High-grade epitheliomatous neoplasia of the rectum is usually not very serious if it is early and more serious if it enters the middle or late stages. Early stage patients may experience frequent bowel movements, anal swelling, and blood in the stool. High-grade intraepithelial neoplasia belongs to the severe atypical hyperplasia, such as no infiltration into the submucosa, no lymph node metastasis, no infiltration of other tissues, complete removal of the diseased polyp, basically can achieve a curative effect, this situation is usually not very serious. If the patient has already entered the middle or late stage of rectal high-grade intraepithelial neoplasia when discovering the disease, it is very likely that lymphatic or hematogenous metastasis has already occurred at this time, and the possibility of cure is relatively small. After the polypectomy surgery, other auxiliary treatments such as radiotherapy, chemotherapy and targeted therapy are also needed. It is recommended that patients undergo regular medical checkups to detect hidden health problems as early as possible and seek medical treatment in time, which will be conducive to the recovery of the condition and avoid the aggravation of the condition in a delayed manner.