Metastatic Atypical and Anaplastic Meningioma: A Case Series and Review of the Literature

Recurrent subcutaneous metastasis of a convexity meningioma: a case report and literature review

Subcutaneous metastasis in the operative route after intracranial meningioma resection is extremely rare. Here we describe the case of a 69-year-old male who was operated on in our department for a convexity meningioma that spread a few years after surgery in the soft tissues next to the craniotomy site. Twenty-one other cases have been found in the medical literature. In this article, we discuss mechanisms of growth, presentation and management of subcutaneous meningiomas.

A case of multiples liver metastases from a grade 2 brain meningioma: a rare entity with comprehensive literature review

Introduction and importance

Meningiomas are primary benign extra-axial central nervous system neoplasms that originate in meningothelial cells. Extra-neurological metastases are quite rare and occur in 0.1% of cases. The main metastatic sites are usually the lungs, bones, pleura, mediastinum and lymph nodes. Hepatic locations are quite rare and account for ~3% of all extracranial metastases. The dissemination route is still a subject of debate. Suggested routes of dissemination include the venous system, lymph nodes, or even cerebrospinal fluid. The treatment is based on complete surgical excision or on radiosurgery and adjuvant radiotherapy in case of subtotal resection.

Case presentation

The authors present the following clinical case of a 31-year-old healthy male patient with surgical history of meningioma excisions, who presents, 3 years later, evidence of liver masses on tomography and confirmed diagnosis of liver metastases from brain meningioma after biopsy with favorable outcomes after chemotherapy.

Clinical discussion

The overall incidence of extra-neurological metastases of meningiomas remains low. The vast majority of these metastases concern those of high grade, namely WHO grade 2 and 3 as it was reported in our case. Hepatic metastases remain quite rare and account for ~3% of all extracranial locations. Due to these characteristics of having low recurrence and its rare frequency of metastasis to extracranial sites, the authors, through their case, will dig into the literature to dissect this rare entity.

Conclusion

In the report of liver lesions, the first differential diagnosis in mind should be metastatic lesions, if there is a prior clinical history of primary tumors.

Challenging diagnosis and management of anaplastic meningioma in a pediatric patient: A case report

This case report highlights the diagnostic and therapeutic journey of a 16-year-old female presenting with chronic headaches, ultimately diagnosed with anaplastic meningioma. Despite its rarity in pediatric patients, anaplastic meningioma necessitates swift recognition and management due to its aggressive nature. Imaging findings, including CT and MRI, initially suggested a provisional diagnosis of hemangiopericytoma, emphasizing the diagnostic challenge posed by this condition. Surgical intervention revealed unexpected histopathological findings, highlighting the importance of thorough evaluation. Treatment involved frontal craniectomy and excision followed by adjuvant radiotherapy. While the patient's postoperative course was uneventful, histopathology confirmed the presence of anaplastic meningioma, leading to the adjustment of her clinical management. This case shows the need for heightened suspicion and comprehensive evaluation in similar presentations to facilitate timely intervention and improve patient outcomes.

Metastasis of Intracranial Meningioma to the Osseous Spine: Systematic Literature Review and Case Report

BACKGROUND

Osseous spinal metastases from intracranial meningiomas are rare but represent a serious disease progression. A literature review was performed on this topic to understand the clinical course of patients with this disease entity. We also present a case of spinal metastasis in a patient with a World Health Organization grade III meningioma.

METHODS

The PubMed/MEDLINE database was queried on August 15, 2021, using the keywords (meningioma) AND (metastasis) AND (vertebra∗ OR spin∗). All publications reporting outcomes of patients with meningioma metastatic to the spine were included. Disease characteristics, treatment modality, and outcomes were extracted from each study. Because data availability varied widely between studies, no meta-analysis was performed.

RESULTS

A total of 30 articles with 33 cases were included. Outcome data varied greatly in terms of quality and length of follow-up. Of 28 cases with reported outcomes data, 20 resulted in patient mortality ranging from a few weeks to 5 years after spinal metastasis. Mean (standard deviation) survival time was 5.8 (6.4) years following initial diagnosis, but only 1.4 (3.2) years from spinal metastasis. The longest survivor was noted to have no recurrence of disease 4 years after spinal metastasis.

CONCLUSIONS

Bony spinal metastasis from intracranial meningioma is an extremely rare occurrence. Within the limits of the available literature, outcomes of patients with this disease appear to be poor. However, data reporting is inconsistent, and several articles did not report any outcome data. Further study is needed to better clarify the course and prognosis of this disease.

The Natural History and Treatment of Meningiomas: An Update

Meningiomas are the most frequent nonmalignant tumors of the central nervous system (CNS). Despite their benign nature and slow-growing pattern, if not diagnosed early, these tumors may reach relatively large sizes causing significant morbidity and mortality. Some variants are located in hard-to-access locations, compressing critical neurovascular structures, and making the surgical management even more challenging. Although most meningiomas have a good long-term prognosis after treatment, there are still controversies over their management in a subset of cases. While surgery is the first-line treatment, the use of fractionated radiotherapy or stereotactic radiosurgery is indicated for residual or recurrent tumors, small lesions, and tumors in challenging locations. Advances in molecular genetics and ongoing clinical trial results have recently helped both to refine the diagnosis and provide hope for effective biomolecular target-based medications for treatment. This article reviews the natural history and current therapeutic options for CNS meningiomas.

Hemorrhagic meningioma with pulmonary metastasis: Case report and literature review

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.

