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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 few of the most common.
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.
Other Works Consulted
Fischbach F, Dunning MB III (2015). A Manual of Laboratory and Diagnostic Tests, 9th ed. Philadelphia: Wolters Kluwer Health.
Pagana KD, Pagana TJ (2014). Mosby's Manual of Diagnostic and Laboratory Tests, 5th ed. St. Louis: Mosby.
Current as ofMarch 27, 2018
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineKathleen Romito MD - Family MedicineJimmy Ruiz MD - Hematology, Oncology
Current as of:
March 27, 2018
Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Jimmy Ruiz MD - Hematology, Oncology
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