Over the past few years, advances have been made in the prevention, detection, and treatment of many of the most common cancers. Some of these advances have direct clinical application and are expected to save or lengthen the lives of thousands of patients with cancer each year. Important achievements have been made in the laboratory as well, where scientists have gained valuable insight into the molecular and genetic events that cause malignant transformation of normal cells. It is likely that the practice of oncology in the 1990s will incorporate much of this knowledge into the optimal treatment of patients with cancer.
Colon cancer strikes about 110 000 individuals per year in the United States.1 Of these, approximately 21000 have tumor that involves regional lymph nodes (ie, Dukes' stage C) at the time of diagnosis. Although all visible tumor may be removed by surgery, 50% to 60% of individuals with