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I Vajtai

Publications and source records attributed to I Vajtai.

At least 19 recordsLinked to original sources
PubMed2006

Morbidity in 201 patients with small sized meningioma treated by microsurgery.

BACKGROUND: The management of patients with small, often asymptomatic meningiomas is controversial and includes observation, microsurgery (MS) and stereotactic radiosurgery (SRS). The purpose of this retrospective study was to analyze the morbidity and the extent of removal after MS for small (< or =3 cm) intracranial meningiomas and compare these results to those of SRS reported in the literature. METHODS: All patients with an intracranial meningioma with a maximum diameter up to 3 cm operated on in our institution over a 10 year period (1992-2002) were included in the study and retrospectively analyzed. Patients were grouped into asymptomatic and symptomatic and according to tumor location as: group I (cranial vault, parasagittal, lateral sphenoid), group II (falx, frontobasal, medial sphenoid, parasellar and tentorial), group III (cavernous sinus, petroclival, petrosal, CPA and foramen magnum). FINDINGS: There were a total of 201 patients, of whom 102 were asymptomatic and 99 were symptomatic. The overall risk of permanent neurological morbidity was 4.9% in asymptomatic and 23.2% in symptomatic patients. The combined risk in asymptomatic and symptomatic patients was 5.4% in group I, 11.5% in group II, and 39.9% in group III lesions. Radical removal was achieved in all patients in group I, in 93.7% of group II, and 80% of group III lesions. There was no disease related mortality. CONCLUSIONS: MS provides excellent efficacy and morbidity results in groups I and II meningiomas, especially in asymptomatic patients and might therefore be considered the first choice of treatment for these patients. The results of MS in group III were worse than those of SRS reported in the literature.

Adult↗
PubMed2001

[Fibro-osseous lesion of the central nervous system].

The case of a 53-year-old woman with headache and progressive right sided decline of visual acuity is reported. Computed tomography scans of the brain revealed multiple circumscribed foci of mineralization located over the left frontal and parietal, as well as the right central brain parenchyma. Surgical sampling of the left frontal lesion yielded a conglomerate composed of mineralized vessels, myriad of psammoma bodies, and metaplastic lamellar bone entangled within poorly cellular collagen fibers. No evidence was found of an underlying vascular malformation or tumor, nor was there evidence of parenchymal necrosis of infectious origin. On account of the organoid association of the mesenchymal elements and the mineralized moiety, the lesion was consistent with fibro-osseous lesion of the central nervous system. Also known as "calcifying pseudotumor" of the brain, the origin of this exceedingly rare condition is, as yet, unknown. By analogy, its pathogenesis is likely to involve mechanisms underlying tumoral calcinosis of soft tissues.

Bone and Bones↗
PubMed2001

[Cholesterol granuloma at the sella region: a new method of the differential diagnosis of craniopharyngioma].

Cholesterol-granuloma is a pseudotumoral mass that is believed to enlarge by a self-perpetuating sequence of repeated hemorrhages and reparative tissue reaction. Albeit an almost ubiquitous phenomenon throughout the body, cholesterol-granuloma has recently been appreciated as a distinctive lesion mimicking or associated with craniopharyngiomas. Upon review of a surgical series of 15 purported craniopharyngiomas, the authors identified 3 such occurrences. All were characterized by a predominance of slit-like cholesterol clefts with multi-nucleated giant cells embedded in a fibrotic stroma permeated with lipid laden macrophages, lymphocytes, as well as organizing hemorrhage. Non-craniopharyngioma specific cuboidal epithelium was present in one case. The mean age of patients--all males--with cholesterol-granuloma was 26 years, and all but one had an intrasellar tumor component. Clinical symptoms referrable to hypopituitarism predominated. At variance with the above, patients with adamantinomatous or papillary craniopharyngiomas were 23.5 and 46 years old, respectively, and presented with neurological deficits or ones due to hypothalamic involvement by their tumors. With marginal central nervous tissue present in 53 percent of the specimens, 75 percent of adamantinomatous craniopharyngiomas, but only 12 percent of cholesterol-granulomas showed invasive growth. At present cholesterol-granulomas are conceived as a clinicopathologically distinctive lesion of uncertain origin. They most probably represent a clinically relevant entity in the ontogenesis of adamantinomatous craniopharyngiomas with predisposing factors yet to be elucidated.

