Colorectal cancer (CRC) is the second leading cause of death from cancer in the US, with 155,800 new cases and 52,000 deaths projected for 2007. In the late 1990s, evidence emerging from clinical studies prompted several groups to issue or revise recommendations for CRC screening. There are over 130,000 cases of colorectal cancer diagnosed in the United States each year, and over 50,000 deaths. Colorectal cancer is the second leading cause of cancer deaths.

Like other cancers, it occurs when abnormal cells begin to grow and divide uncontrollably and form a mass, called a malignant tumor, in tissues or organs. Cancerous cells from these masses can enter the bloodstream or lymphatic system and spread to other organs or tissues. The sample removed from the biopsy is analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease). A biopsy may be performed during a colonoscopy, or it may be done on any tissue that is removed during surgery. Biologically, keloids are fibrotic tumors characterized by a collection of atypical fibroblasts with excessive deposition of extracellular matrix components (soft tissue components), especially collagen, fibronectin, elastin and proteoglycans. Generally, keloids contain relatively acellular (no cells) centers and thick, abundant collagen bundles that form nodules in the deep dermal portion of the lesion.

The disease occurs when cancerous cells first form in the tissues of the colon. It usually has no early signs. Adenomatous is a description of the type of cell involved in the cancer. Polyps are visible as outgrowths of the surface (mucosa) of the bowel. The test for FAP syndrome involves examining DNA in blood cells called lymphocytes (white blood cells), looking for mutations in the APC gene. No treatment to reduce cancer risk is currently available for people with FAP.

Cancerous tumors found in the colon or rectum also may spread to other parts of the body. The study showed that those patients whose tumors had the chromosomal instability type benefited significantly from chemotherapy. These chemotherapy-treated patients had a five-year survival of 74 percent compared to 66 percent in untreated patients. After removing the tumor and nearby tissue, the surgeon reconnects the healthy portions of the colon or rectum. If the healthy portions of the colon or rectum cannot be reconnected, a temporary or permanent opening (stoma) is made through the wall of the abdomen into the colon to provide a new path for waste material to leave the body.

If benign polyps are not removed from the large intestine, they can become malignant (cancerous ) over time . Food passes from the stomach into the small intestine and from there, to the colon (or large intestine) and rectum. The small intestine absorbs nutrients while the colon mainly absorbs the water in food, as well as some vitamins. The American Society for Gastrointestinal Endoscopy (ASGE), founded in 1941, is the preeminent professional organization dedicated to advancing the practice of endoscopy. ASGE promotes the highest standards of endoscopic training and practice, fosters endoscopic research, recognizes distinguished contributions to endoscopy, and is the foremost resource for endoscopic education.