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PubMed1983

Nuclear magnetic resonance (NMR) imaging of tumors in the posterior fossa.

Nuclear magnetic resonance (NMR) images were obtained in 12 patients with mass lesions in the posterior fossa and the results compared with X-ray computed tomography (CT). Inversion recovery T1-weighted images demonstrated abnormalities in six of six intrinsic lesions and three of six extrinsic lesions. Spin echo T2-weighted images demonstrated abnormalities in two of two intrinsic lesions and four of five extrinsic lesions. Saturation recovery T1-weighted images were normal in two of two intrinsic lesions and two of four extrinsic lesions. Overall, NMR detected 11 of 12 lesions. Two intrinsic tumors detected by NMR were not detected by CT evaluation. Two small extrinsic tumors required CT gas cisternography for detection.

Astrocytoma↗
PubMed1987

Distribution of type VI collagen in human gliomas: comparison with fibronectin and glioma-mesenchymal matrix glycoprotein.

The distribution of type VI collagen was examined immunohistochemically in normal tissues and in 24 human gliomas and six medulloblastomas. Its localization in the neoplasms was compared with that of fibronectin and glioma-mesenchymal extracellular matrix (GMEM) glycoprotein. In normal non-neural tissues type VI collagen was demonstrated in the interstitial connective tissue and in some basement membranes. In normal brain it was localized to the vasculature, leptomeninges, and pial-glial membrane. In neoplasms type VI collagen and fibronectin codistributed in the vasculature and stromal connective tissue. The GMEM glycoprotein, as identified by monoclonal antibody (MAb) 81C6, and a related glioma-mesenchymal matrix antigen identified by MAb 2A6, were expressed not only in the tumor vasculature and connective tissue, but also within the tumor parenchyma in association with glioma cells. The staining intensity was variable in 20 malignant gliomas and weak to absent in two pilocytic astrocytomas and six medulloblastomas. An oligodendroglioma and ependymoma both expressed the 2A6 epitope, but staining with MAb 81C6 was weak to absent. The antigens identified by MAb 81C6 and MAb 2A6 represent the only recognized extracellular matrix components, other than proteoglycans, that are associated with glioma cells in vivo. As prominent constituents of the pericellular matrix, they may be involved in recognized matrix functions such as the modulation of cell adhesion and migration.

Animals↗
PubMed1996

Expression of growth factors and growth factor receptors in capillary hemangioblastoma.

To elucidate the mechanisms underlying the regulation of growth and differentiation of capillary hemangioblastoma we studied the expression of selected growth factors and growth factor receptors by immunocytochemistry. As stromal cells of capillary hemangioblastoma express high levels of vascular endothelial growth factor (VEGF) and placental growth factor (P1GF) mRNA, we studied the distribution of the corresponding VEGF and P1GF proteins. We also studied the expression of epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptors (PDGFR) because their ligands have been reported to promote angiogenesis. The stromal cells expressed abundant EGFR and, in addition, some stromal cells expressed PDGFR-alpha but not PDGFR-beta. In contrast, the endothelial cells co-expressed PDGFR-alpha and PDGFR-beta. VEGF and P1GF were expressed by scattered stromal cells; however, more intense staining was observed in the endothelial cells of the intratumoral blood vessels, possibly indicating the secreted growth factors bound to their target receptors. We conclude that capillary hemangioblastomas express a variety of growth factor receptors and ligands, potentially involved in both autocrine and paracrine loops. The uniformly high EGFR expression is unique among brain tumors and may be associated with the typical morphology of capillary hemangioblastoma. The expression of highly angiogenic growth factors and their receptors may contribute to the rich vascularity of this enigmatic tumor.

Adult↗
PubMed1999

Clinical significance of rebound nystagmus.