Reconstruction of Moderately and Severely Atrophic Scalp-A Multicentric Experience in Surgical Treatment of Patients Irradiated for Tinea Capitis in Childhood and Surgical Algorithm

Background and Objectives: Before the introduction of griseofluvin, the use of X-ray radiation was the treatment of choice for tinea capitis. More than half a century later various types of tumors have been found to be associated with childhood irradiation due to tinea capitis, most commonly cancers of the head and neck, as well as brain tumors. The often unusually aggressive and recurrent nature of these tumors necessitates the need for repeated surgeries, while the atrophic skin with an impaired vascular supply due to radiation often poses an additional challenge for defect reconstruction. We present our experience in the surgical treatment of such patients. Materials and Methods: This is a retrospective cohort study. In this study, 37 patients treated for acquired defects of the scalp with a history of irradiation therapy due to tinea capitis in childhood were included in this study, 24 male and 13 female patients. The mean age at the first appointment was 60.6 ± 7.8, with the youngest included patient being 46 and the oldest being 75 years old. Patients' characteristics, surgical treatment, and complications were analyzed and a reconstructive algorithm was developed. Results: Local flaps were used for reconstruction in 34 patients, direct sutures were used in 10 patients and 20 patients received split-thickness skin grafts for coverage of both primary and secondary defects for reconstruction of flap donor sites. One regional flap and one dermal substitute covered by an autologous skin graft were also used for reconstruction. Complications occurred in 43.2% of patients and were significantly associated with the presence of comorbidities (p = 0.001), aseptic bone necrosis (p = 0.001), as well as skin atrophy in frontal, occipital, and parietal region (p = 0.001, p = 0.042 and p = 0.001, respectively). A significant correlation between major complications and moderate skin atrophy was found only in the parietal region (p = 0.026). Conclusions: Unfortunately, many protocols developed for scalp reconstruction are not applicable in the setting of severe or diffuse scalp skin atrophy associated with high tumor recurrence rate and radiation-induced vascular impairment, such as in tinea capitis patients in Serbia. An algorithm has been developed based on the authors' experience in managing these patients.

Intracranial meningiomas: an update of the 2021 World Health Organization classifications and review of management with a focus on radiation therapy

Meningiomas account for approximately one third of all primary intracranial tumors. Arising from the cells of the arachnoid mater, these neoplasms are found along meningeal surfaces within the calvarium and spinal canal. Many are discovered incidentally, and most are idiopathic, although risk factors associated with meningioma development include age, sex, prior radiation exposure, and familial genetic diseases. The World Health Organization grading system is based on histologic criteria, and are as follows: grade 1 meningiomas, a benign subtype; grade 2 meningiomas, which are of intermediately aggressive behavior and usually manifest histologic atypia; and grade 3, which demonstrate aggressive malignant behavior. Management is heavily dependent on tumor location, grade, and symptomatology. While many imaging-defined low grade appearing meningiomas are suitable for observation with serial imaging, others require aggressive management with surgery and adjuvant radiotherapy. For patients needing intervention, surgery is the optimal definitive approach with adjuvant radiation therapy guided by extent of resection, tumor grade, and location in addition to patient specific factors such as life expectancy. For grade 1 lesions, radiation can also be used as a monotherapy in the form of stereotactic radiosurgery or standard fractionated radiation therapy depending on tumor size, anatomic location, and proximity to dose-limiting organs at risk. Optimal management is paramount because of the generally long life-expectancy of patients with meningioma and the morbidity that can arise from tumor growth and recurrence as well as therapy itself.

Case Report: Recurrent meningioma with multiple metastases

Post-surgery recurrence of meningiomas with multiple extracranial metastases is rare. Currently, information on extracranial metastases is limited, and no clear predictors and standardized treatment protocols can be applied clinically. Herein, we report a case of meningioma that recurred after two surgeries and had multiple distant metastases. Computed tomography revealed multiple enlarged lymph nodes in the para-aortic arch, left lower lung region, retroperitoneum, and abdominopelvic region, as well as soft tissue mass-like lesions under the liver capsule in the right lobe of the liver. Magnetic resonance imaging showed space-occupying lesions under the cranial plate of the left parietal lobe. Tissue biopsy confirmed the diagnosis of recurrent meningioma with extracranial metastases. Immune checkpoint inhibitors and anti-angiogenic drugs were administered. After two treatment cycles, the patient's clinical symptoms were significantly relieved, and the imaging assessment confirmed a stable disease. Although it did not meet our expectations, this combination therapy still demonstrated a possible benefit in improving meningioma patients' survival and quality of life. In this report, along with the case, we also review the relevant literature on the subject and discuss the associated risk factors and treatment options.

Multidisciplinary approach to anaplastic and metastatic meningioma: A case report and review of the literature

BACKGROUND

Meningiomas are slow-growing neoplasms, accounting for 20% of all primary intracranial neoplasms and 25% of all intraspinal tumors. Atypical and anaplastic meningiomas are infrequent, representing fewer than 5% of all meningiomas. Unusually, they can show aggressive behavior, and extracranial metastases are extremely rare, representing approximately 0.1% of all reported cases.

CASE DESCRIPTION

Fifty-six-year-old male patient diagnosed with atypical basal frontal meningioma with multiple resections, both endoscopic endonasal and transcranial. After hypofractionated radiosurgery, the patient showed new tumor recurrence associated to right cervical level II ganglionic metastasis. We opted for complete resection of the meningioma and reconstruction with anterior rectus abdominis muscle flap, as well as selective cervical ganglionectomy. Anatomical pathology showed neoplastic proliferation of meningothelial cells in syncytial cytoplasm, oval or spherical nuclei with slight anisocariosis and hyperchromasia, and intranuclear vacuoles, all compatible with anaplastic meningioma.

CONCLUSION

Due to a lack of consensus on how to treat a metastatic malignant meningioma, this pathology requires a multidisciplinary approach, and treatment needs to be adapted to each particular case. Complete resection of the lesion is the primary goal, and this requires complex procedures involving endocranial as well as extracranial surgeries, which result in composite defects difficult to resolve. Microvascular free flaps are considered the gold standard in reconstructions of large skull base defects, with high success rates and few complications.

