Leukemia in Patients with Klinefelter Syndrome: A Report of Two Cases.

Klinefelter syndrome (KS) is a chromosome abnormality characterized by a 47, XXY karyotype associated with hypogonadism and infertility. We present two cases of leukemia in patients with KS. The first patient presented with acute promyelocytic leukemia. He relapsed after the end of treatment. The second patient was diagnosed with chronic myeloid leukemia. Treatment with imatinib failed and the patient presented with myeloid blast crisis.