Chemoprevention of colon cancer

Animal tumor experiments and epidemiologic studies suggest that several agents may be of potential value in blocking the development of colon adenomas and carcinoma. Recent laboratory investigations have demonstrated several intermediate markers that are altered in the colonic epithelium of high-risk individuals and that can be modulated by several possible chemopreventive agents. Calcium and ascorbic acid are two agents that have been investigated in preliminary studies. Although the results have not been striking, these studies have pointed up methodologic issues that must be addressed and will contribute greatly to the design of the next generation of trials. Given the advances in the elucidation of the carcinogenic processes in colon cancer, it is reasonable to hope that the next decade of research will discover chemoprevention strategies that will protect individuals from the development of the most common tumor in Western society.