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B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 199 records · Page 11Linked to original sources
PubMed1995

Hemangioblastoma of the optic nerve: case report.

An optic nerve hemangioblastoma arising in the optic nerve of a patient with von Hippel-Lindau syndrome is reported. This represents the 10th published example of a hemangioblastoma arising at this site, the second description of the magnetic resonance imaging features of a hemangioblastoma at this location, and the second patient from whom an optic nerve hemangioblastoma has been removed with the goal of preserving the optic nerve as well as vision. A majority of these optic nerve hemangioblastomas have arisen in patients with von Hippel-Lindau syndrome. All patients experienced progressive loss of vision either to blindness or surgical intervention, although a vast majority of the lesions were sharply demarcated from the adjacent nerve and, thus, potentially resectable. Optic nerve hemangioblastomas are a rare cause of blindness but potentially preventable when treated with a conservative surgical approach aided by neuroimaging guidance. The recognition of discordance between the degree of vision loss and the extent or progression of a retinal hemangioblastoma may be an important clue to diagnosis in the patient with von Hippel-Lindau syndrome.

Adult↗
PubMed1995

Acoustic schwannoma and pregnancy: a DNA flow cytometric, steroid hormone receptor, and proliferation marker study.

For a long time, it has been speculated that pregnancy stimulates the growth of acoustic schwannomas. To test this hypothesis, immunohistochemical stains for estrogen receptor, progesterone receptor, and proliferating cell nuclear antigen (PCNA) were performed. Flow cytometric studies for DNA ploidy and S-phase fraction determinations were also performed. The study subjects included 6 female patients with unilateral acoustic tumors; at the time of tumor removal, 1 woman was pregnant and the other 5 women were 2 to 10 months postpartum. The age-sex-matched control group consisted of 6 men and 12 nonpregnant women, all with acoustic schwannomas similar in size to those of the study group. The study found no statistically significant association between the presence or quantity of estrogen or progesterone receptors and pregnancy, DNA ploidy, proliferation indices, or clinical data. Based on PCNA indices, large tumors tended to be less "biologically active" than small lesions (P < .01). The authors concluded that pregnancy does not significantly stimulate the cellular growth of acoustic schwannomas.

Biomarkers↗
PubMed1995

Phase II evaluation of recombinant interferon alpha and BCNU in recurrent glioma.

The goal of this study was to determine the antitumor activity and toxicity of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) plus recombinant interferon-alpha (IFN-alpha) in patients with recurrent glioma. As single agents, both BCNU and IFN-alpha can cause tumor regression in patients with recurrent glioma. In vitro studies suggest synergy between the two agents. Thirty-five patients in whom computerized tomography (CT) or magnetic resonance (MR) evidence was obtained of progressive astrocytoma, oligoastrocytoma, or oligodendroglioma received recombinant IFN-alpha 2a (12 x 10(6) U/m2 intramuscularly) on Days 1 through 3 and BCNU (150 mg/m2 intravenously) on Day 3 of each 6-week cycle. All patients had tumor progression despite radiation therapy and had received no prior chemotherapy. Response was assessed by CT or MR evidence and by neurological examination while the patients were on a regimen of stable or decreasing doses of corticosteroids. All patients could be evaluated for response and toxicity. Twenty-nine percent of the patients demonstrated objective tumor regression; 37% remained stable for more than 6 months and 25% were stable for less than 6 months. The median duration of response to IFN-alpha and BCNU was 9.9 months and the median survival for all patients was 13.3 months. Toxicity consisted primarily of moderate myelosuppression, venous irritation, vomiting, flulike symptoms, and transient reversible exacerbation of underlying neurological symptoms. The use of BCNU plus IFN-alpha is a safe, active regimen in the treatment of patients with recurrent glioma who have failed to respond to prior radiation therapy. The contribution of IFN to the antitumor activity observed in this study compared with that previously described with BCNU alone cannot be assessed from this trial.

