Intracytoplasmic lumina in meningioma: an ultrastructural and immunohistological study

Three surgically removed meningotheliomatous meningiomas with hyaline inclusions or pseudopsammoma bodies were studied. Ultrastructurally, the lumina seemed to be predominantly intracytoplasmic, defined by a systemic unit membrane; they displayed abundant microvilli and contained granular or filamentous material, vacuoles, vesicular bodies, and lamellar structure. The cytoplasm surrounding the intracytoplasmic lumina was electron-dense and contained tonofilaments and desmosomal junctions. All three meningiomas showed expression of carcinoembryonic antigen, cytokeratin, and epithelial membrane antigen in the cells surrounding the hyaline bodies. Keratin, alpha-1-antitrypsin, and immunoglobulin M showed weak positive staining. There was widespread vimentin except in the cells with hyaline inclusions. Glial fibrillary acidic protein and S100 were negative. These results provide additional confirmation of immunohistochemical data that can serve as evidence for epithelial and secretory differentiation in meningiomas.     

Rhabdoid papillary meningioma.

We have studied an uncommon case of rhabdoid papillary meningioma in a 15-year-old boy with a dura-based mass arising in the left posterior fossa. The patient exhibited prominent extracranial extension during the past 6 years, consisting of a mixture of both perivascular pseudopapillary growth and rhabdoid cytologic features of neoplastic meningothelial cells. The meningothelial features were evidenced by the focal whorl formation of tumor cells, coexpression of epithelial membrane antigen and vimentin, and ultrastructural findings of interdigitated cytoplasmic process and intercellular junction. However, the regional and histologic resemblances to ependymoma were further complicated by unexpected focal expression of glial fibrillary acidic protein, neurofilament, and alpha-smooth muscle actin of the tumor cells. The rhabdoid morphology was characterized by sheets of tumor cells with eccentric nuclei and abundant eosinophilic cytoplasm with often recognizable intracytoplasmic hyaline inclusions. These inclusions revealed ultrastructural paranuclear whorls of intermediate filaments, ruling out the other forms of intracytoplasmic eosinophilic inclusions resembling rhabdoid morphology. Diagnosis of an unusual rhabdoid papillary meningioma with aggressive behavior is resoluble by immunohistochemical and ultrastructural analyses.     

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.     

Secretory meningioma with elevated serum carcinoembryonic antigen level.

We recently encountered a 68-year-old woman with right sphenoid wing meningioma of the secretory type accompanied by an elevated serum carcinoembryonic antigen level. This case was neuroradiologically characterized by marked brain edema. Histologically, the lesion was rated as having meningothelial components and was rich in blood vessels and pseudopsammoma bodies. Carcinoembryonic antigen, epithelial membrane antigen, keratin, and cytokeratin were immunohistochemically detected in the pseudopsammoma bodies and the cells producing these bodies.     

Meningioma, meningeal hemangiopericytoma (angioblastic meningioma), peripheral hemangiopericytoma, and acoustic schwannoma. A comparative immunohistochemical study

