World Health Organization Grades II and III meningiomas are rare in the cranial base and spine

The Endoscopic Lateral Transorbital Approach for the Removal of Select Sphenoid Wing and Middle Fossa Meningiomas. Surgical Technique and Short-Term Outcomes

BACKGROUND AND OBJECTIVE

The endoscopic lateral transorbital approach (eLTOA) is a relatively new approach to the skull base that has only recently been applied in vivo in the management of complex skull base pathology. Most meningiomas removed with this approach have been in the spheno-orbital location. We present a series of select purely sphenoid wing and middle fossa meningiomas removed through eLTOA. The objective here was to describe the selection criteria and results of eLTOA for a subset of sphenoid wing and middle fossa meningiomas.

METHODS

This is a retrospective study based on a prospectively maintained database of consecutive cases of eLTOA operated on at our institution by the lead author. The cohort's clinical and radiographic characteristics and outcome are presented.

RESULTS

Five patients underwent eLTOA to remove 3 sphenoid wing and 2 middle fossa meningiomas. The mean tumor volume was 11.9 cm 3 . Gross total resection was achieved in all cases. There were no intraoperative complications. Postoperatively, there was one case of subretinal hemorrhage, which was corrected by open vitrectomy repair, and one case of cerebrospinal fluid leak, which resolved with lumbar drainage. Three patients presented with visual impairment, 1 improved, 1 remained stable, and 1 worsened, but returned to stable after vitrectomy repair. All patients have been free of disease at a median follow-up of 8.9 months.

CONCLUSION

eLTOA provides a direct minimal access corridor to certain well-selected sphenoid wing and middle fossa meningiomas. eLTOA minimizes brain retraction and provides a high rate of gross total resection. Meningiomas appropriately selected based on size, type, and location of dural attachment, and the eLTOA is a safe, rapid, and highly effective procedure with acceptable morbidity.

Different clinical and cytogenetic features of primary skull base meningiomas and non-skull base meningiomas

PURPOSE

To investigate the different clinical and cytogenetic features of skull base meningiomas (SBMs) and non-SBMs (NSBMs).

METHODS

We conducted a retrospective study on a series of 316 patients with primary intracranial meningiomas. The t-test and the Chi-square test were used to analyze the differences between 194 SBMs and 122 NSBMs. The Cox analysis was used to determine prognostic factors for tumor recurrence.

RESULTS

Compared with NSBMs, on average, the age of patients with SBMs was about 2.88 years younger (p = 0.024); the duration of operation of SBMs was 2.73 h longer (p < 0.001); the duration of hospital stays of patients with SBMs was about 6.76 days longer (p < 0.001); the tumor volume was 7.69 cm³ smaller (p = 0.025); the intraoperative blood loss was 147.61ml more (p = 0.039); the total cost of SBMs was 1.39 times more (p < 0.001); the preoperative KPS, postoperative KPS, and follow-up KPS of patients with SBMs were all respectively lower (p < 0.001); Gross total resection was less achieved (p < 0.001). SBMs (average of 20.80 per sample) had a smaller total number of copy number variations (CNVs) than NSBMs (29.98 per sample) (p = 0.009). Extremely large CNVs (> 5 Mb) were more likely to present in NSBMs (p < 0.001). Cox analysis showed that subtotal resection (p = 0.002) and the total number of CNVs (p = 0.015) were independent risk factors for tumor recurrence.

CONCLUSIONS

The clinical and cytogenetic features of SBMs were different from NSBMs. Moreover, the degree of resection and the total number of whole-genome CNVs were independent prognostic factors for tumor recurrence.

Craniovertebral Junction Instability after Oncological Resection: A Narrative Review

The craniovertebral junction (CVJ) is a complex transition area between the skull and cervical spine. Pathologies such as chordoma, chondrosarcoma and aneurysmal bone cysts may be encountered in this anatomical area and may predispose individuals to joint instability. An adequate clinical and radiological assessment is mandatory to predict any postoperative instability and the need for fixation. There is no common consensus on the need for, timing and setting of craniovertebral fixation techniques after a craniovertebral oncological surgery. The aim of the present review is to summarize the anatomy, biomechanics and pathology of the craniovertebral junction and to describe the available surgical approaches to and considerations of joint instability after craniovertebral tumor resections. Although a one-size-fits-all approach cannot encompass the extremely challenging pathologies encountered in the CVJ area, including the possible mechanical instability that is a consequence of oncological resections, the optimal surgical strategy (anterior vs posterior vs posterolateral) tailored to the patient's needs can be assessed preoperatively in many instances. Preserving the intrinsic and extrinsic ligaments, principally the transverse ligament, and the bony structures, namely the C1 anterior arch and occipital condyle, ensures spinal stability in most of the cases. Conversely, in situations that require the removal of those structures, or in cases where they are disrupted by the tumor, a thorough clinical and radiological assessment is needed to timely detect any instability and to plan a surgical stabilization procedure. We hope that this review will help shed light on the current evidence and pave the way for future studies on this topic.

Association between preoperative hematologic markers and aggressive behavior in meningiomas

INTRODUCTION

Meningiomas have varying degrees of aggressive behavior. Some systemic hematologic makers are associated with malignancy, but their value in predicting aggressive meningioma behavior is not fully understood.

OBJECTIVE

To evaluate the association between preoperative markers such as neutrophil-lymphocyte ratio (NLR), neutrophil-monocyte ratio (NMR), monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), and prognostic nutritional index (PNI), and diagnostic and prognostic factors including WHO grade, proliferation index, presence of edema on preoperative MRI, and tumor recurrence.

METHODS

A retrospective review of patients treated between 2000 and 2019 with a preoperative complete blood count (CBC) differential lab draw before intracranial meningioma resection was conducted. All preoperative steroid dosages were converted to dexamethasone equivalents. Primary outcomes included presence/absence of perilesional edema, WHO grade, Ki-67/MIB-index, and recurrence. Univariate and multivariable regression analyses were conducted.

RESULTS

A total of 209 meningioma patients were included. Of these, 143 (68 %) were WHO grade I, 61 (29 %) grade II and 5 (2 %) were grade III. Recurrence was reported in 19 (9.1 %) tumors. No hematologic markers were associated with recurrence. In separate multivariable logistic analyses, no biomarkers were associated with perilesional edema or WHO grade. MLR was associated with higher MIB-index (p = 0.018, OR 6.57, 95 % CI 1.37-30.91).

CONCLUSION

Most hematologic markers were not associated with meningioma invasiveness, grade, proliferative index, or aggressiveness. Preoperative MLR was associated with high proliferation index in patients undergoing surgery for intracranial meningioma. Higher MLR could be a surrogate for meningioma proliferation and has potential to be used as an adjunct for risk-stratifying meningiomas.

Clinical Management of Supratentorial Non-Skull Base Meningiomas

Supratentorial non-skull base meningiomas are the most common primary central nervous system tumor subtype. An understanding of their pathophysiology, imaging characteristics, and clinical management options will prove of substantial value to the multi-disciplinary team which may be involved in their care. Extensive review of the broad literature on the topic is conducted. Narrowing the scope to meningiomas located in the supratentorial non-skull base anatomic location highlights nuances specific to this tumor subtype. Advances in our understanding of the natural history of the disease and how findings from both molecular pathology and neuroimaging have impacted our understanding are discussed. Clinical management and the rationale underlying specific approaches including observation, surgery, radiation, and investigational systemic therapies is covered in detail. Future directions for probable advances in the near and intermediate term are reviewed.

Symptom burden and surgical outcome in non-skull base meningiomas

Purpose

Non-skull base meningiomas (NSBM) are a distinct entity and frequently present with focal neurological deficits. This study was designed to analyze functional and oncological outcome following microsurgical tumor resection in patients with NSBM.

Patients and methods

An analysis of 300 patients that underwent NSBM resection between 2003 and 2013 was performed. Assessment measures for functional outcome were Karnofsky Performance Scale (KPS), Medical Research Council - Neurological Performance Scale (MRC-NPS), and improvement rates of focal deficits and seizures. The extent of resection; recurrence-free survival (RFS) and tumor-specific survival (TSS) were also determined.

