Rectal masses may be benign or malignant. Benign masses include diseases such as hemangiomas, rectal polyps, and misshapen tumors, and malignant masses are generally considered to be rectal cancer. Benign masses 1, hemangioma: usually refers to abnormal blood vessels in the form of specific solid tumors, which can occur at any age and increase in size over time, most of which are benign tumors, single or multiple, easily causing gastrointestinal bleeding and endangering patients’ lives, most of which require surgical treatment and can be removed or ablated under colonoscopy; 2, rectal polyp: refers to a type of bulging lesion that protrudes from the mucosal surface into the intestinal lumen. They can be divided into adenomatous polyps and inflammatory polyps according to the nature of the pathology, with clinical manifestations of intestinal irritation, diarrhea or increased number of bowel movements, blood in stool, intestinal obstruction and intussusception, etc. They can be removed by electrosurgical polypectomy under colonoscopy; 3. Malformation tumors: they are tumor-like malformations caused by the wrong arrangement and combination of normal tissues during the development of the body, which increase with the growth and development of the body, but can stop when they increase to a certain extent. It will stop growing to a certain extent and is rarely malignant. The symptoms and treatment methods are the same as those for rectal polyps. The incidence of malignant mass rectal cancer is related to genetic factors, high-fat and low-fiber diet, and poor living habits. Treatment is mainly surgical resection, preoperative and postoperative chemotherapy (5-fluorouracil), radiation therapy, etc. Pre-cancerous lesions of rectal cancer (mainly adenomas) can also be intervened, and timely resection under endoscopy can effectively prevent the development of the disease.