Long-Term 25-Year Follow-up of Surgically Treated Parasagittal Meningiomas

Impact of Fractionation Regimen on Local Control Following Frameless Linear Accelerator-Based Image-Guided Stereotactic Radiosurgery and Radiotherapy for Intracranial Meningioma

OBJECTIVE

Stereotactic radiosurgery (SRS) is an established treatment for intracranial meningioma, yet this approach is often precluded by tumor size or proximity to critical structures. Fractionated radiotherapy (RT) may be employed to address these limitations. We performed a comparison of local control (LC) outcomes between 3 stereotactic techniques.

METHODS

A retrospective review was performed of 543 consecutive patients with 613 histologically-proven World Health Organization grade I or radiographically-defined benign intracranial meningioma treated with SRS (median dose: 1250 cGy) (n = 211), fractionated SRS (2500 cGy in 500 cGy fractions) (n = 170), or conventionally fractionated stereotactic radiotherapy (FSRT) (median dose: 5022 cGy in ≤200 cGy fractions) (n = 232) in the definitive (n = 475) or postoperative (n = 138) setting between January 2008 and December 2021. Postoperative treatment was delivered upfront after a subtotal resection (n = 43) or for recurrent disease (n = 95).

RESULTS

Median follow-up per lesion was 8.0 years. LC for all lesions at 5/10/14 years was 97.4%/86.8%/86.8%. Base of skull location (P = 0.01), tumor volume ≥5 cc (P = 0.01), and recurrent disease (P = 0.02) were associated with inferior LC. No difference was observed in LC by fractionation regimen; LC at 5/10 years was 97.3%/85.7% for SRS, 97.5%/89.1% for fractionated SRS, and 97.5%/86.3% for FSRT. Dose escalation above 1250 cGy for SRS or above 5040 cGy for FSRT did not result in improved LC.

CONCLUSIONS

Durable LC was observed at long-term follow-up of intracranial meningioma treated with stereotactic radiosurgery and RT. LC outcomes were similar across the 3 fractionation regimens, suggesting that clinicians may tailor RT recommendations based on clinical factors without concern for reduced efficacy.

Gene Expression Changes Associated With Recurrence After Gross Total Resection of Newly Diagnosed World Health Organization Grade 1 Meningioma

BACKGROUND AND OBJECTIVE

Patients who undergo gross total resection (GTR) of Central Nervous System World Health Organization (WHO) grade 1 meningioma constitute a "low-risk" group, but some low-risk meningiomas can recur despite reassuring clinical and histological features. In this study, gene expression values in newly diagnosed WHO grade 1 meningiomas that had undergone GTR were evaluated for their association with recurrence.

METHODS

This was a retrospective, international, multicenter cohort study that included WHO grade 1 meningiomas that underwent GTR, as first treatment, based on postoperative magnetic resonance imaging. Normalized gene expression values from a previously validated 34-gene panel were evaluated for their association with recurrence. Kaplan-Meier, multivariable Cox proportional hazard analyses, and K-means clustering were performed to assess the association of genes of interest with recurrence and identify molecular subgroups among clinically and histologically low-risk meningiomas.

RESULTS

In total, 442 patients with WHO grade 1 meningiomas that underwent GTR and had available gene expression profiling data were included in the study. The median follow-up was 5.0 years (interquartile range 2.6-7.7 years), local recurrence occurred in 36 patients (8.1%), 5-year local freedom from recurrence was 90.5%, and median time to recurrence was 2.9 years (range 0.5-10.7 years). Eleven genes were associated with local recurrence, including lower expression of ARID1B, ESR1, LINC02593, PGR, and TMEM30B and higher expression of CDK6, CDKN2C, CKS2, KIF20A, PGK1, and TAGLN. Of these genes, PGK1 had the largest effect size. K-means clustering based on these 11 genes distinguished 2 molecular groups of clinically and histologically low-risk meningiomas with significant differences in local freedom from recurrence (hazard ratio 2.5, 95% CI 1.2-5.1, P = .016).

CONCLUSION

Gene expression profiling may help to identify newly diagnosed WHO grade 1 meningiomas that have an elevated risk of recurrence despite GTR.

Parasagittal Meningiomas: The Impact of Sinus Opening and Grade of Resection on Clinical Outcome and Recurrence in a Consecutive Series of Patients

BACKGROUND

Surgical management of parasagittal meningiomas (PMs) remains controversial in the literature. The need to pursue a resection as radical as possible and the high risk of venous injuries contribute to making the sinus opening a widely argued choice. This study aimed to analyze factors affecting the risk of recurrence and to assess clinical outcomes of patients who underwent surgical resection of PMs with conservative or aggressive management of the intrasinusal portion.

METHODS

A single-institution retrospective review of all patients with PM surgically treated between January 2013 and March 2021 was conducted.

RESULTS

Among 56 patients, the sinus was opened in 32 patients (57%), and a conservative approach was used in 24 patients (43%). The sinus opening was found to be a predictive factor of radical resection (Simpson grade [SG] I-II) (P = 0.007). SG was the only predictive factor of recurrence (P < 0.001). The radical resection group (SG I-II) showed recurrence-free survival at 72 months of about 90% versus 30% in the non-radical resection group (SG III-IV) (log-rank test = 14.21, P < 0.001). Aggressive management of the sinus and radical resection were not found to be related to permanent deficit (P = 0.214 and P = 0.254) or worsening of Karnofsky performance scale score (P = 0.822 and P = 0.933).

CONCLUSIONS

Removal of the intrasinusal portion of the tumor using standard procedures is not associated with a higher risk of permanent deficit or worsening of Karnofsky performance scale and reduces the risk of recurrence.

The Evolving Classification of Meningiomas: Integration of Molecular Discoveries to Inform Patient Care

Meningioma classification and treatment have evolved over the past eight decades. Since Bailey, Cushing, and Eisenhart's description of meningiomas in the 1920s and 1930s, there have been continual advances in clinical stratification by histopathology, radiography and, most recently, molecular profiling, to improve prognostication and predict response to therapy. Precise and accurate classification is essential to optimizing management for patients with meningioma, which involves surveillance imaging, surgery, primary or adjuvant radiotherapy, and consideration for clinical trials. Currently, the World Health Organization (WHO) grade, extent of resection (EOR), and patient characteristics are used to guide management. While these have demonstrated reliability, a substantial number of seemingly benign lesions recur, suggesting opportunities for improvement of risk stratification. Furthermore, the role of adjuvant radiotherapy for grade 1 and 2 meningioma remains controversial. Over the last decade, numerous studies investigating the molecular drivers of clinical aggressiveness have been reported, with the identification of molecular markers that carry clinical implications as well as biomarkers of radiotherapy response. Here, we review the historical context of current practices, highlight recent molecular discoveries, and discuss the challenges of translating these findings into clinical practice.

