Colorectal cancer is a disease in which cancer cells grow in either the colon or the rectum. The colon and rectum are parts of the body’s digestive system. They remove nutrients from food and store waste until it passes out of the body. The colon and primarily the rectum also absorb water from ingested materials. Normally, the cells in the colon and rectum divide in a regulated manner. If cells keep dividing when new cells are not needed, a mass of tissue called a tumor forms. A tumor can be benign or malignant.

Colon Cancer

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A benign tumor is not cancer. It does not spread to other parts of the body. Colon polyps are most often (but not always) benign tumors. By contrast, a malignant tumor is cancer. Cancer cells divide and damage tissue around them. They can enter the bloodstream and spread to other parts of the body. Some colon polyps develop cancer in them. Some colon cancers appear to arise from the lining of the colon without a polyp. Benign colon tumors are usually colon polyps.

Colon cancer is the second leading cause of cancer-related death in men and women in the United States. An estimated 50,000 deaths occurred in 2008. Approximately 148,000 people will be diagnosed with colon or rectal cancer this year; 108,000 will have colon cancer and 41,000 people will develop rectal cancer. Colorectal cancer is one of the most treatable forms of cancer, and the rate of successful treatment is high, especially when the cancer is treated early.

What are the risk factors for colorectal cancer?
What are the symptoms of colorectal cancer?
How is colorectal cancer diagnosed?
What are the treatments for colorectal cancer?
Are there screening tests for colorectal cancer?
How can I reduce my risk of colorectal cancer?
What questions should I ask my doctor?
What is it like to live with colorectal cancer?
Where can I get more information about colorectal cancer?