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Richard A Prayson

Publications and source records attributed to Richard A Prayson.

At least 37 records · Page 2Linked to original sources
PubMed2005

Epidermal growth factor receptor amplification does not have prognostic significance in patients with glioblastoma multiforme.

PURPOSE: There have been conflicting reports in the literature regarding the prognostic significance of epidermal growth factor receptor (EGFR) amplification in patients with glioblastoma multiforme (GBM). The purpose of this study is to determine the prognostic significance of EGFR amplification in patients with GBM treated at the Cleveland Clinic Foundation. METHODS AND MATERIALS: A retrospective review of GBM patients treated with surgery at the Cleveland Clinic Foundation was performed. Amplification of EGFR was evaluated with fluorescence in situ hybridization in a total of 107 patients diagnosed between December 1995 and May 2003. In addition to EGFR status, various prognostic factors were evaluated to determine the factors that influenced survival and radiographic response rate. The median follow-up was 9 months. RESULTS: The overall median survival was 9.8 months, with a 1-year survival of 40%. Of the 107 patients in whom EGFR status was evaluated, 36 (33.6%) were found to have EGFR amplification. On multivariate analysis, median survival was found to be significantly improved for patients with age < 60 (12.6 months vs. 8 months, p = 0.0061), patients with Karnofsky Performance Status > or = 70 (12.1 months vs. 4.4 months, p < 0.0001), patients who had undergone subtotal resection or gross total resection (11.1 months vs. 4.1 months, p = 0.002), and patients who received a radiation dose > or = 60 Gy compared with no radiation (12.7 months vs. 3 months, p < 0.0001). There was no association of EGFR amplification with survival. When stratified by age (< 60 vs. > or = 60), EGFR status still did not reach statistical significance in predicting for survival. For the 81 patients who had radiographic follow-up, the 1-year overall local control was 14%. On univariate analysis, only treatment with radiation (< 60 Gy vs. > or = 60 Gy vs. no radiation, p = 0.03) was found to predict for improved local control. Treatment with radiation did not remain statistically significant on multivariate analysis. CONCLUSION: Epidermal growth factor receptor amplification was not found to be a significant prognostic indicator of overall survival or radiographic local control in patients with GBM treated with surgery at the Cleveland Clinic Foundation. Further studies are needed to fully delineate the significance of this molecular marker in patients with GBM.

Adult↗
PubMed2005

Optic nerve choristoma.

Choristomas are rare lesions that typically involve peripheral nerves and are marked by the presence of histologically normal tissue for an organ or body part other than the site at which it is located. Reports of choristoma involving cranial nerves are extraordinarily rare. We report a case of an optic nerve choristoma arising in a 24-year-old woman. The lesion was marked by a disordered admixture of smooth muscle tissue and optic nerve tissue. The literature on optic nerve choristoma is reviewed.

Actins↗
PubMed2005

Fascin expression in 90 patients with glioblastoma multiforme.

Fascin is a protein that serves to aggregate F actin into bundles that rearrange the cytoskeleton and promote cellular motility. Fascin has been linked to the invasive behavior of some tumors. Fascin immunohistochemical analysis was performed in 90 glioblastoma multiforme, including 53 males and 37 females (mean age, 58.3 years). All patients had tumors that demonstrated positive fascin staining. Nineteen tumors showed more than 75% positive staining tumor cells, 14 tumors had more than 50% to 75% staining, 23 tumors had more than 25% to 50% staining, 26 tumors had more than 5% to 25% staining, and 8 tumors had less than 5% staining. In comparison, 9 of 11 low-grade astrocytomas had 50% or less staining for fascin. Eight of 10 anaplastic astrocytomas had more than 50% fascin staining. All gliomas studied expressed fascin by immunohistochemistry. Higher grade tumors generally expressed a greater degree of fascin staining. There was no obvious correlation with the extent of staining and survival among glioblastoma multiforme. Fascin may play a role in tumor cell infiltration.

Adolescent↗
PubMed2005

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue arising in the lateral ventricle.

Extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) lymphomas are a well-described type of low-grade B-cell non-Hodgkin lymphoma. They typically arise adjacent to mucosal surfaces in the gastrointestinal tract, lung and conjunctiva, and, less frequently, in the skin, salivary gland and thyroid gland. Unusual locations, such as the genitourinary tract, thymus and meninges, have also been reported. We recently encountered a case of an intracranial MALT lymphoma in a 53-year-old man who presented with persistent headaches and a seizure. The lesion developed as a mass within the lateral ventricle, appeared to be arising from the choroid plexus, and was not associated with meninges. Histologically, there was a vaguely nodular, dense lymphoid infiltrate with occasional benign follicles colonized by marginal zone lymphoma, suggesting derivation from a focus of prior inflammation. Translocations involving the MALT1 gene were not identified but karyotypic evaluation highlighted a complex cytogenetic profile with many chromosomal abnormalities. This rare case provides insight into the pathophysiology of MALT lymphomas.

Adult↗
PubMed2005

Monomorphous angiocentric glioma: a distinctive epileptogenic neoplasm with features of infiltrating astrocytoma and ependymoma.

We present 8 examples of a neoplasm with features of both astrocytoma and ependymoma that may represent a distinct clinicopathologic entity. The cerebral hemispheric tumors occurred in patients that were 3, 4, 12, 14, 15, 26, 30, and 37 years of age. All presented with seizures that, with the exception of 2, began in childhood. Magnetic resonance imaging studies showed ill-defined, T2-hyperintense, generally noncontrast-enhancing lesions that, although centered on the cortex or amygdala, extended into the underlying white matter for a short distance. Histologically, the variably infiltrative tumors were distinctively angiocentric with well-developed perivascular pseudorosettes in some cases. Longitudinal and/or circumferential orientations of perivascular cells were common also. The cells were uniform in their cytologic features from case to case and were bipolar in all but one case. A glial nature was inferred from immunoreactivity for GFAP, and ependymal differentiation was suggested by positivity for EMA in three cases and ultrastructural features in one. Overall, the tumors were biologically indolent except for one that recurred and ultimately proved fatal.

Adolescent↗
PubMed2005

The utility of MIB-1/Ki-67 immunostaining in the evaluation of central nervous system neoplasms.

The diagnosis and assignment of grade in neoplasms of the central nervous system (CNS), for the most part, are morphologically based and predicated on the interpretation of descriptions of what the phenotypic findings are for a particular tumor type. Not surprisingly, the application of various grading systems in CNS neoplasia has been limited somewhat by interobserver variability. Since assignment of grade and tumor type is the basis upon which therapeutic intervention is grounded, investigators have been searching for ancillary means by which morphologically based systems can be improved. Utilization of cell proliferation markers in the evaluation of tumors can be potentially useful in this endeavor. This review focuses on issues surrounding the utilization of MIB-1 or Ki-67 antibody in the evaluation of CNS neoplasms.

Antibodies, Antinuclear↗
PubMed2005

Molecular diagnostic techniques for the clinical evaluation of gliomas.

Newly developed molecular techniques have been integrated into the routine assessment of gliomas in some laboratories. These tests serve to complement the subjective nature of morphologic analysis. Such strategies add useful information regarding pathogenicity, patient survival, and potential response to treatment. As we learn more about the molecular characteristics of these tumors, this information will provide the basis for the development of specific, targeted therapies. This review will describe the background, methods, clinical utility, and strengths and weaknesses of several molecular approaches, including fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), loss of heterozygosity (LOH)-testing, and nucleic acid sequencing, that are currently being employed in the diagnosis and evaluation of glial tumors.

Base Sequence↗
PubMed2005

Insights into meningioangiomatosis with and without meningioma: a clinicopathologic and genetic series of 24 cases with review of the literature.

Meningioangiomatosis (MA) is a rare seizure-associated lesion of presumed hamartomatous or developmental origin. It is occasionally combined with a neoplasm, most commonly meningioma (MA-M). In the current study, we examined 24 cases (14 pure MA, 10 MA-M) using immunohistochemistry for merlin, protein 4.1 B, progesterone receptor (PR), and MIB-1, as well as FISH for NF2 and 4.1B gene dosages. Nine cases of MA-M (90%) had gene deletions (NF2/4.7B), protein losses (merlin/protein 4.1B), and/or PR positivity, with a similar or identical phenotype in both components. No PR positivity or gene deletions were seen in pure MAs, though merlin and/or protein 4.1B were immunonegative in six cases. Our data suggest that in most MA-Ms, the MA component is neoplastic, likely representing an exuberant perivascular pattern of spread from the meningioma, rather than an underlying hamartoma. This pattern of spread may be facilitated by meningiomas that are predominantly leptomeningeal or intracerebral in origin. It remains important to distinguish this pattern from true brain invasion, given the more ominous prognostic significance of the latter. In contrast, most perivascular spindled cells of pure MA are genetically and immunohistochemically similar to non-neoplastic meningothelial cells, consistent with current histogenetic theories.

