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Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 343 records · Page 19Linked to original sources

Imaging-based stereotaxic serial biopsies in untreated intracranial glial neoplasms.

Forty patients with previously untreated intracranial glial neoplasms underwent stereotaxic serial biopsies assisted by computerized tomography (CT) and magnetic resonance imaging (MRI). Tumor volumes defined by computer reconstruction of contrast enhancement and low-attenuation boundaries on CT and T1 and T2 prolongation on MRI revealed that tumor volumes defined by T2-weighted MRI scans were larger than those defined by low-attenuation or contrast enhancement on CT scans. Histological analysis of 195 biopsy specimens obtained from various locations within the volumes defined by CT and MRI revealed that: contrast enhancement most often corresponded to tumor tissue without intervening parenchyma; hypodensity corresponded to parenchyma infiltrated by isolated tumor cells or in some instances to tumor tissue in low-grade gliomas or to simple edema; and isolated tumor cell infiltration extended at least as far as T2 prolongation on magnetic resonance images. This information may be useful in planning surgical procedures and radiation therapy in patients with intracranial glial neoplasms.

Adolescent↗

Prolactin-secreting adenomas: the preoperative response to bromocriptine treatment and surgical outcome.

Controversy exists regarding the effects of bromocriptine on the success of transsphenoidal surgery for patients with prolactinomas. Various studies on this drug have reported adverse effects, improvement, and no effect upon the subsequent surgical outcome. The authors have retrospectively reviewed the case histories of 55 patients with immunocytochemically confirmed prolactin-secreting pituitary adenomas operated on by a transsphenoidal approach between 1981 and 1985. All patients had received bromocriptine in a variety of doses and for variable durations prior to surgery. Thirty-nine patients were women and 16 were men, with an age range of 8 to 72 years. Basal prolactin levels prior to bromocriptine treatment ranged from 38 to 100 ng/ml in 11 patients, from 101 to 200 ng/ml in 12, and greater than 200 ng/ml in 29. The "cure" rates were 54%, 58%, and 38%, respectively. Thirty-one patients had microadenomas, with a postoperative cure rate of 68%; 12 had diffuse expansive adenomas, with a 17% cure rate; and 12 had grossly invasive tumors, with a 17% cure rate. A response to preoperative bromocriptine therapy was defined as a return of the basal prolactin level to normal: 18 patients were responders and 29 were hyporesponders; in eight the data were not available. The postoperative cure rate was 50% for the responders and 31% for the hyporesponders. Taking into account the distribution of tumor type, there was no actual difference in outcome between the responder and the hyporesponder groups. The total bromocriptine dose received preoperatively was nearly identical for all groups. No significant differences in the frequency or extent of fibrosis, calcification, or prolactin immunoreactivity were observed in the 55 patients when compared with 26 control prolactinomas not treated with bromocriptine. It is concluded that short-term bromocriptine treatment does not adversely affect surgical outcome in any of the prolactin-secreting adenoma groups, nor does response or lack of response to bromocriptine predict surgical outcome.

Adenoma↗

Pituitary adenomas of the multiple endocrine neoplasia type I syndrome.

In a series of 1,500 pituitary adenomas surgically resected at Mayo Clinic, 41 (2.7%) occurred in the setting of multiple endocrine neoplasia, type I (MEN-I). Of the 40 patients (18 males, 22 females), 21 (52%) presented with clinical evidence of a pituitary neoplasm, 13 with hyperparathyroidism, and two with functional islet cell tumor. Of the 41 tumors, 11 (27%) were microadenomas, and 30 (73%) were macroadenomas. Immunocytochemical studies demonstrated the following reactivities: GH (4), GH/PRL (6), GH/PRL/glycoprotein (7), GH/ACTH/glycoprotein (1), PRL (16), PRL/TSH (1), ACTH (3), and null cell adenoma (3). We conclude that, in comparison with pituitary adenomas occurring in the general population, those occurring in association with MEN-I are (1) more often endocrinologically functional, (2) more frequently GH- or PRL-producing, and (3) clinicopathologically similar in terms of the subjects age and sex as well as of tumor size and invasiveness.

Adenoma↗

Central nervous system tumors.

In this article the authors deal with the morphology of primary tumors of the central nervous system and its coverings. The discussion includes astrocytoma variants/glioblastoma, ependymoma and its variants, subependymoma, choroid plexus papilloma and carcinoma, embryonal CNS tumors, neuronal neoplasms, meningioma, dural hemangiopericytoma (angioblastic mengioma), and hemangioblastoma.

