Tumour-associated Antigen: From 1 Different Sources
a protein produced by cancer cells. Its presence in the blood can be revealed by means of a simple blood test, aiding the diagnosis of malignant melanoma and other cancers at their earliest – and most treatable – stages of development.
A substance, usually a protein, that induces the formation of defending antibodies. Example: bacterial toxins, Juniper pollen (in allergies). Auto-immune disorders can occur when antibodies are formed against normal proteins created within the body.... antigen
A mass or swelling. The lump can be a neoplasm (benign or malignant) or a tumour can be a mass due to an infection or inflammation.... tumour
Also called nephroblastoma. This is the commonest kidney tumour in infancy. It is a malignant tumour, which occurs in around one per 10,000 live births. The survival rate with modern treatment (removal of the kidney followed by radiotherapy and chemotherapy) is now around 80 per cent.... wilms’ tumour
A growth comprised of immature sperm cells in the male testis or of immature ova in the female ovary. A seminoma is one type of germ cell tumour (see testis, cancer of).... germ cell tumour
See HLA SYSTEM.... human leucocyte antigen (hla)
A neoplasm with a number of different cell types undergoing cancerous change.... mixed tumour
An ENZYME produced by glandular tissue in the PROSTATE GLAND. When the gland enlarges (see PROSTATE, DISEASES OF), greater amounts of PSA are secreted, raising the concentration of the enzyme in the blood. This is especially so in cancer of the prostate, and testing the level of PSA is an indicator that the disease may be present. There is much controversy about the use of PSA as a screening test. Its proponents claim that its use reduces deaths from prostate cancer; its opponents suggest that it does this only by bringing to light many cases that needed no treatment and would not have caused death in any case. Further, if the level of PSA is very high, the disease is already advanced; where the result is equivocal it is uncertain whether the bene?ts of treatment outweigh the risks.... prostate specific antigen (psa)
Substances, usually harmful, that when entering the body stimulate the immune system to produce antibodies. Invaders may be polio virus, typhoid bacillus, or chain-like streptococcal bacteria – the usual pus-forming type found in infected wounds, or toxins they release into the blood stream. ... antigens
A growth composed of cells that produce various hormones. These cells, amine precursor uptake and decarboxylation (APUD) cells, occur in different parts of the body. Some tumours of the thyroid gland, pancreas, and lungs are cell tumours, as are a carcinoid tumour (see carcinoid syndrome) and phaeochromocytoma (a type of adrenal tumour).... apud cell tumour
See dermoid cyst.... dermoid tumour
(HLA) A type of protein belonging to the group known as histocompatibility antigens, which play a role in the immune system.... human leukocyte antigen
A growth arising from the tissues that develop into the placenta. The most common type of trophoblastic tumour is a hydatidiform mole. (See also choriocarcinoma.)... trophoblastic tumour
A type of kidney cancer, also called nephroblastoma, that occurs mainly in children.... wilms’ tumour
(APC) a cell, such as a *dendritic cell or a *macrophage, that processes antigen for presentation to a T lymphocytes (see helper T cell).... antigen-presenting cell
another name for the *hepatitis B antigen, which was first discovered in the blood of an Australian aborigine. This disease is caused by a virus of which the Australia antigen forms part.... australia antigen
(CEA) a protein produced in the fetus but not in normal adult life. It may be produced by carcinomas, particularly of the colon, and is a rather insensitive marker of malignancy. It is an example of an *oncofetal antigen that is used as a *tumour marker, particularly in the follow-up of colorectal cancer.... carcino-embryonic antigen
an abnormal multiplication of brain cells. Any tumorous swelling tends to compress or even destroy the healthy brain cells surrounding it and – because of the rigid closed nature of the skull – increases the pressure on the brain tissue. Malignant brain tumours, which are much more common in children than in adults, include *medulloblastomas and *gliomas; these grow rapidly, spreading through the otherwise normal brain tissue and causing progressive neurological disability. Benign tumours, such as *meningiomas, grow slowly and compress the brain tissue. Both benign and malignant tumours commonly cause fits. Benign tumours are often cured by total surgical resection. Malignant tumours may be treated by neurosurgery, chemotherapy, and radiotherapy, but the outcome for most patients remains poor.... cerebral tumour
a rare tumour of fetal remnants of the ovaries or testes. In women it is an aggressive malignant ovarian tumour that develops in adolescence and may secrete alpha-fetoprotein and human chorionic gonadotrophin, which can be used as *tumour markers. It is treated by oophorectomy with adjuvant chemotherapy.... endodermal sinus tumour
(GIST) a rare type of sarcoma arising from the gastrointestinal tract (usually the stomach), characterized by the presence of the receptor c-kit/CD117 on the surface of the tumour cells, which stimulates division of these cells. It displays a wide range of malignant behaviour. Specific treatment is available with *tyrosine kinase inhibitors.... gastrointestinal stromal tumour
see renal cell carcinoma. [P. A. Grawitz (1850–1932), German pathologist]... grawitz tumour
