Unrelated bone marrow transplantation for beta-thalassemia patients: The experience of the Italian Bone Marrow Transplant Group

Bone marrow transplantation (BMT) remains the only potentially curative treatment for patients with thalassemia major. However, most candidates for BMT do not have a suitable family donor. In order to evaluate whether BMT from an HLA-matched unrelated volunteer donor can offer a probability of cure comparable to that obtained when the donor is a compatible sibling, we carried out a study involving 68 thalassemia patients transplanted in six Italian BMT Centers. Thirty-three males and 35 females (age range, 237 years; median age, 15) were transplanted from unrelated volunteer donors, all selected using high-resolution molecular typing of both HLA class I and II loci. Fourteen patients were classified in risk class I; 16 in risk class 2; and 38 in risk class III of the Pesaro classification system. Nine patients (13 %) had either primary or secondary graft failure. Fourteen patients (20 %) died from transplant-related causes. Grade II-IV acute graft-versus-host disease (GVHD) developed in 24 cases (40 %), and chronic GVHD in 10 cases (18 %). Overall survival (OS) in the cohort of 68 patients was 79.3 % (CI 67-88 %), whereas the Kaplan-Meier estimates of disease-free survival (DFS) with transfusion independence was 65.8 % (CI 54-77 %). In the group of 30 thalassemic patients in risk classes 1 and 2, the probability of OS and DFS were 96.7 %.