Meningioma Metastasis Research Articles

Lung Adenocarcinoma to Meningioma Metastasis Revealed by an Isolated Retrobulbar Optic Neuropathy.

Lung Adenocarcinoma to Meningioma Metastasis Revealed by an Isolated Retrobulbar Optic Neuropathy.

Extracranial Meningioma Metastasis: A Systematic Review of Clinical Characteristics, Management Strategies, and Outcomes

Background: Meningioma is the most common type of intracranial neoplasm, accounting for approximately 40% of all primary brain tumors. Although these tumors are usually benign and slow-growing, extracranial metastasis can occur in less than 1% of cases. Due to the rarity, diagnosis can pose a challenge. In this systematic review, we summarize and analyze patient demographics, clinical characteristics, management strategies, and outcomes of patients with extracranial meningioma metastasis.
 Project Methods: A systematic review was performed following the (PRISMA) guidelines. PubMed, Ovid EMBASE, Cochrane, Scopus, and Web of Science databases were searched. Clinical characteristics, management, and outcomes were analyzed.
 Results: A total of 127 studies with 164 patients were included. There were 51% males and mean age of primary tumor diagnosis was 48 years (range, 8-91). Primary tumors were mostly located on the convexity of the brain (52%) and WHO grade 1 (38%) or grade 2 (37%). Histological findings were predominantly atypical (37%). Mean number of intracranial recurrences was 2 (range, 0-7) and occurred in 81% of cases. Average time between primary tumor and the first extracranial metastasis was 103 months (range, 2-450). The top three most common locations of metastases were the lungs (39%), spine (15%), and liver (12%). Most often, there was no change in grade (68%) from the primary tumor to the first metastasis. Gross total resection of the primary tumor was achieved in 76% of cases. Mean survival from primary diagnosis and survival from first metastasis was 118 and 31 months, respectively.
 Conclusion/Impact: Mechanisms by which extracranial meningioma metastasis occur are still unclear, though do not appear to involve evolution into a more aggressive histologic type in most cases. In a patient with a history of intracranial meningioma recurrence and symptoms of lung, spine, or liver, dysfunction, extracranial meningioma metastasis should be considered within the differential.

Hemorrhagic meningioma with pulmonary metastasis: Case report and literature review

Abstract Meningiomas are extra-axial neoplasms that originate from the arachnoid cap cells located on the inner surface of the meninges. Approximately 36% of central nervous system tumors are meningiomas. Based on earlier findings to be benign in most cases, they are categorized as slow-growing tumors that form gradually over time. Meningiomas are usually asymptomatic and discovered inadvertently. They rarely present with immediate clinical symptoms or abrupt hemorrhagic strokes. However, tumor hemorrhage can be fatal in high-grade meningiomas, particularly those with vascularization. We describe a 58-year-old man who was hospitalized after experiencing an unexpectedly acute headache. The right cerebellar hemisphere and vermis cerebellar hemorrhage were detected on computed tomography (CT), and the cerebellar hemorrhage was explained by a diagnosis of hypertension. When additional analysis of the patient’s chest CT indicated lung mass lesions, we assumed that the lung cancer had spread to the brain. However, the pathological outcomes of a guided definite pulmonary aspiration biopsy, in conjunction with resection of the cerebellar tumor, suggested a subtentorial meningioma with ruptured hemorrhage and pulmonary meningioma metastasis. The patient was transferred to a hospital closer to home for ongoing follow-up and, after 2 months, he had recovered well.

Metastasis of Malignant Intracranial Meningioma to the Lung: Report of a Case and Review of the Relevant Literature

Background and Importance: Distant extracranial metastasis of meningioma is rare, and the pathophysiology of metastasis in meningioma remains a topic of debate. This study aimed to describe a patient who suffered from multiple pulmonary metastases of meningioma. Case Presentation: This report introduced a rare case of a 47-year-old female who presented with right hemiparesis. Cranial Computed Tomography (CT) demonstrated a homogeneously enhanced tumor in the left temporal lobe. The patient underwent tumor resection; the pathological result was found to be World Health Organization (WHO) grade I meningothelial meningioma. Recurrence of the tumor transpired after two years and a second operation was performed. WHO grade II atypical meningioma was diagnosed. Subsequently, the patient developed a chronic cough and her chest x-ray showed multiple lung masses. CT-guided biopsy of the right lung mass was performed. Finally, pulmonary metastatic meningioma was diagnosed. Conclusion: Distant extracranial metastasis and malignant transformation of meningioma involve the genetic alteration of a tumor, which should be studied further.

