Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 235 records · Page 13Linked to original sources

PubMed1993

Gliosis specimens contain clonal cytogenetic abnormalities.

The relevance of sex chromosome aneusomy and trisomy 7 in neoplastic brain tissue is controversial. For better understanding of the relative importance of these anomalies, we made a conventional cytogenetic study of cells from tissue obtained from patients who underwent partial cerebral resection for a seizure disorder. Each specimen exhibited "gliosis," but none contained histologically identifiable tumor cells. Sixty-six specimens were analyzed by routine cytogenetic methods. Nonclonal abnormalities were observed in 11.6% of the cells (86% of cases) analyzed. In 11 cases, however, simple clonal karyotypes were observed. Of these cases, six involved loss of a Y chromosome and three involved loss of an X chromosome. Among the cases with loss of an X chromosome, two exhibited multiple abnormal clones. One of these cases had trisomy 7 as well as trisomy 18, and another had a supernumerary psu dic(15)(q13). The supernumerary chromosome was constitutional. One patient had possible Klinefelter syndrome. An additional case had a clonal del(10)(q23) that may have resulted from a hereditary fragile site. We conclude that although some of the apparently acquired clonal and nonclonal abnormalities may be due to a consistent in vitro artifact, it is probable that they are present in the brain tissue itself. Whatever the cause, caution should be used in interpretating cytogenetic abnormalities observed in brain tumor specimens.

Adolescent↗

PubMed1993

Chordoma cutis: a report of nineteen patients with cutaneous involvement of chordoma.

BACKGROUND: Chordoma, an uncommon tumor originating from remnants of the notochord, with cutaneous involvement has rarely been reported. OBJECTIVE: Our purpose was to document clinical manifestations, histopathologic features, immunohistochemical findings, treatment, and course of chordoma with cutaneous involvement. METHODS: Pathologically proven cases of chordoma were reviewed retrospectively for cutaneous involvement. Detailed clinical data and histopathologic changes were studied. Skin biopsy specimens were stained for immunohistochemical phenotyping. RESULTS: Of 207 cases of chordoma, 19 had skin involvement: as local recurrences or metastasis in 12, as direct extension of primary tumor in 6, and as a result of distant metastasis from sacrococcygeal chordoma in 1. Local recurrences were frequent, but distant metastasis to various organs, including skin, occurred. CONCLUSION: We propose the term chordoma cutis to describe this condition. In seven patients, cutaneous lesions were detected when the diagnosis of primary chordoma was made.

Adult↗

PubMed1993

Management of supratentorial low-grade gliomas.

Low-grade gliomas are a clinically, radiographically, and pathologically diverse group of central nervous system neoplasms. Treatment decisions are based primarily on histologic tumor type and patient age. Pilocytic astrocytomas tend to occur in younger patients, are circumscribed, and amenable to cure with gross total resection. There is no role for the routine use of postoperative radiotherapy in these patients. In contrast, infiltrative tumors, including ordinary (nonpilocytic) astrocytomas, mixed oligoastrocytomas, and oligodendrogliomas occur in middle-aged patients and are generally not curable, even with gross total resection. Postoperative radiotherapy of these infiltrative tumors appears to improve survival, particularly in adults. Several ongoing clinical trials are addressing two issues: Observation vs radiotherapy and low-dose vs high-dose radiotherapy in patients with ordinary astrocytomas, oligoastrocytomas, and mixed oligoastrocytomas.

Adolescent↗

PubMed1993

Oligodendrocyte injury is an early event in lesions of multiple sclerosis.

The ultrastructural features of 11 stereotaxic brain biopsy specimens that demonstrated inflammatory primary demyelination consistent with acute multiple sclerosis were examined. Uniform widening of inner myelin lamellae (biphasic myelinopathy) and degeneration of inner glial loops ("dying-back" oligodendrogliopathy) were early pathologic abnormalities that antedated complete destruction of myelin sheaths. Perivascular inflammatory cells (lymphocytes, macrophages, and occasional plasma cells) were in intimate contact with degenerating myelin sheaths. The response of astrocytes was prominent, even in areas of minimal demyelination. Oligodendrocytes were morphologically preserved in early lesions but proliferated at the periphery of active lesions. Thinly myelinated axons indicative of central nervous system-type remyelination by oligodendrocytes were observed primarily at the edge of plaques. Disturbances of the myelinating function of oligodendrocytes--unaccompanied by death of these cells--may be among the earliest pathologic features in multiple sclerosis.

