Definition A colorectal polyp is an abnormal growth of tissue on the inside lining of the bowel or rectum.
What is going on in the body? Colorectal polyps are very common. They affect about 25% of adults who are 50 years of age and older. They are most often benign, or noncancerous. However, polyps can sometimes develop into colorectal cancer.
What are the signs and symptoms of the condition? Most often, polyps cause no symptoms at all. They are found when a healthcare doctor examines the colon. Rarely, polyps can cause blood in the stools or abdominal distress.
What are the causes and risks of the condition? The exact cause of polyps is not well understood. Sometimes polyps are genetic. Polyps are more common as a person gets older. Diets high in fat and low in fibre are thought to play a role in causing polyps. Alcohol use, cigarette smoking, and obesity may also increase the risk of developing polyps.
What can be done to prevent the condition? Currently, nothing has been shown to definitely reduce the risk of polyps. Diets high in fibre, folic acid and calcium, and low in fat may help to reduce the risk. Nonsteroidal anti-inflammatory medications may also reduce the risk of developing colorectal polyps.
How is the condition diagnosed? Colorectal polyps can be seen only with special tests because polyps are hidden within the body. A barium enema is a special X-ray test that can detect polyps.
Starting at the age of 40, people should have yearly digital rectal examinations and stool testing for occult blood. Annual fecal occult blood tests allow early detection of colorectal polyps. The polyps can then be removed before they become colorectal cancer.
Beginning at the age of 50, a flexible sigmoidoscopy should be done every 3 to 5 years. A sigmoidoscopy is a procedure that allows a healthcare professional to look into the rectum and sigmoid bowel through a flexible scope.
A colonoscopy may also be used to diagnose colorectal polyps. Like a sigmoidoscopy, this procedure allows a healthcare professional to look into the rectum and sigmoid bowel through a flexible scope. The difference between the procedures is that colonoscopy goes further or deeper into the bowels than sigmoidoscopy.
What are the long-term effects of the condition? Colorectal polyps sometimes become colorectal cancer. Occasionally, a polyp actually is a small, early cancer.
What are the risks to others? Colorectal polyps are not contagious and pose no risk to others.
What are the treatments for the condition? When polyps are seen with a barium enema X-ray test, the person may need a sigmoidoscopy or colonoscopy. During these procedures, the doctor can sometimes remove or destroy polyps through the tube. Otherwise, the doctor may cut off a small piece of the polyp for a biopsy to be looked at under a microscope.
In some cases, a portion of the bowel is removed surgically, with a colostomy. This is usually done if the polyp is large, or if the biopsy looks suspicious under the microscope.
What are the side effects of the treatments? Colonoscopy and sigmoidoscopy involve a risk of tearing a hole in the bowel, bleeding, and infection. This risk is increased when biopsies are taken. Any surgery involves a risk of infection, bleeding, and allergic reaction to anaesthesia.
What happens after treatment for the condition? After a polyp is treated, the person can generally go back to his or her normal activities. The doctor will recommend a follow-up plan based on the type of polyps a person has.
How is the condition monitored? All persons are advised to have regular screening for colorectal polyps and colorectal cancer after the age of 50. Those with polyps will need more frequent future screenings with either colonoscopy or barium enema.
Author: Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
