Biomedical subjects

B W Scheithauer

Publications and source records attributed to B W Scheithauer.

At least 289 records · Page 16Linked to original sources

PubMed1991

Subependymoma with rhabdomyosarcomatous differentiation: report of a case and literature review.

A unique gliomesenchymal neoplasm, consisting of a subependymoma, a form of low-grade glioma, and a rhabdomyosarcoma, is described. It arose and recurred in the brain stem of a 52-year-old man. Immunohistochemical studies demonstrated the presence of a neuroectodermal marker S-100 protein within some sarcoma cells. The occurrence of this rare tumor supports the concept that striated muscle may derive from a neuroectodermal precursor lesion.

Brain Neoplasms↗

PubMed1991

[Subependymal giant cell astrocytoma].

Subependymal giant-cell astrocytomas (SEGA) are rare brain tumors. They occur typically in the walls of the lateral ventricles and very seldom in the wall of the third ventricle. In our experience, all patients with SEGA have had tuberous sclerosis. Between January 1950 and May 1990, of our 345 patients with tuberous sclerosis 22 were found to have SEGA. The diagnosis being made histologically in symptomatic cases or by clinical or neuroradiologic methods. The histological, immunohistochemical and ultrastructural features of this unique tumor are discussed. To date, histopathologic methods have not resolved the issue of whether these tumors are exclusively astrocytic or neuronal in nature, or show features of both. Modern immunohistochemical and/or molecular-biological techniques will no doubt elucidate the histogenesis of this highly characteristic, albeit polymorphous tumor.

Adult↗

PubMed1991

Paraneoplastic anti-Purkinje and type I anti-neuronal nuclear autoantibodies bind selectively to central, peripheral, and autonomic nervous system cells.

Autoantibodies provide serologic markers for subacute cerebellar degeneration in the setting of gynecologic or breast cancer (anti-Purkinje cell cytoplasmic antibodies, PCAb), and for encephalomyeloradiculoneuropathies in the setting of small cell lung carcinoma (type I anti-neuronal nuclear antibodies, ANNA-I). PCAb and ANNA-I are not species-restricted in their specificities. The subject of this report is a systematic immunocytochemical investigation of the distribution and types of cells in the mouse central and peripheral nervous system that bind these IgG autoantibodies. Sera used for the study were from two patients with prototypic PCAb reactivity and two with prototypic ANNA-I reactivity, none of whom had evidence of other autoantibodies, and from four age- and sex-matched healthy control subjects. The patients' clinical features were consistent with the classic syndromes that have been reported with PCAb and ANNA-I, respectively. PCAb bound prominently to the cytoplasm of cerebellar Purkinje cells, and also to other large cytoplasm-rich neurons throughout the central nervous system, to neurons in sensory and sympathetic ganglia and myenteric plexus, and to cells of the adrenal medulla. ANNA-I, on the other hand, bound to virtually all neurons in the central and peripheral nervous system, including sensory and autonomic ganglia, myenteric plexus and cells of the adrenal medulla. An unanticipated finding was that immunoreactivity with ANNA-I was enhanced by fixing tissues briefly with formalin. Astrocyte processes were stained by PCAb and by ANNA-I (but not by the control sera). The cytoplasm of sciatic nerve Schwann cells was stained strikingly by PCAb, but ANNA-I did not bind to Schwann cells. Although it has not yet been determined whether or not PCAb or ANNA-I per se are pathogenic, it is apparent that they represent at least a component of an immune response that is initiated by tumor antigens. The distribution of these tumor-related antigens in the nervous system is consistent with the diversity of neurologic manifestations that can occur in individual patients with the associated paraneoplastic syndromes.

Aged↗

PubMed1991

Subependymal giant cell astrocytoma: a clinical, pathological, and flow cytometric study.

