非典型性脑膜瘤与良性脑膜瘤MRI征象的对比分析

目的 对比分析非典型性脑膜瘤与良性脑膜瘤的MRI征象特点,提高对非典型性脑膜瘤的认识。方法 回顾性分析经病理证实的37例非典型性脑膜瘤与288例良性脑膜瘤的MRI征象。结果 非典型性脑膜瘤直径>6.5 cm比例、肿瘤呈分叶型比例、瘤脑界面不清晰比例、重度瘤周水肿比例、邻近骨质改变比例均明显高于良性脑膜瘤（P<0.05）。多因素Logistic回归分析显示,肿瘤较大及瘤脑界面不清晰为非典型性脑膜瘤的可能性显著增加,肿瘤大小每增加1.5 cm,非典型性脑膜瘤的概率是良性脑膜瘤的1.507倍,瘤脑界面不清晰为非典型性脑膜瘤的概率是良性脑膜瘤的2.605倍。结论 肿瘤大小及瘤脑界面对于非典型性脑膜瘤与良性脑膜瘤的鉴别诊断具有重要价值。     

脑膜瘤生物学特性与MRI信号特征的相关性研究

目的探讨脑膜瘤手术前MRI信号特征对手术中肿瘤生物学特性的预测价值。方法以WHO 2000年脑膜瘤病理分类为基础，追踪研究85例脑膜瘤患者，寻找肿瘤MRI信号特征与生物学特性，包括供血、质地以及瘤一脑界面是否清楚及其内在联系。结果不同病理亚型的脑膜瘤，表现出不同的MRI信号特征和生物学特性。多数良性脑膜瘤MRI信号均匀、形态规则，肿瘤周围水肿由肿瘤生长部位决定。非典型脑膜瘤MRI信号不均匀、形态不规则，肿瘤周围水肿不明显，间变型脑膜瘤周围水肿则非常明显。血管瘤型、间变型和部分非典型脑膜瘤血供丰富。微囊型、多数上皮型和多数血管瘤型脑膜瘤质地偏软，纤维型、化生型和砂粒体型则质地偏韧、硬。间变型、部分非典型和部分血管瘤型脑膜瘤的瘤一脑界面不清楚。结论脑膜瘤MRI信号特征的分析能为判断其病理亚型和生物学特性提供线索，有助于临床上制定手术策略，提高疗效。     

Anaplastic meningioma: Progression from atypical and chordoid morphotype with morphologic spectral variation at recurrence

The current WHO 2007 classification divides meningiomas into a 3‐grade prognostic hierarchy. Recent literature evokes two pathways to disease progression in meningiomas akin to a comparable paradigm in gliomas, but without similar prognostic connotation: de novo anaplastic meningioma (better prognosis), and transformed meningioma (worse prognosis). We present two adult cases of transformed meningiomas that display a spectrum of morphologic progression. Case 1 at presentation showed a random admixture of meningothelial, atypical and anaplastic meningioma. The tumor recurred as anaplastic meningioma. Case 2 presented as a chordoid meningioma, but recurred as anaplastic meningioma mainly at the invasive front in transition with residual chordoid pattern. Of interest, portions of tumor also showed papillary configuration. In accordance with the dire prognosis for anaplastic meningioma, both patients succumbed to their disease within 2 months of recurrence. The present study highlights two main points: First, that proper recognition of focal high‐grade areas in a heterogeneous low‐grade meningioma (case 1) provides critical morphologic clues to spatial histologic progression and predicts aggressive biologic behavior, as evidenced by progression to frankly anaplastic meningioma at recurrence. Second, the presence of papillary in addition to anaplastic areas, in the recurrence of a previously diagnosed chordoid meningioma supports the ostensibly heightened transforming potential of grade II meningiomas, but also reflects on the morphologic heterogeneity of high‐grade meningiomas, and their potentially diverse pathways of progression. We propose that grading of meningiomas as outlined by WHO is of more critical prognostic import than histologic sub‐typing, and must include a thorough survey of the tumor‐brain interface. Future molecular genetic correlates, akin to those characterized in gliomas, could help stratify prognostic subcategories to refine meningioma grading, and govern optimal therapeutic strategies.     