The relationship between meningeal hemangiopericytoma (angioblastic meningioma), meningiomas of meningothelial derivation, and peripheral hemangiopericytoma is controversial; and immunohistochemical studies have yielded conflicting results. Likewise, immunohistochemistry has been touted as a reliable means of differentiating fibrous meningioma from acoustic schwannoma. By the immunoperoxidase method, we studied 40 meningiomas (11 meningotheliomatous, four transitional, 11 fibrous, three secretory, four metaplastic, one xanthomatous, one papillary, four atypical, one malignant), five arachnoid granulations, 13 angioblastic meningiomas, nine peripheral hemangiopericytomas, and seven acoustic schwannomas. Antisera to vimentin, epithelial membrane antigen (EMA), keratin, S-100 protein, carcinoembryonic antigen (CEA), desmin, factor VIII, Ulex europeaus, and glial fibrillary acidic protein (GFAP) were utilized. All meningiomas and arachnoid granulations stained for vimentin and EMA; 15% and 12% of meningiomas were S-100 and keratin positive, respectively. The latter was noted primarily in areas of secretory (pseudopsammomatous) differentiation. In contrast, all angioblastic meningiomas stained for only vimentin. This profile of immunoreactivity was also seen in the peripheral hemangiopericytomas, with the exception of single cases that stained focally for EMA and S-100 protein, respectively. Acoustic schwannomas all stained positively for S-100 protein, vimentin, and were variably reactive for EMA, a pattern not distinct from meningioma. We conclude that (a) meningiomas express both epithelial and mesenchymal markers as do arachnoid granulations, (b) that angioblastic meningiomas demonstrate only mesenchymal markers, (c) that angioblastic meningiomas express identical markers to peripheral hemangiopericytoma and should thus be considered a variant thereof, (d) among meningiomas, CEA and keratin appear to be relatively specific markers for the "secretory" variant, and (e) because of overlap in S-100 and EMA reactivity, these markers are unreliable in differentiating meningioma from acoustic schwannoma.     

Electron microscopic study of hyaline inclusions in meningioma (author's transl)

Three cases of meningioma showing hyaline-like inclusions by light microscopy were studied at the fine structural level. The hyaline-like inclusions were found to be cyst-like contents of variable size filled with moderately dense finely filamentous material arranged either in a reticulated configuration or closely packed and appearing relatively homogeneous and dense. The surrounding cyst membrane is characterized, especially in the smaller inclusions, by the presence of microvilli. The reticulated material is found at the inner aspect of the cyst membrane and is attached to it. It is identical to the coating material seen at the surface of various epithelia. In addition to the filamentous material, minute membrane-bounded vesicles are often found floating within the larger cysts. The inclusions apparently begin as small, microvillous-filled cysts which eventually cluster and presumably fuse to form a single large body.     

Secretory meningioma: immunohistochemical findings and evaluation of mast cell infiltration

Secretory meningiomas constitute a relatively rare subtype of meningiomas, accounting for only 1.1% at our institution, with a 6:1 predominance of female patients. This study aimed to obtain more information about the immunohistochemical characteristics of this histological entity, and to analyse the effects of histological factors such as the presence of mast cells on the radiological evidence of surrounding tumour oedema that frequently occurred in this subtype of meningioma. Fourteen cases of secretory meningioma were examined. Relevant clinical information was obtained from the patient files. Peritumoural oedema was determined either by CT or MRI scans and graded as small, moderate and severe. In order to perform the quantitative evaluation of mast cells in secretory meningiomas in a comparison with other meningiomas, 14 non-secretory meningiomas were randomly selected and used as a control group. The immunohistochemical staining of carcinoembryonic antigen was positive within the secretory droplets and the cells surrounding them in all cases. Ki 67 (MIB 1) proliferative index mean values were 2.4%, indicating low expression in all secretory meningiomas. Moreover, from our statistical analysis, there is no clear-cut pattern of various types of cytokeratins emerging in secretory meningiomas. The secretory meningiomas were characterized by a significantly increased number of mast cells as compared with non-secretory meningiomas of different grades. As the present clinical findings and laboratory results could not confirm a correlation between mast cell density and radiological evidence of oedema, further studies of mediators are warranted.     

A case of chordoid meningioma]

Chordoid meningioma is a very rare variant, especially in adults. We report an adult case of chordoid meningioma. A 52-year-old man was admitted to our hospital due to right hemiparesis. MRI revealed a left temporal convexity mass that showed two structures; the cerebral layer was shown as an isointensity area on T1WI and T2WI, and the dural layer seemed relatively hypointense on T1WI and hyperintense on T2WI. The tumor was well enhanced with gadolinium, especially on the dural side. A left external carotid arteriogram showed tumor stains with feeding vessels from the left middle meningeal artery. The tumor was totally removed via fronto-temporal craniotomy. Histological examination of the surgical specimen revealed two different structural components, meningothelial meningioma on the cerebral side, and chordoid meningioma on the dural side, consisting of clustering spindled cells and partly vacuolated ones in the mucoid stroma. In immunohistochemical examination, tumor cells showed positive staining for vimentin and epithelial membrane antigen (EMA), and negative for cytokeratin. From the above findings, this case was diagnosed as chordoid meningioma in an adult, a very rare variant of meningioma.     

