A colorectal polyp being removed by a colonoscope's snare.

What are polyps, and do they lead to colorectal cancer?

A colorectal polyp being removed by a colonoscope's snare.

Polyps are growths that can occur in different parts of your body, such as your nose, colon, uterus, and stomach. The majority of polyps found in the body are harmless. However, some polyps can be dangerous and may lead to certain cancers, including colorectal cancer. It is important to know the warning signs of polyps, how to seek testing and treatment, increased risk factors, and what role they play in the development of colorectal cancer. 

Understanding the Digestive System

Colorectal cancer is a disease of the digestive system and mostly develops as the result of harmful polyp growths. The digestive system is a group of organs that work together to help our bodies digest and process food. After the food is chewed and swallowed, it goes down to the esophagus and stomach where stomach acids and enzymes break it down.

From there, it moves into the small intestine, where most of the nutrients are absorbed into the bloodstream. The remaining waste travels into the large intestine – otherwise known as the colon – where water is absorbed and waste is turned into stool. 

This waste then leaves the body during a bowel movement. Without our digestive system, our bodies would not be able to get the nutrients we need to stay healthy. 

Warning Signs & Symptoms of Colorectal Polyps

The development of polyps in the colon or rectum has the potential to prevent the digestive system from doing its job. Depending on the size and location of the polyp, it can obstruct the normal flow of stool, causing anemia, constipation, diarrhea, bleeding, or abdominal pain. 

If a polyp is cancerous, it can become a tumor and invade the surrounding tissue, leading to metastatic colorectal cancer. If you experience any changes in bowel habits or ongoing digestive discomfort, you should consult your primary care physician immediately. 

Most people do not have any signs or symptoms of polyps. Therefore, everyone must receive their recommended screenings on time. The Colorectal Cancer Alliance’s Screening Quiz is an easy and quick way to determine your unique screening recommendations. 

Testing for Colorectal Polyps

The good news is there are many ways you can get tested for polyps in the colon and rectum, should you or your healthcare provider have any concerns. 


A colonoscopy is the most effective way to check for colorectal polyps. After receiving an anesthetic – a medicine that helps your body to fall asleep safely – a doctor will use a flexible tube with a camera to examine your entire colon and rectum. If any polyps are found, they can be removed during the procedure and sent off to a lab for further testing.

Flexible Sigmoidoscopy 

The flexible sigmoidoscopy is similar to a colonoscopy procedure, though it only checks the lower part of the colon and rectum. If polyps are found, a colonoscopy will still be needed to remove and test the polyps. 

Virtual Colonoscopy

A virtual colonoscopy uses a CT scan to create a detailed image of the colon and rectum. While it can detect most polyps, it cannot remove them. Therefore, a colonoscopy would still be needed. 

Fecal Blood Test

A fecal blood test checks for blood in the stool. If found, it could indicate polyps and further testing would be required. Follow-up testing for positive fecal results are now covered by insurance. 

Stool DNA Test

The stool DNA test looks for changes in your DNA that would indicate the presence of polyps or cancer. The good news is, insurance is now required to cover follow-up expenses of a positive stool test. 

There are many different options available to test for the presence of polyps. The earlier you catch them, the better the outcome will be. Keep in mind that the majority of polyps are non-cancerous, but some are precancerous. By testing for and removing them, you may be saving yourself from getting colorectal cancer in the future. 

Treatment for Colorectal Polyps

If cancer is found, surgery may be recommended to remove the parts of the colon or rectum that have been affected. Treatment may also include radiation or chemotherapy. Your healthcare provider will work with you to find the best solution. 

The Colorectal Cancer Alliance’s Patient & Family Support Navigators provide free assistance and support to anyone facing a colorectal cancer diagnosis. 

Increased Risk Factors for Colorectal Polyps

Between 15-40% of adults will develop colon polyps, according to the National Institutes of Health. It’s not clear why some people develop colorectal polyps while others do not. However, certain factors have been associated with an increased risk of developing colorectal polyps, including:

  • Age – polyps are more common in people over 50
  • A family history of polyps or colorectal cancer
  • A personal history of inflammatory bowel disease (not to be confused with inflammatory bowel syndrome, which does not pose an increased risk for polyps or cancers)
  • Not getting enough exercise
  • Not eating a well-balanced diet
  • Excessive alcohol consumption
  • Smoking

To decrease your risk factors for developing colorectal polyps and cancer, it is important to lead a healthy lifestyle, talk to your medical provider about any changes or concerns in your digestive health, and get screened. 

How Polyps Become Colorectal Cancer

Most CRC cases develop from adenomatous polyps, which are abnormal growths that can become cancerous if left untreated. The exact mechanism by which polyps turn into CRC is not fully understood, but it is believed to involve a series of changes – or mutations – in the cells that make up the polyp. 

These mutations can cause the cells to grow and divide uncontrollably, leading to the formation of a tumor. Risk factors such as age, family history, and ethnicity can increase the likelihood of developing polyps and CRC. 

If left untreated, polyps can continue to grow and develop into cancerous tumors, which can spread to other parts of the body. The key to preventing CRC is to detect and remove polyps early, before they have a chance to become cancerous. Also, adopting a healthy lifestyle that includes a balanced diet, regular exercise, and avoiding smoking and excessive alcohol consumption can reduce the risk of developing polyps and CRC. 

Get Screened

Because polyps can potentially lead to colorectal cancer, it’s important to complete regular screening tests. People with an average risk of colorectal cancer should begin routine screening at age 45. People with a family history of colorectal cancer and other risk factors may need to begin screening at earlier ages. A doctor can help you determine when to start. 

While colorectal cancer is the fourth most commonly diagnosed cancer in the United States, it is highly preventable and treatable. Polyps are growths that can develop in the body, including the colon and rectum. While some polyps lead to cancer, most polyps are harmless. Still, regular screenings and lifestyle changes can help to reduce the risk of developing colorectal cancer in our lifetime.



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