Colon Cancer Risk Factors and Symptoms

Risk Factors

Certain factors may increase the chance of developing colon cancer, though these factors do not directly cause cancer. Some people with multiple risk factors never develop colon cancer while others who do not have any risk factors do develop colon cancer. Although some risk factors cannot be changed, such as a person’s age or family history, there are some things you can do to help lower your risk, such as leading a more active lifestyle.

The average person has approximately a four percent chance of developing colon cancer. About five percent of colon cancers are inherited through a genetic variant that increases the risk for cancer while the remaining 95 percent are not inherited.

Early detection is important, so be sure to talk with your doctor about your risk factors. They include:

Learn more about risk factors.


Patients with early-stage colon cancer might not show symptoms. Most symptoms develop when the cancer has advanced or spread to other organs. Symptoms may include:

  • Change in bowel habits
  • Blood in stool
  • Diarrhea, constipation or feeling that the bowel does not fully empty
  • Stools that are narrower than usual
  • Frequent gas pains, bloating, fullness or cramps
  • Unexplained weight loss
  • Tiredness
  • Vomiting
  • Anemia (low red blood cell count)

Speak with your doctor if you are experiencing any new, unexplained or changing symptoms. These symptoms can have other causes, many of which are non-cancerous. Although having symptoms does not mean you have colon cancer, it is important to discuss any health concerns with your doctor who can help address your concerns and check for those other possible conditions as well as for colon cancer.

Learn more about the symptoms of colon cancer.

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