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Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 325 records · Page 18Linked to original sources
PubMed1988

Dysembryoplastic neuroepithelial tumor: a surgically curable tumor of young patients with intractable partial seizures. Report of thirty-nine cases.

This report concerns the clinicopathological features of 39 cases of a morphologically unique and surgically curable group of neuroepithelial tumors associated with medically intractable partial complex seizures. All were supratentorial and characterized by intracortical location, multinodular architecture, and heterogeneity in cellular composition. The constituent cells included astrocytes, oligodendrocytes, and neurons. Because neuronal atypia was often inapparent, the tumors superficially resembled mixed oligoastrocytomas. The term "dysembryoplastic neuroepithelial tumor" (DNT) is proposed for these distinctive lesions, the clinicopathological features of which suggest a dysembryoplastic origin. With the exception of the occurrence of headaches in 2 patients, partial complex seizures were the exclusive symptom. Age at onset of symptoms ranged from 1 to 19 years (mean 9 years). In addition to the chronic nature of the seizures (range, 2 to 18 years; mean, 9 years), one-third of the patients showed radiological features, such as focal cranial deformity, indicating that the tumors had an early onset and were of long standing. In most cases, computed tomography showed a "pseudocystic," well-demarcated, low density appearance associated in some cases with focal contrast enhancement (18%) or calcific hyperdensity (23%). The tumor involved the temporal lobe in 24 patients (62%), the frontal lobe in 12 (31%), and the parietal and/or occipital lobe in 3 cases. Although tumor removal was considered incomplete or subtotal in 17 patients (44%), long term follow-up (range, 1 to 18 years; mean, 9 years) showed neither clinical nor radiological evidence of recurrence in any patient. Comparison of the survival data of the 13 subjects who had undergone postoperative radiotherapy with 26 who had not indicated that radiation therapy was of no obvious benefit. The identification of DNT has therapeutic and prognostic implications because aggressive therapy can be avoided, thus sparing these young patients the deleterious long term effects of radio- or chemotherapy.

Adolescent↗
PubMed1988

Neoplasms of the vagus nerve.

A tumor of the vagus nerve often is discovered unexpectedly at operation. We report 36 of these rare neoplasms in 35 patients. The majority of the tumors presented as a mass in the upper cervical or parapharyngeal region. Usually the mass was asymptomatic. The following types and frequencies of neoplasms of the vagus nerve were noted: paragangliomas, 50%; neurilemmomas, 31%; neurofibromas, 14%; and neurofibrosarcomas, 6%. Surgical resection, with preservation of the vagus nerve when possible, is the treatment of choice. The clinical features, diagnosis, management, and prognosis of the tumors are presented. Special problems that occur with vagal neoplasms include postoperative dysfunction, catecholamine secretion, and intracranial or skull-base extension.

Adolescent↗
PubMed1988

Metastases of central nervous system neoplasms. Case report.

Tumor-to-tumor metastasis is a rare occurrence. Fewer than 100 cases have been reported, many being metastases from carcinomas to benign intracranial neoplasms, most often meningiomas. A case is presented of carcinoma metastatic to a glioma. The patient, who presented for evaluation of bifrontal headache, was found on computerized tomography to have a partially calcified right frontal mass. Craniotomy revealed an oligodendroglioma containing foci of adenocarcinoma. Further work-up disclosed an infiltrative ductal adenocarcinoma of the breast. It has been suggested that tumors of the central nervous system may provide a fertile substrate or an immunological "haven" for metastases.

Adenocarcinoma↗
PubMed1988

Choroid plexus papillomas: long-term follow-up results in a surgically treated series.

The medical records and histological specimens from 26 patients with choroid plexus papillomas operated on at one institution were reviewed retrospectively. Four patients died perioperatively, and 21 of the remaining 22 patients were followed through March, 1986; the patient lost to follow-up review was last seen 14 years postoperatively. Of the 14 patients who underwent gross total removal of their tumor, one had a recurrence at 11 years postoperatively and two died in the perioperative period. Of the 12 patients who underwent subtotal removal of their tumor, two died in the perioperative period. The two patients who did not have radiation therapy postoperatively are free of apparent disease at 6 and 8 years after their operation. Eight patients underwent radiation therapy after subtotal removal of their tumor; four of these remain alive and well, and four have died of progressive disease. The role of irradiation in the treatment of subtotally resected lesion remains controversial, but this therapy is thought to be indicated for recurrent disease after a surgical excision that is as complete as possible. Histopathologically, the presence of occasional mitotic figures, microscopic infiltration, ependymal differentiation, or mild to moderate atypia was not correlated with likelihood of complete resectability or tendency to recurrence.

