Intracranial extra-axial chondromas: clues to computed tomography and magnetic resonance imaging diagnosis.

AIM: We aimed to describe the computed tomography (CT) and magnetic resonance (MR) imaging findings of intracranial extra-axial chondroma. MATERIAL AND METHODS: We retrospectively evaluated the imaging findings of CT and MR examinations of six patients (three men and three women, aged 21-66 years) with histopathological diagnoses of intracranial extra-axial chondroma. RESULTS: Four tumors were located in the frontal region and two in the cavernous sinus. All the tumors showed low signals on diffusion-weighted images and high signals on apparent diffusion coefficient maps without restricted diffusion. There was no perifocal edema in all the tumors. Cavernous sinus chondromas were associated with bone erosion and anterior displacement of the internal carotid arteries, but without calcification. Calcification was present in all frontal chondromas. All the tumors revealed low signals on T1-weighted MR images. Frontal chondromas revealed mixed signals, but cavernous sinus chondromas were brightly hyperintense on T2-weighted MR images. No enhancement was detected in the two chondromas. An intense homogeneous enhancement was detected in a cavernous sinus chondroma. CONCLUSION: The imaging appearances of frontal extra-axial chondromas and cavernous sinus chondromas may have different imaging appearances. Although there is a wide range of imaging findings, the absence of restricted diffusion, perifocal edema, enhancement, and presence of low signals on T1-weighted MR images in a well-circumscribed calcified extra-axial mass should suggest an intracranial chondroma.

Vertebral Hemangiomas: Yucesoy-Yilmaz Classification System with Corresponding Therapeutic Options.

OBJECTIVE: Vertebral hemangiomas (VHs) are relatively common, symptomatic benign tumors of the spine with a reported estimated incidence up to 11%. They usually appear in the body of the vertebrae; however, they can extend into pedicles, laminae, and epidural space. They may cause pain, neurologic deficits. and fractures. METHODS: In this retrospective, single-center study, we reviewed our cases with VH and we propose the novel classification system that evaluates these lesions per their views on magnetic resonance imaging and clinical findings under 4 main categories. RESULTS: Our novel classification system proposes that grade I lesions occupy less than 50% of the vertebral body, whereas grade II lesions occupy more than 50% and grade III lesions occupy the whole corpus. Grade IV lesions show an epidural and pedicular extension. We propose that grade I lesions may not be worthwhile for follow-up, whereas asymptomatic grade II (a) lesions to be worthy for a biannual imaging and symptomatic thoracolumbar grade II (b) and thoracolumbar grade III lesions to be considered for percutaneous vertebroplasty. We imply that decompression, posterior spinal instrumentation, and open vertebroplasty may be performed for thoracolumbar grade IV lesions. We further consider cervical grade IIb, III, and grade IV lesions as operable because of the disadvantages of percutaneous vertebroplasty. CONCLUSIONS: We suggest that our novel classification system may be useful for the determination of diagnostic and therapeutic procedures in the management of VH. Further multicentric trials on larger series are warranted to validate this system and popularize its utility in larger populations.

Ectopic Pituitary Neuroendocrine Tumors/Adenomas Around the Sella Turcica

Functional or non-secretory ectopic pituitary neuroendocrine tumors (PitNET) can form around the sella turcica during the development of the adenohypophysis by differentiating and detaching from the pharyngeal roof. These tumors usually appear in the sphenoid sinus, clivus, cavernous sinus, infundibulum, and suprasellar cistern. Ectopic PitNETs typically display the characteristic magnetic resonance imaging findings of pituitary adenomas. However, preoperative diagnosis of PitNETs is usually challenging because of the variety of clinical and imaging presentations, locations, and sizes. Ectopic suprasellar PitNETs resemble mass lesions in the pituitary stalk. Ectopic cavernous sinus of PitNETs are typically microadenomas in the medial wall. Ectopic sphenoclival tumors are characterized by more aggressive tumor activity than the other ectopic PitNETs. Although ectopic PitNETs are exceedingly rare, they should be considered as a differential diagnosis for masses around the sella turcica. Treatment of the disease should be individualized and may include medical care, surgical resection, gamma-knife radiosurgery, and radiotherapy.

Super-enhancer hijacking drives ectopic expression of hedgehog pathway ligands in meningiomas.

