Several prospective randomized studies have shown that the treatment of chronic myeloid leukemia with interferon alfa (IFNa) prolongs the survival by comparison with conventional chemotherapy. However, long-term treatment with Interferon alfa (IFNa) can produce or egacerbate Immune-mediated complications (IMC). The purpose of this study was to analyze the egperience with IMC in patients with chronic myelogenous leukemia (CML) undergoing IFNa treatment. Patients and methods: The occurence of IMC was evaluated in 76 patients (47 male; 29 female) with Philadelpia chromosome (Ph)-positive CML. The median of age was 45 years and the duration of disease was 3,9 years. Diagnostic criteria of IMC esere performed in patients with sign and symptoms suggestive of particular disorders. Results: Well-documented and clinically evident complications developed in 7 patients after a median of 19 months (range 1-84) of IFNa treatment. These included 9,2 % patients with Ph-positive CML treated with IFNa-containing regimens. Hypothyroidism (H) occured in 1 patient (1,3 %), Immune-mediated hemolysis (HEM) in 2 patients (2,6 %) and connective tissue disorders (CTD) in 4 patients (5,3 %) [2-SLE, 1-Raynad's syndroma and 1-miged connective tissue syndrome (MCTS)]. IFNa was discontinued in 3 patients and the dole was reduced in 2 patients. Five of 7 patients (75 %) with Immune-mediated complications had some degree of cytogenetic response at the time of the event. The association with female seg was strong and significant (86 % vis 33,6 %, g2; 48; p = 0,02). Conclusion: The frequency of IMC of clinical relevance with interferon alfa therapy in CML increased (long-term therapy). The patients treated with interferon alfa should be monitored for sign and symptoms of autoimmunity.

        Key words: Chronic myeloid leukemia - Interferon alfa therapy - Immune-mediated complications