Adjuvant therapy of colon cancer.

Colon cancer is an important cause of cancer-related mortality. A series of clinical trials of adjuvant systemic therapy have been performed in attempt to establish means to improve outcome in this disease. By the early 1990s, a role for 5-fluorouracil (5-FU)-based chemotherapy in stage III colon cancer had been firmly established. The precise role for chemotherapy in stage II disease remains under investigation. Progress continues toward optimizing the schedule and duration of systemic therapy, allowing for maximal efficacy with a minimum of toxicity. It appears that approximately 6 months of 5-FU and leucovorin are as effective as more prolonged regimens. Levamisole does not appear to add to the benefit of 5-FU and leucovorin. Several newer agents such as the oral fluorinated pyrimidines, irinotecan (CPT-11) and oxaliplatin have demonstrated activity in metastatic colon cancer and hold promise as potentially effective drugs to be tested in the adjuvant setting.