OBJECTIVE/HYPOTHESIS: Magnetic resonance imaging (MRI) examination is performed in cases of rebound nystagmus to elucidate the responsible site for rebound nystagmus. METHODS: Patients with vertigo or tinnitus received a battery of audiological and neuro-otological tests. Those who had rebound nystagmus were rechecked by electronystagmography and examined by MRI. RESULTS: Ten patients had a second-degree nystagmus evoked by changing direction of fixation, from the lateral to the forward gaze. All patients displayed positive MRI findings in cerebellum or brainstem, including tumor in seven cases and stroke in three cases. Moreover, in seven of eight cases with unilateral lesions, rebound nystagmus was ipsilateral with respect to the side of the lesion. CONCLUSION: Rebound nystagmus implies a lesion in cerebellum or brainstem for which MRI examination is 100% sensitive. It has a certain lateralizing value, with its direction away from the lesioned side.

Adolescent↗
PubMed1990

A case of dyschondroplasia associated with brain stem glioma: diagnosis by stereotactic biopsy.

We present a 24-year-old patient with multiple chondromas of both hands, the pelvis, the left leg, and an associated brain stem glioma. There was no evidence of hemangioma or dyschromia, and the condition was diagnosed as Ollier's disease, a special type of dyschondroplasia like Maffucci's syndrome and Kast's disease. An increased overall risk for development of malignant skeletal and nonskeletal tumors is associated with Maffucci's syndrome. The risk of malignant degeneration is lower in Ollier's disease. A glioma in the pons and the right lobe of the cerebellum was found in this patient. The literature describes an association with gliomas in only 12 cases of dyschondroplasia and an infratentorial localization in just one case. Signs of malignancy were histologically confirmed in 7 cases without significant preponderance of any one type. Our patient had a low-grade brain stem astrocytoma with fibrillar and gemistocytic components. A stereotactic serial biopsy made it possible to rule out malignant degeneration. Stereotactic brain tumor biopsy as a routine neurosurgical procedure is particularly valuable for deep space-occupying processes and forms the basis for therapy. In the present case, irradiation was not recommended.

Adult↗
PubMed2000

Correlation of neurosurgical subspecialization with outcomes in children with malignant brain tumors.

OBJECTIVE: This study was performed to evaluate the association between the type of neurosurgeon (general or pediatric) and either the extent of tumor removal or the frequency of complications in children undergoing malignant brain tumor resections. METHODS: Data were analyzed from three recent Children's Cancer Group studies: two on medulloblastomas/primitive neuroectodermal tumors and one on malignant gliomas. Neurosurgeons were classified as general neurosurgeons, as designated pediatric neurosurgeons in their institutions, or as members of the American Society of Pediatric Neurosurgeons (ASPN), which requires pediatric neurosurgical experience and practice standards. RESULTS: Data forms from 732 children were analyzed; 485 were from children with medulloblastomas/primitive neuroectodermal tumors, and 247 were from children with malignant gliomas. Operations were performed by 269 neurosurgeons, including 213 general neurosurgeons, 29 designated pediatric neurosurgeons, and 27 ASPN members. The mean number of operations per surgeon was 1.8, 4.9, and 7.6 for general neurosurgeons, designated pediatric neurosurgeons, and ASPN members, respectively. There was a significant relationship between the extent of tumor resection or the amount of residual tumor and the type of neurosurgeon. Designated pediatric neurosurgeons and ASPN members were more likely to remove more than 90% of the tumor and to leave less than 1.5 cc of residual tumor than were general neurosurgeons (P<0.05). In these studies, the probability of extensive tumor removal correlated with the number of operations the neurosurgeon performed (P<0.01). Neurological complications occurred in the following proportion of cases: general neurosurgeons, 23%; designated pediatric neurosurgeons, 32%; and ASPN members, 18%. CONCLUSION: Pediatric neurosurgeons are more likely than general neurosurgeons to extensively remove malignant pediatric brain tumors. In these tumors, extent of removal has been demonstrated to influence survival.

Brain Neoplasms↗
PubMed2000

Molecular insight into medulloblastoma and central nervous system primitive neuroectodermal tumor biology from hereditary syndromes: a review.