Adolescent↗
PubMed1988

Membranous basal cell adenoma of the parotid gland. Malignant transformation in a patient with multiple dermal cylindromas.

The rare association of dermal cylindroma (turban tumor), trichoepithelioma, eccrine spiradenoma, and membranous basal cell adenoma of the parotid gland has been previously reported. It is believed that this combination represents a peculiar inherited tumor diathesis involving neoplasms of presumed ductal origin, eccrine in the skin and intercalated in the parotid gland. We describe a patient in whom the basal cell adenoma of the parotid gland underwent malignant transformation.

Adenoma↗
PubMed1987

Thymoma. A clinicopathologic review.

The clinical and pathologic features of 283 patients with thymoma treated at the Mayo Clinic (147 female and 136 male; ages 16 years to 90 years; mean, 52 years) were examined. Forty-six percent of the patients had myasthenia gravis and 10% had other paraneoplastic phenomena. The tumors were locally invasive at operation in 32%, including 6% with metastasis to lung or pleura. Intrathoracic recurrence was noted postoperatively in 15% of those who had total excision and distant metastasis developed in 3% of patients. Thirteen percent died of their thymomas and 16% died of myasthenia. Overall 5-year survival was 67% and 10-year survival was 53%. Poor prognostic factors included presence of tumor-related symptoms, large tumor size, local invasion or metastasis in initial operation, and predominantly epithelial histologic features. Although true thymomas are composed of cytologically benign elements, they show a propensity for local invasion and intrathoracic recurrence. They rarely metastasize outside the thorax.

Adolescent↗
PubMed1987

Endodermal sinus tumor (yolk sac tumor) of the ear.

Endodermal sinus tumors (yolk sac tumors) are malignant germ cell tumors that usually arise in the gonads. We report what is, to our knowledge, the first known case of an endodermal sinus tumor of the ear. The tumor was present in a developmentally delayed child with an abnormal temporal bone and exhibited histopathologic and immunocytochemical features identical to those of endodermal sinus tumors of gonadal origin. The tumor resolved after chemotherapy, and the patient remained alive without evidence of disease at the time of this writing. The purpose of this report is to add a rare tumor to the differential diagnosis of neoplasms of the ear in children and to familiarize otorhinolaryngologists and head and neck surgeons with its pathologic features and clinical management.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

A rare cause of acromegaly: ectopic production of growth hormone-releasing factor by a bronchial carcinoid tumor.

Ectopic production of growth hormone-releasing factor (GRF) is a rare cause of acromegaly. In addition to its production by gangliocytomas, both hypothalamic and intrasellar, in rare cases various neuroendocrine neoplasms produce the substance, with resultant growth hormone cell hyperplasia of the pituitary and acromegaly. We report an endocrinologically well-documented case of a GRF-producing bronchial carcinoid tumor in which the associated acromegaly was cured by lobectomy.

Acromegaly↗
PubMed1987

Postoperative radiotherapy of intracranial ependymoma in pediatric and adult patients.

In 33 patients undergoing operation and postoperative irradiation for intracranial ependymomas between January 1963 and December 1983, the tumor was grade 1 or 2 in 26 (79%) patients and grade 3 or 4 in 7 (21%). Operation consisted of only biopsy in 1 (3%), subtotal removal of tumor in 28 (85%), and gross total resection in 4 (12%). All patients received brain irradiation with a median dose of 4800 cGy. Seventeen (52%) patients also received spinal axis irradiation (median dose, 3000 cGy) which included 5 with high-grade tumors and 12 with low-grade infratentorial tumors. The relapse-free and overall survival rates at 5 years were 61% and 62%, respectively. Prognostic factors analyzed for statistically significant survival differences included age, sex, hydrocephalus, site, grade, extent of operation, extent of brain field, spinal axis irradiation, and brain dose. Grade was the only significant factor found: the 5-year survival of patients with low-grade ependymomas, 71%, was significantly better (p less than 0.04) than that of patients with high-grade ependymomas, 29%. Among the 31 patients evaluable for patterns of failure, treatment failed in 12 (39%) (10 only in the brain, 1 in the brain and spinal cord, and 1 only in the spine). All but one of the brain failures were at the site of the original primary lesion. Treatment failed in 4 of the 6 (67%) patients with high-grade tumor but in only 8 of the 25 (32%) with low grade tumor. Among the 7 low-grade infratentorial ependymomas treated with brain irradiation only, there was 1 treatment failure (in the spine; salvaged with further irradiation). Among the 12 patients with low-grade infratentorial tumors who received spinal axis irradiation, treatment failed in 1 (8%) (in the spine and also in the brain; patient subsequently died of disease). Nineteen (58%) patients remain alive; all but 2 of the patients who had recurrence died of their disease. This retrospective study suggests that: (a) patients with high-grade tumors have significantly poorer survival compared with those with low-grade tumors; (b) the main cause of death in ependymoma patients is intracranial failure at the primary site; and (c) craniospinal axis irradiation may not be necessary for patients with low-grade infratentorial ependymoma (localized irradiation alone may be adequate).