Ki‐67 proliferative index predicts clinical outcome in patients with atypical or anaplastic meningioma

Meningiomas represent the second most common central nervous system neoplasms in adults and account for 26% of all primary brain tumors. Although most are benign, between 5% and 15% of meningiomas are atypical (grade II) whereas 1–2% are anaplastic meningiomas (grade III). Although histological grade is the most relevant prognostic factor, there are some unusual cases in which establishing a diagnosis of high‐grade meningioma following 2000 World Health Organization (WHO) histological criteria is extremely difficult. Therefore, the aim of the present study was to evaluate the predictive value of Ki‐67 labeling index and its contribution to current WHO classification in predicting tumor recurrence and overall survival in patients with high‐grade meningiomas. A total of 28 patients (with 16 atypical meningiomas and 12 anaplastic meningiomas) were evaluated for demographic, clinical, radiological and therapeutic variables, and for Ki‐67 immunohistochemistry. Median Ki‐67 labeling index in the whole series was 7.0 (0.5–31.5) with no differences with respect to the histological grade (P = 0.87). In the univariate analysis, Ki‐67 labeling index and postoperative Karnofsky performance status were identified as significant prognostic factors of tumor recurrence and overall survival. The multivariate analysis demonstrated that Ki‐67 labeling index is the only independent predictor of both tumor recurrence and overall survival. More importantly, this predictive value was maintained in both patients with atypical and patients with anaplastic meningioma.     

Cytoplasmic iron deposition is associated with the expression of oxidative DNA damage marker in meningiomas

Angiomatous meningiomas are rare meningioma subtypes, which are characterized by abundant, well‐formed vessels. We encountered two cases of newly diagnosed angiomatous meningiomas exhibiting tumor cells with brown pigments, which were histochemically proven to be iron. In an attempt to understand its pathological significance, we assessed this unusual finding in representatives for each grade of meningiomas and immunoexpression of transferrin receptor (CD71) and the oxidative DNA damage marker, 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG). Iron deposition in the tumor cells was observed in 8/15 (53%) angiomatous meningioma cases, 2/6 (33%) microcystic meningiomas and 2/20 (10%) meningothelial meningiomas, which included clustered microvessels, but not in fibrous, atypical or anaplastic meningiomas (P = 0.001). Cytoplasmic CD71 expression was largely negative in angiomatous meningioma cases, but positive in meningothelial and high‐grade meningiomas, suggesting that the transferrin‐dependent iron transporter was involved in iron uptake in meningiomas. Nuclear expression of 8‐OHdG was observed in ≥50% of the tumor cells in all 15 cases of angiomatous meningioma and was associated with the presence of regressive histopathological findings, such as hyalinized vessels and cystic changes. In addition, the fraction of iron‐containing tumor cells was correlated to those expressing 8‐OHdG (P = 0.005). Our finding indicates that cytoplasmic iron deposition in tumor cells is characteristic of highly vascularized benign meningiomas and related to increased oxidative DNA damage markers.     

Intraventricular metaplastic meningioma in a child: case report and review of the literature

Childhood meningiomas are rare and display important differences from adult forms. We report the first case of an intraventricular metaplastic meningioma arising in a child. A 7‐year‐old female underwent resection of an enhancing tumor arising within the left lateral ventricle. It was composed of monomorphic cells embedded within an abundant myxoid stroma. The cells demonstrated epithelial membrane antigen and vimentin immunoreactivity. Ultrastructural analysis demonstrated intermediate filaments, complex intercellular interdigitations and desmosomes, and a diagnosis of myxoid (metaplastic) meningioma was rendered. This case reflects the higher incidence of intraventricular meningiomas in childhood and greater incidence of intraventricular meningiomas in the left lateral ventricle. Recognition of the grade I myxoid meningioma in this case is paramount since chordoid meningiomas, which share similar histologic features, are of a higher grade and worse prognosis.     

