Carbohydrate Antigen 72-4 (CA 72-4)
Other marker
CA 72-4
Carbohydrate Antigen 72-4 (CA 72-4)
A tumour-associated glycoprotein antigen used mainly as a marker for gastric (stomach) cancer, and sometimes ovarian and other gastrointestinal cancers. It is chiefly used to monitor known disease rather than to screen.
PED Notes
Uncommon on athlete panels and with no PED-specific link. Its practical quirks: CA 72-4 can be transiently raised by benign gastrointestinal conditions and, notably, by some medications and supplements (proton pump inhibitors and colchicine have been reported to affect levels), so a mild isolated elevation is usually not meaningful. It is most often ordered alongside CEA and CA 19-9 for gastric cancer monitoring.
When high
When elevated (>6.9 U/mL):
- Benign gastrointestinal conditions (gastritis, peptic ulcer, pancreatitis, benign ovarian cysts) and certain drugs can cause modest elevations; interpret cautiously and repeat
- The marker is used to monitor a diagnosed gastric or ovarian cancer, often in combination with CEA and CA 19-9; it is not a screening test for healthy people
- Persistent or rising values without a benign explanation, particularly with upper-GI symptoms, warrant gastroenterology review and endoscopy/imaging
Action: A single mildly raised CA 72-4 in a well person is usually benign. Review medications, repeat the test, and escalate only for persistent elevation or symptoms.
History Chart
Reading History
Frequently Asked Questions
Reference Ranges
Standard Range