Adolescent↗

PubMed1993

Chronic inflammatory meningoencephalitis should not be mistaken for Alzheimer's disease.

We describe two patients with a chronic encephalopathy that clinically resembled dementia but that resolved after oral administration of high-dose corticosteroid therapy. Both patients had serologically documented Sjögren's syndrome, a diagnosis that was further supported by biopsy of a salivary gland in one. Neither patient had radiologic evidence of vasculitis of the central nervous system. In one patient, meningeal and brain biopsy specimens showed perivascular inflammatory lymphocytic infiltrates. Chronic inflammatory meningoencephalitis is a treatable cause of chronic encephalopathy that should be clinically distinguished from dementia associated with Alzheimer's disease.

Aged↗

PubMed1993

Aging and the human pituitary gland.

Pituitary glands obtained at autopsy from 41 men (90 to 97 years old) and 45 women (90 to 98 years old) were studied histologically and immunohistochemically to determine the age-related alterations. Pituitaries from patients 30 to 39 years old (48 cases) and 60 to 89 years old (187 cases) were also studied and served as controls. Interstitial, perivascular fibrosis was seen in 88% of the aged adenohypophyses and, although significantly more intense than that in those of the fourth decade of life (P < 0.001), was similar to that noted in those of the seventh to ninth decades. Pituitaries of men were significantly more fibrotic than were those of women (P < 0.05). In proportion to the extent of fibrosis, the number of somatotrophs decreased in the lateral wings, whereas other cell types did not change quantitatively. Small deposits of amyloid and of iron were detected in seven and three cases, respectively. Squamous metaplasia in cells of the pars tuberalis was noted in 29%. The incidence of "basophil invasion" (the presence of corticotrophs in the posterior lobe) was 30%, a figure similar to that in younger controls. Granular cell tumorlets were detected in four aged neurohypophyses (5%), a frequency similar to that in control glands. Pituitary adenomas (two null cell, two lactotroph, and one corticotroph adenomas) were found of three men and two women in the study group. This 9% incidence of adenomas did not differ from that observed in the fourth decade (8%) or seventh decade (10%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

PubMed1993

The effect of a platelet activating factor antagonist (BN 52021) on neurologic outcome and histopathology in a canine model of complete cerebral ischemia.

BACKGROUND: Research has demonstrated that platelet activating factor may modulate, in part, the severity of postischemic neurologic injury. The proposed mechanism involves a platelet activating factor-mediated release of cerebral cellular lipids and free fatty acids, resulting in increased cerebral edema and cell injury. The present study tested the hypothesis that a specific platelet activating factor antagonist, BN 52021, would improve neurologic outcome after 12 min of complete global cerebral ischemia in a canine model. METHODS: Using an established canine model of complete cerebral ischemia, dogs were assigned randomly to receive, in a blinded fashion, either 20 mg/kg BN 52021 intravenously (N = 8) or placebo (N = 7) 5 min before cerebral ischemia. After cerebral ischemia and recovery, neurologic assessment was performed by a blinded observer for 72 h. Immediately thereafter, the brains were harvested and later were evaluated histologically by a neuropathologist blinded to the treatment groups. RESULTS: Dogs were well matched for systemic physiologic variables during all portions of the study. One placebo-treated dog and one BN 52021-treated dog were not included in the statistical analysis because of failure to meet preestablished protocol criteria. BN 52021, when compared to placebo, affected neither neurologic functional recovery nor overall histopathology scores. Regional histopathology was improved in BN 52021-treated dogs in only 1 of 18 brain regions studied (i.e., the parietal cortex). When both treatment groups were combined, there was a significant correlation between neurologic function rank and histopathology rank. CONCLUSIONS: The present data demonstrate that the platelet activating factor antagonist BN 52021, at a dose of 20 mg/kg intravenously given 5 min before cerebral ischemia, did not protect the brain from injury in this canine model of complete global ischemia.

Animals↗

PubMed1993

Differential expression of retinal proteins in a pineal parenchymal tumor.

