A tumor marker is a substance found in the blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

, urine

Urine

Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...

, or body tissues

Biological tissue

Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...

 that can be elevated in cancer

Cancer

Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

, among other tissue types. There are many different tumor markers, each indicative of a particular disease process, and they are used in oncology

Oncology

Oncology is a branch of medicine that deals with cancer...

 to help detect the presence of cancer. An elevated level of a tumor marker can indicate cancer; however, there can also be other causes of the elevation.

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

Tumor antigen

Tumor antigen is an antigenic substance produced in tumor cells, i.e., it triggers an immune response in the host. Tumor antigens are useful in identifying tumor cells and are potential candidates for use in cancer therapy.- Mechanism of tumor antigenesis:...

s, but not all tumor antigens can be used as tumor markers.

Uses

Uses of tumor markers can broadly be classified as follows:

• Screening for common cancer
  Cancer
  Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
  
  s on a population basis. Example: elevated prostate specific antigen
  Prostate specific antigen
  Prostate-specific antigen also known as gamma-seminoprotein or kallikrein-3 is a glycoprotein that in humans is encoded by the KLK3 gene. KLK3 is a member of the kallikrein-related peptidase family that are secreted by the epithelial cells of the prostate gland...
  
   suggests prostate cancer
  Prostate cancer
  Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, there are cases of aggressive prostate cancers. The cancer cells may metastasize from the prostate to other parts of the body, particularly...
  
  .
• Monitoring of cancer
  Cancer
  Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
  
   survivors after treatment. Example: elevated AFP
  Alpha-fetoprotein
  Alpha-fetoprotein is a protein that in humans is encoded by the AFP gene....
  
   in a child previously treated for teratoma
  Teratoma
  A teratoma is an encapsulated tumor with tissue or organ components resembling normal derivatives of all three germ layers. There are rare occasions when not all three germ layers are identifiable...
  
   suggests relapse
  Relapse
  Relapse, in relation to drug misuse, is resuming the use of a drug or a dependent substance after one or more periods of abstinence. The term is a landmark feature of both substance dependence and substance abuse, which are learned behaviors, and is maintained by neuronal adaptations that mediate...
  
   with endodermal sinus tumor
  Endodermal sinus tumor
  Endodermal sinus tumor , also known as yolk sac tumor , is a member of the germ cell tumor group of cancers. It is the most common testicular tumor in children under 3, and is also known as infantile embryonal carcinoma. This age group has a very good prognosis...
  
  .
• Diagnosis of specific tumor types, particularly in certain brain tumor
  Brain tumor
  A brain tumor is an intracranial solid neoplasm, a tumor within the brain or the central spinal canal.Brain tumors include all tumors inside the cranium or in the central spinal canal...
  
  s and other instances where biopsy
  Biopsy
  A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
  
   is not feasible.

As stated in the BMJ 2009, tumour markers should not generally be used for the purpose of diagnosis of cancers, as opposed to monitoring purposes in certain cancers, or in certain cases, screening purposes. The use of these tests without understanding their utility has resulted in inappropriate use of tumour marker blood tests, which has also resulted in further inappropriate over-investigation for cancers.

Techniques

Tumor markers can be detected by immunohistochemistry

Immunohistochemistry

Immunohistochemistry or IHC refers to the process of detecting antigens in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues. IHC takes its name from the roots "immuno," in reference to antibodies used in the procedure, and...

.

If repeated measurements of tumor marker are needed, some clinical testing laboratories provide a special reporting mechanism, a serial monitor, that links test results and other data pertaining to the person being tested. This requires a unique identifier for the person. In the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 commonly a Social Security number

Social Security number

In the United States, a Social Security number is a nine-digit number issued to U.S. citizens, permanent residents, and temporary residents under section 205 of the Social Security Act, codified as . The number is issued to an individual by the Social Security Administration, an independent...

