1/152. Primary melanocytoma arising from the thoracic leptomeninges case.Primary melanocytoma arising from the leptomeninges of the spinal cord is very rare. A surgical specimen of a thoracic meningeal tumor was resected from a 75-year-old woman complaining of gait disturbance was investigated. magnetic resonance imaging and myelography showed a dumb-bell-type tumor in the subdural space at the 1st to 2nd thoracic vertebrae. The tumor was subtotally resected because of adhesion to the lamina and thoracic medulla. The localized, gelatinous black tumor showed a well-defined margin without dissemination or infiltration. The tumor had a thin capsule and was composed of solid proliferation of neoplastic melanocytes. Neither whorl formation nor foci of palisaded nuclei were observed. The neoplastic cells were of two major types: an epithelioid- or polygonal-shaped type and a spindle-shaped type, and had a large nucleus, a prominent nucleolus, coarse chromatin, and melanin-pigments in their cytoplasm. Only a few mitotic figures were observed. They were positive for HMB-45 and S-100 protein. This case was considered to be primary melanocytoma arising from the thoracic leptomeninges.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
2/152. A new subtype of meningioma.Three patients with small meningiomas presented with diffuse cerebral edema that was out of proportion to the size of tumors. All lesions were small and no brain invasion or unusual tumor vascularity or dural sinus involvement was noted in any of the three cases. Tumor material was subjected to conventional and immunohistochemical stains. All three tumors showed benign meningothelial components, prominent formation of hyaline inclusions (pseudopsammoma bodies), and striking vascular mural proliferation of small dark cells. All patients have remained asymptomatic without any evidence of tumor recurrence after a follow-up of 4-6 years. These tumors showed proliferation of pericytes in blood vessel walls and, therefore, represent a new subtype of meningothelial meningioma. In the study presented here, the location, size, histotype, and clinical findings that may influence the development of peritumoral brain edema are discussed in detail.- - - - - - - - - - ranking = 2keywords = life (Clic here for more details about this article) |
3/152. Rosai-Dorfman disease presenting multiple intracranial lesions with unique findings on magnetic resonance imaging. Case report.Rosai-Dorfman disease (RDD) is a rare idiopathic histoproliferative disease affecting the systemic lymph nodes. Although an extranodal lesion has also been recognized, central nervous system involvement is extremely rare. To the authors' knowledge, only 20 cases of intracranial lesions have been reported previously. Intracranial RDD is clinically and radiologically difficult to distinguish from meningioma, and histological examination is essential for a definitive diagnosis. The authors treated a large frontal lobe tumor associated with multiple meningeal nodules in a 67-year-old patient presenting with diplopia and headache. Radiological examination indicated that the mass was an inflammatory lesion rather than a meningioma. Microscopically the lesion consisted of mixed inflammatory infiltrate with marked emperipolesis, which is characteristic of RDD. A review of the literature and a discussion of the differential diagnosis of this rare lesion are also presented.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
4/152. meningioma with meningioangiomatosis: a condition mimicking invasive meningiomas in children and young adults: report of two cases and review of the literature.Meningioangiomatosis is a malformative meningovascular proliferation that occurs sporadically and in patients with neurofibromatosis type 2. Its histologic features of perivascular proliferation of elongated fibroblast and meningothelial cells trapping islands of gliotic cortex may be erroneously interpreted as invasion when an overlying meningioma is present. We report two cases of meningioangiomatosis associated with meningioma and review the literature on the subject for a total of six cases. The age of patients ranged from 9 months to 33 years. All cases were single lesions, and none had clinical evidence of neurofibromatosis type 2. Meningiomas in children have been regarded as having more aggressive behavior than their adult counterparts, with more frequent invasion of the underlying brain. The lack of correlation between brain invasion and recurrence observed in series of meningiomas in young patients may suggest that some of these lesions are meningioangiomatosis associated with meningioma rather than invasive meningiomas.- - - - - - - - - - ranking = 2keywords = life (Clic here for more details about this article) |
