There is a certain difference between six and eight cycles of chemotherapy for colon cancer, and eight cycles are more capable of further killing tumor cells. Chemotherapy for colon cancer is a conventional treatment, especially for patients with lymph node metastasis or distant metastasis, most of the chemotherapy courses are 6 to 8 cycles. 8 cycles of chemotherapy can further kill tumor cells, so the therapeutic effect may be better than 6 cycles. However, for patients with earlier staging and lower probability of recurrence and metastasis, adding 2 cycles of chemotherapy cannot improve the prognosis. Therefore, although 8 cycles of chemotherapy can further kill tumor cells, not everyone can benefit from it, and it is necessary to decide the specific cycles of chemotherapy after evaluating the risk of recurrence and metastasis of the patient.