Odontogenic tumour Health Dictionary

Odontogenic Tumour: From 1 Different Sources

any one of a group of neoplasm tumour-like malformations arising from odontogenic tissues or their remnants. The most important example is the *ameloblastoma.

Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Tumour

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

Brain Tumour

An abnormal growth in or on the brain. Tumours may be primary growths arising directly from tissues within the skull or metastases (secondary growths) that have spread from tumours elsewhere in the body. The cause of primary brain tumours is not known. About 60 per cent are gliomas (frequently cancerous), which arise from the brain tissue. Other primary tumours include meningiomas, acoustic neuromas, and pituitary tumours. Most of these tumours are noncancerous, but their size can cause local damage. Certain types of primary brain tumour mainly affect children. These include 2 types of glioma called medulloblastoma and cerebellar astrocytoma. Primary brain tumours virtually never spread (metastasize) outside the central nervous system.

Symptoms include muscle weakness, loss of vision, or other sensory disturbances, speech difficulties, and epileptic seizures. Increased pressure within the skull can cause headache, visual disturbances, vomiting, and impaired mental functioning. Hydrocephalus may occur.

When possible, primary tumours are removed by surgery after opening the skull (see craniotomy).

In cases where a tumour cannot be completely removed, as much as possible of it will be cut away to relieve pressure.

For primary and secondary tumours, radiotherapy or anticancer drugs may also be given.

Corticosteroid drugs are often prescribed temporarily to reduce the size of a tumour and associated brain swelling.... brain tumour

Desmoid Tumour

A growth, usually in the abdominal wall.

The tumour is hard, with a well-defined edge.

The tumours occur most frequently in women who have had children.

They may also arise at the sites of old surgical incisions.

Surgical removal is the usual treatment.... desmoid tumour

Germ Cell 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

Glomus Tumour

A small, bluish swelling in the skin, usually on a finger or toe near or under the nail, which is tender to touch and more painful if the limb is hot or cold.

The cause is overgrowth of the nerve structures that normally control blood flow and temperature in the skin.

The tumours are harmless but are surgically removed.... glomus tumour

Mixed Tumour

A neoplasm with a number of different cell types undergoing cancerous change.... mixed tumour

Anti-tumours

See: ANTI-NEOPLASTICS. ... anti-tumours

Adrenal Tumours

Cancerous or noncancerous tumours in the adrenal glands, usually causing excess secretion of hormones. Adrenal tumours are rare. Tumours of the adrenal cortex may secrete aldosterone, causing primary aldosteronism, or hydrocortisone, causing Cushing’s syndrome. Tumours of the medulla may cause excess secretion of adrenaline and noradrenaline. Two types of tumour affect the medulla: phaeochromocytoma and neuroblastoma, which affects children. These tumours cause intermittent hypertension and sweating attacks. Surgical removal of a tumour usually cures these conditions.... adrenal tumours

Apud Cell Tumour

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

Bladder Tumours

Growths originating in the inner lining of the bladder. Many are papillomas (small wart-like growths), which tend to recur and will eventually become cancerous. Other, more malignant, growths may extend not only into the bladder cavity but may also spread through the bladder wall to involve nearby organs such as the colon, rectum, prostate gland, or uterus.

Bladder cancer is more common in smokers and workers in the dye and rubber industries. Haematuria (blood in the urine) is the main symptom of bladder cancer. A tumour may obstruct the entry of a ureter into the bladder, causing back pressure and pain in the kidney region, or may obstruct the urethral exit, causing difficulty in passing, or retention of, urine.

Bladder tumours are diagnosed using cystoscopy and biopsy of the abnormal area. If small, they can be treated by heat or surgically during cystoscopy. They tend to recur at the same or other sites within the bladder, so that regular follow-up cystoscopy is needed. Bladder tumours that have spread through the bladder wall may be treated by radiotherapy or by surgical removal of part or all of the bladder.... bladder tumours

Bone Tumour

A bone swelling that may be cancerous (see bone cancer) or noncancerous.

The most common type of noncancerous bone tumour is an osteochondroma.

Other types are osteoma and chondroma (see chondromatosis).

Treatment is only necessary if the tumour becomes very large or causes symptoms by pressing on other structures.

In such cases, the tumour can be removed by surgery.