Meningiomas with CNS invasion

CNS invasion has been included as an independent criterion for the diagnosis of a high-grade (WHO and CNS grade 2 and 3) meningioma in the 2016 and more recently in the 2021 WHO classification. However, the prognostic role of brain invasion has recently been questioned. Also, surgical treatment for brain invasive meningiomas may pose specific challenges. We conducted a systematic review of the 2016-2022 literature on brain invasive meningiomas in Pubmed, Scopus, Web of Science and the Cochrane Library. The prognostic relevance of brain invasion as a stand-alone criterion is still unclear. Additional and larger studies using robust definitions of histological brain invasion and addressing the issue of sampling errors are clearly warranted. Although the necessity of molecular profiling in meningioma grading, prognostication and decision making in the future is obvious, specific markers for brain invasion are lacking for the time being. Advanced neuroimaging may predict CNS invasion preoperatively. The extent of resection (e.g., the Simpson grading) is an important predictor of tumor recurrence especially in higher grade meningiomas, but also - although likely to a lesser degree - in benign tumors, and therefore also in brain invasive meningiomas with and without other histological features of atypia or malignancy. Hence, surgery for brain invasive meningiomas should follow the principles of maximal but safe resections. There are some data to suggest that safety and functional outcomes in such cases may benefit from the armamentarium of surgical adjuncts commonly used for surgery of eloquent gliomas such as intraoperative monitoring, awake craniotomy, DTI tractography and further advanced intraoperative brain tumor visualization.

Surgical management of a giant hepatic metastasis from a cranial meningioma 10 years after resection

Meningiomas are the most common type of primary brain tumor; they have a low risk for extracranial metastases, which are primarily associated with increased tumor grade. Hepatic metastases from cranial meningiomas are extremely rare, with only a paucity of cases reported in the literature and no standardized approach to management. Herein, we report a case of an incidentally discovered giant (>20 cm) metastatic meningioma to the liver treated with surgical resection 10 years following resection of a low-grade cranial meningioma. This report also highlights the use of (68Ga) DOTATATE PET/CT as the diagnostic imaging modality of choice when evaluating for meningioma metastases. To our knowledge, this report describes the largest hepatic metastasis from a cranial meningioma to undergo surgical resection in the literature.

Intracranial arteriovenous malformation (AVM) or meningothelial meningioma (MM)? Outlining the similarities and differences on imaging studies for an accurate diagnosis, case report

INTRODUCTION AND IMPORTANCE

AVM and MM represent neurosurgical challenges, not only when involving eloquent brain, but also by posing a significant intraoperative haemorrhagic risk. It is a challenge in itself to establish a proper differential diagnosis between the two lesions, especially since they require distinct interventional plan of action. We present the case of a patient initially diagnosed by specialists with an intracranial AVM, which was revealed intraoperatively to be in fact an MM.

CASE PRESENTATION

A 29-years patient, transferred to our department by urgency. The patient symptoms started two weeks prior admission with severe headache and vomiting. A cerebral computer tomographic angiography (CTA) was performed and interpreted by radiologists, as a large left frontal AVM.

CLINICAL DISCUSSION

Upon through review the majority of surgical team believed the mass to be AVM. However, during surgery it turned out to be Meningioma. The patient underwent a left pterional craniotomy with removal of the tumour, classified as Simpson grade II. The pathological exam confirmed the lesion to be an MM.

CONCLUSIONS

Acquiring neuro-radiological expertise is vital for the neurosurgeon, as well as fast ability for adjusting the initial action plan with the intraoperative discoveries. An experienced eye can benefit the patient by obtain a correct diagnosis in most difficult cases.

68Ga-DOTATOC PET in Extracranial Hepatic and Bone Metastasis of Atypical Refractory Meningioma: A Case Report

ABSTRACT

A falcine meningioma was diagnosed in a 66-year-old woman and was treated by surgery and 2 times by radiotherapy during 9 years of follow-up with the diagnosis of atypical meningioma. Three months after the last radiotherapy, incidental liver lesions were detected on chest CT realized for suspected pneumonia. In view of the predisposing factors for meningioma metastases, 68Ga-DOTATOC hepatic and cerebral PET/MRI was performed and completed by total body PET/CT demonstrating a somatostatin receptor 2 overexpression of the multiple liver lesions and several bone lesions. Biopsies from the liver and iliac bone confirmed the metastatic origin of meningioma.

Mutational signature of extracranial meningioma metastases and their respective primary tumors

Extracranial metastases of intracranial meningiomas are rare. Little is known about the mutational pattern of these tumors and their metastatic seeding. Here, we retrospectively explored the molecular alterations of these metastatic lesions and their respective intracranial tumor manifestations.Histology and genome sequencing were performed in intracranial meningiomas and their extracranial metastatic lesions operated upon between 2002 and 2021. Next-generation DNA/RNA sequencing (NGS) and methylome analysis were performed to determine molecular alterations.We analyzed the tumors of five patients with clinically suspected metastases of a meningioma using methylome analysis and next generation panel sequencing of the primary tumors as well as the metastatic lesions. Metastases were found in the spinal cord and one in the lung. In four of these patients, molecular analyses confirmed metastatic disease, while the fifth patient was found to harbor two molecularly distinct meningiomas. On pathological assessment, the primary lesions ranged from CNS WHO grades 1 to 3 (integrated molecular-morphologic meningioma classification scores 2 to 6). Of the four true metastatic cases, three out of the four metastasizing tumors harbored alterations in the BAP1 gene, comprising a stop-mutation combined with copy-number loss (WHO grade 1), copy number loss (WHO grade 3) and a frameshift mutation (WHO grade 2). Furthermore, the latter was confirmed to harbor a BAP1 tumor predisposition syndrome. The fourth metastasizing tumor had copy-number losses in NF2 and PTEN. Only one of four showed CDKN2A homozygous deletion; none showed TERT promotor mutation.Our results molecularly confirm true metastatic disease in four meningioma patients. BAP1 gene alterations were the most frequent. Larger cohorts, most likely from multicenter studies are necessary to evaluate the role of BAP-1 alterations to further understand the metastatic spread in meningiomas. for metastatic spread and might indicate patients at risk for metastatic spread. Further explorations within larger cohorts are necessary to validate these findings which might influence the clinical management in the future.

