IMMUNE-MEDIATED AND UNUSUAL COMPLICATIONS DURING INTERFERON-ALFA THERAPY IN CHRONIC MYELOGENOUS LEUKEMIA

Purpose: Long-term treatment with interferon alfa (IFN alpha) can prod uce or exacerbate immune-mediated complications (IMC), The purpose of this study wets to analyze the experience with IMC and unusual complic ations in patients with chronic myelogenous leukemia (CML) undergoing IFN alpha treatment. Patients and Methods: The occurrence of IMC and u nusual complications was evaluated in patients with Philadelphia chrom osome (Ph)-positive CML. Results: Well-documented and clinically evide nt complications developed in 35 patients after a median of 14 months of IFN alpha treatment. These included 28 (5%) of 581 patients with Ph -positive CML treated with IFN alpha-containing regimens at M.D. Ander son Cancer Center (MDACC) and seven patients referred for opinion or p roblems who were on other studies. Hypothyroidism occurred in 11 patie nts (2%), immune-mediated hemolysis in seven (1%), and connective tiss ue diseases in 11 (2%). Other unusual occurrences included congestive heart failure (CHF; n = 4), porphyria cutanea tarda (PCT; n = 3), memb ranous glomerulonephritis (MGN; n = 1), and vitiligo (n = 1), IFN trea tment was discontinued in 19 patients and the dose was reduced in five , Ten of 11 patients (91%) with immune-mediated hypothyroidism and eig ht of 11 (73%) with connective tissue diseases had some degree of cyto genetic response at the time of the event. Conclusion: Although the fr equency of IMC is low, patients treated with IFN alpha should be monit ored for signs and symptoms of autoimmunity. (C) 1995 by American Soci ety of Clinical Oncology.