Colon Polyps
All colon and rectal polyps should be removed and tested to detect cancer and help prevent it from forming.

Because there is no way to predict whether a polyp will become cancerous, all polyps should be removed.

Colon polyps are growths that develop on the inner lining of the colon (the longest part of the large intestine). When polyps are present in the rectum (the last part of the large intestine), they are called rectal polyps.

The majority of polyps are harmless (not cancerous); however, some polyps can become malignant (cancerous) over time as cells begin to grow abnormally and invade more of the colon and rectum.

To be safe, all colon and rectal polyps should be removed and tested to detect cancer and help prevent it from forming.

What are the different types of colon polyps?

Colon and rectal polyps are classified into two types based on lab (histopathological) results:

  1. Hyperplastic polyps: Although the risk of cancer is still present, hyperplastic polyps are usually benign and do not become cancerous.
  2. Adenomatous polyps: Adenomatous polyps are much more likely to become cancerous and are more common.

Polyps in the colon and rectal area can grow for years without causing symptoms.

  • Some people may develop symptoms such as rectal bleeding.
  • Polyps can become malignant or cause cramping and abdominal pain as they grow. 
  • Large benign polyps can secrete a lot of mucus, resulting in loose, frequent stools. 

Polyps are found in about one-third of all adults older than 60 years, and their prevalence increases with age. All colon polyps, however, should be detected and removed to prevent the development of colon cancer and any type of discomfort.

Screening for colon and rectal polyps includes:

  • Many rectal polyps can be detected in the office using a digital rectal exam or flexible sigmoidoscopy.
  • Polyps are diagnosed using a colonoscopy to examine the colonic lining directly or using an X-ray with a virtual colonoscopy or barium enema.
  • During a colonoscopy, your doctor will look for changes in the colon lining and remove anything that appears suspicious or abnormal.

What are the treatment options for colon polyps?

Treatment options for colon polyps include:

Polypectomy

  • During a colonoscopy, a wire loop is passed through a colonoscope to remove a polyp. Using an electric current, the wire loop separates the polyp from the colon.
  • The polyp tissue is then sent for further examination (biopsy).
  • Most polyps can be easily and safely removed during your colonoscopy.
  • A colonoscopy can prevent the development of cancer by removing polyps before they become cancerous.

If a polyp is too large, it may require surgical intervention. A polyp can be removed by further procedures such as

Colectomy or colorectal resection

  • Resection is the surgical removal of a portion or all the large intestine.
  • Some polyps are amenable to transanal excision such as transanal endoscopic microsurgery.
  • If available, traditional techniques may be recommended for minimally invasive removal.
  • If the polyp is higher in the rectum, it can be removed using a new technique known as transanal minimally invasive surgery.

Proctocolectomy

  • If you have a rare inherited syndrome such as familial adenomatous polyposis, you may require surgery to remove your colon and rectum.

The polyp is removed through the rectum under general anesthesia with minimal discomfort and a quick recovery. This is frequently done as an outpatient or inpatient procedure.

People who have had polyps in the past are more likely to develop polyps again in their lifetime and should have regular exams by a physician who is specially trained to treat diseases of the colon and rectum.

IMAGES

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Can all adenomatous polyps cause colon cancer?

When examined under a microscope, an adenoma polyp is composed of tissue that resembles the normal lining of the colon, but it differs in several important ways:

  • Adenoma polyps grow in various ways and are classified as such when they are examined in a lab and reported back to the person.
  • The growth pattern can help determine when additional screening is required. A pathology report generated from the examination of a polyp may contain various terms.

Understanding the meaning of the following words can assist a person in better comprehending what was discovered:

  • Tubular and villous:
    • These are the two most common growth patterns discovered.
    • The tubular pattern is found in the majority of adenomas that are less than half an inch.
    • Larger adenomas may develop in a villous pattern. Cancer frequently develops in larger adenomas with a villous pattern.
      • Tubular adenoma: 5 percent risk of cancer
      • Tubulovillous adenoma: 20 percent risk of cancer
      • Villous adenoma: 40 percent risk of cancer
  • Sessile:
    • These are polyps that grow as slightly flattened spheres with a broad base.
  • Serrated:
    • Under a microscope, adenoma polyps have a saw-toothed appearance.
    • These growths are classified as sessile serrated or traditional serrated.
    • These polyps are not cancerous, but they are precancerous, which means they have the potential to become cancerous.
  • Dysplasia: Polyps with dysplasia (abnormal microscopic appearance of the cells) come in two different degrees:
    • A polyp with low-grade dysplasia does not resemble cancer.
    • High-grade dysplasia is more abnormal and resembles cancer. If high-grade dysplasia is discovered, a repeat colonoscopy may be required sooner than usual.

