Evaluation of dysplasia through detailed cytomorphology in 3156 patients from the Düsseldorf Registry on myelodysplastic syndromes.

Using the Düsseldorf MDS registry with standardized cytomorphology we here describe dysplastic features in detail, concentrating on 16 different dysplastic features in the blood and 19 in the marrow in 3156 patients. The most frequent dysplastic features were megaloblastoid changes and bi- and multinuclearity in the erythropoiesis, pseudo-Pelger cells and hypogranulation in the granulopoiesis and micromegakaryoctes and mononuclear megakaryocytes in the megakaryopoiesis. The frequency of dysplastic changes did not differ significantly among the WHO types with the exception of MDS with del(5q) and CMML types. No single sign of dysplasia is exclusive for the diagnosis of MDS.