Colon Adenomatous Polyp



  • Colon: The section of the large intestine leading to the rectum.
  • Adenoma: A benign tumor originating in a glandular (tubular) structure.
  • Polyp: A benign tumor found in the colon. Polyps can become cancerous if undetected or ignored.
  • Benign: Not cancerous.
  • Malignant: Cancerous and capable of spreading.
  • Pathologist: A physician who examines tissues and fluids to diagnose disease in order to assist in making treatment decisions.

What is a colon adenomatous polyp?

Polyps begin in the cells of glandular structures lining the colon. Most polyps are benign, but one kind is the cause of greater concern–the colon adenomatous polyp (adenoma). This growth is associated with DNA changes in the lining of the colon. Up to 10 percent of these polyps can become cancerous within a 10-year period if undetected or ignored. For individuals with multiple polyps, the chance of at least one of these polyps becoming cancerous is very high. However, if malignant polyps are detected early, 90 percent of patients survive at least five years.

Who is most likely to have colon adenomatous polyps?

Some individuals have a genetic tendency to develop polyps. Conditions such as familial adenomatous polyposis or Gardner’s syndrome can cause hundreds of polyps to form in the colon or rectum. Individuals age 50 or older have a higher risk of developing colon adenomatous polyps. In addition to genetic factors, these polyps are associated with a diet high in fat and beef and low in fiber. Another risk factor is a lack of exercise resulting in weight gain.

What characterizes colon adenomatous polyps?

Colon adenomatous polyps grow slowly but will continue to grow if not detected and removed. The larger the polyp grows, the greater the chance it will contain cancerous cells. There are two types of polyps–flat ones that lie against the intestinal wall and mushroom-shaped ones. The flat polyps are more likely to become cancerous.  As the polyp grows, symptoms become more likely and can include rectal bleeding, fatigue, changes in bowel habits, abdominal discomfort, anemia, or bowel obstruction.

How does the pathologist make a diagnosis?

Because most colon adenomatous polyps do not present symptoms, most are found during regular physician examinations. Sometimes, polyps can be felt through a digital rectal exam (DRE), in which a primary care physician inserts a lubricated, gloved finger into the patient’s rectum. Other tests that can detect polyps include a blood test, colonoscopy, flexible sigmoidoscopy, or double-contrast barium enema.

Once a polyp is found, it is removed through colonoscopy or flexible sigmoidoscopy. If the polyp is advanced, a biopsy may be performed as part of surgery. A pathologist closely examines the polyp cells–known as a biopsy sample–under a microscope in the laboratory to determine whether the polyp is cancerous.

What else does the pathologist look for?

The pathologist notes the size of the polyp and whether or not it contains cancerous cells. If it is cancerous, the pathologist makes a diagnosis–most likely colon adenocarcinoma–and notes how close the cancer is to the edge of the removed tissue, and whether the tumor invaded blood or lymphatic vessels. These factors help determine the likelihood of the cancer remaining in or returning to the affected area. In some situations, your primary care physician or specialist may order imaging tests including a chest x-ray or CT scan to see if the tumor has spread to the lungs, lymph nodes, liver, or ovaries.

How do doctors determine what surgery or treatment will be necessary?

The pathologist consults with your primary care physician or specialist after reviewing the test results. Together, using their combined experience and knowledge, they determine treatment options most appropriate for your condition.

What kinds of treatments are available for colon adenomatous polyps?

Benign polyps are removed through colonscopy, flexible sigmoidoscopy or open surgery. In most cases, colonoscopy is the preferred method because the entire colon can be viewed during this procedure and polyps can be removed at the same time. With flexible sigmoidoscopy, a primary care physician or specialist can remove polyps but can only view the lower section of the colon and the rectum. Sometimes, if polyps are very large or difficult to reach, open surgery is necessary to remove them.

If a polyp is cancerous, it is treated with surgery, chemotherapy, or radiation therapy or with a combination of two or three of these treatments. It’s important to learn as much as you can about your treatment options and to make the decision that’s right for you. The most common treatment for malignant polyps is surgery, which can remove the cancerous tumor from the body. Surgery is generally recommended for 90 percent of colon cancer patients. A radical bowel resection–also known as a partial colectomy or hemicolectomy–is the type of surgery performed on most patients.

How can I help prevent polyps from turning cancerous?

To prevent polyps from becoming cancerous, you must have them removed. Toward this goal, regular screenings for polyps are necessary. If you have a family history of any of these conditions–polyps, colon cancer, Gardner’s syndrome, or inflammatory bowel disease–consult with your primary care physician about the optimal timing and frequency for these screenings. Otherwise, you should begin these screenings at age 50. These screenings include periodic DREs, blood tests, and either a flexible sigmoidoscopy or colonoscopy.

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How can I lower the chances of developing polyps?

You can lower the chances of developing polyps by adopting a healthy diet and lifestyle. Fruits, vegetables and whole grains–especially those with high fiber content–are recommended. You should limit your intake of high-fat foods and exercise for at least 30 minutes several times a week.

Following this regimen will help you to achieve an optimal, healthy weight. Other factors that may help reduce the risk of polyps include taking folic acid (found in most multivitamins) and calcium (found in low-fat dairy products and nutritional supplements) and not smoking. If you are at high risk for developing polyps, your primary care physician may recommend other therapies, such as anti-inflammatory drugs or hormonal replacement therapy.

What kinds of questions should I ask my doctors?

Ask any question you want. There are no questions you should be reluctant to ask. Here are a few to consider:

  • Please describe the condition I have and what treatment options are available.
  • What are the chances for my condition turning into cancer?
  • What treatment options do you recommend? Why do you believe these are the best treatments?
  • What are the pros and cons of these treatment options?
  • What are the side effects?
  • Is your medical team experienced in treating the condition I have?
  • Can you provide me with information about the physicians and others on the medical team?
  • If I want a second opinion, will you provide me with the names of physicians or institutions that you recommend?