Carcinoembryonic antigen (CEA)

An acid glycoprotein in the periphery of tumor cell membrane which is released into surrounding body fluids.

An oncofetal antigen that is normally produced in the fetal GI tract and is present at low levels in healthy adults.

Levels are elevated in cancers which include colon, breast, lung, ovary and pancreas.

Levels may be elevated in benign conditions such as diverticulitis, pancreatitis and peptic ulcers.

Not proven to be useful in screening asymptomatic individuals because of its low sensitivity and specificity.

Usefulness largely confined to surveillance after colon and rectal cancer surgery to allow for early identification of recurrence.

Preoperative CEA levels above 5 ng/ml predict poor outcomes in patients who underwent curative resections for colon cancer.

Low postoperative CEA is also associated with better prognosis, regardless of preoperative levels.

Cochrane review meta-analysis of 23 studies found that poolrd sensitivity of CEA at detecting colon cancer recurrence was 71% and a pooled specificity was 88% when applying a threshold of 5 ng/mL.

Patients with non-small cell lung cancer (NSCLC) with elevated CEA more likely to be sensitive to gefitinib than patients with a normal CEA.

ASCO and the National Comprehensive Cancer Network recommend postoperative monitoring of CEA for colon cancer resection every 3-6 months for 5 to 6 years for patients with resected stage Ii and II colorectal cancers.

Colon cancer surveillance with CEA testing alone is not sufficient as 20-30% of patients do not have an elevation with cancer recurrence.

Leave a Reply

Your email address will not be published.