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J J Kepes

Publications and source records attributed to J J Kepes.

At least 19 recordsLinked to original sources
PubMed1999

Choroid plexus epithelium (normal and neoplastic) expresses synaptophysin. A potentially useful aid in differentiating carcinoma of the choroid plexus from metastatic papillary carcinomas.

As an incidental finding in paraffin sections of brain tissue used as positive controls for synaptophysin immunostain, the cytoplasm of choroid plexus epithelium present was found to stain strongly positively for this substance. This was subsequently found to be the case in normal choroid plexuses in autopsy material from infancy to old age, as well as in epithelial cells of papillomas and carcinomas of the choroid plexus. The latter findings may prove useful in differentiating choroid plexus carcinomas from metastatic papillary carcinomas of extracerebral origin with the exception of neuroendocrine carcinomas of various sites that are usually positive for synaptophysin.

Adolescent↗
PubMed1999

Neurocytoma of the cauda equina. Case report.

A case of a neurocytoma involving a nerve root of the cauda equina in a 46-year-old woman is reported. The patient presented with a 2-month history of progressive left lower-extremity weakness and pain and decreased ability to walk, as well as complaints of incomplete voiding. A magnetic resonance image revealed a 7-mm oval mass that was located intrathecally and extended from T-12 to L-1 and was adjacent to a nerve root. No lesions were identified at higher vertebral levels. The mass was excised. On histological examination it was found to have classical features of a neurocytoma. To the best of the authors' knowledge, this is the first report of a neurocytoma occurring in that region. A detailed histological description of this case and review of the pertinent literature are provided.

Cauda Equina↗
PubMed1998

Rhabdoid transformation of tumor cells in meningiomas: a histologic indication of increased proliferative activity: report of four cases.

Four cases of meningeal tumors in adults (ages ranging from 28 to 84 years) are presented. All had the typical gross appearance of meningiomas at operation. In three tumors, areas of meningothelial or fibroblastic meningiomas showed transition to cell groups of the rhabdoid type. In the fourth case only rhabdoid cells were encountered, possibly representing a total "take-over" of a meningioma by rhabdoid elements. In the three cases with mixed pattern, the rhabdoid cells showed more anaplasia and atypism than the conventional meningiomatous elements. In case 3 this was expressed by very high MIB-1 positivity in the rhabdoid cells and absence of same in the fibroblastic meningiomatous elements. These cases (the first three with certainty, the fourth with a strong likelihood) indicate that the phenotypic changes to cells with "rhabdoid" morphology may involve meningiomas and that such change is associated with aggressive biologic and clinical behavior of the tumors showing this type of alteration.

Adult↗
PubMed1998

Lipomatous differentiation in ependymomas: a report of three cases and comparison with similar changes reported in other central nervous system neoplasms of neuroectodermal origin.

Three cases of surgically removed ependymomas with lipomatous transformation of tumor cells are reported. Patients' ages were 13, 16, and 48 years at the time of operation. One patient's tumor was located in the third ventricle; the other two occupied paraventricular hemispheric white matter. Histologically all three cases fulfilled the criteria of ependymomas. In case 1, electron microscopy also confirmed this diagnosis, and preoperative radiologic studies (scans) suggested large amounts of lipids to be present in the tumor. Histologically, in all three cases many tumor cells contained fat droplets coalescing into a single large droplet, resulting in an appearance indistinguishable from adipocytes by conventional stains, but maintaining immunohistological positivity for glial fibrillary acidic protein and neuron-specific enolase in the cytoplasmic rims of the affected cells, attesting to their glial nature as opposed to being true adipocytes in a mixed glial/mesenchymal hamartoma. The alterations were also different from the "xanthomatous" changes seen in some gliomas. Lipomatous transformation of neuroectodermal tumor cells has been previously observed in neurocytomas, medulloblastomas, cerebellar and spinal cord astrocytomas, and primitive neuroectodermal tumors. Our three cases represent the first reported ependymomas with such changes. In medulloblastomas of adults, lipomatous changes have been found to signal relatively benign biologic behavior. So far, all three of our patients are doing well, but only more extended follow-up will show whether such benign behavior applies to lipomatous ependymomas as well.

Adolescent↗
PubMed1996

Gliomatosis cerebri. Results with radiation therapy.

