Myelodysplasia and myeloproliferative disorders.

Myelodysplasia and the myeloproliferative disorders are clonal hematopoietic stem cell disorders with heterogeneous clinical presentations and prognoses. This review highlights some of the recent progress that has been made in these disorders. Specifically, a number of studies have enhanced our understanding of the pathogenesis of these disorders, and potentially useful animal models for primary myelofibrosis have been developed. New, clinically useful prognostic scoring systems have been devised for myelodysplasia and for primary myelofibrosis. New chemotherapeutic approaches and nonmyelosuppressive alternative therapies for myelodysplasia have been studied. Data on the use of interferon for polycythemia vera and the potential leukemogenesis of hydroxyurea have recently become available. Finally, continued progress has been made in the use of allogeneic (related and unrelated donor) and autologous stem cell transplantation for myelodysplasia.