Why is a colonoscopy so important?

Joseph W. Beets, MD
Colonoscopy is a procedure that involves the insertion of a flexible tube (colonoscope) into the rectum and around to the top of the colon. It is done while patients are asleep.
It is the only tool we have available that allows: 1) direct visualization of the lining of the colon (mucosa), 2) biopsy or sampling of the mucosa, and 3) removal of polyps or growths within the colon. 
It gives us the opportunity to diagnose different diseases, such as colitis, by visualizing specific abnormalities and taking biopsies.

It allows us to treat patients, as polyps and even early cancers can be removed at the time of the procedure.

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Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)

Dr. Oz tells his personal story of a colonoscopy and the results that changed his life. In this video, he talks about why colonoscopies are so important.

Daniel Labow, MD
Surgical Oncology
Colonoscopy is the single best test to detect colon cancer or precancerous colon polyps.  Symptoms may be absent and thus, colonoscopy may be the only way to see and prevent cancer from developing.   Also, if symptoms develop such as bleeding, thinning of the stool, difficulty having a bowel movement, then colonoscopy can help determine why these symptoms have developed and allow for proper treatment.

A colonoscopy is needed for these reasons:

  • For people at risk, colonoscopy is the best test to screen for colon
          cancer, pre-cancerous growths and polyps. If an abnormal growth
          or polyp is found, the doctor can remove it, take a biopsy, or
          recommend surgical removal later. Detecting and removing
          growths may prevent cancer from developing.
  • A colonoscopy also helps your doctor see other problems that may be
          causing abdominal pain, weight loss, or changes in bowel habits.
          This includes ulcers, narrowed areas, inflammation or bleeding.

Colorectal cancer is the second leading cause of cancer deaths among Americans. A colonoscopy is the single most accurate test for colorectal cancer. Importantly, a colonoscopy can identify and remove pre-cancerous lesions (polyps) and thus reduce the risk of developing cancer in the future. 

Mark E. Chisam, MD
Radiation Oncology
Colon cancer is one of the most curable forms of cancer when found early, but in its early stages there are no symptoms. A colonoscopy can detect polyps, which can be removed before they have a chance to become cancerous or before the cancer spreads. When found and treated early, colon cancer can be cured in the vast majority of patients, so it’s important to have a colonoscopy as part of your regular preventive health care.
Colonoscopy plays an important role in preventing colorectal cancer because precancerous polyps can be detected and removed during the same exam when they are discovered. Colorectal cancer, often referred to as colon cancer, develops in the colon or the rectum (known as the large bowel or large intestine). The colon and rectum are parts of the digestive system, which is also called the gastrointestinal (GI) tract. The digestive system processes food for energy and eliminates solid waste. Colorectal cancer usually develops slowly over many years. Most colorectal cancer begins as a noncancerous (benign) adenoma or polyp (abnormal growth) that develops on the lining of the colon or rectum. Polyps can be removed to significantly reduce cancer risk. Colonoscopy is considered the gold standard of colorectal cancer screening methods for its ability to view the entire colon and both detect and remove polyps during the same procedure.
Colonoscopy lets your doctor examine the lining of your large intestine (colon) for abnormalities by inserting a thin flexible tube, as thick as your finger, into your anus and slowly advancing it into the rectum and colon. This instrument, called a colonoscope, has its own lens and light source and it allows your doctor to view images on a video monitor.
Colonoscopy may be recommended as a screening test for colorectal cancer, which is the third leading cause of cancer deaths in the U.S. Annually, approximately 150,000 new cases of colorectal cancer are diagnosed in the U.S. and nearly 50,000 people die from the disease. It is estimated that increased awareness and screening would save at least 30,000 lives each year.
Beginning at age 50, both men and women at average risk for developing colorectal cancer should have a colonoscopy every 10 years. People with risk factors or family history of colorectal cancer should talk with a gastroenterologist about screening sooner and find out how often they need to be screened. Individuals at any age with certain symptoms should speak with a physician. The following symptoms  might indicate colorectal cancer:  Blood in your stools, narrower than normal stools, unexplained abdominal pain, unexplained change in bowel habits, unexplained anemia, and unexplained weight loss. These symptoms may be caused by other benign diseases such as hemorrhoids, inflammation in the colon or irritable bowel syndrome. If you experience any of these symptoms for more than a few days, talk to a gastroenterologist.
Ajay K. Sahajpal, MD
Transplant Surgery
Colonoscopy is a valuable tool for cancer screening and it can also be therapeutic because precancerous lesions or polyps can be identified and removed.  Early identification of a tumor can lead to an increased chance of cure ideally.
Nearly one in every 20 adult Americans will develop colon cancer in his or her lifetime. Research has confirmed that the single best prevention for colon cancer is the early detection and removal of all colon polyps. And the best method for detection and removal is a colonoscopy.

Colonoscopy is a valuable tool for the diagnosis and treatment of many diseases of the large intestine. As a result of the progress made in the field of fiber optics, colonoscopies are now considered a safe, relatively simple and highly effective diagnostic technique. Increased awareness of the value of early diagnosis has made the procedure part of many people’s comprehensive physical examination.

Through the use of colonoscopy, a physician can detect and remove polyps without abdominal surgery and perform biopsies, which may reveal early signs of cancer. In addition, periodic colonoscopy is critical in monitoring patients who have had polyps, colitis or colon cancer or who have a family history of colon cancer.
A colonoscopy is a study in which a small, flexible camera can look at the inside wall of the colon (the large bowel). It also has a biopsy device attached to it so that if there is abnormal-looking tissue or a polyp on the inside of the colon, it can remove a very small amount, which can be sent to pathology. A colonoscopy allows gastrointestinal doctors to be able to diagnose diseases of the colon like Crohn's disease, ulcerative colitis and colon cancer. It also enables them to screen for abnormal tissue in the colon like a polyp, which may be precancerous, and remove it before it turns into cancer.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.