Hedgehog signaling mediates embryologic development of the central nervous system and other tissues and is frequently hijacked by neoplasia to facilitate uncontrolled cellular proliferation. Meningiomas, the most common primary brain tumor, exhibit Hedgehog signaling activation in 6.5% of cases, triggered by recurrent mutations in pathway mediators such as SMO. In this study, we find 35.6% of meningiomas that lack previously known drivers acquired various types of somatic structural variations affecting chromosomes 2q35 and 7q36.3. These cases exhibit ectopic expression of Hedgehog ligands, IHH and SHH, respectively, resulting in Hedgehog signaling activation. Recurrent tandem duplications involving IHH permit de novo chromatin interactions between super-enhancers within DIRC3 and a locus containing IHH. Our work expands the landscape of meningioma molecular drivers and demonstrates enhancer hijacking of Hedgehog ligands as a route to activate this pathway  in neoplasia.

Silencing of the MEG3 gene promoted anti-cancer activity and drug sensitivity in glioma.

Aberrant expression of MEG3 has been shown in various cancers. The purpose of this study is to evaluate the effect of MEG3 on glioma cells and the use of potential chemotherapeutics in glioma by modulating MEG3 expression. Cell viability, migration and chemosensitivity were assayed. Cell death was evaluated in MEG3 overexpressing and MEG3 suppressed cells. MEG3 expression was compared in patient-derived glioma cells concerning IDH1 mutation and WHO grades. Silencing of MEG3 inhibited cell proliferation and reduced cell migration while overexpression of MEG3 promoted proliferation in glioma cells. MEG3 inhibition improved the chemosensitivity of glioma cells to 5-fluorouracil (5FU) but not to navitoclax. On the other hand, there is no significant effect of MEG3 expression on temozolamide (TMZ) treatment which is a standard chemotherapeutic agent in glioma. Suppression of the MEG3 gene in patient-derived oligodendroglioma cells also showed the same effect whereas glioblastoma cell proliferation and chemosensitivity were not affected by MEG3 inhibition. Further, as a possible cell death mechanism of action apoptosis was investigated. Although MEG3 is a widely known tumour suppressor gene and its loss is associated with several cancer types, here we reported that MEG3 inhibition can be used for improving the efficiency of known chemotherapeutic drug sensitivity. We propose that the level of MEG3 should be evaluated in the treatment of different glioma subtypes that are resistant to effective drugs to increase the potential effective drug applications.

Diffuse Leptomeningeal Glioneuronal Tumors: A Case Series of Five Patients with Parenchymal Forms and an Analysis of the Diagnostic Challenges, Treatment Options and Outcomes.

BACKGROUND: Diffuse leptomeningeal glioneuronal tumors (DL-GNT) are rare glioneuronal neoplasms with oligodendroglioma-like cells. These tumors can present as a dominant intracranial mass or as a solitary spinal cord mass without leptomeningeal involvement. In this study, we aimed to determine the magnetic resonance imaging and histopathological features, treatment modalities, and clinical outcomes of the parenchymal forms of DL-GNTs. METHODS: This is a retrospective three-center case series study of 5 patients with a confirmed parenchymal form of DLGTs, out of which 4 patients were adults. Brain and spinal cord MR imaging were performed in all patients at either 1.5 or 3T. The patients' age ranged from 5 years to 50 years with a mean age of 27.6 years at presentation. RESULTS: Four of the tumors were located in the frontal lobe, and one in the tectum. They were usually solid-cystic enhancing tumors as the other mixed neuronal-glial tumors. All of the tumors had an extension to the superficial surface of a cerebral hemisphere. One had systemic bone metastases. The clinical signs and symptoms of the parenchymal form varied based on the location of the mass, in contrast to the leptomeningeal form associated with hydrocephalus. In one case, the tumor's initial grade was defined as intermediate. The initial histopathology of the two cases was low-grade and no upgrade occurred in the follow-up period. In two cases, although the tumors were low grade initially, they progressed to an anaplastic form in the follow-up period. CONCLUSION: The parenchymal form of DL-GNTs is common in adults. Extension to the superficial surface of a cerebral hemisphere is a distinctive imaging feature. Systemic osseous metastasis may occur. Due to the presence of common histopathological features, including the biphasic composition of glial and neuronal cell elements and oligodendroglioma-like cells, a proposed classification approach might be more beneficial for the histopathological and imaging description, and management of the glioneuronal tumors with oligodendroglioma-like features.

Extensive widening of Virchow-Robin spaces in the frontal lobe: two case reports and systematic review of the literature.