Upfront stereotactic radiosurgery versus adjuvant radiosurgery for parasagittal and parafalcine meningiomas: a systematic review and meta-analysis

Parafalcine and parasagittal (PFPS) are common locations for meningiomas. Surgical resection for these tumors, the first-line treatment, poses challenges due to their proximity to critical structures. This systematic review investigates the use of stereotactic radiosurgery (SRS) as a treatment for PFPS meningiomas, aiming to elucidate its safety and efficacy. The review adhered to PRISMA guidelines. Searches were conducted on MEDLINE, Embase, and Cochrane. Inclusion criteria involved studies on SRS for PFPS meningiomas, reporting procedure outcomes and complications. Tumors were presumed or confirmed to be WHO grade 1. Data was systematically extracted. Meta-analysis was performed where applicable. The review included data from eight studies, 821 patients with 878 lesions. Tumor control was achieved in greater than 80% of cases. Adverse radiation effects were reported in 7.3% of them. Recurrence and further surgical approach were observed in 17.1% and 9.2% of cases, respectively. Symptom improvement was noted in 33.2% of patients. Edema occurred in approximately 25.1% of patients. A subgroup of 283 patients had upfront SRS, achieving tumor control in approximately 97% of such cases. SRS is a safe and effective treatment for PFPS meningiomas, both as an adjuvant therapy and as an upfront treatment for often smaller tumors. Post-SRS edema can typically be managed medically and usually does not require further surgical intervention. Further studies should provide more specific data on PFPS meningiomas. The use of single and hypofractionated SRS for larger volume PFPS meningiomas should be more explored to better define the risks and benefits.

Patterns of failure after radiosurgery for WHO grade 1 or imaging defined meningiomas: Long-term outcomes and implications for management

BACKGROUND

We analyzed long-term control and patterns of failure in patients with World Health Organization Grade 1 meningiomas treated with definitive or postoperative stereotactic radiosurgery at the authors' affiliated institution.

METHODS

96 patients were treated between 2004 and 2019 with definitive (n = 57) or postoperative (n = 39) stereotactic radiosurgery. Of the postoperative patients, 17 were treated adjuvantly following subtotal resection and 22 were treated as salvage at time of progression. Patients were treated to the gross tumor alone without margin or coverage of the dural tail to a median dose of 15 Gy. Median follow up was 7.4 years (inter-quartile range 4.8-11.3). Local control, marginal control, regional control, and progression-free survival were analyzed.

RESULTS

Local control at 5 and 10 years was 97 % and 95 %. PFS at 5 and 10 years was 94 % and 90 % with no failures reported after 6 years. Definitive and postoperative local control were similar at 5 (95 % [82-99 %] vs. 100 %) and 10 years (92 % [82-99 %] vs. 100 %). Patients treated with postoperative SRS did not have an increased marginal failure rate (p = 0.83) and only 2/39 (5 %) experienced recurrence elsewhere in the cavity.

CONCLUSIONS

Stereotactic radiosurgery targeting the gross tumor alone provides excellent local control and progression free survival in patients treated definitively and postoperatively. As in the definitive setting, patients treated postoperatively can be treated to gross tumor alone without need for additional margin or dural tail coverage.

Postoperative [68Ga]Ga-DOTA-TATE PET/CT imaging is prognostic for progression-free survival in meningioma WHO grade 1

PURPOSE

Tumor resection represents the first-line treatment for symptomatic meningiomas, and the extent of resection has been shown to be of prognostic importance. Assessment of tumor remnants with somatostatin receptor PET proves to be superior to intraoperative estimation with Simpson grading or MRI. In this preliminary study, we evaluate the prognostic relevance of postoperative PET for progression-free survival in meningiomas.

METHODS

We conducted a post hoc analysis on a prospective patient cohort with resected meningioma WHO grade 1. Patients received postoperative MRI and [68Ga]Ga-DOTA-TATE PET/CT and were followed regularly with MRI surveillance scans for detection of tumor recurrence/progression.

RESULTS

We included 46 patients with 49 tumors. The mean age at diagnosis was 57.8 ± 1.7 years with a male-to-female ratio of 1:1.7. Local tumor progression occurred in 7/49 patients (14%) after a median follow-up of 52 months. Positive PET was associated with an increased risk for progression (*p = 0.015) and a lower progression-free survival (*p = 0.029), whereas MRI was not. 20 out of 20 patients (100%) with negative PET findings remained recurrence-free. The location of recurrence/progression on MRI was adjacent to regions where postoperative PET indicated tumor remnants in all cases. Gross tumor volumes were higher on PET compared to MRI (*p = 0.032).

CONCLUSION

Our data show that [68Ga]Ga-DOTA-TATE PET/CT is highly sensitive in revealing tumor remnants in patients with meningioma WHO grade 1. Negative PET findings were associated with a higher progression-free survival, thus improving surveillance. In patients with tumor remnants, additional PET can optimize adjuvant radiotherapy target planning of surgically resected meningiomas.

Predictors of recurrence after surgical resection of parafalcine and parasagittal meningiomas

PURPOSE

Owing to their vicinity near the superior sagittal sinus, parasagittal and parafalcine meningiomas are challenging tumors to surgically resect. In this study, we investigate key factors that portend increased risk of recurrence after surgery.

METHODS

This is a retrospective study of patients who underwent resection of parasagittal and parafalcine meningiomas at our institution between 2012 and 2018. Relevant clinical, radiographic, and histopathological variables were selected for analysis as predictors of tumor recurrence.

RESULTS

A total of 110 consecutive subjects (mean age: 59.4 ± 15.2 years, 67.3% female) with 74 parasagittal and 36 parafalcine meningiomas (92 WHO grade 1, 18 WHO grade 2/3), are included in the study. A total of 37 patients (33.6%) exhibited recurrence with median follow-up of 42 months (IQR: 10-71). In the overall cohort, parasagittal meningiomas exhibited shorter progression-free survival compared to parafalcine meningiomas (Kaplan-Meier log-rank p = 0.045). On univariate analysis, predictors of recurrence include WHO grade 2/3 vs. grade 1 tumors (p < 0.001), higher Ki-67 indices (p < 0.001), partial (p = 0.04) or complete sinus invasion (p < 0.001), and subtotal resection (p < 0.001). Multivariable Cox regression analysis revealed high-grade meningiomas (HR: 3.62, 95% CI: 1.60-8.22; p = 0.002), complete sinus invasion (HR: 3.00, 95% CI: 1.16-7.79; p = 0.024), and subtotal resection (HR: 3.10, 95% CI: 1.38-6.96; p = 0.006) as independent factors that portend shorter time to recurrence.

CONCLUSION

This study identifies several pertinent factors that confer increased risk of recurrence after resection of parasagittal and parafalcine meningiomas, which can be used to devise appropriate surgical strategy to achieve improved patient outcomes.

Conditional Recurrence-Free Survival After Surgical Resection of Meningioma

BACKGROUND

Recurrence after meningioma resection warrants serial surveillance imaging, but little evidence guides the optimal time interval between imaging studies/surveillance duration.

OBJECTIVE

To describe recurrence-free survival (RFS) after meningioma resection, conditioned to short-term RFS.

METHODS

A retrospective cohort study for adults presenting for meningioma resection from 2000 to 2018 was conducted. The primary outcome was postoperative follow-up RFS. Conditional RFS Kaplan-Meier analysis was performed at 1, 2, 3, 5, and 10 years, conditioned to 6-month and 12-month RFS. RFS probabilities conditioned to 6-month RFS were estimated in subgroups, stratified by World Health Organization grade, extent of resection, and need for postoperative radiation.