Of 345 patients with tuberous sclerosis complex evaluated at the Mayo Clinic from 1950 to 1989, 23 were identified as having brain tumors. In 20 of the 23, histological or clinical evidence showed the tumor to be a subependymal giant cell astrocytoma. A search of the Mayo Clinic tissue registry yielded 73 giant cell-containing astrocytomas and intraventricular gliomas exclusive of ependymomas. Reexamination revealed no further examples of subependymal giant cell astrocytoma in patients without features of the tuberous sclerosis complex. Considerable histological variation was observed in the 15 subependymal giant cell astrocytomas subjected to critical microscopic review. It is of note that no correlation was noted between either the histological features, such as atypia, mitoses, endothelial proliferations, necrosis, or the flow cytometric characteristics and the clinical course or the survival time of the patients.

Adolescent↗

PubMed1990

Tumors of the meninges: proposed modifications of the World Health Organization classification.

The present WHO classification of meningiomas has served us well. In keeping with the adage, "if it ain't broke, don't fix it," alterations should be made with due caution. These proposed modifications of the WHO classification are prompted by advances in our understanding of the pathobiology of meningeal neoplasms, as well as a need for an orderly scheme based upon factors of clinical importance. The author is well aware, that given the vastly differing technologies available to those utilizing the "blue book," its application must have a basis in routine histology rather than in "high-tech" procedures. No classification is ideal, but the modifications suggested represent a compromise between the pathologist's need for a complete morphologic exposition and the clinician's desire for a concise classification of therapeutic and prognostic significance.

Humans↗

PubMed1990

Radiotherapeutic considerations in the treatment of hemangioblastomas of the central nervous system.

Twenty-seven hemangioblastomas of the central nervous system were treated at the Mayo Clinic with radiation therapy from January 1963 to August 1983. Six patients had von-Hippel Lindau syndrome, and four presented with polycythemia. The median age among the 15 males and 12 females was 48 years (range 20-68). Two clinical groups were apparent: those that received postoperative radiation therapy for clinically suspect, or microscopically positive margins (6 patients) and those who underwent therapy for gross residual disease (20 patients). One patient did not fall into either group because his initially unresectable tumor was treated with planned pre-operative radiotherapy to 40 Gy and was subsequently successfully cured by surgery. Because the combined modality approach did not allow assessment of local control with radiation alone, he was excluded from the gross residual cohort in terms of time-dose relationship analysis. The cohort with gross residual disease was particularly unfavorable as 12 of these patients had developed 17 local recurrences prior to radiation. Three had multiple lesions, and four had the von-Hippel Lindau syndrome. In-field disease control appeared to be improved when patients were treated more aggressively. Patients treated to a dose of 50 Gy manifested local control in 4/7 (57%) vs 4/12 (33%) in patients treated to less than 50 Gy. In-field local control was also better if patients received a TDF greater than 75 (local control in 66%) vs a TDF of 65-75 (local control in 22%). Actuarial analysis of in-field disease control showed more aggressive treatment improved control whether analyzed by dose level (greater than or equal to 50 Gy vs less than 50 Gy, or TDF greater than 75 vs less than 75). Four of the six patients who received radiation therapy for microscopically positive or clinically suspect margins achieved local control. Both patients manifesting in-field relapse were successfully surgically salvaged. Overall survival for the entire group of 27 patients was 85%, 58%, 58%, and 46% at 5, 10, 15, and 20 years, respectively. Recurrence-free survival was 76%, 52%, and 42% at 5, 10, and 15 years, respectively. Half of all in-field recurrences had occurred by 2 years, but the remaining half recurred from 5.6 to 14.4 years. Patients who developed in-field failure usually died from disease with a median survival of only 1.5 years, but surgical salvage was accomplished in 4/12. Hydro-myelia developed in two patients and required operation. Surveillance for systemic tumors also was important and revealed seven benign and four malignant tumors.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1990

The pituitary gland in pregnancy: a clinicopathologic and immunohistochemical study of 69 cases.

