Cytogenetic studies in twelve patients with primary myelofibrosis and myeloid metaplasia

Chromosome studies on bone marrow and/or peripheral blood cells without phytohemagglutinin were performed on 12 patients with primary myelofibrosis with myeloid meta-plasia (PMMM) between 1980 and 1984. Abnormal clones were found in six patients (50%). In five cases the abnormal clone involved the long arm of chromosome #7, two of which also had partial trisomy of chromosome #1 and trisomy of 9. Additional abnormalities involving chromosomes #3, #5, #11, #13, #15, and #21 were each found once. Review of the literature showed few studies on the cytogenetics of PMMM. No specific chromosomal pattern can be established; however, abnormalities described are nonrandom.