 & Civil Personal Record (CPR) in Bahrain

Bahrain

' , officially the Kingdom of Bahrain , is a small island state near the western shores of the Persian Gulf. It is ruled by the Al Khalifa royal family. The population in 2010 stood at 1,214,705, including 235,108 non-nationals. Formerly an emirate, Bahrain was declared a kingdom in 2002.Bahrain is...

 are used for this. One important function of this mechanism is to ensure that each test is performed using the same assay kit. For example, for AFP

Alpha-fetoprotein

Alpha-fetoprotein is a protein that in humans is encoded by the AFP gene....

 many different commercial assay kits, based on different technologies, are available. AFP measurements obtained using different assay kits are not comparable unless special calculations are performed.

Interlaboratory proficiency testing for tumor marker tests, and for clinical tests more generally, is an emerging field.In the United States, New York state is prominent in advocating such research.

Examples

Tumor marker	Associated tumor types
Alpha fetoprotein (AFP)	germ cell tumor Germ cell tumor A germ cell tumor is a neoplasm derived from germ cells. Germ cell tumors can be cancerous or non-cancerous tumors. Germ cells normally occur inside the gonads... , hepatocellular carcinoma Hepatocellular carcinoma Hepatocellular carcinoma is the most common type of liver cancer. Most cases of HCC are secondary to either a viral hepatitide infection or cirrhosis .Compared to other cancers, HCC is quite a rare tumor in the United States...
CA15-3 Ca15-3 CA15-3 is a tumor marker used to monitor certain cancers, especially breast cancer. It is found on the surface of many types of cancer cells and shed into the blood stream...	breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
CA19-9 CA19-9 CA19-9 is a tumor marker that is used primarily in the management of pancreatic cancer.-History:...	Mainly pancreatic cancer Pancreatic cancer Pancreatic cancer refers to a malignant neoplasm of the pancreas. The most common type of pancreatic cancer, accounting for 95% of these tumors is adenocarcinoma, which arises within the exocrine component of the pancreas. A minority arises from the islet cells and is classified as a... , but also colorectal cancer Colorectal cancer Colorectal cancer, commonly known as bowel cancer, is a cancer caused by uncontrolled cell growth , in the colon, rectum, or vermiform appendix. Colorectal cancer is clinically distinct from anal cancer, which affects the anus....  and other types of gastrointestinal cancer Gastrointestinal cancer Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract, including the esophagus, stomach, biliary system, pancreas, bowels, and anus. The symptoms relate to the organ affected, and can include obstruction , abnormal bleeding, or other associated problems... .
CA-125 CA-125 CA-125 also known as mucin 16 or MUC16 is a protein that in humans is encoded by the MUC16 gene. MUC16 is a member of the mucin family glycoproteins...	Mainly ovarian cancer Ovarian cancer Ovarian cancer is a cancerous growth arising from the ovary. Symptoms are frequently very subtle early on and may include: bloating, pelvic pain, difficulty eating and frequent urination, and are easily confused with other illnesses.... , but may also be elevated in for example endometrial cancer Endometrial cancer Endometrial cancer refers to several types of malignancies that arise from the endometrium, or lining, of the uterus. Endometrial cancers are the most common gynecologic cancers in the United States, with over 35,000 women diagnosed each year. The incidence is on a slow rise secondary to the... , fallopian tube cancer Fallopian tube cancer Primary fallopian tube cancer , often just tubal cancer, is a malignant neoplasm that originates from the fallopian tube.-Frequency:... , lung cancer Lung cancer Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary... , breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...  and gastrointestinal cancer Gastrointestinal cancer Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract, including the esophagus, stomach, biliary system, pancreas, bowels, and anus. The symptoms relate to the organ affected, and can include obstruction , abnormal bleeding, or other associated problems... . May also increase in endometriosis Endometriosis Endometriosis is a gynecological medical condition in which cells from the lining of the uterus appear and flourish outside the uterine cavity, most commonly on the ovaries. The uterine cavity is lined by endometrial cells, which are under the influence of female hormones... .
