What is CA19-9 tumour marker and blood test?

A CA 19-9 blood test measures the amount of a protein called CA 19-9 (cancer antigen 19-9) in the blood. CA 19-9 is a type of biomarker/tumour marker. Tumour markers are substances made by cancer cells or by normal cells in response to cancer in the body. CA 19-9 is the most well-investigated and validated blood biomarker for the detection of symptomatic pancreatic cancer. CA 19-9 serum levels can help predict postoperative recurrence and provide critical information about prognosis, overall survival, and treatment response. (Sources: medlineplus.gov)

For your Ca19 9 blood test, your healthcare professional will use a small needle to take blood from a vein in your arm. You will feel a scratch while this is being done. The whole process shouldn’t take more than a few minutes.

If you are undergoing treatment for pancreatic cancer, you may have several Ca19 9 blood tests over a period of time. The results will show how your Ca19 9 levels are changing. For instance:

  • Increasing levels of Ca19 9 may indicate that your tumour is growing and/or treatment has not been successful.
  • Decreasing levels of Ca19 9 may indicate that your tumour is shrinking and/or treatment has been successful.
  • Levels that stay the same indicate that your cancer is stable.
  • If your levels decrease after treatment but later increase, this may indicate that your cancer has returned or grown.

Whatever your results, you will need to discuss your Ca19 9 blood test with your doctors and other healthcare providers. You may need additional tests to understand what’s going on. The PanKind website offers lots more information on pancreatic cancer for patients and their carers.

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