What is the significance of micromegakaryocytes in peripheral blood?

micromegakaryocytes are typically seen in the peripheral blood in Myelodysplastic Syndromes (MDS) which are considered "pre-leukemia" syndromes because a high proportion of them progress to acute leukemia.

Micromegakaryocytes are caused by dysmegakaryocytopoiesis, meaning the bone marrow is not making normal megakaryocytes. Other megakaryocyte abnormalities may include large megakaryocytes that lack normal nuclear segmention, megs with two or more small unconnected nuclei, and "mononuclear" megs that lack normal nuclear lobation.