AIM: To report our experience on giant tumefactive Virchow-Robin spaces (GTVRS) in the frontal lobe and perform a systematic review of previous reports on GTVRS. MATERIALS AND METHODS: This is a retrospective single-center study reporting the clinical manifestations, magnetic resonance (MR) imaging appearance, differential diagnosis, and management of two patients diagnosed with frontal lobe GTVRS at Bahcesehir University School of Medicine Goztepe Hospital in the past 5 years. A systematic literature search was performed in the PubMed and Google Scholar databases, with case selection criteria including Virchow-Robin spaces (VRS) size greater than 1.5 cm, frontal lobe localization, and the presence of MR imaging. The search strategy included only English language keywords. The systematic review was searched between database inception and May 6, 2022. RESULTS: A total of 18 cases were included in the study. Of the 15 cases with known sex, nine were female and six male. The median age was 29.8 with an age range of 4-57. Eleven of the 18 lesions were in the right frontal lobe. The lesions were multilocular in 15 cases and unilocular in three cases. All lesions had signal intensity as cerebrospinal fluid, showed no perifocal edema, and did not enhance. A hyperintensity was noted around the 14 lesions on the FLAIR sequence. Ten lesions showed cortical thinning adjacent to the lesion. No abnormality was detected on DWI, SWI, and MRS. Follow-up imaging was available in ten patients without any interval change. Unnecessary surgical interventions were noted in three cases. CONCLUSIONS: The results of reported cases and the literature review emphasize the role of MR imaging in the diagnosis of frontal lobe GTVRS. Beyond diagnostic consideration, GTVRS may have prognostic value and often indicate a "don't touch lesion" albeit requiring further consideration on a case-to-case basis. Familiarity with this entity improves diagnostic accuracy and, prevents accidental diagnosis of any neoplasm or other diseases.

Intracranial hemangiopericytoma after radiation treatment: first case in the literature.

BACKGROUND: Radiation exposure is a known risk factor for meningioma but there are no data regarding hemangiopericytoma and radiation exposure. CASE DESCRIPTION: We report a 29-year-old pineoblastoma patient diagnosed with a hemangiopericytoma at a different location, after a successful surgical excision and adjuvant radiotherapy for the original tumor 4-year prior. CONCLUSION: Hemangiopericytoma emergence can be seen after radiotherapy.

Malignant Progression of a Superior Cerebellar Tentorium Solitary Fibrous Tumor in the Pineal Region with Intracranial Metastases: A Case Report and a Literature Review.

BACKGROUND: Pineal region solitary fibrous tumors (SFT) incorporate a histologic spectrum of rarely metastasizing mesenchymal neoplasms that include tumors formerly classified as hemangiopericytoma. CASE REPORT: Here, we describe a rare case of SFT of the pineal region in a 25-year-old man with a literature review. After the first surgery, the tumor reappeared as a local low-grade recurrence, followed by metastasis to the right parietal lobe, and then hyperacute intraparenchymal hematoma at the metastatic site, and later presentation of widespread intracranial intra-axial and extra-axial metastases during the follow-up period. Systemic metastases were not detected. The histopathological evaluation of the resected tissues confirmed the malignant progression of the tumor. CONCLUSION: The diagnosis of SFT of the pineal region through clinical and imaging features can be considerably challenging. Large size, intratumoral cystic areas, and intense contrast enhancement are the main conventional imaging characteristics of the tumor. Surgery is the first preferential treatment. All recurrent or metastatic cases were grade II or grade III tumors. Adjuvant radiotherapy should be added to surgical treatment in high-grade tumors. Gamma knife radiosurgery is a treatment option for intracranial metastases.

A novel BH3 mimetic Bcl-2 inhibitor promotes autophagic cell death and reduces in vivo Glioblastoma tumor growth.

