Abstract
The importance of prevention in reducing the morbidity and mortality from cancer has been widely recognized. With the demonstration of tamoxifen's ability to prevent breast cancer in women, the feasibility of cancer chemoprevention in humans is now established. Future clinical chemoprevention studies should focus on phytochemicals, cancer preventive compounds in fruits, vegetables and other plants. Many phytochemicals are excellent potential chemopreventive agents, because, in addition to their cancer preventive effects, they are relatively non-toxic and inexpensive, they can be taken orally and some of them have other health benefits as well. New opportunities in clinical chemoprevention research include investigating chemopreventive effects of phytochemicals and conducting studies in patients with cancer. There is also a great need to investigate potential benefits and risks of administering phytochemicals before, during or after conventional therapies, such as surgery, chemotherapy, radiation or hormonal therapy. In addition, administration of chemopreventive agents prior to surgery provides an opportunity to investigate the modulation of genetic and epigenetic pathways by putative cancer preventive compounds and nutrients.