Rectum surgery is essentially required when treating rectum cancer or large polyps of the rectum which cannot be removed by endoscopy because of high risks (hemoragy or perforation). This does not include common anal interventions for anus pathologies (hemorroids, fissures, fistulas, abscesses, lower rectum polyps and small lower rectum cancers, according to specific criteria).
This surgery has improved considerably throughout the last 30 years: at the time, rectum surgery usually implied the complete removal of the rectum and anus, and the creation of an artificial anus (stoma) near the bottom left area of the abdomen (rectum amputation).
Nowadays this operation is rarely advised, and only in cases of very low cancers, close to the anus, with invasion of the anal sphincter, or in the case of repeated anorectal epidermoid carcinoma (form of anal cancer) whose usual primary treatment is currently radio chemotherapy (which heals 90% of cases).