The molecular basis of colon cancer.

There are approximately 160,000 new cases of colon cancer every year in the United States. Colon carcinoma results from the aggregate effects of multiple genetic alterations. Some genetic alterations may be inherited, while others reflect somatic mutations. The latter may themselves be the indirect result of environmental factors such as diet. It is the total accumulation of these genetic changes, combining the activation of oncogenes with the inactivation of tumor suppressor genes, that is responsible for determining the biologic properties of colon cancer.