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Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 415 records · Page 23Linked to original sources

Thrombosed arteriovenous malformations of the brain. An important entity in the differential diagnosis of intractable focal seizure disorders.

Thrombosed arteriovenous malformations (AVM's) in patients with no previous history of hemorrhage are uncommon but benign lesions that present with clinical and radiographic findings which are often indistinguishable from those of other mass lesions, particularly low-grade gliomas. The authors report seven cases of thrombosed AVM's presenting as intractable seizure disorders in which the radiographic studies had suggested a low-grade glioma. All seven patients are now seizure-free 2 to 40 months postoperatively. The importance of surgical exploration in the management of such patients is emphasized. A review of 32 cases reported in the literature is presented. The reasons why angiography may fail to demonstrate an AVM, and the possible etiologies for the spontaneous thrombosis of an AVM are discussed.

Adolescent↗

Melanotic neuroectodermal tumor of infancy: a malignant tumor of the femur.

An 18-month-old white girl had a malignant melanotic neuroectodermal tumor of infancy of the left femur. Light microscopic findings of a biopsy specimen of the femoral lesion demonstrated the characteristic histologic features, that is, nests of small cells with hyperchromatic nuclei and scant cytoplasm lying within cleftlike spaces lined by cuboidal, melanin-producing cells. Electron microscopy confirmed both neuroblastic and melanocytic differentiation. Despite radiation and chemotherapy, an extensive pelvic tumor developed, which prompted laparotomy 20 months after the femoral biopsy, The apparently metastatic tumor was largely necrotic, but viable nests of undifferentiated small cells and rare individual melanin-containing cells were identified. The patient died 4 months later, at 3 years of age. This case is of particular importance because it is the first example of this tumor found in a long bone. No similar lesions were seen in 17,000 primary tumors of bone treated and seen in consultation at this institution. Its aggressively malignant clinical course is also unusual; only 6 of the 159 cases of melanotic neuroectodermal tumor of infancy reported to date have expressed malignant behavior.

Female↗

Cerebral angioendotheliomatosis.

Angioendotheliomatosis is a rare, often disseminated proliferation of malignant intravascular cells of presumed endothelial origin. The disease may primarily affect the cerebral vasculature and lead to confusing symptoms and signs that often defy accurate clinical diagnosis.

Adult↗

Primary pulmonary leiomyosarcomas. A light and electron microscopic study.

Fewer than 100 cases of primary leiomyosarcoma of the lung have been reported, few of which have been studied by electron microscopy. We performed clinicopathologic studies, including fine structural analysis, of two such cases. Their ultrastructural features differed in part from those of other smooth-muscle tumors, which may help exclude other malignant pulmonary lesions from the differential diagnosis.

Adult↗

The spectrum of inappropriate pituitary thyrotropin secretion associated with hyperthyroidism.

Two patients with overproduction of thyroid-stimulating hormone (TSH) are described. The first patient, a 25-year-old man with recurrent hyperthyroidism, had a pituitary adenoma and highly elevated levels of TSH. While the patient was receiving 0.3 mg of thyroid daily, and basal TSH level was 161 microM/ml. Despite an increase in the thyroid hormone therapy, serum TSH levels remained elevated. The administration of thyrotropin-releasing hormone (TRH) or dexamethasone resulted in no changes in TSH level. The second patient was an 18-year-old man who had inappropriately elevated levels of TSH 3 months after radioiodine therapy for hyperthyroidism. A gradual increase in thyroid hormone replacement therapy decreased the serum TSH levels from 250 to 14.8 microM/ml. The administration of TRH led to huge increases of TSH. Dexamethasone inhibited basal TSH but not TRH-stimulated TSH levels. The overproduction of TSH was attributed to autonomous, neoplastic secretion in the first case and to partial, selective pituitary thyrotroph resistance to thyroid hormone in the second.

Adenoma↗

Thymic neoplasia in two male siblings.

Thymic tumors are uncommon, and malignant variants of such neoplasms are rare. Hence, the association of two siblings with aggressive tumors of the thymus is not likely to be a coincidence. We report on two brothers with thymic epithelial neoplasms, one being a thymic carcinoma and the other an invasive spindle cell thymoma with associated hypogammaglobulinemia.

Adult↗

Cerebral medulloepithelioma. Report of a case with multiple divergent neuroepithelial differentiation.