Central Nervous System Diseases↗

Paraganglioma of the cauda equina region. Clinicopathologic study of 31 cases with special reference to immunocytology and ultrastructure.

Thirty-one paragangliomas of the cauda equina region were studied (18 men and 13 women, ages 30-71 years [mean, 51 years]). Symptoms (1 day to 15 years in duration; mean, 48 months) included low back pain (87%), sensory/motor deficits (35%), urinary/fecal incontinence (13%), and paraplegia (6%). All patients studied had some myelographic block. Cerebrospinal fluid protein level ranged from 56 to 7000 mg/dl (mean, 1109 mg/dl). Most tumors were limited to the filum terminale, although one also involved the conus medullaris and two clearly arose from a caudal nerve root. All but one were entirely intradural. The tumor was totally excised in 26 cases; these patients remain disease-free. Of three patients whose tumors were excised subtotally, two received radiotherapy; the one non-radiated patient died of tumor-related complications. No autopsy was performed. One partially encapsulated tumor that had been subjected to biopsy and irradiation presented 1 year later with osseous invasion and retroperitoneal extension; 20 years after subtotal excision, this patient is alive but paraplegic. Morphologically, all tumors resembled paraganglioma at other sites. Cytologic atypia and mitotic activity generally were absent to mild. Fourteen (45%) cases showed ganglionic differentiation. All tumors tested were immunoreactive for neuron-specific enolase and neurofilament protein, and most showed somatostatin or serotonin reactivity. S-100 protein immunoreactivity was noted in sustentacular cells and, to a lesser extent, within chief cells and neurons. The authors conclude that paragangliomas are largely benign and encapsulated and respond to simple resection. When surgically feasible, gross total removal should be the goal of surgery. When subtotal resection is necessary or when local invasion leaves a question as to completeness of tumor removal, irradiation seems mandatory although far from guaranteeing prevention of recurrence. Biopsy alone is undesirable.

Adult↗

Malignant peripheral nerve sheath tumors. A clinicopathologic study of 120 cases.

A review was done of 120 cases of malignant peripheral nerve sheath tumor (MPNST) seen during a 71-year period. Of the 120 patients, 52 were males and 68 were females with a mean age at diagnosis of 35.3 years; 12 patients were younger than 20 years. The series included 62 (52%) patients with neurofibromatosis, 13 (11%) with postradiation sarcomas, and 19 (16%) with metaplastic foci. The incidence of MPNST arising in neurofibromatosis was 4.6% in the current series and 0.001% in the general clinic population. Tumors greater than 5 cm and the presence of neurofibromatosis adversely affected the prognosis (P less than 0.05). When both features were present, survival was greatly decreased. Patients with tumor in the extremities did better than those with head or neck lesions. Metaplastic foci or previous radiation at the tumor site did not alter the prognosis. Each tumor was graded 1 to 4 on the basis of cellularity, pleomorphism, mitotic index, and necrosis. No significant correlation was noted between survival and either grade or mitotic rate. Survival was improved when total rather than subtotal resection was done. This was most marked in patients with a small lesion, which may reflect the difficulty in adequately excising large tumors. Adjuvant radiation or chemotherapy did not appear to affect survival. The MPNST is an aggressive uncommon neoplasm, and large tumor size, the presence of neurofibromatosis, and total resection are the most important prognostic indicators.

Adolescent↗

The pathobiologic features of carcinomas of type II pneumocytes. An immunocytologic study.

Adenocarcinomas of the lung without squamous differentiation or obvious mucus production from 51 patients were studied. Twenty-eight tumors (55%), when stained with rabbit anti-human surfactant apoprotein antiserum by the peroxidase-antiperoxidase method, demonstrated characteristic nuclear inclusions. Most of these tumors could be identified histochemically by the presence of eosinophilic, periodic acid-Schiff (PAS)-positive nuclear inclusions. In patients with apoprotein-immunoreactive tumors there were nine deaths due to tumor (32%) within 5 years of diagnosis. Eight of the nine deaths occurred in patients whose tumors exceeded 3 cm in diameter; an equal number of patients were smokers. The average age of patients with apoprotein-positive tumors was 67.3 years, a figure greater than that for patients with apoprotein-negative tumors (61.4 years). Five of the 23 patients with apoprotein-negative tumors died of their neoplasms; in two of the subjects the tumors exceeded 3 cm in diameter. In that no significant difference in survival was observed in patients with apoprotein-positive and apoprotein-negative tumors, it was concluded that subclassification of adenocarcinomas of the lung as apoprotein-positive, i.e., type II pneumocytic, or as apoprotein-negative, is of no clinical or prognostic significance. Nonetheless, peripheral tumors measuring less than 3 cm in size and showing neither squamous differentiation nor obvious mucus production should be recognized as a prognostically favorable group in comparison with other types of lung carcinomas.

