Article updated and reviewed by Kevin Knopf, MD, MPH; Director of Clinical Research, Annapolis Oncology Center and Associate Staff, Johns Hopkins Oncology Center on July 22, 2005.

Colorectal cancer is a disease in which cancerous growths (tumors) are found in the tissues of the colon and/or rectum. The colon and rectum are part of the digestive system. Together they form a long, muscular tube called the large intestine. The colon is the upper five to six feet of the large intestine; the rectum...