A histologic and immunocytochemical study of 69 autopsy-obtained pituitaries from women who died during pregnancy, after abortion, or in the postpartum period revealed an accumulation of large chromophobic to slightly acidophilic and periodic acid-Schiff-negative pregnancy cells that were immunoreactive for prolactin but not for other pituitary hormones. This increase in the number of prolactin cells was confirmed by cell counts. Thus, pregnancy cells are capable of prolactin production. The finding of mitotic figures in such cells supports the view that they arise by multiplication from preexisting prolactin cells. With use of "mirror section" techniques, no mammosomatotrophs (cells immunoreactive for growth hormone and prolactin) were identified. Hyperplasia of prolactin cells was evident at 1 month of pregnancy and gradually disappeared within several months after delivery or abortion; the process of involution seemed to be retarded in the one lactating patient investigated. In some pituitaries, the accumulation of prolactin cells was so extensive that the hyperplastic foci resembled microadenomas. Another striking change in the pituitaries of pregnant women was appreciable reduction of immunostaining of gonadotropic cells, a process that was reversible as soon as 1 month after delivery. Among the 69 pituitaries studied, 8 noninvasive microadenomas (12%) were encountered (7 contained prolactin only and 1 was plurihormonal). Prolactin-producing adenomas were no more numerous or larger than were similar tumors encountered in nonpregnant women or normal men; thus, pregnancy neither initiates formation of pituitary adenomas nor accelerates their growth. In the pituitaries that harbored prolactin-producing adenomas, massive pregnancy cell hyperplasia was evident outside the tumor; thus, prolactin production by adenoma cells did not seem to suppress the proliferation of prolactin-containing pregnancy cells.

Adenoma↗

PubMed1990

Diagnosis of corticotropin-producing bronchial carcinoid tumors causing Cushing's syndrome.

Cushing's syndrome due to ectopic production of adrenocorticotropic hormone (corticotropin) has been recognized for many years. Traditionally, clinicians have thought that most cases were due to lung carcinomas and that the clinical manifestations differed from those for pituitary-dependent Cushing's syndrome. We report two cases of corticotropin-producing bronchial carcinoid tumors that were clinically and biochemically indistinguishable from pituitary-dependent Cushing's syndrome. Review of the literature revealed that bronchial carcinoid tumors are the most common cause of Cushing's syndrome due to ectopic secretion of corticotropin. On biochemical and anatomic studies, they are frequently indistinguishable from pituitary-dependent Cushing's syndrome and thus may be difficult to diagnose. Inferior petrosal sinus sampling for corticotropin and computerized imaging of the chest may be the best aids in making the diagnosis.

ACTH Syndrome, Ectopic↗

PubMed1990

Medulloblastoma--prognostic factors and outcome of treatment: review of the Mayo Clinic experience.

From March 1965 through December 1984, 58 patients (35 male and 23 female patients; median age, 17 years) with posterior fossa (PF) medulloblastoma underwent surgical treatment and postoperative radiation therapy at our institution. Radiation fields were the craniospinal axis in 39 patients, PF plus spinal axis in 12, PF in 6, and whole brain in 1. Median radiation doses were 43 Gy (22 to 60 Gy) to the PF and 34 Gy (6.2 to 50 Gy) to the spinal axis. Overall 5- and 10-year survivals were 50% and 33%, respectively; 5- and 10-year relapse-free survivals were 46% and 32%. Treatment failed in 34 patients (59%): in 18 who had irradiation to the craniospinal axis (13 had received 50 Gy or less to the PF) and in 16 who had a radiation field of less than the craniospinal axis. A statistically significant (P less than 0.05) improvement in 10-year survival was associated with the following prognostic variables: PF dose of 50 Gy or more, whole-brain irradiation, and spinal axis irradiation. In comparison with subtotal resection, total resection was correlated with better 10-year relapse-free survival but not overall survival. All five patients with initial treatment failure only in the spine had received a radiation dose of 30 Gy or less to the spinal axis. The 2-year survival after relapse was 46% with salvage chemotherapy or irradiation in 23 patients and 0% in the 11 patients who received no further treatment (P less than 0.01).