BACKGROUND: This review was undertaken to determine the outcome for patients diagnosed in the modern era and treated with radiation therapy. METHODS: Using the tumor registries of six institutions in a large metropolitan area, cases of gliomatosis were identified and retrospectively reviewed. RESULTS: The clinical course for each patient was unique. Deterioration during treatment, brief stabilization, and reversal of the clinical signs and symptoms with stability and high quality of life at 16 months from diagnosis characterized Patients 1, 2, and 3, respectively. CONCLUSIONS: Radiotherapy for gliomatosis appears to stabilize or improve neurologic function in some patients. Its impact on survival will await additional reports and longer follow-up.

Adult↗
PubMed1996

Gliosarcoma developing from an irradiated ependymoma.

A 17-year-old girl was operated for a cystic mass located deep within the left parieto-occipital white matter. Histologically the tumor was an ependymoma with a vascular stroma. In spite of irradiation the tumor recurred locally twice, 1 and 2 years respectively after the original operation. The ependymoma portion of the tumor remained unchanged, but the stroma showed increased vascular hyperplasia at the time of the second operation and transformation into a fibrosarcoma in the third operative specimen. Proliferating cell markers (MIB-1) were positive only in the ependymoma cell nuclei in the first two specimens, but were also extensively present in the nuclei of the fibrosarcoma in the third specimen. In the latter, the fibrosarcoma portion greatly overwhelmed the residual ependymoma islands, but remained sharply delineated from them. This is the first observed case of a gliosarcoma originating from an ependymoma. The histological pattern of this mixed tumor clearly indicates that the source of the sarcomatous portions was the neoplastically transformed fibrovascular stroma of the original tumor, rather than "desmoplastic" alterations of the neoplastic ependymal cells themselves.

Adolescent↗
PubMed1996

Primary glioblastoma multiforme of the oculomotor nerve. Case report.

Tumors of the oculomotor nerve are rare and most instances reported have been schwannomas. The authors present clinical, neuroradiological, and neuropathological findings in a 70-year-old woman with a glioblastoma multiforme (GBM) growing primarily in the proximal part of the left oculomotor nerve. The patient presented with a 1-month history of transient diplopia. Neurological examination revealed an incomplete left-sided oculomotor nerve palsy with no further signs of neurological dysfunction. Cranial computerized tomography and magnetic resonance imaging showed a tumor of the left oculomotor nerve without any obvious signs of penetration into the midbrain or upper pons. Following subtotal removal of the tumor, neuropathological examination of the operative specimen revealed a GBM that had grown diffusely within peripheral nerve tissue. Six weeks after surgery, the patient suddenly died of pulmonary thromboembolism. Postmortem examination of the brain confirmed a large leptomeningeal GBM at the left pontomesencephalic junction with complete destruction of the left oculomotor nerve. To the authors' knowledge, this represents the first case of a GBM of the oculomotor nerve, probably originating from glial cells within the most proximal part of the nerve or the adjacent leptomeninges.

Aged↗
PubMed1995

Synovial cysts of the lumbar spine: diagnosis, surgical management, and pathogenesis. Report of eight cases.

BACKGROUND: Synovial cysts are uncommon extradural degenerative lesions associated with symptoms of lower back pain and radiculopathy. Most of these lesions occur in the lumbar spine at the L4-5 level and to a lesser extent at the L5-S1 and L3-4 levels. METHODS: A retrospective study involving eight patients seen by the neurosurgery service from January 1, 1989, to May 30, 1994, was analyzed. The type, duration, and distribution of symptoms were evaluated, along with the patient's age and sex. All patients had lumbosacral spine x rays and magnetic resonance imaging. Four had a computed tomography-myelogram of the lumbar spine. All patients underwent a laminectomy or hemilaminectomy and cyst excision, and all were followed for a minimum of 1 year. The presence of a synovial cyst was confirmed by histopathology. RESULTS: Of the eight patients, seven had dramatic pain relief with five having complete resolution of pain. The single care of persistent pain was found to be due to scar tissue at the operative site. All five cases of preoperative lower extremity weakness showed complete resolution. Dysesthesia was either unchanged or decreased. CONCLUSIONS: Surgery is a safe, effective treatment for patients with lumbar synovial cysts and is the treatment of choice for these lesions.

