Introduction and overview of interferon alfa in myeloproliferative and hemangiomatous diseases.

Both myeloproliferative and hemangiomatous diseases are characterized by abnormal cell proliferation. In myeloproliferative disorders, the abnormal growth involves hematopoietic progenitor cells of the marrow, whereas in hemangiomatous diseases, the abnormal growth involves endothelial cells of capillary blood vessels. Recombinant interferon alfa has shown promise in inducing remission in a number of myeloproliferative diseases, and, more recently, it has also been shown to be effective in treating several hemangiomatous disorders. In neither case is the mechanism of action of interferon alfa completely understood.