Brain Invasion and Trends in Molecular Research on Meningioma

Meningiomas are the most common primary brain tumors in adults. The treatment of non-benign meningiomas remains a challenging task, and after the publication of the 2021 World Health Organization classification, the importance of molecular biological classification is emerging. In this article, we introduce the mechanisms of brain invasion in atypical meningioma and review the genetic factors involved along with epigenetic regulation. First, it is important to understand the three major steps for brain invasion of meningeal cells: 1) degradation of extracellular matrix by proteases, 2) promotion of tumor cell migration to resident cells by adhesion molecules, and 3) neovascularization and supporting cells by growth factors. Second, the genomic landscape of meningiomas should be analyzed by major categories, such as germline mutations in NF2 and somatic mutations in non-NF2 genes (TRAF7, KLF4, AKT1, SMO, and POLR2A). Finally, epigenetic alterations in meningiomas are being studied, with a focus on DNA methylation, histone modification, and RNA interference. Increasing knowledge of the molecular landscape of meningiomas has allowed the identification of prognostic and predictive markers that can guide therapeutic decision-making processes and the timing of follow-up.

Asymptomatic Intraosseous Meningioma of the Humerus: A Case Report and Review of the Literature

Meningiomas are the most common central nervous system tumor. They are typically benign neoplasms but may produce neurological symptoms due to mass effect. Meningiomas may also extend to extradural locations; however, these account for only a small percentage of all meningiomas. Most extradural meningiomas arise in intraosseous locations, usually within the cranial bones or vertebrae. However, this is a rare case of extradural extension of an asymptomatic intracranial meningioma to the proximal humerus in the absence of any musculoskeletal symptoms. To the best of our knowledge, this presentation of an extradural intraosseous meningioma has not previously been reported in the literature. We present a case of an incidental intraosseous meningioma in a 66-year-old man. This patient was initially being screened for metastasis of stage IA1 adenocarcinoma of the lung, and a positron emission tomography (PET) scan revealed a focus of activity in the proximal diaphysis of the right humerus suspicious for malignancy. The upper extremity magnetic resonance imaging (MRI) demonstrated an indeterminate lesion. Curettage of the humeral lesion revealed an intraosseous psammomatous meningioma without evidence of metastatic lung carcinoma. Our case report aims to illustrate the importance of considering alternative metastatic sources, such as intracranial meningioma, during the investigation of an indeterminate bony lesion. This is the first case to illustrate asymptomatic intraosseous meningioma in an appendicular skeletal location, highlighting the need for thorough source investigation.

A rare case of metastatic atypical meningioma that highlights the shortcomings of treatment options at present

We report a case of a locally invasive recurrent atypical meningioma in the temporal region with late onset of meningioma lung metastasis. The patient was diagnosed in early adolescence with an atypical meningioma believed to be radiotherapy induced following treatment of a benign pilocytic astrocytoma in the hypothalamus region at 6 years of age. Even though the patient underwent several surgical and radiotherapy treatments, the intracranial meningioma kept growing and was locally invasive. The patient received experimental treatment with bevacizumab, a vascular endothelial growth factor A (VEGF-A)-inhibitor, for 4 years from age 26. Treatment was withdrawn after proven tumor growth on routine control MRI. A DOTA-TOC PET-CT-scan was performed to evaluate the DOTA-TOC somatostatin receptor number for possible SSTR (somatostatin receptor targeted therapy). In the included scan plan multiple lung metastasis were detected and later verified. Genomic tumor sequencing was performed, but no targeted treatment options were found. Instead, the patient finally, as the last treatment option, underwent 4 series of SSTR-targeted therapy (Lutetium DOTA-TOC). Unfortunately, the intracranial tumor component significantly progressed during the final stages of the treatment and the patient died less than a year after treatment was withdrawn at age 32. This case story illustrates the shortcomings of atypical/anaplastic meningioma treatment strategies at present and highlights the possibility of extracranial metastasis.

De Novo Glioblastoma Masqueraded within a Hemispheric Dural Meningiomatosis: Rare Imaging Findings and Rationale for Two-Staged Resection

Introduction  Collision tumors present as histologically different juxtaposed neoplasms within the same anatomical region, independent of the adjacent cell population. De novo intracranial collision tumors involving metachronous primary brain neoplasms alongside dural meningiomatosis are not well documented in the literature.

Clinical Presentation  We present staged surgical management of a 72-year-old female with known left hemispheric stable dural-based convexity mass lesions over 10 years and new-onset expressive aphasia and headaches. MRI had revealed left supratentorial dural-based enhanced masses consistent with en plaque meningiomatosis. Embolization angiography showed an unusual tumor blush from an aberrant branch of anterior cerebral artery suggesting a deeper focal intra-axial nature; a stage 1 craniotomy for dural-based tumor resection was completed with diagnosis of a meningioma (WHO grade 1). Intraoperatively, a distinct intra-axial deep discrete lesion was verified stereotactically, concordant with the location of tumor blush. The patient made a complete neurological recovery from a transient postoperative supplemental motor area syndrome in a week. Subsequent postoperative follow-up showed worsening of right hemiparesis and MRI showed an increase in residual lesion size and perilesional edema, which prompted a stage 2 radical resection of a glioblastoma, WHO grade 4. She improved neurologically after surgery with steroids and physical therapy. At 15 months following adjuvant therapy, she remains neurologically intact throughout the postoperative course, with no recurrent tumor on MRI.

Conclusion  A de novo glioblastoma presented as a masquerading lesion within hemispheric convexity meningiomatosis in an elderly patient with no prior radiation/phakomatosis, inciting a non-causal juxtapositional coexistence. The authors highlight rare pathognomonic angiographic findings and the rationale for two-staged resections of these collision lesions that led to excellent clinicoradiological outcome.

Molecular neuropathology of brain-invasive meningiomas

Invasion of brain tissue by meningiomas has been identified as one key factor for meningioma recurrence. The identification of meningioma tumor tissue surrounded by brain tissue in neurosurgical samples has been touted as a criterion for atypical meningioma (CNS WHO grade 2), but is only rarely seen in the absence of other high-grade features, with brain-invasive otherwise benign (BIOB) meningiomas remaining controversial. While post-surgery irradiation therapy might be initiated in brain-invasive meningiomas to prevent recurrences, specific treatment approaches targeting key molecules involved in the invasive process are not established. Here we have compiled the current knowledge about mechanisms supporting brain tissue invasion by meningiomas and summarize preclinical models studying targeted therapies with potential inhibitory effects.