Solitary pulmonary metastasis after meningioma surgery of the head: a case report

BackgroundMeningioma is the most common type of benign primary brain tumor that is rarely associated with distant metastasis. No established treatment strategy for metastatic meningiomas exists to date. Herein, we report a case of solitary pulmonary metastasis of meningioma detected 2 years after neurosurgical resection of the primary tumor.Case presentationA 75-year-old male patient underwent neurosurgical resection of a convexity meningioma (World Health Organization grade II atypical meningioma), followed by postoperative radiotherapy for the residual tumor. Two postoperative years later, a solitary 10-mm pulmonary nodule in the left lower lung lobe was detected on chest computed tomography. The patient underwent video-assisted thoracoscopic left lower lobectomy for suspected pulmonary metastasis of meningioma. The pathological diagnosis was solitary pulmonary metastasis of meningioma. No sign of further recurrence was noted at 8 months postoperatively.ConclusionsWe present a rare and unique surgical case of solitary pulmonary metastasis of meningioma. Further investigation is necessary to establish the standardized treatment strategy for metastatic meningiomas.

Metastases to cranial base meningiomas. Clinical presentations and surgical outcomes. Literature overview

Tumour-to-meningioma metastasis (TTMM) is an uncommon phenomenon, however repeatedly found in the literature. Meningiomas occur to be the most frequent target of metastatic expansion of systemic cancers. Meningiomas often vary in symptoms and treatment, and this largely depends on the tumour location. Due to their variable locations, they can be classified as convexity meningiomas, which includes falcine and parasagittal tumours, and cranial base, which includes tumours located in the olfactory groove, sphenoid wing, petrous bone and other cranial base locations. The aim of this study was to analyse all data regarding metastases to cranial base meningiomas. We performed a literature search to locate all cases of metastases to cranial base meningiomas in PubMed and Medline databases using the following key words: metastasis to meningioma, meningioma metastasis, and cranial base meningioma. We collected patient and cancer parameters, exact meningioma location and clinical presentations including characteristics which may suggest TTMM. We found 100 articles describing 111 patients of metastasis to cranial base meningioma. Among these articles, 55 cases (49.55%) included metastases to non-skull base meningiomas. In 24 cases (21.62%), the location of meningioma was not precisely described or other data were unavailable, in particular histopathological examination. The most common location of TTMM was sphenoid wing, which was found in 9 patients. The other locations included cerebellopontine angle in 5 patients, and tuberculum sellae in 3 cases. 81.25% cases of TTMM were reported in women, and the most common cancer origins were the breast (28.3%), lung (18.7%), kidney (9.38%) and prostate (9.38%). In two cases the metastatic origin was unclear, and in 15.6% of cases the patients were in remission for more than 1 year. In 78.1% of cases patients presented focal deficits, followed by increased intracranial pressure, and seizures. In almost one-third of cases, TTMM first appeared from a previously unknown cancer. Rapid clinical presentation of cranial nerve palsies may suggest the dual nature of intracranial pathology. The metastasis to cranial base meningioma should be suspected in patients with oncological background, regardless of meningioma parameters or cancer status.

Metastatic mediastinal atypical meningioma: a case report

Meningiomas are common neoplasms arising from the central nervous system meninges. Extracranial metastasis of meningiomas are rare and are usually found in less than 0.1–0.2% of cases, though isolated metastasis to the liver and lung have been reported. Because of its rarity and intriguing pathogenesis, we reported here a case of metastatic mediastinal atypical meningioma. 1.Ostrom QT, Cioffi G, Gittleman H, et al. Primary brain and other central nervous system tumours diagnosed in the US in 2012-2016. Neuro Oncol 2019; 21 (Suppl 5): v1–100.2.Miller DC, Ojemann RG, Proppe KH, et al. Benign metastasizing meningioma. Case report. J Neurosurg 1985; 62: 763–6.