Adolescent↗

PubMed1990

Intermediate filaments in the human pituitary gland: an immunohistochemical study.

Normal pituitaries, pituitaries showing CHC and selected adenomas were assessed for their possible content of intermediate filaments (IF), using immunohistochemical techniques. Normal pituitaries were stained for each of the five known IF (Cytokeratins (CK), glial fibrillary acidic protein (GFAP), desmin, vimentin, and neurofilaments (NF]. Desmin could not be demonstrated, and NF staining was limited to processes in the posterior gland. In serial sections, CK was demonstrated in some corticotrophs, somatotrophs, and lactotrophs. Vimentin was limited to processes in the posterior gland. Folliculo-stellate cells (FSC), demonstrated by staining for S100 protein, exhibited a small subpopulation staining for CK, and another subpopulation staining for GFAP. GFAP was also demonstrated in glial processes in the posterior gland. Cells showing Crooke's hyaline change stained intensely for CK. Null cell adenomas did not stain for CK. Corticotroph adenomas, somatotroph adenomas, with or without fibrous bodies, and lactotroph adenomas contain CK-immunoreactive cells. We conclude that CK is the major IF present in the anterior pituitary gland, within some normal corticotrophs, somatotrophs and lactotrophs, and also in adenomas derived from these cells.

Adenoma↗

PubMed1990

The effects of dizocilpine maleate (MK-801), an antagonist of the N-methyl-D-aspartate receptor, on neurologic recovery and histopathology following complete cerebral ischemia in primates.

The present study was designed to determine if the noncompetitive excitatory amino acid antagonist, dizocilpine maleate, when administered after a 17 min period of complete cerebral ischemia in primates, would improve postischemic neurologic function and hippocampal histopathologic outcome when compared to placebo-treated animals. Ten pigtail monkeys were anesthetized and subjected to complete cerebral ischemia using an established neck tourniquet model. Five minutes postischemia, five monkeys received dizocilpine 300 micrograms/kg i.v. over 5 min, followed by an infusion of 150 micrograms/kg/h for 10 h. This produced plasma levels of the drug in excess of 30 ng/ml for the duration of the infusion. An additional five monkeys were treated with an identical volume of saline placebo. All monkeys received intensive care for the initial 24 to 48 h postischemia. At 96 h postischemia, there was no significant difference in neurologic function between the two groups (p = 0.53, with the placebo group having the numerically better outcome). There also was no significant difference between hippocampal histopathology scores between dizocilpine and placebo-treated monkeys. The authors conclude that dizocilpine is not an efficacious therapy in the treatment of neurologic injury that occurs following complete cerebral ischemia in this primate model.

Animals↗

PubMed1990

Free alpha subunit of the pituitary glycoprotein hormones. Measurement in serum and tissue of patients with pituitary tumors.

A solid-phase radioimmunoassay was developed that measures the free alpha subunits of pituitary glycoprotein hormones (alpha PGpHs) and has negligible cross-reactivity with the intact hormones (less than 0.014% for thyroid-stimulating hormone [TSH], less than 0.1% for human chorionic gonadotropin [hCG], 0.8% for luteinizing hormone [LH], and 2.0% for follicle-stimulating hormone [FSH]). The assay is standardized with the alpha subunit of hCG but also reacts well with the alpha subunits of the other glycoprotein hormones (84% for alpha TSH, 77% for alpha FSH, and 64% for alpha LH). Concentrations as low as 0.3 micrograms/L can be reliably measured, and the 97.5% reference range in 27 healthy adults, including postmenopausal females, is less than or equal to 1.2 micrograms/L. Elevated preoperative alpha PGpH concentrations were found in 45 (9.4%) of 479 sera from patients with pituitary adenoma and 3 (4.5%) of 66 patients with nonadenomatous sellar lesions. Postoperative alpha PGpH levels were lower in 30 of 39 adenoma patients and 2 of 3 nonadenoma patients. In five (1%) of the patients with pituitary adenomas, alpha PGpH was the only elevated serum hormone marker. Serum values of alpha PGpH correlate weakly with alpha subunit immunocytochemical staining--95% of those with negative staining have normal alpha PGpH values, but only 18% of those with positive staining have elevated alpha PGpH values.

