Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twelve cases of a distinctive form of supratentorial astrocytoma occurring in young subjects (ages 7 to 25) are reported. The tumors were superficial and involved the leptomeninges extensively. The tumor cells display marked pleomorphism, including bizarre giant cells and a number of mitotic figures, but no necrosis. Many contain large amounts of lipid in their cytoplasm and are surrounded by reticulin fibers, thus simulating a mesenchymal tumor. For these reasons, some examples of this tumor have been previously interpreted to represent meningocerebral fibrous xanthomas. Immunoperoxidase technique performed in nine of the twelve cases has, however, established the presence of glial fibrillary acidic protein in the tumor cells, which are therefore considered to be astrocytic. By electron microscopy many tumor cells are surrounded by basal laminae, accounting for the abundant reticulin network demonstrable in silver preparations. Since subpial astrocytes are known to be partly covered by a basal lamina, it is likely that they are the cells of origin for this neoplasm. In contrast to its pleomorphic cytology, the biological behavior of this tumor appears to be relatively favorable, and long survival times (up to 25 years) have been recorded in some cases. (These tumors are distinct from intracranial fibrous xanthomas of mesenchymal derivation. Cells of the latter are negative on GFAP stain.)
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PMID:Pleomorphic xanthoastrocytoma: a distinctive meningocerebral glioma of young subjects with relatively favorable prognosis. A study of 12 cases. 49 51

Total lactic dehydrogenase (LDH) levels and LDH isozyme patterns were measured in homogenates of 12 autochthonous ethylnitrosourea-induced rat gliomas and 5 cloned rat astrocytoma cell lines maintained in culture and transplanted to brain or flank sites in syngeneic hosts. The total LDH values in the autochthonous gliomas did not differ appreciably from normal brain controls, but the proportions of the cathodal isozymes, LDH4 and LDH5, were increased to a degree similar to that reported by others in spontaneous human malignant astrocytic gliomas. The cloned astrocytoma lines, both in vitro and in transplants at intracerebral or subcutaneous sites, commonly demonstrated elevated total LDH values and, without exception, showed a preponderance of isozymes, LDH4 and LDH5, that was distinctly more marked than in autochthonous tumors. Especially in cultured and transplanted rat gliomas, these findings suggest that astrocytic tumor cells maintain energy supplies by utilizing anaerobic glycolysis in relatively hypoxic environments. These data further underscore the need to develop laboratory brain tumor models for use in therapy trials that not only retain the convenience and predictability of transplantable gliomas but also approximate closely the metabolic properties of human spontaneous gliomas.
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PMID:Lactic dehydrogenase in ethylnitrosourea-induced rat gliomas. Total lactic dehydrogenase activity and isozymes in autochthonous gliomas and cloned transplantable astrocytomas. 51 89

In order to establish the standard of administration of ACNU against brain tumors, pharmacokinetic analysis of ACNU in tumor tissue, cystic fluid, cerebrospinal fluid and blood was performed. The sample specimens were obtained sequentially after intravenous administration of 1--2 mg/kg/BW of ACNU and quantitatively analysed by high-performance liquid chromatography in 3 cases of glioblastoma and each one case of astrocytoma, meningioma and brain metastasis. Concentrations of ACNU in blood was calculated by two compartment open model and those in cystic fluid was calculated by one compartment model using BMDP-3R program. The half-time in blood was 2.6--4.1 min, and its distribution was very fast. The penetration of ACNU into the tumor tissue was sufficient, because the central compartment was 23% and the tissue compartment was 77%. The transmission rate constant into the cyst was 1.8 and the elimination rate constant was 0.96. The maximum concentration in the cystic fluid 42 min after intravenous injection of 2 mg/kg/BW of ACNU was 0.27--0. 35 mg/dl. In conclusion, 3--4 mg/kg/BW of ACNU should be injected intravenously at one time.
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PMID:[Pharmacokinetic analysis of ACNU in brain tumors (author's transl)]. 52 72

Early clinical manifestations and radiologic features of tuberous sclerosis were studied in 18 consecutive patients encountered in the past two years, including two patients harboring an associated intraventricular tumor (giant-cell astrocytoma). Depigmented naevi rather than adenoma sebaceum, infantile spasms and intracranial calcifications were the cardinal early features in this present series, and CT scanning proved to be the single most useful diagnostic technique in the early detection of intracranial calcifications and therefore for the early diagnosis of this disorder. CT scanning was also useful in detecting the intraventricular tumors in the early stage before they became clinically manifest.
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PMID:Tuberous sclerosis: early neurologic manifestations and CT features in 18 patients. 55 37

