Development of acute myeloid leukemia in patients with untreated chronic lymphocytic leukemia

The development of acute myeloid leukemia (AML) in patients with untreated chronic lymphocytic leukemia (CLL) is rare. We experienced a 65-year-old man who developed AML with aberrant CD7 expression and monoallelic CEBPA mutation during watchful waiting for CLL. He failed to achieve complete response (CR) by standard induction therapy for AML. We retrospectively reviewed 27 patients who developed AML with untreated CLL published between 1973 and 2016. The median age at diagnosis of AML was 68 years, and the median duration between the diagnoses of AML and CLL was 4.2 years. Diagnosis of AML and CLL was made simultaneously in 16 patients. The CR rate of AML was 42.9%, and the median survival was only 1.5 months after the diagnosis of AML. Patients who achieved CR tended to survive longer than those who did not. Our results demonstrated that the development of AML in patients with untreated CLL was associated with a poor response to chemotherapy and an extremely poor prognosis.