Results

Impaired KPS and MRC-NPS were present in 73.3% and 45.7%, respectively. Focal neurological deficits were recorded in 123 patients (41.0%), with hemiparesis (21.7%) and aphasia (9.3%) the most prevalent form of impairment. Most meningiomas were localized at the convexity (64.0%), followed by falcine tumors (20.3%). Both KPI and MRC-NPS scores were significantly improved by surgical resection. Postoperative improvement rates of 96.6%, 89.3%, 72.3%, 57.9%, and 27.3% were observed for aphasia, epilepsy, hemiparesis, cranial nerve, and visual field deficits, respectively. Long-term improvement was achieved in 83.2%, 89.3%, 80.0%, 68.4% and 54.6% of patients, respectively. Gross total resection (GTR) over subtotal resection (STR) significantly improved preoperative seizures and visual field deficits and correlated with reduced risk of new postoperative hemiparesis. Poor Simpson grade was the only significant prognostic factor in multivariate analysis for long-term functional deficit, which occurred in 7.3%. Median RFS was 45.9 months (6.0 - 151.5 months), while median TSS was 53.7 months (3.1 - 153.2 months). Both WHO grade (p= 0.001) and Simpson classification (p= 0.014 and p= 0.031) were independent significant prognostic factors for decreased RFS and TSS by multivariate analysis, respectively. Furthermore, tumor diameter > 50 mm (p= 0.039) significantly correlated with decreased TSS in multivariate analysis.

Conclusion

Surgical resection significantly and stably improves neurological deficits in patients with NSBM.

Transcriptomic Profiling Revealed Lnc-GOLGA6A-1 as a Novel Prognostic Biomarker of Meningioma Recurrence

BACKGROUND

Meningioma is the most common primary central nervous system neoplasm, accounting for about a third of all brain tumors. Because their growth rates and prognosis cannot be accurately estimated, biomarkers that enable prediction of their biological behavior would be clinically beneficial.

OBJECTIVE

To identify coding and noncoding RNAs crucial in meningioma prognostication and pathogenesis.

METHODS

Total RNA was purified from formalin-fixed and paraffin-embedded tumor samples of 64 patients with meningioma with distinct clinical characteristics (16 recurrent, 30 nonrecurrent with follow-up of >5 years, and 18 with follow-up of <5 years without recurrence). Transcriptomic sequencing was performed using the HiSeq 2500 platform (Illumina), and biological and functional differences between meningiomas of different types were evaluated by analyzing differentially expression of messenger RNA (mRNA) and long noncoding RNA (IncRNA). The prognostic value of 11 differentially expressed RNAs was then validated in an independent cohort of 90 patients using reverse transcription quantitative (real-time) polymerase chain reaction.

RESULTS

In total, 69 mRNAs and 108 lncRNAs exhibited significant differential expression between recurrent and nonrecurrent meningiomas. Differential expression was also observed with respect to sex (12 mRNAs and 59 lncRNAs), World Health Organization grade (58 mRNAs and 98 lncRNAs), and tumor histogenesis (79 mRNAs and 76 lncRNAs). Lnc-GOLGA6A-1, ISLR2, and AMH showed high prognostic power for predicting meningioma recurrence, while lnc-GOLGA6A-1 was the most significant factor for recurrence risk estimation (1/hazard ratio = 1.31; P = .002).

CONCLUSION

Transcriptomic sequencing revealed specific gene expression signatures of various clinical subtypes of meningioma. Expression of the lnc-GOLGA61-1 transcript was found to be the most reliable predictor of meningioma recurrence.

The Long and Winding Road: An Overview of the Immunological Landscape of Intracranial Meningiomas

Simple Summary

The tumor microenvironment represents the essential basis for characterizing oncological cells and supporting their growth. Along with genomic sequencing, the study of the tumor microenvironment represents a big step forward in oncological research and in the customization of treatments. Compared to gliomas, for which research has discovered greater results, the correlation between the microenvironment and tumor phenotype, and consequent prognostic implications, are still incompletely understood for intracranial meningioma. Recently, studies about the immunogenetic landscape of meningiomas have been promoted, and it is now clear that understanding the multifactorial pathogenesis of meningioma and its correlation with other specific signs (i.e., PTBE) could lead to the development of new targeted therapies, and significantly affect meningioma patients’ prognosis.

Abstract

The role of immunotherapy is gaining ever-increasing interest in the neuro-oncological field, and this is also expanding to the management of intracranial meningioma. Meningiomas are still the most common primary adult tumor of the CNS, and even though surgery and/or radiotherapy still represent cornerstones of their treatment, recent findings strongly support the potential role of specific immune infiltrate cells, their features and genomics, for the application of personalized treatments and prognostic implications. According to the PRISMA guidelines, systematic research in the most updated platform was performed in order to provide a descriptive and complete overview about the characteristics, role and potential implications of immunology in meningioma tumors. Seventy articles were included and analyzed in the present paper. The meningioma microenvironment reveals complex immune tumor-immune cells interactions that may definitely influence tumor progression, as well as offering unexpected opportunities for treatment.

Clinical and pathological impact of an optimal assessment of brain invasion for grade 2 meningioma diagnosis: lessons from a series of 291 cases

Brain invasion has not been recognized as a standalone criterion for atypical meningioma by the WHO classification until 2016. Since the 2007 edition suggested that meningiomas harboring brain invasion could be classified as grade 2, brain invasion study was progressively strengthened in our center, based on a strong collaboration between neurosurgeons and neuropathologists regarding sample orientation and examination. Practice changes were considered homogeneous enough in 2011. The aim of the present study was to evaluate the impact of gross practice change on the clinical and pathological characteristics of intracranial meningiomas classified as grade 2.The characteristics of consecutive patients with a grade 2 meningioma surgically managed before (1998-2005, n = 125, group A) and after (2011-2014, n = 166, group B) practices changed were retrospectively reviewed.Sociodemographical and clinical parameters were comparable in groups A and B, and the median age was 62 years in both groups (p = 0.18). The 5-year recurrence rates (23.2% vs 29.5%, p = 0.23) were similar. In group A, brain invasion was present in 48/125 (38.4%) cases and was more frequent than in group B (14/166, 8.4%, p < 0.001). In group A, 33 (26.4%) meningiomas were classified as grade 2 solely based on brain invasion (group A_SBI), and 92 harbored other grade 2 criteria (group A_OCA). Group A_SBI meningiomas had a similar median progression-free survival compared to groups A_OCA (68 vs 80 months, p = 0.24) and to A_OCA and B pooled together (n = 258, 68 vs 90 months, p = 0.42).An accurate assessment of brain invasion is mandatory as brain invasion is a strong predictor of meningioma progression.

Regrowth factors of WHO grade I skull base meningiomas following incomplete resection

OBJECTIVE

The role of adjuvant radiation therapy following incomplete resection of WHO grade I skull base meningiomas (SBMs) is controversial, and little is known regarding the behavior of residual tumors. The authors investigated the factors that influence regrowth of residual WHO grade I SBMs following incomplete resection.

METHODS

From 2005 to 2019, a total of 710 patients underwent surgery for newly diagnosed WHO grade I SBMs. The data of 115 patients (16.2%) with incomplete resection and without any adjuvant radiotherapy were retrospectively assessed during a mean follow-up of 78 months (range 27-198 months). Pre-, intra-, and postoperative clinical and molecular factors were analyzed for relevance to regrowth-free survival (RFS).

RESULTS

Eighty patients were eligible for analysis, excluding those who were lost to follow-up (n = 10) or had adjuvant radiotherapy (n = 25). Regrowth occurred in 39 patients (48.7%), with a mean RFS of 50 months (range 3-191 months). Significant predictors of regrowth were Ki-67 proliferative index (PI) ≥ 4% (p = 0.017), Simpson resection grades IV and V (p = 0.005), and invasion of the cavernous sinus (p = 0.027) and Meckel's cave (p = 0.027). After Cox regression analysis, only Ki-67 PI ≥ 4% (hazard ratio [HR] 9.39, p = 0.003) and Simpson grades IV and V (HR 8.65, p = 0.001) showed significant deterioration of RFS. When stratified into 4 scoring groups, the mean RFSs were 110, 70, 38, and 9 months for scores 1 (Ki-67 PI < 4% and Simpson grade III), 2 (Ki-67 PI < 4% and Simpson grades IV and V), 3 (Ki-67 PI ≥ 4% and Simpson grade III), and 4 (Ki-67 PI ≥ 4% and Simpson grades IV and V), respectively. RFS was significantly longer for score 1 versus scores 2-4 (p < 0.01). Tumor consistency, histology, location, peritumoral edema, vascular encasement, and telomerase reverse transcriptase promoter mutation had no impact on regrowth.

CONCLUSIONS

Ki-67 PI and Simpson resection grade showed significant associations with RFS for WHO grade I SBMs following incomplete resection. Ki-67 PI and Simpson resection grade could be utilized to stratify the level of risk for regrowth.

