Chemoprevention: Progress And Opportunity

Abstract

A generally accepted definition of chemoprevention is the administration of purified chemical agents for the prevention of clinical cancer. This concept is commonly thought to have emerged a little over two decades ago and is attributed to cancer biologists who were elucidating the role of various natural substances and pharmacologic agents on the stepwise progression of cancer.26 However, a brief review of public health and medical advances over the twentieth century will reveal that the concept and application of chemoprevention for various disease processes evolved directly from the great successes of nutritional scientists in the early decades of this century. Regardless of the conceptual origins of cancer chemoprevention, the progress in identifying agents, testing them in preclinical models, followed by human intervention studies, has rapidly accelerated in recent years. The century ends with the success of the Breast Cancer Prevention Trial (BCPT) illustrating the ability of the anti-estrogen Tamoxifen to prevent breast cancer in a cohort of women at high-risk.10 Indeed, it is our opinion that chemoprevention, tobacco control, and the application of early detection strategies provide the opportunity to reduce cancer mortality by at least 50% within a generation.11 The objective of this review is to provide the broad audience of cancer prevention investigators with a brief overview of the progress and future promise of cancer chemoprevention.