One of these tests is the cancer antigen 27.29 (CA 27.29) blood test.
This is used to check for an antigen associated withbreast cancer.
An antigen is a protein on the surface of a cell that serves as an identifier.
Theresa Chiechi / Verywell
And CA 27.29 is one of several antigens that healthcare providers use as tumor markers for breast cancer.
A higher antigen level corresponds to recurrence, and a lower antigen level corresponds to treatment response.
Found in blood, urine, and tissue samples, these markers are signals of specific disease processes.
This can help healthcare providers distinguish between the types and/or stages of cancer.
This is because treatment can cause the tumor to release CA 27.29 antigens into the bloodstream.
Only abreast biopsycan diagnose breast cancer.
Routinemammographyis the preferred method of breast cancer screening, whether for new or recurring disease.
As such, the risks of the test are relatively small.
Injection site pain, bruising, or bleeding are possible, as is light-headedness or fainting.
Infection is rare, but can occur.
Before the Test
It is rare that the CA 27.29 is ordered on its own.
Youroncologistwill more than likely order a battery of tests to monitor your cancer or its response to therapy.
This may include a complete blood count (CBC),liver functions tests, andkidney function tests.
No preparation is needed for any of these tests.
Timing
The blood draw only takes a few minutes to perform.
Depending on registration and waiting time, expect to spend between 30 to 90 minutes at the testing site.
You may also be referred to a nearby lab.
Some people prefer wearing long sleeves so that they can cover the bandage or puncture mark after the test.
Food and Drink
There are no food or drink restrictions for the CA 27.29 test.
Your health insurance will usually cover some or all the cost if you have metastatic breast cancer.
This may not be true if the test is used for screening purposes.
Speak with your insurance company to confirm what yourco-pay or coinsurancecosts will be in advance of the test.
A consent form may be provided.
A phlebotomist will perform the blood draw.
Pre-Test
You will be led to a room and seated in a chair.
The phlebotomist will ask which arm you prefer the blood drawn from.
Throughout the Test
You will feel a tiny prick as the needle is inserted into your vein.
The vacuum-sealed tube will usually have a gold or red rubber cap.
The phlebotomist will then put an adhesive bandage over the wound.
After that, you’re free to continue with your day without limitations.
Redness or bruising may also occur.
Once the bleeding is fully stopped, you could remove the adhesive bandage.
Although infection is rare, it can sometimes occur.
Interpreting Results
The results of your blood test should be available within three to five working days.
The reference range is based on the expected values in a population of people.
An increase of more than 25% between tests is also considered clinically significant.
Taken together with other tools and clinical monitoring, this is a helpful test to have.
It is mostly noninvasive with minimal pain and adds to the larger clinical picture.
While it is not helpful for diagnosis or staging, it can be used in other ways.
Even if a value is high, you should not assume that cancer is the cause.
The CA 27.29 is only useful when used in combination with other tests.
Frequently Asked Questions
A cancer antigen number is also called a tumor marker.
It is a number that indicates the amount of cancer antigen in the body.
A cancer antigen is a protein made by cancer cells.
Different types of cancer can make different types of antigens.
A high CA 27.29 marker can mean a variety of things.
There is no clear link between stress and cancer or rising tumor markers.
Yes, they canand this is normal.
Stanford Health Care.CA 27-29 tumor marker.
2007;3(6):336-339. doi:10.1200/JOP.0768504
LabCorp.Cancer Antigen (CA) 27.29.
National Cancer Institute at the National Institutes of Health.Study suggests a link between stress and cancer coming back.