Osteoclastoma (also called a giant cell tumour), which usually occurs in the arm or leg of a young adult, is tender and painful and has to be removed.... bone tumour

Dermoid Tumour

See dermoid cyst.... dermoid tumour

Intestine, Tumours Of

Cancerous or noncancerous growths in the intestine. Cancerous tumours commonly affect the large intestine (see colon, cancer of; rectum, cancer of); the small intestine is only rarely affected. Lymphomas and carcinoid tumours (leading to carcinoid syndrome) may sometimes develop in the intestine; noncancerous tumours include polyps in the colon, and adenomas, leiomyomas, lipomas, and angiomas in the small intestine.... intestine, tumours of

Eye Tumours

Tumours of the eye are rare. When eye tumours do occur, they are usually cancerous and painless.

Retinoblastoma is a cancerous tumour of the retina that occurs in one or both eyes and most often affects children. It may be treated by radiotherapy, laser treatment, or cryosurgery, but the eye may have to be removed to prevent spread of the tumour.

Malignant melanoma is a cancer of the choroid. It usually affects older people. There are no symptoms in the early stages, but it eventually causes retinal detachment and distortion of vision. Small tumours can be treated by laser, but the eye may need to be removed to avoid spread of the tumour.

Secondary eye tumours occur when cancer elsewhere in the body spreads to the eye. Symptoms depend on the tumour’s location and growth rate. It may be controlled by radiotherapy.

Basal cell carcinoma is the most common type of tumour affecting the eyelid. It usually has a crusty central crater and a rolled edge. In the early stages, treatment may be possible by surgery, radiotherapy, or cryosurgery.... eye tumours

Lung Tumours

Growths in the lungs. These tumours may be either cancerous (see lung cancer) or noncancerous.Cancerous lung tumours are usually associated with tobacco-smoking.

Noncancerous tumours occur less frequently than cancers.

The most common form of noncancerous tumour is a bronchial adenoma, which arises in the lining of a bronchus.

Adenomas often cause bronchial obstruction; affected people may also cough up blood.

Treatment involves surgical removal of the tumour.

Other rare noncancerous tumours include fibromas (which consist of fibrous tissue) and lipomas (which consist of fatty tissue).

No treatment is necessary unless the tumours are causing problems.... lung tumours

Pituitary Tumours

Growths in the pituitary gland. Pituitary tumours are rare, and mostly noncancerous, but tumour enlargement can put pressure on the optic nerves, causing visual defects.

The causes of pituitary tumours are unknown. They may lead to inadequate hormone production, causing problems such as cessation of menstrual periods or reduced sperm production. They may also cause the gland to produce excess hormone. Overproduction of growth hormone causes gigantism or acromegaly; too much thyroid-stimulating hormone (TSH) can lead to hyperthyroidism. Investigations include blood tests, X-rays, MRI of the pituitary, and usually also vision tests. Treatment may be by surgical removal of the tumour, radiotherapy, hormone replacement, or a combination of these techniques. The drug bromocriptine may be used; it can reduce production of certain hormones and shrink some tumours.... pituitary tumours

Skin Tumours

A growth on or in the skin that may be cancerous (see skin cancer) or noncancerous.

Keratoses and squamous papillomas are common types of noncancerous tumour; other types include sebaceous cysts, cutaneous horns, keratoacanthomas, and haemangiomas.... skin tumours

Trophoblastic Tumour

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

Tumour-specific Antigen

A substance secreted by a specific type of tumour that can be detected in the blood and may be used to help monitor a patient’s response to therapy.

Alpha-fetoprotein is an example of a tumour-specific antigen.... tumour-specific antigen

Wilms’ Tumour

A type of kidney cancer, also called nephroblastoma, that occurs mainly in children.... wilms’ tumour

Cerebral Tumour

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

Endodermal Sinus 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

Gastrointestinal Stromal 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

Grawitz Tumour

see renal cell carcinoma. [P. A. Grawitz (1850–1932), German pathologist]... grawitz tumour

Hilar Cell 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

Hürthle Cell Tumour

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

Islet 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

Klatskin Tumour

see cholangiocarcinoma. [G. Klatskin (20th century), US physician]... klatskin tumour

Krukenberg 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

Leydig 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

Lindau’s Tumour

see haemangioblastoma. [A. Lindau (1892–1958), Swedish pathologist]... lindau’s tumour

Phantom Tumour

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

Raspberry Tumour

an *adenoma of the umbilicus.... raspberry tumour

Sternomastoid 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

Tumour-associated Antigen

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.... tumour-associated antigen

Tumour-infiltrating Lymphocyte

(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

Tumour Marker

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

Tumour Necrosis Factor

(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

Warthin’s Tumour

(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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Odontogenic tumour Health Dictionary

Odontogenic Tumour: From 1 Different Sources

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