Bone marrow histological modifications induced by alpha interferon in hairy cell leukemia.

This paper reports the bone marrow histological picture in 7 patients with hairy cell leukemia treated with recombinant interferon. Bone marrow biopsies were performed at diagnosis, after 1, 3 and 7 months from the beginning of treatment and at 12 months at treatment suspension. The main modifications observed were a conspicuous reduction of hairy cell infiltrate, profound hypoplasia induced by the drug, early evidence of focal erythropoiesis followed by the appearance of other hematopoietic series and a progressive reduction of the reticulum. The clinical response to interferon therapy was good in all the patients studied; however future studies will have to evaluate the duration of response after treatment suspension.