A cerebral medulloepithelioma, a rare embryonal multipotential central neuroepithelial neoplasm of childhood, is described, bringing to 16 the total number of cases reported in the literature. It is the first example recorded to date which displayed the entire range of differentiation from embryonal to mature cells, of both glial and neuronal lineage (i.e., primitive medullary epithelium, spongioblasts, astrocytes, oligodendroglia, ependymal cells, neuroblasts, and mature ganglion cells). The significance of this tumor as a paradigm of multipotential divergent neuroepithelial differentiation is discussed.

Adolescent↗

Cerebral metastasis in Hodgkin's disease.

Hematogenous metastases of Hodgkin's disease to the brain in the absence of contiguous bone and/or meningeal involvement are extremely rare. The clinicopathologic features of six published cases are reviewed and an additional patient with multifocal parenchymal metastases reported on.

Adult↗

Meningeal mesenchymal chondrosarcoma: report of 8 cases with review of the literature.

This paper reviews 8 personally examined cases of primary meningeal mesenchymal chondrosarcoma and 4 similar cases previously reported by others. The clinicopathologic features of these extraosseous intracranial and intraspinal examples are similar to those of other extraskeletal mesenchymal chondrosarcomas. The tumor occurred most often in the second and third decades, showed a moderate tendency to local recurrence (5 of 12 cases) and occasionally metastasized to the lungs (1 case). Both intracranial and intraspinal tumors occurred with equal frequency, but the former, probably due to the later onset of symptoms, had the worse prognosis. Microscopically, they are composed of primitive undifferentiated mesenchymal cells and frequently well-defined islands of hyaline cartilage. There is an apparent correlation between the frequency of mitotic figures and the likelihood of recurrence and metastasis. Electron microscopic study of one example revealed morphologic features similar to those previously described by others and supports the conclusion that the neoplastic cells represent primitive precartilaginous mesenchyme displaying focal cartilaginous differentiation.

Adolescent↗

Juvenile neuroaxonal dystrophy: clinical, electrophysiological, and neuropathological features.

We describe 2 brothers with progressive myoclonus epilepsy that began in the second decade and was associated with cerebellar ataxia and intellectual deterioration. Electroencephalographic and cerebral evoked potential studies showed findings associated with myoclonus epilepsy. Neuropathological examination of 1 of the brothers, who died at age 23 years, revealed widespread changes of neuroaxonal dystrophy without pigment deposition in the basal ganglia. We propose the term juvenile neuroaxonal dystrophy (JNAD) to distinguish this condition on clinical grounds from infantile neuroaxonal dystrophy on the one hand, and on clinical and pathological grounds from Hallervorden-Spatz disease on the other hand. JNAD, while exceedinly rare, must be considered in the differential diagnosis of the progressive myoclonus epilepsies.

Adolescent↗

Neuroaxonal dystrophy (Seitelberger's disease) with late onset, protracted course and myoclonic epilepsy.

We present the pathologic findings, including electron microscopy, in one of two affected borthers with severe progressive myoclonus epilepsy, beginning in our patient at the age of 10 and leading to death at age 23. At autopsy there was widespread and marked neuroaxonal dystrophy, severe cerebellar atrophy, and tract degenerations in the gracilis columns and the lateral corticospinal tracts in the spinal cord. There was no increased pigmentation in the globus pallidus or reticular zone of the substantia nigra, on gross or microscopic examination. We regard this case as an example of a juvenile form of neuroaxonal dystrophy (Seitelberger's disease). The absence of pallido-nigral hyperpigmentation distinguishes this disease from Hallervorden-Spatz disease, which we regard as a separate disease entity.

Adult↗

Ewing's sarcoma of the spinal epidural space: report of two cases.

Two new cases of primary extraosseous Ewing's sarcoma of the spinal epidural space, and their histogenesis and differential diagnosis are described. The diagnosis of Ewing's sarcoma, which is essentially an undifferentiated tumour, depends largely on the exclusion of several other neoplasms with morphological similarities. With these two cases, 43 extraosseous Ewing's sarcomas have been reported to date, seven of which were epidural in location.

Adolescent↗

Symptomatic subependymoma. Report of 21 cases with review of the literature.

Of 48 cases of subependymoma reported to date, 22 were associated with symptoms. In a personal series of 47 additional cases of subependymoma reviewed by the author, 21 were symptomatic. The mean age of patients with symptom-producing subependymomas was 39 years, that is, 20 years younger than that of patients with asymptomatic tumors. Symptoms were most often produced by large tumors, particularly those arising from the septum pellucidum (100%), the floor of the fourth ventricle (65%), and the lateral ventricular walls (55%). The majority of symptomatic tumors displayed the classic gross and microscopic features of subependymomas; however, large tumors more frequently demonstrated cyst formation, microcalcification, and vessel degeneration accompanied by hemorrhage. Of all subependymomas, 15% were microscopically composed of an admixture of classic subependymoma and cellular ependymoma; of these, one-half occurred within the first decade, all were situated in the fourth ventricle, and 80% were symptomatic. In contrast to pure subependymomas, the mortality rate of patients with mixed tumors was 80%, reflecting their growth potential, large size, and dangerous location.