Primary Intraosseous Osteolytic Meningioma with Aggressive Clinical Behaviour: Clinico-Pathologic Correlation and Proposed New Clinical Classification

(1) Introduction: Primary intraosseous osteolytic meningiomas (PIOM) are non-dural-based tumors predominantly presenting an osteolytic component with or without hyperostotic reactions. They are a subset of primary extradural meningiomas (PEM). In this study, we present a peculiar case with a systematic literature review and propose a new classification considering the limitations of previous classification systems. (2) Materials and Methods: Using a systematic search protocol in Google Scholar, PubMed, and Scopus databases, we extracted all case studies on PIOM published from inception to December 2020. A 46-year-old female patient form Dhaka, Bangladesh, was also described. The search protocol was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. (3) Results: Here, we present a 46-year-old female patient with PIOM who successfully underwent bifrontal craniotomy and gross total removal (GTR) of the tumor. At 6-month follow-up, no tumor recurrence was shown. Including our new case, 55 total cases from 47 articles were included in the analysis. PIOMs were in closer frequency among males (56.4%) and females (43.6%). The most common tumor location was the frontal and parietal calvarium, most commonly in the frontal bone (29.1%). Surgical resection was the predominant modality of treatment (87.3%); only 1.8% of patients were treated with radiotherapy, and 5.4% received a combination of surgery and radiotherapy. Gross total resection (GTR) was achieved in 80% of cases. Extracranial extension was reported in 41.8% of cases, dural invasion in 47.3%, and recurrence in 7.3%. Whole-body 68 Ga-DOTATOC PET/CT has also been reported as a useful tool both for differential diagnosis, radiotherapy contouring, and follow-up. Current treatments such as hydroxyurea and bevacizumab have variable success rates. We have also suggested a new classification which would provide a simple common ground for further research in this field. (4) Conclusions: Surgical resection, especially GTR, is the treatment of choice for PIOM, with a high GTR rate and low risk of complications and mortality. More research is needed on the differential diagnosis and specific treatment of PIOM.

Are there predilection sites for intracranial meningioma? A population-based atlas

Meningioma is the most common benign intracranial tumor and is believed to arise from arachnoid cap cells of arachnoid granulations. We sought to develop a population-based atlas from pre-treatment MRIs to explore the distribution of intracranial meningiomas and to explore risk factors for development of intracranial meningiomas in different locations. All adults (≥ 18 years old) diagnosed with intracranial meningiomas and referred to the department of neurosurgery from a defined catchment region between 2006 and 2015 were eligible for inclusion. Pre-treatment T1 contrast-enhanced MRI-weighted brain scans were used for semi-automated tumor segmentation to develop the meningioma atlas. Patient variables used in the statistical analyses included age, gender, tumor locations, WHO grade and tumor volume. A total of 602 patients with intracranial meningiomas were identified for the development of the brain tumor atlas from a wide and defined catchment region. The spatial distribution of meningioma within the brain is not uniform, and there were more tumors in the frontal region, especially parasagittally, along the anterior part of the falx, and on the skull base of the frontal and middle cranial fossa. More than 2/3 meningioma patients were females (p < 0.001) who also were more likely to have multiple meningiomas (p < 0.01), while men more often have supratentorial meningiomas (p < 0.01). Tumor location was not associated with age or WHO grade. The distribution of meningioma exhibits an anterior to posterior gradient in the brain. Distribution of meningiomas in the general population is not dependent on histopathological WHO grade, but may be gender-related.

Clinical features and long-term outcomes of pediatric meningiomas

OBJECTIVE

Pediatric meningiomas are relatively rare and have atypical clinical features compared to adults. The purpose of this work is to report our 15-year experience in the management of pediatric meningiomas and assess their clinical characteristics, pathological features, and prognostic factors.

METHODS

A total of 40 children (age ≤ 15 years) who were diagnosed as pediatric meningiomas were enrolled in this study. Patient information including clinical presentation, gender, age at time of diagnosis, histopathological features, tumor location, tumor volume, treatment methods, and follow-up data were extracted and analyzed.

RESULTS

The mean age at diagnosis was 10.78 ± 3.50 years (range 2-15 years) in 40 patients with a male to female ratio of 1:1.11. Headache, epilepsy, visual disturbance, and limb weakness are common clinical manifestations. Two patients had multiple intracranial meningiomas. Fourteen (33.3%) of pediatric meningiomas were high grade meningiomas. Seven patients (17.5%) were treated with STR, while GTR was achieved in 33 patients (82.5%). The mean follow-up period was 82.1 months (range 9-173 months). Recurrence occurred in 9 patients (22.5%), and 5 patients (12.5%) passed away.

CONCLUSION

The incidence of pediatric meningiomas increases with advancing age. In pediatric patients, the percentage of high-grade tumors is higher than adults. Younger children were more likely to have high-grade meningiomas, while patients with tumors located in skull base or parasagittal/falx tend to have low-grade meningiomas. The WHO grade III meningiomas were significantly correlated with poor prognosis. Adjuvant radiotherapy after surgery can improve prognosis and may be a potential treatment strategy in children with malignant meningiomas.

Adjuvant Radiotherapy in Grade II, Atypical Meningioma of the Skull Base

Introduction Atypical meningiomas (AM) are meningiomas that are more aggressive than their grade-I counterparts and have a higher rate of recurrence. The effect of adjuvant radiotherapy (ART) on AM of the skull base is not defined.

Methods A retrospective review of all AM's of the skull base primarily resected at our institution from 1996 to 2018 was completed. ART was defined as radiotherapy (RT) that occurred within 6 months of initial resection, regardless of Simpson's grade. Minimum time length of follow-up after resection was 2 years. Statistical analysis was performed using SAS.

Results There were a total of 59 skull base–located (SBL) AMs resected at our institution from 1996 to 2018. The average age of our cohort was 53.2 years. Gross total resection, defined as Simpson's grades I to III resection, was achieved in 36 (61%) of cases. Thirty-five of 59 (59%) patients received ART. Recurrence was observed in 14 patients (24%), and mean time to recurrence was 63.8 months. Patients who received ART had a lower observed rate of recurrence (8 vs. 46%); however, time to recurrence was not significantly different between the two populations.

Conclusion We observe that AM in the skull base location have higher recurrence rates than we would expect from grade-I meningioma. These data suggest that ART may offer benefit to the overall observed frequency of recurrence of SBL AM; however, the time to recurrence between patients who received ART and those who did not was not statistically significant in survival analysis.

Diagnostic nomogram model for predicting preoperative pathological grade of meningioma

Background

Meningioma is the most common primary tumor of the central nervous system. Preoperative diagnosis of high-grade meningioma is helpful for the selection of treatment options. The aim of our study is to establish a diagnostic nomogram model for preoperative prediction of the pathological grade of meningioma.

Methods

The predictive model was established from a cohort of 215 clinicopathologically confirmed meningioma between January 2012 and December 2017. Radiomic features were collected from preoperative magnetic resonance imaging (MRI) and computed tomography of patients with meningioma. The least absolute shrinkage and selection operator (LASSO) regression model was used for data dimension reduction and feature selection. Multivariate logistic regression was used to build a predictive model and presented as a nomogram. The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness. Internal validation was evaluated using bootstrapping validation.

Results

High-grade meningioma was observed in 47 patients (22%). The predictors included in the nomogram were tumor-brain interface, bone invasion, and tumor location. The final diagnostic model exhibited good calibration and discrimination with a C-index of 0.874 (95% confidence interval: 0.818–0.929) and a higher C-index of 0.868 in internal validation. Decision curve analysis (DCA) indicated that the nomogram is very useful in clinical practice.

Conclusions

This study provides a nomogram model with tumor-brain interface, bone invasion, and tumor location that can effectively predict the preoperative pathological grading of patients with meningioma and thus help clinicians provide more reasonable treatment strategies for meningioma patients.

Risk Factors for High-Grade Meningioma in Brain and Spine: Systematic Review and Meta-analysis

BACKGROUND

Histologic grade has important implications for the management in meningioma. It is important to understand the risk of high-grade meningioma (grades II and III). In this article, we systematically reviewed the histologic grade of meningioma depending on the location and sex and its relationship with recurrence.

METHODS

The PubMed and Embase databases were systematically searched until February 4, 2020. We included studies that were not restricted to specific anatomic locations, histologic grade, or the sizes of the tumors. The proportion of high-grade meningiomas depending on the location and sex and the odds ratio (OR) of recurrence were pooled using a random-effects model.

RESULTS

Outcome data were analyzed for 20,336 tumors from 34 studies. We found different proportions of high-grade meningiomas in the brain (12.8%) (95% confidence interval [CI], 10.5%-15.1%) versus the spine (2.4%) (95% CI, 1.0%-3.7%) (P < 0.01). Skull base meningiomas (8.7%) (95% CI, 5.8%-11.6%) had a lower proportion of high-grade meningiomas than non-skull base meningiomas (16.5%) (95% CI, 11.9%-21.1%) (P < 0.01). In addition, high-grade meningiomas were more likely to occur in male patients (18.0%) (95% CI, 10.1%-25.9%) than female patients (7.0%) (95% CI, 3.5%-10.6%) (P = 0.01). Higher rates of recurrence (OR = 13.83) were confirmed for high-grade meningiomas than grade I meningiomas (95% CI, 4.10-46.65) (P < 0.01).

