Colorectal cancer is the third most common type of cancer in the United States, excluding skin cancers. It’s also the second leading cause of death from cancer, according to the American Cancer Society. When found early, colorectal cancer often can be cured.
In fact, 90% of people diagnosed with colorectal cancer before it has spread live at least five years. The best way to find cancer early is with regular screenings. A colonoscopy is one of the most common screening tests for colorectal cancer. So, who needs a colonoscopy and when?
What Is a Colonoscopy?
A colonoscopy is an exam used to detect changes or abnormalities in the colon (large intestine) or rectum. You’ll be sedated so that you sleep through the whole procedure, which involves inserting a large, flexible tube through the rectum to examine the lining of your colon. In addition to looking for signs of cancer, the procedure looks for polyps, ulcers, and inflammation. Any polyps your doctor sees can be removed and tested for cancer.
For many people, preparing for the test is the worst part of having a colonoscopy, but it’s also the most important part. You will be given dietary instructions to follow a day or two before the procedure. The night before the procedure you will take a laxative or drink a prep solution to clear your bowels. It’s very important to follow these instructions carefully so your doctor has a clear view of your colon.
Who Needs a Colonoscopy?
Everyone is at risk for colorectal cancer, and that risk increases with age. For people at average risk of developing colon cancer, the U.S. Preventive Services Task Force recommends colonoscopy screenings beginning at age 50. With an increasing number of people under age 50 being diagnosed with colon cancer, the American Cancer Society recommends starting screenings at age 45.
People at higher risk for colon or rectal cancer should consider starting screening at age 45 or earlier. Cancer.net recommends you start screening earlier than age 45 if you have a:
- parent, sibling, or child who has had colorectal cancer or colon polyps
- personal history of colon or rectal cancer or certain polyps
- history of chronic inflammatory bowel diseases such as Crohn’s or ulcerative colitis
- genetic syndrome such as familial adenomatous polyposis
Your doctor may recommend that you have a colonoscopy every 10 years until age 75. After age 75, discuss with your doctor whether to continue having a colonoscopy. The life-saving benefits of a colonoscopy start to lessen after age 75.
Any screening test has a risk of false positives. This means the exam finds something that seems like cancer but isn’t. That can lead to anxiety and additional tests, such as blood tests, biopsy, or more imaging. However, the benefits of early detection outweigh the risk of false positives.
Does Colonoscopy Save Lives?
Colorectal cancer screenings save lives by finding cancer early — and even preventing it. A colonoscopy can find precancerous polyps, or growths, in the colon. The doctor doing the colonoscopy, usually a gastroenterologist, can these growths before they become cancerous, according to the Centers for Disease Control and Prevention.
Finding cancer early also leads to an increased chance of survival, according to the American Cancer Society. The five-year survival rate for early-stage colon cancer (when it’s only in the colon) is as high as 90%. However, the five-year survival rate drops to only 14% when the cancer is found at the latest stage and throughout the body.
Surgery is the most common treatment and may include the removal of part of the colon or rectum. Finding colon cancer early can lead to less invasive treatment. If the cancer spreads beyond the colon, it’s harder to remove the cancerous tissue. More extensive surgery and/or chemotherapy or radiation may be required.
Treatment has the best outcome when started early. Your doctor can inform you about your risk for colorectal cancer and when you should begin screening.
(Source: UPMC Health Beat)