Surgical management of de novo metastatic meningioma of the spine: An underestimated issue for WHO grade II/III meningiomas

OBJECTIVES

Meningioma is a slow-growing neoplasm derived from meningothelial cells. Extradural metastasis of WHO grade II/III meningiomas is relatively rare, and spinal metastatic meningiomas (SMM) have only been described in individual case reports. The aim of the present study is to discuss the clinical features and treatments of SMM patients.

METHODS

Fourteen SMM patients who received surgery in our center between 2010 and 2020 were reviewed retrospectively. Possible prognostic factors affecting local progression-free survival (LPFS) and overall survival (OS) were analyzed by log-rank analysis.

RESULTS

Our series comprised nine men and five women, with a median age of 49 years. The interval from the primary treatment to SMM varied from 1 to 11 years. Lesions were mainly located in the lumbar-sacral region (7/14, 50.0%), followed by the thoracic spine (5/14, 35.7%) and cervical (2/14, 14.3%) spine. The median follow-up period was 42.7 months, during which six patients (42.9%) passed away. Local tumor progression was detected in four patients (28.6%). Log-rank analysis indicated that circumferential surgery was associated with good LPFS, whereas WHO grade III and visceral metastasis were factors adversely affecting OS.

CONCLUSIONS

SMM is a challenging clinical entity, usually occurring in the fourth to fifth decades of life. Circumferential surgery is associated with good LPFS. WHO grade III and visceral metastasis are factors adversely affecting OS of patients with SMM. Long-term follow-up is recommended for patients who have received surgical treatment for primary meningiomas (Simpson Grade III/IV), especially for WHO III lesions.

Low-grade intracranial meningioma with bilateral pulmonary metastases incidentally detected postpartum: a case report and review of the literature

Introduction

Meningiomas are the most commonly encountered intracranial tumors, usually showing indolent behavior. Extra-axial spreading and distant metastases are seldom detected in these tumors, and lung metastasis from a low-grade meningioma is a rare event.

Case presentation

This case report aimed to present the clinical, imaging, and pathological features of a 37-year-old Caucasian pregnant woman with bilateral lung metastases incidentally detected during preoperative workup ahead of surgery for a primary intracranial meningioma. The possible metastatic routes and risk factors of dissemination to the pulmonary circulation were discussed as well.

Conclusion

Metastasis must be considered in patients with intracranial meningiomas accompanied by venous sinus invasion and extension through the calvarium. Thorough paraclinical investigations are suggested in such cases.

[Meningiomas: A review of current knowledge]

Meningiomas are the most frequent among intracranial tumors, and represent more than 30% of primitive central nervous system neoplasms. Arising from the meninges, they are generally benign lesions and can be treated by either radio-clinical follow-up or surgical resection with excellent outcome. However, more than 20% of meningiomas harbor atypical or malignant features and represent challenges for both prognostic evaluation and therapeutic strategy. The discovery of the genetic and epigenetic landscapes of meningiomas enabled the identification of new prognostic markers and potential therapeutic targets for refractory meningiomas. This review summarizes current epidemiology, histological and molecular characteristics, diagnosis and treatments for meningiomas, and highlights the close relationship between the development of meningiomas and hormonal intake, as illustrated by recent recommendations of the "Agence Nationale de Securité du Medicament", the French national drug safety agency.

Rhabdoid Meningioma Metastases Cervical Lymph Nodes: A Rare Clinical Case Report and Treatment Outcome

Meningioma is the most common central nervous system tumor that usually behaves benignly and has a good prognosis after treatment with tumor gross resection and with or without adjuvant therapy. Malignancy in meningioma is very rare and extracranial metastasis to cervical lymph nodes is even rarer. We report a case of a 40-year-old woman diagnosed with metastatic rhabdoid meningioma. She had recurrent primary disease and metastasis to bilateral cervical lymph nodes. She previously had intracranial tumor twice resected. We also review relevant, previously published cases in the literature. I hope you find these suggestions helpful.

The Myth of Prometheus in metastatic meningioma to the liver: from craniotomy to hepatectomy

Metastases from intracranial meningiomas are rare, and among them, meningiomas with hepatic dissemination are extremely rare. Therefore, there are currently no guidelines for staging and treatment of metastatic disease in meningioma, a disease that is a challenge for both the clinician and the pathologist. Our literature review revealed 24 cases of liver metastases originating from intracranial meningiomas. We used them to analyze the pathological patterns of dissemination and to assess the different management strategies available, the most efficient and beneficial being surgery and chemotherapy, especially in the case of meningiomas with hepatic and∕or systemic dissemination.

Meningioma: A Review of Epidemiology, Pathology, Diagnosis, Treatment, and Future Directions

Meningiomas are the most common intracranial tumor, making up more than a third of all primary central nervous system (CNS) tumors. They are mostly benign tumors that can be observed or preferentially treated with gross total resection that provides good outcomes. Meningiomas with complicated histology or in compromising locations has proved to be a challenge in treating and predicting prognostic outcomes. Advances in genomics and molecular characteristics of meningiomas have uncovered potential use for more accurate grading and prediction of prognosis and recurrence. With the study and detection of genomic aberrancies, specific biologic targets are now being trialed for possible management of meningiomas that are not responsive to standard surgery and radiotherapy treatment. This review summarizes current epidemiology, etiology, molecular characteristics, diagnosis, treatments, and current treatment trials.

Intracranial Grade II Meningioma Oligometastatic to the Cervical Spine

For intracranial meningiomas that metastasize extracranially, an oligometastatic state exists that is intermediate between incurable, widely metastatic disease and non-metastatic curable disease. Similar to oligometastatic cancer, aggressive local treatment of meningioma oligometastases is warranted, as it may be curable. We present a patient with multiply recurrent intracranial meningiomas over 19 years, with a transformation from grade I to grade II histology, with oligometastatic disease to the C5 vertebral body. Three years following definitive spinal stereotactic radiosurgery, she remains without evidence of other metastatic diseases. Our case highlights the oncologic concept that metastatic meningioma need not be widely disseminated and provides the clinical rationale for aggressive local treatment of an oligometastatic meningioma.

