Alpha interferon: progress and perspectives in the biotherapy of chronic myelogenous leukemia

Chronic myelogenous leukemia is a myeloproliferative disorder representing 20%-30% of all leukemias. The disease is characterized by a cytogenetic abnormality called the Philadelphia chromosome. Except in patients who have undergone bone marrow transplantation (BMT), the natural history of chronic myelogenous leukemia has not changed in the last 30 years. Recombinant interferon alpha controls thrombocytosis and leukocytosis, reduces the leukemic infiltrate in the bone marrow, returns the spleen size to normal, and converts some patients to a normal chromosome pattern. This review summarizes the clinical and cytogenetic responses to date. The most significant observation is that, aside from treatment with BMT, interferon is the only agent that induces cytogenetic remissions.