Myelodysplastic syndrome with myelofibrosis: myelodysplastic syndrome as a major primary disorder for acute myelofibrosis.

Seven cases of myelodysplastic syndrome with myelofibrosis, which is defined using the following criteria: (1) pancytopenia with less than 5% blasts in the peripheral blood; (2) minimal or no splenomegaly; (3) myelofibrosis with cellular marrow; (4) absence of diffuse proliferation of blasts in the bone marrow; and (5) presence of myelodysplastic features of bone marrow or peripheral blood cells, are presented. They were in the range of 52-82 years old and consisted of 3 males and 4 females. Six out of 7 cases developed into acute leukaemia after 5 to 8 months from the onset and died from between 2 weeks to 8 months from the evolution to leukaemia. The type of leukaemia was acute myeloblastic in 3 patients, and acute myelo-megakaryoblastic in 3 patients. Another patient died of severe hepatic injury after 5 months from the onset of the disease. These findings revealed that the complication of myelofibrosis in the patients with myelodysplastic syndrome was an indicative sign of rapid progression to overt leukaemia or otherwise poor prognosis for survival. In addition myelodysplastic syndrome is thought to be major primary disorder for acute myelofibrosis. Myelodysplastic syndrome with myelofibrosis is closely associated with the neoplastic proliferation of megakaryoblasts in a considerable number of patients.