Adenoma↗

PubMed1990

Cerebral sparganosis. Case report.

The tapeworm Spirometra mansonoides infects man worldwide, particularly in Asian countries. Rarely, the central nervous system is involved; such a case is presented here. In the total of 12 reported cases, including the case described, the worm presented clinically as a mass suspicious for neoplasm or chronic abscess cavity. Surgical removal was invariably curative in each case. Although infrequent, the possibility of tapeworm infection should be entertained in the evaluation of intracranial masses in patients who have visited exotic locales.

Adult↗

PubMed1990

Pituitary adenomas that produce adrenocorticotropic hormone and alpha-subunit: clinicopathological, immunohistochemical, ultrastructural, and immunoelectron microscopic studies in nine cases.

Eight surgical and one autopsy specimen of pituitary adenomas (six cases of Cushing's disease, two of Nelson's syndrome, and one of hypopituitarism) were studied by histochemical, immunohistocytological, and ultrastructural methods. Eight tumors showed the characteristic histochemical profile of corticotroph adenoma--amphophilic to basophilic, and periodic acid-Schiff-positive to some extent. In all tumors, immunohistochemical studies revealed adrenocorticotropic hormone (ACTH) and alpha-subunit in the cytoplasm of some adenoma cells. By electron microscopy, seven tumors were found to be monomorphous; six were typical corticotroph adenomas and one was a subtype II silent corticotroph adenoma. One unique lesion was bimorphous--i.e., composed of corticotrophs as well as cells resembling glycoprotein cells. Immunoelectron microscopy by the double-labeling immunogold technique, performed on one corticotroph adenoma, demonstrated the presence of ACTH and alpha-subunit not only within the same adenoma cells but also within the same secretory granules. The cytogenesis of ACTH alpha-subunit tumors, a rare form of plurihormonal adenoma, remains to be elucidated. The duration of disease associated with these tumors exceeded the duration in patients with ordinary corticotroph adenomas. Given the low frequency with which increases in serum alpha-subunit are detectable in patients with such tumors--13% in this series--hormone production is not recognized at preoperative evaluation.

Adenoma↗

PubMed1989

Evaluation of the glutamate antagonist dizocilipine maleate (MK-801) on neurologic outcome in a canine model of complete cerebral ischemia: correlation with hippocampal histopathology.

This study was designed to determine if dizocilipine maleate (MK-801), administered following 11 min of complete ischemia in dogs, could favorably alter neurologic outcome and hippocampal damage. Eighteen dogs were anesthetized and subjected to complete cerebral ischemia by temporary occlusion of the ascending aorta and the venae cavae via a thoracotomy. Five min postischemia, 9 dogs were given dizocilipine 150 micrograms/kg, followed by an infusion of 1.25 microgram/kg/min for 8 h. Control dogs were given equal volumes of placebo. Dogs were evaluated neurologically at 24, 48, and 72 h; thereafter, the brains were perfused, fixed and harvested. There was no significant difference in outcome between dizocilipine- and placebo-treated dogs: 5 of 9 given dizocilipine were normal, 1 was mildly injured and 3 were severely injured or dead. In the control animals given placebo, 3 of 9 were normal, 2 were mildly injured and 4 were moderately to severely injured. Histopathologic examination was limited to the hippocampus. CA1 and CA2,3,4 pyramidal neurons were graded according to degree of injury on a 5-point scale. There were no differences in histopathologic grades between the two groups. However, in both groups combined there was a significant correlation between neurologic outcome grade and histopathologic grade. The only notable systemic effect of dizocilipine appeared to be prolonged sedation which extended beyond 24 h postischemia but was not evident at 48 h postischemia. The authors conclude that more outcome studies in more sensitive models are needed.