Through the study of uncommon familial syndromes, physicians and scientists have been able to illuminate the underlying mechanisms of some of the more common sporadic diseases; this is illustrated best by studies of familial retinoblastoma. A number of rare familial syndromes have been described in which affected individuals are at increased risk of developing medulloblastoma and/or supratentorial primitive neuroectodermal tumors. The descriptions of many of these syndromes are based on patients observed by clinicians in their clinical practice. Determination of the underlying genetic defects in these patients with uncommon syndromes has led to identification of a number of genes subsequently found to be mutated in sporadic medulloblastomas (tumor suppressor genes). Associated genes in the same signaling pathways have also been found to be abnormal in sporadic medulloblastoma. Identification of patients with these rare syndromes is important, as they are often at increased risk for additional neoplasms, as are family members and future children. We review the published literature describing hereditary syndromes that have been associated with an increased incidence of medulloblastoma and/or central nervous system primitive neuroectodermal tumor. Review of the underlying molecular abnormalities in comparison to changes found in sporadic neoplasms suggests pathways important for tumorigenesis.

Central Nervous System Neoplasms↗
PubMed1977

Brain tumors of mixed tissue origin: staining procedures to distinguish glial from connective tissue.

Described is a unique mixed intracerebral tumor composed of schwannoma, piloid astrocytoma, and angiomatous malformation. Review of conventional staining methods for distinguishing glial from connective tissue fibrils reveals that Mallory's phosphotungstic acid-hematoxylin (PTAH) method is less specific than is generally recognized. Knowledge of these pitfalls, combined with use of hematoxylin and eosin stains, and reticulum impregnations are currently most useful in making the distinction by light microscopy. Criteria for malignancy of schwannoma and other mesenchymal tumors should be based on number of mitotic figures and invasiveness rather than on pleomorphiam of cells. Prior knowledge of the location of the tumor may lead to diagnosing some schwannomas as other types of tumor.

Adult↗
PubMed1988

Intracerebral and intracerebellar neurilemoma.

Neurilemomas (schwannomas) within the brain substance and not associated with a peripheral nerve are rare. We have presented two such cases, one with a prominent angiomatous component. Neither patient had neurofibromatosis. Both patients had headache and focal neurologic signs, and surgical excision was curative in both cases.

Adult↗
PubMed1997

Childhood tumors.

Advances are slowly being made in the understanding and treatment of primary childhood brain tumors. The addition of chemotherapy has resulted in better survival for children with medulloblastoma. For other tumor types, therapeutic advances have been slower. High-dose chemotherapy is increasingly being employed to treat malignant childhood tumors, with variable results. Chemotherapy has been effective in low-grade glial tumors.

Antineoplastic Agents↗
PubMedDate not supplied

Intracranial germ cell tumors in children with and without Down syndrome.

PURPOSE: Two Chinese children with Down syndrome affected by intracranial germ cell tumors are described. Because they represent two of eight affected patients in the current series from 1990 to 1996, it is postulated that such occurrence may be more than a coincidental event. PATIENTS AND METHODS: Two children with Down syndrome developed germ cell tumors in atypical intracranial sites that affected basal ganglion and cerebellum. The pathology showed germinoma and yolk sac tumor, respectively. These were treated by radical surgical resection and chemotherapy with cisplatin, etoposide, and bleomycin, but without radiotherapy. RESULTS: One patient survived 3 years without radiologic evidence of tumor. The other died from infective complications caused by severe myelosuppression after chemotherapy. CONCLUSIONS: Subtle neurologic manifestations in developmentally handicapped patients with intracranial space-occupying lesions could result in delayed diagnosis. Children with Down syndrome suffering from brain tumors may have a higher chance for germ cell tumors. Assay for alpha-fetoprotein and beta-human chorionic gonadotrophin could hasten diagnosis in some cases. This observation and review of literature suggest an increased risk of developing intracranial germ cell tumors in subjects with Down syndrome.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Abundance of apoptotic neoplastic cells in diagnostic biopsy samples is not a prognostic factor in childhood primitive neuroectodermal tumors of the central nervous system.