RESULTS

In total, 723 patients were included. Median age at surgery was 57.4 years (IQR = 47.2-67.2). Median follow-up was 23.5 months (IQR = 12.3-47.8). Recurrence was observed in 90 patients (12%), with median time to recurrence of 14.4 months (IQR = 10.3-37.1). Conditioned to 6-month postoperative RFS, patients had 90.3% probability of remaining recurrence-free at 2 years and 69.4% at 10 years. Subgroup analysis conditioned to 6-month RFS demonstrated grade 1 meningiomas undergoing gross total resection (GTR) had 96.0% probability of RFS at 1 year and 82.8% at 5 years, whereas those undergoing non-GTR had 94.5% and 79.9% probability, respectively. RFS probability was 78.8% at 5 years for non-grade 1 meningiomas undergoing GTR, compared with 69.7% for non-grade 1 meningiomas undergoing non-GTR. Patients with non-grade 1 meningiomas undergoing upfront radiation had a 1-year RFS of 90.1% and 5-year RFS of 51.7%.

CONCLUSION

Recurrence risk after meningioma resection after an initial recurrence-free period is reported, with high-risk subgroups identified. These results can inform objective shared decision-making for optimal follow-up.

Impact of H3K27 trimethylation loss in meningiomas: a meta-analysis

Trimethylation of lysine 27 on histone 3 (H3K27me3) loss has been implicated in worse prognoses for patients with meningiomas. However, there have been challenges in measuring H3K27me3 loss, quantifying its impact, and interpreting its clinical utility. We conducted a systematic review across Pubmed, Embase, and Web of Science to identify studies examining H3K27me3 loss in meningioma. Clinical, histopathological, and immunohistochemistry (IHC) characteristics were aggregated. A meta-analysis was performed using a random-effects model to assess prevalence of H3K27me3 loss and meningioma recurrence risk. Study bias was characterized using the NIH Quality Assessment Tool and funnel plots. Nine publications met inclusion criteria with a total of 2376 meningioma cases. The prevalence of H3K27me3 loss was 16% (95% CI 0.09-0.27), with higher grade tumors associated with a significantly greater proportion of loss. H3K27me3 loss was more common in patients who were male, had recurrent meningiomas, or required adjuvant radiation therapy. Patients were 1.70 times more likely to have tumor recurrence with H3K27me3 loss (95% CI 1.35-2.15). The prevalence of H3K27me3 loss in WHO grade 2 and 3 meningiomas was found to be significantly greater in tissue samples less than five years old versus tissue of all ages and when a broader definition of IHC staining loss was applied. This analysis demonstrates that H3K27me3 loss significantly associates with more aggressive meningiomas. While differences in IHC and tumor tissue age have led to heterogeneity in studying H3K27me3 loss, a robust prognostic signal is present. Our findings suggest an opportunity to improve study design and standardize tissue processing to optimize clinical viability of this epigenetic marker.

Meningiomas with CNS invasion

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

Application of radiomics to meningiomas: A systematic review

BACKGROUND

Quantitative imaging analysis through radiomics is a powerful technology to non-invasively assess molecular correlates and guide clinical decision-making. There has been growing interest in image-based phenotyping for meningiomas given the complexities in management.

METHODS

We systematically reviewed meningioma radiomics analyses published in PubMed, Embase, and Web of Science until December 20, 2021. We compiled performance data and assessed publication quality using the radiomics quality score (RQS).

RESULTS

A total of 170 publications were grouped into 5 categories of radiomics applications to meningiomas: Tumor detection and segmentation (21%), classification across neurologic diseases (54%), grading (14%), feature correlation (3%), and prognostication (8%). A majority focused on technical model development (73%) versus clinical applications (27%), with increasing adoption of deep learning. Studies utilized either private institutional (50%) or public (49%) datasets, with only 68% using a validation dataset. For detection and segmentation, radiomic models had a mean accuracy of 93.1 ± 8.1% and a dice coefficient of 88.8 ± 7.9%. Meningioma classification had a mean accuracy of 95.2 ± 4.0%. Tumor grading had a mean area-under-the-curve (AUC) of 0.85 ± 0.08. Correlation with meningioma biological features had a mean AUC of 0.89 ± 0.07. Prognostication of the clinical course had a mean AUC of 0.83 ± 0.08. While clinical studies had a higher mean RQS compared to technical studies, quality was low overall with a mean RQS of 6.7 ± 5.9 (possible range -8 to 36).

CONCLUSIONS

There has been global growth in meningioma radiomics, driven by data accessibility and novel computational methodology. Translatability toward complex tasks such as prognostication requires studies that improve quality, develop comprehensive patient datasets, and engage in prospective trials.

Long-term postoperative health-related quality of life in patients with subfrontal meningiomas

OBJECTIVE

Subfrontal meningiomas grow insidiously in areas with high cerebral compliance and a relative scarcity of eloquent function. Symptoms develop progressively, are nonspecific, and include anosmia, changes in personality and cognition, depressive symptoms, headaches, visual disturbances, and seizures. Patients with subfrontal meningiomas carry the highest risk of developing psychological symptoms, which makes patient-reported outcome in terms of long-term health-related quality of life (HRQOL), anxiety, and depression of particular importance. This observational study aimed to investigate long-term HRQOL, anxiety, and depression in patients with subfrontal meningiomas who underwent a bifrontal craniotomy (subfrontal) approach between 2008 and 2017 at a single tertiary center. Correlations between preoperative, perioperative, and postoperative factors and HRQOL, anxiety, and depression were analyzed to detect prognostic factors.

METHODS

Seventy-seven consecutive patients who underwent operations at Rigshospitalet, Copenhagen, Denmark, between 2008 and 2017 were retrospectively analyzed. Patients were prospectively invited to respond to the Functional Assessment of Cancer Therapy-General, Functional Assessment of Cancer Therapy-Brain, and Hospital Anxiety and Depression Scale. Information regarding preoperative, perioperative, and postoperative factors were collected from the patients' medical records and scans.

RESULTS

Patients with subfrontal meningiomas exhibited better HRQOL and lower levels of anxiety and depression than general populations and other meningioma and glioblastoma cohorts. The only statistically significant prognostic factors for long-term HRQOL were number of symptoms at diagnosis and whether patients were discharged home or to a local hospital postoperatively. Tumor and peritumoral brain edema volumes were not prognostic factors.

CONCLUSIONS

Patients with subfrontal meningiomas exhibited better long-term postoperative HRQOL and were less likely to have anxiety or depression than the reference populations. This information on long-term prognosis is very valuable for patients, next of kin, and neurosurgeons and has not been previously studied in detail.

Radiotherapy and radiosurgery for meningiomas

Meningiomas comprise a histologically and clinically diverse set of tumors arising from the meningothelial lining of the central nervous system. In the past decade, remarkable progress has been made in deciphering the biology of these common neoplasms. Nevertheless, effective systemic or molecular therapies for meningiomas remain elusive and are active areas of preclinical and clinical investigation. Thus, standard treatment modalities for meningiomas are limited to maximal safe resection, radiotherapy, or radiosurgery. This review examines the history, clinical rationale, and future directions of radiotherapy and radiosurgery as integral and effective treatments for meningiomas.

Differences in intraoperative sampling during meningioma surgery regarding CNS invasion - Results of a survey on behalf of the EANS skull base section

Introduction

and Research Question: Invasive growth of meningiomas into CNS tissue is rare but of prognostic significance. While it has entered the WHO classification as a stand-alone criterion for atypia, its true prognostic impact remains controversial. Retrospective analyses, on which the current evidence is based, show conflicting results. Discordant findings might be explained by different intraoperative sampling methodologies.

