Polyps are one of the most common conditions affecting the colon and retcum, occuring in 15-20% of the adult population.
What are polyps?
Polyps are abnormal growths in the lining of the large intestine (colon) which protrude into the intestinal canal. Polyps vary in shape, size, number and location within the colon. Some polyps are carpet-like, spreading over the mucosal surface of the bowel. Some have a short stalk or pedicle.
There are different varieties of polyps. Adenomatous polyps (adenomas) can undergo malignant change to produce bowel cancer. Therefore anyone who has had adenomas is at increased risk of developing bowel cancer. Most polyps are benign.
Who is at risk of developing polyps?
People who have suspicious bowel symptoms (especially bleeding) and are approaching 50 years of age or older may need a colonoscopic examination.
Other people at risk include those with a family history of one or more first degree relatives (mother, father, sister, brother or child) who have had bowel cancer and to a lesser extent those with second degree relatives (aunts, uncles, grandparents) who have had bowel cancer.
Patients who have had a previous adenoma or cancer successfully treated have a risk of developing polyps which continues through their life. Familial Adenomatous Polyposis (FAP) is a rare inherited disorder in which some members of the family will develop hundreds of polyps ultimately causing bowel cancer if not treated properly.
People 50 years and over who have no symptoms or family history are still at risk and are strongly advised
What are the symptoms?
Although polyps are very common, they rarely produce symptoms and usually are discovered by chance at the time of colonoscopy or X-ray of the bowel. Larger polyps, however, may occasionally cause bleeding, usually as bloody mixed in the stool, mucus discharge, alteration in bowel function or in rare cases abdominal pain.
How are polyps detected?
Polyps can be found and removed at colonoscopy. Alternatively, the colon can be indirectly examined with x-rays, using CT colonography, but any polyps found must be removed by colonoscopy.
Although checking the stool for microscopic blood is an important test for colon and rectal disorders, a negative test does not rule out the presence of polyps. The discovery of one polyp necessitates a complete colonoscopy since additional polyps will be found at 30% of the time.
How are polyps treated?
Since there is no foolproof way of predicting whether or not a polyp is or will become malignant, total removal of all polyps is advised. The vast majority of polyps can be removed by snaring with a wire loop passed through the colonoscope. Small polyps can be destroyed simply by touching them with a coagulating electrical current. Up to 95% of polyps can safely and completely removed by colonoscopy.
Most colonoscopic examinations, including polyp removal, can be performed on an outpatient basis with minimal discomfort. Large polyps may require more than one treatment for complete removal. Some polyps cannot be removed because of their size or position; surgery is then indicated.
Once a polyp is completely removed its recurrence is very unusual. However, the same factors that cause the polyp to form are still present. New polyps will develop in at least 30% of people who have previously had polyps. For this reason colonoscopy is recommended. The frequency of the examinations varies and your Surgeon will discuss this with you.