Pseudopsammomatous meningioma with elevated serum carcinoembryonic antigen: a true secretory meningioma. Case report

A sphenoid-wing meningioma in a 60-year-old woman was accompanied by elevated serum carcinoembryonic antigen (CEA) levels, which returned to normal after removal of the tumor. Light microscopic examination revealed a secretory meningioma containing numerous pseudopsammoma bodies and a prominent vascular pattern. Immunohistochemical analysis showed the tumor cells and pseudopsammoma bodies to be CEA-positive. This case illustrates the possibility that secretory meningioma may be associated with clinically detectable secretion of CEA. The report also documents the rare occurrence of elevated serum CEA in a primary benign intracranial tumor.     

Immunopathological significance of Ig G in meningioma in relation to the pseudopsammoma bodies

Summary We described two histochemical patterns of Ig G deposits in meningioma and discussed the pathogenesis of Ig G deposits. In meningioma with pseudopsammoma bodies, Ig G was secreted from tumour cells which differentiated to secretory epithelial cells, and was found to deposit in the pseudopsammoma bodies. However, in meningioma without pseudopsammoma bodies, Ig G was derived from plasma and became deposit around the blood vessels in the meningioma tissue.     

Convexity meningioma associated with Werner's syndrome--histopathological findings with electron microscopical and immunohistochemical findings

Werner's syndrome is rare and autosomal recessive condition with multiple progeroid features. There is an increased incidence of neoplasm such as meningioma or sarcoma in association with this syndrome. However, the pathogenesis of this subject is still controversial. To date, only two cases have been reported, dealing with surgical operation. Our present case of a 39-year-old woman who had a meningioma associated with Werner's syndrome is the third of such cases. In this rare case we did histopathological examinations including electron microscopic and immunohistochemical studies, which showed intense proliferation of the connective tissue in the tumor tissue. The present morphological study may imply a close relationship between proliferation of collagen fibers in the meningioma and the aberration of connective tissue metabolism in context of theory of the pathogenesis of Werner's syndrome.     

Primary pulmonary malignant meningioma.

Fewer than 20 cases of primary pulmonary meningioma have been reported. Most of these cases have been histologically and clinically benign. We report an unusual case of primary pulmonary malignant meningioma with atypical histologic features and malignant behavior. A computed tomography scan of the head did not show evidence of tumor. The right upper lobe mass was resected and showed features of an atypical meningioma with loss of architectural pattern, mild nuclear pleomorphism, increased mitotic counts (up to 15 mitotic figures per 10 high power fields), and focally prominent nucleoli. Focally, cells with rhabdoid features were identified. The tumor's immunohistochemical and ultrastructural profiles were consistent with a meningioma. The tumor stained negative for estrogen and focally positive for progesterone receptors and had a MIB-1 labeling index (marker of cell proliferation) of 9.2%. Approximately 5 months after the initial resection, the patient experienced a tumor recurrence with multiple lymph node metastases, spread to the middle and lower lobes of the right lung, and metastasis to the diaphragm. Rarely, primary pulmonary meningiomas may present as high-grade malignant lesions.     

Microcystic meningioma arising in a mixed germ cell tumor of the testis: a case report.

We report a case of a microcystic variant of meningioma arising in a mixed germ cell tumor of the testis composed predominantly of mature and immature teratoma with elements of seminoma and embryonal carcinoma. We believe this is the first such case of a meningioma arising in a teratoma within a gonadal or extragonadal site. The meningiomatous component showed positive immunohistochemical staining for epithelial membrane antigen and a lack of staining for cytokeratin, factor VIII, CD31, and alpha-fetoprotein. Recognition of a non-germ cell tumor arising in the setting of a teratoma in the testis may be prognostically important depending on the nature of the non-germ cell component and whether it has spread beyond the testis.     