Adult↗
PubMed1995

Radiation necrosis or glioma recurrence: is computer-assisted stereotactic biopsy useful?

Fifty-one patients with supratentorial glioma treated with external beam radiotherapy (median dose 59.5 Gy) who then demonstrated clinical or radiographic evidence of disease progression underwent stereotactic biopsy to differentiate tumor recurrence from radiation necrosis. The original tumor histological type was diffuse or fibrillary astrocytoma in 21 patients (41%), oligodendroglioma in 13 (26%), and oligoastrocytoma in 17 (33%); 40 tumors (78%) were low-grade (Kernohan Grade 1 or 2). The median time to suspected disease progression was 28 months. Stereotactic biopsy showed tumor recurrence in 30 patients (59%), radiation necrosis in three (6%), and a mixture of both in 17 (33%); one patient (2%) had a parenchymal radiation-induced chondroblastic osteosarcoma. The tumor type at stereotactic biopsy was similar to the original tumor type and was astrocytoma in 24 patients (47%), oligodendroglioma in eight (16%), oligoastrocytoma in 16 (31%), unclassifiable in two (4%), and chondroblastic osteosarcoma in one patient (2%). At biopsy, however, only 19 tumors (37%) were low grade (Kernohan Grade 1 or 2). Subsequent surgery confirmed the stereotactic biopsy histological findings in eight patients. Follow-up examination showed 14 patients alive with a median survival of 1 year for the entire group. Median survival times after biopsy were 0.83 year for patients with tumor recurrence and 1.86 years for patients with both tumor recurrence and radionecrosis; these findings were significantly different (p = 0.008, log-rank test). No patient with radiation necrosis alone died. Other factors associated with reduced survival were a high proportion of residual tumor (p = 0.024), a low proportion of radionecrosis (p < 0.001), and a Kernohan Grade of 3 or 4 (p = 0.005). In conclusion, in patients with previously irradiated supratentorial gliomas in whom radionecrosis or tumor recurrence was clinically or radiographically suspected, results of stereotactic biopsy could be used to differentiate tumor recurrence, radiation necrosis, a mixture of both lesions, or radiation-induced neoplasm. In addition, biopsy results could predict survival rates.

Adult↗
PubMed1995

Carcinoembryonic antigen production associated with an osteolytic meningioma. Case report.

An elevated serum carcinoembryonic antigen (CEA) without evidence of neoplasia was noted in an 84-year-old woman. She subsequently developed a lytic skull lesion, which at surgery proved to be an atypical meningioma. Immunohistochemical analysis demonstrated that this tumor was producing CEA. This aggressive meningioma required two further resections and adjuvant radiotherapy in the following 18 months. Serum elevation of CEA has been reported only twice in association with meningiomas; both of those tumors were of the secretory subtype.

Aged↗
PubMed1995

Primary intracerebral malignant lymphoma: a clinicopathological study of 89 patients.

The authors report on a clinicopathological study of 89 surgical patients with histologically proven primary parenchymal brain lymphoma, all diagnosed between January 1975 and December 1990. The cohort included 60 men and 29 women whose median age at diagnosis was 60 years (range 14 to 84 years). The duration of symptoms was less than 8 weeks in 48% of the patients. Symptom groups included focal neurological deficit (73%), neuropsychiatric symptoms (28%), seizures (9%), and increased intracranial pressure (3%). A total of 132 tumors were seen in 89 patients: the most common sites were frontal (32 patients), temporoparietal (31 patients), and basal ganglia (17 patients); multiple lesions were reported in 23 patients. No patient had antecedent of human immunodeficiency virus positivity or acquired immunodeficiency syndrome. A family history of cancer was present in 33% of the patients, three-quarters of whom were first-degree relatives. Histological subtypes (National Cancer Institute Working Formulation) included 64 large cell (72%) and 13 immunoblastic (15%) tumors. Phenotype was determined in 66 patients: 63 were B-cell type and three were T-cell type. Surgical resection was performed in 47% of the cases, with the remainder undergoing biopsy only. All but six patients received radiation therapy. Thirty-one patients received chemotherapy, whereas 46 patients did not; data on the remaining 12 patients were unavailable. The end point of the study was death from any cause. At the time of last contact, 69 of the patients (78%) had died; the median survival time for this study group was 20.9 months. On univariate analysis, prognostic factors significantly associated with survival included age at diagnosis, family history of cancer, and focal neurological deficit. Multivariate analysis revealed four unfavorable prognostic factors: age greater than or equal to 60 years, history of cancer in first-degree relatives, focal deficit, and ependymal contact. After adjustment for these variables, clinical syndrome, size and number of lesions, extent of surgery, histological cell type, radiation dose, and use of chemotherapy were not significantly associated with survival.