CONCLUSIONS

This meta-analysis found that intracranial, nonskull base, and male sex are risk factors for high-grade meningioma, and high-grade meningioma had a much higher recurrence rate as compared with grade I meningioma.

Associations of pathological diagnosis and genetic abnormalities in meningiomas with the embryological origins of the meninges

Certain driver mutations and pathological diagnoses are associated with the anatomical site of meningioma, based on which the meninges have different embryological origins. We hypothesized that mutations and pathological diagnoses of meningiomas are associated with different embryological origins. We comprehensively evaluated associations among tumor location, pathological diagnosis (histological type), and genetic alterations including AKT1, KLF4, SMO, POLR2A, and NF2 mutations and 22q deletion in 269 meningioma cases. Based on the embryological origin of meninges, the tumor locations were as follows: neural crest, paraxial mesodermal, and dorsal mesodermal origins. Tumors originating from the dura of certain embryologic origin displayed a significantly different pathological diagnoses and genetic abnormality ratio. For instance, driver genetic mutations with AKT1, KLF4, SMO, and POLR2A, were significantly associated with the paraxial mesodermal origin (p = 1.7 × 10⁻¹⁰). However, meningiomas with NF2-associated mutations were significantly associated with neural crest origin (p = 3.9 × 10^–12). On analysis of recurrence, no difference was observed in embryological origin. However, POLR2A mutation was a risk factor for the tumor recurrence (p = 1.7 × 10⁻², Hazard Ratio 4.08, 95% Confidence Interval 1.28–13.0). Assessment of the embryological origin of the meninges may provide novel insights into the pathomechanism of meningiomas.

World Health Organization Grade III Meningiomas: A Retrospective Study at an Academic Medical Center

BACKGROUND

Meningiomas are the most common primary brain tumors and are generally considered benign. However, a rare subgroup of meningiomas, classified as World Health Organization (WHO) grade III meningiomas, can show extremely aggressive behavior and high rates of recurrence. Despite ongoing research, data on the clinical outcome of this subgroup of meningiomas are still limited.

METHODS

Medical records of patients with WHO grade III meningiomas diagnosed between 2000 and 2018 at the Coimbra University Hospital Center were retrospectively reviewed and several variables of interest and their relation to patients' survival were analyzed.

RESULTS

Of the 26 patients included in the final analysis, 23 had anaplastic meningiomas, 2 had papillary meningiomas, and 1 had a rhabdoid meningioma. Median overall survival and median progression-free survival were 2.45 and 1.22 years, respectively. Overall survival at 1, 2 and 5 years was 73%, 57%, and 35%, respectively. Adjuvant radiotherapy correlated with improved survival for subtotally resected meningiomas but not for gross totally resected meningiomas. There was a trend toward improved overall survival with gross total resection versus subtotal resection, but this difference failed to reach statistical significance.

CONCLUSIONS

This study provides insight into the clinical outcomes of WHO grade III meningiomas and suggests that adjuvant radiotherapy may not be beneficial for patients who underwent gross total resection. This rare subset of meningiomas still portends a devastating prognosis and the impact of extent of resection and adjuvant therapies in these patients needs further clarification.

High-grade spheno-orbital meningioma in patients with systemic lupus erythematosus: Two case reports and literature review

Background:

Spheno-orbital meningiomas (SOMs) are often benign. The association of meningioma and systemic lupus erythematosus (SLE) is rarely discussed in the literature. Here, we report two patients with high-grade, SOMs with a prolonged history of SLE and review the literature.

Case Description:

The first case is a 52-year-old female patient with a 15-year history of SLE diagnosis who was referred to our center with a 1-year history of proptosis and excessive tearing of the left eye. This patient was operated for the left SOM with histopathological diagnosis of the World Health Organization (WHO) Grade III rhabdoid meningioma. The second case is a 36-year-old female patient with a 12-year history of SLE diagnosis who presented to our clinic with a 5-year-history of progressive right eye proptosis and occasional headaches. She was operated for the right SOM with histopathological diagnosis of the WHO Grade II chordoid meningioma.

Conclusion:

Rhabdoid and chordoid SOMs are uncommon and no previous report discussed their occurrence in patients with SLE. The association of high-grade meningiomas and SLE deserves further exploration.

A Novel Scoring System Based on Preoperative Routine Blood Test in Predicting Prognosis of Atypical Meningioma

Purpose

The aim of this study was to explore the correlation and clinical significance of preoperative fibrinogen and neutrophil-lymphocyte ratio (F-NLR) scoring system with 3-year progression-free survival (PFS) of patients with atypical meningioma.

Materials and Methods

Clinical, pathological, radiological, and laboratory variables were collected to analyze their correlation with 3-year PFS in the training set with 163 patients. Patients were classified by different F-NLR scores (0, 1, or 2). External validation for the predictive value of F-NLR scoring system was performed in the validation set with 105 patients.

Results

Overall, 37.3% (100 of 268) of the enrolled patients were male. The scoring system showed good performance in predicting 3-year PFS (AUC = 0.872, 95%CI = 0.811–0.919, sensitivity = 66.1%, specificity = 93.3%, and Youden index = 0.594). DeLong’s test indicated that the AUC of F-NLR scoring system was significantly greater than that of fibrinogen level and NLR (Z = 2.929, P = 0.003; Z = 3.376, P < 0.001). Multivariate Cox analysis revealed that tumor size (HR = 1.39, 95%CI = 1.10–1.76, P = 0.007), tumor location (HR = 3.11, 95%CI = 1.60–6.95, P = 0.001), and F-NLR score (score of 1: HR = 12.78, 95%CI = 3.78–43.08, P < 0.001; score of 2: HR = 44.58, 95%CI = 13.02–152.65, P < 0.001) remained significantly associated with 3-year PFS. The good predictive performance of F-NLR scoring system was also demonstrated in the validation set (AUC = 0.824, 95%CI = 0.738–0.891, sensitivity = 62.5%, specificity = 87.9%, and Youden index = 0.504).

Conclusion

Our study confirmed the correlation and clinical significance of preoperative F-NLR scoring system with 3-year PFS of patients with atypical meningioma. A prospective and large-scale study is required to validate our findings.

Multicentric and diffuse recurrences of meningiomas

Background: Meningiomas recur with a rate of 10-32% at 10 years. Several features influence the risk of recurrence.Objective: To define the pathological and surgical features at risk of multicentric-diffuse versus local-peripheral recurrence.Methods: Thirty-three patients operated on for intracranial meningiomas who experienced multicentric-diffuse recurrence were retrospectively analyzed. The data of these patients were compared to those of 50 patients who experienced local-peripheral recurrence. The analyzed factors included age and sex, tumor location and shape, brain-tumor interface, entity of resection, WHO grade, Ki67 MIB1, progesterone receptor (PR) expression, number of reoperations, progression of WHO grade, and outcome.Results: Meningiomas which recurred in multicentric-diffuse pattern showed at initial surgery a significantly higher rate of flat-shaped tumors (p = .0008) and of cases with Ki67 Li ≥ 4% (p = .037) than those which recurred in localized-peripheral pattern, whereas other factors did not significantly differ. Among patients with multicentric-diffuse recurrences, 25 underwent one to three reoperations; 17 among them (66%) are alive with local tumor control or slow progression 2-25 years after the initial surgery versus only 2 out of 8 who did not undergo surgery.Conclusions: Flat-shaped meningiomas and those with Ki67 Li ≥ 4% are at higher risk of multicentric-diffuse recurrence. Multiple reoperations over a period of several years may obtain rather long survivals in selected patients with prevalent intradural, not anaplastic tumors and not too extensive dural infiltration.

Evaluation of Epidemiologic Factors, Radiographic Features, and Pathologic Findings for Predicting Peritumoral Brain Edema in Meningiomas

BACKGROUND

Despite several treatment options that are available for meningiomas, surgery is the only method currently practiced. Peritumoral brain edema (PTBE) in meningiomas causes difficulty marginalizing the dissection in an intraoperative setting.

PURPOSE

To evaluate whether the epidemiological variables, imaging characteristics, and pathologic parameters are correlated with the presence of PTBE in meningiomas.

STUDY TYPE

Retrospective study from 2015 to 2018.

SUBJECTS

In all, 550 patients with histopathologically confirmed meningioma were included. After exclusion of patients with extradural, spinal, and intraventricular meningiomas and those with image artifacts, a total of 441 patients were included in the final analysis.

FIELD STRENGTH/SEQUENCE

Images were performed with 3T MR scanners and axial/sagittal T₁ WI, axial/coronal T₂ WI and axial/sagittal/coronal contrast-enhanced T₁ WI after administration of 0.1 mmol/kg of body weight of Gd-DTPA.

