title: Relation between leukaemic cell count and degree of maturation in acute myeloid leukaemia.
abstract: In acute myeloid leukaemia the peripheral leukocyte count is known to be a prognostic factor. The preserved capacity of leukaemic cells to mature has also been suggested to be one. In a series of 179 cases of adult acute myeloid leukaemia peripheral leukaemic cell count and degree of maturation were found to be inversely correlated. As the degree of maturation of leukaemic cells in peripheral blood was lower than that in bone marrow in the majority of cases, blast cells appear to be released more easily from the marrow than cells that have matured to some extent in the direction of the larger promyelocytic or promonocytic cell type. In a series of 35 cases we found peripheral blast cells to be smaller than those in bone marrow. Moreover, central blast cell diameter and peripheral leukaemic cell count were inversely correlated. Therefore, leukaemic cell size or some factor related to it may contribute to the preferential egress of small immature cells from the marrow. Differences in proliferative activity could not account for the inverse correlation between degree of maturation and leukaemic cell count.
mesh_terms: D000328:Adult; D001853:Bone Marrow / Q000473:pathology; D006098:Granulocytes; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000097:blood / Q000473:pathology*; D007958:Leukocyte Count; D007962:Leukocytes / Q000473:pathology*; D008938:Mitosis; D011379:Prognosis