The pineal gland and retina share histogenetic features that reflect a similar neurosensory/photosensory ontogeny. Pineal parenchymal tumors demonstrate a highly variable and incomplete photosensory differentiation evidenced by specific cytoarchitectural features and the expression of photosensory retinal S-Antigen (S-Ag). Despite these neuro-ontogenetic parallels, pineal parenchymal tumors have not been well studied for the neuroretinal phenotypes that accompany normal neuroretinal development. The investigation of photoreceptor gene expression may provide an important insight into the histogenesis of pineal parenchymal neoplasms. In this study, a pineal parenchymal tumor of the "mixed pineoblastoma/pineocytoma" type was examined for the expression of several photoreceptor, glial and neuronal proteins including: interphotoreceptor retinoid-binding protein (IRBP), rod opsin, cone opsin, S-Ag and cellular retinaldehyde-binding protein (CRA1BP). The detection of IRBP and its mRNA, the earliest photoreceptor-associated protein expressed during retinal development, corroborated the rudimentary photosensory differentiation of this tumor which had limited cytoarchitectural evidence for pineal differentiation. The analysis of IRBP expression may facilitate the diagnostic recognition of primitive pineal neoplasms and further define the neuroretinal differentiation which occurs in pineal parenchymal tumors.

Adolescent↗

PubMed1993

The new WHO classification of brain tumours.

The new edition of the World Health Organization (WHO) book on 'Histological Typing of Tumours of the Central Nervous System' reflects the progress in brain tumour classification which has been achieved since publication of the first edition in 1979. Several new tumour entities have been added, including the pleomorphic xanthoastrocytoma, central neurocytoma, the infantile desmoplastic astrocytoma/ganglioglioma, and the dysembryoplastic neuroepithelial tumour. The list of histological variants has also been expanded. In line with recent morphological and molecular data on glioma progression, the glioblastoma is now grouped together with astrocytic tumours. The classification of childhood tumours has been largely retained, the diagnosis primitive neuroectodermal tumour (PNET) only being recommended as a generic term for cerebellar medulloblastomas and neoplasms that are histologically indistinguishable from medulloblastoma but located in the CNS at sites other than the cerebellum. The WHO grading scheme was revised and adapted to new entities but its use, as before, remains optional.

Brain Neoplasms↗

PubMed1993

Phase III comparative evaluation of PCNU and carmustine combined with radiation therapy for high-grade glioma.

PURPOSE: We performed a randomized trial to compare survival distributions and toxicity of radiation therapy (RT) and PCNU with those of RT and carmustine (BCNU) in patients with malignant glioma. PATIENTS AND METHODS: A total of 346 patients with histologically verified supratentorial grade 3 and grade 4 astrocytoma were studied. After surgery, patients were randomly assigned to receive RT 60 Gy in 30 fractions and either PCNU 100 mg/m2 or BCNU 200 mg/m2 every 7 weeks for 1 year and every 10 weeks for the second year. RT and chemotherapy were started within 72 hours of randomization and usually on the same day. Of 334 assessable patients, 72% had partial or radical resection and 71% had grade 4 tumors. Median age was 59 years, and 85% had performance scores of 0 to 2 (Eastern Cooperative Oncology Group [ECOG]). The follow-up duration of 51 living patients ranged from 10.3 to 63.2 months, with a median of 36.2 months. RESULTS: The median survival duration in each group was 47 weeks, and median time to progression was 28 weeks. PCNU produced significantly more leukopenia and thrombocytopenia, whereas BCNU produced significantly more nausea, vomiting, and irritation. CONCLUSION: PCNU has no therapeutic advantage at this dose and schedule and does not warrant further study as a single agent for patients with high-grade glioma.

Adult↗

PubMed1993

Congenital gigantism due to growth hormone-releasing hormone excess and pituitary hyperplasia with adenomatous transformation.

The cause of gigantism in most patients is a GH-secreting pituitary tumor. In this report, a case of congenital gigantism due to probable central hypersection of GH-releasing hormone (GHRH) is described. Normal at birth (4.4 kg; 53 cm), our 7-yr-old male patient grew progressively thereafter to attain a height of 182 cm and a weight of 99.4 kg at the time of our evaluation. The markedly increased baseline plasma levels of GH (730 micrograms/L) did not suppress during a standard 3-h oral glucose tolerance test, but did increase 54% after iv infusion of GHRH. Baseline plasma levels of insulin-like growth factor-I, PRL, and immunoreactive GHRH were also markedly increased. Computed imaging of the head showed a large, partially cystic sellar and suprasellar mass. Extensive imaging studies did not localize a potential source of GHRH. Preoperative treatment with octreotide and bromocriptine for 4 months resulted in a 25% reduction of suprasellar tissue mass. The pituitary tissue removed at transsphenoidal and transfrontal operations showed massive somatotroph, lactotroph, and mammosomatotroph hyperplasia. Areas of GH- and PRL-secreting cell adenomatous transformation were also evident. No histological or immunohistochemical evidence of a pituitary source of GHRH was found. The peripheral plasma immunoreactive GHRH concentration remained unaffected by pharmacological and surgical interventions. We suspect that a congenital hypothalamic regulatory defect may be responsible for the GHRH excess in this case.