PURPOSE: To assess if the abundance of apoptotic tumor cells is an independent prognostic factor in primitive neuroectodermal tumors (PNET) of the central nervous system. PATIENTS AND METHODS: Formalin-fixed paraffin-embedded tumor tissue sections from 78 clinically well-characterized children with PNET were evaluated by terminal deoxytransferase-mediated deoxyuridinie-5'-triphosphate (dUTP) nick-end labeling (TUNEL). Apoptotic indices (AI) were determined by counting TUNEL-positive tumor cells either in the highest staining region (AI hot spot) or in at least 15 randomly chosen fields (AI random). The AI hot spot and AI random were then correlated with clinical variables and survival outcome. RESULTS: AI hot spot (median 0.56%; range 0%-6.54%) and AI random (median 0.30%; range 0%-3.21%) showed considerable intertumor variability. Moreover, 53% of the evaluated PNET showed a more than two-fold difference between AI hot spot and AI random, showing important intratumoral variability of the abundance of apoptotic cells in a subset of the evaluated PNET. No significant associations were found between AI hot spot and AI random with clinical variables or survival outcome. CONCLUSION: The apoptotic index does not predict survival outcome and is not specifically associated with clinical variables of prognostic significance in childhood PNET.

Apoptosis↗
PubMed2001

Primary malignant melanoma of the cerebellopontine angle.

BACKGROUND: Malignant tumors of the cerebellopontine angle are very rare, accounting for less than 1% of lesions at this site. These may be primary or secondary tumors of the temporal bone, central nervous system (CNS), or leptomeninges. Malignant melanoma is uncommon, accounting for 1.5% of all types of malignant tumors. Metastatic melanoma is a frequent cause of CNS metastasis, often with leptomeningeal spread. Primary leptomeningeal melanoma is, however, rare and even more so at the cerebellopontine angle. The prognosis for CNS malignant melanoma is generally very poor. PATIENT: The authors describe the case of a 29-year-old woman with unilateral hearing loss and facial paresis. Magnetic resonance imaging (MRI) demonstrated a mass that was thought to be an acoustic neuroma but was seen to involve the cochlea as well as the internal auditory meatus and cerebellopontine angle. The lesion was subsequently excised completely by a trans-labyrinthine approach, with facial nerve preservation, and was shown on histologic examination to be a malignant melanoma. Further comprehensive investigation did not reveal a primary extracranial site or any sign of CNS spread. The clinical features of this case, including the radiologic and histologic findings, are described, and literature concerning management is reviewed.

Adult↗
PubMed2002

Differentiation between cerebellopontine angle tumors in cancer patients.

OBJECTIVE: The possibility of metastasis to the cerebellopontine angle should be considered when a cancer patient has inner ear-related symptoms, although such metastasis is rare. Distinguishing between an independent tumor and a metastasis presents a challenge to the clinician once magnetic resonance imaging reveals a space-occupying lesion in the cerebellopontine angle. This study attempted to differentiate between primary benign and metastatic malignant cerebellopontine angle tumors in cancer patients. SETTING: University hospital. PATIENTS: A total of 174 cancer patients with inner ear-related symptoms such as vertigo, hearing loss, or tinnitus were seen at the university hospital from January 1994 to December 2000. All patients underwent a battery of audiologic and neurotologic tests. Magnetic resonance imaging was performed either when the clinical presentation suggested vertigo of central origin or when sensorineural hearing loss developed. RESULTS: Magnetic resonance imaging confirmed tumors of the cerebellopontine angle in 6 (3%) of the 174 patients, including 3 men and 3 women. Their ages ranged from 46 to 80 years (mean 62 years). The final diagnoses were breast cancer with cerebellopontine angle metastasis (1), breast cancer with cerebellopontine angle epidermoid cyst (1), colon cancer with cerebellopontine angle metastasis (1), colon cancer with acoustic neuroma (1), nasopharyngeal carcinoma with cerebellopontine angle metastasis (1), and nasopharyngeal carcinoma with cerebellopontine angle benign tumor (1). CONCLUSIONS: When a cerebellopontine angle tumor is discovered in a cancer patient, metastatic cancer should be suspected when the tumor presents with deficits of the VIIth and VIIIth cranial nerves of rapid progression or bilateral involvement, or extracranial systemic metastasis. Laboratory examinations such as cytologic study of the cerebrospinal fluid and serologic study can assist in the diagnosis.

