CA 19-9 Tumour Marker Blood Test (Cancer Antigen 19-9)

The CA 19-9 blood test measures the level of Cancer Antigen 19-9 (CA 19-9), a tumour marker that may be elevated in certain cancers and some non-cancerous conditions. The CA 19-9 tumour marker blood test is not a diagnostic test or a general screening test for cancer. It is primarily used alongside other clinical investigations to monitor patients with a known condition, assess response to treatment, or check for changes over time. A raised CA 19-9 result does not necessarily mean that cancer is present. Levels may also be increased by a range of benign conditions, including inflammation, gallstones, bile duct obstruction, pancreatitis and liver disease. Results should always be interpreted by a doctor alongside your symptoms, medical history, imaging scans and any other relevant laboratory tests.