Adolescent↗
PubMed1995

Papillary craniopharyngioma: a clinicopathological study of 48 cases.

Two distinct clinicopathological variants of craniopharyngioma exist: the classic adamantinomatous type and a recently described papillary form that predominates in adults and reportedly behaves in a less aggressive manner. The present study describes the clinicopathological features of 48 patients with papillary craniopharyngioma treated at the Mayo Clinic between 1910 and 1994. An additional four tumors were found to have histological features of both adamantinomatous and papillary craniopharyngioma. Whereas adamantinomatous tumors typically occur in adolescent patients, the mean age of the 48 patients (23 males and 25 females) with papillary craniopharyngioma was 44.7 years (range 10 to 74 years). Presenting clinical features included visual impairment (84%), headache (68%), and pituitary insufficiency (anterior 42%; posterior 27%). Preoperative computerized tomography (CT) and magnetic resonance (MR) imaging in 17 patients typically revealed a noncalcified, partially cystic mass that enhanced peripherally and contained mural nodules (67%). Many (41%) of the lesions involved or extended into the third ventricle on imaging. At first surgery, gross total tumor removal was achieved in 17 patients (36%) and subtotal resection in 30 patients (64%) in whom tumor resection was attempted. Tumor recurrence was noted in two patients who underwent gross total removal. Tumor-free survival rates of 100% and 78% were obtained in patients who underwent gross total and subtotal resection at initial surgery, respectively. Postoperative radiation therapy was beneficial to patients having undergone a subtotal resection, with an increase in tumor-free survival from 26% to 86%. Aside from well-documented morphological distinctions, papillary craniopharyngiomas differ from adamantinomatous tumors in several important respects. These include the almost exclusive occurrence of papillary tumors in adulthood and their more uniform appearance on both CT and MR imaging. However, a preliminary analysis of our data suggests there are no significant differences between the two lesions with respect to resectability, efficacy of radiation therapy, and overall survival.

Adolescent↗
PubMed1995

Spinal cord astrocytoma: pathological and treatment considerations.

Seventy-nine patients underwent surgery, with or without radiation therapy, for astrocytoma of the spinal cord. There were 43 tumors (54%) classified as pilocytic astrocytoma and 25 (32%) as diffuse fibrillary astrocytoma. Eleven tumors (14%) could not be classified other than as astrocytoma, "type not otherwise specified." The 10-year overall survival rate for all 79 patients was 50% but significantly differed by histological type: 81% for patients with pilocytic astrocytoma compared to 15% for those with diffuse fibrillary astrocytoma. Tumor grade by the Kernohan, et al., or St. Anne-Mayo methods was also a significant predictor of survival in patients with diffuse fibrillary astrocytoma. The extent of surgical resection (biopsy vs. subtotal resection vs. gross total resection) did not significantly impact survival among patients with pilocytic or nonpilocytic astrocytomas of the spinal cord, although there was a trend toward poorer survival in patients undergoing some degree of resection as opposed to biopsy. Postoperative radiation therapy improved survival but did so more for diffuse fibrillary astrocytoma than pilocytic astrocytoma. In this series, histological type was the most significant predictor of survival in patients with astrocytoma of the spinal cord. The survival rate was highest in patients who underwent biopsy followed by postoperative radiation therapy.

