Diagnosis Of Meningioma Research Articles

ДИАГНОСТИКА И ТЕРАПИЯ МЕНИНГИОМЫ ОБЛАСТИ ТУРЕЦКОГО СЕДЛА

Currently, the number of oncological diseases among the population is growing significantly, accordingly, the practical significance of scientific works on the topic of oncology increases. It is a well-known fact that in the early stages of oncological diseases, most tumors respond much better to treatment, and the prognosis for the patient's life becomes many times more favorable. Based on this, it is necessary to consider a clinical case and analyze in our scientific articles tumors that often lead to patient disability and, in fact, are quite difficult to respond to various types of therapy. The issue of treating such neoplasms is one of the leading tasks of modern medicine. It is worth noting that among neoplasms, brain tumors occupy a fairly impressive position, and 10% of them are tumors of the arachnoid space of the meninges - meningiomas of the sella turcica. [1] The main problem associated with the diagnosis and treatment of meningiomas is their fairly deep localization and, most often, late detection. This is due to the symptoms characteristic of this tumor. It is worth noting the age features of the most frequent detection of meningiomas and tracking the correlation of this indicator with possible patient complaints, which will allow detecting a neoplasm at the earliest stage and significantly improving the prognosis of treatment and further rehabilitation of the patient. In this scientific work, a clinical case of meningioma in a 57-year-old patient was considered, the treatment she received was analyzed and a diagnostic technique for this pathology was proposed.

A Single Hepatic Metastasis of Cranial Meningioma on [18F]FDG PET/CT 16 Years After Initial Surgery.

Hepatic metastases of cranial meningiomas are rare, particularly when they present as a delayed, solitary metastasis, which poses a challenge for imaging-based diagnosis. [18F]FDG PET/CT facilitates diagnosis and posttreatment restaging, whereas somatostatin receptor-targeted PET demonstrates high sensitivity and specificity in the diagnosis of meningiomas and may potentially evaluate the viability of theranostics approaches, particularly for treatment-resistant meningiomas.

Artificial intelligence-driven radiological biomarkers: A narrative review of artificial intelligence in meningioma diagnosis

Artificial intelligence-driven radiological biomarkers: A narrative review of artificial intelligence in meningioma diagnosis

Quantitative tissue analysis reveals AK2, COL1A1, and PLG protein signatures: targeted therapeutics for meningioma.

Meningioma is the most prevalent primary intracranial brain tumor and accounts for one-third of all CNS tumors. Meningioma is known to be the most common yet life-threatening brain tumor with a higher recurrence rate. Globally, there is an increase in the healthcare burden due to meningioma and hence in its research. The present clinical approach includes surgical resection, chemotherapy, and radiation therapies to which the malignancy does not seem to respond efficiently. Targeted therapies and molecular markers provide elite patient treatment and care for individuals suffering from meningiomas as compared to conventional measures. Although there is proteomic data on meningioma the knowledge of potential biomarkers differentiating the grades is scarce. To identify the best set of biomarkers, validation of reported markers in large and independent sample cohorts in the future is necessary. A total of 12 samples, 3 each of control (which made pool 1) meningioma grade I (which made 2 sets: pool 2 and pool 3), and meningioma grade II (which made pool 4) were taken for LC-MS/MS. After this, the expression of three proteins was checked by immunocytochemistry, flow cytometry, and western blotting. Protein expression was analyzed using various techniques like mass spectrometry, immunocytochemistry, flow cytometry, and western blotting. Mass spectrometry is the most commonly used standard and reliable technique for identifying and quantifying protein expression. We got three highly upregulated proteins namely AK2, COL1A1, and PLG using this technique. The biomarker potential of these proteins was further checked by ICC, western blotting, and flow cytometry. Three important proteins were found to be upregulated namely, AK2 (Adenylate kinase 2), COL1A1 (collagen 1A1), and PLG (plasminogen). The order of increased protein expression was control < MG grade I < MG grade II according to mass spectrometry and western blotting. In immunocytochemistry, we found that COL1A1 expression increases significantly with grades in comparison to control. Similarly, AK2 and PLG also showed little increase but not as much as COL1A1. In flow cytometry, PLG showed higher upregulation in grades than control. While AK2 and COL1A1 showed little increase in expression in grades than control. All techniques, especially mass spectrometry and western blotting, presented higher expression of these proteins in grades as compared to control. In the quest to find a suitable therapeutic marker, this study incorporates quantitative labeling and detection followed by flow cytometry, immunocytochemistry, and western blotting for early diagnosis and treatment of meningioma. The article further explores the efficacy of some proteins namely AK2, COL1A1, and PLG to be the targeted molecules.

