Thiotepa/cyclophosphamide/TBI as a conditioning regimen for allogeneic hematopoietic stem cell transplantation in patients with myelodysplastic syndrome

In all, 18 patients (30 - 56 years; median 49) with MDS underwent allogeneic HSCT from related ( n = 12) or unrelated ( n = 6) donors after a conditioning regimen comprising thiotepa, cyclophosphamide, and TBI. GVHD prophylaxis consisted of cyclosporine ( n = 15) or tacrolimus ( n = 3) with short-course methotrexate. Four patients had low-risk disease ( refractory anemia or complete remission after chemotherapy) and 14 patients had high-risk disease (RAEB, RAEB-t, or AML). Grade II - IV acute GVHD developed in six patients and chronic GVHD in 10. With a median follow-up of 31 months, the 2-year survival probability is 75% for low-risk patients and 57% for high-risk patients. One patient died of leukemia and six of treatment-related causes. This conditioning regimen requires further study in patients with MDS.