Material and methods

To assess the applied sampling methods in the light of the novel prognostic impact of CNS invasion, an anonymous survey was designed and distributed via the EANS website and newsletter. The survey was open from June 5th until July 15th, 2022.

Results

After exclusion of 13 incomplete responses, 142 (91.6%) datasets were used for statistical analysis. Only 47.2% of participants' institutions utilize a standardized sampling method, and 54.9% pursue a complete sampling of the area of contact between the meningioma surface and CNS tissue. Most respondents (77.5%) did not change their sampling practice after introduction of the new grading criteria to the WHO classification of 2016. Intraoperative suspicion of CNS invasion changes the sampling for half of the participants (49.3%). Additional sampling of suspicious areas of interest is reported in 53.5%. Dural attachment and adjacent bone are more readily sampled separately if tumor invasion is suspected (72.5% and 74.6%, respectively), compared to meningioma tissue with signs of CNS invasion (59.9%).

Discussion and conclusions

Intraoperative sampling methods during meningioma resection vary among neurosurgical departments. There is need for a structured sampling to optimize the diagnostic yield of CNS invasion.

Volumetric Growth and Growth Curve Analysis of Residual Intracranial Meningioma

BACKGROUND

After meningioma surgery, approximately 1 in 3 patients will have residual tumor that requires ongoing imaging surveillance. The precise volumetric growth rates of these tumors are unknown.

OBJECTIVE

To identify the volumetric growth rates of residual meningioma, growth trajectory, and factors associated with progression.

METHODS

Patients with residual meningioma identified at a tertiary neurosurgery center between 2004 and 2020 were retrospectively reviewed. Tumor volume was measured using manual segmentation, after surgery and at every follow-up MRI scan. Growth rates were ascertained using a linear mixed-effects model and nonlinear regression analysis of growth trajectories. Progression was defined according to the Response Assessment in Neuro-Oncology (RANO) criteria (40% volume increase).

RESULTS

There were 236 patients with residual meningioma. One hundred and thirty-two patients (56.0%) progressed according to the RANO criteria, with 86 patients being conservatively managed (65.2%) after progression. Thirteen patients (5.5%) developed clinical progression. Over a median follow-up of 5.3 years (interquartile range, 3.5-8.6 years), the absolute growth rate was 0.11 cm 3 per year and the relative growth rate 4.3% per year. Factors associated with residual meningioma progression in multivariable Cox regression analysis were skull base location (hazard ratio [HR] 1.60, 95% CI 1.02-2.50) and increasing Ki-67 index (HR 3.43, 95% CI 1.19-9.90). Most meningioma exhibited exponential and logistic growth patterns (median R 2 value 0.84, 95% CI 0.60-0.90).

CONCLUSION

Absolute and relative growth rates of residual meningioma are low, but most meet the RANO criteria for progression. Location and Ki-67 index can be used to stratify adjuvant treatment and surveillance paradigms.

Long-term outcomes of fractionated proton beam therapy for benign or radiographic intracranial meningioma

PURPOSE

Benign intracranial meningioma is one of the most common primary brain neoplasms. Proton therapy has been increasingly utilized for nonoperative management of this neoplasm, yet few long-term outcomes studies exist.

METHODS

The medical records of a total of 59 patients with 64 lesions were reviewed under a prospective outcomes tracking protocol for histologically proven or radiographically benign meningioma. The patients were treated with proton therapy at the University of Florida Proton Therapy Institute between 2007 and 2019 and given a median dose of 50.4 GyRBE at 1.8 GyRBE (relative biological effectiveness) (range 48.6-61.2 GyRBE) in once-daily treatments.

RESULTS

With a median clinical and imaging follow-up of 6.3 and 4.7 years, the rates of 5-year actuarial local progression and cumulative incidence of grade 3 or greater toxicity were 6% (95% confidence interval [CI] 1%-14%), and 2% (95% CI < 1%-15%), respectively. Two patients experienced local progression after 5 years. The 5-year actuarial overall survival rate was 87% (95% CI 74-94%).

CONCLUSION

Fractionated PBT up to 50.4 GyRBE is a safe and highly effective therapy for treating benign intracranial meningioma.

Supervised machine learning algorithms demonstrate proliferation index correlates with long-term recurrence after complete resection of WHO grade I meningioma

OBJECTIVE

Meningiomas are the most common primary intracranial tumor, and resection is a mainstay of treatment. It is unclear what duration of imaging follow-up is reasonable for WHO grade I meningiomas undergoing complete resection. This study examined recurrence rates, timing of recurrence, and risk factors for recurrence in patients undergoing a complete resection (as defined by both postoperative MRI and intraoperative impression) of WHO grade I meningiomas.

METHODS

The authors conducted a retrospective, single-center study examining recurrence risk for adult patients with a single intracranial meningioma that underwent complete resection. Uni- and multivariate nominal logistic regression and Cox proportional hazards analyses were performed to identify variables associated with recurrence and time to recurrence. Two supervised machine learning algorithms were then implemented to confirm factors within the cohort that were associated with recurrence.

RESULTS

The cohort consisted of 823 patients who met inclusion criteria, and 56 patients (6.8%) had recurrence on imaging follow-up. The median age of the cohort was 56 years, and 77.4% of patients were female. The median duration of head imaging follow-up for the entire cohort was 2.7 years, but for the subgroup of patients who had a recurrence, the median follow-up was 10.1 years. Estimated 1-, 5-, 10-, and 15-year recurrence-free survival rates were 99.8% (95% confidence interval [CI] 98.8%-99.9%), 91.0% (95% CI 87.7%-93.6%), 83.6% (95% CI 78.6%-87.6%), and 77.3% (95% CI 69.7%-83.4%), respectively, for the entire cohort. On multivariate analysis, MIB-1 index (odds ratio [OR] per 1% increase: 1.34, 95% CI 1.13-1.58, p = 0.0003) and follow-up duration (OR per year: 1.12, 95% CI 1.03-1.21, p = 0.012) were both associated with recurrence. Gradient-boosted decision tree and random forest analyses both identified MIB-1 index as the main factor associated with recurrence, aside from length of imaging follow-up. For tumors with an MIB-1 index < 8, recurrences were documented up to 8 years after surgery. For tumors with an MIB-1 index ≥ 8, recurrences were documented up to 12 years following surgery.

CONCLUSIONS

Long-term imaging follow-up is important even after a complete resection of a meningioma. Higher MIB-1 labeling index is associated with greater risk of recurrence. Imaging screening for at least 8 years in patients with an MIB-1 index < 8 and at least 12 years for those with an MIB-1 index ≥ 8 may be needed to detect long-term recurrences.

Surgical outcomes and prognostic factors of parasagittal meningioma: a single-center experience 165 consecutive cases

PURPOSE

This study aimed to estimate the prognostic factors, long-term outcomes, and surgical strategies for parasagittal meningioma (PSM) and provide a better understanding of surgical experience.

MATERIALS AND METHODS

Patients (n = 1438) who underwent surgery for meningioma between January 2012 and January 2013 were enrolled in a database. We then identified 165 patients with PSM based on this database.