A two-site combined prediction model based on HOXA9 DNA methylation for early screening of risks of meningioma progression

To establish a recurrence risk prediction model for meningioma based on HOXA9 DNA methylation. Meningioma-related datasets were downloaded from GEO database for screening homeobox genes (HOXs) with prognostic values using differential methylation and ROC curve analysis and Cox regression analysis. The differentially methylated CpG sites with high predictive efficacy were selected to establish the risk prediction model using Lasso-Cox regression analysis, based on which the patients were divided into high- and low-risk groups by the cutoff value. The methylation levels of CpG sites were verified at the cell and tissue levels using methylation-specific PCR (MS-PCR). Clinical meningioma tissue samples were used to validate the predictive efficacy of the model. HOXA9 methylation level was significantly up-regulated in meningiomas (P< 0.001) and showed a high diagnostic efficiency (AUC=0.884) as an independent risk factor for overall survival (P< 0.01) positively correlated with the degree of malignancy and poor prognosis of meningioma (P< 0.05). Risk stratification by HOXA9 methylation was more accurate than WHO grading for predicting recurrence and patient survival time. The AUCs of the sites cg03217995 and cg21001184 were both above 0.8 for meningioma diagnosis and above 0.6 for predicting recurrence. The patients' clinical characteristics differed significantly between the high- and low-risk groups (P< 0.001), and the prediction score of the model was an independent prognostic factor for meningioma (P< 0.05). MSPCR results showed that the methylation levels of the two sites increased significantly in meningioma cells. In clinical samples, the combined model showed a high prediction efficiency (AUC=0.857), and the predicted risk of progression was highly consistent with the patients' actual condition. High HOXA9 methylation level is a predictor for poor prognosis of meningiomas, and the combined prediction model based on its CpG sites provides a new approach to early screening of meningioma patients at risk of progression.

NCMP-17. SPHENOID WING DIFFUSE LARGE B-CELL LYMPHOMA MIMICKING A MENINGIOMA: A RARE DIFFERENTIAL DIAGNOSIS

Abstract BACKGROUND Meningioma is the most frequent dural lesion and in most cases have a benign course and surgery usually is curative. Nevertheless, there are several dural lesions, neoplastic and non-neoplastic that may mimic meningiomas. Radiological features could help to perform this differentiation. Primary dural lymphoma (PDL) is a rare entity in which adjuvant therapy is required for proper therapeutic approach. CASE PRESENTATION A 67-year-old female patient presented with a clinical complaint of left exophthalmos and headache. During investigation, it was noticed the presence of a hyperintense left sphenoid wing lesion with orbital invasion. The diagnosis of meningioma was initially considered and she underwent neurosurgical approach aiming maximal extension. However, histopathological investigation disclosure that was a primary dural lymphoma (diffuse large B type) and she was referred to adjuvant therapy with a proper control of the disease. CONCLUSIONS Dural lesions could have neoplastic and non-neoplastic origin. Although meningiomas have a high prevalence, it must be considered other pathologies during evaluation and consideration of the differential diagnosis. This help to improve therapeutic management of the patients.

