Maturation and proliferation capacity of blood cells from untreated acute myeloid leukemia and its prognostic significance.

Blood cells from 68 patients with untreated acute myeloid luekemia were cultured in RPMI-medium without stimulating factors up to ten days. The cultures showed in part maturation and proliferation to monocytes-macrophages, in part to promyelocytes, myelocytes and Pelger-like cells, in part we did not find any differentiation or the cultures were degenerated during the first days. Retrospectively we found that in the 16 blood cell cultures with capacity to differentiation into the monocyte-macrophages-system 5 patients had a smouldering leukemia. Our preliminary evidences suggest that the diagnosis "smouldering leukemia" is to be found with out in vitro culture system. Further analysis suggest that patients with acute leukemia whose blood cells have the capacity for maturation to monocytes-macrophages or to promyelocytes, myelocytes and Pelger-like cells have a better chance of achieving a complete remission and a longer median survival time.