Adjuvant therapy in colon cancer: current status and future directions.

The role of adjuvant chemotherapy in patients with stage III colon cancer is now well established and 5-FU/LV should be the reference regimen to which new drugs are tested against in the adjuvant setting. In stage II colon cancer, because the risk of recurrence is lower, any absolute benefit of chemotherapy is likely to be less than in stage III disease. The studies performed so far have been generally underpowered to detect what might be a clinically significant effect on survival. Molecular profiling of tumours may identify individuals more likely to benefit from adjuvant therapy and tailor individual treatment in the future. After potential curative treatment for localised colon cancer, about two out of five patients will experience disease recurrence, but the most effective strategies for follow-up remain to be established. New drugs such as irinotecan, oxaliplatin and oral fluoropyrimidines may offer improved efficacy or patients' convenience in the adjuvant setting and their impact on survival will be evaluated in the recently closed large randomised studies. This review summarises the current status of adjuvant therapy in colon cancer and describes the future directions for research.