Individual screening of patients with personal or family history of colon cancer or polyps, or patients with an inflammatory condition of the digestive tract, combined with the generalization of mass screening using Hemoccult, have modified the way colon cancer is diagnosed. The optimization of colon surgery, together with adjuvant chemotherapy, has improved the 5- and 10-year survival. The five-year survival rate is now comprised between 90 percent in patients with stage-I colon cancer, and 65-70 percent in patients with stage-III colon cancer. More than half patients suffer from stage-II (T3-T4 N0) or stage-III (TxN+) cancer, and 30 to 40 percent of these patients experience cancer recurrence without adjuvant therapy within 5 years following surgery. In patients with surgically-resected colon cancer, these recurrences are mostly metastatic (liver, lungs, peritoneum), local recurrences remain uncommon. Metastases are secondary to microscopic tumor foci disseminated away from the primary tumor, non detectable before and during surgery. An adjuvant therapy combining oxaliplatin and fluoropyrimidine is clearly indicated in patients with stage-III colon tumor (20-percent improvement of survival without recurrence), and can be considered in stage-III patients. This treatment is not indicated in patients with stage-I tumor.