HYPERFIBROTIC MYELODYSPLASIA - A POSSIBLE NEW ENTITY (REVIEW)

Fibrosis of the bone marrow may be present in various hematologic dise ases such as myeloproliferative diseases (MPD) and acute myeloid leuke mias (AML). In primary myelodysplastic syndromes (MDS) myelofibrosis i s a relatively rare event. Patients affected by MDS with myelofibrosis (H-MDS) present intriguing features that give rise to the hypothesis that H-MDS might represent a new entity. The purpose of this concise r eview is to summarize the contrasting opinions of the authors who have described some series of H-MDS patients. Many characteristics induce one to distinguish H-MDS from classical MDS, so that the former has be en considered each time as a transitional stage between MDS and MPD, a n acute transformation of an MPD, or an AML from the beginning. The pa thogenetic mechanism of the fibrosis of the bone marrow may be similar to sic sic of the MPD in which a stimulus to secrete reticuline or co llagen derives from abnormal marrow megakaryocytes. Importance of kary otype abnormalities are discussed. Clinical features of the syndrome a re rather heterogeneous; evaluation of the survival of the described s ingle cases reveals that mean survival is not significantly different from classical MDS. Finally, trephine biopsy and the cytogenetic study are necessary to permit the diagnosis of H-MDS. However, because of t he relatively low number of cases, series of patients are necessary to correctly classify this syndrome.