Calretinin Calretinin Calretinin also known as 29 kDa calbindin is a vitamin D-dependent calcium-binding protein involved in calcium signaling. In humans, the calretinin protein is encoded by the CALB2 gene.- Function :...	mesothelioma Mesothelioma Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium... , sex cord-gonadal stromal tumour, adrenocortical carcinoma Adrenocortical carcinoma Adrenocortical carcinoma, also adrenal cortical carcinoma and adrenal cortex cancer, is an aggressive cancer originating in the cortex of the adrenal gland. Adrenocortical carcinoma is a rare tumor, with incidence of 1-2 per million population annually... , synovial sarcoma Synovial sarcoma A synovial sarcoma is a rare form of cancer which usually occurs near to the joints of the arm, neck or leg. It is one of the soft tissue sarcomas....
Carcinoembryonic antigen Carcinoembryonic antigen Carcinoembryonic antigen is a glycoprotein involved in cell adhesion. It is normally produced during fetal development, but the production of CEA stops before birth. Therefore, it is not usually present in the blood of healthy adults, although levels are raised in heavy smokers...	gastrointestinal cancer Gastrointestinal cancer Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract, including the esophagus, stomach, biliary system, pancreas, bowels, and anus. The symptoms relate to the organ affected, and can include obstruction , abnormal bleeding, or other associated problems... , cervix cancer, lung cancer Lung cancer Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary... , ovarian cancer Ovarian cancer Ovarian cancer is a cancerous growth arising from the ovary. Symptoms are frequently very subtle early on and may include: bloating, pelvic pain, difficulty eating and frequent urination, and are easily confused with other illnesses.... , breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas... , urinary tract cancer
CD34 CD34 CD34 molecule is a cluster of differentiation molecule present on certain cells within the human body. It is a cell surface glycoprotein and functions as a cell-cell adhesion factor. It may also mediate the attachment of stem cells to bone marrow extracellular matrix or directly to stromal cells...	hemangiopericytoma Hemangiopericytoma A hemangeopericytoma is a type of soft tissue sarcoma that originates in the pericytes in the walls of capillaries. When inside the nervous system, although not strictly a meningioma tumor, it is a meningeal tumor with an especially aggressive behavior.It was characterized in... /solitary fibrous tumor Solitary fibrous tumor Solitary fibrous tumor is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue. Approximately 78% to 88% of SFT's are benign and 12% to 22% are malignant.... , pleomorphic lipoma Pleomorphic lipoma Pleomorphic lipomas, like spindle-cell lipomas, occur for the most part on the backs and necks of elderly men, and are characterized by floret giant cells with overlapping nuclei.... , gastrointestinal stromal tumor Gastrointestinal stromal tumor A gastrointestinal stromal tumor is one of the most common mesenchymal tumors of the gastrointestinal tract... , dermatofibrosarcoma protuberans Dermatofibrosarcoma protuberans Dermatofibrosarcoma protuberans is a very rare tumor. It is a rare neoplasm of the dermis layer of the skin, and is classified as a sarcoma. There is only about 1 case per million per year. DFSP is a fibrosarcoma, more precisely a cutaneous soft tissue sarcoma...
CD99 CD99 CD99 antigen also known as MIC2 or single-chain type-1 glycoprotein is a protein that in humans is encoded by the CD99 gene. The protein has a mass of 32 kD...	Ewing sarcoma Ewing sarcoma Ewing sarcoma is a malignant round-cell tumour. It is a rare disease in which cancer cells are found in the bone or in soft tissue. The most common areas in which it occurs are the pelvis, the femur, the humerus, the ribs and clavicle.... , primitive neuroectodermal tumor Primitive neuroectodermal tumor Primitive neuroectodermal tumor is a neural crest tumor. It is a rare tumor, usually occurring in children and young adults under 25 years of age... , hemangiopericytoma Hemangiopericytoma A hemangeopericytoma is a type of soft tissue sarcoma that originates in the pericytes in the walls of capillaries. When inside the nervous system, although not strictly a meningioma tumor, it is a meningeal tumor with an especially aggressive behavior.It was characterized in... /solitary fibrous tumor Solitary fibrous tumor