All About Polyps

A polyp is similar to a mole on your skin – a usually benign growth that can develop and change over time. A growth you want to have looked at and possibly removed before it can harm you. Unlike a mole, polyps are inside your colon and can’t be seen without special equipment. Colonoscopies can explore the inside of your colon, looking for these growths, and even remove them before they become dangerous to your health.

Polyps are small growths or bumps that form on the inside walls of your colon (large intestine) or rectum. Over time, about 5-10% of polyps will turn into cancer.

 

Polyps and Colonoscopies 

A colonoscopy is the best way to find and remove polyps before they can turn into cancer. Other methods of screening are not as effective at detecting polyps. If you have a family history of polyps or colorectal cancer, it is important to talk to your doctor about getting screened earlier than usual.

About 1 in 5 adults (20%) have colon polyps, and the risk for polyps is higher for people over 50 years old (about 40%). Kids can get polyps too, though it’s less common; around 6% of children may develop colon polyps. If someone in your family has had polyps or colorectal cancer, you may be at a higher risk of developing polyps, which means you should have a colonoscopy before you turn 45. Learn more about how your family history affects screening.

Polyps usually take about 10 years to turn into early-stage colon cancer. Removing a polyp during a colonoscopy can stop cancer before it starts. All polyps should be removed during a colonoscopy.

Different Types of Polyps

Polyps can be classified by shape.

Pedunculated Polyps

These polyps have a stem or stalk and look like a mushroom. These polyps are easiest to find during a colonoscopy

Sessile Polyps

These are flat or slightly raised dome and can be harder to see during a colonoscopy.

Polyps can also be classified based on whether they can turn into cancer or not.

Neoplastic Polyps

Neoplastic Polyps are polyps that have a high risk of turning into cancer. They include:

  • Adenomas: the most common type of neoplastic polyp. Some adenomas have a higher risk of turning into cancer than others.
    • Tubular Adenomas: These polyps look like tubes and have a lower risk of becoming cancer.
    • Villous Adenomas: These polyps have an irregular shape and a higher risk of becoming cancer.
    • Tubulovillous Adenomas: These polyps are a mix of both tubular and villous types and have an average risk of turning into cancer.
  • Sessile Serrated Polyps: These are flat or slightly raised saw-tooth-like polyps are considered precancerous.
  • Traditional Serrated Adenomas: These look like a saw-tooth pattern and are also considered precancerous.

Non-Neoplastic Polyps

Non-Neoplastic Polyps are not cancerous (benign) and aren’t often a problem. These types of polyps are common in older adults and those with a family history of colon cancer. They include:

  • Hyperplastic Polyps: These are very common and have a very low risk of becoming cancer.
  • Juvenile Polyps: These are more common in children.
    • Most juvenile polyps are benign and not associated with an increased risk of colon cancer. 
    • Juvenile Polyposis Syndrome, however, is a hereditary condition characterized by multiple juvenile polyps and can drastically increase the risk of colon or other GI cancers and should be closely monitored.

After a colonoscopy, your doctor will consider these things when deciding your future risk for polyps and developing colorectal cancer:

  • How many polyps were found
  • The size of the polyps
  • Where the polyps are in your colon (the right side vs. the left side)
  • What type of polyps were found

Polyps grow slowly, so having a few small ones usually means your risk of cancer is still low. If you have larger or more advanced polyps, however, your doctor may want to screen you and your family members earlier than usual.

What Are Advanced Adenomas?

Advanced adenomas are neoplastic polyps that are larger or have certain features that make them more likely to become cancer. These include:

  • Polyps larger than 1 cm (about the size of a small marble)
  • Any adenoma with irregular growth 
  • Sessile serrated polyps larger than 1 cm
  • Any serrated lesion that looks abnormal under a microscope
  • Traditional serrated adenomas, even if they are small

Risk Factors for Colorectal Polyps and Cancer

Some things that could make you more likely to develop colorectal polyps include:

  • Having more than three polyps of any kind
  • Finding polyps larger than 1 cm
  • Having polyps on the right side of your colon (your sigmoid or transverse colon)
  • Finding villous or tubulovillous adenomas
  • Finding serrated lesions (like sessile serrated polyps)
  • Having a genetic condition that runs in your family (like hereditary polyposis syndrome)

My doctor found polyps, now what?

  • The polyps will be send to the lab for testing. 
  • Your gastroenterologist will let you know the results of those tests and how that affects your screening schedule (1, 3, or 5 years until screening your next colonoscopy).
  • Let your immediate family know the test results. If the polyps are considered advanced adenomas (pre-cancerous) your immediate family should begin screening before 45.