Myeloid dysplasia: the histopathology of preleukemia.

The clinical term “preleukemia” is understood as an alteration of the bone marrow and peripheral blood preceding overt acute myeloid leukemia (AML, review by Saarni and Linman 1973). However, in the majority of cases the diagnosis is only a retrospective one, derived from many mostly clinical and cytogenetic investigations (Fisher et al 1973: Dreyfus 1976; Linman and Bagby 1978; Pierre 1978). The aim of our study was to determine whether there are characteristic lesions of the bone marrow preceding obvious leukemia and if wether those lesions are similar in cases evolving AML or CML later on.