Find an ACG member gastroenterologist with a specialized interest in liver disease. The rectum refers to the last four or five inches of the digestive tract. The rectal outlet or opening is called the anal canal or anus. Problems in this area are common, but many adults are too shy or embarrassed to ask their doctor about them. Fortunately, most of these problems are treatable when recognized early and properly diagnosed. Remember that symptoms of rectal pain or bleeding should always be thoroughly evaluated by your doctor.
Anatomy of the Anus | Saint Luke's Health System
Medically reviewed by Drugs. Last updated on May 13, Hemorrhoids are lumps or masses of tissue in the anus, which contain enlarged blood vessels. Any increase in abdominal pressure may produce hemorrhoids. This may be from:. Internal hemorrhoids. Internal hemorrhoids lie inside the anal canal, where they primarily cause the symptom of intermittent bleeding, usually with bowel movements, and sometimes mucous discharge.
What Is Anal Cancer?
The anus is that part of the intestinal tract that passes through the muscular canal of the pelvis and anal sphincters. It is the final orifice through which stool passes out of the body. In adults, the anus is 4 to 5 centimeters long. The lower half of the anal canal has sensitive nerve endings. There are blood vessels under the lining, and in its mid portion there are numerous tiny, anal glands.
Anal cancer is a type of cancer that forms in tissues of the anus. The anus is the opening of the rectum to the outside of the body and at the end of the GI tract. Sometimes anal cancer causes no symptoms at all. But bleeding is often the first sign of the disease.