Aged↗

Radiotherapeutic management of adult intraspinal ependymomas.

Twenty-two adults with ependymomas of the spinal cord were treated with surgery and postoperative radiation between January 1963 and December 1983. The median age was 47 years. Nineteen patients had grade 1 lesions, two had grade 2 and one grade 3. Ten patients had the myxopapillary histologic subtype (all grade 1) and 12 had the cellular variant. There were 15 distal cord lesions originating from the conus medullaris, filum terminale and/or cauda equina. The remaining seven lesions arose more proximally. Fourteen patients had localized lesions involving one to three vertebral segments, while the remaining eight had extensive ependymomas spanning six to thirteen vertebral segments. The median time from onset of symptoms to diagnosis was 3 years. Surgical treatment consisted of biopsy only in three patients, subtotal removal in eleven patients and total removal in eight patients. Radiation was given to the spine only in all cases. Five patients received whole spine radiation; seventeen received partial spine treatment, appropriate for the length of the primary lesion. The median dose was 5000 cGy (range 3600-5700 cGy). The disease free survival at 5 and 10 years was 81 and 71%, respectively. Overall survival at 5 and 10 years was 95%. Seven of twenty-two (32%) patients failed. Factors analyzed for prognostic significance included age, sex, histology, extent of primary, location of primary within the cord, extent of surgical resection and dose. Too few grade 2 and 3 patients precluded meaningful statistical analysis of grade as a prognostic factor. Neither age, sex, histology, extent of primary, location of primary, nor extent of surgical removal significantly affected disease free or overall survival (p greater than 0.05). Four of nineteen (21%) patients with grade 1 lesions failed, while all three patients with grade 2 and 3 lesions did so. Half of the eight patients with extensive ependymomas failed compared to three of fourteen (21%) with limited ones. Six of seventeen (35%) patients failed at doses less than or equal to 5000 cGy while only one of five (20%) failed at doses greater than 5000 cGy. Patterns of failure were analyzed for the seven patients who failed. Six of the seven failures (86% of the failure group, 27% of the overall group) were local, that is, within the initial radiation field at the site of the original tumor. A single patient (grade 2) failed in the posterior fossa while remaining NED in the spinal cord (a head CT scan at initial work-up was negative).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

Leiomyoma of the bladder.

We report 5 cases of leiomyoma of the bladder and review the literature. Because of its size and location, this tumor usually is asymptomatic unless urinary tract function is affected. Excretory urography and computerized tomography were useful in identifying the location, consistency and size of the lesions. Small lesions can be managed with transurethral resection and large lesions require segmental resection. Cystectomy is not indicated.

Adult↗

Nonidentical expressions of multiple endocrine neoplasia, type I, in identical twins.

We studied 25-year-old HLA- and blood group-identical male twins who had multiple endocrine neoplasia, type I (MEN I). At the time of initial examination, one twin (case 1) had epigastric pain and diarrhea; he was cushingoid in appearance. Further evaluation revealed primary hyperparathyroidism, Zollinger-Ellison syndrome, Cushing's disease, and hyperprolactinemia. Immunostaining of a resected pituitary specimen demonstrated both prolactin and, to a lesser extent, growth hormone reactivity. The nontumorous adenohypophysis showed corticotropic hyperplasia. In contrast, the other twin (case 2) was asymptomatic. He had only primary hyperparathyroidism and hyperprolactinemia. An invasive pituitary adenoma was resected and showed similar proportions of cells with immunoreactive prolactin and those with growth hormone; no nontumorous gland was available for study. Apparently, factors other than heredity may play a role in the expression of MEN I.

Adenoma↗

Pathology of excessive production of growth hormone.