Adolescent↗
PubMed2001

[Meningeal melanocytoma].

The authors report on a case of melanocytoma surgically removed from the craniocervical meninges of a 59-year-old man. Although the excision had been incomplete, the patient showed a disease-free course extending well over ten years. On histology, the tumor consisted of moderately cellular arrays of spindle-shaped melanocytes with a vaguely angiocentric whorling tendency, and without evidence of infiltrative growth. Electron microscopy identified tumor cells as ones bearing dendritic processes with complex melanosomes. The latter showed histochemical properties of melanosomal melanin, as well as immunoreactivity for the melanosome-associated markers HMB-45, and MELAN-A. Hallmarks of meningial differentiation were, at the same time, absent. The MIB-1 proliferation rate of the lesion, as assessed in a simultaneous testing of a panel including primary and metastatic central nervous system melanomas, as well as a uveal melanoma remained inferior to 1.5 percent. The data presented and a critical review of the literature suggest that meningeal melanocytoma is a mostly benign nevus-like lesion of neural crest cells with a very limited, although not discountable, margin for aggressive growth.

Aged↗
PubMed2001

Desmoplastic neuroepithelial tumor of infancy in the nevus sebaceus syndrome: report of a unique constellation and review of the literature.

The nevus sebaceus syndrome (NSS) is a neurocutaneous disorder characterized by unilateral hyperplasia of skin appendages and skeletal hemihypertrophy, hemimegalencephaly, or hemiatrophy along with disabling seizures. Despite the proneness of the dermal stigmata to eventually undergo neoplastic transformation, the malformative lesions of the central nervous system rarely evolve into frank tumors. We present the case of a 10-year-old girl with left-sided sebaceus nevi, ipsilateral enlargement of the skull, and a desmoplastic neuroepithelial tumor (DNET) in the right fronto-parietal area of the brain. The tumor was removed by surgery. Histologically, it corresponded to a mitotically active small-cell anaplastic astrocytoma with genuine desmoplasia. Investigative methods included immunohistochemical positivity for glial fibrillary acidic protein, lack of expression of neuronal markers, and ultrastructural documentation of sheaths of basal lamina and collagen around tumor cells. A survey of the literature of brain tumors associated with NSS revealed two cases of histologically verified pilocytic astrocytomas, and one each of a choroid plexus papilloma, a mixed glioma, and a meningioma, as well as a subependymal giant cell astrocytoma--the latter possibly in an overlap syndrome of NSS and tuberous sclerosis. We hypothesize that the tumor described herein, one involving both atypical differentiation and enhanced growth potential, is paradigmatic of neuropathological events to be expected in the NSS.

Astrocytoma↗
PubMed2000

[Lipomatous meningioma: report of two cases and review of the literature].

Lipomatous meningioma is a benign tumor characterized either by an admixture of mature adipocytes and meningioma or the production of triglycerides by neoplastic meningothelial cells assuming a lipoblast-like appearance. The authors report on two instances of this exceedingly rare lesion occurring in the left middle cranial fossa and over the right frontal convexity of two female patients aged 79 years and 60 years, respectively. In the former, the tumor was an incidental autopsy finding, while the latter underwent surgery for symptoms of intracranial space occupation. Light microscopy showed interwoven islands of fatty tissue and transitional meningioma in the first case; whereas a monomorphous signet-ring cell phenotype prevailed in the second. Oil-Red-O staining confirmed the presence of neutral fat in both specimens. Immunohistochemical coexpression of epithelial membrane antigen, vimentin, and S100 protein supported the meningothelial origin of tumor cells. On the other hand, the CD 68 macrophage antigen was not detected. Cytoplasmic lipid droplets along with hallmarks of meningothelial differentiation were visualized ultrastructurally in part of the meningioma component of the first case and throughout the second. These findings are consistent with a metaplastic origin of the adipocytic element. Whatever its histogenesis, lipomatous meningioma may, on occasion, represent a major challenge with therapeutic implications for both preoperative imaging and histological diagnosis.

Aged↗
PubMed2000

[Rhabdoid meningioma: a potentially aggressive new variant].