Scalp Invasion by Atypical or Anaplastic Meningioma Is a Risk Factor for Development of Systemic Metastasis

Atypical and anaplastic meningiomas (AAMs) are rare and comprise approximately 5% of all meningiomas. Extracranial metastases in meningioma patients occur in 0.1% of all cases, but these lesions are difficult to treat and may be a poor prognostic factor. We conducted a retrospective chart review between 1990 and 2016 of patients who had surgical resection of AAM. In a cohort of 149 patients, 6 had metastatic lesions that were histologically confirmed to be meningioma. We compared baseline characteristics between patients with and without metastasis and performed a multivariate Cox regression analysis to assess risk factors for the development of systemic metastasis. Six patients had histologically confirmed meningioma metastasis. We hypothesized that the presence of scalp invasion in patients could be a potential risk factor for the development of systemic meningioma metastasis. Nine out of the 149 patients without metastasis had scalp invasion, whereas 4 out of the 6 patients with metastasis had scalp invasion. Patients with metastasis had a median age of 62 ± 20. Patients without metastasis had a median age of 59 ± 15 years. Gender distribution was similar; approximately 50% of patients in each group were female. Eighty-five percent of patients with metastatic disease were white, and 65% of patients without metastatic disease were white. Among patients without metastatic disease, 77% had World Health Organization II tumors, whereas 50% of patients with metastatic disease had World Health Organization II tumors. In multivariate analysis including age, tumor grade, size, location, extent of resection, sex, and scalp invasion, the only significant predictor of systemic metastasis was scalp invasion (odds ratio= 39.67; 95% confidence interval= 3.74-421.12; P= 0.0023). Median overall survival (OS) with metastasis was 126 months, and median OS without metastasis was 158 months. Having metastatic disease was not significantly associated with worse OS (P= 0.33). Metastasis development from AAM is a rare but serious event. Because scalp invasion is a strongly associated predictive factor for development of systemic metastasis in patients with AAM, it is necessary to consider strategies to prevent and to be vigilant of the development of scalp invasion.

DNA methylation profiling demonstrates superior diagnostic classification to RNA-sequencing in a case of metastatic meningioma

Meningiomas are the most common primary intracranial tumors, but meningioma metastases are rare. Accordingly, the clinical workup, diagnostic testing, and molecular classification of metastatic meningioma is incompletely understood. Here, we present a case report of multiply recurrent meningioma complicated by liver metastasis. We discuss the patient presentation, imaging findings, and conventional histopathologic characterization of both the intracranial lesion and the metastatic focus. Further, we perform multiplatform molecular profiling, comprised of DNA methylation arrays and RNA-sequencing, of six stereotactically-guided samples from the intracranial meningioma and a single ultrasound-guided liver metastasis biopsy. Our results show that DNA methylation clusters distinguish the liver metastasis from the intracranial meningioma samples, and identify a small focus of hepatocyte contamination with the liver biopsy. Nonetheless, DNA methylation-based classification accurately identifies the liver metastasis as a meningioma with high confidence. We also find that clustering of RNA-sequencing results distinguishes the liver metastasis from the intracranial meningiomas samples, but that differential gene expression classification is confounded by hepatocyte-specific gene expression programs in the liver metastasis. In sum, this case report sheds light on the comparative biology of intracranial and metastatic meningioma. Furthermore, our results support methylation-based classification as a robust method of diagnosing metastatic lesions, underscore the broad utility of DNA methylation array profiling in diagnostic pathology, and caution against the routine use of bulk RNA-sequencing for identifying tumor signatures in heterogeneous metastatic lesions.

Abstract 1806: Global analysis and validation of miRNA levels in cerebrospinal fluid of brain tumor patients

