The CA 50 test measures the level of cancer antigen 50 in your blood. CA 50 is a tumour marker protein that is primarily associated with gastrointestinal cancers, including pancreatic, stomach and colorectal cancers.

Why it’s important:

• Cancer monitoring: CA 50 is most commonly used to help monitor patients with pancreatic cancer or stomach cancer, particularly to track the progression of the disease or response to treatment.
• Detect recurrence: For individuals with a history of gastrointestinal cancers, elevated CA 50 levels may indicate cancer recurrence or metastasis.
• Evaluate treatment effectiveness: The test can help assess whether treatment (e.g., chemotherapy, surgery) is working by monitoring changes in CA 50 levels.

Limitations of CA 50 testing:

• Non-specific marker: CA 50 is not specific to cancer and can be elevated in other non-cancerous conditions, which limits its ability to conclusively diagnose cancer.

False negatives: Not all patients with gastrointestinal cancers will have elevated CA 50 levels, particularly in early stages of the disease.