This is a report of the neuro-ophthalmologic and neuropathologic findings in a patient with a recurrence of a cerebellar astrocytoma after 48 years. Dr. Harvey Cushing performed the initial operation at the Peter Bent Brigham Hospital in 1928. This patient was included in his classic review: "Experiences with the Cerebellar Astrocytomas--A critical review of seventy-six cases." The extensive documentation of the original tumor by Cushing, the unusually long period of 48 years for the recurrence of the tumor, and the opportunity to examine the patient and postmortem brain specimen in detail make this a unique case report.
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PMID:Neuro-ophthalmologic signs in a recurrent cerebellar astrocytoma after 48 years. 55 30

Quantitation of the concentration of immunoproteins in serum, and cystic fluids from six patients (three with cerebral astrocytoma and three with cerebellar hemangioblastoma) has been determined. The values for total protein, albumin, immunoproteins IgG, IgA, and IgM, and C3C (complement) in cyst fluid more closely correspond to serum than to cerebrospinal fluid values. Values for cyst fluid, cerebrospinal fluid, and serum were determined using albumin ratios in order to compare relative differences between fluids from these three compartments. Our data suggests that: 1) the major protein content of brain tumor cyst fluid is consequential to a transudative process from serum, and 2) that immunoglobulins IgG and IgA are present in higher concentrations in human brain tumor cyst fluids in comparison to IgM concentrations. These studies further question the concept of the brain as an "immunological privileged site", and may be of direct relevance to the investigation of the use of immunotherapeutic modalities as an adjunct after surgical tumor removal.
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PMID:Immunoproteins in human brain tumor cyst fluids. 55 78

Three sisters died of astrocytoma, and the microscopic appearance of the tumor was the same in all three. This finding supports either genetic or environmental influences in the occurrence of brain tumors.
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PMID:Astrocytoma in three sisters. 56 99

The effect of infusions of 14,15-dihydro-14beta-hydroxy-(3alpha, 16alpha)-eburamenine-14-carbonic acid methylester (vincamine; Vincopront) on cerebral blood flow (CBF) was investigated by the xenon clearance method. In 12 patients receiving 30 mg vincamine within 35--40 min no significant changes in hemispheric or regional CBF were observed. 14 patients received 40 mg vincamine within 35--40 min: in this group hemispheric CBF was significantly increased (p less than 0.01) when compared to the spontaneous changes observed in a control group. The increase was particularly prominent in poorly supplied brain regions. This effect was proved statistically by regression analysis. In a patient with astrocytoma the tumor-hyperperfusion was diminished by vincamine while the flow to the surrounding brain improved. The results indicate the dependency of the vincamine effect on the rate of application and thereby on the plasma concentration of the drug.
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PMID:[The effect of vincamine on cerebral blood flow as a function of application rate (author's transl)]. 57 55

A 49-year-old woman with a two-year history of headaches that became progressively more frequent was found on computerized tomographic scan to have a dense, enhancing right frontoparietal mass. The tumor mimicked a meningioma in that it indented the inner table of the skull, was well demarcated from the underlying brain, and microscopically lacked the fibrillated cell processes and background that characterize astrocytomas. The 80- to 100-A cytofilaments were sparse and seen in few cells. It was only by the immunoperoxidase stain for glial acidic protein that the diagnosis of an extra-axial leptomeningeal astrocytoma was established.
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PMID:Extracerebral leptomeningeal astrocytoma mimicking a meningioma. 58 26

31 cases with tumours in chiasm and hypothalamus are presented. 21 cases had glioma of chiasma (the tumor continued along one or both optic nerves), six cases had craniopharyngioma and four cases had astrocytoma in the hypothalamus. All of these tumours represent 19% of intracranial tumours observed in our service over a period of eleven years. Russell's syndrome was usually seen in cases of gliomas of chiasm. Visual alterations were observed in a high average of patients with any type of the tumours. Skull in lateral view was a positive proof in all the three types of tumours showing "omega" sella turcica in gliomas of chiasm, supra or retro-sellar calcifications in croniopharyngiomas and large sella turcica in astrocytomas of the hypophalamus. Neumoencephalography and angiography were very positives proofs in all types of tumours. Gammagraphy was specially possitive in gliomas of chiasm. Computed axial tomography is very useful in all types of tumour, but our experience is still limited in comparison with other methods. Most effective treatment for gliomas of the chiasm was radiotherapy with shunt in cases with hydrocephalus and total or partial extirpation in astrocytomas of the hypothalamus and in craniopharyngiomas. Survival rate among patients with these types of tumour is high but presence of visual and endocrinological secuelae is very high too.
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PMID:[Tumours of chiasmatic and hypothalamic regions in children (author's transl)]. 60 5


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