Colon cancer is often classified into ulcerative, mass, and infiltrative types according to the general morphology of the tumor. Its severity usually needs to be judged according to the extent of tumor infiltration, the presence or absence of lymph node metastasis and distant metastasis. 1. Ulcerative type: more than half of colon cancers are ulcerative type, in which the tumor infiltrates deep tissues to form ulcers and bleeds easily; this type has low differentiation, early metastasis and poor prognosis. 2. Mass type: the tumor grows prominently into the intestinal lumen, there may be ulcers on the surface of the tumor when it enlarges, and there is less invasion to the surrounding tissues, so the prognosis of this type is better. 3. Infiltrative type: the tumor is diffusely infiltrated in all layers of the intestinal wall, the invaded intestinal wall is thickened and the intestinal lumen is narrowed; this type has a low degree of differentiation, and the metastasis is early and the prognosis is poor. The prognosis of colon cancer is better than that of late-stage cancer. Therefore, all suspicious symptoms should be actively diagnosed and treated, so as to avoid the progression of the disease and affect the prognosis.