EPID-09. THE NATURAL HISTORY AND MOLECULAR ARCHITECTURE OF INCIDENTAL MENINGIOMAS

Abstract The prevalence of asymptomatic, incidental meningiomas is increasing due to greater frequency of brain imaging. This retrospective cohort study of adult patients presenting at a single institution from 1996-2020 integrated clinical data, serial magnetic resonance imaging (MRI) volumetrics, DNA methylation profiling, and targeted gene expression profiling to define the natural history and molecular architecture of incidental meningiomas. Volumetrics were calculated from contrast-enhanced brain MRIs at time of diagnosis compared to serial surveillance MRIs (average 3 MRIs per patient pre-intervention, range: 1-12) DNA methylation groups and gene expression risk scores were defined for 123 samples that underwent resection. Time-to-event analyses were performed for progression-free survival (PFS), symptom-free survival (SFS), and treatment-free survival (TFS). The cohort included 238 meningiomas from 207 patients. Median age at diagnosis was 59 years and 81.5% of patients were female. Median clinical and imaging follow-up were 9.1 and 6.7 years, respectively, during which time 50.8% progressed. Median maximum diameter and volume at diagnosis were 2.20 cm and 4.25 cm3, respectively, and median pre-treatment volumetric growth rate was 19.2% per year. Median pre-treatment PFS and TFS were 3.10 and 1.27 years, respectively, and median SFS and post-treatment PFS were not reached. Cox proportional hazards regression identified maximum diameter at diagnosis as a significant predictor of worse pre-treatment PFS (multivariate HR 1.65 per 1 cm [95% CI 1.19–2.28], p=0.0027) and worse TFS (multivariate HR 1.44 per 1 cm [95% CI 1.17–1.76], p&amp;lt;0.001). Skull base tumors had with worse SFS (multivariate HR 2.48 [95% CI 1.02–6.00], p=0.045). Molecular and histological features among incidental meningiomas that ultimately underwent resection (n=176, 74.0%) were reassuring (89.2% WHO grade 1, 10.2% WHO grade 2). These findings suggest maximum diameter at diagnosis of incidental meningiomas is significantly associated with earlier progression and eventual treatment, and skull base tumors have earlier symptom development.

TMET-38. BIOCHEMICAL CHARACTERIZATION OF PSAMMOMATOUS MENINGIOMA USING MAGNETIC RESONANCE SPECTROSCOPY

Abstract Psammomatous meningioma is a histologic subtype of meningioma and is presented as a highly calcified intracranial or spinal lesion. Although computed tomography (CT) and short/zero echo-time MRI techniques can detect calcification in tumors, a complete biochemical profile of psammomatous meningiomas is not known. Here, we compare the metabolomic profiles of common meningiomas (WHO grade-I and grade-II) and a psammomatous meningioma using ex vivo proton magnetic resonance spectroscopy (1H MRS). The tumor specimens were collected from meningioma patients undergoing surgery for the resection of the tumor mass. Tumor samples were extracted in 5% perchloric acid, centrifuged, supernatants were vacuum dried and reconstituted in D2O containing 1.0 mM sodium 2,2-dimethyl- 2-silapentane-5-sulfonate-d₆ (DSS-d6, internal standard). Previously, we have identified the following metabolites in grade-I and grade-II meningioma tumors: leucine, isoleucine, valine, lactate, alanine, acetate, glutamate, succinate, glutamine, aspartate, creatine, phosphocreatine, phosphocholine, glycerophosphocholine, myo-inositol, scyllo-inositol, taurine, hypotaurine, glycine, phosphoethanolamine, and glucose. In the current study, psammomatous meningioma also showed the presence of all the above metabolites; however, the levels of these metabolites were lower concentrations compared to the grade-I and grade-II meningiomas, except for lactate. In addition to the above-mentioned metabolites, psammomatous meningioma showed the presence of citrate which was not detected in other meningioma subtypes. Citrate is a major component of bone and the presence of citrate (~614 µM/g, tissue) in psammomatous meningioma could be due to the calcification occurring in these tumors. Surgical pathology report of resected tissue specimen showed clusters and small whorls of meningothelial cells with scattered calcifications, consistent with psammomatous meningioma (WHO grade-I; Ki-67 = 3%). In conclusion, detection of citrate by 1H MRS in meningiomas can be helpful in the differential diagnosis of psammomatous meningiomas.