Solitary fibrous tumor is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue. Approximately 78% to 88% of SFT's are benign and 12% to 22% are malignant.... , synovial sarcoma Synovial sarcoma A synovial sarcoma is a rare form of cancer which usually occurs near to the joints of the arm, neck or leg. It is one of the soft tissue sarcomas.... , lymphoma Lymphoma Lymphoma is a cancer in the lymphatic cells of the immune system. Typically, lymphomas present as a solid tumor of lymphoid cells. Treatment might involve chemotherapy and in some cases radiotherapy and/or bone marrow transplantation, and can be curable depending on the histology, type, and stage... , leukemia Leukemia Leukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases... , sex cord-gonadal stromal tumour
CD117 CD117 Mast/stem cell growth factor receptor also known as proto-oncogene c-Kit or tyrosine-protein kinase Kit or CD117 is a protein that in humans is encoded by the KIT gene...	gastrointestinal stromal tumor Gastrointestinal stromal tumor A gastrointestinal stromal tumor is one of the most common mesenchymal tumors of the gastrointestinal tract... , mastocytosis Mastocytosis Mastocytosis is a group of rare disorders of both children and adults caused by the presence of too many mast cells and CD34+ mast cell precursors in a person's body.- Classification :Mastocytosis can occur in a variety of forms:... , seminoma
Chromogranin Chromogranin Granin is a protein family of regulated secretory proteins ubiquitously found in the cores of amine and peptide hormone and neurotransmitter dense-core secretory vesicles.- Function :...	neuroendocrine tumor
Cytokeratin Cytokeratin Cytokeratins are proteins of keratin-containing intermediate filaments found in the intracytoplasmic cytoskeleton of epithelial tissue. The term "cytokeratin" began to be used in the late 1970s when the protein subunits of keratin intermediate filaments inside cells were first being identified and...  (various types)	Many types of carcinoma Carcinoma Carcinoma is the medical term for the most common type of cancer occurring in humans. Put simply, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during... , some types of sarcoma Sarcoma A sarcoma is a cancer that arises from transformed cells in one of a number of tissues that develop from embryonic mesoderm. Thus, sarcomas include tumors of bone, cartilage, fat, muscle, vascular, and hematopoietic tissues...
Desmin Desmin Desmin is a protein that in humans is encoded by the DES gene.Desmin is a type III intermediate filament found near the Z line in sarcomeres. It was first described in 1976, first purified in 1977, the gene was cloned in 1989, and the first knock-out mouse was created in 1996. Desmin is only...	smooth muscle sarcoma, skeletal muscle sarcoma, endometrial stromal sarcoma Endometrial stromal sarcoma Endometrial stromal sarcoma is a rare endometrial tumor arising from the stroma of the endometrium rather than the glands. There are three grades for endometrial stromal tumors, as follows...
Epithelial membrane protein (EMA)	many types of carcinoma Carcinoma Carcinoma is the medical term for the most common type of cancer occurring in humans. Put simply, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during... , meningioma Meningioma The word meningioma was first used by Harvey Cushing in 1922 to describe a tumor originating from the meninges, the membranous layers surrounding the CNS .... , some types of sarcoma Sarcoma A sarcoma is a cancer that arises from transformed cells in one of a number of tissues that develop from embryonic mesoderm. Thus, sarcomas include tumors of bone, cartilage, fat, muscle, vascular, and hematopoietic tissues...
Factor VIII Factor VIII Factor VIII is an essential blood clotting factor also known as anti-hemophilic factor . In humans, Factor VIII is encoded by the F8 gene... , CD31 CD31 Platelet endothelial cell adhesion molecule also known as cluster of differentiation 31 is a protein that in human is encoded by the PECAM1 gene found on chromosome 17...  FL1 FL1 FL1 is an initialism that may stand for:* Football League One* A technical standard for the rating of Flashlights* A model of the Chinese Silkworm * A taxicab, one of the List of Austin motor cars...	vascular sarcoma
