CEA is a glycoprotein normally produced during fetal development but usually absent or present at very low levels in healthy adults.

Elevated CEA levels may indicate malignancy or certain benign conditions.

Clinical uses include:

Monitoring colorectal cancer progression and recurrence.

Supporting diagnosis of cancers such as pancreatic, gastric, breast, and lung cancer.

Evaluating response to cancer treatment.

Occasionally elevated in non-cancerous conditions (smoking, liver disease, inflammatory bowel disease).

The test is performed using a blood sample.

Analyte: Carcinoembryonic Antigen (CEA) concentration in serum.

Normal Range: < 3 ng/mL (non-smokers); < 5 ng/mL (smokers) — varies by lab.

Abnormal Findings:

Elevated CEA: Suggests possible malignancy, recurrence, or metastasis.

Moderate elevation: May occur in benign conditions (smoking, liver disease, pancreatitis).

Clinical Use:

Provides a tumor marker for colorectal and other cancers.

Helps monitor treatment effectiveness and recurrence.

Not recommended as a screening test for cancer due to limited specificity.