A case of suprasellar hemangioblastoma with thoracic meningioma

Supratentorial hemangioblastoma is encountered very rarely, with only about 110 cases reported. This report concerns a case of a suprasellar hemangioblastoma associated with thoracic meningioma. A 62-year-old man was admitted with visual disturbance of the left eye. T2-weighted magnetic resonance imaging (MRI) showed a high signal intensity mass in the suprasellar region without perifocal edema. T1-weighted MRI with gadolinium showed a homogeneously enhanced mass. The angiogram revealed remarkable tumor staining originating from the right and left internal carotid arteries (ICA) and the left external carotid artery (ECA). On the basis of the pre-operative diagnosis of tuberculum sellae meningioma, total tumor removal was performed. Photomicrographs of the specimen showed numerous capillaries divided by stroma cells. Positive immunostaining for factor VIII related antigen (F VIII RAg) was observed in endothelial cells, but immunostaining for epithelial membrane antigen (EMA) was not observed in any cells. A diagnosis of suprasellar hemangioblastoma was made on the basis of these findings. The patient suffered paraparesis on the postoperative seventh day. Since MRI showed a thoracic tumor, a second total tumor removal was performed. The tumor was diagnosed as a meningothelial meningioma. The patient was discharged without evidence of new neurological deficits. Our experience shows that, when a mass is vascularized in the cerebral hemisphere, the possibility of hemangioblastoma needs to be taken into consideration.     

Sclerosing adenosis of the prostate gland. A lesion showing myoepithelial differentiation.

Sclerosing adenosis of the prostate is a rare lesion characterized by the proliferation of variably sized glands in a cellular stroma. We report light microscopic, immunohistochemical, and ultrastructural studies in 22 examples from 15 patients. Two cases were identified in 100 consecutive prostates embedded by a whole organ method, giving a prevalence of 2%. Antibodies directed against the following antigens were used: high-molecular-weight cytokeratin (CKH; 34 beta E12); cytokeratin (CK; AE1/AE3), prostatic acid phosphatase (PAP), prostate-specific antigen (PSA), S-100 protein, muscle-specific actin (HHF35), and vimentin (Vim). Cells within the glandular component demonstrated positive reactivity for CK, CHH, PSA, and PAP, indicating a prostatic epithelial origin. In addition, a distinct population of cells reacting for muscle-specific actin and S-100 protein was identified within this glandular element. Adequate material for ultrastructural study was available in five cases; all showed the presence of flattened cells located between the basement membrane and secretory epithelial cells, which had features typical for myoepithelial differentiation. Although the prostate gland does not normally contain myoepithelial cells, we have documented their consistent presence in this unusual lesion; we believe these cells arise by a metaplastic process from the prostatic basal cells.     

脑膜瘤血管内皮生长因子表达与瘤周水肿及预后的关系

目的 研究血管内皮生长因子(VEGF)表达与脑膜瘤瘤周水肿(PTBE)及肿瘤复发的关系。方法 应用免疫组织化学方法检测34例脑膜瘤、3例正常脑组织中VEGF的表达情况，并与瘤周水肿、是否复发等临床情况相比较。结果正常脑组织中无VEGF表达，32／34例脑膜瘤有阳性表达，VEGF平均表达强度为1．91。VEGF表达为O的2例，平均水肿指数为O．75；VEGF表达为1的9例，平均水肿指数为l_38；VEGF。表达为2的13例，平均水肿指数为1．97；VEGF表达为3的10例，平均水肿指数为2．39；VEGF表达水平越高，瘤周水肿越明显。复发组VEGF表达(2．43)明显高于非复发组(1．55)。结论 VEGF过表达在脑膜瘤瘤周水肿的形成和肿瘤复发中起重要作用，对脑膜瘤患者预后的评估及合适治疗方案的选择有指导意义。     