Depending on the size of polyps:

  • <1 cm: <1 percent risk of cancer
  • 1 to 2 cm: 10 percent risk of cancer
  • >2 cm: 15 percent risk of cancer

People who have an adenoma polyp will need to have follow-up colonoscopies to ensure that no more polyps form. The number of polyps discovered at one time, as well as the pathology details of the polyp, determine the timing of the next colonoscopy.

5 common symptoms of colon polyps

Because most people with colon polyps have no symptoms, you may not realize you have one until your doctor discovers it during a colonoscopy.

Some people with colon polyps may experience the following symptoms:

  1. Rectal bleeding: This could be a sign of colon polyps, cancer, or other conditions such as hemorrhoids or tears in the anal wall.
  2. Change in stool color:
    • Blood can appear in your stools as red streaks or black spots.
    • Certain foods, medications, or dietary supplements may cause a color change.
  3. Change in bowel habits:
    • Long-term constipation or diarrhea may indicate the presence of a larger colon polyp or cancer.
    • Changes in bowel habits can, however, be caused by various other conditions.
  4. Pain: A large polyp in your colon can partially obstruct your bowel, causing crampy abdominal pain.
  5. Iron deficiency anemia:
    • Polyp bleeding can occur gradually over time, with no visible blood in your stools.
    • Chronic bleeding depletes your body's supply of iron, which is required to produce hemoglobin (the substance that allows the red blood cells to transport oxygen throughout your body).
    • As a result, you may experience fatigue and shortness of breath due to iron deficiency anemia.

See your doctor if you experience the following:

  • Abdominal pain
  • Blood in your stools
  • A change in your bowel habits that lasts longer than a week

QUESTION

What are risk factors for developing colon cancer? See Answer

What causes colon polyps?

Certain gene mutations can cause the cells to divide even when new cells are not required. 

Polyps can form due to uncontrolled growth in the colon and rectum, as well as anywhere in the large intestine. In general, the greater the size of a polyp, the greater the risk of cancer.

Six risk factors for colon polyps include:

  1. Age:
    • The majority of people with colon polyps are older than 50 years.
  2. Inflammatory intestinal conditions:
  3. Family history or hereditary conditions:
    • If you have a parent, sibling, or child who has colon polyps or cancer, you are more likely to develop them as well.
    • If you have a large number of family members who have them, your risk is increased.
    • Some hereditary conditions may increase the risk of polyps and cancer.
  4. Smoking and excess alcohol use:
    • An analysis of eight studies reported that people who drank three or more alcoholic drinks per day had a higher risk of colon polyps.
    • The combination of alcohol and smoking appears to increase the risk of colon polyps.
  5. Obesity, lack of exercise, and fat intake:
    • According to research, all these factors can increase your risk of polyps.
    • However, increasing your fiber intake and exercising regularly can lower your risk.
  6. Ethnicity:
    • African Americans are more likely to develop colon cancer.

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How can I prevent colon polyps?

Regular screenings can significantly reduce your risk of colon polyps and colorectal cancer. Moreover, certain lifestyle changes can be beneficial.

  • Healthy habits:
    • Reduce your fat intake by eating plenty of fruits, vegetables, and whole grains.
    • Limit your alcohol consumption and abstain from all tobacco products.
    • Maintain a healthy body weight by remaining physically active.
  • Calcium and vitamin D:
    • Calcium supplementation helps prevent the recurrence of colon adenomas. However, it is unclear whether calcium has any anticancer properties.
    • Other research has indicated that vitamin D may have a protective effect against colorectal cancer.
  • Take care of risk factors:
    • Consider genetic counseling if you have a family history of colon polyps.
    • If you have a hereditary disorder that causes colon polyps, you will need regular colonoscopies beginning in your 20s.

Colorectal cancer treatment has advanced dramatically in recent decades.

  • People must understand that current regimens are usually very well tolerated by the person, with very few side effects.
  • As a result of significant advances in the colon and rectal cancer treatment, there are now more than 1.5 million colorectal cancer survivors in the United States alone.
  • This is a remarkable statistic that would not be possible without raising colorectal cancer awareness and emphasizing the importance of colon polyp screening and colonoscopy.

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Medically Reviewed on 1/12/2022
References
Image Source: iStock Images

Understanding Polyps and Their Treatment: https://www.asge.org/home/for-patients/patient-information/understanding-polyps

Patient education: Colon polyps (Beyond the Basics): https://www.uptodate.com/contents/colon-polyps-beyond-the-basics/print

Polyps of the Colon and Rectum: https://fascrs.org/patients/diseases-and-conditions/a-z/polyps-of-the-colon-and-rectum

Treatment for Colon Polyps: https://www.niddk.nih.gov/health-information/digestive-diseases/colon-polyps/treatment

Colon Polyps: https://gi.org/topics/colon-polyps/