulin has been developed.

Bone marrow transplantation in young low-risk (class 1 and 2) patients should be performed as soon as possible. For class 3 severe thalassemia, novel conditioning regimens have been developed to overcome graft rejection and regimen-related toxicity. Hematopoietic stem cell transplantation in adults who have been well chelated should be offered with clinical trials.