PATH-15. DIGITAL PCR ANALYSIS FOR DETECTINGTERT PROMOTOR MUTATION IN MENINGIOMAS

Abstract The WHO Classification of Brain Tumors 5th edition requires the evaluation of TERT promoter mutations and CDKN2A/B homozygous deletions for the diagnosis of malignant meningiomas. Digital PCR (dPCR) is an emerging method for highly sensitive quantitative analysis. In this study, we performed TERT promoter mutation analysis using Pyrosequencing and dPCR in specimens with atypical and anaplastic meningiomas to investigate its utility and clinical significance. Adult patients diagnosed with atypical or anaplastic meningiomas after tumor resection between January 2009 and June 2023 were included. Genomic DNA was extracted from the excised specimens. TERT promoter mutations was analyzed by using the Pyrosequence and dPCR methods and compared with the clinical course. A total of 37 meningioma cases (13 males and 24 females) with 64 specimens were included. Atypical meningioma, grade II (WHO 2016) at diagnosis was 53 specimens (83%) and anaplastic meningioma, grade III (WHO 2016) was 11 specimens (17%). Of these, 7 (10%) were diagnosed with TERT promoter mutations by pyrosequencing, and one case with a low frequency (15%) of mutations by dPCR that tested negative by pyrosequencing had repeated recurrences in a short period of time. The dPCR method is highly sensitive in detecting low frequency TERT promoter mutations in tumor cell subpopulations and may contribute to the determination of treatment by predicting the malignant course of the disease. The results suggest that dPCR could contribute to therapeutic decision-making by detecting low-frequency TERT promoter mutations in tumor cell subpopulations.

RBIO-10. RADIATION FRACTION SIZE DIFFERENTIALLY AFFECTS MYELOID-DERIVED SUPPRESSOR CELL (MDSC) SUBSETS IN WHO GRADE 1 MENINGIOMA

Abstract Meningiomas are often cured after focal therapy with surgical resection and/or radiotherapy (RT); however, a small proportion still recur. RT dose can be used to modulate anti-tumor immune responses, potentially through regulating immunosuppressive MDSCs. Here, we investigate the effect of a single fraction of RT (2Gy vs. 15Gy) on frequency and activation status of MDSC subsets in patients with WHO grade 1 meningioma. We hypothesize that 2Gy will promote immunosuppressive MDSC activity more than 15Gy. Fresh tumor cells from patients with a presumed diagnosis of meningioma were digested into primary cell cultures and treated with a single fraction of 2 or 15 Gy or were sham irradiated using a XRAD 320 Biological Irradiator. Cells were incubated for 18hrs prior to flow cytometric analysis. MDSC populations were identified as Live/Dead-CD11b+CD33+HLA-DR-. MDSC subsets were then divided into M-MDSC (CD14+CD15-) or G-MDSC (CD15+CD14-). Five WHO grade 1 meningiomas were analyzed. The total frequency of MDSCs in tumors increased from 3% with sham RT to 4% after irradiation with 2Gy (p=0.03). This was driven by a 2-fold increase in frequency of total M-MDSCs, as G-MDSCs decreased by half after 2Gy (p=0.03). After irradiation with 15Gy, M-MDSC frequency was nearly half that of 2Gy. The frequency of TGF-β+MDSCs increased after 15 Gy (p=0.02). The frequency of IL-10+G-MDSCs increased in response to 2Gy (p =0.03) but decreased 4-fold after 15Gy. 18hrs after 2Gy, IFN-γ+M-MDSCs increased compared to sham (p=0.01). In this small cohort of grade 1 meningiomas, a 2Gy fraction of RT appeared to support expansion of the M-MDSC subset. RT at both fraction sizes increased immunosuppressive cytokine producing-MDSCs: M-MDSC-IL-10; G-MDSC-TGF-β. These findings indicate the need for further studies to understand the subset-specific impact of RT on MDSC, a key immune cell type in brain cancers.

082. Ectopic Meningothelial Meningioma of the Soft Palate – A Rare Case Report

Background: Ectopic meningiomas are rare neoplasms that occur entirely outside the intracranial and account for only 1–2% of all meningiomas. These tumors have been reported at various sites, however they are predominantly observed in the head and neck region. This study aims to document and analyze a rare case of ectopic meningothelial meningioma of the soft palate. Case: A 52-year-old woman who presented with a complaint of a lump in the roof of her mouth that had appeared five months prior. Examination of the local status through bimanual palpation revealed a mass in the soft palate extending to the oropharynx, displacing both the uvula and the anterior and posterior pillars. On imaging showed a solid, heterogeneous mass with central necrosis located in the right soft palate, extending into the oropharynx. The patient underwent a wide excision, which included ligation of the external carotid artery. Histopathology exams revealed an ectopic meningothelial meningioma. Conclusion: The diagnosis of ectopic meningioma may difficult due the occurrence in uncommon sites. The prognosis for tumours of the palate varies widely, depending on specific factors such as histology, tumor’s grade, margin status, cervical metastasis, and recurrence.