Liver metastasis from a non-recurrent atypical cranial meningioma: a case report

Extracranial metastases from atypical meningioma are rare, and even more so in the liver. We report a case of a 68-years-old patient with atypical meningioma, treated with partial surgical resection in 2012, and gamma knife radiotherapy in 2014 in another hospital, exhibiting a liver metastasis 6 years after the initial surgical resection.

A Grade I Intracranial Meningioma with Metastasis to Multiple Vertebral Bodies: A Case Report and Literature Review

World Health Organization (WHO) grade I meningiomas are slow-growing and typically benign brain tumors that can often be easily removed by surgery and rarely become malignant. We report the case of a WHO grade I meningioma in a 67-year-old man with multiple extracranial metastases.

Liver Metastasis from Typical Meningioma

BACKGROUND

Extracranial metastases from atypical meningioma are not usually found; they are sometimes found in lung, bone or scalp, but atypical meningioma in the liver is extremely rare.

CASE DESCRIPTION

We report a case of a 55-year-old patient with atypical meningioma, treated with surgical resection in 2005, who accepted a second surgical resection in 2015 by the same surgeon, caused by a liver metastasis 4 years after the second surgical resection.

CONCLUSIONS

We have analyzed the cytological findings of a metastastic meningioma with particular focus on pathological and immunohistochemical assessment. These results could improve the knowledge of surgeons about meningioma types and guide them to solve clinical incidents.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Meningioma metastases: incidence and proposed screening paradigm

OBJECTIVE

Extracranial meningioma metastases are uncommon, occurring in less than 1% of patients diagnosed with meningioma. Due to the rarity of meningioma metastases, patients are not routinely screened for distant disease. In this series, we report their experience with meningioma metastases and results of screening for metastases in select patients with recurrent meningiomas.

METHODS

All patients undergoing resection or stereotactic radiosurgery for primary or recurrent meningioma from 2009 to 2017 at a single center were retrospectively reviewed to identify patients who were diagnosed with or underwent imaging to evaluate for systemic metastases. Imaging to evaluate for metastases was performed with CT scanning of the chest, abdomen, and pelvis or whole-body PET/CT using either FDG or 68Ga-DOTA-octreotate (DOTATATE) tracers in 28 patients. Indications for imaging were symptomatic lesions concerning for metastasis or asymptomatic screening in patients with greater than 2 recurrences being evaluated for additional treatment.

RESULTS

Of 1193 patients treated for meningioma, 922 (77.3%) patients had confirmed or presumed WHO grade I tumors, 236 (19.8%) had grade II tumors, and 35 (2.9%) had grade III tumors. Mean follow-up was 4.3 years. A total of 207 patients experienced recurrences (17.4%), with a mean of 1.8 recurrences. Imaging for metastases was performed in 28 patients; 1 metastasis was grade I (3.6%), 16 were grade II (57.1%), and 11 were grade III (39.3%). Five patients (17.9%) underwent imaging because of symptomatic lesions. Of the 28 patients screened, 27 patients had prior recurrent meningioma (96.4%), with a median of 3 recurrences. On imaging, 10 patients had extracranial lesions suspicious for metastasis (35.7%). At biopsy, 8 were meningioma metastases, 1 was a nonmeningioma malignancy, and 1 patient was lost to follow-up prior to biopsy. Biopsy-confirmed metastases occurred in the liver (5), lung (3), mediastinum (1), and bone (1). The observed incidence of metastases was 0.67% (n = 8). Incidence increased to 2% of WHO grade II and 8.6% of grade III meningiomas. Using the proposed indications for screening, the number needed to screen to identify one patient with biopsy-confirmed malignancy was 3.83.

CONCLUSIONS

Systemic imaging of patients with multiply recurrent meningioma or symptoms concerning for metastasis may identify extracranial metastases in a significant proportion of patients and can inform decision making for additional treatments.

Subcutaneous Metastasis of Atypical Meningioma: Case Report and Literature Review

BACKGROUND

Meningioma, a neoplasm of the meninges, is usually a benign localized tumor. Extraneural metastasis is an extremely rare complication of meningiomas, and only a few cases have been reported to date. The present study reports a case of scalp metastasis of an atypical meningioma and discusses the types of atypical meningiomas and their management options.

CASE DESCRIPTION

A 69-year-old man presented with scalp metastasis of an atypical meningioma. Six years after the right frontoparietal meningioma lesion was completely resected, an isolated subcutaneous metastasis developed at the right frontal region of the scalp, originating at the scar left by the first surgery. Postoperative histologic examination of the subcutaneous tumor revealed the features of an atypical meningioma.

CONCLUSIONS

This study highlights that resection of meningiomas is still associated with a risk of iatrogenic metastasis. Surgeons should carefully wash out the operative field and change surgical tools frequently to avoid the potential risk of metastasis.

Infiltration of Benign Meningioma into Sagittal Sinus and Subsequent Metastasis to Lung: Case Report and Literature Review

BACKGROUND

Meningioma is an intracranial tumor frequently encountered in the neurosurgical setting. Extracranial disease is a rare occurrence, with a reported incidence in 0.1% of cases. Metastasis is associated with previous craniotomy, venous sinus invasion, local recurrence, and World Health Organization (WHO) grade III tumor. Metastasis of a benign, grade I meningioma is extraordinarily rare.

CASE DESCRIPTION

We report a case of a 41-year-old with a WHO grade I intracranial meningioma that had invaded and occluded the superior sagittal sinus. Chest computed tomography (CT) scan revealed pulmonary nodules, which were biopsied and confirmed benign meningioma. The metastatic meningiomas were found before resection of the primary tumor, suggesting direct seeding through the venous system versus iatrogenic seeding. Thirteen years later, an additional lung mass was found incidentally on abdominal CT scan for workup of a sarcoidosis. Biopsy and subsequent resection confirmed benign meningioma. A retrospective review of earlier chest CT scans revealed a small lesion that corresponded to the larger lesion found 13 years later.

CONCLUSIONS

This a rare case of a WHO grade I meningioma involving the sagittal sinus with direct seeding of the pulmonary vascular bed leading to multiple meningioma metastases. The report highlights an increased risk of distant metastases for a benign meningioma with invasion of dural sinuses.

