2016-06-16 17:20:44 UTC

Colorectal Cancer (CRC) 101: What is Colorectal Cancer?

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  • Colorectal cancer (also known as colon cancer) is cancer of the colon and/or rectum and occurs when a growth in the lining of the colon or rectum becomes cancerous
  • The colon is a vital organ in your body’s digestive system. The rectum is the very end of the colon. The colon and rectum, known as the large intestine, is a long, thick tube that:
    • Takes in water and minerals from digested food. 
    • Stores undigested solid waste. 
  • Most colorectal cancers come from precancerous polyps — adenomatous polyps or serrated polyps — that form over a number of years (five to 10) to become a cancer. 
    • A polyp is a mushroom-like or flat growth on the inside wall of the colon or rectum. Polyps grow slowly over many years. 
  • Not all colon polyps have the same risk of turning into colon cancer. Precancerous polyps could become cancerous; other types of polyps (hyperplastic, inflammatory) do not. 
  • If caught early before any symptoms arise, surgery can cure colorectal cancer. Finding colorectal cancer early leads to easier treatments and higher survival rates.


Who Gets Colorectal Cancer?


  • As of 2015, colorectal cancer is the third-most common cause of cancer in both men and women. It is the second-leading cause of cancer deaths in the U.S.
  • While men and women have the same lifetime risk for CRC, men are at higher risk than women at any given age
  • Many people do not get polyps until after the age of 50. 
  • People with a higher risk of getting colorectal cancer often get polyps before the age of 50. 
  • To lower the chance of colorectal cancer, it is vital to get screened at the right time.
    • If you are at average risk, start screening at age 50.
    • If you think you might be at high risk for colorectal cancer, talk to your doctor early, before age 50, to make a screening plan that’s right for you.


Colon Cancer Screening Can Save Your Life


  • With routine colorectal cancer screening, more than one-third of colorectal cancer deaths can be avoided.
  • Many tests can help find precancerous and cancerous growths. Finding them early could save your life.
  • Colorectal cancer screening is safe and effective.
  • Finding and getting rid of colon polyps prevents colon cancer, no matter what your risk is.
  • With simple steps, you can lower your risk of getting the disease. Talk to a gastroenterologist.


Check out AGA’s informative videos on colorectal cancer screening. Learn about why it’s important to get screened, screening options and tips to ensure a high-quality colonoscopy.



© AGA, September 2017

©AGA, July 2016

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