Abstract Introduction. Incidence rate of primary brain tumors and brain metastases counts yearly around 40 patients per 100 000 persons in the world and is still growing. Prognosis and therapy differs between brain tumor types and, therefore, accurate and early diagnosis might improve survival and life quality of patients. However, current diagnostic approaches are limited by localization and tissue heterogeneity of brain tumors. Cerebrospinal fluid (CSF) bathes central nervous system (CNS) and thus is supposed to reflect all pathological conditions. From this perspective, CSF looks as ideal source of diagnostic biomarkers of brain tumors. MicroRNAs, short non-coding RNAs involved in the pathogenesis of many cancers including brain tumors, might represent group of new biomarkers. In addition, dysregulated levels of brain tumor specific miRNAs have been already observed also in CSF. Following these facts, analysis of CSF miRNAs in brain tumor patients promises a new diagnostic approach enabling more accurate diagnosis. Material and methods. Next-generation sequencing was performed for analysis of small RNAs in 89 CSF samples taken from 32 GBM, 14 low-grade glioma (LGG), 11 meningioma, 13 brain metastasis patients and 19 non-tumor donors. CleanTag Small RNA Library Prep Kit (TriLink BioTechnologies) was used for cDNA library preparation. NextSeq 500 instrument together with Next 500/550 High Output v2 Kit - 75 cycles (both Illumina) were used for final sequencing analysis. Subsequently, according to NGS results we measured levels of 13 miRNAs in independent set of CSF samples (35 GBM, 42 meningiomas, 8 metastasis patients and 19 control) using TaqMan Advanced miRNA Assays (ThermoFisher Scientific). Results. NGS analysis revealed 25, 3, 2 and 14 CSF miRNAs significantly differently expressed in GBM, meningiomas, LGG and metastasis patients (p < 0.001, for LGG p < 0.05), respectively, in comparison with control CSF samples. In addition, 6 miRNAs showed different levels between GBM and LGG (p < 0.05). Subsequent validation of selected CSF miRNAs has confirmed different levels of 7 miRNAs in GBM (miR-10a, miR-196a, miR-196b, miR-30e, miR-30c, miR-7b, miR-7c), 3 in meningioma (miR-140, miR-21, miR-30e) and 2 in brain metastasis (miR-30e and miR-7c) compared to control CSF samples (p < 0.05). Validation of miRNA levels in LGG CSF samples is in progress and will be part of the poster presentation. Conclusion. We have observed that CSF from patients with various brain tumors (GBM, LGG, meningioma, and brain metastasis) is characterized by specific miRNA signature. Our results suggest potential of CSF miRNAs to be useful biomarkers in brain tumors. This work was supported by Ministry of Health of the Czech Republic grant nr. NV18-03-00398, grant of Czech Grant Agency nr. 17-17636S and by the Ministry of Education, Youth and Sports of the Czech Republic under the project CEITEC 2020 (LQ1601). Citation Format: Alena Kopkova, Jiri Sana, Marek Vecera, Tana Machackova, Pavel Fadrus, Julia Kovacova, Ondrej Slaby. Global analysis and validation of miRNA levels in cerebrospinal fluid of brain tumor patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1806.

Grade III meningioma with gastro-intestinal tract and brain metastases: case report and review of the literature

BackgroundMeningioma is the most common adult primary intracranial tumor. Malignant meningioma is a rare variant of meningioma. The prognosis for the patients with these tumors is poor, due to the tumor’s capacity for relapse and to develop distant metastases. These tumors can present the same evolutionary course as aggressive carcinoma.Case descriptionWe report the case of distant brain and gastro-intestinal tract (GIT) metastases. A 78-year-old patient developed malignant meningioma with a Ki-67 proliferative index of 40%. According to guidelines, surgery followed by postoperative radiotherapy (RT) was performed. Three months after the end of RT, he presented histologically proven meningioma distant brain and GIT metastases.ConclusionsTo our knowledge, this is the first case of meningioma GIT metastases. Also, we report the difficulty to confirm the diagnosis of meningioma metastases. Indeed, malignant meningioma has the same histopathological features as melanoma or carcinoma. The standard of care for the management of malignant meningioma is gross total surgery followed by postoperative radiotherapy. Metastatic meningioma is uncommon and no guidelines for the management of recurrent or metastatic meningioma have yet been published. However, several studies reported systemic therapeutic options such as antibody against VEGF, somatostatin analogs, PDGF-R, and VEGF-R tyrosine kinase inhibitors, in the case of recurrent or metastatic meningioma. We also made a review of the actual literature of systemic treatment options for metastatic meningioma.