Adenoma↗

PubMed1993

Symptomatic intradural adrenal adenoma of the spinal nerve root: report of two cases.

The second and third cases of an adrenal adenoma involving the intraspinal space, a rare location for a lesion that occurs rather commonly at a variety of extraneural sites, are reported. The first patient, a 16-year-old girl with a 3-month history of radicular pain, was found to have an intradural, extramedullary mass arising on a spinal nerve root. Its resection resulted in cure. The second patient, a 63-year-old woman with a 10-month history of low back pain with radiation to both lower extremities, had a similar mass arising from one of the nerve roots of the cauda equina. In both cases, ultrastructural examination of these demarcated, oncocytic, lipid-rich lesions demonstrated abundant smooth endoplasmic reticulum and mitochondria with tubular cristae. The presence of steroidogenic enzymes was noted on immunohistochemical examination. The literature is reviewed, as is the differential diagnosis of these rare lesions.

Adenoma↗

PubMed1993

Simultaneous presentation of symptomatic subependymomas in siblings: case reports and review.

Two young adult siblings independently developed similar neurological complaints that included headaches, photophobia, nausea, and intermittent lancinating facial pains. Magnetic resonance imaging revealed fourth ventricular lesions that required surgery in both patients. A pathological review revealed subependymomas with virtually identical histological features. The clinical features and common pathological findings of both patients suggest that familial subependymomas may have a maldevelopmental origin with genetic implications.

Adult↗

PubMed1993

A retrospective analysis of pituitary apoplexy.

Thirty-seven patients with pituitary apoplexy were analyzed with an emphasis on clinical presentation and visual outcome. Their mean age was 56.6 years, with a male to female ratio of 2:1. Presenting symptoms included headache (95%), vomiting (69%), ocular paresis (78%), and reduction in visual fields (64%) or acuities (52%). Computed tomographic scanning correctly identified pituitary hemorrhage in only 46% of those scanned. Thirty-six patients underwent transsphenoidal decompression. By immunostaining criteria, null-cell adenomas were the most frequent tumor type (50%). Long-term steroid or thyroid hormone replacement therapy was necessary in 82% and 89% of patients, respectively. Long-term desmopressin therapy was required in 11%, and 64% of the male patients required testosterone replacement therapy. Surgery resulted in improvement in visual acuity deficits in 88%, visual field deficits in 95%, and ocular paresis in 100%. Analysis of the degree of improvement in preoperative visual deficits with the timing of the surgery demonstrated that those who underwent surgery within a week of apoplexy had significant recovery in their visual acuities. In the stable, conscious patient with residual vision in each eye, surgical decompression should be performed as soon as possible, because delays beyond 1 week may retard the return of visual function.

Adenoma↗

PubMed1993

Cerebral phaeohyphomycosis.

A 14-year-old girl with a rare form of fungal brain abscess involving the dura and brain parenchyma is reported. No portal of entry of the infection was found. Histological findings and fungal culture both indicated that the causative agent was Xylohypha bantiana, an uncommon dematiaceous fungus. A review of the literature suggests that this infection, which affects primarily young male patients, exhibits distinct neurotropism. Despite therapy, the prognosis is generally poor.

Adolescent↗

PubMed1993

Colloid cyst of the third ventricle. A comparative immunohistochemical study of neuraxis cysts and choroid plexus epithelium.