RESULTS

Of the 165 patients with identified PSMs, 103 were female and 62 were male, with a mean age of 49 years. Univariate analysis revealed that male sex (p = .002), non-World Health Organization (WHO) grade I meningioma (p < .001), treatment history (p = .006), surgical time more than 232 minutes (p = .006), and intraoperative bleeding > 300mL³ (p = .019) were associated with decreased progression-free survival (PFS). Multivariate analysis revealed that sex (hazards ratio [HR] = 3.836, 95% confidence interval [CI] = 1.364-10.794; p = .011], tumour grade (HR = 8.479, 95% CI = 3.234-22.230; p < .001), and surgical time (HR = 3.710, 95% CI = 1.057-13.023; p = .041) were independent factors for PFS. Patients with Simpson grade I-II (p = .015), no-treatment history (p = .006), tumour size < 3cm (p = .005), surgical time < 232 minutes (p = .019), intraoperative bleeding < 300mL³ (p < .001), or WHO grade I meningioma (p = .002) had better follow-up conditions.

CONCLUSION

Surgery was an effective treatment for PSM, and at the time of final follow-up, patients who received aggressive resection had a substantially higher Karnofsky performance scale score.

Granular clinical history and outcome in 51 patients with primary and secondary malignant meningioma

OBJECTIVE

WHO grade III meningiomas, also known as malignant meningiomas (MMs), are rare, and the heterogenous clinical course in patients with MM is not well described. To characterize the clinical course of patients with MM, granular clinical data were gathered from 51 patients treated at the Department of Neurosurgery and Radiation Oncology, Rigshospitalet, in Copenhagen, Denmark, between 2000 and 2020.

METHODS

The authors investigated outcome and timing in terms of 1) tumor progression and grade transformation in patients previously diagnosed with WHO grade I or II meningiomas (patients with a secondary MM [sMM]); 2) performance status and complications following surgery; and 3) transition to noncurative treatment and ultimately death. Complications, time between recurrences, and outcome (modified Rankin Scale [mRS] score) for every surgery were analyzed, both malignant and premalignant.

RESULTS

Of the 51 patients, 24 (47%) had an sMM. The time to WHO grade III transformation in the sMM group varied widely (median 5.5 years, range 0.5-22 years), but after transformation to a WHO grade III tumor, patients with an sMM and those with a primary MM (pMM) did not differ significantly in overall survival and cumulative risk of progression. Median overall survival for all 51 patients was 4.2 years (95% CI 2.6-7.2 years). Time from the decision to shift from curative to noncurative treatment until death was 3.8 months and the 30-day mortality rate following surgery was 11.8%. From a cumulative number of 151 surgeries, 10 surgeries were followed by improvement on the mRS, mRS score was unchanged in 70, and it worsened in 71. The MM was the underlying cause of death in 30 of 31 patients who had died at the end of follow-up.

CONCLUSIONS

Together, these findings clearly show a significant morbidity and mortality from the disease itself and from the treatment. These findings warrant studies of prognostic factors for earlier support and adjuvant measures in MM and identify a need for better palliative strategies in this patient group.

Long-Term Follow-Up, Treatment Strategies, Functional Outcome, and Health-Related Quality of Life after Surgery for WHO Grade 2 and 3 Intracranial Meningiomas

Simple Summary

Meningiomas are the most common group of primary intracranial tumors. While the majority are classified as WHO grade 1, WHO grade 2 and 3 meningiomas have poorer outcomes, even after gross total resection, and often require supplementary treatment. Long-term follow-up data regarding the progression-free survival (PFS) and overall survival (OS) for grade 2 and 3 tumors are scarce, and data evaluating the routine use of supplementary radiotherapy and radiosurgery have been inconclusive. Furthermore, few studies have reported data on the health-related quality of life (HRQoL), anxiety, and depression for these patients. In this population-based cohort study, we reviewed 51 cases of WHO grade 2 and 3 meningiomas. We found that the median OS was 13 years for grade 2 and 1.4 years for grade 3 meningiomas. Meningioma was the cause of death in 93% of the patients who passed away. The surviving patients showed HRQoL measures comparable to that of the general population, with the exception of significantly more anxiety and depression. All patients who worked preoperatively returned to work after their treatment.

Abstract

Progression-free survival (PFS) and overall survival (OS) for WHO grade 2 and 3 intracranial meningiomas are poorly described, and long-term results and data evaluating the routine use of supplementary fractionated radiotherapy (RT) or stereotactic radiosurgery (SRS) has been inconclusive. The aim of this study was to determine the long-term PFS and OS at a center that does not employ routine adjuvant RT. For this purpose, a retrospective population-based cohort study was conducted of all WHO grade 2 and 3 meningiomas surgically treated between 2005 and 2013. The cohort was uniformly defined according to the WHO 2007 criteria to allow comparisons to previously published reports. Patient records were reviewed, and patients were then prospectively contacted for structured quality-of-life assessments. In total, 51 consecutive patients were included, of whom 43 were WHO grade 2 and 8 were grade 3. A Simpson grade 1–2 resection was achieved in 62%. The median PFS was 31 months for grade 2 tumors, and 3.4 months for grade 3. The median OS was 13 years for grade 2, and 1.4 years for grade 3. The MIB-1-index was significantly associated with an increased risk for recurrence (p = 0.018, OR 1.12). The median PFS was significantly shorter for high-risk tumors compared to the low-risk group (10 vs. 46 months; p = 0.018). The surviving meningioma patients showed HRQoL measures comparable to that of the general population, with the exception of significantly more anxiety and depression. All patients who worked before surgery returned to work after their treatment. In conclusion, we confirm dismal prognoses in patients with grade 2 and 3 meningiomas, with tumor-related deaths resulting in severely reduced OS. However, the cohort was heterogenous, and a large subgroup of both grade 2 and 3 meningiomas was alive at 10 years follow-up, suggesting that a cure is possible. In addition, fractionated radiotherapy and chemotherapy had little benefit when introduced for recurrent and progressive diseases.

Predictive Power of MIB-1 vs. Mitotic Count on Progression-Free Survival in Skull-Base Meningioma

Simple Summary

Meningiomas are mainly benign intracranial tumors. Nevertheless, risk of recurrence exists in long-term follow-up, so new prognostic markers are still need to be identified. MIB-1 is no diagnostic criterion in WHO classification of meningiomas by now. This retrospective study shows that MIB-1 as well as mitotic count are good predictors for progression-free survival in skull-base meningiomas. The implantation of MIB-1 may enable an improved classification of meningiomas regarding progression-free survival. Moreover, this analysis of skull-base meningiomas shows that current cut-offs may have to be adjusted for meningioma location.

Abstract

Although meningiomas are mainly non-aggressive and slow-growing tumors, there is a remarkable recurrence rate in a long-term follow-up. Proliferative activity and progression-free survival (PFS) differs significantly among the anatomic location of meningiomas. The aim of the present study was to investigate the predictive power of MIB-1 labeling index and mitotic count (MC) regarding the probability of PFS in the subgroup of skull-base meningiomas. A total of 145 patients were included in this retrospective study. Histopathological examinations and follow-up data were collected. Ideal cut-off values for MIB-1 and MC were ≥4.75 and ≥6.5, respectively. MIB-1 as well as MC were good predictors for PFS in skull-base meningiomas. Time-dependent analysis of MIB-1 and MC in prediction of recurrence of skull-base meningioma showed that their prognostic values were comparable, but different cut-offs for MC should be considered regarding the meningioma’s location. As the achievement of a gross total resection can be more challenging in skull-base meningiomas and second surgery implies a higher risk profile, the recurrence risk could be stratified according to these findings and guide decision-making for follow-ups vs. adjuvant therapies.