Adolescent↗
PubMed2005

Surgical management of osseous hemangioblastoma of the thoracic spine: technical case report.

OBJECTIVE AND IMPORTANCE: Spinal hemangioblastomas usually occur as isolated, intramedullary, central nervous system masses, often as a component of von Hippel-Lindau syndrome. They may occasionally occur extradurally and give the appearance of vertebral hemangioma. Rarely, they may be purely osseous lesions. The surgical management of these lesions has not been elaborated. We present a case and discuss the management of multilevel osseous hemangioblastoma of the thoracic spine. CLINICAL PRESENTATION: A 50-year-old woman with a history of thoracic hemangioblastoma 3 years earlier presented with progressive paraparesis. Imaging revealed circumferential tumor involvement of T7 to T9, inclusive. There was severe spinal cord compression. INTERVENTION: The patient underwent surgery via a bilateral lateral extracavitary approach to the tumor. This permitted a complete spondylectomy of T7, T8, and T9; complete tumor removal; and decompression of the spinal cord. Pathological analysis confirmed hemangioblastoma. The spine was reconstructed with an interbody expandable cage and pedicle screw fixation, all placed via the dorsal approach. The patient improved neurologically after the operation. CONCLUSION: Although extremely rare, hemangioblastomas may occur in a purely osseous location. They may resemble vertebral hemangioma. Treatment should include aggressive surgical removal, although arduous, if appropriate. A bilateral lateral extracavitary approach is ideal for complete spondylectomy. With this technique, ventral and dorsal reconstruction of the spine through the same incision is possible.

Female↗
PubMed2005

Optical coherence tomography: a new method to assess aneurysm healing.

OBJECT: Aneurysmal subarachnoid hemorrhage affects approximately 10/100,000 people per year. Endovascular coil embolization is used increasingly to treat cerebral aneurysms and its safety and durability is rapidly developing. The long-term durability of coil embolization of cerebral aneurysms remains in question; patients treated using this modality require multiple follow-up angiography studies and occasional repeated treatments. METHODS: Optical coherence tomography (OCT) is an emerging imaging modality that uses backscattered light to produce high-resolution tomography of optically accessible biological tissues such as the eye, luminal surface of blood vessels, and gastrointestinal tract. Vascular OCT probes in the form of imaging microwires are presently available--although not Food and Drug Administration-approved--and may be adapted for use in the cerebral circulation. In this study the authors describe the initial use of OCT to make visible the neck of aneurysms created in a canine model and treated with coil embolization. Optical coherence tomography images demonstrate changes that correlate with the histological findings of healing at the aneurysm neck and thus may be capable of demonstrating human cerebral aneurysm healing. CONCLUSIONS: Optical coherence tomography may obviate the need for subsequent follow-up angiography studies as well as aid in the understanding of endovascular tissue healing. Data in this study demonstrate that further investigation of in vivo imaging with such probes is warranted.

Animals↗
PubMed2005

Fatal West Nile Virus infection after rituximab/fludarabine--induced remission for non-Hodgkin's lymphoma.

West Nile virus (WNV) infections are potentially life threatening in immunocompromised hosts. Currently, the best diagnostic test is serology. Reverse-transcriptase polymerase chain reaction (RT-PCR) testing has a role, but, because WNV is a cell-associated neurotropic virus, RT-PCR results are frequently negative even in cases of active infection. We present a case in which serology results were persistently negative because the patient was immunocompromised following lymphoma treatment. The role of humoral immunity in resolution of WNV is also discussed.

Antibodies, Monoclonal↗
PubMed2005

Bovine spongiform encephalopathy and variant Creutzfeldt-Jakob disease: how safe is eating beef?

Cases of bovine spongiform encephalopathy (BSE, mad cow disease) have been found in North American cattle. Its human counterpart, called variant Creutzfeldt-Jakob disease (variant CJD), is rare but seems to be linked to eating diseased beef. Many questions remain about these diseases, such as why young people seem at greater risk of variant CJD. Also, are some people more genetically at risk for acquiring variant CJD than others?

