1/247. Cytologic features of central neurocytomas of the brain. A report of three cases. BACKGROUND: Although cytologic smears are major tools for intraoperative diagnosis of intracranial tumors, cytologic features of central neurocytoma, a tumor that has been recognized for only about 15 years, have not been described. CASES: Typical central neurocytomas were encountered in three patients: 40 years old/M, 44/M and 31/F. Intraoperative cytologic smears were reviewed, and all tumors were subsequently examined by conventional histology, immunohistology and, in one case, electron microscopy. The important cytologic appearances were sheets of round cells with finely stippled nuclear chromatin and perinuclear haloes. Calcospherites, neuropil islands and rosettelike structures were focally encountered. The background neuropil was finely fibrillated, but the tumor cells possessed no appreciable cellular processes. CONCLUSION: Central neurocytomas possess distinct cytologic features that help with the intraoperative distinction from oligodendrogliomas and other intraventricular tumors. A combined radiologic and morphologic approach to the diagnosis of this tumor is advised. ( info) |
2/247. Diffuse leptomeningeal gliomatosis with oligodendroglioma. Leptomeningeal gliomatosis is a primary glioma residing mainly in the leptomeninges. We describe a rare case of diffuse leptomeningeal glioma, occurring in a six year old girl, in which the morphological features of the cellular infiltrates were those of an oligodendroglioma. To our knowledge, this is the fifth case of diffuse oligodendrogliomatosis reported in the English language literature. ( info) |
3/247. The hPMS2 exon 5 mutation and malignant glioma. Case report. patients with Turcot syndrome (TS) are predisposed to colon tumors and primary brain tumors, typically glioblastomas or medulloblastomas. The authors describe a patient with TS featuring a known germline mutation of exon 5 of the hPMS2 mismatch repair gene who developed two metachronous glioblastomas, both with distinct oligodendroglial features. Molecular genetic analysis revealed allelic loss of chromosome 19q in the patient's second tumor but no allelic loss of chromosome 1p. Prominent microsatellite instability was also found in this tumor, consistent with a germline mismatch repair defect. Because this patient had an unusual underlying condition and his tumor had a unique histological appearance for TS, it was hypothesized that this genetic defect may predispose to malignant gliomas with oligodendroglial features. The authors therefore evaluated whether sporadic glioblastomas and oligodendrogliomas undergo mutations of this region of the hPMS2 gene. However, single-strand conformation polymorphism analysis of hPMS2 exon 5 failed to reveal mutations in 20 sporadic glioblastomas and 16 sporadic oligodendroglial gliomas. Thus, although it is possible that the germline hPMS2 exon 5 mutation may predispose to glioblastomas with an oligodendroglial component, the same genetic defect is not commonly involved in sporadic oligodendrogliomas or glioblastomas. ( info) |
4/247. Familial gliomas : a case report. Two non-twin brothers were found to have intracranial malignant neoplasms. The age of presentation was third and fourth decade but the onset was simultaneous, at the same time. diagnosis in each of them was made by computed tomography and confirmed by histopathology. Elder among them had cellular ependymoma and the younger had oligodendroglioma. Both the brothers received radiotherapy post operatively and were surviving asymptomatically without any neurological deficit, leading active life as police constable, 12 months after surgical treatment. ( info) |
5/247. Intraoperative validation of functional magnetic resonance imaging and cortical reorganization patterns in patients with brain tumors involving the primary motor cortex. OBJECT: The purpose of the present study was to compare the results of functional magnetic resonance (fMR) imaging with those of intraoperative cortical stimulation in patients who harbored tumors close to or involving the primary motor area and to assess the usefulness of fMR imaging in the objective evaluation of motor function as part of the surgical strategy in the treatment of these patients. methods: A total of 11 consecutive patients, whose tumors were close to or involving the central region, underwent presurgical blood oxygen level-dependent fMR imaging while performing a motor paradigm that required them to clench and spread their hands contra- and ipsilateral to the tumor. Statistical cross-correlation functional maps covering the primary and secondary motor cortical areas were generated and overlaid onto high-resolution anatomical MR images. Intraoperative electrical cortical stimulation was performed to validate the presurgical fMR imaging findings. In nine (82%) of 11 patients, the anatomical fMR imaging localization of motor areas could be verified by intraoperative electrical cortical stimulation. In seven patients two or more activation sites were demonstrated on fMR imaging, which were considered a consequence of reorganization phenomena of the motor cortex: contralateral primary motor area (nine patients), contralateral premotor area (four patients), ipsilateral primary motor area (two patients), and ipsilateral premotor area (four patients). CONCLUSIONS: Functional MR imaging can be used to perform objective evaluation of motor function and surgical planning in patients who harbor lesions near or involving the primary motor cortex. Correlation between fMR imaging findings and the results of direct electrical brain stimulation is high, although not 100%. Based on their study, the authors believe that cortical reorganization patterns of motor areas might explain the differences in motor function and the diversity of postoperative motor function among patients with central tumors. ( info) |
