[Successful treatment with reduced-intensity stem cell transplantation for primary myelofibrosis].

: A 60-year-old man was found to have anemia and leukocytosis from a health examination, and diagnosed with primary myelofibrosis (PMF). He was treated with low-dose melphalan but required frequent transfusions of red blood cells, and his splenomegaly enlarged. He received reduced-intensity stem cell transplantation (RIST)from an HLA-identical unrelated donor. The recovery of hematopoiesis was delayed due to the small number of transplanted cells (0.4 x 10(8)/kg). Splenomegaly and myelofibrosis gradually improved, and transfusion was not necessary 6 months later. He died of pneumonia about 1 year after transplantation. However, this case suggests that RIST is an effective treatment for PMF with giant splenomegaly.