 This study aims to evaluate the safety and efficacy of activated and expanded autologous cytokine-killer cells in controlling disease recurrence in patients with colon cancer. 20 patients with confirmed colon carcinoma who have had complete resection of primary lesions will be randomly assigned into two groups. Patients in both groups will receive the same therapeutic regimen as usual. Patients in one group additionally will be treated with several infusions of autologous killer cells that had been previously prepared from peripheral blood. 