Rhabdoid meningioma is a recently recognized clinicopathologic entity characterized histologically by cytoplasmic aggregates of intermediate filaments, and clinically by the propensity of such tumors to pursue an aggressive course. The authors report on clinical, radiologic and pathologic findings in three cases of rhabdoid meningioma identified in a retrospective surgical series of 204 meningothelial tumors. Patients included two females, aged 39 and 55 years, and a 54-year-old male. In the first two cases the tumors were located on the right and left lesser sphenoid wing, respectively; in the third case, the right cerebellopontine angle was affected. All three neoplasms evolved on a background on transitional meningioma and were conspicuous for dis-cohesive tumor cells and suppression of syncytical architecture. Immunohistochemistry and ultrastructural examination confirmed the meningothelial origin of inclusion-bearing rhabdoid cells. Although none of the tumors showed evidence of histologic anaplasia and Ki-67 labeling indices remained inferior to 2%, infiltrative growth into adjacent brain was noted in all three cases. On follow-up ranging from 8 months to 6 years, the patients remained either disease-free or alive with nonprogressive residual tumor. On account of their clinical behavior, well-differentiated rhabdoid meningiomas will be accommodated in the category of atypical meningiomas (WHO grade II). Their pathogenesis is likely to involve disrupted cytoskeletal integration of cell motility and proliferation, of which the rhabdoid phenotype may possibly represent a morphologic correlate.

Adult↗
PubMed1999

[Neuromuscular choristoma].

Neuromuscular choristomas are malformative pseudotumoral masses composed of striated muscle and peripheral nerves. This rare condition almost exclusively affects large nerve trunks of infants and young children, and may cause neurologic deficits of variable severity. We report a case of neuromuscular choristoma identified in the lumbosacral lipoma of a 4-month-old boy. The lesion was characterized by an organoid association of myogenic and neurogenic elements reminiscent of neuromuscular units. Myosin immunophenotyping revealed disordered groups of type-I and type-II extrafusal myofibers. There was no immunoreactivity for smooth muscle specific alpha actin. Most participating axons were of the large myelinated type. Pathogenetic theories of neuromuscular choristoma involve aberrant migration of developing peripheral nerves, dysgenesis of muscle spindles, as well as mesenchymal differentiation of the primitive neuroectoderm. Neuromuscular choristomas arising in connection with congenital lipomas may derive from a dysembryogenic process of stem cells of the caudal neural tube.

Choristoma↗
PubMed1999

Chordoid glioma of the third ventricle: confirmatory report of a new entity.

The term "chordoid glioma" was recently introduced to denote a circumscribed, apparently low-grade neoplasm arising in or preferentially involving the third ventricle of middle-aged women. We report biopsy and postmortem findings in a 60-year-old woman with symptoms of forgetfulness, headache, and lethargy. Neuroimaging showed a contrast-enhancing third ventricular mass with obstructive hydrocephalus. The tumor was subtotally resected. Microscopically, it consisted of clusters and strands of epithelioid cells in a mucoid matrix. Its margins were remarkably discrete and showed little tendency to infiltrate surrounding brain parenchyma. The majority of neoplastic cells were glial fibrillary acidic protein (GFAP) and vimentin positive, whereas S100 protein labeled only individual cells. Stains for epithelial membrane antigen (EMA) and cytokeratin were nonreactive. There was no evidence of neuroendocrine differentiation or expression of estrogen and progesteron receptors. Lymphoplasmacellular infiltrates were noted throughout the lesion and at the tumor-brain interface. The MIB-1 labeling index averaged 1.5%. At present, chordoid glioma is considered a glial neoplasm of uncertain histogenesis with distinct clinicopathologic features.

Biomarkers, Tumor↗
PubMed1999

Signet-ring cell ependymoma: case report with implications for pathogenesis and differential diagnosis.

We describe light microscopic, immunohistochemical and ultrastructural features of a signet-ring cell ependymoma (WHO grade II) identified in a surgically resected left cerebellar cystic tumor from a 64-year-old man. Part of the tumor showed clear-cell differentiation. Immunohistochemical coexpression of glial fibrillary acidic protein and epithelial membrane antigen, characteristic of ependymoma, was detected in both components. Sinuous intermediate junctions, cytoplasmic lumina, and scant astroglial filaments were demonstrated by electron microscopy. Signet-ring cell change was shown to be induced by disproportionate cavitation of either microvillus-bearing cytoplasmic lumina or microrosettes. The staining qualities of clear cells were mainly due to paucity and degeneration of subcellular organelles. Therefore, signet-ring cell ependymomas represent a unique anomaly of intra- and extracellular compartmentalization to be distinguished from various unrelated forms of cytoplasmic volume increase, resulting in an optically similar "empty" appearance of tumor cells. As a clinically relevant consequence, signet-ring cell ependymoma must be included in the differential diagnosis of primary or metastatic neoplasms of the central nervous system, having in common a phenotype characterized by overdeveloped optically lucent cell bodies.