What is the ideal grade of resection for parasagittal meningiomas with the invasion of superior sagittal sinus? Simpson I or Simpson II resection? A retrospective observational study

Background:

Parasagittal meningioma (PSM) is a tumor located in the parasagittal angle which extends to and/ or invades the superior sagittal sinus (SSS). Surgical resection of the PSM, the standard treatment in such cases, poses a challenge for neurosurgery, particularly where there is an invasion of the SSS. This is due to the risk of complications through injury to the adjacent vascular structures. The objective of the study was to perform a comparative evaluation of the surgical techniques for total resection of the PSM (Simpson Grade [SG] I and SG II), which present the highest rates of success in terms of the following variables: mortality, recurrence, and postoperative complications.

Methods:

Fifty-six patients undergoing resection surgery for PSM with the invasion of the SSS were enrolled. The patients were divided into two groups: Group A, comprising 26 cases of patients subjected to SG I PSM resection surgery and Group B, with 31 cases of patients subjected to SG II PSM resection surgery, with preservation of the SSS.

Results:

The results showed that Group B had lower rates of postoperative deficit (P = 0.026), zero mortality, and reduced recurrence. The use of complementary radiotherapy for atypical meningiomas (WHO II) in Group B was satisfactory in controlling the disease.

Conclusion:

The Simpson II, with preservation of the SSS, was better as it diminishes the vascular risks of surgery, reduces the frequency of severe postoperative deficit, and reduces mortality.

Management of Recurrent Meningiomas: State of the Art and Perspectives

Simple Summary

Intracranial meningiomas account for 30% to 40% of the primary lesions of the central nervous system. Surgery is the mainstay treatment whenever symptoms related to an intra-cranial meningioma are encountered. However, the management of recurrences after initial surgery, which are not uncommon, is still a matter of debate. Here, we present the alternatives described in the management of meningioma recurrence (radiotherapy, stereotaxic radiosurgery, protontherapy, and chemotherapy, among others). Their overall results are compared to surgery and future perspectives are presented.

Abstract

Background: While meningiomas often recur over time, the natural history of repeated recurrences and their management are not well described. Should recurrence occur, repeat surgery and/or use of adjuvant therapeutic options may be necessary. Here, we summarize current practice when it comes to meningioma recurrence after initial surgical management. Methods: A total of N = 89 articles were screened. N = 41 articles met the inclusion criteria and N = 16 articles failed to assess management of meningioma recurrence. Finally, N = 24 articles were included in our review. Results: The articles were distributed as follows: studies on chemotherapy (N = 14), radiotherapy, protontherapy, and stereotaxic radiosurgery (N = 6), boron-neutron capture therapy (N = 2) and surgery (N = 3). No study seems to provide serious alternatives to surgery in terms of progression-free and overall survival. Recurrence can occur long after the initial surgery and also affects WHO grade 1 meningiomas, even after initial gross total resection at first surgery, emphasizing the need for a long-term and comprehensive follow-up. Conclusions: Surgery still seems to be the state-of-the-art management when it comes to meningioma recurrence, since none of the non-surgical alternatives show promising results in terms of progression-free and overall survival.

The prognostic role of the immunohistochemical expression of S100 in meningiomas

BACKGROUND

Despite best clinical management, meningioma patients experience tumor recurrence. Efforts have been made to improve the prognostic stratification of meningiomas. Recently, a multi-faceted molecular classification suggested that the marker S100 is associated with a favorable outcome, making a further analysis in a larger cohort interesting.

MATERIALS AND METHODS

The immunohistochemical staining for S100 was analyzed in 1669 paraffin-embedded meningioma samples. The distribution and association with clinical data and progression-free survival via radiographic tumor recurrence were assessed.

RESULTS

Of 1669 cases, 218 tumors showed strong S100 expression (13.1%). A significantly higher frequency of S100 positive meningiomas was observed in meningiomas of female patients, tumors with spinal and convexity/falx location, primary tumor surgery, NF2, higher extent of resection, lower WHO CNS grade, adjuvant radiotherapy and recurrence-free tumors during follow-up. Univariate analysis revealed a favorable progression-free survival for meningiomas with S100 expression (p = 0.0059) but not in the multivariate analysis. Higher S100 frequency was independently associated with female gender (p = 0.0003), NF2 (p < 0.0001), tumor location (p < 0.0001) and lower WHO CNS grade (p = 0.0133).

CONCLUSIONS

The positive prognostic impact of S100 is mostly attributed to the confounding clinical factors gender, tumor location, NF2 status and WHO CNS grade.

Synthesizing Molecular and Immune Characteristics to Move Beyond WHO Grade in Meningiomas: A Focused Review

No portion of this manuscript has previously been presented. Meningiomas, the most common primary intracranial tumors, are histologically categorized by the World Health Organization (WHO) grading system. While higher WHO grade is generally associated with poor clinical outcomes, a significant subset of grade I tumors recur or progress, indicating a need for more reliable models of meningioma behavior. Several groups have developed risk scores based on molecular or immunologic characteristics. These classification schemes show promise, with several models preliminarily demonstrating similar or superior accuracy to WHO grading. Improved understanding of immune system recognition and targeting of meningioma subtypes is necessary to advance the predictive power, as well as develop new therapies. Here, we characterize meningioma molecular drivers, predictive of recurrence and progression, and describe specific aspects of the immune response to meningiomas while highlighting critical questions and ongoing research. Relevant manuscripts of interest were identified using a systematic approach and synthesized into this focused review. Finally, we summarize the ongoing and completed clinical trials for immunotherapy in meningiomas and offer perspective on future directions.

Inflammatory Tumor Microenvironment in Cranial Meningiomas: Clinical Implications and Intraindividual Reproducibility

The MIB-1 index was demonstrated to be significantly correlated to meningioma recurrence. However, to date, the relationship of the intraindividual course of the MIB-1 index and the growth fraction, respectively, to clinical tumor recurrence has not been demonstrated in cranial WHO grade 1 and 2 meningiomas. In the present paper, we compare the MIB-1 indices of 16 solely surgically treated primary meningiomas and their recurrent tumors regarding the course of the MIB-1 indices, time to recurrence, reproducibility and factors influencing the intraindividual MIB-1 indices. Regression analyses revealed (1) a strong intra-lab reproducibility (r = 0.88) of the MIB-1 index at the second versus the first operation, corresponding to a constant intrinsic growth activity of an individual meningioma, (2) a significant inverse correlation of both primary (r = −0.51) and secondary (r = −0.70) MIB-1 indices to time to recurrence, and (3) male sex, low plasma fibrinogen and diffuse CD68⁺ macrophage infiltrates contribute to an increase in the MIB-1 index. A strong intraindividual reproducibility of the MIB-1 index and a direct relationship of the MIB-1 index to the time to recurrence were observed. Individual MIB-1 indices might be used for tailored follow-up imaging intervals. Further research on the role of macrophages and inflammatory burden in the regrowth potential of meningiomas are needed.