6/247. Neuropsychological assessment of an 8-year-old child following excision of a right temporal lobe oligodendroglioma. A case of right temporal lobe oligodendroglioma in an 8-year-old female is reported. This case is unusual, because of the rarity of this type of tumour in children, because it was accompanied by seizure activity which is atypical, and because it highlights the difficulties in diagnosis. Prior to diagnosis, the background had included normal early development, followed by gradual development of partial complex seizures with poor response to medication in the absence of clear findings on EEG or CT. Considered to have been present prior to 1 year of age, the tumour was purported to be the aetiological base for seizure activity, which ceased after surgical excision. Post-surgical difficulties with academic progress and behaviour resulted in referral for neuropsychological evaluation, which revealed lowered overall cognitive functioning with deficits in processing speed, abstract verbal reasoning, concept formation, visual perception, visual reasoning, scanning, attention, memory, academic attainment and learning, and clerical motor speed. Behavioural functioning revealed impairment in social skills, irritability, impulsivity, and mood changes. The relative contributions of medication (adverse reaction and toxicity), long term seizure activity, early age of onset, and presence/excision of tumour are difficult to ascertain specifically. Findings appear consistent with those of right temporal lobe brain injury. ( info) |
| PURPOSE: To report a case of oligodendroglioma originating from the accessory glia of retina. METHOD: Case report of a 72-year-old woman with a tumor in the temporal fundus of the right eye that was suspected to be choroidal melanoma. Enucleation was declined, but 5 years later, because of tumor growth, pain, and loss of light perception, the globe was enucleated. RESULTS: Histopathologic examination disclosed a neuroepithelial tumor with a structure of oligodendroglioma. melanoma and metastatic tumor were excluded. CONCLUSIONS: Oligodendrogliomas are rare in the retina but may originate from retinal oligodendrocytes. This case suggests that the differential diagnosis of choroidal melanoma should include the possibility of oligodendroglioma. ( info) |
8/247. Oligodendroglial gliomatosis cerebri: (1)H-MRS suggests elevated glycine/inositol levels. Oligodendroglial gliomatosis cerebri is very rare. We describe 42-year-old woman who had low-grade oligodendroglial gliomatosis cerebri confirmed on stereotactic biopsy. The diffuse nature of the tumour was apparent clinically, neurophysiologically, on MRI and on proton magnetic resonance spectroscopy (MRS). She also had an isolated, false-localising partial seventh nerve palsy. MRS, of which there are no previous reports, suggested elevated glycine/inositol levels. This might be explained by the cell lineage from which the tumour arose. ( info) |
9/247. Spinal oligodendroglioma with gliomatosis in a child. Case report. The authors present a rare case of oligodendrogliomatosis in a child, which they believe originated from a primary spinal cord tumor. At 2.5 years of age this boy developed poor balance, neck stiffness, and a regression in developmental milestones. A computerized tomography (CT) scan of the head initially revealed ventriculomegaly and multiple cystic cerebellar lesions. In addition, magnetic resonance (MR) imaging revealed a cystic intramedullary lesion involving the cervical spinal cord. A CT scan of the head and an MR image obtained 3 years later demonstrated diffuse small cysts on the surface of the brainstem, cerebellum, medial temporal and inferior frontal cortices, subcortical white matter, and corpus callosum suggestive of leptomeningeal tumor spread. Analysis of pathological specimens obtained at surgery showed neoplastic glial cells with small, uniform nuclei and perinuclear clear zones. The cells appeared to migrate along the subpial space but no tumor cells were present in the subarachnoid space. These findings were compatible with a diagnosis of oligodendrogliomatosis cerebri. Despite having a complicated course, chemotherapy with carboplatin has provided the patient with long-term palliation and a high quality of life. This case may represent the fifth report in the literature of oligodendrogliomatosis occurring in a child but only the third occurring with a spinal primary tumor. ( info) |
| OBJECTIVE AND IMPORTANCE: To demonstrate the usefulness of positron emission tomography-magnetic resonance imaging (MRI) coregistration for differentiation of radiation necrosis and recurrent tumor in stereotactic planning. CLINICAL PRESENTATION: T1-weighted MRI scans of a 43-year-old woman revealed a contrast-enhancing lesion 4 years after open removal of a recurrent, right parieto-occipital Grade II oligodendroglioma and subsequent external radiation therapy. The suspected contrast-enhancing lesion revealed only moderate tracer uptake (1.3 times the uptake in the contralateral normal cortex) in a coregistered [11C]methionine positron emission tomographic scan. Approximately 15 mm posterior and mesial to the center of the contrast-enhancing lesion, however, an area of higher tracer uptake was found (1.8 times that of the contralateral normal cortex), which exhibited only very minor contrast enhancement on MRI. TECHNIQUE: The coregistered images were used for planning stereotactic serial biopsies, from the contrast-enhancing lesion as well as from the area with higher methionine uptake. Histological examination demonstrated that the contrast-enhancing lesion with low methionine uptake was necrotic tissue, and the nonenhancing area with high methionine uptake was recurrent tumor. CONCLUSION: High-resolution positron emission tomography and modern coregistration techniques allow differentiation of contrast enhancement and methionine uptake in irradiated brain tissue within small areas. High methionine uptake is typical for recurrent tumor tissue and can be differentiated from minor tracer accumulation resulting from disruption of the blood-brain barrier or macrophage activity within the necrotic area. ( info) |