Epidemiology of leukemia and lymphoma.

The causes of acute leukemia and lymphomas are still largely unknown. These malignancies account for approximately 6% of cases of cancer in the US population, and active research efforts are now underway to define etiologically important genetic or environmental factors for these conditions. Recent epidemiologic studies have focused on international variations, secular trends, genetic syndromes, familial aggregation, chromosomal abnormalities, environmental exposures, and unique subgroups defined either demographically or biologically.