How long does it take for precancerous polyps to turn into cancer?
It is believed to take about 10 years for a small precancerous polyp to grow into cancer. Therefore, if appropriate colorectal cancer screening is performed, most of these polyps can be removed before they turn into cancer, effectively preventing the development of colon cancer.
Although most colorectal polyps do not become cancer, virtually all colon and rectal cancers start from these growths. People may inherit diseases in which the risk of colon polyps and cancer is very high. Colorectal cancer may also develop from areas of abnormal cells in the lining of the colon or rectum.
- Mutations in certain genes can cause cells to continue dividing even when new cells aren't needed. In the colon and rectum, this unregulated growth can cause polyps to form. Polyps can develop anywhere in your large intestine.
- Large polyp. This image of the inside of the colon shows a large polyp. Large polyps are 10 millimeters (mm) or larger in diameter (25 mm equals about 1 inch).
- 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.
Updated: 2nd October 2019