Adolescent↗
PubMed1987

The pituitary gland in the Laurence-Moon syndrome.

The apparent hypogonadism in patients with the Laurence-Moon syndrome has been variably attributed to unresponsiveness of target organs to gonadal hormones, primary end-organ failure, hypothalamic dysfunction, or pituitary failure. We report the first immunocytologic study of the pituitary gland in this rare disorder. No morphologic abnormalities were noted. The numbers and immunoreactivities of adenohypophyseal cell types were normal. No microscopic abnormalities were evident in the hypothalamus and target organs. The results of our study are consistent with recent biochemical data that suggest that pituitary function is normal in patients with this syndrome.

Adolescent↗
PubMed1987

A histologic and cytologic method for the spatial definition of gliomas.

Because of the increasing application of stereotactic neurosurgical techniques not only in the diagnosis but also in the treatment of brain tumors, a demand for data regarding the spatial delimitation of gliomas is being created. Traditional histologic criteria were not established for detecting isolated tumor cells located at the boundaries of gliomas. Standard histologic techniques used for processing surgical specimens result in preparations of insufficient quality to allow the detection of minimal tumor infiltrates within normal brain parenchyma. Consequently, histologic examination has been considered an unreliable method of determining the boundaries of gliomas. In this study, we describe in detail an improved technique of biopsy specimen preparation that involves the use of glutaraldehyde-fixed and hemalum-phloxine-stained paraffin sections as well as alcohol-fixed and hemalum-phloxine-stained smears. In concert, these methods allow visualization of delicate cytologic details and are complementary in assessing the presence of isolated tumor cells at the periphery of gliomas. We define morphologic criteria for the accurate identification of isolated neoplastic cells and for their distinction from normal or reactive glial elements. These morphologic criteria include classic cytologic features of malignant lesions (such as nuclear pleomorphism and hyperchromasia) as well as the assessment of tumor architecture and cellular spatial relationships.

Astrocytoma↗
PubMed1987

Stereotactic histologic correlations of computed tomography- and magnetic resonance imaging-defined abnormalities in patients with glial neoplasms.

In 39 patients who harbored previously untreated astrocytomas (21 patients), oligoastrocytomas (9 patients), or oligodendrogliomas (9 patients), computed tomographic (CT) and magnetic resonance imaging (MRI) findings were correlated with stereotactic serial biopsy findings. The 39 patients were classified as having one of three types of tumor: type I (1 patient), which consisted only of circumscribed tumor tissue; type II (26 patients), which consisted of tumor tissue and isolated tumor cells; or type III (11 patients), which consisted of intact parenchyma infiltrated by isolated tumor cells. (In one patient, the biopsy sampling was inadequate for determining the type of tumor.) In high-grade lesions, tumor tissue was obtained from CT contrast-enhancing regions, and the area of enhancement accurately defined the tumor tissue volume. In low-grade lesions, tumor tissue was hypodense and indistinguishable from parenchyma infiltrated by isolated tumor cells on both CT and MRI. Isolated tumor cells usually extended as far as the prolongation of T2 on T2-weighted MRI of high-grade and low-grade tumors. CT and MRI detection of boundaries and stereotactic serial biopsies are necessary for the demarcation of glial neoplasms into tumor tissue and isolated tumor cell volumes as well as for the determination of the spatial extent of each component. This information is important for determining appropriate treatment.

Adolescent↗
PubMed1987

Malignant peripheral nerve sheath tumor. An immunohistochemical study of 62 cases.

