BCR-ABL1 Genetic Test
Reviewed
Also called: BCR-ABL, BCR-ABL fusion, Philadelphia chromosome, t(9;22), Quantitative BCR-ABL1
A BCR-ABL1 genetic test uses a sample of blood or bone marrow to look for an abnormal gene called BCR-ABL1.
Specimen: Blood or bone marrow
Why this test may be ordered
- To diagnose or rule out chronic myeloid leukemia (CML)
- To diagnose or rule out Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL)
- To help plan treatment for blood cancers that involve BCR-ABL1
- To see if cancer treatment is working
- To monitor for cancer recurrence after treatment
Preparation and collection
You usually don't need any special preparations for a blood test. If you're having a bone marrow test, your provider will tell you whether you need to fast (not eat or drink) for a few hours before the procedure.
A BCR-ABL1 genetic test usually uses a sample of blood or bone marrow. If you are having a blood test, a health care professional will take a blood sample from a vein in your arm, using a small needle. If you are having a bone marrow test, a provider usually takes a sample from the back of the hip bone.
There is very little risk to having a blood test. After a bone marrow test, you may feel stiff or sore where the sample was taken. This usually goes away in a few days. If you need pain relief, talk with your provider.
Understanding results
If you had BCR-ABL1 genetic testing to diagnose a blood cancer, your provider will probably use the results of more than one test to make a diagnosis.
- BCR-ABL1 gene detected (with abnormal white cells and Philadelphia chromosome): Your provider will likely diagnose either chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) if your tests show all three of these results: Abnormal white blood cells, The BCR-ABL1 gene, The Philadelphia chromosome. Limitation: In certain cases, a person may have CML without having the Philadelphia chromosome, but this isn't common. Next step: Ask your provider to explain what your test results mean for your health and treatment plan.
- Decreased BCR-ABL1 level (during treatment): If the amount of BCR-ABL1 in your sample decreases, it means your treatment is working to some degree. Limitation: The test method can affect your results. So, it's important to have your tests done the same way, and usually in the same lab. Next step: If you had a BCR-ABL1 gene test to see if your cancer treatment is working, your provider will compare your results with past test results to look for changes over time.
- Increased BCR-ABL1 level (during or after treatment): If the amount of BCR-ABL1 in your sample increases, it may mean your treatment is not working. An increase in BCR-ABL1 levels after successful treatment, may mean your cancer has come back. Limitation: The test method can affect your results. So, it's important to have your tests done the same way, and usually in the same lab. Next step: You may need to try another treatment or have more tests.
- Different laboratory methods may yield different results. It is important to have tests done consistently in the same lab for accurate monitoring.
- In certain cases, a person may have CML without having the Philadelphia chromosome, but this isn't common.
- This test is not diagnostic on its own; it must be interpreted alongside other laboratory and clinical findings.
What to do next
Ask your provider to explain what your test results mean for your health and treatment plan.
- What does my BCR-ABL1 test result mean?
- How often will I need this test?
- What is the difference between a blood test and a bone marrow test for this test?
- Can I pass the BCR-ABL1 gene change to my children?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.