Delayed Surgical Management of a Giant Rhabdomyomatous Meningioma: A Case Report

Background and Importance: Rhomboid meningioma (RM) is one of the rare and aggressive types of meningioma, typically classified as a central nervous system grade III anaplastic meningioma by WHO. In this report, we present an unusual case of RM. Case Presentation: The patient was a 67-year-old man, living in Kermanshah City, Iran. He came to a neurosurgery clinic with a chief complaint of a huge and unusual mass on his skull. Following the brain computed tomography scan and magnetic resonance imaging, the diagnosis of meningioma was considered. The patient underwent surgical intervention for the excision of the mass. Immunohistochemical findings demonstrated the diagnosis of RM (WHO grade III). Conclusion: RM is a rare and aggressive subtype of meningiomas with a high growth rate and poor prognosis. Early diagnosis and treatment especially in invasive ones can prevent many unpleasant and critical complications; although tumor location has a pivotal role in determining treatment strategy.

Safety of 177Lu-DOTATATE administration in a patient with recurrent meningioma complicated by radiation necrosis: a case report

Radiation-associated meningiomas are characterized by high rates of recurrence. 177Lu-DOTATATE may represent a treatment option for these tumors, but safety of this agent for patients with a history of radiation necrosis is unknown. In this case report, we describe the preliminary safety of 177Lu-DOTATATE administration for a patient with prior history of radiation necrosis. The patient was diagnosed with central nervous system (CNS) germinoma at age 17, managed with chemoradiation. Twenty years later, a left-parietal extra-axial mass was identified within the prior radiation field, with diagnosis of atypical meningioma established on subtotal resection. He received additional radiation therapy (RT, 60 Gy, 30 fractions). Seventeen months later, tumor progression was treated with gamma knife radiosurgery (GKRS, 15 Gy, single fraction). Seven months after GKRS, seizures recurred, with imaging consistent with radiation necrosis. The patient was treated with bevacizumab (7.5 mg/kg, every 3 weeks, 4 doses). One year later, magnetic resonance imaging (MRI) brain revealed tumor progression within the treatment field. 68 Ga-DOTATATE positron emission tomography demonstrated that the meningioma was DOTATATE-avid with no evidence of metastasis. The patient was treated with 177Lu-DOTATATE (two infusions, two months apart), which was well tolerated with no significant toxicities and no recurrence of radiation necrosis. Two months after the second infusion, the patient experienced disease progression and was transitioned to bevacizumab. In this patient with three prior courses of intracranial radiation and subsequent radiation necrosis, 177Lu-DOTATATE was well-tolerated. 177Lu-DOTATATE administration may be feasible for patients with a history of radiation necrosis.

Grade-stratified meningioma risk among individuals who are Non-Hispanic black and interactions with male sex.

Meningioma risk factors include older age, female sex, and African-American race. Limited data explore how meningioma risk in African-Americans varies across the lifespan, interacts with sex, and differs by tumor grade. The Central Brain Tumor Registry of the United States (CBTRUS) is a population-based registry covering the entire U.S. population. Meningioma diagnoses from 2004-2019 were used to calculate incidence rate ratios (IRRs) for non-Hispanic Black individuals (NHB) compared to non-Hispanic white individuals (NHW) across 10-year age intervals, and stratified by sex and by WHO tumor grade in this retrospective study. 53,890 NHB individuals and 322,373 NHW individuals with an intracranial meningioma diagnosis were included in analyses. Beginning in young adulthood, the NHB-to-NHW IRR was elevated for both grade 1 and grade 2/3 tumors. The IRR peaked in the seventh decade of life regardless of grade, and was higher for grade 2/3 tumors (IRR = 1.57; 95% CI: 1.46-1.69) than grade 1 tumors (IRR = 1.27; 95% CI: 1.25-1.30) in this age group. The NHB-to-NHW IRR was elevated in females (IRR = 1.17; 95% CI: 1.16-1.18) and was further elevated in males (IRR = 1.28; 95% CI: 1.26-1.30), revealing synergistic interaction between NHB race/ethnicity and male sex (PInteraction=0.001). Relative to NHW individuals, NHB individuals are at elevated risk of meningioma from young adulthood through old age. NHB race/ethnicity conferred greater risk of meningioma among men than women, and greater risk of grade 2/3 tumors. Population-level differences in meningioma incidence and tumor behavior suggest potential disparities in the geographic, socioeconomic, and racial distribution of meningioma risk factors within the U.S.