Age Factors↗
PubMed2005

Immunohistochemical expression of cyclooxygenase 2 in follicular carcinomas of the thyroid.

CONTEXT: Cyclooxygenase 2 (COX-2) has been shown to be up-regulated and/or overexpressed in a variety of human neoplasms. However, limited data exist on the role of COX-2 in follicular carcinomas of the thyroid. Studies in this area are potentially significant, since therapeutic agents that inhibit COX-2 are currently available and could play a role in treatment. DESIGN: A retrospective clinicopathologic review with COX-2 immunohistochemical staining of 34 follicular carcinomas and 7 follicular adenomas with incomplete capsular penetration was performed. RESULTS: The study included 41 patients (25 women; mean age, 50.9 years). All patients underwent gross total resection of the neoplasm. Fifteen carcinoma patients received adjuvant radiotherapy. Seven patients with follicular carcinomas developed recurrent disease: 3 patients were alive (mean follow-up, 10.1 years) and 4 patients died of metastatic disease (mean follow-up, 3.5 years). All remaining patients were disease free (mean follow-up, 5.9 years). Only 1 follicular adenoma with incomplete capsular penetration recurred (patient alive at 9 years). The remaining patients were disease free (mean follow-up, 4.9 years). The COX-2 staining was positive in 11 tumors (9 of 34 follicular carcinomas, 2 of 7 follicular adenomas with incomplete capsular penetration). A greater percentage of recurrences (36% COX-2 positive vs 13% COX-2 negative) and fatal tumors (18% COX-2 positive vs 7% COX-2 negative) occurred in patients who had COX-2-positive staining neoplasms. CONCLUSION: Only a few follicular carcinomas (26%) and follicular adenomas with incomplete capsular penetration (29%) express COX-2 by immunohistochemical analysis. The data suggest that such expression of COX-2 may correlate with increased tumor recurrence and death; however, studies with larger numbers of patients will be needed to establish this.

Adenocarcinoma, Follicular↗
PubMed2005

West Nile virus meningoencephalitis: MR imaging findings.

BACKGROUND AND PURPOSE: Reports of MR imaging in West Nile virus (WNV) meningoencephalomyelitis are few and the described findings limited. The purpose of this study was to review the spectrum of MR imaging findings for WNV meningoencephalomyelitis and investigate whether any of the findings correlates with clinical presentation of flaccid paralysis. METHODS: We reviewed the MR imaging findings of 17 patients with confirmed WNV encephalitis and/or myelitis. MR imaging brain studies were evaluated for location of signal intensity abnormalities, edema, hydrocephalus, or abnormal enhancement. MR imaging spine studies were evaluated for signal intensity abnormalities in cord and/or enhancement. RESULTS: Retrospective review of the MR imaging studies of 17 patients was performed by 2 neuroradiologists. Eleven of 16 brain MR images demonstrated abnormalities. Eight (50%) patients had abnormal studies related to meningoencephalitis. All 8 patients had abnormal findings in the deep gray matter and/or brain stem; 2 had additional white matter abnormalities. Three patients with abnormal MR studies of the spine had extremity weakness on examination. The imaging findings included abnormal signal intensity more pronounced in the ventral horns and/or enhancement around the conus medullaris and cauda equina. One patient had additional abnormalities in the pons. CONCLUSION: Abnormal MR imaging findings in patients with WNV meningoencephalomyelitis are nonspecific but not uncommon. Anatomic areas commonly affected are basal ganglia, thalami, mesial temporal structures, brain stem, and cerebellum. Extremity weakness or flaccid paralysis corresponds to spinal cord/cauda equina abnormalities.

Adult↗
PubMed2004

Pituicytoma.

Pituicytoma is a rare, low-grade neoplasm that originates in the neurohypophysis of the pituitary gland. We report the clinicopathologic features of a pituicytoma arising in a 52-year-old man who presented with a mass and panhypopituitarism, clinically suggestive of a pituitary adenoma. The tumor was marked by a proliferation of elongated cells arranged in bundles and interlacing fascicles. The tumor demonstrated positive staining with S-100 protein and glial fibrillary acid protein antibodies. The tumor did not stain with antibodies to cytokeratin, synaptophysin, chromogranin, anterior pituitary hormones, or p53. An MIB-1 labeling index of 1.1% was observed. The tumor was subtotally resected and recurred 11 months after the initial surgery. The literature on this rare tumor will be reviewed and differential diagnosis discussed.