Glial fibrillary acidic protein Glial fibrillary acidic protein Glial fibrillary acidic protein is an intermediate filament protein that was thought to be specific for astrocytes in the central nervous system . Later, it was shown that GFAP is also expressed by other cell types in CNS, including ependymal cells...  (GFAP)	glioma Glioma A glioma is a type of tumor that starts in the brain or spine. It is called a glioma because it arises from glial cells. The most common site of gliomas is the brain.-By type of cell:...  (astrocytoma Astrocytoma Astrocytomas are a type of neoplasm of the brain. They originate in a particular kind of glial-cells, star-shaped brain cells in the cerebrum called astrocytes. This type of tumor does not usually spread outside the brain and spinal cord and it does not usually affect other organs... , ependymoma Ependymoma Ependymoma is a tumor that arises from the ependyma, a tissue of the central nervous system. Usually, in pediatric cases the location is intracranial, while in adults it is spinal. The common location of intracranial ependymoma is the fourth ventricle... )
Gross cystic disease fluid protein (GCDFP-15)	breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas... , ovarian cancer Ovarian cancer Ovarian cancer is a cancerous growth arising from the ovary. Symptoms are frequently very subtle early on and may include: bloating, pelvic pain, difficulty eating and frequent urination, and are easily confused with other illnesses.... , salivary gland cancer Salivary gland cancer Salivary gland cancer is a cancer that forms in tissues of a salivary gland. The salivary glands are classified as major and minor. The major salivary glands consist of the parotid, submandibular, and sublingual glands. The minor glands include small mucus-secreting glands located throughout the...
HMB-45 HMB-45 HMB-45 is a monoclonal antibody that reacts against an antigen present in melanocytic tumors such as melanomas. It is used in anatomic pathology as a marker for such tumors....	melanoma Melanoma Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye... , PEComa PEComa In oncology, PEComa, also PEC tumour and perivascular epithelioid cell tumour, is a family of mesenchymal tumours consisting of perivascular epithelioid cells . These are rare tumours that can occur in any part of the human body....  (for example angiomyolipoma Angiomyolipoma Angiomyolipoma are the most common benign tumour of the kidney and are composed of blood vessels, smooth muscle cells and fat cells. Angiomyolipoma are strongly associated with the genetic disease tuberous sclerosis, in which most individuals will have several angiomyolipoma affecting both kidneys... ), clear cell carcinoma Clear cell adenocarcinoma Clear cell adenocarcinoma or mesonephroma is a rare type of adenocarcinoma. It usually affects cells in the female genital tract. Vaginal clear cell adenoma is common in women in their late teens and early 20's whose mothers took diethylstilbestrol during pregnancy.Some of these cancers may not... , adrenocortical carcinoma Adrenocortical carcinoma Adrenocortical carcinoma, also adrenal cortical carcinoma and adrenal cortex cancer, is an aggressive cancer originating in the cortex of the adrenal gland. Adrenocortical carcinoma is a rare tumor, with incidence of 1-2 per million population annually...
Human chorionic gonadotropin Human chorionic gonadotropin Human chorionic gonadotropin or human chorionic gonadotrophin is a glycoprotein hormone produced during pregnancy that is made by the developing embryo after conception and later by the syncytiotrophoblast .. Some tumors make this hormone; measured elevated levels when the patient is not...  (hCG)	gestational trophoblastic disease Gestational trophoblastic disease Gestational trophoblastic disease is a term used for a group of pregnancy-related tumours. These tumours are rare, and they appear when cells in the womb start to grow out of control. The cells that form gestational trophoblastic tumours are called trophoblasts and come from tissue that grows to... , germ cell tumor Germ cell tumor A germ cell tumor is a neoplasm derived from germ cells. Germ cell tumors can be cancerous or non-cancerous tumors. Germ cells normally occur inside the gonads... , carcinoma Carcinoma Carcinoma is the medical term for the most common type of cancer occurring in humans. Put simply, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during...
immunoglobulin	lymphoma Lymphoma Lymphoma is a cancer in the lymphatic cells of the immune system. Typically, lymphomas present as a solid tumor of lymphoid cells. Treatment might involve chemotherapy and in some cases radiotherapy and/or bone marrow transplantation, and can be curable depending on the histology, type, and stage... , leukemia Leukemia Leukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases...
