Colon cancer is the second leading cause of cancer deaths, after lung cancer. Early detection is essential to maximizing the potential for recovery. When caught early, it's 90% curable.

A colonoscopy is a visual examination of the colon using a fiber optic endoscope. This is a flexible tube that is about the size of a finger. With the patient awake but sedated, this tool is inserted into the anus, and then advanced slowly, under visual control, into the rectum and through the colon. It is performed by either looking through the instrument or viewing a TV monitor. The bowel is examined for polyps, hemorrhagic sites, ulcerations, etc. Sometimes the physician performing the colonoscopy may do other minor procedures such as a tissue biopsy or removal of a polyp.

Colonoscopies are performed:

• to screen for colon cancer, especially when there is a strong family history of the disease,
• to diagnose/manage inflammatory bowel disease, Crohn's disease, irritable bowel syndrome, etc.,
• to evaluate an abnormality found by a barium enema,
• to remove colon polyps,
• to discover the reason for blood in the stools.

Patients are given detailed instructions before the colonoscopy. It is very important to follow the instructions carefully. The colon must be completely clean for a successful test.