Down's syndrome and acute megakaryoblastic leukaemia. Case report and review of the literature.

A case is reported of a child with Down's syndrome who developed acute megakaryoblastic leukaemia, and in whom the evolution of the disease was accompanied by increasing cytogenetic abnormalities. A review of the literature suggests that the presence of an abnormal chromosome 21 may predispose to the development of this type of leukaemia.