inhibin	sex cord-gonadal stromal tumour, adrenocortical carcinoma Adrenocortical carcinoma Adrenocortical carcinoma, also adrenal cortical carcinoma and adrenal cortex cancer, is an aggressive cancer originating in the cortex of the adrenal gland. Adrenocortical carcinoma is a rare tumor, with incidence of 1-2 per million population annually... , hemangioblastoma Hemangioblastoma Hemangioblastomas are tumors of the central nervous system that originate from the vascular system usually during middle-age. Sometimes these tumors occur in other sites such as the spinal cord and retina...
keratin Keratin Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...  (various types)	carcinoma Carcinoma Carcinoma is the medical term for the most common type of cancer occurring in humans. Put simply, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during... , some types of sarcoma Sarcoma A sarcoma is a cancer that arises from transformed cells in one of a number of tissues that develop from embryonic mesoderm. Thus, sarcomas include tumors of bone, cartilage, fat, muscle, vascular, and hematopoietic tissues...
PTPRC (CD45)	lymphoma Lymphoma Lymphoma is a cancer in the lymphatic cells of the immune system. Typically, lymphomas present as a solid tumor of lymphoid cells. Treatment might involve chemotherapy and in some cases radiotherapy and/or bone marrow transplantation, and can be curable depending on the histology, type, and stage... , leukemia Leukemia Leukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases... , histiocytic tumor
lymphocyte marker (various types	lymphoma Lymphoma Lymphoma is a cancer in the lymphatic cells of the immune system. Typically, lymphomas present as a solid tumor of lymphoid cells. Treatment might involve chemotherapy and in some cases radiotherapy and/or bone marrow transplantation, and can be curable depending on the histology, type, and stage... , leukemia Leukemia Leukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases...
MART-1 MART-1 MART-1 / Melan-A is a protein antigen found on melanocytes. Antibodies against the antigen are used in the medical specialty of anatomic pathology in order to recognize cells of melanocytic differentiation, useful for the diagnosis of a melanoma...  (Melan-A)	melanoma Melanoma Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye... , steroid-producing tumors (adrenocortical carcinoma Adrenocortical carcinoma Adrenocortical carcinoma, also adrenal cortical carcinoma and adrenal cortex cancer, is an aggressive cancer originating in the cortex of the adrenal gland. Adrenocortical carcinoma is a rare tumor, with incidence of 1-2 per million population annually... , gonadal tumor)
Myo D1	rhabdomyosarcoma Rhabdomyosarcoma A rhabdomyosarcoma is a type of cancer, specifically a sarcoma , in which the cancer cells are thought to arise from skeletal muscle progenitors. It can also be found attached to muscle tissue, wrapped around intestines, or in any anatomic location... , small, round, blue cell tumour
muscle-specific actin (MSA)	myosarcoma Myosarcoma Myosarcoma is a malignant muscle tumor.Leiomyosarcoma refers to sarcoma of smooth muscle, and rhabdomyosarcoma refers to sarcoma of striated muscle. However, the term myosarcoma itself still appears in the literature....  (leiomyosarcoma Leiomyosarcoma Leiomyosarcoma , aka LMS, is a malignant cancer of smooth muscle.... , rhabdomyosarcoma Rhabdomyosarcoma A rhabdomyosarcoma is a type of cancer, specifically a sarcoma , in which the cancer cells are thought to arise from skeletal muscle progenitors. It can also be found attached to muscle tissue, wrapped around intestines, or in any anatomic location... )
neurofilament Neurofilament Neurofilaments are the 10 nanometer intermediate filaments found specifically in neurons. They are a major component of the cell's cytoskeleton, and provide support for normal axonal radial growth...	neuroendocrine tumor, small-cell carcinoma of the lung
neuron-specific enolase (NSE)	neuroendocrine tumor, small-cell carcinoma of the lung, breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
placental alkaline phosphatase (PLAP)	seminoma, dysgerminoma Dysgerminoma A dysgerminoma is a type of germ cell tumor; it usually is malignant and usually occurs in the ovary.A tumor of the identical histology but not occurring in the ovary may be described by an alternate name: seminoma in the testis or germinoma in the central nervous system or other parts of the... , embryonal carcinoma Embryonal carcinoma Embryonal carcinoma is a relatively uncommon type of germ cell tumour that occurs in the ovaries and testes.-Ovarian embryonal carcinoma:In the ovary, embryonal carcinoma is quite rare, amounting to approximately three percent of ovarian germ cell tumours. The median age at diagnosis is 15 years...
