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Colorectal Polyps

  • An abnormal but often benign growth that forms on the inner (mucosal) wall of the colon or rectum
  • Symptoms include blood in the stool, anemia, abdominal pain, and changes in bowel habits
  • Treatment involves polyp removal if detected during a colonoscopy
  • Involves Gastroenterology, Surgery

Colorectal Polyps


In the United States, one of the most common gastrointestinal conditions is colorectal polyps—abnormal growths that forms on the inner wall of the colon or rectum. Most polyps are benign (not cancerous). “However, many polyps are precancerous [adenomas], which, if they remain in place for over 5 to 7 years, may progress towards a cancer,” says Yale Medicine’s Harry Aslanian, MD, a Yale Medicine gastroenterologist.  

“The detection and removal of colorectal polyps in a benign state prevents them from ever progressing towards a cancer,” he says. That’s why doctors encourage adults over 50 to have regular screening tests. Individuals with a family history of colon cancer or polyps may benefit from initiating screening sooner.

What are the types of colorectal polyps?

Polyps can occur anywhere in the intestinal tract and are most common in the large intestine (colon and rectum). There are several shapes and types. “Some polyps grow like a mushroom on a stalk [pedunculated polyps] while others may be flat and carpet-like [sessile polyps],” says Dr. Aslanian. “Flat polyps are often harder to detect.”

Polyps are also categorized as neoplastic and non-neoplastic polyps. The neoplastic polyps, also known as adenomas, are the ones that have a chance of becoming cancerous if they remain in place for multiple years. A polyp is considered to be cancerous when abnormal cells spread from the polyp to surrounding tissue.

Who is at risk for developing colorectal polyps?

Colorectal polyps are more common in people who are over 50 and in those who’ve had polyps before, he says. Polyp growth has also been linked to certain habits, such as cigarette smoking, heavy alcohol consumption, a lack of exercise and a high-fat and low-fiber diet.

Colorectal polyps are also associated with the following inherited conditions:

  • Familial adenomatous polyposis (FAP), which causes hundreds or even thousands of polyps to form in the colon.
  • MUTYH-associated polyposis (MAP) syndrome, which is a more recently discovered disorder that resembles FAP.
  • Gardner syndrome, which results in the development of numerous polyps along with other abnormal lesions.
  • Lynch syndrome, which often affects people at a younger age and can lead to problems in other parts of the body.

How are colorectal polyps diagnosed?

Sometimes, the doctor will look for colorectal polyps after a patient has reported certain symptoms such as anemia, abdominal pain or a change in bowel habits.

Most of the time, however, colorectal polyps do not have symptoms, and routine screening is advised even in the absence of any family history or symptoms. Doctors may discover them during one of the following exams:

  • Digital rectal exam, in which the doctor inserts a gloved finger into the rectum to feel for abnormalities.
  • Fecal occult blood test, which is a lab test used to detect invisible blood in the stool.
  • Stool DNA test, which detects DNA from polyps.
  • Colonoscopy, in which the doctor uses a colonoscope, which is a thin, flexible tube with a tiny camera, to examine the entire large intestine. Doctors encourage anyone over 50 to have a colonoscopy every 10 years. 

What is unique about Yale Medicine’s approach to colorectal polyp treatment?

Yale Medicine gastroenterologists, surgeons and oncologists utilize the latest technologies to identify and safely remove colorectal polyps during colonoscopy. “Colorectal cancers are evaluated and treated by a multidisciplinary team of experts who specialize in minimally invasive and state-of-the-art treatment,” says Dr. Aslanian.