Xanthomatous changes in atypical and anaplastic meningiomas. Light and electron microscopic investigations

Xanthomatous changes may occur in meningiomas of different histological type, however their incidence in combination with histological features of atypical or anaplastic meningioma has not been previously documented. In this report we present clinicopathologic, immunohistochemical and ultrastructural studies in the surgical cases of two atypical and three anaplastic meningiomas exhibiting prominent xanthomatous changes. In all tumors the xanthomatous cells were seen in association with typical meningioma structures such as meningothelial whorls or psammoma bodies as well as within the tumor parts displaying pleomorphism, patternless growth, increased cellularity, presence of necroses and mitoses or brain invasion. Ultrastructural study revealed a wide-range of lipid-containing cells, reflecting a continuum of gradual transition between polymorphic meningioma cells and xanthomatous cells. Commonly, the lipidized cells exhibited different degrees of plasmalemmal interdigitations and desmosomal junctions. Our study allowed us to confirm the meningothelial origin of xanthomatous cells in atypical and anaplastic meningiomas. Moreover, the ultrastructural observations of lysosomes in the majority of xanthomatous cells and the immunoreactivity for the CD68 antigen indicated their macrophage characteristics. It seems that a mixed meningeal/macrophage nature of xanthomatous cells can be related to the functional and structural multipotentiality of the primary leptomeningeal cells.     

Gain of chromosome arm 1q in atypical meningioma correlates with shorter progression-free survival

M. Jansen, G. Mohapatra, R. A. Betensky, C. Keohane and D. N. Louis (2012) Neuropathology and Applied Neurobiology 38, 213–219 Gain of chromosome arm 1q in atypical meningioma correlates with shorter progression‐free survival Aims: Atypical (World Health Organization grade II) meningiomas have moderately high recurrence rates; even for completely resected tumours, approximately one‐third will recur. Post‐operative radiotherapy may aid local control and improve survival, but carries the risk of side effects. More accurate prediction of recurrence risk is therefore needed for patients with atypical meningioma. Previously, we used high‐resolution array comparative genomic hybridization to identify genetic variations in 47 primary atypical meningiomas and found that approximately 60% of tumours show gain of 1q at 1q25.1 and 1q25.3 to 1q32.1 and that 1q gain appeared to correlate with shorter progression‐free survival. This study aimed to validate and extend these findings in an independent sample. Methods: Eighty‐six completely resected atypical meningiomas (with 25 recurrences) from two neurosurgical centres in Ireland were identified and clinical follow‐up was obtained. Utilizing a dual‐colour interphase fluorescence in situ hybridization assay, 1q gain was assessed using Bacterial Artificial Chromosome probes directed against 1q25.1 and 1q32.1. Results: The results confirm the high prevalence of 1q gain at these loci in atypical meningiomas. We further show that gain at 1q32.1 and age each correlate with progression‐free survival in patients who have undergone complete surgical resection of atypical meningiomas. Conclusions: These independent findings suggest that assessment of 1q copy number status can add clinically useful information for the management of patients with atypical meningiomas.     

Two cases of atypical meningioma with pulmonary metastases: A comparative cytogenetic analysis of chromosomes 1p and 22 and a review of the literature

We present two cases of atypical meningioma WHO grade II with a history of multiple local recurrences and late pulmonary metastases. Comparative cytogenetic analyses on 1p and 22q confirmed clonal origin of the primary intracranial meningiomas and the pulmonary metastases in both cases. These cases illustrate the importance of close neuroradiological follow‐up to detect tumor recurrence in patients with atypical meningiomas WHO grade II even with clinically stable disease and should sensitize clinicians to late extracranial metastases of these tumors, especially to the lung. In an effort to elucidate common clinical features of metastatic meningiomas, especially to the lung, the literature was reviewed from 1995 to 2014, identifying a total of 45 published cases.     

