Colorectal Cancer
Colorectal cancer, also known as cancer of the colon or cancer of the rectum, is the fourth most common cancer in both men and women. The disease forms in the cells in the lining of the colon or the rectum.
About Colorectal Cancer
Abnormal cells in the lining of the rectum or colon may develop small growths called polyps. While most polyps are non-cancerous, these polyps can develop into colorectal cancer. Regular screening for polyps is recommended for people older than 50.
When colorectal cancer forms, it may metastasize through the walls of the colon or rectum to nearby organs and tissue. It may also invade nearby lymph nodes and travel to other parts of the body.
Who’s at risk?
More than 90 percent of people diagnosed with colorectal cancer are over the age of 50. The average diagnosis age is in the mid-60s.
Risk Factors
While the exact cause of colorectal cancer is unknown, the following factors have been found to increase your risk of the disease:
- Colorectal polyps: While not cancerous, polyps can develop into cancer if left untreated.
- Personal history: Close relatives with the disease.
- Family history: Previous diagnosis of colorectal cancer or cancers of the ovary, uterus or breast.
- Genetic alterations: Inherited conditions caused by changes to certain genes. The most common is hereditary nonpolyposis colon cancer (HNPCC). Another rare inherited condition is called familial adenomatous polyposis (FAP).
- Diet: Diets high in fat and low in calcium, folate and fiber.
- Cigarette smoking
Treatment
Treatment options for colorectal cancer include surgery, radiation therapy and chemotherapy. A combination of treatments may also be used.
The most common treatment is surgery. A colonoscope can be used to remove small cancerous polyps. Removal of part of the rectum or colon may be required for more advanced cancers. Learn more about gastrointestinal surgery.
Some information on this page is provided by the National Cancer Institute and the American Cancer Society.