5/152. Leptomeningeal melanomatosis with multiple cutaneous pigmented nevi: tumor cell proliferation and malignant transformation in an autopsy case.We experienced a rare case of leptomeningeal melanomatosis. The proliferative activity and nuclear accumulation of p53 in this tumor were examined, since the relationship between this tumor type and growth has not yet been elucidated. A 33-year-old Japanese man was shown to have leptomeningeal melanomatosis with multiple cutaneous pigmented nevi. The autopsy findings showed the presence not only of benign diffuse melanosis of the leptomeninges but also of leptomeningeal melanomatosis in the subarachnoid space and brain parenchyma. In the brain parenchyma, the direct invasion of tumor cells from the subarachnoid space and Virchow-Robin spaces filled with melanoma cells were observed. Multiple hemorrhagic areas invaded by melanoma cells were also present. Immunohistochemical staining with a monoclonal antibody to melanoma cells showed positivity in the tumor cells. Proliferation analysis using the MIB-1 antibody demonstrated that the labeling index of tumor cells invading brain parenchyma (2.54%) was higher than that in other lesions of the inner (0.89%) and outer layer (0.76%) of the subarachnoid space. Nuclear accumulation of p53 protein was rarely seen in the tumor cells. We reported a case of leptomeningeal melanomatosis. Higher proliferative activity was found in invading cells of the brain parenchyma. Malignant transformation of the tumor did not appear to be associated with p53 gene mutation.- - - - - - - - - - ranking = 7keywords = life (Clic here for more details about this article) |
6/152. Vascular endothelial growth factor and malignant transformation of a meningioma: case report.Although meningiomas are common benign intracranial tumors which grow slowly, we occasionally encountered aggressive or malignant ones. One of these cases showed an interesting relationship to vascular endothelial growth factor (VEGF). A 39-year-old woman underwent resection of a sphenoid ridge meningioma; the residual tumor showed evidence of malignant transformation 14 years later. We immunohistochemically examined six successive surgical specimens plus the autopsy specimen of this patient's tumor for proliferative potential, vascularity, and expression of various growth factors. In the latter stage of clinical courses, proliferative potential and vascularity was seen to increase year by year. Expression of VEGF was upregulated and correlated with vascularity. On the other hand, basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF), and epidermal growth factor (EGF) were not overexpressed in this tumor. This case suggests that overexpression of VEGF and increased angiogenic potential might be involved in malignant transformation of meningiomas.- - - - - - - - - - ranking = 2keywords = life (Clic here for more details about this article) |
7/152. granular cell tumor of intracranial meninges.BACKGROUND: granular cell tumor (GCT) is a benign neoplasm composed of a proliferation of round or polygonal cells that contain eosinophilic granular cytoplasm. The most common locations are tongue and subcutaneous tissue, but a variety of other sites may be involved including the central nervous system (CNS). Most CNS GCT arise in the pituitary, but rare cases involving brain and leptomeninges have been described. Extracranial GCT are usually S-100-positive, but those of the CNS, as well as the congenital variant of GCT, can be S-100-negative. CASE REPORT: We report an incidental autopsy finding of a 2.5 mm GCT that arose in the intracranial meninges overlying the anterior superior cerebellar vermis. RESULTS: The neoplasm had abundant eosinophilic, granular cytoplasm that was PAS-positive and diastase-resistant. Immunohistochemical studies showed that the neoplasm was positive for CD68 and negative for S-100, GFAP, EMA, and keratin. Thus, the immunophenotype is consistent with non-neural origin. CONCLUSION: Although this lesion in this circumstance was of no clinical significance, knowledge of the occurrence of GCT at this site broadens the differential diagnosis of eosinophilic lesions of the leptomeninges.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
8/152. radiosurgery of meningeal melanocytoma.The authors present a case of meningeal melanocytoma arising from Meckel's cave. A coal-black, vascular tumor was partially removed by surgery. Histopathologically, the tumor lacked anaplastic features. Immunohistochemical studies confirmed that the tumor was of neuroectodermal origin and had low proliferating activity. The patient underwent gamma knife radiosurgery for the residual tumor, in which 25 Gy of radiation was delivered to the tumor margin. Three years after irradiation, the tumor showed marked shrinkage without complication.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
