Colon cancer is a common malignant tumor of the gastrointestinal tract occurring at the junction of the rectum and sigmoid colon, with the highest incidence in the age group of 40 to 50 years old, and the ratio of men to women is 2 to 3:1. The incidence rate is the third highest among gastrointestinal tumors. Colon cancer is mainly adenocarcinoma, mucinous adenocarcinoma and undifferentiated cancer. The general morphology is polyp-like, ulcerated and so on. Colon cancer can develop along the circumference of intestinal wall, spread up and down along the longitudinal path of intestinal tube or infiltrate deeply into the intestinal wall. In addition to metastasis and local invasion via lymphatic vessels and blood stream, it can also spread and metastasize into the abdominal cavity or along the suture and incision surface. Patients with chronic colitis, colon polyps and male obese people are the susceptible groups. Colon cancer examination methods 1.Anal tube finger diagnosis and rectoscopy Check whether there are rectal polyps, rectal cancer, internal hemorrhoids or other lesions. 2.Sigmoidoscopy and fiberoptic colonoscopy can detect cancer and observe its size, location and local infiltration range. 3.Plain abdominal film Suitable for cases of acute intestinal obstruction, with inflation and distension of the colon above the obstruction site. 4.Barium enema It can be seen that the intestinal wall at the cancer site is stiff, poorly dilated, peristalsis is weakened or disappeared, irregular shape or disappearance of colonic pouch, narrowing of intestinal lumen, disorder, destruction or disappearance of mucosal folds, filling defect, etc. Barium air double contrast imaging is more helpful for the diagnosis of tumors with tissues in the colon. 5.Cancer embryonic antigen (CEA) has little diagnostic value for early stage tumors, but it is helpful for speculating prognosis and judging recurrence. Endoscopic minimally invasive treatment can be adopted for lesions that can be radically treated under endoscopy in early stage colon cancer. The treatment method for middle and late stage cancer is a comprehensive program based on surgery, supplemented by chemotherapy, immunotherapy, traditional Chinese medicine and other supportive treatments to improve the surgical resection rate, reduce the recurrence rate and increase the survival rate. The principles of surgical treatment: try to cure radically, protect pelvic vegetative nerves, preserve sexual function, urinary function and defecation function, and improve survival quality.