Aged↗
PubMed2003

Donors with central nervous system malignancies: are they truly safe?

BACKGROUND: In an era of organ shortage, the use of expanded or marginal donors has been attempted to increase transplantation rates and diminish waiting list mortality. One strategy is the use of organs from patients with a history of or active central nervous system (CNS) tumor. METHODS: Sixty-two recipients were identified as the recipients of organs from donors with a history of or active CNS malignancy. Patient demographics, donor tumor management, incidence of tumor transmission, and patient survival were examined. RESULTS: Of the organs recovered and transplanted from donors with astrocytoma, 14 were associated with at least one risk factor including high-grade tumor (n=4), prior surgery (n=5), radiation therapy (n=4), and systemic chemotherapy (n=4). One tumor transmission was identified at 20 months posttransplant with the patient expiring from metastatic disease. Twenty-six organs were transplanted from glioblastoma patients with 15 demonstrating risk factors including high-grade tumor (n=9) and prior surgery (n=10). Eight transmissions were identified with a range of 2 to 15 months posttransplant, with seven patients dying as the result of metastatic disease. Seven organs were used from donors with a medulloblastoma. Three transmissions were identified at a range of 5 to 7 months, all associated with ventriculoperitoneal shunts. Two medulloblastoma recipients died as the result of metastatic disease, whereas the third is alive with diffuse disease. The rate of donor tumor transmission, in the absence of risk factors, was 7%, whereas in the presence of one or more risk factor this rate dramatically rose to 53% (P<0.01). CONCLUSIONS: Organs from donors with CNS tumors can be used with a low risk of donor tumor transmission in the absence of the following risk factors: high-grade tumors, ventriculoperitoneal or ventriculoatrial shunts, prior craniotomy, and systemic chemotherapy.

Astrocytoma↗
PubMed1988

Pathology, treatment and management of posterior fossa brain tumors in childhood.

Brain tumors are the second most common childhood malignancy. Between 1975 and 1985, 462 newly diagnosed patients were treated at the Children's Hospital of Philadelphia; 207 (45%) tumors arose in the posterior fossa and 255 (55%) appeared supratentorially. A wide variety of histological subtypes were seen, each requiring tumor-specific treatment approaches. These included primitive neuroectodermal tumor (n = 86, 19%), astrocytoma (n = 135, 30%), brainstem glioma (n = 47, 10%), anaplastic astrocytoma (n = 32, 7%), and ependymoma (n = 30, 6%). Because of advances in diagnostic abilities, surgery, radiotherapy, and chemotherapy, between 60% and 70% of these patients are alive today. Diagnostic tools such as computed tomography and magnetic resonance imaging allow for better perioperative management and follow-up, while the operating microscope, CO2 laser, cavitron ultrasonic aspirator and neurosurgical microinstrumentation allow for more extensive and safer surgery. Disease specific treatment protocols, utilizing radiotherapy and adjuvant chemotherapy, have made survival common in tumors such as medulloblastoma. As survival rates increase, cognitive, endocrinologic and psychologic sequelae become increasingly important. The optimal management of children with brain tumors demands a multidisciplinary approach, best facilitated by a neuro-oncology team composed of multiple subspecialists. This article addresses incidence, classification and histology, clinical presentation, diagnosis, pre-, intra- and postoperative management, long-term effects and the team approach in posterior fossa tumors in childhood. Management of specific tumor types is included as well.

Antineoplastic Combined Chemotherapy Protocols↗