[Therapy of hairy cell leukemia with interferon]

Hairy cell leukemia is a rare lymphoproliferative disorder which is morphologically characterized by circulating lymphatic cells with prominent 'hairy' cytoplasmatic projections. Patients typically present with pancytopenia and splenomegaly. The bone marrow cannot be aspirated because of reticulin fibrosis. Chemotherapy was unable to influence the course of the disease satisfactorily. Therefore, splenectomy was the treatment of choice. The introduction of alpha-interferons into the therapy of hairy cell leukemia was a decisive breakthrough and is exemplary for the use of interferons in the treatment of malignant diseases. However, there are still many questions to be answered. The discussion of clinical implications is achieving growing importance in consequence of the availability of diverse commercial alpha-interferons for treatment of hairy cell leukemia.