Knowledge related to endoscopic examination of rectal cancer

The diagnosis of rectal cancer can be determined through medical history, physical examination, fecal occult blood test, etc., and the diagnosis is mostly based on endoscopic examination. Endoscopic examination of rectal cancer mainly includes proctoscopy, sigmoidoscopy and fiber colonoscopy. Proctoscopy or sigmoidoscopy can be used for routine outpatient examinations. It is easy to operate and does not require intestinal preparation. However, fiber colonoscopy should be performed when surgical treatment is required for the diagnosis of rectal cancer, because 5% to 10% of rectal cancers are multiple cancers. Endoscopic examination can not only make judgments under direct vision with the naked eye, but also take live tissue for pathological examination.

Endoscopy is recommended for all patients suspected of rectal cancer, except for the following: poor general condition and difficult to tolerate;

Acute peritonitis, intestinal perforation, extensive intra-abdominal adhesions and complete intestinal obstruction; perianal or severe intestinal infection, radiation enteritis; women during pregnancy and menstruation.

Before fiber colonoscopy, the intestine must be prepared, and liquid food, laxatives, or cleansing colon must be taken 2 to 3 days before the examination to clear the feces in the intestine. The endoscopic examination report must include examination items such as the depth of entry, size of the tumor, location from the anal verge, morphology, and the range of local infiltration.