The procedure for testing for tumor markers is first a blood draw or urine specimen is sent to the lab for testing. The specimen is then combined with man-made antibodies that react with the tumor marker protein.
Rarely is a tumor marker is used to diagnose if a cancer is present. The oncologist uses a battery of testing in the diagnosis of cancer such as pet scan, MRI, biopsies,etc. Tumor markers are helpful in knowing the progression of the cancer during treatment.
Oncologist usually order the following tumor markers.
CEA Carcinoembryonic antigen is a protein associated with certain tumors and fetus. It is a glycoprotein and associated with the plasma membrane of a tumor membrane. It is from the plasma membrane that the carcinoembryonic antigen is released. At first it was used to identify colon caner but was later found in other cancers such as pancreatic,lung,gastric and breast. CEA was also found in non-cancer illnesses such as cirrhosis,
bowel inflammatory disease, chronic lung disease and pancreatitis. In advanced stage of cancer the CEA is elevated which means that the cancer survival of the patient is shortened.
AFP- Alpha- fetoprotein SELL has determined that this is the most single discriminating laboratory test indicative of a malignant disease. It is used in screening hepatatocellular disease.
AFP is elevated in testicular germ cell tumors containing embryonal or endodermal sinus elements. A defenitive positive marker value is highly sensitive in indicating relapse or response to treatment.
HCG - In pregnancy the HCG is produced by the syncytiotrophoblastic cells of the placenta and of course is elevated in pregnancy. It is a highly sensitive test in the detecting the smallest of trophoblastic neoplasms in women. The larger the tumor then the higher the HCG result. The HCG is essential for the oncologist measuring the effectiveness of the treatment.
Neuron Specific Enolase - Neuron indicates that this is part of the brain. When "ase" is seen at the end of the scientific word it is an enzyme. NSE is an isozyme of the glycolytic pathway that is strictly seen in the brain and the neuroendocrine tissue. This tumor marker is valuable in diagnosing and evaluating the treatment of tumors of the central nervous system, neuroblastomas, and APUD tumors. NSE is a immunohistochemical marker for tumors.
CA125 is a helpful tool in ovarian cancer because it is found in about 80% of non mucinous ovarian carcinomas. It is elevated on ovarian cancer. CA125 is used to let the oncologist know if the treatment for the cancer is working. CA125 is elevated in other cancers such as pancreas, endometrial,lung, breast and colon.
CA19-9 is an monoclonal antibody generated against colon carcinoma cell line to detect monosialoganglioside found in tissues of persons with gastrointestinal adenocarcinoma. It is also elevated in gastric, pancreatic, and colon cancer.
CA 15.3 helps to monitor certain cancers but most prominently breast cancer. This antigen sheds sheds into the blood because it is found on the surface of many types of cancer. It has been found that CA 15.3 in conjunction with Alkaline Phosphatase is elevated is found to be associated with increase chance of early recurrence of breast cancer. This marker is used to monitor treatment of breast cancer.
PSA means prostrate specific antigen. Another name is gamma-seminoprotein or Kallikrein. It is a glycoprotein and in humans it is encoded with KLK3 gene. It is secreted by the epithelial cells for the prostrate gland. Normal levels of PSA is produced in all men, but is elevated in prostrate cancer and other prostrate problems. PSA serum levels are drawn regularly from patients who are being treated to help the oncolgist know the progression of the cancer.
CA125 is a helpful tool in ovarian cancer because it is found in about 80% of non mucinous ovarian carcinomas. It is elevated on ovarian cancer. CA125 is used to let the oncologist know if the treatment for the cancer is working. CA125 is elevated in other cancers such as pancreas, endometrial,lung, breast and colon.
CA19-9 is an monoclonal antibody generated against colon carcinoma cell line to detect monosialoganglioside found in tissues of persons with gastrointestinal adenocarcinoma. It is also elevated in gastric, pancreatic, and colon cancer.
CA 15.3 helps to monitor certain cancers but most prominently breast cancer. This antigen sheds sheds into the blood because it is found on the surface of many types of cancer. It has been found that CA 15.3 in conjunction with Alkaline Phosphatase is elevated is found to be associated with increase chance of early recurrence of breast cancer. This marker is used to monitor treatment of breast cancer.
PSA means prostrate specific antigen. Another name is gamma-seminoprotein or Kallikrein. It is a glycoprotein and in humans it is encoded with KLK3 gene. It is secreted by the epithelial cells for the prostrate gland. Normal levels of PSA is produced in all men, but is elevated in prostrate cancer and other prostrate problems. PSA serum levels are drawn regularly from patients who are being treated to help the oncolgist know the progression of the cancer.
For more information go to tc-cancer.com , wilkipedia, National Cancer Institute