Abstract 3615: Analysis of microRNAs in cerebrospinal fluid of brain tumor patients

Abstract Introduction: Cerebrospinal fluid (CSF) is a body fluid with many important functions that is in direct contact with the extracellular environment of the central nervous system (CSN). Therefore, CSF serves inter alia as a both communication channel allowing the distribution of various substances among CNS cells as well as a reservoir of waste products that these cells released. For these reasons, CSF is a potential source of diagnostic biomarkers of many neurological diseases including brain tumors. Recent studies have revealed that CSF contains also circulating microRNAs (miRNAs), short non-coding RNAs, which have been described as biofluid diagnostic markers in many cancers. The analysis of CSF miRNAs in patients affected by brain tumors could enable more precise diagnosis and patient stratification.Material and methods: We performed next-generation sequencing analysis of small RNAs (small RNAseq) in 89 CSF samples taken from 35 GBM, 14 low-grade glioma (LGG), 14 meningioma, and 8 brain metastasis patients as well as 18 non-tumor donors. Informed consent approved by the local Ethical Commission was obtained from each patient before the lumbar puncture. cDNA libraries were prepared using CleanTaq Small RNA Library Prep Kit (TriLink BioTechnologies) and, subsequently, purified by Agencourt AMPure XP (Beckman Coulter). The final sequencing analysis was performed by Next 500/550 High Output v2 Kit - 75 cycles using the NextSeq 500 instrument (both Illumina). For miRNA mapping and analysis, an online tool Chimira was used. Obtained data were subsequently statistically evaluated in the environment of statistical language R using the Bioconductor edgeR and DESeq2 package.Results: We observed 211 miRNAs to be expressed in more than 60 CSF samples with 1 395 normalized counts in average (min 3, max 77 284; miR-486-5p was excluded from analysis due to its artificial expression). From these miRNAs, 63 showed different levels in CSF of GBM, 16 in LGG, 24 in meningioma, and 31 in brain metastases patients in comparison with CSF of non-tumor donors. MiR-10a-5p and miR-196a-5p have significantly highest levels in CSF of GBM samples. Moreover, 6 miRNAs (miR-30c-5p, miR-30e-5p, miR-145-5p, miR-320c, miR-3960, and miR-6131) indicated significantly different levels between GBM and LGG (P<0.01).Conclusion: We have demonstrated that CSF of various brain tumors (GBM, LGG, meningioma, and brain metastasis) is characterized by specific miRNA signature. Moreover, we found miRNA signature with ability to differentiate LGG and GBM from CSF. Our results suggest, that after independent validations, CSF miRNAs could serve as promising biomarkers in brain tumors. This work was supported by Ministry of Health of the Czech Republic, grant nr. 15-34553A, 15-33158A, 15-31627A, 15-34678A, 16-31314A, 16-31765A and by grant of Czech Grant Agency nr. 16-18257S, 17-17636S. Citation Format: Jiri Sana, Alena Kopkova, Marek Vecera, Jaroslav Juracek, Tana Machackova, Parwez Ahmad, Natalia Anna Gablo, Pavel Fadrus, Marek Svoboda, Ondrej Slaby. Analysis of microRNAs in cerebrospinal fluid of brain tumor patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3615.

Somatic mutation landscape of a meningioma and its pulmonary metastasis

BackgroundExtracranial metastasis (ENM) of meningiomas is extremely rare, and typically occurs several years after a primary tumor is diagnosed. However, the genetic changes underlying ENM events have not yet been investigated.Case presentationA 58-year-old male patient was sent to the emergency room of our hospital because of a sudden fall. Magnetic resonance imaging detected a mass at the right frontal sagittal sinus. He underwent tumor resection and recovered well, but post-operative computed tomography revealed three lumps on the right side of his chest. Thoracic surgery was performed to remove two of the lumps. Pathological findings revealed that the brain and lung tumors were grade I meningiomas. The patient received no additional radiation or chemotherapy post-surgery, and there was no sign of tumor recurrence in the brain or progression of the remaining lump in the chest 1 year after surgery. We performed whole exome sequencing of the patient’s blood, primary brain tumor, and lung metastatic tumor tissues to identify somatic genetic alterations that had occurred during ENM. This revealed that a frameshift deletion of the neurofibromin 2 gene likely drove formation of the meningioma. Surprisingly, we found that the brain tumor was relatively homogeneous and contained only one dominant clone; both the pulmonary metastasis and the original brain tumor were derived from the same clone, and no obvious additional driver mutations were detected in the metastatic tumor.ConclusionAlthough ENM of meningiomas is very rare, brain tumor cells appear to be more adaptable to tissue microenvironments outside of the central nervous system than was commonly thought.

