New directions in cancer control.

Cancer control is the reduction of cancer incidence, morbidity, or mortality through an orderly sequence from research on interventions to systematic application of the results to populations. To help ensure this progression, a system of classifying cancer control research into phases has been developed. These phases are hypothesis development, studies of methods, case-control studies, defined population studies, and demonstration-implementation. Studies of the potential impact of cancer control measures in defined populations are particularly needed. New research support should therefore be provided to research units focusing on this area of cancer control. A new community clinical oncology program will link community physicians with cancer center and university scientists in a cooperative cancer control effort. Another new cancer control program is called chemoprevention research, that is, clinical trials aimed at determining whether selected micronutrients or synthetic compounds can reduce the incidence of cancer.