Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Colon polyps are growths on the inner lining of the colon and are very common.
Colon polyps are important because they may be, or may become malignant (cancerous). They also are important because based on their size, number, and
microscopic anatomy (histology); they can predict which patients are more likely to develop
more polyps and colon cancer.
Changes in the genetic material of cells lining the colon are the cause of polyps.
There are different types of colon polyps with differing tendencies to
become malignant and abilities to predict the development of more polyps and
cancer. It is important to recognize families with members who have familial
genetic conditions causing polyps because some of these conditions are
associated with a very high incidence of colon cancer, and the cancer can be
prevented or discovered early.
Only a small proportion of polyps cause symptoms or signs. When they do, the symptoms and signs usually are the result of
bleeding from the polyp
and may include
Colon polyps are treated by endoscopic removal and occasionally by surgery.
Follow-up surveillance of patients with colon polyps depends on the presence of a family history of cancer, the number of polyps that are found, the size of the polyps, and the polyps' histology, and can vary between three and ten years.
Treatments to prevent colon polyps are being pursued actively.
Colon polyps are growths that occur on the inner lining of the large intestine (colon) and
usually protrude into the colon. Polyps form when the genetic material within
the cells lining the colon changes and becomes abnormal (mutates). Normally, the immature cells lining the colon are programmed to divide (multiply), mature, and then die in a very consistent and timely fashion. However, the genetic changes that occur in the lining cells prevents the cells from maturing, and the cells do not die. This leads to an accumulation of immature, genetically abnormal cells, which eventually results in the formation of polyps. The mutations may occur as a sporadic event after birth or they may be present from before birth.
What do colon polyps look like (pictures)?
Most polyps are protrusions from the lining of the intestine.
Polypoid polyps look like a mushroom, but flop around inside the intestine because they are attached to the lining of the colon by a thin stalk.
Sessile polyps do not have a stalk, and are attached to the
lining by a broad base.
Flat polyps are the least common type of colon polyp, and are
flat or even slightly depressed. These may be difficult to identify because they are not as prominent as polypoid or sessile polyps with the commonly-available methods of diagnosing polyps.
Picture of colon polyps and colon cancer (colorectal).
Melanosis coli is a condition usually associated with
chronic laxative use in which dark pigment is deposited in
the lamina propria
(one of the lining layers) of the large intestine
(colon). The pigment d"...