Disseminated Anaplastic Meningioma Before Local Recurrence

Meningiomas has account for 30% of all primary intracranial neoplasms. Extracranial meningioma metastasis is extremely rare. A 53-year-old female admitted with amnesia and headache. Subtotal resection was obtained. Tumor histopathology revealed an anapylastic meningioma and the patient received postoperative radiotherapy. Three months later, the patient experienced weakness and bone pain. Cranial MRI excluded local recurrence. Computed tomography revealed liver, bone and subcutaneous metastases. Liver biopsy confirmed the diagnosis of grade 3 meningioma. After receiving chemotherapy, CT showed progression in liver lesions and cranial MRI revealed local recurrence. The patient died 12 months after the primary surgery.

Pulmonary and pleural metastasis of intracranial anaplastic meningioma in a 3-year-old boy: A case report

In adults, meningiomas occasionally display aggressive behavior and may occasionally metastasize. By contrast, pediatric meningiomas are rare, and there is limited information regarding their clinical characteristics, treatment and prognosis. We herein report the case of a 3-year-old boy with anaplastic meningioma with a history of local recurrence and late pulmonary metastasis. At diagnosis, a 70-mm mass lesion in was identified in the right frontal lobe, with intratumoral hemorrhage. The tumor was attached to the falx cerebri and was completely resected. The histological diagnosis was anaplastic meningioma, World Health Organization grade III. Two months after the surgery, the meningioma recurred at the same site. Although the patient received radiotherapy after a second operation, the tumor metastasized to the lung and pleura 8 months after the initial operation. The metastasis was resistant to treatment, even after gross total resection, and the effectiveness of further radiotherapy was limited. The patient succumbed to the disease 1 year and 4 months after the initial diagnosis. The findings of the present case and a review of the relevant literature suggest that recurrence and metastasis of meningiomas are difficult to predict. Therefore, such patients should be carefully monitored throughout the follow-up period.

Total en bloc spondylectomy for spinal tumours: Technical aspects and surgical details

ObjectiveTo describe the specific surgical details and report the lessons learned with a series of patients suffering from spinal tumours that underwent total en bloc spondylectomy (TES). MethodsA retrospective case series review is presented, together with an analysis of the clinical and technical variables, as well as the outcomes. ResultsA total of 10 patients underwent TES (2000–2016) for primary (osteosarcoma, chondrosarcoma, fibrosarcoma and chordoma) and secondary spinal tumours (lung, breast, thyroid, oesophagus, and meningioma metastases). According to the Tomita classification, 2 patients had intra-compartmental tumours, and the rest presented as extra-compartmental. All patients experienced an improvement in their pain level after surgery. Nine patients preserved ambulation post-operatively and one patient developed paraplegia. Six patients needed subsequent operations for wound debridement, tumour recurrence, or revision of the fixation. Other complications included pneumothorax, pleural effusion and venous thrombosis. Four patients remain alive (4 months to 15 years follow-up). The rest died due to primary tumour progression (6.5 months to 12 years). A detailed description of the surgical steps, tips, and pitfalls is provided. Modifications of the technique and adjuncts to resection are commented on. Observation of some considerations (selection of candidates, careful blunt vertebral dissection, strict blood loss control, careful handling of the spinal cord, and maintenance of the radical resection concept at all stages) is key for a successful operative performance. ConclusionTES is a paradigmatic operation, in which the concept of radical resection provides functional effectiveness and improves survival in selected patients suffering from spinal tumours. Our preliminary experience allows us to highlight some specific and relevant features, especially those favouring a simpler and safer operation.

