primitive neuroectodermal tumours |
A type of brain tumour. Prenatal diagnosis: diagnosis before birth. Methods for prenatal diagnosis include ultrasound (of the uterus, placenta and developing foetus), chorionic villus sampling to obtain tissue for chromosome or biochemical analysis, amniocentesis to obtain amniotic fluid for the analysis of chromosmes, enzymes, DNA, etc. A growing number of birth defects and diseases are now amenable to prenatal diagnosis. Also called antenatal diagnosis.
(12 Dec 1998) |
melanotic neuroectodermal tumour of infancy |
A benign neoplasm of neuroectodermal origin that most often involves the anterior maxilla of infants in the first year of life. It presents clinically as a rapidly growing blue-black lesion producing a destructive radiolucency; histologically, it is characterised by small round undifferentiated tumour cells interspersed with larger polyhedral melanin-producing cells arranged in an alveolar configuration.
Synonym: melanoameloblastoma, pigmented ameloblastoma, pigmented epulis, progonoma of jaw, retinal anlage tumour.
(05 Mar 2000) |
primitive neuroectodermal tumour |
A designation used to refer to a group of morphologically similar embryonal neoplasms that arise in intracranial and peripheral sites of the nervous system and which may show various degrees of cellular differentiation; includes medulloblastoma, pineoblastoma, etc.
(05 Mar 2000) |
neuroectodermal |
Relating to the neuroectoderm.
(05 Mar 2000) |
neuroectodermal junction |
The margin of the embryonic neural plate separating it from the embryonic ectoderm; cells from this region form the neural crest.
Synonym: neurosomatic junction.
(05 Mar 2000) |
neuroectodermal tumour, melanotic |
A benign, rapidly growing, deeply pigmented tumour of the jaw and occasionally of other sites, consisting of an infiltrating mass of cells arranged in an alveolar pattern, and occurring almost exclusively in infants. Its source of origin is in dispute, the various theories giving rise to its several names.
(12 Dec 1998) |
neuroectodermal tumour, peripheral |
A heterogeneous group of malignant neoplasms arising in either supportive structures or neuronal tissue. They occur in adolescents and young adults. This tumour shares a number of characteristics with ewing's sarcoma: it is highly cellular and consists of a monotonous pattern of primitive-appearing round cells. The chest wall is the most common site but the trunk, abdomen, and pelvis are other primary sites.
(12 Dec 1998) |
neuroectodermal tumour, primitive |
A malignant brain tumour sharing common features and biologic properties with medulloblastoma. Some pathologists and clinicians use the terms interchangeably: they both can disseminate throughout the nervous system and, in some cases, systemically. most lesions arise from the posterior fossa in children under five years of age. The tumour often produces hydrocephalus and symptoms of increased intracranial pressure. Papilledema is often present.
(12 Dec 1998) |
benign liver tumours |
<radiology> EPITHELIAL TUMORS, nodular transformation, focal nodular hyperplasia, hepatocellular adenoma, MESENCHYMAL TUMORS, lipoma, myelolipoma, angiomyolipoma, leiomyoma, infantile haemangioendothelioma, haemangioma, benign mesothelioma, MIXED TISSUE TUMORS, mesenchymal hamartoma, benign teratoma, MISCELLANEOUS, adrenal rest tumours, pancreatic rest
(12 Dec 1998) |
brain tumours |
Can be malignant or benign and can occur at any age. Primary brain tumours initially form in the brain tissue. Secondary brain tumours are cancers that have spread to the brain tissue (metastasized) from tissue elsewhere in the body.
(12 Dec 1998) |
pancreatic isleT-cell tumours |
<radiology> Insulinoma (beta-cell), usually solitary, 85% benign, gastrinoma, small, slow-growing, multiple, 60% malignant, Zollinger-Ellison syndrome: mult. Intractable ulcers, VIPoma, vasoactive intestinal peptide (VIP), WDHA syndrome: watery diarrhoea, hypokalaemia, achlorhydria, Verner-Morrison syndrome, glucagonoma, hyperglycaemia, migratory necrolytic erythema APUDomas, associated with MEN-1
(12 Dec 1998) |
malignant liver tumours |
<radiology> EPITHELIAL TUMORS, hepatocellular, hepatoblastoma (7%), hepatocellular carcinoma (HCC) (75%), cholangiocellular (6%), cholangiocarcinomarcinoma, cystadenocarcinoma, MESENCHYMAL TUMORS, tumours of blood vessels, angiosarcoma, haemangioendothelioma, other tumours, embryonal sarcoma, fibrosarcoma, TUMORS OF MUSCLE TISSUE, leiomyosarcoma, rhabdomyosarcoma, MISCELLANEOUS, carcinosarcoma, teratoma, yolk sac tumour, carcinoid, squamous carcinoma, primary lymphoma see: benign liver tumours
(12 Dec 1998) |
venereal tumours, veterinary |
Tumours most commonly seen on or near the genitalia. They are venereal, most likely transmitted through transplantation of cells by contact. Metastases have been reported. Spontaneous regression may occur.
(12 Dec 1998) |
giant cell tumours |
Tumours of bone tissue or synovial or other soft tissue characterised by the presence of giant cells. The most common are giant cell tumour of tendon sheath and giant cell tumour of bone.
(12 Dec 1998) |
pineal region tumours |
Type of brain tumours.
(12 Dec 1998) |