WHO Grade I Meningioma Metastasis to the Lung 26 Years after Initial Surgery: A Case Report and Literature Review

Metastases from meningioma grade I are especially rare. We describe a case of a 65-year-old male with meningioma WHO grade I with a history of local recurrence and distant metastasis to the lung 26 years after the initial surgery. The original tumor was localized at the occipital low convex and invaded into the venous sinus and posterior cranial fossa; it was resected. About 15 years later, the tumor recurred in the posterior cranial fossa and γ-knife radiosurgery was performed. About 4 years later, the recurred tumor was resected at our hospital. Another 7 years later, the tumor recurred in the same area and right middle cranial fossa. All tumors except that inside the venous sinus were excised. All specimens obtained were classified as meningioma WHO grade I. Preoperative examination of the third operation revealed a nodule in the lower lobe of the right lung. The nodule grew gradually. Four months after the third surgery, partial resection of the right lung was performed. Histology indicated meningioma WHO grade I. The two lesions in the cranium and lung lesions were subjected to fluorescence in situ hybridization of the NF2 gene, and the three specimens had similar findings, genetically confirming them to be metastases of the intracranial meningioma. A literature review of past cases of meningioma progression revealed that the mean duration to metastasis is 12.5, 6.8, 3.7 years for grades I, II, and III, respectively. The current case therefore has an extended time frame.

Biopsy proven metastatic meningioma: A case report and review of the literature

Meningiomas are the most common type of benign tumor found in the brain and are typically benign, slow-growing lesions. The current standard of care consists of surgical resection and subsequent postoperative radiotherapy to prevent local recurrence. Because of their indolent nature, meningiomas are rarely found to spread extracranially and develop distant metastases. We present the clinical, imaging, and pathologic features of a patient who had meningioma with multiple local recurrences, who was incidentally found to have metastatic disease in the lungs. In addition, we discuss details of this case in the context of the previously reported literature.

Multimodal Management of Metastatic Malignant Meningiomas: The Role of Radiosurgery in Long-Term Local Control

BACKGROUND

Metastatic meningiomas (MMs) are rare (0.1 of 100 cases). Their treatment requires a multimodal approach, with surgery, radiotherapy, chemotherapy, and radiosurgery, which allows a long-term local control (LC) and an extension of free survival. In this study, the authors performed a review of the literature and reported 2 cases of patients affected by extracranial MMs, with long-term follow-up.

CASE DESCRIPTION

Case 1: A 48-year-old woman was admitted for resection of an extra-axial falx lesion (meningioma G1). After 2 years, the lesion got a local recurrence, resected with a histologic diagnosis of meningioma G3. During the next 9 years, the patient underwent 5 Gamma Knife radiosurgery (GKRS) procedures for local recurrence. At 56 years, she was readmitted for a surgical local recurrence (histologic definition: anaplastic meningioma G3). At the age of 62, the patient underwent a right lobectomy for a lung mass (histologic diagnosis: anaplastic meningioma G3). After that, multiple lesions at soma L5 and adrenal gland were discovered and then monitored. Case 2: A 48-year-old woman was operated for a lesion involving torcular herophili (meningioma G2). After 3 years, a local recurrence requires GKRS combined with tamoxifen. In the next 7 years, she underwent 5 GKRS procedures for local recurrence. The patient also underwent chemotherapy with octreotide. At the age of 61, she discovered multiple lesions in both lungs, liver, and kidney. A hepatic biopsy showed anaplastic meningioma G3. Also this patient does not suffer from any neurologic or clinical deficits.

CONCLUSIONS

LC in malignant meningioma is achievable through a multimodal approach; GKRS makes possible LC, but a novel aspect of these lesions is opened to discussion: the metastases. These reports show that multimodal treatment for MMs is an effective approach with good LC and improvement of overall survival. However, a long survival may allow systemic diffusion of the disease, in particular, when sagittal sinus is involved.

The Sovereignty of Primary Cranial Tumors-Meningiomas: Vetting the Cardinal Epidemiological Features

Introduction:

Cranial meningiomas considered one of most frequently encountered primary intracranial tumors in our daily neurosurgical practice, represent about 36% of brain neoplasms.

Aim:

In this cohort analysis, we investigated epidemiological features of brain meningiomas diagnosed at a single institution. Special highlighting has been dedicated to demographic features, foretelling radiological signs, and concomitant factors predictive of tumor atypia.

Material and Methods:

This retrospective analysis was conducted by revising all medical registries of patients aged ≥18 years, with a diagnosis of brain meningioma treated at King Hussein Medical Center, patients were retrieved from the electronic hospital database during a 12-year period (2004 to 2015). Preoperative radiology reports were examined to confirm tumor site and size based on largest measured dimension. Level of resection was based on surgical operative reports and post-operative radiological imaging.

Results:

A total of 665-patients operated for intracranial meningiomas were analyzed out of total 2047-patients operated for intracranial neoplasm during the same period. Demographic analysis showed; female to male ratio 2.4:1. Mean age 49.6-years. Average follow-up of 8.7 years. Tumor locations were classified as parasagittal (39.55%), convexity (27.52%), tentorial/ falx (6.17%), intraventricular (2.04%). Mean tumor size was 3,86 cm and tumor size was >4.5cm in (28. 07%) of cases. In this study we achieved gross total resection in (73.1%) of cases, subtotal resection in (22.6%). The majority of patients evolved favorably with respect to their neurological examination post-operatively, though a neurological deficit persisted in 64-cases and 16-cases developed a new neurological deficit. Ninety five cases developed recurrence during the observation period. Surgical mortality was reported in 11-cases in the immediate post-operative period and in 42-cases further cases during the observation period related to other causes.

Conclusion:

Neurosurgery faces a large number of intracranial meningioma patients in daily practice. Because of its “benign” nature; the variability in management strategy, Neurosurgery is more and more challenged with the concern of intracranial meningioma treatment in the daily practice. Because of its “benign” nature; the variability in management strategy, research regarding the meningioma etiology and epidemiology has lagged behind that for more malignant intracranial neoplasms. These risk factors piloted a revitalization in the study of meningiomas.

