Cytogenetic conversion in a case of polycythaemia vera treated with interferon-alpha.

Polycythaemia vera is a clonal disorder of the haemopoietic stem cell causing a pathologic expansion of the erythroid and sometimes the megakaryocytic and myeloid elements. In order to avoid the possible mutagenic effects of radioactive phosphorus, alkylating agents and hydroxyurea, since 1988 alpha-IFN has been used for the treatment of PV and has been shown to induce and maintain haematological remission. We describe a 24-year-old PV patient with chromosomal abnormalities who achieved not only a reduction of the proliferation of erythroid elements and reticulin content in the bone marrow, but also a complete cytogenetic remission after IFN treatment.