Chronic neutrophilic leukemia: description of a new case with karyotypic abnormalities

A further case of chronic neutrophilic leukemia (CNL) is reported. On karyotype analysis of the bone marrow aspirate, all of the examined cells showed trisomy of chromosome 9 and partial deletion of the long arms of chromosome 20. This anomaly has never before been reported in CNL, and it could be directly associated to the disease.