[Polycythemia vera terminating in myelodysplastic syndrome].

A 77-year-old male, who had been treated with carboquone and busulfan for polycythemia vera (PV), developed myelodysplastic syndrome (MDS) 8 years later. On admission the peripheral blood revealed pancytopenia, but blastoid cells were not noted. The bone marrow showed hypercellularity, and functional and morphological abnormalities in trilineages of hemocytes. Cytogenetic study showed complex abnormalities involving chromosomes 5 and 7. We diagnosed this case as secondary MDS to alkylating agents. He was treated with 1, 25 (OH)2 vitamin D3. However, it was not effective and the percentage of myeloblasts increased to 14.4%. In spite of supportive therapy, he died of sepsis due to urinary tract infection.