ASSESSMENT

Fourteen variables were patients' age, sex, skull changes, calcification, density, location, margin, volume, cerebrospinal fluid (CSF) cleft, signal intensity (SI) on T₂ WI, degree and pattern of contrast enhancement, WHO histological classification, and Ki-67 labeling index.

STATISTICAL TESTS

The relationship between each factor and the formation of PTBE was examined by multivariate logistic regression analysis.

RESULTS

After multivariate logistic regression, the absence of CSF cleft (odds ratio [OR]: 63.43, 95% confidence interval [CI]: 27.24-121.42, P = 1.2 × 10^-8 ), non-skull base location (OR: 15.32, 95% CI: 5.81-28.23, P = 0.0008), high SI on T₂ WI (OR: 5.05, 95% CI: 2.27-14.88, P = 0.01), and G I uncommon subtypes (OR: 4.75, 95% CI: 1.42-15.94, P = 0.01) were found to be significant independent factors associated with the occurrence of PTBE in meningiomas. In patients with PTBE-positive meningiomas, there was no significant correlation between the volume of PTBE and the volume of the tumor (r = 0.17, P = 0.60).

DATA CONCLUSION

These factors may be suggestive of anticipating the formation of PTBE.

LEVEL OF EVIDENCE

3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;52:174-182.

Angiography and embolization of meningiomas

The preoperative embolization of meningiomas has been part of the surgical treatment of large meningiomas for over 45 years. During that time there have been huge advances in the field of endovascular surgery with respect to techniques and instrumentation. Angiography and embolization are usually reserved for the largest tumors where there are concerns over potential blood loss with surgical excision. In this chapter, we discuss the technical aspects of angiography and embolization as well as results and complications.

Fibrous Meningioma with Skull Invasion

In patients with meningiomas, the presence of skull invasion is known to be a predictor of aggressive clinical behavior, which may negatively influence patient outcomes. In the present report, we discuss a case of fibrous meningioma with skull invasion. A 42-year-old woman was referred to our department presenting with hyperostosis in the right parietal bone. T1-weighted magnetic resonance imaging with gadolinium enhancement revealed prominent enhancement of the intraosseous lesion and dura mater. Following the removal of the tumor body and bone lesion, we performed immunohistochemical staining for osteopontin (OPN), matrix metalloproteinase- 2 (MMP2), and integrin β-1 (CD29). The tumor body was immunoreactive for OPN and CD29, but not MMP2, whereas, the bone lesion was immunoreactive for all the three antigens. The present case suggests that OPN, MMP2, and CD29 play key regulatory roles in bone invasion.

WHO grade, proliferation index, and progesterone receptor expression are different according to the location of meningioma

BACKGROUND

Meningiomas may show a different WHO grade and variable biological and clinical behaviors. The aim of the present study is to assess whether WHO grade, proliferation index, progesterone receptor (PR) expression, histological subtype, neuroradiological features, and the recurrence rate differ depending on the tumor location.

METHODS

Three hundred meningiomas operated on from 2006 to 2016 were reviewed. The WHO grade (2007 classification), Ki67-MIB1, progesterone receptor expression, and histological subtype were reexamined and correlated to the meningioma location, classified as medial skull base, lateral skull base, non-skull base, and spinal.

RESULTS

Non-skull base and lateral skull base meningiomas showed significantly higher rates of atypical WHO II forms (34% and 25.5% respectively) than medial skull base (12.5%) and spinal ones (7%) (p = 0.0003) and also higher rates of tumors with Ki67-Li > 4% (42% and 38% vs 22% and 14%) (p = 0.0031). The rate of meningiomas with PR expression ≤ 50% was significantly lower in medial skull base (25%) than in non-skull base (48%) (p = 0.009). Meningothelial and transitional meningiomas were more frequent at the skull base (68.5% and 54.5%, respectively), the fibroblastic subtype at the non-skull base (48.5%), and the psammomatous at the spinal canal (50%) (p < 0.00001). Medial skull base and spinal meningiomas showed significantly lower size (p < 0.00001), lower rates of cases with lost arachnoid interface (p = 0.0022), and significantly lower recurrence rates (p = 0.0035) than lateral skull base and non-skull base meningiomas.

CONCLUSION

Medial skull base meningiomas show lower size, lower rate of atypical forms, lower Ki67-Li values, and significantly higher PR expression than those at the lateral skull base and non-skull base. This corresponds to lesser aggressiveness and lower recurrence rates.

Management of pediatric CNS meningiomas: CCHE-57357 experience in 39 cases

PURPOSE

Our aim is to present our experience in the management of pediatric meningiomas in the largest referral center in Egypt for pediatric tumors focusing on variables including clinical picture, anatomic location, histopathology, treatment strategies, and outcome together with their possible correlation to prognosis.

METHODS

We retrospectively reviewed the medical records of 39 pediatric patients who were treated for CNS meningiomas in Children's Cancer Hospital-Egypt (CCHE-57357) 2007-2017.

RESULTS

The prevalence of pediatric meningioma was 1.42%. Four cases had type 2 neurofibromatosis (NFII). The mean age was 8.19 years. The presence of NFII was associated with challenging multiple lesions, older age of presentation and poorer prognosis and functional outcome. Convexity was the commonest location. Gross total resection (GTR) was achieved in 28 cases, subtotal resection (STR) in 8 cases, and biopsy was decided in 3 patients. Histopathological examination revealed WHO grade I in 16 patients and higher grades in 23 patients (59%). The 5-year overall survival (OS) rate was 87.8% while the 5-years event-free survival (EFS) rate was 85.6%. Tumor location, histopathology, and clinical presentation were not statistically correlated to prognosis.

CONCLUSIONS

Pediatric CNS meningiomas are uncommon pediatric tumors but of an aggressive clinical and pathological behaviors as compared to adult meningiomas. The presence of NFII is associated with a poorer prognosis and functional outcomes. Although being challenging, the maximum and safe surgical excision should be exercised even in recurrent cases in order to achieve the best outcome. Adjuvant radiotherapy provides good tumor control for inoperable residual atypical or anaplastic meningiomas.

Recurrence of spinal meningiomas: analysis of the risk factors

Objective: Spinal meningiomas are slow-growing tumors with low recurrence rate after complete resection. The aim of this study is to investigate the risk factors correlated to the recurrence.Material and Methods: Six patients with spinal WHO grade I meningiomas which recurred after complete resection were reviewed and compared to 50 patients with no recurrence; the data were also compared with those of 50 intracranial meningiomas which recurred and 50 which did not recur after complete resection. The investigated factors included age and sex, tumor location and size, type of arachnoid interface, entity of resection (Simpson I or II), tumor consistency and vascularity, histological type, Ki-67 MIB-1, progesterone receptor (PR) and estrogen receptor (ER) expression. The data were statistically analyzed with the Kaplan-Meier method.Results: The statistical analysis showed that the presence of arachnoidal invasion (p = 0.023) and higher Ki-67 LI (p < 0.0001) were the only two significant risk factors for recurrence for both spinal and intracranial meningiomas. Large tumor size (p = 0.012), Simpson grade II resection (p = 0.03) and the absence of PR expression (p < 0.0001) were significant risk factors for recurrence of intracranial but not spinal meningiomas. Finally, age and sex, tumor location, consistency and vascularity, histological type, and ER expression were not correlated to recurrence for both localizations.Conclusions: The proliferation index Ki-67 and the arachnoid invasion are the risk factors for recurrence of spinal meningiomas, whereas tumor size, dural resection and PR expression are not significant. The small tumor size and the limited dural invasion may contribute to explain the lower recurrence rate.

Prediction of Recurrence in Parasagittal and Parafalcine Meningiomas: Added Value of Diffusion-Weighted Magnetic Resonance Imaging

BACKGROUND

Parasagittal and parafalcine (PSPF) meningiomas recur more frequently than other intracranial meningiomas owing to the difficulty in achieving gross total resection. The present study investigated the preoperative magnetic resonance imaging (MRI) features for the prediction of progression/recurrence (P/R) in benign PSPF meningiomas with an emphasis on the apparent diffusion coefficient (ADC) values.

METHODS

We retrospectively investigated the preoperative MRI features for the prediction of P/R in benign (World Health Organization grade I) PSPF meningiomas. Only patients who had undergone preoperative and postoperative MRI follow-up studies for ≥1 year were included. From October 2006 to December 2015, 48 patients with a diagnosis of benign PSPF meningioma were included (median follow-up period, 42.5 months). Of these 48 patients, 12 (25%) developed P/R (median time to P/R, 23 months).

