Tetraploidy/near-tetraploidy acute myeloid leukemia.

A tetraploid/near tetraploid (T/NT) karyotype is a rare finding in acute myeloid leukemia (AML). Here we report 38 AML patients with a T/NT karyotype, including 26 men and 12 women with a median age of 65 years. T/NT karyotype was detected at initial diagnosis of AML in 16 patients, and acquired during the course of disease in 22 patients. All patients showed large blasts with frequent prominent nucleoli, cytoplasmic vacuoles and/or inclusions, nuclear irregularity and/or budding. Eleven patients had a non-complex and 27 had a complex T/NT karyotype; 21 patients also had pseudodiploid and/or triploid clones. After T/NT karyotype detection, 32 patients received chemotherapy and 10 also received stem cell transplant. After a median of 6.2 months follow-up, 32 patients died of disease or complications, 5 were alive with complete remission, and 1 alive with persistent AML. Median overall survival (OS) was 5 months. Patients with a non-complex T/NT karyotype had a significantly superior OS compared to those with a complex T/NT karyotype (10.7 vs. 3.4 months, p=0.0280). We conclude that T/NT karyotype in AML is often associated with distinctive morphologic features and conveys generally poor outcomes. Distinction of complex versus non-complex T/NT karyotype provides further prognostic information.