pineal tumours |
<radiology> SIGNS: aqueductal obstruction most likely to be hydrocephalus, paralysis of upward gaze (due to pressure on quarigeminal plate), precocious puberty, symptoms of hypothalamic, thalamic, cerebellar or pyramidal lesion TYPES: germ-cell (teratoid) tumours, teratoma, germinoma / atypical teratoma, endodermal sinus (yolk sac) tumour, choriocarcinoma, pineal-cell tumours, pineocytoma, pineo---, others, glioma, ganglioneuroma, ganglioglioma
(12 Dec 1998) |
plant tumours |
A localised proliferation of plant tissue forming a swelling or outgrowth, commonly with a characteristic shape and unlike any organ of the normal plant. Plant tumours or galls usually form in response to the action of a pathogen or a pest.
(12 Dec 1998) |
posterior fossa tumours |
<radiology> Midline, medulloblastoma (hyperdense, enhances), astrocytoma (hypodense, enhances), 4th ventricle, ependymoma (most common, slow-growing, expands ventricle), medulloblastoma (usually obliterates ventricular cavity), choroid plexus papilloma (more common in lateral ventricles)
(12 Dec 1998) |
nerve sheath tumours |
Tumours arising in the sheath surrounding the axon of some nerve cells and formed by the plasma membrane of schwann cells in the peripheral nervous sytem and by oligodendrocytes in the central nervous system. Neurofibromas and neurilemmomas are the most commonly occurring tumours of this type.
(12 Dec 1998) |
neuroendocrine tumours |
Tumours whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumours include ectopic hormone production (often via apud cells), the presence of tumour-associated antigens, and isozyme composition.
(12 Dec 1998) |
desmoplastic tumours |
<radiology> Carcinoid of small bowel or colon, Hodgkin's lymphoma, scirrhous gastric carcinoma
(12 Dec 1998) |
developmental brain tumours |
<radiology> 1% of all brain tumours, germ-cell tumours, epidermoid more than dermoid more than > Teratoma, usually midline, craniopharyngioma, colloid cyst, lipoma, hamartoma
(12 Dec 1998) |
duodenal tumours |
<radiology> 90% benign, in 2nd and 3rd portion: 50% malignant, in 4th portion: most malignant, of malignancies: 80-90% leading to adenocarcinoma Differential diagnosis: benign, tubular adenoma, leiomyoma, lipoma, hamartoma (Peutz-Jeghers), prolapsed antral polyp, Brunner's gland adenoma (really hypertrophy and hyperplasia), malignant, adenocarcinoma (80-90% of malignant lesions), villous adenoma (pre-malignant), carcinoid / isleT-cell tumour
(12 Dec 1998) |
infantile brain tumours |
<radiology> Can be present at birth: choroid plexus papilloma, medulloblastoma, craniopharyngioma, ependymoma, astrocytoma, teratoma
(12 Dec 1998) |
odontogenic tumours |
Neoplasms produced from tooth-forming tissues.
(12 Dec 1998) |
ovarian stromal tumours |
<radiology> Age 20 - 50 yrs, 20% of all ovarian tumours, fibroma / fibrosarcoma, granulosa-theca cell tumour, with or without oestrogens most likely to be precocious puberty, endometrial hyperplasia/carcinoma, fibrocystic breast disease, Sertoli-Leydig cell tumour, aka: arrhenoblastoma, with or without androgens most likely to be masculinization, may be mixed type
(12 Dec 1998) |
ovarian tumours |
<radiology> Before age 45 most likely to be 98% benign, 2/3 of cancers in ages 40 - 65 yrs see also: ovarian stromal tumours
(12 Dec 1998) |
lymphatic vessel tumours |
Neoplasms composed of lymphoid tissue, a lattice work of reticular tissue the interspaces of which contain lymphocytes. The concept does not refer to neoplasms located in lymphatic vessels.
(12 Dec 1998) |