First Time User? Enroll now.
COVID-19: Vaccine information, visitor restrictions, testing, treatment, and additional resources
Home > Health Library > Tumor Markers
A tumor marker is a substance released by cancer cells or by normal cells when cancer is in the body. Tumor markers can be hormones, proteins, enzymes, or other substances. Some conditions that are benign (not cancer) also release tumor markers.
Blood tests are the most common way to test for them. But some markers can be found in other body fluids and in tissue.
Tumor markers can show different things about cancer. Tests for tumor markers can be used (along with other tests) to help diagnose cancer. Tumor markers also can be used to see how far cancer has spread (what stage it is). Doctors can use them to see how well treatment is working and if cancer has come back (recurred) after treatment.
Some tumor markers help doctors choose the most effective treatment. They also can be used to predict when to start treatment again.
Low or no levels of tumor markers usually mean that treatment is working or that cancer hasn't come back.
There are many kinds of tumor markers. Here are a few of the most common.
CA stands for cancer antigen. This marker may be found in ovarian cancer. It is used mainly to see if cancer treatment is working or to see if cancer has come back.
Tumor tissue may be checked for these markers to see if hormone therapy or targeted therapies should be part of the treatment plan.
This marker may increase in prostate cancer. It decreases after successful treatment. It also may be used as a screening test for prostate cancer.
Tests that look for tumor markers, such as the 21-gene signature test (Oncotype DX) or the 70-gene signature test (Mammaprint), may be done on tumor tissue. Tumor markers can show if the cancer is likely to come back.
Current as of:
September 8, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineKathleen Romito MD - Family MedicineJimmy Ruiz MD - Hematology, Oncology
Current as of: September 8, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Jimmy Ruiz MD - Hematology, Oncology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2022 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.