What are tumor markers in the blood?
A tumor marker is a biomarker found in blood, urine, or body tissues that can be elevated by the presence of one or more types of cancer. There are many different tumor markers, each indicative of a particular disease process, and they are used in oncology to help detect the presence of cancer.
A tumor marker is a substance that is produced by the body in response to cancer, or is produced by the cancer itself. Some of these markers are specific to one cancer, while others are seen in several types of cancer. These markers are generally used to evaluate the patient’s response to treatment or to monitor for recurrence (return of the cancer after treatment). There are non-cancerous conditions that can cause markers to be elevated, so these must also be considered when interpreting the test results. Tumor markers can be used in conjunction with other tests (scans, biopsies, etc.) to help diagnose a patient who has symptoms suspicious for cancer. Some markers can help physicians to determine prognosis and treatment
Ideally, markers could be used as a screening tool for the general public. The goal of a screening test is to diagnose cancer early, when it is the most treatable and before it has had a chance to grow and spread. So far, the only tumor marker to gain some acceptance as a screening tool is the Prostate Specific Antigen (PSA) for prostate cancer, though this has its share of controversy Other markers are either not specific enough (too many false positives – a positive result, when no cancer is actually present – leading to expensive, anxiety producing and unnecessary follow-up testing), or they are not elevated early enough in the life of the cancer, and therefore the cancer cannot be detected any earlier than when symptoms begin to appear. Keep in mind that some substances used as markers are produced naturally in the body, and a “normal” level is not always zero.
The most common tumor markers that can easily be added to a full health check up test and are easily tested by blood analysis form the basis of the following three.
1.Prostate-specific antigen, or PSA, is a protein produced by cells of the prostate gland. The PSA test measures the level of PSA in a man’s blood. For this test, a blood sample is sent to a laboratory for analysis. The results are usually reported as nanograms of PSA per milliliter (ng/mL) of blood.
2. The carcinoembryonic antigen (CEA) test measures the amount of this protein that may appear in the blood of some people who have certain kinds of cancers, especially cancer of the large intestine (colon and rectal cancer). It may also be present in people with cancer of the pancreas, breast, ovary, or lung.
3. An alpha-fetoprotein (AFP) blood test checks the level of AFP in a pregnant woman’s blood. AFP is a substance made in the liver of an unborn baby (fetus). The amount of AFP in the blood of a pregnant woman can help see whether the baby may have such problems as spina bifida and anencephaly.
Different tumor markers may be used for different cancers. Also, many cancers do not have blood tumor markers that are useful for guiding care. In addition, how and when they are used varies quite a lot. For specific details about whether tumor markers may be a part of your diagnosis and treatment planning, talk with your doctor. You can also find detailed information about tumor markers in each cancer-specific section on Cancer.Net.
If you are interested in a full health check and would like to include any of the tests above then please contact Phyathai Sriracha Hospital Health Check up Center. The check up center is open seven days a week from 8:00 am and can be contacted by Email:[email protected] Tel: 089 – 7500293 www.phyathai-sriracha.com