Adult↗
PubMed1995

Pilocytic astrocytomas: well-demarcated magnetic resonance appearance despite frequent infiltration histologically.

OBJECTIVE: To determine the magnetic resonance imaging (MRI) characteristics of pilocytic astrocytomas and to correlate them with the histopathologic findings. MATERIAL AND METHODS: MRI examinations and histopathologic findings in 56 patients with pilocytic astrocytomas were retrospectively reviewed. In 38 patients, findings on MRI were compared with those on computed tomography. RESULTS: The tumors occurred at all levels of the central nervous system, including the spinal cord. The intracranial tumors were periventricular (73%) or periaqueductal (9%). All tumors were typical pilocytic astrocytomas and were grade 1 on the basis of the World Health Organization classification. At operation, they were often circumscribed and cystic. Radiologically, the tumors were well demarcated (96%), had benign morphologic features, and almost always showed enhancement (94%). CONCLUSION: MRI of pilocytic astrocytomas typically demonstrated a relatively large, sharply demarcated periventricular mass with pronounced contrast enhancement but minimal or no associated edema. Often, the tumors were cystic on MRI. Despite the well-demarcated appearance grossly and on MRI, pathologic review showed that many of these tumors (64%) infiltrated the surrounding parenchyma, particularly the white matter.

Adolescent↗
PubMed1995

Nitric oxide synthase in the human pituitary gland.

Nitric oxide (NO) is generated by the NO synthase family of isozymes, which is present in many mammalian cells. The constitutive NO synthase isozymes generate NO, which acts via signal transduction mechanisms in the regulation of many functions including vascular tone and blood pressure, and the inducible isozymes mediate immunological mechanisms by cytotoxic and cytostatic effects. To determine whether NO has a role in anterior pituitary cell function, immunohistochemistry and in situ hybridization analyses were used to study NO synthase expression in normal and neoplastic human pituitary tissues. Brain NO synthase was localized in the anterior pituitary in secretory and in folliculo-stellate cells and in the posterior pituitary. Pituitary adenomas had higher levels of brain NO synthase protein and mRNA compared with normal pituitaries. Endothelial NO synthase was also present in anterior and posterior pituitary cells and in endothelial cells of the pituitary. Immunoblotting studies with brain NO synthase antibodies detected a slowly migrating approximately 155-kd band and more rapidly migrating approximately 90-kd and approximately 60-kd bands. Endothelial NO synthase, but not macrophage NO synthase, was also detected in the pituitary by immunoblotting studies, confirming the immunohistochemical observations. These findings indicate that NO synthase is expressed in normal and neoplastic human pituitary tissues with increased levels of brain NO synthase protein and mRNA in adenomas compared with non-neoplastic pituitary cells and suggest that NO may play a regulatory role in hormone secretion in anterior pituitary cells.

Adenoma↗
PubMed1995

Clear cell meningioma. A clinicopathologic study of a potentially aggressive variant of meningioma.