Machine Learning for Prediction of Recurrence in Parasagittal and Parafalcine Meningiomas: Combined Clinical and MRI Texture Features

A subset of parasagittal and parafalcine (PSPF) meningiomas may show early progression/recurrence (P/R) after surgery. This study applied machine learning using combined clinical and texture features to predict P/R in PSPF meningiomas. A total of 57 consecutive patients with pathologically confirmed (WHO grade I) PSPF meningiomas treated in our institution between January 2007 to January 2019 were included. All included patients had complete preoperative magnetic resonance imaging (MRI) and more than one year MRI follow-up after surgery. Preoperative contrast-enhanced T1WI, T2WI, T1WI, and T2 fluid-attenuated inversion recovery (FLAIR) were analyzed retrospectively. The most significant 12 clinical features (extracted by LightGBM) and 73 texture features (extracted by SVM) were combined in random forest to predict P/R, and personalized radiomic scores were calculated. Thirteen patients (13/57, 22.8%) had P/R after surgery. The radiomic score was a high-risk factor for P/R with hazard ratio of 15.73 (p < 0.05) in multivariate hazards analysis. In receiver operating characteristic (ROC) analysis, an AUC of 0.91 with cut-off value of 0.269 was observed in radiomic scores for predicting P/R. Subtotal resection, low apparent diffusion coefficient (ADC) values, and high radiomic scores were associated with shorter progression-free survival (p < 0.05). Among different data input, machine learning using combined clinical and texture features showed the best predictive performance, with an accuracy of 91%, precision of 85%, and AUC of 0.88. Machine learning using combined clinical and texture features may have the potential to predict recurrence in PSPF meningiomas.

Identification and Management of Aggressive Meningiomas

Meningiomas are common primary central nervous system tumors derived from the meninges, with management most frequently entailing serial monitoring or a combination of surgery and/or radiation therapy. Although often considered benign lesions, meningiomas can not only be surgically inaccessible but also exhibit aggressive growth and recurrence. In such cases, adjuvant radiation and systemic therapy may be required for tumor control. In this review, we briefly describe the current WHO grading scale for meningioma and provide demonstrative cases of treatment-resistant meningiomas. We also summarize frequently observed molecular abnormalities and their correlation with intracranial location and recurrence rate. We then describe how genetic and epigenetic features might supplement or even replace histopathologic features for improved identification of aggressive lesions. Finally, we describe the role of surgery, radiotherapy, and ongoing systemic therapy as well as precision medicine clinical trials for the treatment of recurrent meningioma.

Transient Enlargement in Meningiomas Treated with Stereotactic Radiotherapy

Simple Summary

Accurate assessment of treatment efficacy is a prerequisite for the improvement in therapeutic outcomes in clinical trials. However, it is very challenging to accurately track the size of meningiomas after radiotherapy, because of their complex shapes and often slow growth. Measuring the whole tumor volume as opposed to simple diameter measurements to assess treatment efficacy, therefore, is very promising but little is known on expected volumetric changes of meningiomas following radiotherapy. Therefore, in this study, we meticulously investigated volumetric changes in meningiomas following radiotherapy incorporating volumetric measurements from 468 MRI studies and evaluated newly proposed RANO volumetric criteria in the context of radiotherapy. We found that temporary tumor enlargement after radiotherapy overall was rare but occurred significantly more frequently after high than after low single doses of radiation, represented an important differential diagnosis to tumor progression and would have skewed results in a clinical trial if not accounted for.

Abstract

To investigate the occurrence of pseudoprogression/transient enlargement in meningiomas after stereotactic radiotherapy (RT) and to evaluate recently proposed volumetric RANO meningioma criteria for response assessment in the context of RT. Sixty-nine meningiomas (benign: 90%, atypical: 10%) received stereotactic RT from January 2005–May 2018. A total of 468 MRI studies were segmented longitudinally during a median follow-up of 42.3 months. Best response and local control were evaluated according to recently proposed volumetric RANO criteria. Transient enlargement was defined as volumetric increase ≥20% followed by a subsequent regression ≥20%. The mean best volumetric response was −23% change from baseline (range, −86% to +19%). According to RANO, the best volumetric response was SD in 81% (56/69), MR in 13% (9/69) and PR in 6% (4/69). Transient enlargement occurred in only 6% (4/69) post RT but would have represented 60% (3/5) of cases with progressive disease if not accounted for. Transient enlargement was characterized by a mean maximum volumetric increase of +181% (range, +24% to +389 %) with all cases occurring in the first year post-RT (range, 4.1–10.3 months). Transient enlargement was significantly more frequent with SRS or hypofractionation than with conventional fractionation (25% vs. 2%, p = 0.015). Five-year volumetric control was 97.8% if transient enlargement was recognized but 92.9% if not accounted for. Transient enlargement/pseudoprogression in the first year following SRS and hypofractionated RT represents an important differential diagnosis, especially because of the high volumetric control achieved with stereotactic RT. Meningioma enlargement during subsequent post-RT follow-up and after conventional fractionation should raise suspicion for tumor progression.

Proposal of a new grading system for meningioma resection: the Copenhagen Protocol

INTRODUCTION

The extent of meningioma resection is the most fundamental risk factor for recurrence, and exact knowledge of extent of resection is necessary for prognostication and for planning of adjuvant treatment. Currently used classifications are the EANO-grading and the Simpson grading. The former comprises radiological imaging with contrast-enhanced MRI and differentiation between "gross total removal" and "subtotal removal," while the latter comprises a five-tiered differentiation of the surgeon's impression of the extent of resection. The extent of resection of tumors is usually defined via analyses of resection margins but has until now not been implemented for meningiomas. PET/MRI imaging with ⁶⁸Ga-DOTATOC allows more sensitive and specific imaging than MRI following surgery of meningiomas.

OBJECTIVE

To develop an objective grading system based on microscopic analyses of resection margins and sensitive radiological analyses to improve management of follow-up, adjuvant therapy, and prognostication of meningiomas. Based on the rationale of resection-margin analyses as gold standard and superior imaging performance of ⁶⁸Ga DOTATOC PET, we propose "Copenhagen Grading" for meningiomas.

RESULTS

Copenhagen Grading was described for six pilot patients with examples of positive and negative findings on histopathology and DOTATOC PET scanning. The grading could be traceably implemented and parameters of grading appeared complementary. Copenhagen Grading is prospectively implemented as a clinical standard at Rigshospitalet, Copenhagen.

CONCLUSION

Copenhagen Grading provided a comprehensive, logical, and reproducible definition of the extent of resection. It offers promise to be the most sensitive and specific imaging modality available for meningiomas. Clinical and cost-efficacy remain to be established during prospective implementation.

Health-Related Quality of Life and Return to Work after Surgery for Spinal Meningioma: A Population-Based Cohort Study

Simple Summary

Spinal meningioma is the most common primary intradural spinal tumor. Although histologically benign, the tumors often cause neurological deficits. Health-related quality of life (HRQoL) is defined as the aspects of quality of life which are most affected by ill health and is a measure of self-perceived health status. Despite many studies evaluating the neurological outcome after surgery for spinal meningiomas, no study has been concerned with the HRQoL and frequency of return to work. In this population-based cohort study, we reviewed 84 cases of surgically treated spinal meningiomas, with a mean follow-up of 8.7 years, to assess their HRQoL compared to a sample of the general population. We found that HRQoL after surgery was equal to the normal population, and the frequency of return to work was 100%, often within three months of surgery. Thus, surgical treatment of spinal meningiomas should not be considered a threat to long-term quality of life.