Since its clinical description in the last century, much progress has been made in our understanding of acromegaly. From an initial description of pituitary enlargement as just another manifestation of generalized visceromegaly, the pituitary abnormality has come to be recognized, in most instances, as the underlying aetiological factor. Gigantism and acromegaly are manifestations of disordered pituitary physiology, but the lesion responsible may be hypothalamic, adenohypophyseal or ectopic in location. The best known pathological hypothalamic basis for acromegaly is represented by a neuronal malformation or 'gangliocytoma'. It usually takes the form of an intrasellar gangliocytoma or, more rarely, a hypothalamic hamartoma. The neuronal elaboration of GHRH may play a role in the development of a growth hormone adenoma; the pituitary process may pass through an intermediate stage of somatotropic hyperplasia. When acromegaly has its basis in a pituitary abnormality, the lesion is almost exclusively an adenoma; the non-tumorous adenohypophysis shows no evidence of coexistent hyperplasia. Surprisingly, such tumours are more often engaged in the formation of multiple hormones rather than GH alone. They frequently produce not only GH and prolactin, the products characteristics of cells of the acidophil line, but also glycoprotein hormones, usually TSH. The spectrum of adenomas also varies in its degree of differentiation from a histogenetically primitive lesion, the acidophil stem cell adenoma, to well-differentiated tumours of varying cellular composition and hormone content. Each adenoma type has its clinicopathological, histochemical, immunocytological and ultrastructural characteristics. The isolation and characterization of GHRH has permitted the identification of neuroendocrine tumours, most of foregut origin, elaborating this releasing hormone. Such functional tumours induce hyperplasia of pituitary somatotrophs and may, on occasion, result in the formation of growth hormone adenomas. Resection of these GHRH-producing neoplasms results in reversal of endocrinological and sellar abnormalities. Future efforts should be directed toward the elucidation of the aetiology of pituitary adenomas, specifically whether they represent a proliferative process having its origin in endocrinological imbalance, presumably a hypothalamic abnormality, or whether it has a 'de novo' origin in the 'usual process of neoplastic transformation'.

Acromegaly↗

Duodenal gangliocytic paraganglioma. Clinicopathologic and immunocytochemical study of 11 cases.

The clinicopathologic features of 11 cases (8 in men) of duodenal gangliocytic paraganglioma are presented. The patients averaged 56 years of age; none showed evidence of phakomatosis. Ten tumors occurred in the second portion of the duodenum, and one arose in the third portion. All tumors were polypoid, and half presented with gastrointestinal bleeding. The neoplasms were composed of paraganglioma and carcinoid-like elements, neurons, and Schwann as well as sustentacular cells. All tumors behaved in a benign fashion after local resection or snare polypectomy; long-term follow-up (1-25 years; mean, 8.3 years) showed no recurrence in any case. Immunocytochemical examination demonstrated the presence of somatostatin, serotonin, and human pancreatic polypeptide within endocrine cells and neurons.

Aged↗

Primitive neuroectodermal tumor of the endometrium: report of two cases, one with electron microscopic observations.

Two primary primitive neuroectodermal uterine malignant tumors are reported. One initially had the appearance of neuroblastoma but after radiotherapy showed both glial and ganglionic differentiation. The second neoplasm exhibited medulloepithelial canals, as well as glial, neuroblastic, and focal neuronal differentiation. Both patients died with widespread metastatic disease after both radiotherapy and chemotherapy.

Carcinoma↗

Cryptic structural lesions in refractory partial epilepsy: MR imaging and CT studies.

Results of contrast material-enhanced computed tomography (CT) and T2-weighted spin-echo magnetic resonance (MR) imaging were correlated with pathologic findings in 25 patients treated surgically for refractory partial epilepsy. Of 12 lesions present, ten (83%) were detected by MR imaging and seven (58%) by CT scanning. Of nine low-grade gliomas, eight were detected by MR imaging and four by CT scanning. One posttraumatic scar and one case of temporal lobe atrophy were better demonstrated by MR imaging. A small, thrombosed arteriovenous malformation was the only lesion detected by CT scanning but not by MR imaging. No lesions were detected in 13 patients with mild gliosis and one patient with a 1.2-cm grade 1 astrocytoma. Although more sensitive than CT for detection of structural lesions in patients with refractory partial epilepsy, MR imaging resulted in a 25% false-negative diagnostic rate when a repetition time of 2,000 msec and echo time of 60 msec were used. Multi-echo imaging with at least one long echo time may be needed to increase the sensitivity of MR imaging in these patients.

Adolescent↗

Radiographic findings in 32 cases of primary CNS lymphoma.

