Tumor Marker Tests Test
Tumor marker tests look for substances made by cancer cells or by normal cells in response to cancer. They are most often used after a cancer diagnosis to help stage cancer, choose treatment, monitor treatment, or check for cancer that remains or returns. Some tests may also be used for screening in people at high risk.
What this test measures
These tests look for tumor markers, which are substances that are made by cancer cells or by normal cells in response to cancer. For example, some cancer cells make certain proteins in larger amounts than normal cells do. These proteins can act as tumor markers because their presence may mean cancerous cells are present.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
A high level of tumor markers may mean cancerous cells are present, but it can also be caused by conditions that are not cancer. Tumor marker tests cannot tell whether the markers come from cancer or another condition.
Frequently asked questions
What are tumor markers?
Tumor markers are substances made by cancer cells or by normal cells in response to cancer. They can be found in body fluids like blood or urine, or in tumor tissue from a biopsy.
Are tumor marker tests used to diagnose cancer?
Tumor marker tests that use body fluids have a limited role in screening and cannot diagnose cancer. A biopsy is usually needed to diagnose or rule out cancer. Tests that use cells from a tumor may help diagnose cancer when used with other tests.
What can cause a high tumor marker level besides cancer?
Some conditions that are not cancer may also cause high levels of certain tumor markers. The test cannot tell whether the markers come from cancer or another condition.
How are tumor marker tests used after a cancer diagnosis?
They may help find out if cancer has spread, predict how fast it may grow, select the right treatment, monitor treatment, and find any cancer that remains or comes back after treatment.
What are some common tumor markers?
Common tumor markers include CA-125 (ovarian cancer), CA 15-3 and CA 27-29 (breast cancer), PSA (prostate cancer), CEA (colorectal and other cancers), AFP (liver cancer), and B2M (multiple myeloma, lymphomas, leukemias).
Related lab tests
Sources
- MedlinePlus: Tumor Marker Tests — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.