Gene therapy for meningioma: improved gene delivery with targeted adenoviruses

OBJECT: Due to their surgical inaccessibility or aggressive behavior, some meningiomas cannot be cured with current treatment strategies. Gene therapy is an emerging strategy for the treatment of brain tumors, which the authors investigated to determine whether adenoviruses could be used for gene transfer in meningioma cells. METHODS: The presence of the high-affinity Coxsackievirus and adenovirus receptor (CAR) for adenovirus type 5, as well as endothelial growth factor receptor (EGFR) and alpha, integrins (ITGAVs), were analyzed in primary tumors by using immunohistochemical studies and in primary meningioma cell cultures by using fluorescence-activated cell sorting. Targeting of adenoviruses to EGFR was achieved using bispecific antibodies, whereas targeting of adenoviruses to the ITGAVs was accomplished by insertion of an RGD (arginine-glycine-aspartic acid) motif in the adenovirus fiber H1 loop. Gene transfer efficiency of untargeted and targeted vectors was compared in primary cell cultures and in spheroids derived from patients' resected tumor material. The presence of CARs was observed in all tumors and in all but one of the derived primary meningioma cells. The higher expression of EGFRs and ITGAVs indicated that these receptors could be used as alternative targets to redirect the adenoviruses. Redirection of adenoviruses to the EGFRs or integrins enhanced gene transfer threefold (range two-sevenfold) for EGFRs in primary meningioma cells and ninefold (range three-23-fold) for integrins (p = 0.002, analysis of variance). The effect of adenovirus targeting was confirmed in spheroids composed of primary meningioma cells. CONCLUSIONS: Gene transfer with adenoviruses targeted to tumor-specific receptors is very effective in primary meningioma cells and spheroids. These vectors are promising agents for gene therapy of meningiomas.     

Intraoral Perineurioma,Soft Tissue Type: Report of Five Cases,Including 3 Intraosseous Examples,and Review of the Literature

Soft tissue type perineuriomas (STP) are uncommon tumors, oral examples being very rare. They have been described in the mandible, gingiva, lips, retrotonsillar mucosa and maxillary vestibule. Herein, we report the clinicopathologic features of five STP, two affecting the buccal mucosa and three the mandible. Three patients were women and two men. All tumors were characterized by a proliferation of cytologically bland, mitotically inactive spindled cells with round, ovoid or spindled nuclei, embedded in a variably collagenous and myxoid matrix. Interestingly, two mandibular tumors featured psammoma bodies and one, in addition, contained irregular calcifications. Tumor cells showed the immunohistochemical profile of perineurial cells including epithelial membrane antigen, Glut-1, claudin-1 and collagen type IV. S100 and neurofilament proteins were not expressed by the tumor cells. A few minute, peripherally situated, entrapped nerves were identified. All tumors were reported gross-totally excised and no recurrences have taken place. The clinical characteristics of STP are summarized and its differential diagnosis relative to other spindle cells tumors and meningioma is discussed.     

A rare case of recurrent secretory meningioma with malignant transformation

A 72-year-old woman previously operated for a sphenoid-ridge meningioma, now presented with double vision. Histology showed a secretory meningioma with an epithelial-appearing, malignant component. Malignant transformation in a secretory meningioma is not known. This is the first report of such an occurrence.     

Syringocystadenoma papilliferum. A plasmacytotropic tumor

Seven cases of syringocystadenoma papilliferum were studied by immunohistochemical methods for the presence of IgG, IgA, IgM, and secretory component in tumor epithelial cells and IgG, IgA, and IgM in plasma cells underlying the tumor epithelium. Six of seven cases showed IgA positivity within epithelial cells, one case showed faint intraepithelial IgG staining, and none stained for IgM. Four of five cases were positive for secretory component. The plasma cells were predominantly of the IgG and IgA class. These findings suggest that the association of plasma cells with this tumor is a consequence of epithelial attraction via a mechanism similar to that utilized by glands of the normal secretory immune system.