title: Myelofibrosis in chronic myeloproliferative disorders. Incidence among subtypes according to the Hannover Classification.
abstract: The distribution and the development of fibrosis were evaluated from bone marrow biopsies of patients with chronic myeloproliferative disorders (CMPD), regarding two groups of patients: (1) 564 with follow-up biopsies over a period of up to twelve years observation time, and (2) 1.787 diagnostic bone marrow biopsies from CMPD patients. Fibrosis was divided into three grades of fiber increase: early myelosclerosis, myelofibrosis, and advanced myelofibrosis. The first group of sequential BMB showed a significant progress to myelofibrosis in so-called "Chronic Megakaryocytic-Granulocytic Myelosis"--CMGM-, which corresponds to Agnogenic Myeloid Metaplasia-AMM-in 72.4% (21/29 patients), as well as in CML with megakaryocytic increase-CML.MI-in 39.2% (20/51). In the second group of diagnostic biopsies, only 30% of CMGM cases showed no fibrosis. In P. vera, 16.2% (18/111) developed myelofibrosis up to twelve years later. This figure was 4.3% (2/46) in Primary Thrombocythemia. Increase of megakaryocytes in CML indicates a high risk for developing fibrosis, combined with reduced life expectancy.
authors.affiliation: Pathologisches Institut, Medizinische Hochschule Hannover, FRG.
authors.forename: T
authors.initials: T
authors.lastname: Buhr
authors.forename: A
authors.initials: A
authors.lastname: Georgii
authors.forename: H
authors.initials: H
authors.lastname: Choritz
mesh_terms: D001706:Biopsy; D001853:Bone Marrow / Q000473:pathology; D002908:Chronic Disease; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D009196:Myeloproliferative Disorders / Q000145:classification / Q000473:pathology*; D055728:Primary Myelofibrosis / Q000453:epidemiology* / Q000473:pathology; D012042:Registries; D012189:Retrospective Studies