Rectal lesions usually have symptoms such as mucus in stool, constipation, diarrhea and abdominal pain. 1. Stool with mucus: stool with mucus is due to the rectal inflammatory lesions secreted mucus increased, usually by the intestinal bacterial infection is not timely cleaning triggered. 2. Constipation: Constipation means that after the stool reaches the rectum, the bowel can not move due to the slow nerve response, thus causing difficulty in defecation. 3. Diarrhea: diarrhea is mainly caused by inflammation leading to gastrointestinal absorption dysfunction, which stimulates intestinal peristalsis, usually too often. 4. Abdominal pain: Abdominal pain may be caused by the spread of tumor cells causing lesions, which may lead to abdominal pain, or it may be caused by the obstruction of gastrointestinal absorption of metabolite residues. Rectal lesions may also appear with blood in stool, defecation is not shaped and other symptoms, it is recommended that patients go to the hospital in time for examination, to clarify the cause of the disease, and standardize the treatment under the guidance of the doctor.