Trisomy 13 in bone marrow cells in acute myelocytic leukemia and myelofibrosis

We have identified trisomy 13 in two additional patients with hematologic malignancies involving the hematopoietic stem cell: a 75-year-old female with acute myelocytic leukemia and a 64-year-old female with agnogenic myelofibrosis and myeloid metaplasia. Chromosome analysis of the direct bone-marrow preparation showed 100% of cells with trisomy 13 in the first and 10% of cells in the second. We also previously reported a patient with Ph1 negative chronic myelogenous leukemia in whom 100% of the marrow cells showed an identical trisomy. The probability of finding three such patients in our case material was calculated to be 0.05--0.08, implying that trisomy 13 may be another nonrandom chromosomal aberration associated with malignancies of hematopoietic pluri-potent stem cell.