Surgical treatment of meningiomas improves neurocognitive functioning and quality of life – a prospective single-center study

Background and purposeEarly diagnosis and the refinement of treatment of patients with intracranial meningiomas have brought quality of life (QoL) and neurocognitive functioning as outcome measures into focus. The aim of this study is a comprehensive assessment of neurocognitive function, quality of life and the presence of depression in meningioma patients before and after surgery.MethodsPatients with MRI diagnosis of intracranial meningioma and indication for surgery were prospectively included. A clinical neuropsychologist performed neurocognitive assessments within 3 months before and 12 months after surgery. The test battery included investigation of selective and divided attention, verbal and figural memory, executive functioning, and word fluency. Self-report questionnaires to assess depressive symptoms, QoL, and disease coping were administered. Raw values and t-values were compared pre-and postoperatively. Outcome was stratified by tumor- and peritumoral brain edema (PTBE) volumes, postoperative resolution of PTBE and WHO grade. The study included 18 predominantly female patients (83%) with a median age of 59 years and mostly CNS WHO grade 1 meningiomas (83%).ResultsThere was a significant postoperative improvement in the ability to selectively react under stress, in working memory and improved delayed reproduction of verbal and visual memory content. QoL improved regarding a reduction in physical problems, an improvement in energy, and social functioning. There was a trend towards worse preoperative scores in all tests, and greater postoperative improvement in patients with PTBE. Tumor volume had no effect on the measured outcome. The patients did not suffer from depressive symptoms before the surgery but improved postoperatively and most patients had an active, problem-oriented coping strategy.ConclusionResection of intracranial meningiomas leads to an improvement in multiple neurocognitive domains and QoL. There is a trend towards poorer preoperative neurocognitive functioning and greater postoperative improvement in patients with PTBE. Depression appears to play a minor role in the context of neurocognitive functioning and disease coping.

12363 A Unique Case Of hüRthle Cell Carcinoma of the Thyroid Gland and Meningioma

Abstract Disclosure: I. Elsayed: None. R. Khan: None. H. Dhaliwal: None. Introduction: MEN1 gene is a tumor suppressor gene on chromosome 11q13 that encodes the nuclear protein menin, which regulates cell growth and cycle. When menin protein is deficient, MEN1 develops. MEN1 mutation usually involves tumors within the parathyroid glands, pancreas, or pituitary. Case Description: A 66-year-old male with past medical history of hypertension, hyperlipidemia, and coronary artery disease presented with sudden onset dizziness, nausea and vomiting for 1 hour. He had similar symptoms on and off for several months, however on the day of presentation, these symptoms were much more acute and severe. Stroke work-up was done including CT and CTA head which revealed a 1.7cm enhancing lesion to R temporal lobe with surrounding edema with an incidental 3 x 3 cm heterogeneous mass in the large portion of the right thyroid gland. Steroids initiated. MRI brain imaging revealed findings consistent with meningioma with local mass effect and pronounced parenchymal edema. Patient underwent successful resection of the mass and pathology confirmed diagnosis of Meningioma, WHO Grade 1. Ear Nose Throat specialist was consulted for incidental thyroid mass. Ultrasound guided Fine needle aspiration biopsy was, Pathology report returned suspicious for follicular neoplasm, Hürthle cell-type. Patient initially underwent right substernal semi-thyroidectomy. Pathology confirmed diagnosis of Oncocytic (Hürthle cell) carcinoma, minimally invasive, 4.3 cm with a single focus of capsular invasion, negative for lymphovascular invasion Discussion: This case presents a 66-year-old male with a rare coexistence of two distinct tumors: a meningioma and a Hürthle cell carcinoma of the thyroid gland. While meningiomas and Hürthle cell carcinoma are not commonly associated with MEN1 syndrome, there have been reports of atypical cases with unusual tumor associations. MEN1 is usually characterized by abnormalities in at least two affected endocrine glands, but variations can involve other endocrine and non-endocrine tumors as well. 25% of thyroid disease can be seen in MEN 1 syndrome; typically papillary thyroid cancer. Only one case in literature found Hürthle cell carcinoma and meningioma in the setting of MEN-1 phenotype. A second case unique case was Hürthle cell carcinoma with metastases to the meninges. The discovery of both a meningioma and a Hürthle cell carcinoma in this patient emphasizes the importance of clinicians being vigilant for the possibility of multiple neoplasms. This case highlights that there may be a relation between role of MEN1 with atypical neoplasms not commonly seen. Presentation: 6/2/2024

Immunohistochemical Expression of Tenascin-C in Canine Meningiomas.