prostate-specific antigen	prostate Prostate The prostate is a compound tubuloalveolar exocrine gland of the male reproductive system in most mammals....
S100 protein	melanoma Melanoma Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye... , sarcoma Sarcoma A sarcoma is a cancer that arises from transformed cells in one of a number of tissues that develop from embryonic mesoderm. Thus, sarcomas include tumors of bone, cartilage, fat, muscle, vascular, and hematopoietic tissues...  (neurosarcoma, lipoma Lipoma A lipoma is a benign tumor composed of adipose tissue. It is the most common form of soft tissue tumor. Lipomas are soft to the touch, usually movable, and are generally painless. Many lipomas are small but can enlarge to sizes greater than six centimeters. Lipomas are commonly found in adults... , chondrosarcoma Chondrosarcoma Chondrosarcoma is a cancer composed of cells derived from transformed cells that produce cartilage. Chondrosarcoma is a member of a category of "soft tissue" malignancies known as sarcomas. About 30% of skeletal system cancers are chondrosarcomas... ), astrocytoma Astrocytoma Astrocytomas are a type of neoplasm of the brain. They originate in a particular kind of glial-cells, star-shaped brain cells in the cerebrum called astrocytes. This type of tumor does not usually spread outside the brain and spinal cord and it does not usually affect other organs... , gastrointestinal stromal tumor Gastrointestinal stromal tumor A gastrointestinal stromal tumor is one of the most common mesenchymal tumors of the gastrointestinal tract... , salivary gland cancer Salivary gland cancer Salivary gland cancer is a cancer that forms in tissues of a salivary gland. The salivary glands are classified as major and minor. The major salivary glands consist of the parotid, submandibular, and sublingual glands. The minor glands include small mucus-secreting glands located throughout the... , some types of adenocarcinoma Adenocarcinoma Adenocarcinoma is a cancer of an epithelium that originates in glandular tissue. Epithelial tissue includes, but is not limited to, the surface layer of skin, glands and a variety of other tissue that lines the cavities and organs of the body. Epithelium can be derived embryologically from... , histiocytic tumor (dendritic cell Dendritic cell Dendritic cells are immune cells forming part of the mammalian immune system. Their main function is to process antigen material and present it on the surface to other cells of the immune system. That is, dendritic cells function as antigen-presenting cells... , macrophage Macrophage Macrophages are cells produced by the differentiation of monocytes in tissues. Human macrophages are about in diameter. Monocytes and macrophages are phagocytes. Macrophages function in both non-specific defense as well as help initiate specific defense mechanisms of vertebrate animals... )
smooth muscle actin (SMA)	gastrointestinal stromal tumor Gastrointestinal stromal tumor A gastrointestinal stromal tumor is one of the most common mesenchymal tumors of the gastrointestinal tract... , leiomyosarcoma Leiomyosarcoma Leiomyosarcoma , aka LMS, is a malignant cancer of smooth muscle.... , PEComa PEComa In oncology, PEComa, also PEC tumour and perivascular epithelioid cell tumour, is a family of mesenchymal tumours consisting of perivascular epithelioid cells . These are rare tumours that can occur in any part of the human body....
synaptophysin Synaptophysin Synaptophysin also known as the major synaptic vesicle protein p38 is a protein that in humans is encoded by the SYP gene.-Genomics:...	neuroendocrine tumor
thyroglobulin Thyroglobulin Thyroglobulin is a 660 kDa, dimeric protein produced by and used entirely within the thyroid gland. In earlier literature, Tg was referred to as colloid....	thyroid cancer Thyroid cancer Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...  (but not in medullary thyroid cancer Medullary thyroid cancer Medullary thyroid cancer is a form of thyroid carcinoma which originates from the parafollicular cells , which produce the hormone calcitonin.... )
thyroid transcription factor-1	all types of thyroid cancer Thyroid cancer Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected... , lung cancer Lung cancer Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