Since clear cell meningioma has only recently been recognized as a morphologic entity, its pathobiology has not been studied. Fourteen examples occurring in seven females and six males, ages 9 to 82 years (mean 29 years), were examined; one was associated with type 2 neurofibromatosis. Of these cases, seven (50%) were spinal-intradural (six lumbar, one thoracic), three (21%) arose in the posterior fossa (cerebellopontine angle), three (21%) were supratentorial, and one (7%) was centered upon the foramen magnum. In one case (8%), two tumors were considered to be independent primaries. One tumor (8%) appeared to show no dural attachment. Thirteen tumors were subject to complete study. All were composed of sheets of clear, glycogen-rich, polygonal cells forming only a few vague whorls. Hyalinization, both stromal and perivascular, was often extensive. Mitoses were rare in primary tumors. Immunohistochemistry showed vimentin and epithelial membrane antigen staining to be reactive in 100%. Stains for S-100 protein and CAM 5.2 were negative. Progesterone and estrogen receptor staining was observed in 77% and 0%, respectively. Ultrastructural study showed abundant cytoplasmic glycogen, a few cytoplasmic lumina, intermediate filaments, interdigitation of cell membranes, and desmosomal junctions. The means, medians, and ranges of proliferating cell nuclear antigen (PCNA) and MIB-1 antigen labeling indices for nonrecurring and recurring tumors were 10.4%, 8.8%, 0.8-23.4% and 11%, 1.4%, 0.1-50.3%, as compared with 7.4%, 6.7%, 2.9-17.2% and 13.3%, 13.4%, 3.3-25.7%, respectively. Twelve successful DNA ploidy studies showed that 11 tumors (85%) were diploid and one was tetraploid; percentage S-phase determinations varied from 4 to 9% (mean 6.0%). Recurrence was noted in eight patients (61%) (five of whom had multiple recurrences); there was local discontinuous spread in two cases (15%) and widespread cranial to spinal metastasis in one case (8%). Three patients (23%) are dead of disease. In summary, clear cell meningiomas are morphologically unique, show no sex predilection, affect primarily the lumbar region and cerebellopontine angle, and despite their benign appearance, may be inordinately aggressive, particularly intracranial examples. No close association was noted between recurrence or clinical outcome and such factors as mitotic activity, PCNA proliferation indices, percent S-phase determination, or DNA ploidy status. In contrast, MIB-1 proliferation indices were appreciably higher among recurring tumors.

Adolescent↗
PubMed1995

Analysis of the chromogranin A post-translational cleavage product pancreastatin and the prohormone convertases PC2 and PC3 in normal and neoplastic human pituitaries.

Several members of the chromogranin/secretogranin (Cg/Sg) family are post-translationally processed in neuroendocrine cells and tumors to smaller peptides, some of which are biologically active. For example, CgA is processed to pancreastatin, parastatin, and other peptides. We analyzed the distribution of pancreastatin and CgA proteins in normal and neoplastic pituitaries as well as the prohormone convertases PC2 and PC3/1 (PC3), the putative processing enzymes for the Cg/Sg family, in 35 pituitary adenomas and 4 non-neoplastic pituitaries by immunohistochemistry and immunoblotting with highly specific antisera. CgA and CgB mRNAs were also examined. Pancreastatin was present in all subtypes of pituitary tumors, although prolactin-secreting adenomas expressed this peptide less frequently than did other tumor types. CgA protein and CgA mRNA expression were also restricted in prolactin adenomas and in normal prolactin cells, as shown by combined in situ hybridization and immunostaining. The prohormone convertases PC2 and PC3 were present in pituitary tumors and in non-neoplastic pituitaries. Immunoblot analysis and immunostaining showed a principal approximately 69-kd PC3 band and a approximately 68-kd PC2 band. Adrenocorticotrophic hormone-secreting adenomas expressed mainly PC3 as determined by immunoblotting and immunohistochemistry, whereas all other adenoma groups expressed predominantly PC2. These results indicate that the enzymes capable of processing CgA and other members of the Cg/Sg family to peptides with biological activity such as pancreastatin are widely expressed in human pituitary adenomas and in non-neoplastic pituitaries, with adrenocorticotrophic hormone tumors expressing predominantly PC3 and other adenomas expressing mainly PC2. The infrequent expression of CgA protein and pancreastatin peptides in normal and neoplastic prolactin cells suggests a unique role of CgA in these tumors.

Adult↗
PubMed1994

Gangliosides as diagnostic markers of human astrocytomas and primitive neuroectodermal tumors.