Biomarkers, Tumor↗
PubMed2004

Cyclooxygenase-2, Bcl-2, and chromosome 1p analysis in protoplasmic astrocytomas.

Protoplasmic astrocytomas are rare gliomas whose nosology remains enigmatic. This study retrospectively reviews the clinicopathologic features of eight tumors, including evaluation of these neoplasms for chromosome 1p loss, Bcl-2 immunoreactivity, and cyclooxygenase-2 immunoreactivity. Patients ranged in age from 3 to 49 years (median 25.5 years) and included six males and two females. All patients presented with a period of seizures (median duration of period, 54 months) before surgery. Five tumors were either totally or partially based in the temporal lobe. In the six patients for whom follow-up information was available, there was no evidence of recurrence at last known follow-up (range 5 to 171 months; median 134 months). Histologically, all tumors were marked by a proliferation of cells with rounded to oval nuclear contours and a paucity of cytoplasmic processes, arranged against a microcystic background. A rare mitotic figure was observed in only one tumor. Vascular proliferative changes and necrosis were not seen in any of the tumors. None of the tumors showed allelic loss on chromosome 1p by fluorescent in situ hybridization (FISH) analysis. Cyclooxygenase-2 (an enzyme involved in the conversion of arachidonate to prostaglandin H2 and G2) immunoreactivity was observed in two tumors. Bcl-2 (an anti-apoptotic protein) immunoreactivity was also confined to two tumors. In conclusion, protoplasmic astrocytomas appear to be low-grade neoplasms, as evidenced by their relatively benign clinical course. Although they histologically resemble microcystic oligodendrogliomas, none of the tumors showed allelic loss on chromosome 1p, a finding that has been described in the majority of low-grade oligodendrogliomas. This suggests that the protoplasmic astrocytoma is a distinct entity from low-grade oligodendroglioma. Similar to other low-grade astrocytomas, only a minority of tumors show evidence of cyclooxygenase-2 and Bcl-2 immunoreactivity.

Adult↗
PubMed2004

Clinicopathologic findings in patients with infantile hemiparesis and epilepsy.

Infantile hemiparesis may be associated with significant morbidity and may have a profound impact on a child's physical and social development. There are little published data evaluating the clinicopathologic features of patients with infantile hemiparesis. The present study retrospectively examines these clinicopathologic features in a surgical series of 21 patients with infantile hemiparesis. The study group was comprised of 21 patients, 13 females and 8 males, ranging in age from 5 to 41 years (mean, 20 years) at the time of surgery. Hemiparesis involved the right side in 16 patients and the left side in 5 patients. Imaging studies identified porencephaly in 8 patients (38%), encephalomalacia in 5 patients (24%), focal cerebral atrophy in 9 patients (43%), ventricular dilatation in 6 patients (29%), and white matter hyperintensities in 4 patients (19%). Concomitant neurologic diseases included medically intractable epilepsy in all 21 patients and visual field defects in 11 patients (52%). Significant perinatal history included prematurity in 7 patients (33%) and cesarean section, forceps delivery, placental abruption, fetal distress, and prolonged rupture of membranes each in 1 patient (5%). The remainder of the patients had an uncomplicated perinatal course (43%). Twelve patients underwent functional hemispherectomy (57%), 8 patients underwent lobectomy (38%) and 1 patient underwent "cyst" resection (5%). Histological evaluation demonstrated lesional (corresponding to radiographic findings) tissue in 15 of the 21 cases (71%). Infarction, malformations due to abnormalities of cortical development (cortical dysplasia) and gliosis with microcalcifications were each found in 6 patients (29%). Infarction and a geographically distinct area of cortical dysplasia were found to coexist in 1 case. Histopathologic findings in the 6 cases in which excised tissue was considered nonlesional included gliosis in all 6 of the cases, hippocampal sclerosis in 2 cases (10%), and neuronal heterotopia in 2 cases (10%). An osteoma was identified in 1 patient. The most common pathological findings observed in our series were infarction and cortical dysplasia, although radiographically, infarct-related changes were the most evident. Hippocampal sclerosis was encountered in 2 patients, suggesting that a subset of cortical dysplasias and hippocampal sclerosis may be caused by an in utero ischemic event.

Adolescent↗