In humans, tenascin-C (TN-C) expression has been detected in more aggressive neoplasms of the central nervous system, such as gliomas and meningiomas. No study has analyzed the immune expression of TN-C in canine meningioma. The current study aimed to investigate the immunohistochemical distribution of TN-C in different grades of canine meningiomas. Twenty-one cases of canine meningioma (12 grade I, 6 grade II, and 3 grade III) were analyzed. All samples were examined by immunohistochemistry with the following antibodies: TN-C, epithelial membrane antigen (EMA), Ki-67, pan-cytokeratin (Pan CK), and vimentin. The histopathological diagnosis of meningioma was reinforced with the positive labeling of vimentin (moderate to strong) and EMA (mild to moderate) in neoplastic cells in most cases, independently of its grade or subtype. The immunoreactivity of TN-C was irregular: mild in grade I, moderate in grade II, and moderate to severe in grade III neoplasms. Usually, immune positivity was observed in the stroma and perivascular space in all subtypes. In addition, the concentric whorls of neoplastic cells were labeled positive in some psammomatous and transitional meningiomas. The reaction to TN-C was more significant in grade II and III tumors. The immunohistochemical findings of the current study suggest that TN-C can act as a stromal marker, mainly in grade II or III meningiomas.

Intracranial Rosai Dorfman disease Ó? A rare differential diagnosis of multiple meningiomas: case report

Intracranial Rosai Dorfman disease Ó? A rare differential diagnosis of multiple meningiomas: case report

MRI diagnosis of meningioma with marked skeletal hyperostosis and parenchymal infiltration in a 6‐year‐old standard poodle

AbstractA 6‐year‐old, neutered, male standard poodle was presented for evaluation of behaviour change. Neurological examination was consistent with a prosencephalic lesion. A magnetic resonance imaging study of the brain revealed a large non‐uniformly enhancing, extraparenchymal mass (9.2 × 8.7 × 5.0 cm) compressing the underlying brain parenchyma with heterogeneous T2‐weighted, T2‐fluid‐attenuated inversion recovery and T1‐weighted intensities. A meningioma with severe secondary hyperostosis and parenchymal invasion was identified on postmortem histological evaluation. To the authors’ knowledge, the presence of marked hyperostosis and calvarial infiltration to this degree, as well as the magnetic resonance imaging characteristics of these changes, have not previously been described in canine meningioma.

Intraoperative Incidental Internal Carotid Artery Injury in Extended Endoscopic Endonasal Approaches—Causes, Prevention, and Management: A Technical Note

AbstractIn spite of good anatomical awareness, the position of internal carotid artery (ICA) can be tricky in an intraoperative setup with disease causing very significant distortion of anatomy and shift of carotid artery and its branches. A 45-year-old gentleman presented with complaints of left hemicranial headache and painless progressive vision loss in both eyes (left more than right) for 8 months. A probable clinico-radiological diagnosis of meningioma was reached. Intraoperatively, bleeding occurred from left side ICA, control of which was achieved using a long gauze piece used as conventional nasal pack with crushed muscle beneath the gauze piece along with abdominal fat, which was further reinforced with Surgicel. The parasellar ICA is the most common segment injured. Dehiscent or bulging canal of ICA, presence of pseudoaneurysm, attachment of sphenoid septae to the canal, displacement by the lesion, nonenlarged sella because of small size of lesion or vertically oriented lesions, and vessel wall abnormalities increase the risk of injury. It is very essential to have a preoperative discussion involving the skull base surgeons (neurosurgeons and otorhinolaryngologists), neuroradiologists, and neuroanesthetists regarding the complications expected in the case. In case of ICA bleed, the target should be to achieve a temporary hemostasis. In small tears, cottonoids for pressure and bipolar for cauterization will help stop the bleeding, while in larger tears, giving moderate pressure using crushed muscle and cottonoids to achieve intra-operative hemostasis should be tried. After intraoperative hemostasis, the patient needs to be shifted to angiography suite for endovascular stent placement.