Animals↗

PubMed1989

Clinicopathologic analysis of uterine malignant mixed müllerian tumors.

A clinicopathologic evaluation of 60 patients (median age, 66 years) presenting for primary treatment of uterine malignant mixed müllerian tumors between 1959 and 1982 was conducted. Surgical stage was utilized for assessment of survival by stage. With a minimum follow-up of 5 years, overall 2- and 5-year Kaplan-Meier survival estimates were 53 and 39%, respectively; they were 75 and 58% when disease was confined to the uterus and 27 and 15% when disease extended beyond the uterus. By log-rank and logit-rank analysis, surgical stage and depth of invasion stratified by stage were significant prognostic determinants; no significant association was found with carcinoma grade, sarcoma mitotic figure count, sarcoma histologic subtype, sarcoma necrosis, or capillary-like space involvement. No significant survival advantage was found for surgery plus irradiation or surgery plus chemotherapy compared with surgery alone after stratification according to stage. Progression-free survival after complete extirpation of macroscopic disease was not significantly different, stage for stage, between surgery alone and surgery plus radiotherapy.

Aged↗

PubMed1989

A cytogenetic study of 53 human gliomas.

Cytogenetic studies were performed on human glioma samples obtained by stereotactic biopsy, stereotactic craniotomy, or routine craniotomy. Using in situ culture and robotic harvesting techniques, we obtained suitable metaphases in 50 (94%) of 53 tumors, including 28 diffuse astrocytomas, four juvenile pilocytic astrocytomas, two gliosarcomas, three other miscellaneous astrocytomas, eight oligodendrogliomas, four mixed oligodendroglioma-astrocytomas, and four ependymomas. Cytogenetic studies were performed only on primary cultures; the mean culture time was 9.6 days (range 1-31 days). One or more chromosomally abnormal clones were observed in 35 (66%) tumors. Eleven (21%) other specimens had random nonclonal chromosome abnormalities. In four (8%) specimens, no chromosome abnormalities were noted. The results of this study suggest that grade 3 and 4 tumors are more likely to contain an abnormal clone than tumors of grade 1 or 2 (p less than 0.01). The most common numeric chromosome abnormalities were -6, +7, -10, -13, -14, -15, -18, and -Y. The most common structural abnormalities involved 1p, 6q, 7q, 8p, 9p, 11p, 11q, 13q, and 19q. Four tumors had two or more independent clones and ten contained subclones demonstrating karyotype evolution. With in situ culture and robotic harvesting techniques, cytogenetic studies can be successful on nearly all human gliomas, including those derived from small stereotactic biopsies.

Adolescent↗

PubMed1989

Postoperative radiotherapy of supratentorial low-grade gliomas.

Forty-nine patients with supratentorial low-grade gliomas underwent surgery (biopsy or subtotal resection) and postoperative radiotherapy at the Mayo Clinic between 1976 and 1983. The median, 5-, and 10-year overall survivals for the total group were 6.5 years, 62%, and 14%, respectively. Nine prognostic variables were examined for their possible association with survival, including age, sex, site, size, CT enhancement, histologic type, extent of resection, radiation volume, and radiation dose. Of these variables, only histologic type was significantly associated with survival. The estimated 5-year survival was 100% for the 5 patients with pilocytic astrocytomas, 83% for the 20 patients with oligodendrogliomas or mixed oligo-astrocytomas, and 40% in the 24 patients with ordinary astrocytomas (log rank p = 0.001). Other possible prognostic variables, such as radiation volume or total dose, showed no association with survival. Twenty-seven patients had a documented treatment failure. For the 20 patients in whom the pattern of failure could be determined, all failed within their radiation portals. Eleven patients had additional tissue obtained following suspected disease recurrence. Tumor was found in ten of these patients, and radionecrosis in one.

Adolescent↗