Understanding the third most common cancer

Colorectal cancer is the third most common cancer in the U.S. for men and women. According to the Centers for Disease Control and Prevention, in 2012 more than 134,784 people were diagnosed with colorectal cancer and nearly 51,516 died from the disease. Adults age 50 and over are most at risk.

Colon cancer includes cancer that starts in the large intestine, also known as the colon, as well as rectal cancer that starts in the rectum. Like other types, colorectal cancer occurs when abnormal cells form tumors in normal tissues.

Identifying the symptoms of colorectal cancer

Early colorectal cancer may not cause any symptoms which is why regular screening is critical. Symptoms that can be associated with colorectal cancer include changes in bowel habits, rectal bleeding, abdominal pain, blood in the stool, weight loss, and fatigue. However, many of these symptoms could be associated with other conditions such as hemorrhoids, inflammatory bowel disease, or infections. If you have any of these symptoms it is important to see your doctor to determine the cause and get treatment if necessary. The good news is that with screening and the removal of precancerous polyps, colorectal cancer is preventable and very treatable in its early stages.

Avoiding risk factors

As with other diseases, there are many factors that increase your risk of developing colorectal cancer, including:

  • An inflammatory bowel disorder or a personal history of cancer
  • A diet high in red meats like beef, pork, or lamb
  • A diet with limited fruits and vegetables
  • Tobacco use
  • Alcohol use
  • Lack of physical activity
  • Excess weight and obesity

Avoiding tobacco, limiting alcohol consumption, eating a diet high in fruits and vegetables, and increasing physical activity may reduce the risk of colorectal cancer. However, the most effective way to reduce your risk of developing colorectal cancer is by getting regular screenings. Most adults should be screened starting at age of 50, unless you have a family history of colon cancer or other risk factors.

Cancer screenings and preventive measures

There are many different types of screenings, but what’s important is that you get tested regularly. Everyone can find a test that is right for them. Here are a few options:

  • A colonoscopy involves a long, flexible viewing tube inserted through the rectum to view the colon in real-time. Colonoscopy is considered the most accurate method in detecting both polyps and colorectal cancer. During the colonoscopy polyps can be removed and tissue samples can be obtained for microscopic analysis.
  • Stool DNA tests are a new, non-invasive test that can screen for colon cancer. This option is ideal for patients who don’t want to undergo the usual preparation required for a colonoscopy but must be performed annually.
  • Double-contrast barium enemas X-ray the colon and rectum where barium and air is administered through the anus into the rectum and colon. This will give a picture of the colon and diagnose tumors or large polyps. Double contrast barium enema is not recommended for screening, however it can be a useful tool in some situations.
  • CT colonography, also known as a virtual colonoscopy, is a scan of the colon that produces images your colon. It can be a helpful tool when a colonoscopy is not possible or incomplete.

Talk with your doctor about which screening test is right for you. He or she will be able to explain all the options and how often you should be screened to stay healthy and prevent colon cancer.


October 7, 2015 | by Ulrik Wallin MD, PhD, MS