When cancerous cells originate in the tissues of the colon, this is known as colon cancer. There are usually no early signs of the disease. When symptoms do appear, they can include bowel problems such as blood in the stool, narrow stools, and diarrhea or constipation. Some tests used to diagnose colon cancer include rectal exams, fecal occult blood tests (FOBT), and colonoscopies. Treatment options include surgery, chemotherapy, radiation therapy, or a combination of treatments.
Colon cancer is a disease in which malignant (cancer) cells first form in the tissues of the colon.
The colon is part of the digestive system, which consists of the esophagus, stomach, small intestine, and colon (large intestine). The digestive system's main job is to pass waste out of the body while removing and processing nutrients from the foods you eat. These nutrients include:
The first six feet of the large intestine are called the large bowel or colon. The last six inches are the rectum and the anal canal. The anal canal ends at the anus (the opening of the large intestine to the outside of the body).
The colon removes water from your stool and helps pass waste material out of the body.
People 50 years old or older have an increased risk of developing colon cancer. Other risk factors include having:
- A family history of colon or rectal cancer
- A personal history of the following cancers:
- A history of colon polyps
- A history of ulcerative colitis (ulcers in the lining of the large intestine) or Crohn's disease
- Certain hereditary conditions, such as familial adenomatous polyposis and hereditary nonpolyposis colon cancer (also known as HNPCC or Lynch Syndrome).
(Click Risk Factors for Colon Cancer for more information.)