Whole-Body Staging of Metastatic Atypical Meningioma Using 68Ga-DOTATATE PET/CT

A 43-year-old woman with suspected recurrence of atypical meningioma World Health Organization grade II presented extensive intracranial lesions with high Ga-DOTATATE uptake. Moreover, numerous Ga-DOTATATE-positive bone, lung, and liver lesions were seen. For final diagnosis, biopsies taken from a lung lesion revealed distant metastases of the atypical meningioma. This case underlines the high diagnostic power of Ga-DOTATATE PET/CT for the staging of meningioma even beyond cerebral or spinal lesions; in case of distant lesions in patients with known meningioma, differential diagnosis should also contain metastases despite their rare occurrence. Moreover, this case emphasizes radioligand therapy especially in metastatic meningioma.

Primary Pulmonary Meningioma With Rhabdoid Features

Only 1% to 2% of meningiomas have primary extrameningeal location, which is mostly head and neck region. Primary pulmonary meningiomas (PPMs) are even more uncommon with up to 50 cases reported in the literature. Only 5 cases of PPM with confirmed or possible malignancy have been previously described. Three-grade classification of meningiomas with the accordingly growing risk of aggressive behavior of the tumor has been proposed by the World Health Organization. As it is based on correlations between morphological and clinical features of intracranial meningiomas, the analogous prediction of ectopic tumors prognosis remains questionable due to scarce number of cases. In this article, we present a rare case of PPM with rhabdoid features (World Health Organization grade III), which lacked other signs of malignancy. The patient is doing well for 2 years after the thoracoscopic wedge resection without evidence of the disease recurrence.

Mebendazole and radiation in combination increase survival through anticancer mechanisms in an intracranial rodent model of malignant meningioma

PURPOSE

Meningiomas are a frequent tumor of the central nervous system. Although mostly benign, approximately 5% present as atypical or malignant tumors. Treatments for atypical meningiomas include gross total resection and radiotherapy, but about 33% of patients have recurrent tumors, sometimes as a higher grade. Recently, the brain penetrant anthelmintic drug, mebendazole, has shown promise as an anticancer agent in rodent models of glioblastoma and medulloblastoma.

METHODS

The half maximal inhibitory concentration (IC₅₀) effect on colony formation, cell proliferation, and caspase-3/7 markers of apoptosis of mebendazole with and without radiation was measured in vitro. Mice intracranially implanted with KT21MG1 human meningioma were administered mebendazole alone or in combination with radiation. Survival benefit was evaluated, while tumors were investigated by immunohistochemical staining for apoptosis, cell proliferation, and vascular density.

RESULTS

In vitro experiments on meningioma cell lines showed the IC₅₀ for mebendazole in the range of 0.26-0.42 µM. Mebendazole alone induced cytotoxicity, however the combination had a greater reduction in colony formation and resulted in higher levels of cleaved caspase-3. The in vivo study showed both, mebendazole alone and the combination, to have a survival benefit with an increase in apoptosis, and decreases in tumor cell and vascular proliferation.

CONCLUSION

These preclinical findings indicate that mebendazole alone or in combination with radiation can be considered for the treatment of malignant meningioma. The mechanism of action for this combination may include an increase in apoptosis, a reduction in proliferation and angiogenesis, or a combination of these effects.

Malignant Transformation and Spine Metastasis of an Intracranial Grade I Meningioma: In Situ Immunofluorescence Analysis of Cancer Stem Cells Case Report and Literature Review

BACKGROUND

Malignant meningiomas are rare neoplasms of the central nervous system that occur de novo or rarely as a result of transformation. They have a higher rate of recurrence and metastasis accompanied by a significantly shorter survivorship compared with benign variants. Meningioma cancer stem cells (CSCs) have been previously shown to be associated with resistance and aggressiveness. However, the role they play in meningioma progression is still being investigated.

CASE DESCRIPTION

We report a 29-year-old man who underwent a resection of a grade I meningioma in 2011. The patient had multiple local recurrences of the tumor that showed an aggressive change in behavior and transformation to grade III meningioma, and developed extracranial metastasis to the cervical spine. He underwent multiple operations and received radiotherapy. Analysis of the tissues indicated the presence of CSC markers before metastasis, and showed increased expressions of associated markers in the metastasized tissue. In addition, similar to the patient's profile, the pharmacological testing of a primary cell line retrieved from the metastasized tissues showed a high level of drug tolerance and a diminished ability to initiate apoptosis.

CONCLUSIONS

Malignant progression of grade I meningioma can occur, and its eventuality may be anticipated by detecting CSCs. We performed a comprehensive literature review of relevant cases and discussed the clinical, diagnostic, and management characteristics of the reported cases.

A rare subtype of meningioma: Case series of anaplastic meningioma and review of the literature

RATIONALE

Anaplastic meningioma, a rare subtype of meningioma, has malignant morphological characteristics and a World Health Organization (WHO) grade of III.

PATIENT CONCERNS

In this report, we present findings from 6 cases of anaplastic meningioma.

DIAGNOSES

Pathological examination of the tumors, including hematoxylin and eosin staining and immunohistochemical staining, was performed. Of the six cases of anaplastic meningioma, two were recurrent tumors from original seminoma with a WHO grade of I. Histologically, three cases had carcinoma-like morphology, one case had sarcoma-like morphology, and two had two kinds of tissue structures: carcinoma-like tumor cell nests and areas with spindle tumor cells. Necrosis was detected in most cases (5/6). Ki67 index was high and varied from 20% to 70%.

INTERVENTIONS

All the patients received surgery. 3 patients received adjuvant radiotherapy. 1 patient received chemotherapy.

OUTCOMES

4 patients had no recurrence at follow-up of 19, 30, 46 and 54 months after the last surgery. 1 patient had recurrence 3 months after the last surgery. 1 patient died 12 days after the last surgery.

LESSONS

This malignant subtype can be secondary to a WHO grade I meningioma after a long quiescent period. Necrosis was common in the tumor tissues, and Ki67 index was usually high. For patients with a history of meningioma, including benign cases, regular physical examination is important for early detection of tumor recurrence and malignant transformation.