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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Described is a unique mixed intracerebral tumor composed of schwannoma, piloid astrocytoma, and angiomatous malformation. Review of conventional staining methods for distinguishing glial from connective tissue fibrils reveals that Mallory's phosphotungstic acid-hematoxylin (PTAH) method is less specific than is generally recognized. Knowledge of these pitfalls, combined with use of hematoxylin and eosin stains, and reticulum impregnations are currently most useful in making the distinction by light microscopy. Criteria for malignancy of schwannoma and other mesenchymal tumors should be based on number of mitotic figures and invasiveness rather than on pleomorphiam of cells. Prior knowledge of the location of the tumor may lead to diagnosing some schwannomas as other types of tumor.
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PMID:Brain tumors of mixed tissue origin: staining procedures to distinguish glial from connective tissue. 6 42

Serum alpha-fetoprotein (AFP) was measured in 10 cases of primary brain tumors in children (4 cases of medulloblastoma, 4 cases of germ cell tumor and 2 cases of astrocytoma). As a result, elevation in AFP was observed only in a case of embryonal carcinoma that showed partial mixture of germinoma. The absence of AFP elevation in 3 other cases of pure germinoma (atypical teratoma; pinealoma) agrees with reports which describe that, in the germ cell tumor of the gonads, a rise in AFP is not observed in pure seminoma but is found in embryonal carcinoma and endodermal sinus tumor (yolk sac tumor). The fluctuations in AFP in serum and cerebrospinal fluid are considered to be of significance in the diagnosis and treatment of primary intracranial malignant germ cell tumors.
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PMID:Radioimmunoassay of alpha-fetoprotein in children with primary intracranial tumors. 8 37

Six cloned astrocytoma cell lines derived from four ethylnitrosourea-induced F-344 rat gliomas were viewed by scanning electron microscopy in vitro, and two were examined in vivo after transplantation to the intracerebral site. All clones consisted of stellate cells that were reasonably homogeneous within individual glioma lines. Cell membrane features common to all tumor lines included microvilli, blebs, ruffles, and miniridges, mainly confined to perikarya, and filopodia emanating chiefly from cell processes. One cell line demonstrated a profuse, and another cell line a moderate, degree of microvillous development and cell surface roughening, which in one tumor correlated with rapid in vitro cell doubling time. Both cell lines maintained these topographical appearances when transplanted into brain. These results extend the SEM observations of astrocytomas, particularly in cloned ethylnitrosourea-induced tumors in rats. The confirm that distinct variations in cell membrane topography do occur among tumors of this type, probably irrespective of their origin in humans or rats, and irrespective of their mode of genesis as spontaneous, chemically-induced, or virally-induced tumors.
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PMID:Scanning electron microscopy of cloned astrocytic lines derived from ethylnitrosourea-induced rat gliomas. 9 59

Von Recklinghausen's Disease (VRD) is a neurocutaneous, systemic disease characterized by CNS tumors and disorders, cafe-au-lait spots, generalized cutaneous neurofibromata, skeletal deformities, and somatic and endocrine abnormalities. It is an autosomal dominant, hereditary disorder found in approximately 1:2500 to 3300 births. There are many manifestations of this disease in the head and neck region of interest to the otolaryngologist. Case reports of three patients with multiple ENT involvements are detailed. A review of the literature is presented with a brief discussion of diagnosis and treatment. The most common intracranial tumor in the adult is the acoustic neuroma, usually bilateral, while in the child it is the astrocytoma. A defect in the sphenoid bone is common and may produce temporal lobe herniation into the orbit causing pulsatile exophthalmos. Involvement of the facial bones usually causes radiolucent defects secondary to neurofibromata within nerve pathways, and a variety of asymmetrical changes, especially within the mandible. "Elephantiasis" of the face is a hypertrophy of the soft tissues overlying a neurofibroma, often quite extensive and disfiguring. Laryngeal and neck involvement may compromise the airway and early and repeated surgical intervention is required. The over-all malignancy rate approaches 30%, indicating that the patient with VRD may be predisposed to developing a malignancy. There appears to be an increased surgical risk in these patients, with some demonstrating abnormal responses to neuromuscular blockade.
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PMID:E.N.T. manifestations of Von Recklinghausen's disease. 10 Jun 61

We report a case of Lennox-Gastaut-type epilepsy that was followed for 3 years. The patient showed typical EEG findings and later a parietotemporal astrocytoma (type II) on the left. Removal of the tumor was followed by recovery of the child and disappearance of EEG epileptic elements.
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PMID:A case of Lennox-Gastaut syndrome successfully treated by removal of a parietotemporal astrocytoma. 11 78