Adult↗
PubMed1995

Visualization of injected embolic material (polyvinyl alcohol) in paraffin sections with Verhoeff-Van Gieson elastica stain.

Therapeutic embolization of blood vessels is widely used to treat vascular malformations and to preoperatively decrease the size of bulky tumors by creating iatrogenic infarction. Surgical pathologists are often called upon to identify the presence of embolized material in microscopic slides. Polyvinyl alcohol particles are often used as the material for embolization. On hematoxylin-eosin and other routine stains this substance is almost invisible. These particles stain black and can be sharply outlined by using the Verhoeff-Van Gieson stain.

Embolization, Therapeutic↗
PubMed1994

Adipose tissue and smooth muscle in a primitive neuroectodermal tumor of cerebrum.

We describe a case of an occipital lobe primitive neuroectodermal tumor (PNET) in a 60-year-old man with immunocytochemical evidence of neuronal, glial, smooth muscle and adipose tissue differentiation in the primary tumor and its metastases. This is the first case of PNET of cerebrum in which adipose tissue and smooth muscle has been demonstrated. The possible cells of origin for these mesenchymal elements is discussed.

Adipose Tissue↗
PubMed1994

Case reports: heterotopic brain tissue of middle ear associated with cholesteatoma.

Heterotopic brain tissue reportedly occurs occasionally in various sites, including rare occurrences in the middle ear. Association with cholesteatoma in middle ear cases, however, has not been reported yet. In this article, the authors describe three cases of heterotopic brain tissue in the middle ear associated with cholesteatoma: a 3-year-old boy with recurrent meningitis resulting in right acute otitis media and bony dehiscence of the right attic; a 36-year-old man with chronic right ear infections, right radical mastoidectomy 2 years previously, and brain herniation through the tegmen tympani; and a 65-year-old man with chronic otitis for many years, right ear surgery 25 years previously, and extensive involvement of right middle ear ossicles and mastoid antrum by cholesteatoma. The heterotopic brain tissue in each of these cases was diagnosed by histologic examination, and its glial component was confirmed by immunohistochemical staining for glial fibrillary acidic protein. After a microscopic review of 40 additional surgical pathology cases of cholesteatoma, no evidence of heterotopic brain tissue was found. With these findings, it is suggested that the unusual occurrence of heterotopic brain tissue in the middle ear associated with cholesteatoma may result from local destruction of bone secondary to the cholesteatoma, otitis media, meningitis, or previous surgery.

Adult↗
PubMed1994

Lipidized meningothelial tumor cells in "xanthomatous" meningioma express macrophage antigen.

A case of "xanthomatous" meningioma was examined by light and electron microscopy as well as immunohistology. Lipid-laden "xanthomatous" cells were shown to be meningothelial by all ultrastructural criteria. All tumor cells (lipidized and non-lipidized) expressed vimentin in their cytoplasm, but only the lipidized cells showed the presence of the macrophage marker HAM-56. This finding suggests that, as in some other areas of general pathology, immunological markers may serve as indicators of a specific activity (in this case phagocytosis), rather than merely histogenesis.

Adult↗
PubMed1994

Aneurysm of the left middle cerebral artery caused by myxoid degeneration of the vessel wall.

BACKGROUND: Myxoid degeneration of arterial walls may result in dissection and dissecting aneurysms in extracranial and intracranial portions of cerebral arteries. Rarely, saccular aneurysms may also develop on that basis, but thus far these have only been reported in the cervical portions of the carotid arteries. We describe a case of a nondissecting aneurysm of the left middle cerebral artery caused by myxoid degeneration of the media. CASE DESCRIPTION: A 39-year-old man had acute onset of frontal headache and neck stiffness. Computed tomographic scan and lumbar puncture established the presence of subarachnoid hemorrhage. Angiography demonstrated a left middle cerebral artery aneurysm. This was clipped and the wall biopsied. Microscopically the entire thickness of the vascular wall showed marked myxoid alterations. No dissection was present. The patient had an uneventful recovery. CONCLUSIONS: This observation confirms that myxoid degeneration of arterial walls may cause aneurysms with eventual rupture even in the absence of dissection. Rare cases of this type of aneurysm have been reported to occur in the cervical portions of the carotid arteries, but this is the first reported observation of such changes involving an intracerebral artery.

Adult↗