NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,916 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- CA 19-9 assay
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- A laboratory test that measures the level of CA 19-9 in the blood. CA 19-9 is a substance released into the blood by both cancer cells and normal cells. Higher than normal amounts of CA 19-9 in the blood can be a sign of pancreatic or other types of cancer or other conditions. The amount of CA 19-9 in the blood can be used to help keep track of how well cancer treatments are working or if cancer has come back. CA 19-9 is a type of tumor marker.