Biomarkers, Tumor↗
PubMed1998

[Molecular genetics of gliomas].

Gliomas represent the majority of primary central nervous system tumors in adults. The moderate overall impact of conventional therapeutic regimens on these inherently aggressive neoplasms raises the need for a direct intervention in the biology of neoplastic change. In the last decade important achievements in the molecular genetic basis of deregulated cell-cycle have been brought about, the neuro-oncologic implications of which are reviewed here. Loss of equilibrium between promoting factors and negative control of mitosis emergeus as a general principle, with gene amplification-overexpression operating in the former group, while deletions, loss of function-type mutations and post-transcriptional events prevail at the opposite pole. Damage to regulatory mechanisms will result, as a major consequence, in transgression of one or more of the so-called restriction points of the cell-cycle. Lesions of the genome are further ramified by supracellular processes involving autocrine and paracrine growth-stimulating loops. Malignant progression of gliomas, therefore, can be envisaged as a cumulative sequence of genetic alterations and interactions of tumor cells with their microenvironment.

Adult↗
PubMed1998

[Prognostic markers in the histopathological diagnosis of tumors of the choroid plexus].

Markers of cell proliferation (MIB-1), differentiation (S-100 protein, cytokeratin, transthyretin, GFAP, EMA, CEA), and cell adhesion (CD44) were analyzed immunohistochemically in a biopsy series of 21 chorioid plexus tumors determine their correlation with histological grade and impact on clinical course. The material included 8 papillomas (WHO grade I) and 8 carcinomas (WHO grade III); another 5 tumors were tentatively classified as atypical papilloma. The MIB-1 labeling index of papillomas was 3.7%, while that of carcinomas was 14%. Atypical papillomas (mean: 6%) failed to segregate as a statistically different group. The age and sex of patients, and tumor localization were found not to influence MIB-1 reactivity. High MIB-1 labeling indexes were associated with less favourable postoperative outcome. S-100 protein immunoreactivity was generally reduced in carcinomas, while most tumors were positive for transthyretin and cytokeratin irrespective of their MIB-1 status. Positivity for GFAP and EMA was detected in some tumors of both low- and high grade. CEA was universally negative. The standard isoform of CD44 was only expressed in atypical papillomas and 4 carcinomas showing focal infiltration of adjacent tissues. Western-blot analysis was also carried out in 5 cases to detect CD44. Quantitation of MIB-1 immunohistochemistry may, thus, prove a more readily accessible ancillary method for assessing chorioid plexus neoplasms than analysis of differentiation markers. Our data also suggest that expression of CD44H is instrumental in conferring invasive potential to these tumors and possibly contributes to tumor progression as well.

Adolescent↗
PubMed1998

[Teratoid/rhabdoid tumor of the central nervous system].

Teratoid/rhabdoid tumor is a recently introduced infantile brain neoplasm of uncertain origin clinically characterized by a most aggressive course. We describe the case of a 2-year-old boy and a 7-year-old girl, the former presenting with central fever and hemiparesis, while vomiting and headache were symptoms in the latter. A brain tumor in the right fronto-parieto-occipital and the left fronto-medial parenchyma, respectively, were found and removed by surgery. On histology, both lesions consisted of sheets of ovoid cells with prominent cytoplasm, vesicular nuclei and macronucleoli. In the second case, a spindle-cell component and bone metaplasia were also noted. Ultrastructurally, tumor cells contained whorls of intermediate filaments. Immunohistochemistry revealed a polyphenotypic expression profile including positivity for epithelial membrane antigen, vimentin and a-actin. There was no evidence of a germ-cell origin. Chromosomal translocation involving 22q11 was established cytogenetically in the first case. The teratoid/rhabdoid tumor shares many common traits with renal rhabdoid tumors and primitive neuroectodermal tumors as well as germ cell neoplasms; therefore its being an entity is debated.

Brain Neoplasms↗