Tumor markers are substances found in the blood, urine or body tissues that can be elevated in cancer. There are many different tumor markers. They are used in oncology to help determine the presence of cancer. An elevated level of a tumor marker can indicate cancer, however there can often also be other causes of the elevation. Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... This article or section is in need of attention from an expert on the subject. ... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ... Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these cells to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ... Oncology is the medical subspecialty dealing with the study and treatment of cancer. ...

Tumor markers can be produced directly by the tumor or by non-tumor cells as a response to the presence of a tumor.

Tumor markers can be used in screening programs, such as screening for elevated levels of prostate specific antigen to indicate possible prostate cancer. Tumor markers are also used to monitor patients for cancer return. Prostate specific antigen (PSA, also known as kallikrein III, seminin, semenogelase, γ-seminoprotein and P-30 antigen) is a protein manufactured almost exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm to swim freely. ... Prostate cancer is a disease in which cancer develops in the prostate, a gland in the male reproductive system. ...

Tumor markers can be classified in two groups: Cancer-specific markers and tissue-specific markers.

Cancer-specific markers

Cancer-specific markers are related to the presence of cancerous tissue. Because there is a large overlap between the many different tumor types and the markers produced these markers tend to be unhelpful in making a diagnosis. They can, however, be useful in follow up of treated patients to describe progress of the disease before any further masses can be found clinically or by imaging. A few examples of these markers are CEA, CA19-9, CA125. Carcinoembryonic antigen (CEA) is a glycoprotein involved in cell adhesion. ... CA-125, also known as CA125, is an abbreviation for cancer antigen 125. ...

An example of a cancer-specific marker, CEA, or carcinoembryonic antigen, is a blood-borne protein, first noted to be produced by tumors of the gastrointestinal system. Further investigation showed that it was produced by the occasional lung and breast cancer case, meaning that an elevated level does not mean a bowel cancer. However, in a patient with a history of a treated bowel cancer, a rising CEA level is an early sign of bowel cancer return. This usually occurs before the site of return can be identified on imaging or examination, and so many oncologists question the wisdom of doing a blood test for CEA when the end result is bad news that terrifies the patient, but does not have much impact on treatment. An antigen is a substance that stimulates an immune response, especially the production of antibodies. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and...

Tissue-specific markers

Tissue-specific markers are related to specific tissues which have developed cancer. Generally speaking, these substances are not specifically related to the tumor, and may be present at elevated levels when no cancer is present. But unlike the previous group, elevated levels point to a specific tissue being at fault. Examples include PSA, beta-HCG - (Human chorionic gonadotropin), AFP - (Alpha-fetoprotein), AFP-L3 - (a lectin-reactive AFP) and Thyroglobulin. For example, if man has an elevated PSA, a search for prostate cancer will be undertaken. If an individual has an elevated level of beta-HCG, AFP or AFP-L3%, a search for a testicular or liver cancer, respectively, will be made. Prostate specific antigen (PSA, also known as kallikrein III, seminin, semenogelase, γ-seminoprotein and P-30 antigen) is a protein manufactured almost exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm to swim freely. ... The title given to this article is incorrect due to technical limitations. ... Human chorionic gonadotropin (hCG) is a peptide hormone produced in pregnancy, that is made by the embryo soon after conception and later by the syncytiotrophoblast (part of the placenta). ... Alpha-fetoprotein (AFP) is a protein that is normally only produced in the foetus during its development. ... In oncology, AFP-L3 is an isoform of Alpha-fetoprotein (AFP), a substance typically used in the triple test during pregnancy and for screening chronic liver disease patients for hepatocellular carcinoma (HCC). ... Thyroglobulin is a protein secreted by the thyroid gland. ... In oncology, AFP-L3 is an isoform of Alpha-fetoprotein (AFP), a substance typically used in the triple test during pregnancy and for screening chronic liver disease patients for hepatocellular carcinoma (HCC). ...

An example of a tissue-specific marker is PSA, or Prostate specific antigen, which is produced by the normal prostate. It is a protein enzyme called a serine protease that usually acts as an anticoagulant to keep semen liquid. Only small amounts leak into the circulation in normal circumstances. Enlarged prostates leak more substantial amounts, and cancerous prostates also leak substantial amounts. An accurate way to tell if an elevated PSA level results from cancer is to biopsy the prostate. Prostate specific antigen (PSA, also known as kallikrein III, seminin, semenogelase, γ-seminoprotein and P-30 antigen) is a protein manufactured almost exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm to swim freely. ... The prostate is an exocrine gland of the male mammalian reproductive system. ...