Anti-apoptotic members of the Bcl-2 family proteins play central roles in the regulation of cell death in glioblastoma (GBM), the most malignant type of brain tumor. Despite the advances in GBM treatment, there is still an urgent need for new therapeutic approaches. Here, we report a novel 4-thiazolidinone derivative BH3 mimetic, BAU-243 that binds to Bcl-2 with a high affinity. BAU-243 effectively reduced overall GBM cell proliferation including a subpopulation of cancer-initiating cells in contrast to the selective Bcl-2 inhibitor ABT-199. While ABT-199 successfully induces apoptosis in high BCL2-expressing neuroblastoma SHSY-5Y cells, BAU-243 triggered autophagic cell death rather than apoptosis in GBM A172 cells, indicated by the upregulation of BECN1, ATG5, and MAP1LC3B expression. Lc3b-II, a potent autophagy marker, was significantly upregulated following BAU-243 treatment. Moreover, BAU-243 significantly reduced tumor growth in vivo in orthotopic brain tumor models when compared to the vehicle group, and ABT-199 treated animals. To elucidate the molecular mechanisms of action of BAU-243, we performed computational modeling simulations that were consistent with in vitro results. Our results indicate that BAU-243 activates autophagic cell death by disrupting the Beclin 1:Bcl-2 complex and may serve as a potential small molecule for treating GBM.

IDH1 mutation activates mTOR signaling pathway, promotes cell proliferation and invasion in glioma cells.

BACKGROUND: Glioma is the most common type of brain tumors and isocitrate dehydrogenase (IDH1) gene is the most prominent molecular marker about the disease prognosis, response to therapy and patient survival. There are conflicting data about the effect of IDH1 mutation on glial cell proliferation, invasion and migration characteristics. The effect of IDH1 mutation on mTOR signaling pathway, which has key roles in tumorigenesis process, is limited and previous data is controversial. We aimed to explore the effect of wild type and mutant IDH1 overexpression on glioma cells and investigated the correlation with mTOR signaling pathway associated genes. METHODS AND RESULTS: U87-MG and A172 cells were transfected with different IDH1 mutant gene overexpressing (R132H, R132L, R132S, R132C) viral vectors. Cell proliferation, cell invasion and migration analysis as well as quantitative PCR analysis with the mutant glioma cell lines were performed. Forty-two patient derived glioma cells were obtained from patients with different glioma subtypes and cancer cells were enriched by culturing cells. Overexpression of both mutant and wild type IDH1 gene promoted the cell proliferation, but only IDH1 mutation increased cell invasion and migration. The expression of IDH1 mutation activated mTOR signaling via upregulation of WNTA, PRKAA2, GSK3B and MTOR genes as well as phosphorylated mTOR protein level. CONCLUSIONS: Our results highlighted IDH1 mutation upregulate mTOR signaling pathway and promote cell proliferation, invasion and migration.

Antiangiogenic Molecules Suppressed Meningioma-Induced Neovascularization: A Corneal Angiogenesis Study.

AIM: To investigate the angiogenic effects of bevacizumab and imatinib on different meningioma tissue grades. MATERIAL AND METHODS: In this study, in silico analysis of angiogenesis-related gene expression was carried out using previously reported datasets. Messenger ribonucleic acid expressions of VEGFA, VEGFB, PDGFRA, and PDGFRB genes were obtained from two different meningioma transcriptome datasets. The effect of antiangiogenic drugs, bevacizumab and imatinib, on meningiomainduced vascularization was assessed by using rat corneal angiogenesis assay (CAA). RESULTS: Bevacizumab and imatinib both significantly reduced meningioma-induced neovascularization in the CAA model. CONCLUSION: The angiogenic characteristics of meningiomas may be suppressed by using antiangiogenic drugs to prevent neovascularization, thus improving prognosis.

Magnetic Resonance Imaging of Unusual Neoplasms Related to Foramen of Luschka: A Review for Differential Diagnosis.

There are many types of neoplasms in or around the foramen of Luschka (FL), and definitive diagnosis in some cases requires knowledge of imaging findings. The uncommon and challenging neoplasms with FL involvement considered in this study are exophytic brainstem glioma, primary glioblastoma of the cerebellopontine angle (CPA), primary anaplastic ependymoma of the CPA, choroid plexus papilloma of the FL, solitary FL choroid plexus metastasis, extraskeletal myxoid chondrosarcoma of the jugular foramen, paraganglioma of the jugular foramen, exostosis of the jugular foramen, psammomatous meningioma in the lateral cerebellar medullary cistern, epidermoid tumor of the fourth ventricle, and a hypoglossal schwannoma. These neoplasms may have overlapping clinical and imaging features, but some have relatively distinct imaging features. Knowledge of the key clinical and magnetic resonance imaging features of these unusual lesions with FL involvement is important for radiologists to improve diagnostic ability and to assist the referring physician in the appropriate management of the patient.

Isolated Pituitary Metastasis of Renal Cell Carcinoma: A Case Report and Systematic Review of the Literature.