In an effort to shed light upon the nature of the colloid cyst, the immunohistochemical properties of 21 examples of this lesion were compared with those of other neuraxial cysts and choroid plexus epithelium. The neuraxial cysts included the following: eight Rathke's cleft cysts, 25 pituitaries containing follicular cysts of the pars intermedia, and four enterogenous cysts. Fifteen examples of normal choroid plexus and 12 choroid plexus papillomas were studied as well. These lesions were examined for localization of the following antigens: cytokeratins, epithelial membrane antigen, secretory component, carcinoembryonic antigen, prealbumin, vimentin, glial fibrillary acidic protein (GFAP), S-100 protein, neuron-specific enolase, 68-kD neurofilament protein, chromogranin, serotonin, and lysozyme, and with Leu-7 monoclonal antibodies. Five colloid cysts were immunostained with monoclonal antibodies that were specific for Clara-cell antigens and surfactant, respectively. Sugar moieties were localized using Ulex europaeus I, and Ricinus communis agglutinin I lectins. All Rathke's cleft cysts and follicular cysts of the pars intermedia as well as three selected colloid cysts were examined for pituitary hormones. The epithelial cells of colloid and enterogenous cysts, as well as those lining follicular and Rathke's cleft cyst, showed uniformly strong reactivity for cytokeratins, epithelial membrane antigen, secretory component, and vimentin, and bound Ulex europaeus lectin. Occasional cells in colloid cysts were positive for Clara cell-specific antigens. Reaction for carcinoembryonic antigen was present on the apical surface of scattered cells of colloid, follicular, and Rathke's cleft cysts. Many cells of follicles in the pars intermedia as well as individual cells of five Rathke's cleft cysts were also immunoreactive for chromogranin, S-100 protein, GFAP, and pituitary hormones. Colloid and enterogenous cysts were negative for prealbumin, S-100 protein, GFAP, and neuron-specific enolase; in all but a few instances, they failed to bind Ricinus communis agglutinin. In contrast, normal choroid plexus and choroid plexus papillomas were positive for prealbumin, S-100 protein, neuron-specific enolase, cytokeratin, vimentin, and Ricinus communis agglutinin receptors; they lacked Ulex europaeus lectin, 56/66-kD cytokeratins, and epithelial membrane antigen. Unlike normal choroid plexus, choroid plexus papillomas were often GFAP-positive. All tissues studied were nonreactive for lysosome, serotonin, and neurofilament, and with Leu-7 antibodies. This study indicates that the immunophenotype of epithelium lining colloid cysts is similar to that of other cysts showing endodermal or ectodermal differentiation and to respiratory tract mucosa. Epithelium of colloid cysts is immunohistochemically different from that of normal or neoplastic choroid plexus. These findings indicate an endodermal rather than neuroepithelial nature for colloid cysts.

Brain Diseases↗

PubMed1993

Intracranial chordomas: a clinicopathological and prognostic study of 51 cases.

Fifty-one patients with intracranial chordomas who were surgically treated between 1960 and 1984 were studied. Median patient age was 46 years, and 73% presented with diplopia or headache. Nineteen tumors were classified as the "chondroid" type. The extent of surgical removal was a biopsy in 11 patients and subtotal removal or greater in 40. Thirty-nine patients received postoperative radiation therapy. At the time of analysis, 17 patients were alive, and the estimated 5- and 10-year survival rates were 51% and 35%, respectively, for the group of 51 patients. Univariate analysis showed that: 1) patients undergoing resection lived longer (the 5-year survival rate was 36% for the 11 biopsy patients compared with 55% for the 40 patients who had resection; 2) patients who underwent postoperative radiotherapy tended to have longer disease-free survival times; and 3) overall and disease-free survival data were the same for patients with chondroid tumors and those with typical chordomas. Multivariate analysis showed that: 1) age was the factor most strongly associated with longer overall and disease-free survival; 2) diplopia was associated with longer survival; and 3) tumoral mitotic activity tended to be associated with shorter disease-free survival. One tumor metastasized to the cervical cord, and two tumors underwent anaplastic transformation. These data suggest that the prognosis in patients with chordomas is unfavorable, young age is the single factor most strongly associated with longer survival, surgical resection is beneficial, and postoperative radiotherapy may prolong disease-free survival.

Adult↗

PubMed1993

Results of surgical treatment for growth hormone-secreting pituitary adenomas.

The results of surgical therapy for acromegaly were reviewed in a series of 175 patients treated between 1972 and 1983. Patients with prior surgery or radiation therapy were excluded from the study. Postoperative radiation therapy was given to 54 patients. The criterion of achieving a postoperative basal or glucose-suppressed growth hormone level of 2 ng/ml or less was used to indicate remission. Utilizing the most recently available growth hormone determinations, 90 (51.7%) of 174 patients were in remission. The actuarial probability of remission at 1 and 5 years after surgery was 48.8% and 62.7%, respectively. Tumor size and the preoperative basal growth hormone level were correlated with outcome. Surgical excision of a pituitary adenoma is the most effective therapy currently available for acromegaly.

Adenoma↗