CA 19-9 is a protein shed by tumor cells into the bloodstream. This test measures CA 19-9 levels and is primarily used to monitor treatment of pancreatic cancer.
Category: Tumor Markers
Also known as: ca 19-9, ca19-9, ca 19 9, cancer antigen 19-9
Reference range: 0–37 U/mL (Source: ABIM)
Standard unit: U/mL
High values may indicate
High CA 19-9 levels may indicate pancreatic cancer, bile duct cancer, gallbladder cancer, or non-cancerous conditions such as pancreatitis, bile duct obstruction, or liver disease.
Low values may indicate
Low CA 19-9 levels are normal and may indicate a good response to cancer treatment in patients being monitored.