BACKGROUND: Isolated pituitary gland metastasis is an extremely rare event in renal cell carcinoma. We present a unique case of isolated pituitary metastasis of renal cell carcinoma and a systematic review of literature on it. CASE REPORT: In this case, an abdominal ultrasound in an asymptomatic 51-year-old female patient showed a mass in her left kidney. Radical nephrectomy was performed and the tumor was diagnosed as a stage 1 clear cell carcinoma. Throughout the 3 months of the follow-up period, the patient started complaining of visual disturbances and headaches. A pituitary mass was found on brain magnetic resonance imaging and was suspected to be a macroadenoma. Surgical resection of the tumor was performed and the final pathological diagnosis was made as a pituitary metastasis of the renal cell carcinoma. After surgery, radiotherapy with sunitinib, a receptor tyrosine inhibitor, was performed. CONCLUSION: The clinical symptoms are usually related to the mass effect of the tumor and anterior pituitary involvement. Most of the cases mimic pituitary macroadenoma on MRI. The most preferred treatment combination is surgery and radiotherapy. We recommend adding sunitinib to this combination. This illustrative case and those found in a systematic review of the literature highlight the importance of histopathologic diagnosis and appropriate management since isolated pituitary metastasis is challenging to preoperative diagnosis.

Cervical Venous Vascular Anatomy for Ventriculoatrial Shunt Applications: Anatomical Study and Surgical Approach Recommendation.

AIM: To develop an approach for atrial application of ventriculoatrial (VA) shunts after revealing the venous anatomy with facial and cervical anatomical dissections. MATERIAL AND METHODS: Five cephalic cadavers were used in the study. Facial and cervical regions of the cephalic cadavers were examined with layer by layer anatomical dissection. Venous angiography and ultrasonography were performed to obtain additional data on the cervical venous vascular anatomy. Subsequently, we developed an approach for atrial catheter applications. RESULTS: No anatomical variations were detected in the dissections. The common facial vein, which was formed by the facial vein and retromandibular vein, was observed to drain into the internal jugular vein. As a result of dissections and examinations, an incision approximately 2 cm below the mandible, extending from the projection of the submandibular notch to the trace of the angulus mandible, was considered adequate to expose the common facial vein for atrial catheter insertion. CONCLUSION: The approach described in our study is appropriate for the application of an atrial catheter for VA shunts. Revealing the venous anatomy with examinations contributes to the success of the operation.

Association of MTHFR, MTRR and RAD54L Gene Variations with Meningioma and Correlation with Tumor's Histopathological Characteristics on Turkish Cohort.

AIM: To elucidate the association of the MTHFR, MTRR, and RAD54L gene variations with meningioma in Turkish cohort. MATERIAL AND METHODS: DNAs were isolated from 87 retrospective meningioma samples. The MTHFR, MTRR, and RAD54L gene hotspot regions were amplified with specific primers via polymerase chain reaction (PCR), and next-generation sequencing (NGS) was performed. All the detected variations and single-nucleotide polymorphisms (SNPs) were listed and compared with healthy control frequencies in different genomic databases. The histopathological characteristics of meningiomas and genomic variations were compared. Pearson?s chi-squared test was used to detect the statistical differences of SNPs, and correlation analysis was conducted. RESULTS: rs1801131, rs1801133, and rs4846051 on MTHFR, rs1801394 on MTRR, and rs1048771 on RAD54L gene frequencies were found to be significantly altered in the overall cohort of 87 patients with meningioma. The frequency of rs18011031 is 0.09 in the meningioma cohort, which is significantly correlated with WHO tumor grades (p = 0.038). The frequency of rs18011033 is 0.29 in the meningioma cohort, which is significantly correlated with WHO tumor grades (p = 0.045). Furthermore, the frequency of rs4846051 is 0.18 in the meningioma cohort, which is significantly correlated with WHO tumor grades (p = 0.023) and also with low Ki67 proliferation index (p = 0.00455). The frequency of rs1801394 is 0.15 and significantly associated with high Ki67 proliferation index in the meningioma cohort (p = 0.0144). The frequency of rs1048771 is 0.09 in the meningioma cohort and is significantly associated with the non-necrotic histopathological form of the tumor (p = 0.05). CONCLUSION: We reported a significant association between the genetic alterations of folate metabolism (MTHFR, MTRR) and DNA repair mechanism (RAD54L) genes with the histopathological characteristics of meningioma. Five significant SNPs on these genes and four significant correlations of SNPs with histopathological characteristics were identified. This is a preliminary promising study conducted to establish the genetic marker analysis for meningioma diagnosis and prognosis for folate metabolism and DNA repair genes in Turkish cohort.

