Lymphoma in primary chronic cold hemagglutinin disease treated with chlorambucil

Two patients with primary chronic cold hemagglutinin disease (CHAD) were treated with chlorambucil for ten and 7 1/2 years, with cumulative doses of 14 and 6.6 g, respectively. Both responded favorably, and malignant lymphoma eventually developed in both of them. An attempt to assess the incidence of lymphoma as part of the natural course of untreated CHAD failed for want of proof. Literature since 1970 reported no chlorambucil-associated lymphoma. Of 77 responses to a questionnaire mailed to 135 US hematology-oncology programs, 76 reported no examples of chlorambucil-associated lymphoma. One response, however, did relate that diffuse histiocytic lymphoma developed in three of 141 patients receiving prolonged chlorambucil therapy for polycythemia vera. Alkylating-agent therapy for CHAD might be associated with development of lymphoma.