Metastasis of Meningioma: A Rare Differential Diagnosis in Subcutaneous Masses of the Scalp

Background: Subcutaneous masses of the scalp have a wide range of differential diagnosis. After removal of a meningioma in the patient’s history, scalp metastasis from the previously resected meningioma should be considered. Methods: A 86 year old patient presented with a local swelling on the left temporal forehead and no other clinical symptoms. Eleven years earlier an extra-axial meningioma was resected. The patient was receiving immunosuppressive therapy subsequent to kidney transplantation. After clinical examination and MRI, a lipoma was suspected. The mass was resected under local anesthesia. Results: Histopathology revealed a metastasis of the previously removed meningioma (WHO grade II). No further treatment was recommended. Clinical follow-up was without pathological findings so far. Conclusion: Scalp metastases of meningiomas are a rare finding. However, if patient history reveals removal of a meningioma, scalp metastasis must be a differential diagnosis for subcutaneous masses even years after the initial surgery.

Pulmonary metastasis of a meningioma presenting as a solitary pulmonary nodule: 2 case reports

Distant metastases of meningioma are rare, especially in grade 1 meningiomas. In a recent literature review, only 115 cases were found. In almost all published cases, the meningioma was treated several years before the metastasis was diagnosed. The lungs are the most frequent site of metastasis. We describe two patients treated for meningioma (one case grade 1, the other grade 3) who were referred to the Respiratory Oncology Unit because of the incidental finding of a pulmonary nodule on routine chest radiography. Both had undergone several neurosurgical procedures but the last operation was more than 7 years before in both cases. Positron emission tomography scan was suggestive of a malignant lung tumour. The lesions were surgically removed. Pathology confirmed meningioma in both cases with the same WHO grade, immunohistochemical and genetic profiles as the original meningioma. Both patients recovered well from thoracic surgery. The patient with grade 3 meningioma died three years later from intracranial recurrence. When a patient previously treated for meningioma develops a nodular lung lesion, metastasis of the meningioma should be in the differential diagnosis list. Because of the occurrence of distant metastasis even in grade I meningiomas, we suggest that the grading system should take into account genetic changes in the meningioma. Chromosome 1p and 14q losses possibly explain the aggressive behaviour of the grade 1 meningioma.

Minimally invasive resection and vertebroplasty for an osteolytic C-1 metastasis of malignant meningioma: case report.

Malignant meningiomas are a rare but aggressive subset of intracranial meningiomas leading to a very limited life expectancy. The occurrence of spinal metastases in these tumors is an even rarer event. The described patient had an intracranial malignant meningioma and developed a symptomatic osteolytic contrast-enhancing lesion in the left C-1 lateral mass suspicious for metastasis. The authors performed a minimally invasive posterior resection of the lesion with vertebroplasty of C-1. Histopathology verified metastasis of the malignant meningioma. The surgical procedure resulted in prompt and permanent pain reduction until the patient died 18 months later. Given the very limited life expectancy in this case, the authors did not consider occipitocervical fusion because of their desire to preserve the range of motion of the head. Therefore, they suggest minimally invasive tumor resection and vertebroplasty in selected palliative tumor patients.

MicroRNA-18a regulates invasive meningiomas via hypoxia-inducible factor-1α.

The aim of the present study was to investigate the effects of microRNA-18a (miR-18a) on the invasiveness and metastasis of invasive meningiomas and the underlying mechanism. A total of 69 patients with meningiomas (30 patients in the invasive meningioma group and 39 patients in the non-invasive meningioma group) and 48 cases in the control group were enrolled. Samples of meningioma tissues, serum and cerebrospinal fluid were collected. Reverse transcription-quantitative polymerase chain reaction was performed to quantify the expression levels of hypoxia-inducible factor-1α (HIF-1α) mRNA and miR-18a. Western blot analysis was used to determine protein expression levels of HIF-1α. The expression levels of HIF-1α mRNA and protein in all three types of sample from the invasive meningioma group were significantly higher compared with those in the control and non-invasive meningioma groups (P<0.05), and the expression levels of HIF-1α mRNA in the serum and cerebrospinal fluid of the non-invasive meningioma group were significantly higher compared with those in the control group (P<0.05). The expression levels of miR-18a in the invasive meningioma group were significantly reduced compared with those in the control and non-invasive meningioma groups (P<0.05), whereas the levels of miR-18a in the non-invasive meningioma group were significantly lower compared with those in the control group (P<0.05). The expression of HIF-1α is significantly upregulated in patients with invasive meningiomas, possibly due to the downregulation of miR-18a expression. Therefore, miR-18a may regulate invasive meningiomas via HIF-1α.