Adult↗

Neutral glycolipid composition of primary human brain tumors.

Neutral glycolipids (NGL) were isolated and quantitated in 98 primary human brain tumors; 19 low grade astrocytomas (LGA), 12 anaplastic astrocytomas (AA), 37 high grade astrocytomas (HGA), 18 oligodendroglial tumors, and 12 primitive neuroectodermal tumors (PNET). In 38 of these, the nature of the hexose in the cerebroside was determined using immunothin-layer chromatographic techniques. Galactosylceramide (GalCer) was the major ceramide monohexoside (CMH), and glucosylcerebroside never comprised more than 6% of this fraction in any tumor type. Furthermore, there was no correlation between the proportion of glucosylcerebroside and histological diagnosis. AA had the most characteristic neutral glycolipid pattern, with high levels of total lipid, total neutral glycolipid, CMH, and ceramide dihexoside (CDH) but low water contents. Consistent with this glycolipid composition is the finding that AA usually had neither ceramide trihexoside (CTH) nor globoside. Oligodendrogliomas were somewhat similar to AA in having high levels of CMH and infrequently having CTH or globoside. However, oligodendrogliomas had low water and total lipid contents. PNET had low levels of total lipid, total NGL, and CMH, but frequently contained CTH and globoside. LGA had high water contents but low levels of total lipid and CMH. HGA tended to have intermediate levels of almost all constituents analyzed, probably reflecting the pronounced cellular heterogeneity of these tumors. The frequent presence of GalCer in astrocytomas raises the possibility that some of these contain a population of cells that are related to the oligodendroglial lineage. However, the low amounts of GalCer and infrequent presence of sulfatide in PNET is consistent with their lack of differentiation toward oligodendrocytes. It will be of interest to determine if the neutral glycolipid patterns reported here will correlate with patient survival and be of prognostic significance.

Astrocytoma↗

Intracranial plasma cell granuloma presenting as an optic neuropathy.

A 40-year-old man presented with a left optic neuropathy. Magnetic resonance imaging demonstrated a contrast-enhancing mass along the course of the left trigeminal nerve and in the region of the left cavernous sinus with suprasellar extension. Preoperatively, he had a serum polyclonal gammopathy. Pathologic diagnosis was an intracranial plasma cell granuloma. The patient responded to high-dose steroids with resolution of his optic neuropathy, marked decrease in the size of the mass, and resolution of the serum polyclonal gammopathy. Intracranial plasma cell granuloma is a rare lesion; only 11 cases have been described in the literature. Almost half of the patients presented with vision loss as their chief complaint.

Adult↗

Leptin and leptin receptor in anterior pituitary function.

Leptin is a 16 kDa protein that exerts important effects on the regulation of food intake and energy expenditure by interacting with the leptin receptor in the brain and in many other tissues. Although leptin is produced mainly by white adipose tissue, several laboratories have shown low levels of leptin production by a growing number of tissues including the anterior pituitary gland. Many studies have implicated leptin in anterior pituitary function including the observation that homozygous mutations of the leptin receptor gene led to morbid obesity, lack of pubertal development and decreased GH and TSH secretion. In addition, leptin functions as a neuroendocrine hormone and regulates many metabolic activities. Leptin also interacts with and regulates the hypothalamic-pituitary-adrenal, the hypothalamic-pituitary-thyroid and the hypothalamic-pituitary-gonadal axes. All of the anterior pituitary cell types express the leptin receptor. However, leptin has been localized in specific subtypes of anterior pituitary cells indicating cell type-specific production of leptin in the anterior pituitary. Subcellular localization of leptin indicates co-storage with secretory granules and implicates hypothalamic releasing hormones in leptin secretion from anterior pituitary hormone cells. Leptin signal transduction in the anterior pituitary has been shown to involve the janus protein-tyrosine kinase (JAK)/signal transducer and activation of transcription (STAT) as well as suppressor of cytokine signalling (SOCS). These proteins are activated by tyrosine-phosphorylation in anterior pituitary cells. The various steps in pituitary leptin signal transduction remain to be elucidated.

Aging↗