an androgen-producing tumour of the ovary found in older women and often resulting in *virilization. Such tumours are so called as they tend to occur around the area of the ovary where the blood vessels enter (the hilum). They are usually small and are treated by surgical removal, with resolution of most of the symptoms.... hilar cell tumour
see HLA system.... human leucocyte antigen system
a malignant tumour of the thyroid gland that arises from Hürthle (or Askanazy) cells, altered follicular cells of the gland that have large nuclei and stain deeply with eosin (these cells are also found in benign nodules and Hashimoto’s disease). Hürthle cell carcinoma is not as common as papillary, follicular, or anaplastic thyroid carcinomas (see thyroid cancer). [K. W. Hürthle (1860–1945), German histologist]... hürthle cell tumour
any tumour arising in a cell of the pancreatic *islets of Langerhans. These tumours, which include *insulinomas, *glucagonomas, and *somatostatinomas, form one of the two major subclasses of gastrointestinal neuroendocrine tumours, the other being the *carcinoid tumours.... islet cell tumour
a group of antigens that may or may not be present on the surface of red blood cells, forming the basis of a *blood group. This group is important in blood transfusion reactions. [Mrs Kell (20th century), patient in whom they were first demonstrated]... kell antigens
see cholangiocarcinoma. [G. Klatskin (20th century), US physician]... klatskin tumour
a rapidly developing malignant growth in one or (more often) both ovaries. It is caused by the *transcoelomic spread of a primary growth in the stomach or intestine, typically an adenocarcinoma. [F. E. Krukenberg]... krukenberg tumour
a tumour of the *interstitial (Leydig) cells of the testis. Such tumours often secrete testosterone, which in prepubertal boys causes *virilization and precocious puberty.... leydig tumour
see haemangioblastoma. [A. Lindau (1892–1958), Swedish pathologist]... lindau’s tumour
any one of a group of neoplasm tumour-like malformations arising from odontogenic tissues or their remnants. The most important example is the *ameloblastoma.... odontogenic tumour
a protein normally produced only by fetal tissue but often produced by certain tumours. An example is *carcino-embryonic antigen (CEA), which has been used as a *tumour marker, especially in colorectal carcinomas.... oncofetal antigen
1. an accumulation of fluid (pleural effusion) in the lung in patients with heart failure, which resembles a lung tumour on radiological examination. 2. a swelling in the abdomen or elsewhere, caused by local muscular contraction or the accumulation of gases, that mimics a swelling caused by a tumour.... phantom tumour
(PSA) a protease enzyme produced by the glandular epithelium of the prostate. Its effect is to liquefy the semen within the ejaculate. Overall PSA has a half-life of 2–3 days. Increased quantities are secreted when the gland becomes enlarged or inflamed, and levels of PSA in the blood are significantly elevated in cancer of the prostate. Although there is no clear ‘cut-off’ level for normality, over 4 ng/ml in the blood is associated with a 20% risk of prostate cancer, even in patients with normal-feeling prostates on rectal examination. Age-specific PSA reference ranges are often used. Newer PSA assays can measure free PSA and compare it to the total PSA in the blood. Low free:total PSA ratios indicate a greater risk of prostate cancer and improve the discrimination between cancer and benign disease in men with a PSA in the range 4–10 ng/ml. PSA levels tend to be much higher in advanced prostate cancer and the rate of fall on treatment (e.g. after radical prostatectomy or radiotherapy) is a good prognostic indicator of response.... prostate specific antigen
an *adenoma of the umbilicus.... raspberry tumour
a small painless nonmalignant swelling in the lower half of the *sternomastoid muscle, appearing a few days after birth. It occurs when the neck of the fetus is in an abnormal position in the uterus, which interferes with the blood supply to the affected muscle, and it is most common after breech births. The tumour may cause a slight tilt of the head towards the tumour and turning of the face to the other side. This can be corrected by physiotherapy aimed at increasing all movements of the body, but without stretching the neck.... sternomastoid tumour
(TIL) a lymphoid cell that can infiltrate solid tumours. Such cells can be cultured in vitro, in the presence of *interleukin 2, and have been used as vehicles for *tumour necrosis factor in gene therapy trials for cancer.... tumour-infiltrating lymphocyte
a substance produced by a tumour that can be used to aid detection of the tumour and to monitor its size and the effects of treatment. An example is *alpha-fetoprotein, which is used to monitor treatment of malignant *teratomas. See also CA125; CA19-9; carcino-embryonic antigen; human chorionic gonadotrophin.... tumour marker
(TNF) either of two proteins, TNF-? or TNF-?, that function as *cytokines. Produced by macrophages, monocytes, T lymphocytes, and various other cells, they mediate many responses, including inflammation, and have a marked action against tumour cells. Anti-TNF drugs (see cytokine inhibitor) are used in the treatment of several disorders, especially rheumatoid arthritis and ankylosing spondylitis.... tumour necrosis factor
(adenolymphoma) a tumour of the parotid salivary glands, containing epithelial and lymphoid tissues with cystic spaces. [A. S. Warthin (1866–1931), US pathologist]... warthin’s tumour
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