Colon cancer is the growth of cancer in the large intestine.
Cancer occurs when cells in the body divide without control or order. If cells keep dividing, a mass of tissue forms, called a growth or tumor. The term cancer refers to malignant tumors. They can invade nearby tissue and spread to other parts of the body.
Factors that may increase your risk of colon cancer include:
Colon cancer often does not have any symptoms. However, some symptoms associated with colon cancer include:
These may also be caused by other, less serious health conditions. Anyone experiencing these symptoms should see a doctor.
The doctor will ask about your symptoms and medical history. A physical exam will be done.
Tests to screen for cancer or precancerous polyps include:
Additional tests may be done to confirm the presence of cancer, determine what stage the cancer is in, and/or determine if the cancer has spread:
Treatment depends on the stage of the cancer but may include:
Surgery is the main treatment. It requires removal of the cancerous tumor and nearby colon tissue. Depending on the size and location of the tumor, the surgery may be done by:
In some cases, the tumor and nearby healthy colon tissue will be removed. Healthy tissue is removed in case the cancer has begun to spread. The removal of a part of the colon is called a hemicolectomy. In most cases, the remaining healthy portions of the colon are reconnected. Sometimes, the end of the healthy colon is temporarily or permanently attached to an opening in the abdomen. This is called a colostomy. It allows body waste to pass out of the body if the colon cannot do so.
Radiation therapy is the use of radiation to kill cancer cells and shrink tumors. It is directed at the site of the tumor from a source outside the body. This therapy is aimed at the immediate area of the cancer.
This therapy uses drugs to kill cancer cells. It may be given in many forms, including pill, injection, and catheter. The drugs enter the bloodstream and travel through the body killing mostly cancer cells. They can also kill some healthy cells. This therapy is systemic, meaning it affects your entire body.
If you are diagnosed with colon cancer, follow your doctor's instructions.
The causes of most cancers are not known. However, it is possible to prevent many colon and rectal cancers by finding and removing polyps that could become cancerous. Beginning at age 50, both men and women at average risk should follow one of five screening options:
Be sure to discuss these cancer screening tools with your doctor to see which option is best for you.
People with any of the following risk factors should begin colon and rectal cancer screening at age 40 or earlier and/or undergo screening more often:
There are also lifestyle changes that may reduce your risk of colon cancer, such as:
American Cancer Society
Public Health Agency of Canada
Colorectal Cancer Association of Canada
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Last reviewed September 2012 by Mohei Abouzied, MD
Last Updated: 2/8/2013