Myelodysplastic syndrome with increased marrow fibrosis: a distinct clinico-pathological entity.

Seventeen cases of myelodysplastic syndrome (10 primary and seven secondary to previous radio-chemotherapy), characterized by trilineage dysplasia, severe bone marrow fibrosis and a high number of megakaryocytes, are described. All of these patients had similar clinical and prognostic features consisting of pancytopenia, modest or absent visceral enlargement and poor survival. The use of CD61 antibodies, which recognize megakaryocytic cells at all stages of maturation, confirmed that these patients had a higher number of these cells than either normal subjects or patients affected by myelodysplastic syndrome (MDS) without fibrosis. Furthermore, primary and secondary MDS with fibrosis, although clinically and histopathologically similar, differed in terms of the number of megakaryoblasts which were significantly higher in primary forms (P less than 0.02). We conclude that MDS with fibrosis may represent a clinicopathological entity which needs to be distinguished from other MDS subtypes as well as from idiopathic myelofibrosis or malignant myelosclerosis.