Cytogenetics of bone marrow fibroblastic cells in idiopathic chronic myelofibrosis.

To determine the nature of the fibroblastic proliferation in myelofibrosis, we studied the cytogenetic composition of a pure population of in-vitro bone marrow fibroblastic cells (FC) from a patient with idiopathic chronic myelofibrosis who had trisomy 8 in her unstimulated peripheral blood cells. This cytogenetic abnormality was absent in all the FC studied supporting the premise that in the myeloproliferative disorders the myelofibrosis represents a secondary or non-neoplastic reaction to the clonal proliferation of haematopoietic stem cells.