Two cases of primary osteolytic intraosseous meningioma of the skull metastasizing to whole skull and the spine

We report here two cases of primary intraosseous meningioma with aggressive behavior. A 68-year-old man presented with a one year history of a soft, enlarging mass in the right parietal region. Magnetic resonance image (MRI) revealed a 6 cm sized, heterogeneously-enhancing, bony expansile mass in the right parietal bone, and computed tomograph (CT) showed a bony, destructive lesion. The tumor, including the surrounding normal bone, was totally resected. Dural invasion was not apparent. Diagnosis was atypical meningioma, which extensively metastasized within the skull one year later. A 74-year-old woman presented with a 5-month history of a soft mass on the left frontal area. MRI revealed a 4 cm sized, multilobulated, strongly-enhancing lesion on the left frontal bone, and CT showed a destructive lesion. The mass was adhered tightly to the scalp and dura mater. The lesion was totally removed. Biopsy showed a papillary meningioma. The patient refused adjuvant radiation therapy and later underwent two reoperations for recurred lesions, at 19 and at 45 months postoperative. The patient experienced back pain 5 years later, and MRI showed an osteolytic lesion on the 11th thoracic vertebra. After her operation, a metastatic papillary meningioma was diagnosed. These osteolytic intraosseous meningiomas had atypical/malignant pathologies, which metastasized to whole skull and the spine.     

Intracranial mesenchymal chondrosarcoma with osteoid formation: report of a pediatric case

CASE REPORT: We present a case of a 14-year-old girl with a 3-week history of severe progressive headache and intermittent vomiting. Magnetic resonance imaging (MRI) revealed a large intensely enhancing mass, which seemed to arise from the right side of the cerebral fossa with implant base in the inferior face of the tentorium and significant mass effect on the nearby structures. A presumptive preoperative diagnosis of meningioma was made. Subtotal surgical resection was performed using the occipital approach. Histologically the neoplasms had the classic features of a mesenchymal chondrosarcoma associated with the focal presence of osteoid matrix. DISCUSSION: Clinical features, therapeutic approaches and prognosis of this rare tumour are discussed with regard to the known 30 cases in the literature.     

Meningioma of the cavernous sinus in a child

Intracranial meningiomas in children are rare, representing 1–4.2% of central nervous system tumors and 1.5–1.8% of all intracranial meningiomas. Meningiomas arising from the lateral wall of the cavernous sinus account for less than 1% of all intracranial meningiomas. To our knowledge, only one case of a meningioma arising from the cavernous sinus has been reported in childhood. A 6-year-old boy presented with left ophthalmoplegia. A slight drooping of the left eyelid was noted at the age of 1 year. Magnetic resonance imaging (MRI) with contrast administration revealed an enhancing mass lesion located in the left cavernous sinus. The tumor, arising from the lateral wall of the cavernous sinus, was totally removed and the oculomotor nerve was reconstructed with a sural nerve graft. MRI displayed total tumor removal 1 month after the surgery. The pathological diagnosis was of a psammomatous meningioma. Received: 6 March 1998 Revised: 14 July 1998     

Atypical meningioma: a clinicopathological analysis

In this retrospective study, 382 operated cases of meningiomas were reviewed. 32 cases (8.3%) were histopathologically classified as atypical meningioma. The anatomical locations and histological features in all the thirty-two cases were correlated with their recurrence rates and biological behaviour. The overall recurrence rate for atypical meningioma within two years was 28% as compared to 9.3% in benign meningiomas. It is being emphasized that an accurate histopathological interpretation of atypical meningioma is essential for predicting the recurrence, biological behavior as well as post-operative management modalities.     

Chordoid meningioma: Rare variant of meningioma

Chordoid meningioma is a rare variant of meningioma that bears a striking histological resemblance to chordoma and has greater likelihood of recurrence. Although most meningiomas occur in the intracranial, orbital and intravertebral cavities, rare meningiomas have been reported in extracranial organs; thus, it is important to be able to distinguish them from other neoplasms that have similar histology but different biological behavior and therapies. A case of chordoid meningioma in a 48‐year‐old woman who did not have Castleman's syndrome is described in the present report. The patient presented with a mass in her left frontoparietal region, and had been suffering from headaches for many years. Magnetic resonance imaging of the brain demonstrated an expansive lytic lesion in the squamous portion of the left temporal bone. The lesion extended in both directions. Histological examination of the surgical specimen revealed a tumor composed of cords and nests of eosinophilic vacuolated cells embedded in a myxoid matrix. A typical meningiomatous pattern was observed focally, and positive staining of the tumor cells for vimentin and epithelial membrane antigen confirmed the diagnosis of chordoid meningioma.     

