While uncommon in 20 year olds, more than 40% of persons over 50 have precancerous polyps in the colon.
Colon polyps are extremely common among adults 50 years of age and older, occurring in over 40 percent of individuals who undergo screening colonoscopy.
Aging — Polyps and colorectal cancers are uncommon before age 40. Ninety percent of cases occur after age 50, with males somewhat more likely to develop polyps than females; therefore, colon cancer screening is usually recommended starting at age 50 for both sexes.
Factors that might cause colon polyps or cancer include: Age. Most people with colon polyps are 50 or older.
Anywhere between 15 and 40 percent of adults may have colon polyps. Colon polyps are more common in men and older adults.
Colon and rectal polyps occur in about 25 percent of men and women ages 45 and older. Not all polyps will turn into cancer, and it may take many years for a polyp to become cancerous. Anyone can develop colon and rectal polyps, but people with the following risk factors are more likely to do so: Age 45 years and older.
As often as 40% of the time, a precancerous polyp — frequently a type called an adenoma — is found during a screening colonoscopy. Colon cancer is found during only in about 40 out of 10,000 screening colonoscopies, Dr. Sand said.
If the colonoscopy finds one or two small polyps (5 mm in diameter or smaller), you are considered at relatively low risk. Most people will not have to return for a follow-up colonoscopy for at least five years, and possibly longer.
Polyp Growth Rates
Cancerous polyps tend to grow slowly. It is estimated that the polyp dwell time, the time needed for a small adenoma to transform into a cancer, may be on average 10 years (17).
Anyone can develop colon polyps, and about 6% of children have them. However, the risk of colon polyps and colon cancer increases with age. About a third of people over 50 have polyps. More than 95% of colon cancer begins with colon polyps.
Polyps are very common in adults, particularly older adults. In fact, an average 60-year-old who doesn't have any risk factors still has a 25 percent chance of developing polyps.
Polyps are one of the most common colorectal conditions, occurring in 15 - 20 percent of the adult population. They can occur anywhere in the large intestine or rectum, but are more commonly found in the left colon, sigmoid colon, or rectum.
Someone with just one or two small polyps is generally at lower risk of having or developing colon cancer than someone with three to nine, or more.
[A text version of this figure is available.] The percentage of adults aged 50 to 75 years who reported being up to date with CRC screening in 2020 was 69.4%, representing 62.3 million age-eligible adults, ranging from 58.4% in California to 79.6% in Maine (Map B).
Regular screening, beginning at age 45, is the key to preventing colorectal cancer and finding it early. The U.S. Preventive Services Task Force (Task Force) recommends that adults age 45 to 75 be screened for colorectal cancer. The Task Force recommends that adults age 76 to 85 talk to their doctor about screening.
Although most polyps are benign, they can become cancerous if left untreated. Therefore, it's important to remove these polyps before they become cancerous. A colonoscopy is one of the best ways to detect and remove polyps. It also allows doctors to check for signs of colorectal cancer and remove any abnormal tissue.
Don't worry. Most polyps aren't cancer. But some types of colon polyps do increase your risk of developing colonrectal cancer. So, it's important to be informed.
As polyps slowly grow, however, the cancer risk rises. It's estimated that it takes about 10 years for cancer to form into a colorectal polyp.
Colorectal cancer can occur without polyps, but it is thought to be an uncommon event. Individuals with long-standing inflammatory bowel diseases, such as chronic ulcerative colitis and Crohn's colitis, are at increased risk for developing colorectal cancer that occurs in the absence of obvious polyps.
While the majority of colon cancers start as polyps, only 5-10% of all polyps will become cancerous. The size of a polyp typically does make a difference. The larger the polyp becomes, the bigger the risk of it developing into colon cancer.
Most colon polyps can be removed during a colonoscopy. That's one reason doctors like colonoscopies so much.
Colonoscopic polypectomy is the best diagnostic and therapeutic tool to detect and prevent colorectal neoplasms. However, previous studies have reported that 17% to 28% of colorectal polyps are missed during colonoscopy.
Symptoms of bowel polyps
But some larger polyps can cause: a small amount of slime (mucus) or blood in your poo (rectal bleeding) diarrhoea or constipation. pain in your tummy (abdominal pain)
Smoking, obesity, diabetes, and inadequate exercise are risk factors for polyps, but many people with none of these risk factors have precancerous polyps in the colon. There are genetic risk factors for developing polyps as well.