9/152. Secondary intracranial meningiomas after high-dose cranial irradiation: report of five cases and review of the literature.PURPOSE: To review cases of secondary intracranial meningiomas following high-dose cranial irradiation (>/= 10 Gy) identified in slovenia between 1968 and 1998, to determine their histological profile and to review the literature on this topic. methods AND MATERIALS: Personal files of patients treated for secondary intracranial meningioma during a 31-year period were reviewed. In cases which met the criteria for radiation-induced tumors, steroid hormone receptor and Ki-67 status were analyzed. For the literature review, computerized database systems and reference lists from respective publications were used. RESULTS: Five patients (2 females, 3 males), 3-11 years old at the time of cranial irradiation, developed secondary meningioma after a latency period of 9.5-31.5 years. Three patients had multiple tumors and 2 developed recurrent disease. Of 9 histologically examined tumors, 5 were graded as benign and 4 as atypical meningiomas, with Ki-67 proliferative index 3.2 /- 3.6 and 10 /- 6, respectively. The ratio between positive and negative meningiomas regarding immunostaining for progesterone and estrogen receptors was eight-to-one and six-to-three, respectively. Cumulative actuarial risk of secondary meningioma in a cohort of 445 children 16 years or younger treated with high-dose cranial irradiation between 1968 and 1990 in slovenia at 10, 20, and 25 years was 0.53%, 1.2%, and 8.18%, respectively. Out of 126 cases of radiation-induced meningiomas reported, 57% were females and 43% were males, with mean age at presentation 33 /- 17.3 years. The majority (68%) of patients was irradiated during childhood. The latency period was significantly shorter in those who aged 5 years or less at the time of cranial irradiation (p = 0.04), and in those with atypical/anaplastic tumor (p = 0.01). Correlation between radiation dose and latency period could not be found. CONCLUSION: Secondary meningiomas following high-dose cranial irradiation are characterized by younger age at presentation, by higher male-to-female ratio and by biologically more aggressive variants compared to primary spontaneous meningiomas. Latency period correlated with the age at the time of cranial irradiation and with tumor grade but not with irradiation dose. Ki-67 immunoreactivity correlated with histological grade. The progesterone and estrogen receptor immunoreactivity was high. The risk for development of secondary meningioma after high-dose cranial irradiation was increasing with the time of follow-up.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
10/152. Acoustic intrameatal meningiomas.BACKGROUND: The sporadic finding of an acoustic intrameatal meningioma stimulated the authors to the present study. An analysis of the cases previously reported in the literature aimed to outline a preliminary account about biological, radiological and surgical specific hallmarks of these tumours. methods: Eight previous cases of meningiomas, meeting the prerequisite of origin and situation within the internal acoustic canal, have been discovered in the known literature since 1975. A further case was recently observed in our experience. The cases in the series showed no sex prevalence and in most of them the age of incidence was comprised between the fifth and sixth decade of life. hearing loss was the prevalent symptom, lasting 1 month to 7 years before presentation. Myelocisternography, myelo-CT or high resolution CT/MR revealed no specific radiological features to distinguish small intrameatal meningiomas from the more frequently occurring vestibular schwannomas, while CT scan with bone algorithm could point out valuable indirect details for differential diagnosis. Various surgical approaches, i.e. middle fossa, translabyrinthine and retromastoid, were utilized by the different authors. RESULTS: Basing on apparent individual surgical preference, one of three different surgical routes (translabyrinthine, middle fossa, retromastoid) was chosen for 10 procedures in 9 patients. In all, except two cases the impression at surgery was of complete tumour removal. CONCLUSIONS: The possibility for meningiomas to recur and invade the surrounding bone requires a differential diagnosis from vestibular schwannomas. In the absence of intrinsic distinctive signs, radiological evaluation of peritumoral bone alterations could help diagnosis. Although the various surgical routes have often proved effective, temporal bone invasion justifies more extensive approach even in small tumours.- - - - - - - - - - ranking = 1keywords = life (Clic here for more details about this article) |
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