2016-06-16 17:22:53 UTC

Colorectal Cancer (CRC) 102: Symptoms

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I feel fine. Why not wait for these symptoms to develop, rather than have a colonoscopy?

  • Colorectal cancers found in patients with symptoms are more advanced and less likely to be cured.
  • Colorectal cancers found in people without symptoms are not as advanced and more frequently cured.
  • Precancerous polyps usually cause no symptoms, and removal of these polyps prevents colon cancer.

Colorectal cancer mostly starts with no symptoms at all, which is why routine screening beginning at age 50 for all normal-risk individuals is so important. 

Over time, though, there are a number of warning signs that can happen, such as:

  • Rectal bleeding.
  • Blood in your stool (bright red, black or very dark).
  • Temporary change in your bowel movements, especially in the shape of the stool (e.g., thin like a pencil).
  • Pain in having a bowel movement or the urge to move your bowels without having a bowel movement.
  • Frequent cramping pain in your lower belly.
  • Frequent gas pains.
  • Weight loss without dieting.


What should I do if I have these symptoms? 


If you are having any of the above symptoms, especially if you are at risk of colorectal cancer, call your gastroenterologist or primary-care physician right away. He or she will ask questions about your symptoms and figure out the best diagnostic test for you. 



© AGA, September 2017

©AGA, July 2016

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