Computed tomographic (CT) or angiographic (or both) findings were analyzed in 32 cases of pathologically proved primary non-Hodgkin lymphoma of the central nervous system. CT scans were available in 28 of the 32 cases. Thirty lesions were found in the 28 cases. In comparison with previous literature, the frequency of involvement of deep central structures (30%), multiple lesions (11%), and subependymal lesions (4%) was lower and that of lesions in the periphery of the supratentorial compartment was higher (46%). In agreement with previous literature, most of the lesions were of increased density (63%), enhanced (100%), and enhanced homogeneously (71%). Twenty-nine of the 32 patients underwent cerebral angiography. In 12 patients, a homogeneous vascular stain was found that appeared in the late arterial or early venous phase and had a meningiomalike pattern. This staining pattern has not been emphasized sufficiently in previous literature. It was believed that such an angiographic pattern in a dense, homogeneously enhancing parenchymal lesion is suggestive of a primary lymphoma of the central nervous system. Magnetic resonance imaging was performed in one patient with two lesions, and both lesions demonstrated prolonged T2 relaxation times.

Adolescent↗

The occurrence of dural invasion in pituitary adenomas.

This report describes 60 dural specimens from patients with pituitary adenomas treated by transsphenoidal microsurgery, and attempts to define more precisely the clinical and pathological correlation of microscopic dural invasion. Analysis of the adenomas was based on four characteristics; size, surgical invasiveness (based on the surgeon's assessment of involvement by tumor of bone, dura, or cavernous sinus), histological evidence of invasion, and immunohistochemical staining characteristics. The incidence of surgical invasiveness (24 cases, 40%) was greater than previously reported, but most important was the frequent occurrence of microscopic dural invasion (51 cases, 85%). There was a clear progression of microscopic evidence of dural invasion with increasing tumor size: 69%, 88%, and 94% of the dural specimens from microadenomas, macroadenomas, and tumors with suprasellar extension, respectively, showed microscopic dural invasion. A correlation of invasiveness with immunohistochemical classification of tumor type was not evident.

Adenoma↗

Pathology of invasive pituitary tumors with special reference to functional classification.

Pituitary adenomas may remain intrasellar or infiltrate dura and bone. Invasive adenomas are not considered to be malignant; in biological behavior they are between non-infiltrative adenomas and pituitary carcinomas. The latter are defined as tumors with subarachnoid, brain, or systemic metastasis. Invasion may be defined radiologically, operatively, or histologically. On the basis of operatively assessed tumor size and gross invasion of dura and bone as well as immunocytochemical and ultrastructural analysis of 365 pituitary adenomas, the following data were obtained. There were 23 growth hormone (GH)-cell adenomas: 14% microadenomas and 86% macroadenomas; their overall frequency of invasion was 50%. There were 24 prolactin (PRL)-cell adenomas: 33% microadenomas and 67% macroadenomas, with an overall frequency of invasion of 52%. Mixed GH-cell and PRL-cell adenomas were found in 35 cases; 26% were microadenomas and 74% were macroadenomas, and the overall frequency of invasion was 31%. Sixty patients had adrenocorticotropic hormone (ACTH)-cell adenomas (Cushing's disease): 87% microadenomas and 13% macroadenomas; the overall frequency of invasion was 25% (in 8% of microadenomas and 62% of macroadenomas). Twenty patients had ACTH-cell adenomas (Nelson's syndrome): 30% microadenomas and 70% macroadenomas; the overall frequency of invasion in these cases was 50% (in 17% of microadenomas and 64% of macroadenomas). Silent ACTH-cell adenomas, 100% macroadenomas, were found in 11 patients, with an 82% frequency of invasion. There were 32 follicle-stimulating and luteinizing hormone adenomas, all macroadenomas, with a frequency of invasion of 21%. Four patients had thyroid-stimulating hormone adenomas, all macroadenomas, with a 75% frequency of invasion. Null-cell adenomas were found in 93 cases: 2% microadenomas and 98% macroadenomas, with a frequency of invasion of 42%. There were 63 plurihormonal adenomas (GH, PRL, glycoprotein): 25% microadenomas and 75% macroadenomas, with a 50% overall frequency of invasion. Based on this study, and on their usual frequency of occurrence, the estimated rate of gross invasion by pituitary adenomas of all types is approximately 35%. It is concluded that immunocytochemical and ultrastructural characteristics of pituitary adenomas reflect the tendency of these tumors to infiltrate and hence may be of prognostic significance.

Adenoma↗