[Allogeneic hematopoietic stem cell transplantation with high-dose melphalan and total body irradiation for hematological malignancies: a single-center retrospective analysis].

We retrospectively analyzed outcomes for 12 patients with hematopoietic malignancies who underwent allogeneic stem cell transplantation between January 2005 and December 2023 using a myeloablative conditioning regimen with melphalan (180 mg/m2) and total body irradiation (8-12 Gy). Median age at transplantation was 41.5 years (range, 17-51 years) and underlying diagnoses were acute myeloid leukemia (n=5), acute lymphoblastic leukemia (n=5), myelodysplastic syndrome (n=1), and adult T-cell leukemia/lymphoma (n=1). Median follow-up was 32 months (range, 1-190 months). Neutrophil engraftment was achieved in 11 patients. Three-year overall survival, progression-free survival, and relapse rates were 47.6%, 41.7%, and 33.3%, respectively. Grade3 mucositis was observed as a conditioning regimen-related toxicity in 10 patients. The most common causes of death were infection (n=3) and disease progression (n=3). The 2-year non-relapse mortality rate was 25.0%, suggesting that this conditioning regimen would have limited indications.