Malignant peripheral nerve sheath tumor (MPNST) commonly presents a diagnostic challenge and may resemble a variety of other soft tissue neoplasms microscopically. The authors have examined 62 examples of MPNST immunohistochemically, using antibodies to S-100 protein, myelin basic protein (MBP), and Leu-7, all of which are potential neural markers. Sixty-eight percent of all cases expressed at least one of these three determinants, representing a higher rate of immunoreactivity than that seen for single nervous system antigens in previous studies. Conjoint reactivity for S-100/Leu-7, S-100/MBP, and MBP/Leu-7 was seen in 34%, 34%, and 24% of cases, respectively. This coexpression of antigens is important, because none of them in isolation is immunospecific for nerve sheath tumors. In addition, stains for epithelial membrane antigen were reactive in two epithelioid tumors in this series, and eight spindle-cell neoplasms demonstrated desmin positivity. Analyses for cytokeratin, carcinoembryonic antigen, and Factor VIII-related antigen were negative in all cases. These results indicate an overlap between the immunocytochemical attributes of malignant peripheral nerve sheath tumors and other soft tissue sarcomas and emphasize the desirability of assessing multiple neural markers in such cases.

Antigens↗
PubMed1987

The effects of dextrose infusion and head position on neurologic outcome after complete cerebral ischemia in primates: examination of a model.

The hypothesis that iv dextrose infusion prior to--and head position during--cerebral ischemia would influence the severity and pattern of neurologic injury was tested in primates. Fifteen pigtail monkeys weighing 3.3 +/- 0.2 kg (mean +/- SE) were subjected to 17 min complete cerebral ischemia followed by 24 h intensive care treatment and neurologic assessment for an additional 72 h. Monkeys were given 50 ml iv infusions of either dextrose 5% in 0.45% saline solution (n = 8) or lactated Ringer's solution (n = 7) during the preparatory period. This volume corresponds to approximately 1 1/70 kg individual. These same monkeys were placed in either the lateral (n = 3), prone (n = 5), or supine (n = 7) position during the ischemic period. Two monkeys failed to meet preestablished protocol criteria and were excluded from data analysis. Blood glucose immediately preischemia in the dextrose-treated group (181 +/- 19 mg X dl-1) was not significantly greater than in the group given lactated Ringer's solution (140 +/- 6 mg X dl-1; P = 0.07). Dextrose infusion resulted in significantly greater cerebral injury at 96 h postischemia when comparing both neurologic (P less than 0.05) and histopathology (P less than 0.05) scores. Specifically, dextrose administration resulted in the greatest injury to the insular cortex, thalamus, Purkinje cells, and substantia nigra. Although blood glucose was less than 250 mg X dl-1 in all monkeys at the time of complete cerebral ischemia, there was a high correlation between blood glucose rank and neurologic function rank (rs = 0.76; P less than 0.005). The authors were unable to note any effect of head position on the distribution of histopathologic lesions. Prior to removing the brain for histopathologic studies, four monkeys were given repeat infusions of 50 ml dextrose 5% in 0.45% saline solution over 11 +/- 1 min. These infusions produced increases in blood glucose from 56.7 +/- 7.6 to 244 +/- 24.9 mg X dl-1 (P less than 0.01) and increases in brain glucose from 1.64 +/- 0.22 to 5.11 +/- 0.48 mumol X g-1 (P less than 0.01).

Animals↗
PubMed1987

Diffuse intraductal papillary adenocarcinoma of the pancreas.

The incidence of multicentricity in pancreatic cancer has been reported to be as high as 38%. Recent surgical and autopsy series have documented multicentric disease and the presence of carcinoma in situ in association with invasive carcinoma. Described are the clinical and pathologic findings in a 41-year-old woman who had total pancreatectomy for diffuse ductal transformation to papillary adenocarcinoma associated with a wide spectrum of extensive ductal epithelial changes. The significance of epithelial abnormalities as they relate to the occurrence of multicentric tumor is discussed, and the findings in this patient are compared with those of other distinctive clinicopathologic entities. Despite an apparently favorable outcome and 20-month disease-free follow-up in this patient, no good evidence indicates that age, extent of procedure, or lack of tumor invasion has prognostic significance in pancreatic cancer.

Adenocarcinoma, Papillary↗
PubMed1987

Stereotactic resection of juvenile pilocytic astrocytomas of the thalamus and basal ganglia.

Six patients with juvenile pilocytic astrocytomas of the thalamus or basal ganglia underwent seven computer-assisted stereotactic laser craniotomies with complete or nearly complete removal of the tumor in all cases. The tumor was located in the right basal ganglia in one patient, the left basal ganglia in one patient, and the left thalamus in four patients. Postoperative assessment of the completeness of tumor removal was confirmed by contrast-enhanced computed tomographic scanning within the first 2 weeks after operation. None of the patients was neurologically worse after the procedure, and five were improved. The duration of follow-up ranged from 6 months to 3.5 years. In this group of patients, the computer-assisted, stereotactically guided resection of these deeply located, benign tumors was accomplished with no morbidity or mortality.

Adolescent↗