BACKGROUND: Limitations of classification schemes for brain tumors based solely on morphology have stimulated searches for molecular markers of nosologic and prognostic value. Gangliosides are logical candidates because there are high concentrations of them in the nervous system, there is evidence of their roles in regulation of growth and differentiation, and data from small series suggest correlations between ganglioside composition and glioma type. METHODS: Ganglioside compositions were determined for 70 primary human brain tumors: 16 low grade astrocytomas (LG), 12 anaplastic astrocytomas (AA), 34 glioblastoma multiformes (GBM), and 8 primitive neuroectodermal tumors (PNET). This method involved identification and quantitation of specific gangliosides using chemical analysis and immunoanalysis. RESULTS: Among all tumor types, histologic grade correlated with a progressive loss of 1b gangliosides (P < 0.0001). GQ1b was higher in LGs than in AAs (P < 0.001). Both GT1b and GD1b were higher in AAs than GBMs (P < 0.01 and 0.05, respectively) and lower in PNETs than in GBMs (P < 0.05). GM3 was higher in PNETs than in any astrocytoma group and higher in GBMs than in either AAs or LGs. There was a significant difference in the content of 3'-LM1 among all groups (P < 0.005), between AAs and GBMs (P < 0.05), and between low grade ordinary and juvenile pilocytic astrocyomas (P < 0.01). The lacto-series ganglioside 3'-isoLM1 was present in all groups except PNET. CONCLUSIONS: These results indicate that patterns of gangliosides could be of considerable value in refining the classification and diagnosis of primary human brain tumors.

Adult↗
PubMed1994

Prognostic factors in gliomas. A multivariate analysis of clinical, pathologic, flow cytometric, cytogenetic, and molecular markers.

BACKGROUND: The ability to divide subsets of patients with glial neoplasms into prognostic groups currently is limited because only a few clinical and pathologic variables are available. The goal of this investigation was to identify biologic factors of potential prognostic value in patients with cerebral gliomas. METHODS: This prospective investigation used clinical, pathologic, flow cytometric, cytogenetic, and molecular genetic variables as potential prognostic factors in 207 patients with newly diagnosed gliomas (153 astrocytic tumors of the fibrillary type, 31 oligodendrogliomas, and 23 pilocytic astrocytomas). Classification and regression tree (CART) analysis was performed as part of the multivariate statistical analysis. RESULTS: The age of the patient and the grade of the tumor were confirmed as strong prognostic factors. Cytogenetic or molecular genetic abnormalities of chromosomes 7 and 10 were associated with poor survival in univariate analysis (P < 0.0001). CART multivariate analysis identified several subsets of patients with different prognoses. In the subset of patients younger than 66.5 years with Grade 4 tumors, the survival time was longer for those with aneuploid tumors than for those with nonaneuploid tumors. In the subset of patients with Grades 1-3 tumors, the survival time was longer for those whose tumors had a %G2M of less than 6.9 than for those whose tumors had a %G2M of 6.9 or greater. CONCLUSION: This investigation provides further evidence that flow cytometry, cytogenetic, and molecular genetic factors that may have prognostic value in patients with gliomas can be identified.

Adult↗
PubMed1994

Mast cell-rich convexity meningioma presenting as chronic subdural hematoma: case report and review of the literature.

A 47-year-old woman with a convexity meningioma presenting as a chronic subdural hematoma is reported. This case is unique in that the symptoms were cyclical and stereotypic. The tumor contained an unusually high number of mast cells. A possible etiologic role of histamine-related vasodilation and tumoral hemorrhage is explored. The relationship between meningioma and subdural hematoma is discussed, and the literature is reviewed.

Brain↗
PubMed1994

Aggressive medulloblastoma with high-level N-myc amplification.

A 27-year-old man was treated for an aggressive cerebellar medulloblastoma that, at operation, exhibited dural invasion. Six months after gross total resection and radiation therapy, a "surgical metastasis" developed in the lower portion of the surgical scar. The tumor grew rapidly down into the right side of his neck. Chemotherapy failed, and he subsequently died. Cytogenetic and molecular genetic studies revealed multiple numeric and structural chromosome abnormalities, including an abnormal chromosome 17p arm, more than 100-fold N-myc amplification, a rearranged c-myc gene, and a 16-base pair deletion involving exon 7 of the p53 gene. We postulate that these genetic features may have contributed to the aggressive behavior of the tumor.

Adult↗