RESULTS

PSPF meningiomas in male patients, subtotal resection, large tumor diameter, high diffusion-weighted imaging signal, and lower ADC values or ratios were significantly associated with P/R (P < 0.05). The cutoff points of the ADC value and ADC ratio for the prediction of P/R were 0.83 × 10^-3 mm²/second and 0.99, with an area under the curve of 0.82 and 0.83, respectively (P = 0.001). On multivariate Cox proportional hazards analysis, male sex and low ADC values (<0.83 × 10^-3 mm²/second) were high-risk factors for P/R, with a hazard ratio of 12.37 and 30.2, respectively (P < 0.05). Kaplan-Meier analysis showed that lower ADC values and ratios predicted for significantly shorter progression-free survival (P < 0.05).

CONCLUSIONS

The preoperative ADC values and ratios for the prediction of P/R offer additional valuable information for the treatment planning for PSPF meningiomas.

Clinical and prognostic features of spinal meningioma: a thorough analysis from a single neurosurgical center

PURPOSE

The aim of this study was to thoroughly analyze the clinical characteristics of a large cohort of spinal meningioma (SM) from a single neurological center and identify risk factors associated with worse progression free survival and neurological function outcome.

METHODS

Clinical information was retrieved from 483 SM and 9806 cranial meningioma cases who were operated in our center between 2003 and 2013. 194 SM patients who were followed at the main branch were used for prognostic analyses that included both recurrence free survival and neurological functions based on Modified McCormick scale (MMS).

RESULTS

Females were predominant (P < 0.001). High grade tumors were not common (WHO grade II, 2.9%; grade III, 1.7%), while the clear cell subtype was frequent within grade II SMs (6/14, 42.9%). Macroscopic total resection was achieved in all SMs (Simpson grade I, 30.9%; grade II, 65.5%; grade III, 3.6%) with a low complications rate (4.6%) and provided neurological improvement in 80 patients (41.2%). Recurrence was seen in 9 cases (4.6%) and associated with high WHO grade, male, prior recurrence, and Simpson grade III. High WHO grade and high Ki-67 index were identified to be independent factors predictive of both neurological function deterioration and impaired post-operative neurological status.

CONCLUSIONS

Our analysis of the largest SM cohort in scale from a single institution offers a comprehensive view of the clinical characteristics of surgically treated SM, revealing the distinct biology of SM in comparison to its cranial counterparts, and providing guidance to improve surgical management of SM.

Spheno-Orbital Meningiomas: An Analysis Based on World Health Organization Classification and Ki-67 Proliferative Index

PURPOSE

To evaluate the clinical behavior of spheno-orbital meningiomas with regard to World Health Organization (WHO) tumor grade and Ki-67, a cellular marker of proliferation.

METHODS

A retrospective review over a 16-year period of the demographic, clinical, radiographic, and surgical data of all patients with spheno-orbital meningioma who underwent surgical resection. Tumor specimens were examined histologically using the current WHO 2016 classification and immunohistochemically using Ki-67/MIB-1 monoclonal antibody.

RESULTS

Thirty-eight patients met all inclusion criteria: 78.9% of tumors were WHO grade I with a mean Ki-67 of 3.76, and 93% of patients were clinically stable at last follow up; 10.5% of lesions were WHO grade II (atypical) with a mean Ki-67 of 14.93, and 10.5% of lesions were WHO grade III (anaplastic) with a mean Ki-67 of 58.3. All grade II and III meningiomas exhibited an aggressive clinical course. There were statistically significant correlations between disease clinical progression and WHO tumor grade (p < 0.001), between disease clinical progression and Ki-67 (p < 0.001), and between increasing Ki-67 index and higher WHO grade (p < 0.001). For WHO grade I lesions, a Ki-67 of ≥3.3 correlated with recurrence (p = 0.0256). Overall, disease-specific mortality occurred in 5 (13%) patients.

CONCLUSIONS

Ki-67 index is a valuable marker to use in conjunction with WHO grade to predict meningioma behavior, particularly in histologically borderline lesions, and possibly to identify a subset of WHO grade I tumors at risk of recurrence. This combination of methods can aid in tailoring treatment and surveillance strategies.

Boron Neutron Capture Therapy for High-Grade Skull-Base Meningioma

Objectives  Boron neutron capture therapy (BNCT) is a nuclear reaction-based tumor cell-selective particle irradiation that occurs when nonradioactive Boron-10 is irradiated with low-energy neutrons to produce high-energy α particles (10B [ n , α] 7Li). Possible complications associated with extended surgical resection render high-grade meningioma (HGM) a challenging pathology and skull-base meningiomas (SBMs) even more challenging. Lately, we have been trying to control HGMs using BNCT. This study aims to elucidate whether the recurrence and outcome of HGMs and SBMs differ based on their location. Design  Retrospective review. Setting  Osaka Medical College Hospital and Kyoto University Research Reactor Institute. Participants  Between 2005 and 2014, 31 patients with recurrent HGM (7 SBMs) were treated with BNCT. Main Outcome Measures  Overall survival and the subgroup analysis by the anatomical tumor location. Results  Positron emission tomography revealed that HGMs exhibited 3.8 times higher boron accumulation than the normal brain. Although tumors displayed transient increases in size in several cases, all lesions were found to decrease during observation. Furthermore, the median survival time of patients with SBMs post-BNCT and after being diagnosed as high-grade were 24.6 and 67.5 months, respectively (vs non-SBMs: 40.4 and 47.5 months). Conclusions  BNCT could be a robust and beneficial therapeutic modality for patients with high-grade SBMs.

Prediction of progression in skull base meningiomas: additional benefits of apparent diffusion coefficient value

A subset of benign (WHO grade I) skull base meningiomas show early progression/recurrence (P/R) in the first years after surgical resection. Besides, complete surgical resection may be difficult to achieve safely in skull base meningiomas due to complex neurovascular structures. The one main challenge in the treatment of skull base meningiomas is to determine factors that correlate with P/R. We retrospectively investigated the preoperative CT and MR imaging features for the prediction of P/R in skull base meningiomas, with emphasis on quantitative ADC values. Only patients had postoperative MRI follow-ups for more than 1 year (at least every 6 months) were included. From October 2006 to December 2015, total 73 patients diagnosed with benign (WHO grade I) skull base meningiomas were included (median follow-up time 41 months), and 17 (23.3%) patients had P/R (median time to P/R 28 months). Skull base meningiomas with spheno-orbital location, adjacent bone invasion, high DWI, and lower ADC value/ratio were significantly associated with P/R (P < 0.05). The cut-off points of ADC value and ADC ratio for prediction of P/R are 0.83 × 10^- 3 mm²/s and 1.09 respectively, with excellent area under curve (AUC) values (0.86 and 0.91) (P < 0.05). In multivariate logistic regression, low ADC values (< 0.83 × 10^- 3 mm²/s) and adjacent bone invasion are high-risk factors of P/R (P < 0.05), with odds ratios of 31.53 and 17.59 respectively. The preoperative CT and MRI features for prediction of P/R offered clinically vital information for the planning of treatment in skull base meningiomas.

[Comparative analysis of Grade I vs Grade II intracranial Meningiomas in a retrospective series of 63 patients]

Objective

We aimed to demonstrate the differences between grade I and II (OMS classification) of intracranial meningiomas. We evaluate their location, Simpson resection grade, re-operations rate, adjuvant treatment and patient outcomes.

Methods

We conduct a retrospective review of Sixty- three clinical records of patients who were diagnosed with meningiomas grade I and II (OMS) between 2009-2015 and received surgical treatment at our Hospital. We evaluated different variables such as age, sex, histological type, Simpson grade resection, location, symptoms, radiotherapy, follow-up, mortality rate and patient outcome. The main aim was to establish the differences between these intracranial tumors.

Results

A total of sixty-three patients diagnosed with meningiomas and received surgical treatment; fifty-one were grade I and thirteen with grade II. There were no differences in the rate between man and women. The average age for both types of meningiomas was 57 years old. The typical meningiomas were located in 55% of the cases outside the cranial base vs. 91.6% of the atypical meningiomas (P = 0.03). Typical meningioma had a Simpson resection grade of I, II and III in 74.5% against 58.3% of the atypical (P = 0.2). The atypical meningioma in 33% had more than one-stage surgery vs. 9.8% of the typical (P = 0.03). The patients with a typical meningioma showed a good outcome in 86.2% vs. 53.8 of the grade II (P = 0, 01). The typical meningiomas showed a good outcome in 82.2% of the cases vs. 53.8% of the atypical. The grade II meningiomas received adjuvant treatment in 33.3%, while the grade I only 1.9%.

Conclusions

The atypical intracranial meningiomas have a worse outcome compared with the typical kind and a higher incidence of re-operations. These tumors have a preference for a location outside the cranial base. Concluding that the location could be a risk factor.