Fourth ventricular meningioma: a case report and literature review

A 60-year-old man was admitted with slowly progressive dizziness. Cranial nerve evaluation found no abnormalities. Magnetic resonance imaging revealed a well-circumscribed mass with homogeneous enhancement located in the fourth ventricle. The patient underwent surgery for the removal of the tumor via the bilateral suboccipital approach. Subtotal removal of the tumor was achieved in a piecemeal fashion. Histological diagnosis was meningothelial meningioma. Fourth ventricular meningiomas are extremely rare. We reviewed the literature and discussed the features of fourth ventricular meningiomas.     

Childhood radiation‐associated atypical meningioma with novel complex rearrangements involving chromosomes 1 and 12

Meningiomas are recognized as the most common late complication following radiotherapy. However, cytogenetic studies in childhood atypical radiation‐induced meningioma are sporadic, mainly because this condition generally occurs after a long latent period. In the present study we show the results of conventional and molecular cytogenetics in a 14‐year‐old boy with a secondary atypical meningioma. Apart from numerical changes, we found complex aberrations with the participation of chromosomes 1, 6 and 12. The invariable presence of loss of 1p was demonstrated by fluorescent in situ hybridization (FISH) analysis with probes directed to telomeric regions and by comparative genome hybridization (CGH). Previous cytogenetic studies on adult spontaneous and radiation‐associated meningiomas showed loss of chromosome 22 as the most frequent change, followed by loss of the short arm of chromosome 1. To the best of our knowledge this is the first report of highly complex chromosome aberrations in the pediatric setting of meningioma.     

Tumor‐to‐tumor metastasis to the central nervous system

Tumor‐to‐tumor metastasis is a well‐recognized phenomenon. Meningioma is the most common intracranial host tumor, with the breast and lung being the most common primary sites. We report herein two such cases of metastasis from pulmonary adenocarcinoma and malignant melanoma (MM) of vulva, respectively. Case 1: a 69‐year‐old female smoker who had a history of right upper lobectomy of lung for adenocarcinoma presented with a headache and altered mental status, and was found to have a left temporal contrast‐enhancing mass with massive surrounding edema on MRI. The resection specimen revealed foci of metastatic adenocarcinoma within a microcystic meningioma. Case 2: a 75‐year‐old woman with a history of radical vulvectomy for MM died of widespread systemic metastasis of MM. At autopsy, a 2.5 × 2 × 2 cm firm nodule attached to the falx was incidentally found, with focal black discoloration at the periphery of the mass. Histologic examination showed a fibroblastic meningioma with a focus of metastatic MM. Case 1 is the first case report describing a microcystic variant of meningioma harboring metastatic carcinoma. Although MM is one of the most common metastatic brain tumors, MM‐to‐meningioma metastasis is reportedly extremely rare, but can occur.     

Immunocytochemical analysis of glucose transporter protein‐1 (GLUT‐1) in typical,brain invasive,atypical and anaplastic meningioma

Glucose transporter‐1 (GLUT‐1) is one of the major isoforms of the family of glucose transporter proteins that facilitates the import of glucose in human cells to fuel anaerobic metabolism. The present study was meant to determine the extent of the anaerobic/hypoxic state of the intratumoral microenvironment by staining for GLUT‐1 in intracranial non‐embolized typical (WHO grade I; n = 40), brain invasive and atypical (each WHO grade II; n = 38) and anaplastic meningiomas (WHO grade III, n = 6). In addition, GLUT‐1 staining levels were compared with the various histological criteria used for diagnosing WHO grade II and III meningiomas, namely, brain invasion, increased mitotic activity and atypical cytoarchitectural change, defined by the presence of at least three out of hypercellularity, sheet‐like growth, prominent nucleoli, small cell change and “spontaneous” necrosis. The level of tumor hypoxia was assessed by converting the extent and intensity of the stainings by multiplication in an immunoreactive score (IRS) and statistically evaluated. The results were as follows. (1) While GLUT‐1 expression was found to be mainly weak in WHO grade I meningiomas (IRS = 1–4) and to be consistently strong in WHO grade III meningiomas (IRS = 6–12), in WHO grade II meningiomas GLUT‐1 expression was variable (IRS = 1–9). (2) Histologically typical, but brain invasive meningiomas (WHO grade II) showed no or similarly low levels of GLUT‐1 expression as observed in WHO grade I meningiomas (IRS = 0–4). (3) GLUT‐1 expression was observed in the form of a patchy, multifocal staining reaction in 76% of stained WHO grade I‐III meningiomas, while diffuse staining (in 11%) and combined multifocal and areas of diffuse staining (in 13%) were only detected in WHO grades II and III meningiomas, except for uniform staining in angiomatous WHO grade I meningioma. (4) “Spontaneous” necrosis and small cell change typically occurred away from the intratumoral capillary network embedded within the pattern of GLUT‐1 staining. Taken together, GLUT‐1 staining cannot be applied as a substitute for histologic grading in order to predict tumor behavior. However, assessment of tumor hypoxia in association with “spontaneous” necrosis and foci of small cell change may substantially contribute to the neuropathologic diagnosis of WHO grades II and III meningioma.     

