[Low dosage long-term treatment with recombinant alpha interferon induces in hairy cell leukemia continuous complete remission].

Long-term treatment with recombinant interferon alpha (IFN) leading to complete remission in a patient with hairy cell leukaemia is presented. Four months after the beginning of treatment with IFN, the parameters of the peripheral blood had normalized. In spite of a continuous dose reduction (to a dose of 1 Mio. U/week) remission could be maintained during the six years of treatment. Two years after the start of treatment with IFN, a metastasizing carcinoma of the prostate was diagnosed, leading to death after four years. With regard to the hairy cell leukaemia, the patient was free of symptoms and the obduction confirmed the complete remission: the histological examination of bone marrow, spleen, liver and lymph nodes showed no more signs of hairy cell leukaemia. This case report shows that long-term treatment with IFN in some cases is effective to induce and to maintain complete remission in hairy cell leukaemia.