The incidence of cancer increases progressively with age. Rearrangements of genomes have been found to accompany cellular aging. These factors, in concert with age-dependent alterations in immune function and host defense, may help to explain the increased risk of malignant disease in aged persons. The clinical presentation and natural history of neoplasia are also affected by aging. This conference reviews recent developments in these areas, examines the effects of drug use in the elderly and implications for management, and discusses current information on how age may influence the response of cancer to therapy.