Chronic myelogenous leukemia occurring in a chronic lymphocytic leukemia patient

: Occurrence of two different hematological malignancies is very infrequent, and it is nevertheless important not to neglect basic examinations in patients follow-up. A 65-year-old patient was referred to our institution for his chronic lymphocytic leukemia (CLL) checkup; we report the different steps leading to the diagnosis of a second hematological malignancy.