World Health Organization Grade II Meningiomas: The Role of Adjuvant/Salvage Gamma Knife Surgery After Initial Surgery and Prognostic Factor Assessment

OBJECTIVE

This study was performed to evaluate the efficiency of Gamma Knife surgery (GKS) on reducing recurrence of World Health Organization (WHO) grade II meningiomas after surgery and to define the risk factors associated with tumor recurrence/progression and patient's death.

METHODS

This retrospective study included 75 patients who were diagnosed with WHO grade II meningiomas after initial surgery. The Kaplan-Meier method with a log-rank test was used to calculate the survival curves. Univariate and multivariate Cox proportional hazards model were used to identify the risk factors associated with tumor recurrence/progression and patient's death.

RESULTS

The median follow-up period was 70 months. The overall survival (OS) was 97.2% at 2 years and 89.8% at 5 years. The progression-free survival (PFS) at 1, 3, and 5 years was 89.3%, 72.6%, and 59.3%, respectively. Comparing the effects on PFS and OS between different groups, there were no statistically significant differences between the surgery-alone group and the surgery with adjuvant/salvage GKS group (P = 0.512; P = 0.949). In multivariate Cox proportional hazards model analysis, extent of resection (P = 0.001) and tumor location (P = 0.015) were associated with tumor recurrence; only histologic subtypes (P = 0.005) were associated with patient's death.

CONCLUSIONS

There was no significant PFS or OS benefit for patients with WHO grade II meningiomas treated with adjuvant/salvage GKS postoperatively. Convexity meningiomas with gross total resection tended to benefit PFS. We suggest trying to achieve maximum safe gross total resection for patients with WHO grade II meningiomas, then following up closely.

Intracranial Meningioma in Patients Age <35 Years: Evolution of the Disease in the Era of Human Immunodeficiency Virus Infection

BACKGROUND

Intracranial meningiomas are most common among patients in their fifth to seventh decade of life and rare in children and young adults. They constitute 1.5% of all neoplasms in patients age <20 years, but account for 13.5% of all neoplasms in patients age 20-34 years. They are often associated with hereditary or familial syndromes in children and young adults, and tend to be of high grade. Here we describe the histopathological subtypes of intracranial meningioma between human immunodeficiency virus 1 (HIV-1)-seropositive patients and the general population with intracranial meningiomas 35 years old and younger.

METHODS

Data were collected from all consecutive patients age ≤35 years diagnosed with intracranial meningioma between May 2003 and May 2015. Age was categorized as <20 years, 21-30 years, and >30 years. Histopathological grade was classified according to the 2000 World Health Organization (WHO) grading system as grade I, II, or III. Patients were grouped into an HIV-1-seropositive group and the general population, presumed seronegative. WHO grade II/III meningioma represented high-grade meningioma.

RESULTS

HIV-1-seropositive status was associated with increased risk of the development of high-grade (WHO grade II/III) meningioma (odds ratio, 2.9; 95% confidence interval, 1.06-8.09; P = 0.04) compared with the general population of patients with meningiomas. No significant associations were found between WHO grade and age, sex, ethnicity/race, or location.

CONCLUSIONS

Intracranial meningiomas in young HIV-1-positive patients tend to be of high grade; therefore, conservative or noninvasive therapies should be offered with caution and only after tissue diagnosis has confirmed benign WHO grade.

Prediction of Histological Grade and Completeness of Resection of Intracranial Meningiomas: Role of Peritumoural Brain Edema

BACKGROUND

Meningioma is the commonest primary intracranial tumour in adults. Excision is curative for low grade meningioma, whereas high-grade meningioma requires adjuvant therapy following surgery. Several studies have examined the association between peritumoural brain Edema - a common feature in meningioma - and histological grading with mixed results. The present study attempted to elucidate this association and if peritumoural brain Edema affects the intra-operative judgement of surgeons on the completeness of resection.

METHODS

An observational study was conducted among those who underwent surgery for meningioma. Eighteen subjects were recruited each for low- and high-grades, respectively. Magnetic resonance imaging (MRI) prior to surgery was employed for interpreting the Edema index and MRI after surgery was used to determine residual tumour.

RESULTS

Median age was 50 years, male to female ratio was 1:3.5, 69.4% had peritumoural brain Edema and 75% had reported gross resection. Among the reported gross total resection cases, 40.7% had residual tumour. Analysis showed statistically significant association between peritumoural brain Edema (P = 0.027) and tumour volume (P = 0.001) with high-grade meningioma, however multivariate analysis did not present any association. No association was noted between judgement of tumour resection by surgeons and peritumoural brain Edema.

CONCLUSION

Odds ratio for peritumoural brain Edema remained high and the tumour volume exhibited marginal P-value marginal significance for prediction of high grade meningioma. These two factors may still contribute to the tumour grade and should be included in further studies on the prognosis of meningioma.

Surgery for meningioma in the elderly and long-term survival: comparison with an age- and sex-matched general population and with younger patients

OBJECTIVE

The purpose of this study was to compare long-term prognosis after meningioma surgery in elderly and younger patients as well as to compare survival of elderly patients with surgically treated meningioma to survival rates for the general population.

METHODS

Five hundred meningioma patients (median follow-up 90 months) who underwent surgery between 1994 and 2009 were subdivided into “elderly” (age ≥ 65 years, n = 162) and “younger” (age < 65 years, n = 338) groups for uni- and multivariate analyses. Mortality was compared with rates for the age- and sex-matched general population.

RESULTS

The median age at diagnosis was 71 in the elderly group and 51 years in the younger group. Sex, intracranial tumor location, grade of resection, radiotherapy, and histopathological subtypes were similar in the 2 groups. High-grade (WHO Grades II and III) and spinal tumors were more common in older patients than in younger patients (15% vs 8%, p = 0.017, and 12% vs 4%, p = 0.001, respectively). The progression-free interval (PFI) was similar in the 2 groups, whereas mortality at 3 months after surgery was higher and median overall survival (OS) was shorter in older patients (7%, 191 months) than in younger patients (1%, median not reached; HR 4.9, 95% CI 2.75–8.74; p < 0.001). Otherwise, the median OS in elderly patients did not differ from the anticipated general life expectancy (HR 1.03, 95% CI 0.70–1.50; p = 0.886). Within the older patient group, PFI was lower in patients with high-grade meningiomas (HR 24.74, 95% CI 4.23–144.66; p < 0.001) and after subtotal resection (HR 10.57, 95% CI 2.23–50.05; p = 0.003). Although extent of resection was independent of perioperative mortality, the median OS was longer after gross-total resection than after subtotal resection (HR 2.7, 95% CI 1.09–6.69; p = 0.032).

CONCLUSIONS

Elderly patients with surgically treated meningioma do not suffer from impaired survival compared with the age-matched general population, and their PFI is similar to that of younger meningioma patients. These data help mitigate fears concerning surgical treatment of elderly patients in an aging society.

A comparison of clinicopathological features and surgical outcomes between pediatric skull base and non-skull base meningiomas

OBJECT

The purpose of this study is to analyze and compare the clinicopathological characteristics and surgical outcomes between skull base and non-skull base meningiomas in pediatric population.

METHODS

We retrospectively analyzed a total of 140 cases of pediatric meningiomas surgically treated in our department from January 2005 to July 2015 and compared the clinicopathological characteristics and surgical outcomes between skull base and non-skull base meningiomas.

RESULTS

Of all the pediatric meningiomas, 50 (35.8 %) were located at the skull base and 90 (64.2 %) were located at the non-skull base. Skull base and non-skull base meningiomas had a similar sex distribution (male/female = 1:1 in skull base meningiomas and male/female = 1.5:1 in non-skull base meningiomas) (P = 0.288) and high-grade meningioma occurrence rate (P = 0.569). In addition, the mean age of non-skull base meningiomas was 12.5 years which was younger than that of skull base meningiomas (14.2 years) (P = 0.019), and the preoperative tumor size was smaller in skull base (mean size = 4.7 cm in skull base meningiomas and mean size = 5.7 cm in non-skull base meningiomas) (P = 0.020). Gross total resection was achieved in 64 non-skull base patients (73.9 %) and 26 skull base patients (52 %) (P = 0.046). Patients with gross total resection had better progression free survival (PFS) than those with subtotal resection.

CONCLUSION

Pediatric skull base and non-skull base meningiomas are similar in sex distribution and high-grade meningioma occurrence rate. In comparison with non-skull base ones, pediatric skull base meningiomas occur at elder age and are smaller in size and they are more likely to be incompletely resected. Gross total resection and early treatment are recommended to prolong PFS of pediatric patients.

