Stage 3 colon cancer is a progressive stage colon cancer, the tumor is large and may invade the muscular layer or break through the muscular layer to reach the subplasma layer, or it may have invaded the plasma layer but not break through to the outer plasma membrane, and there are positive lymph nodes around the tumor, the lymph nodes are relatively large, but the lymph nodes should not be fused into a mass. The main reason is that patients do not have abdominal symptoms in the early stage, or they do not pay enough attention to the symptoms, and only when the tumor has grown or the tumor has metastasized to the lymph nodes do they go to the hospital for examination. After the surgery, chemotherapy is needed, which is combined with capecitabine and oxaliplatin for about 6 months in total, and after the surgery, patients must follow up with the hospital regularly to prevent tumor recurrence or metastasis.