Murine sarcoma virus, Moloney strain, was inoculated intracerebrally into 75 Spraque-Dawley rats within 24 hours after birth. Of 48 rats examined histologically within 35 days after virus inoculation, most developed granulomatous lesions in the meninges or in the cortex and in the glial nodules of the subependymal region, or in all these regions. The granulomatous lesions first appeared 8 days after virus inoculation and reached a peak about 30 days after virus inoculation. Thereafter, the lesions healed gradually to scars and disappeared. Of 27 rats that survived beyond 35 days, 10 developed brain tumors at or near the sites of cortical granulomatous lesions and subependymal glial nodules. The interval from virus inoculation to death of tumor-bearing rats was between 40 to 115 days, averaging 84 days. The predilection sites were in the subependymal region and hippocampal cerebral cortex. Three brain tumors were cultured using monolayer and rotation culture techniques. These cultured tumor cells showed morphological features very similar to those of the original tumor cells. THe tumor was classified morphologically into the astrocytoma group by light and electron microscopy and by cytological characteristics of tumor cells in tissue culture.
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PMID:The pathology of brain tumors induced by murine sarcoma virus, Moloney strain. 13 51

Three types of tumor (supratentorial astrocytoma, medulloblastoma, and craniopharyngioma), each requiring a fundamentally different therapeutic approach, will be used to illustrate the principles and practice of combined treatment in this field. The role of radiotherapy and ways of enhancing the effect of irradiation will be considered. Attention will be given to adjuvant chemotherapy and to multiple drug regimes. Reference will be made to an early effort at immunotherapy following the initial reduction of tumor cell load by surgery and irradiation.
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PMID:Combined modality therapy for intracranial tumors. 16 49

The various stages of divergent neuroepithelial differentiation were studied in the solid transplants of a transplantable mouse testicular teratoma (OTT-6050) maintained in both ascitic and solid forms. They included: a) areas of undifferentiated medullary epithelium corresponding to the rare human medulloepithelioma; b) areas of neuroblastic differentiation corresponding to neuroblastoma, with more mature neuronal differentiation corresponding to ganglioneuroma or, when mixed with glial elements, to ganglioglioma; and c) more mature neuroglial areas resembling astrocytoma, oligodendroglioma or ependymoma, as well as more primitive areas corresponding to ependymoblastoma. In tissue culture using collagen-coated coverslips, astrocytic differentiation was found in the outgrowth zone after 15 days, confirmed by immunofluorescence with antibodies to an astroglia-specific protein. In organ culture systems, glial components, including ependymal structures, were preserved in tumor explants, and astrocytic differentiation, as expressed by glial fiber formation, was increased after 4 to 6 weeks in vitro. No neuronal differentiation was demonstrable, however. The neuroepithelial component of this experimental teratoma may provide a model for the study of neoplastic neuroepithelial differentiation.
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PMID:An experimental mouse testicular teratoma as a model for neuroepithelial neoplasia and differentiation. I. Light microscopic and tissue and organ culture observations. 16 76

A biopsy specimen of a cerebellar astrocytoma from a 14-year-old girl was studied by light and electron microscopy. Histologically the tumor showed a mixture of loose and compact areas with numerous Rosenthal fibers. By electron microscopy most tumor cells contained, besides the usual organelles, large amounts of 70 to 100 A thick filaments. Classical Rosenthal fibers were also identified. In addition many cell bodies and processes were sprinkled with fragments of Rosenthal fiber material. Ordered filamentous arrays (so-called Hirano bodies) were seen in a number of tumor astrocytes. They are considered to be a nonspecific arrangement of filament units largely devoid of cytopathologic significance. Other ultrastructural features of some tumor cells were inchoate forms of the granulated bodies of conventional histology, paired cisternal elements of rough endoplasmic reticulum, and honeycomb-like profiles of transversely cut cylindrical units of smooth endoplasmic reticulum. Microtubular bodies were numerous in the endothelial cells of the tumor vessels.
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PMID:Rod-shaped filamentous inclusions and other ultrastructural features in a cerebellar astrocytoma. 17 27

The brains of 396 old albino rats of the breed Wistar-AF/Han-EMD were examined for spontaneous tumors of the CNS and the following tumors were diagnosed: 1 oligodendroglioma, 1 astrocytoma, 1 mixed glioma, 1 pleomorphic glioma, and 19 meningiomas. Thus the CNS tumor rate was 5.8%. In addition 6 micromeningiomas were found. Knowledge of the spontaneous tumor rate including the tumor incidence in the CNS of the animal strains used for these examinations is a necessary condition for the evaluation of the results of cancerogenicity tests. CNS tumors deserve particular attention because during recent years it was found that certain chemical compounds like for instance N-methyl-N-nitrosourea induce organ-specific tumors in the brain of rats. It is recommended, therefore, to always include the central nervous system in the autopsy and histologic examination of animals from cancerogenicity trials. For cerebral autopsy transversal sections through the different cerebral regions and histologic examination of transversal section surfaces of all tumors and suspected tumor areas are suggested.
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PMID:The incidence of spontaneous tumors of the central nervous system of Wistar rats. 17 67


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