Cytogenetic heterogeneity of the acute leukemias.

Cytogenetic abnormalities have been found in approximately 50% of all patients with acute leukemia. Although no chromosomal abnormalities have been found which are characteristic of a specific cell type, patients with AML and DiGuglielmo's syndrome more frequently have hypodiploid chromosome numbers, while patients with ALL seldom have hypodiploid numbers of chromosomes and may actually exhibit an extreme degree of hyperdiploidy in the leukemic cells. Chromosome analysis may be helpful in characterizing patients with preleukemia and DiGuglielmo's syndrome, and aneuploidy may correlate with shortened survival in these conditions. Although data so far available are conflicting concerning the relationship of aneuploidy to response to therapy in patients with acute leukemia, it is possible that as improved therapeutic regimens become available for the treatment of acute leukemia, more sophisticated cytogenetic analysis may be helpful in predicting survival and response to therapy.