Tumor M2-PK Tumor M2-PK Tumor M2-PK is a synonym for the dimeric form of the pyruvate kinase isoenzyme type M2 , a key enzyme within tumor metabolism. Tumor M2-PK can be elevated in many tumor types, rather than being an organ-specific tumor marker such as PSA...	colorectal cancer Colorectal cancer Colorectal cancer, commonly known as bowel cancer, is a cancer caused by uncontrolled cell growth , in the colon, rectum, or vermiform appendix. Colorectal cancer is clinically distinct from anal cancer, which affects the anus.... , Breast cancer Breast cancer Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas... , renal cell carcinoma Renal cell carcinoma Renal cell carcinoma is a kidney cancer that originates in the lining of the proximal convoluted tubule, the very small tubes in the kidney that filter the blood and remove waste products. RCC is the most common type of kidney cancer in adults, responsible for approximately 80% of cases...  Lung cancer Lung cancer Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary... , Pancreatic cancer Pancreatic cancer Pancreatic cancer refers to a malignant neoplasm of the pancreas. The most common type of pancreatic cancer, accounting for 95% of these tumors is adenocarcinoma, which arises within the exocrine component of the pancreas. A minority arises from the islet cells and is classified as a... , Esophageal Cancer Esophageal cancer Esophageal cancer is malignancy of the esophagus. There are various subtypes, primarily squamous cell cancer and adenocarcinoma . Squamous cell cancer arises from the cells that line the upper part of the esophagus... , Stomach Cancer Stomach cancer Gastric cancer, commonly referred to as stomach cancer, can develop in any part of the stomach and may spread throughout the stomach and to other organs; particularly the esophagus, lungs, lymph nodes, and the liver... ,Cervical Cancer Cervical cancer Cervical cancer is malignant neoplasm of the cervix uteri or cervical area. One of the most common symptoms is abnormal vaginal bleeding, but in some cases there may be no obvious symptoms until the cancer is in its advanced stages... , Ovarian Cancer Ovarian cancer Ovarian cancer is a cancerous growth arising from the ovary. Symptoms are frequently very subtle early on and may include: bloating, pelvic pain, difficulty eating and frequent urination, and are easily confused with other illnesses.... ,
vimentin Vimentin Vimentin is a type III intermediate filament protein that is expressed in mesenchymal cells. IF proteins are found in all metazoan cells as well as bacteria. IF, along with tubulin-based microtubules and actin-based microfilaments, comprise the cytoskeleton...	sarcoma Sarcoma A sarcoma is a cancer that arises from transformed cells in one of a number of tissues that develop from embryonic mesoderm. Thus, sarcomas include tumors of bone, cartilage, fat, muscle, vascular, and hematopoietic tissues... , renal cell carcinoma Renal cell carcinoma Renal cell carcinoma is a kidney cancer that originates in the lining of the proximal convoluted tubule, the very small tubes in the kidney that filter the blood and remove waste products. RCC is the most common type of kidney cancer in adults, responsible for approximately 80% of cases... , endometrial cancer Endometrial cancer Endometrial cancer refers to several types of malignancies that arise from the endometrium, or lining, of the uterus. Endometrial cancers are the most common gynecologic cancers in the United States, with over 35,000 women diagnosed each year. The incidence is on a slow rise secondary to the... , lung carcinoma, lymphoma Lymphoma Lymphoma is a cancer in the lymphatic cells of the immune system. Typically, lymphomas present as a solid tumor of lymphoid cells. Treatment might involve chemotherapy and in some cases radiotherapy and/or bone marrow transplantation, and can be curable depending on the histology, type, and stage... , leukemia Leukemia Leukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases... , melanoma Melanoma Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...

Sources of inaccuracy

The high dose hook effect is an artefact of tumor marker immunoassay kits, that causes the reported quantity of tumor marker to be incorrectly low when the quantity is high. An undetected hook effect may cause delayed recognition of a tumor. The hook effect can be detected by analyzing serial dilutions. Absent hook effect, reported quantities of tumor marker in a serial dilution should be proportional to the dilution.