Occurrence of a Ki-1-positive anaplastic large-cell lymphoma in a patient with Ph′ positive chronic myelogenous leukemia successfully treated by alpha-interferon

We describe a patient with Philadelphia-chromosome-positive (Ph′ +) chronic myelogenous leukemia (CML), who developed an anaplastic large cell lymphoma (ALCL) with T-phenotype, after 43 months successful treatment with alpha-interferon (IFN). Characterization studies of lymphoma cells showed positivity for Ki-1 monoclonal antibody, T-cell surface markers, T-cell receptor beta chain rearrangement, and germline configuration of the BCR gene. At the time of lymphoma diagnosis, the patient had achieved complete hematologic remission from CML with partial karyotypic conversion (50% Ph′ + cells). After twelve weekly courses of polychemotherapy, he obtained complete remission from lymphoma. At present, five years from CML diagnosis, the patient has a remarkably stable disease, being in remission from lymphoma and in well controlled CML chronic phase. Our case thus represents the first well documented description of a T-cell non-Hodgkin's lymphoma developed during the course of CML.