title: Aplastic anaemia and the hypocellular myelodysplastic syndrome: histomorphological, diagnostic, and prognostic features.
abstract: In a retrospective study of 111 patients with aplastic anaemia iliac crest biopsies were evaluated for the presence of morphological features statistically related to the evolution of the disease. Prognostic variables for a transition to acute non-lymphatic leukaemia were: cellular atypias of the three haemopoietic lineages, as observed in the myelodysplastic syndrome, and especially "micromegakaryocytes"; high numbers or irregular distribution of megakaryocytes, or both; and (slight) marrow fibrosis. Clinical variables did not influence these prognostic correlations. Prognosis in relation to death from bone marrow failure without leukaemia might well have been influenced by a strong plasma cell reaction, but this correlation was weakened by clinical factors. On the basis of this study aplastic anaemia can thus be subdivided morphologically into two disease entities--namely, hypocellular myelodysplastic syndrome with a 23-82% risk of acute non-lymphatic leukaemia developing within three years, depending on how many variables associated with acute non-lymphatic leukaemia are present, and non-dysplastic myelohypoplasia.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000741:Anemia, Aplastic / Q000473:pathology*; D001853:Bone Marrow / Q000473:pathology*; D002452:Cell Count; D002471:Cell Transformation, Neoplastic; D002648:Child; D006412:Hematopoietic Stem Cells / Q000473:pathology; D006801:Humans; D007938:Leukemia / Q000209:etiology*; D008533:Megakaryocytes / Q000473:pathology; D008875:Middle Aged; D011379:Prognosis; D012155:Reticulin; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D012155:Reticulin