Phoenix, Arizona - Colon cancer is cancer of the large intestine (colon), which is the final part of your digestive tract. Most cases of colon cancer begin as small, noncancerous (benign) clumps of cells called adenomatous polyps. Over time some of these polyps can become colon cancers.

Polyps may be small and produce few, if any, symptoms. For this reason, doctors recommend regular screening tests to help prevent colon cancer by identifying and removing polyps before they turn into cancer.


Signs and symptoms of colon cancer include:

  • A change in your bowel habits, including diarrhea or constipation or a change in the consistency of your stool, that lasts longer than four weeks
  • Rectal bleeding or blood in your stool
  • Persistent abdominal discomfort, such as cramps, gas or pain
  • A feeling that your bowel doesn't empty completely
  • Weakness or fatigue
  • Unexplained weight loss

Many people with colon cancer experience no symptoms in the early stages of the disease. When symptoms appear, they'll likely vary, depending on the cancer's size and location in your large intestine.

When to see a doctor

If you notice any symptoms of colon cancer, such as blood in your stool or an ongoing change in bowel habits, do not hesitate to make an appointment with your doctor.

Talk to your doctor about when you should begin screening for colon cancer. Guidelines generally recommend that colon cancer screenings begin at age 50. Your doctor may recommend more frequent or earlier screening if you have other risk factors, such as a family history of the disease.