What is CEA?

• A. A hormone produced by pancreas
• B. Found in fetal tissue, absent after birth, detected in numerous cancers
• C. A protein expressed in adult liver only
• D. An enzyme involved in glycolysis

Answer: (B)

Carcinoembryonic antigen (CEA) is a glycoprotein that is produced in fetal tissues and is largely absent after birth. In many cancers, especially colorectal cancer, CEA is re-expressed and detectable at elevated levels in the blood. Clinically, it’s used to monitor treatment response and check for recurrence in cancers that express CEA, rather than as a general screening test because levels can also rise in noncancer conditions (smoking, inflammation, liver disease).

This description fits the statement that CEA is found in fetal tissue, becomes absent after birth, and is detected in numerous cancers. It isn’t a pancreatic hormone, a liver-specific enzyme, or a glycolytic enzyme, so the other options don’t match what CEA is.