Analysis of the results of recurrent intracranial meningiomas treated with re-radiosurgery

OBJECTS

Meningioma is the most common intracranial neoplasm, comprising approximately 30% of all primary intracranial tumors (Claus et al., 2005) [1]. Treatment options include observation, microsurgical resection, stereotactic radiosurgery (SRS), and whole brain radiation therapy (WBRT). Gamma knife radiosurgery (GKRS) is a very effective treatment for intracranial meningiomas; previous studies showed the tumor control rate at 5-10 years of follow-up as 84.3%-100% in all cases (Feigl et al., 2005; Linskey et al., 2005; Malik et al., 2005; Aichholzer et al., 2000; Hakim et al., 1998; Chang and Adler 1997; Lunsford, 1994; Ganz et al., 1993) [2-9]. Many studies have discussed issues like optimal dose, conformal configurations, and adverse effects to improve the treatment result with GKRS (Malik et al., 2005; Kenai et al., 2005; Rowe et al., 2004; Shrieve et al., 2004) [4,10-12]. There are some cases in which the radiosurgery result is unfavorable and perhaps further treatment is needed. In these cases, re-radiosurgery can be an option. However, there have not been comprehensive studies discussing the issues of re-radiosurgery. Therefore, we analyzed the result of re-radiosurgery for recurrent meningiomas and their impact on clinical outcomes.

METHODS

From 1995 to 2015, we retrospectively reviewed 1163 patients who underwent GKRS for intracranial meningioma at the Asan Medical Center. Patients with multiple meningiomas or a follow-up with a period of less than a year were excluded from this study. Finally, 865 patients were enrolled in this study. Clinical symptoms and brain magnetic resonance imaging (MRI) scans were assessed by neurosurgeons. When tumor size increased together with newly developed neurologic symptoms, further management, such as microsurgical resection or SRS, was considered. Histologic analysis of the resected tumors was performed by neuropathologists. Clinical data, including patient's sex, age, and tumor locations were recorded. Treatment data included tumor volume, tumor grade, radiation dose, and presence of edema. Final outcome data including follow-up period, time to progression, interval between first and second radiosurgery courses and interval between microsurgery and radiosurgery were obtained.

RESULTS

Among 865 patients, tumor recurrence was found in 63 patients (7.28%). Seven patients showed transient tumor growth after GKRS. These patients have been under close observation without any further treatments. Fifty-six patients (6.47%) showed permanent tumor growth on follow-up MRI. Thirty-three patients from this group underwent repeated radiosurgery owing to tumor growth, resulting in a re-irradiation rate of 3.82% at our radiosurgery center. The other 23 patients were treated using methods other than re-radiosurgery. Among the 33 patients, 25 underwent microsurgical resection prior to their initial course of GKRS, and the other 8 were treated with re-radiosurgery only. An analysis was performed to determine factors that may have a role in treatment results. Of the many variables, tumor grade (p=0.004, Fisher's exact test) was the only significant factor for progression-free survival (PFS). Thirteen patients with unbiopsied or benign meningioma showed stable tumor size, while there was tumor growth in 8 patients. Among high-grade meningioma patients, 3 and 9 showed stable disease and tumor growth, respectively. As a result of re-radiosurgery, 11 out of 17 patients showed tumor growth and needed further treatments; this involved a third GKRS for 4 patients, microsurgical resection for 6 patients, and cyber knife radiosurgery (CKRS) for 1 patient. Four patients from this group were also treated with WBRT.

CONCLUSION

We analyzed the results of re-radiosurgery for recurrent meningiomas and observed that World Health Organization (WHO) grade II and III was significantly associated with a lower PFS rate compared with low-grade meningiomas (p=0.004). Conversely, patients with benign meningioma or unbiopsied tumors had much better results. Hence, re-radiosurgery is recommended for patients with unknown or benign meningiomas if their first GKRS result is unsatisfactory. However, re-radiosurgery should be considered carefully for recurrent high-grade tumors. Owing to the small number of recurrent meningioma patients treated with re-radiosurgery, further studies are required to delineate the role of this treatment.

A study of prognostic factors in 45 cases of atypical meningioma

BACKGROUND

Atypical meningioma differs from Grade I meningioma in terms of high recurrence rate and short life expectancy. We evaluated the clinical course of atypical meningioma and investigated prognostic factors affecting its outcomes.

METHOD

We reviewed 45 patients with atypical meningioma who underwent surgical intervention between January 2000 and December 2013. The mean age of the patients and mean follow-up period was 58.7 years and 81.0 months, respectively. Analyses included factors such as patient age, gender, location and size of tumor, extent of surgical resection (Simpson Grading System), and MIB-1 labeling index (LI). Univariate analysis was used to detect prognostic factors associated with recurrence and survival.

RESULTS

The 5-year recurrence-free rate for all 45 patients was 58.4 %; 5- and 10-year survival rates were 83.2 % and 79.9 %, respectively. In univariate analyses, age >60 years, and MIB-1 LI correlated with disease recurrence, whereas age >60 years, subtotal surgical resection, MIB-1 LI, and indication for radiotherapy correlated with death. MIB-1 LI levels higher than 12.8 % and 19.7 % predicted recurrence and death, respectively. In our cohort, 26 patients received postoperative radiotherapy including conventional radiation (n = 21) or gamma knife radiosurgery (n = 5). Postoperative radiotherapy did not decrease recurrence rates in our cohort (p = 0.63). Six and two patients who died during the study period underwent conventional radiation and radiosurgery, respectively.

CONCLUSIONS

Age, male gender, extent of surgical resection, and higher MIB-1 LI influenced the outcome of atypical meningioma. In our cohort, postoperative radiotherapy failed to provide long-term tumor control. Following incomplete surgical resection of atypical meningioma in elderly patients, adjuvant postoperative radiotherapy may not be an ideal treatment option, particularly when MIB-1 LI is higher than 19.7 %.

Outcome of resection of WHO Grade II meningioma and correlation of pathological and radiological predictive factors for recurrence

This study investigated whether extent of surgical resection (Simpson and Shinshu grade) along with pathological and radiological factors influence the tumor control and recurrence-free survival (RFS) of patients with World Health Organization (WHO) grade II meningiomas. The clinical, radiological and surgical notes on the 59 patients with WHO grade II meningioma managed at our institution over 20years were retrospectively reviewed. In this study, median survival time was 41months. The overall recurrence rate in Simpson grades I and II resection was 31%. In grades III and IV, the overall recurrence rate was 73%, and this high recurrence rate in these groups was confined within 5years. In Cox regression analysis, combined data of grades (I and II)/complete resection showed a significant difference in RFS compared to grades (III and IV)/subtotal resection (p=0.0001). A similar trend of RFS (p=0.0001) was observed with the Shinshu grading system of resection. In addition, a Ki-67% marker for proliferation less than 15% (p=0.029), absence of certain radiological features including heterogeneous enhancement, cyst formation and peritumoral edema (p=0.006), and repeat surgery for recurrent meningioma was associated with better survival (p=0.014). However, radiosurgery did not have a beneficial role in the treatment of recurrence of atypical meningioma. The Simpson grading system is the primary predictor of recurrence of WHO grade II meningioma after resection. In addition, certain pathological and radiological features need to be considered as possible factors of recurrence after resection. Lastly, depending on the likely risks and surgical morbidity, repeat surgical resection should be performed for recurrent atypical meningioma.

A case of an anaplastic meningioma metastasizing to the mediastinal lymph nodes

CONTEXT

Grade II and III (World Health Organization classification) meningiomas rarely develop in the spinal cord. However, we experienced a case with an anaplastic meningioma that developed in the spinal cord at the cervicothoracic junction and metastasized to the mediastinal lymph nodes. No such cases have previously been reported.

FINDINGS

The patient was a 68-year-old man who developed back pain that did not affect his daily living. He developed left lower limb paralysis, and was admitted after magnetic resonance imaging (MRI) revealed an intramedullary tumor at the level of cervical vertebra 7 and thoracic vertebra 1. Positron emission tomography revealed tracer uptake in the intramedullary tumor and the mediastinal lymph nodes, suggesting a metastatic spinal cord tumor or malignant lymphoma. A lymph node biopsy was then performed. Although the tumor was highly malignant, its primary site was not identified. Detailed examinations by several other departments revealed no abnormalities. On hospital day 30, his left lower limb paralysis deteriorated, and MRI revealed that the tumor had grown. Thus, laminaplasty, laminectomy, and tumor resection were performed. The tumor was an anaplastic meningioma that resembled mediastinal lymph node tissue, and other tumor lesions were not found. These findings suggested that an anaplastic meningioma had metastasized to the mediastinal lymph nodes. The patient did not respond to radiotherapy, and he was transferred to another hospital.

CONCLUSION

In cases of intramedullary spinal tumors with metastasis without other potential primary tumor lesions, early diagnosis and treatment should be performed while considering anaplastic meningioma.