What is Colon Cancer?

The digestive system stores waste material in the colon. The rectum and the anus form a long, muscular tube called the large intestine. Tumors of the colon and rectum form on the inner wall of the large intestine. Benign polyps do not invade nearby tissue or spread to other parts of the body and can be easily removed during a colonoscopy. However, if they are not removed from the large intestine, they can become malignant over time.

Most of the cancers of the large intestine are believed to have developed from polyps. Cancer of the colon and rectum (also referred to as colorectal cancer) can invade and damage adjacent tissues and organs. Cancer cells can also break away or metastasize and spread to other parts of the body (such as liver and lung) where new tumors form. Once metastasis has occurred in colorectal cancer, a complete cure of the cancer is unlikely.

The Colon