The preleukemic syndrome: clinical and laboratory features, natural course, and management.

The clinical and laboratory features of the stages in the evolution of acute nonlymphocytic leukemia are reviewed. Based on a retrospective analysis of 34 patients who died with an acute myelomonoblastic leukemia, the "preleukemic syndrome" has been shown to display a clinical picture sufficiently specific to permit its recognition prospectively (i.e., before the development of overt leukemia). The results to date of a variety of prospective studies are reviewed, and the approach(es) to the management of these cases is considered.