CEA

Carcinoembryonic Antigen (CEA)

Carcinoembryonic antigen (CEA) is normally found in small amounts in the blood of most healthy people, but may become elevated in people who have cancer or some benign conditions. The primary use of CEA is in monitoring colorectal cancer, especially when the disease has spread (metastasized). CEA is also used after treatment to check for recurrence of colorectal cancer. However, a wide variety of other cancers can produce elevated levels of this tumor marker, including melanoma; lymphoma; and cancers of the breast, lung, pancreas, stomach, cervix, bladder, kidney, thyroid, liver, and ovary.
Elevated CEA levels can also occur in patients with noncancerous conditions, including inflammatory bowel disease, pancreatitis, and liver disease. Tobacco use can also contribute to higher-than-normal levels of CEA.

http://www.doctorslounge.com/oncology/labs/cea.htm
http://www.onemedplace.com/blog/archives/609