Cancer of the breast. Epidemiology.

Though the etioolgy of mammary cancer in humans remains obscure, epidemiologic data, animal models and in-depth studies of patient populations are providing insights. The rapid progress and sophistication of these investigations promise to clarify with increasing precision the genetic and environmental determinants of risk, if not the fundamental cause. The importance of this information cannot be overestimated; inherent in it lies the possibility of prevention.