Extracranially extended meningothelial meningiomas with a high MIB‐1 index: A report of two cases

Meningiomas that extend from the meninges to the extracranial tissue and result in skull osteolysis have been known to take an aggressive clinical course. Two such cases in elderly patients are reported. Case 1 is an 82‐year‐old woman who had undergone removal of the parasagittal meningioma (meningothelial meningioma with 5% of MIB‐1 index) 4 years and 6 months previously, developed recurrence of the tumor that extended to extracranial soft tissue. Biopsy obtained from the subcutaneous tissue showed an atypical meningothelial meningioma with 20% of MIB‐1 index. In case 2 an 84‐year‐old man, who developed rapidly progressing dementia and gait disturbance, the MRI study revealed an intracranial‐extraaxial right frontal tumor with an extracranial extension resulting in skull osteolysis. Pathological examination of the totally resected tumor identified meningothelial meningioma, but MIB‐1 index of the intracranial portion of the tumor was less than 0.1%, while that of the extracranial portion was approximately 15%. Although the meningiomas presently reported failed to show histological features of malignancy, the high MIB‐1 index indicated that they were rapidly growing tumors. In the present report it is considered that meningioma cells that invade the skull and extracranial tissue are biologically aggressive and require total resection, as long as the condition of the patients is feasible for surgery.     

Diffusion-weighted imaging predicts postoperative persistence in meningioma patients with peritumoural abnormalities on magnetic resonance imaging.

OBJECTIVE: While diffusion-weighted magnetic resonance imaging (MRI) has been used to study malignant brain tumours, this modality has not been used to study MRI abnormalities surrounding meningiomas. METHODS: We examined intensity and apparent diffusion coefficient (ADC) on diffusion weighted imaging (DWI) for predicting postoperative persistence of MRI abnormalities surrounding meningiomas as well as characterizing the tumours. RESULTS: Of 36 meningiomas who underwent gross total resection, 27 (75%) showed hyperintensity on DWI at b=1100s/mm(2). No atypical meningiomas were hypointense on DWI. Of the 26 supratentorial meningiomas, 18 (69.0%) had associated MRI abnormality. No significant correlation was seen between tumour intensity on DWI and existence of surrounding MRI abnormality. Meningothelial meningiomas showed a relatively low prevalence of MRI abnormalities surrounding tumour (30%). Of 11 patients who underwent sequential MRI, all MRI abnormalities surrounding tumour showing isointensity and high ADC on preoperative DWI disappeared after surgery (from 3 weeks to 10 months). All MRI abnormalities surrounding tumour showing hyperintensity and low ADC on preoperative DWI persisted on final follow-up MRI (from 6 months to 20 months). CONCLUSION: The postoperative course of MRI abnormality surrounding tumour might be predictable from the intensity and ADC on preoperative DWI. Since MRI abnormalities associated with meningiomas can cause preoperative neurologic deficits. We hypothesise that abnormalities with restricted diffusion will be more likely to be associated with a preoperative deficit, and more likely to remain after removal of the causative meningioma.