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Learning About Colon Cancer

Cancer in the colon

What is colon cancer?

Colon cancer happens when cells that are not normal grow in your colon. These cells grow together and form tumours.

Colon cancer occurs most often in people older than 50. As with other cancers, treatment works best when colon cancer is found early.

What happens when you have colon cancer?

Most cases begin as polyps, which are small growths inside the colon. These polyps are very common, and most of them do not turn into cancer.

Colon cancer usually grows very slowly. It usually takes years for the cancer to become large enough to cause symptoms. If the cancer is not removed and keeps growing, it eventually will invade and destroy nearby tissues and then spread farther, first to nearby lymph nodes. From there it may spread to other parts of the body.

What are the symptoms?

Colon cancer in its early stages usually doesn't cause any symptoms. Symptoms occur later, when the cancer may be harder to treat. The most common symptoms include:

  • Pain in the belly.
  • Blood in your stool or very dark stools.
  • A change in your bowel habits, such as more frequent stools or a feeling that your bowels are not emptying completely.
  • Always feeling tired.

How can you prevent colon cancer?

Screening tests can find or prevent many cases of colon cancer. They look for a certain disease or condition before any symptoms appear.

Screening tests that may find colon cancer early include:

  • Stool tests, such as the fecal immunochemical test or the fecal occult blood test.
  • Sigmoidoscopy, which lets your doctor look at the inside of the lower part of your colon using a lighted tube.
  • Colonoscopy, which lets your doctor look at the inside of your entire colon using a thin, flexible tube.

Experts recommend colon cancer testing for everyone age 50 and older who has a normal risk for colon cancer. People with a higher risk, such as those with a strong family history of colon cancer, should be tested sooner. Talk to your doctor about when you should be tested.

Here are other things you can do to help prevent colon cancer:

  • Watch your weight. Being very overweight may increase your chance of getting colon cancer.
  • Eat well. Eat more whole grains, fruits, vegetables, poultry, and fish. And eat less red meat, refined grains, and sweets.
  • Limit drinking. Drink no more than 3 alcohol drinks a day if you're a man, and no more than 2 drinks a day if you're a woman.
  • Get active. Keep up a physically active lifestyle.
  • Quit smoking. If you smoke cigarettes, quit smoking to reduce your chance of getting colon cancer.

How is colon cancer treated?

  • Surgery is almost always used to treat colon cancer. The cancer is more easily removed when it is found early.
  • If the cancer has spread into the wall of the colon or farther, you may also need radiation or chemotherapy.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse call line if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

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