Magnetic resonance imaging criteria for prediction of isocitrate dehydrogenase (IDH) mutation status in patients with grade II-III astrocytoma and oligodendroglioma.

BACKGROUND: IDH mutation status is an important prognostic marker for glial tumors, which is detected immunohistochemically after surgery. Since this method is invasive, easy and noninvasive magnetic resonance imaging (MRI) methods have recently been used in predicting the IDH mutation status. However, there is currently no standard MRI technique to predict IDH mutation. We analyzed the value of conventional MRI to predict IDH mutation and its effect on survival among grade II-III astrocytoma and oligodendroglioma patients. MATERIAL AND METHODS: We included WHO grade II-III astrocytoma and oligodendroglioma patients who underwent surgery at Bahcesehir University Goztepe Medical Park Hospital. All patients were analyzed according to their immunohistochemical IDH mutation status. Preoperative conventional MRI studies with respect to their location, diffusion restriction, contrast enhancement, calcification and hemorrhage on susceptibility-weighted image (SWI) or T2*- weighted imaging (T2*WI), and T2 -FLAIR mismatch properties were retrospectively assessed by a neuroradiologist. The relation between MRI characteristics and IDH mutation was analyzed using a chi-square test. The sensitivity and specificity of radiological IDH mutation were determined by ROC analysis. The impact of IDH mutation on survival was also analyzed by Kaplan-Meier tests. RESULTS: IDH mutation was found to be positive in 82.5% of tumors histopathologically and 54.4% radiologically. The sensitivity and specificity were 63.8% and 90%, respectively (Area under the curve/AUC = 0.369, p = 0.08). IDH wild gliomas were predominantly diffusion-restricted tumors. IDH mutant tumors were less likely to have contrast enhancement and had lower grades compared to the IDH wild tumors. The median survival time could not be reached and the overall survival was not related to any tumor characteristics or IDH mutation. CONCLUSIONS: Conventional MRI predicts IDH-mutation status in Grade II-III astrocytoma and oligodendroglioma. Contrast-enhancement and restricted diffusion were strongly associated with grade III astrocytoma and oligodendroglioma, IDH-wild type. Location, T2-FLAIR mismatch, and SWI did not contribute to making a decision on the IDH mutation status. There was no significant difference between the survival times of patients and their IDH status.

Associations of meningioma molecular subgroup and tumor recurrence.

BACKGROUND: We and others have identified mutually exclusive molecular subgroups of meningiomas; however, the implications of this classification for clinical prognostication remain unclear. Integrated genomic and epigenomic analyses implicate unique oncogenic processes associated with each subgroup, suggesting the potential for divergent clinical courses. The aim of this study was to understand the associated clinical outcomes of each subgroup, as this could optimize treatment for patients. METHODS: We analyzed outcome data for 469 meningiomas of known molecular subgroup, including extent of resection, postoperative radiation, surveillance imaging, and time to recurrence, when applicable. Statistical relationships between outcome variables and subgroup were assessed. Features previously associated with recurrence were further investigated after stratification by subgroup. We used Kaplan-Meier analyses to compare progression-free survival, and identified factors significantly associated with recurrence using Cox proportional hazards modeling. RESULTS: Meningioma molecular subgroups exhibited divergent clinical courses at 2 years of follow-up, with several aggressive subgroups (NF2, PI3K, HH, tumor necrosis factor receptor-associated factor 7 [TRAF7]) recurring at an average rate of 22 times higher than others (KLF4, POLR2A, SMARCB1). PI3K-activated tumors recurred earlier than other subgroups but had intermediate long-term outcome. Among low-grade tumors, HH and TRAF7 meningiomas exhibited elevated recurrence compared with other subgroups. Recurrence of NF2 tumors was associated with male sex, high grade, and elevated Ki-67. Multivariate analysis identified molecular subgroup as an independent predictor of recurrence, along with grade and previous recurrence. CONCLUSION: We describe distinct clinical outcomes and recurrence rates associated with meningioma molecular subgroups. Our findings emphasize the importance of genomic characterization to guide postoperative management decisions for meningiomas.