Abstract

Spinal meningiomas are the most common primary spinal intradural tumor. This study aimed to assess Health-related quality of life (HRQoL) and the frequency of return to work in patients surgically treated for spinal meningiomas, in comparison to the general population. Variables were collected from patient charts, EQ-5D-3L, and study specific questionnaires. Patients who had been operated between 2005–2017 were identified in a previous study and those alive in 2020 (104 of 129) were asked to participate. Eighty-four patients (80.8%) with a mean follow-up of 8.7 years, responded and were included. Data was compared to the Stockholm Public Health Survey 2006, a cross-sectional survey of a representative sample of the general population. Analysis for potential non-response bias showed no significant differences. Women in the meningioma sample scored more problems than men with regards to mobility (p = 0.048). There were no significant differences concerning EQ-5D_index (p = 0.325) or EQ_VAS (p = 0.116). The correlation between follow-up time and EQ-5D_index was low (r = 0.167). When comparing HRQoL to the general population sample, no significant differences were found within the EQ-5D-3L dimensions, EQ-5D_index or EQVAS. Those who postoperatively scored 3–5 on mMCs scored significantly more problems in the EQ-5D-3L dimension mobility (p = 0.023). Before surgery, 41 (48.8%) of the spinal meningioma patients were working and after surgery all returned to work, the majority within three months. Seventy-eight (96%) of the patients would accept surgery for the same diagnosis if asked today. We conclude that surgery for spinal meningiomas is associated with good long-term HRQoL and a high frequency of return to work.

Five-year cause-specific survival after meningioma surgery. A nationwide population-based study

BACKGROUND

Survival after meningioma surgery is often reported with inadequate allowance for competing causes of death.

METHODS

We processed the French administrative medical database (Système National des Données de Santé: SNDS), to retrieve appropriate cases of surgically treated meningioma. Cause-specific survival in meningioma-related death was analyzed with the Fine & Gray (F&G) and cause-specific (CS) Cox models to identify associated factors.

RESULTS

Five-year cumulative incidence was 2.85% for meningioma-related death and 6.3% for unrelated death (P<0.001). In the adjusted F&G and cause-specific Cox regression models for meningioma-related death, gender, age at surgery, co-morbidities, neurofibromatosis type 2, tumor insertion, tumor grade, cerebrospinal fluid (CSF) shunt insertion, preoperative embolization and need for redo surgery for recurrence emerged as independent prognostic factors of cause-specific survival (CSS) in meningioma-related death.

CONCLUSION

At 5 years, the risk of meningioma-unrelated death was 2.21-fold greater than the risk of dying from the meningioma disease. Five-year CSS after meningioma surgery was greater in younger adults with benign spinal meningioma with low comorbidity. Those with malignant cranial tumor requiring preoperative embolization or CSF shunting for associated hydrocephalus and with severely degraded overall health status showed a significantly increased risk of meningioma-related death. Redo surgery for recurrence failed to improve the risk of meningioma-related death. We recommend the use of net survival methods such as CSS in meningioma studies where unrelated mortality is predominant, as this approach results in more accurate estimates of disease risk and associated predictors.

Increased proliferation is associated with CNS invasion in meningiomas

INTRODUCTION

Meningiomas are the most common benign intracranial neoplasms. CNS invasion in meningiomas has been integrated into the 2016 WHO classification of CNS tumors as a stand-alone criterion for atypia. Since then, its prognostic impact has been debated based on contradictory results from retrospective analyses. The aim of the study was to elucidate whether histopathological evidence of CNS invasion is associated with increased proliferative potential.

METHODS

We have conducted a quantified measurement of the proliferation marker Ki67 and analyzed its association with CNS invasion determined by histology together with other established prognostic markers of progression. Routine, immunohistochemical staining for Ki67 were digitalized and automatic quantification was done using Image J software.

RESULTS

Overall, 1718 meningiomas were assessed. Histopathological CNS invasion was seen in 108 cases (6.7%). Uni- and multivariate analysis revealed a significantly higher Ki67 proliferation rate in meningiomas with CNS invasion (p < 0.0001 and p = 0.0098, respectively).

CONCLUSIONS

Meningiomas with histopathological CNS invasion show a higher proliferative activity.

The applicability of established clinical and histopathological risk factors for tumor recurrence during long-term postoperative care in meningioma patients

Risk factors to predict late-onset tumor recurrence in meningioma patients are urgently needed to schedule control intervals during long-term follow-up. We therefore analyzed the value of established risk factors for postoperative meningioma recurrence for the prediction of long-term prognosis. Correlations of clinical and histopathological variables with tumor relapse after 3, 5, and 10 years following microsurgery were analyzed in uni- and multivariate analyses, and compared to findings in the entire cohort. In the entire cohort (N = 1218), skull base location (HR: 1.51, 95%CI 1.05–2.16; p = .026), Simpson ≥ IV resections (HR: 2.41, 95%CI 1.52–3.84; p < .001), high-grade histology (HR: 3.70, 95%CI 2.50–5.47; p < .001), and male gender (HR: 1.46, 95%CI 1.01–2.11; p = .042) were independent risk factors for recurrence. Skull base location (HR: 1.92, 95%CI 1.17–3.17; p = .010 and HR: 2.02, 95%CI 1.04–3.95; p = .038) and high-grade histology (HR: 1.87, 95%CI 1.04–3.38; p = .038 and HR: 2.29, 95%CI 1.07–4.01; p = .034) but not subtotal resection (HR: 1.53, 95%CI .68–3.45; p = .303 and HR: 1.75, 95%CI .52–5.96; p = .369) remained correlated with recurrence after a recurrence-free follow-up of ≥ 3 and ≥ 5 years, respectively. Postoperative tumor volume was related with recurrence in general (p < .001) but not beyond a follow-up of ≥ 3 years (p > .05). In 147 patients with a follow-up of ≥ 10 years, ten recurrences occurred and were not correlated with any of the analyzed variables. Skull base tumor location and high-grade histology but not the extent of resection should be considered when scheduling the long-term follow-up after meningioma surgery. Recurrences ≥ 10 years after surgery are rare, and predictors are lacking.

Clinical Outcomes Following Re-Operations for Intracranial Meningioma

The outcomes following re-operation for meningioma are poorly described. The aim of this study was to identify risk factors for a performance status outcome following a second operation for a recurrent meningioma. A retrospective, comparative cohort study was conducted. The primary outcome measure was World Health Organization performance. Secondary outcomes were complications, and overall and progression free survival (OS and PFS respectively). Baseline clinical characteristics, tumor details, and operation details were collected. Multivariable binary logistic regression was used to identify risk factors for performance status outcome following a second operation. Between 1988 and 2018, 712 patients had surgery for intracranial meningiomas, 56 (7.9%) of which underwent a second operation for recurrence. Fifteen patients (26.8%) had worsened performance status after the second operation compared to three (5.4%) after the primary procedure (p = 0.002). An increased number of post-operative complications following the second operation was associated with a poorer performance status following that procedure (odds ratio 2.2 [95% CI 1.1-4.6]). The second operation complication rates were higher than after the first surgery (46.4%, n = 26 versus 32.1%, n = 18, p = 0.069). The median OS was 312.0 months (95% CI 257.8-366.2). The median PFS following the first operation was 35.0 months (95% CI 28.9-41.1). Following the second operation, the median PFS was 68.0 months (95% CI 49.1-86.9). The patients undergoing a second operation for meningioma had higher rates of post-operative complications, which is associated with poorer clinical outcomes. The decisions surrounding second operations must be balanced against the surgical risks and should take patient goals into consideration.

FORGE: A Novel Scoring System to Predict the MIB-1 Labeling Index in Intracranial Meningiomas

Simple Summary

Meningiomas are predominantly benign intracranial tumors, and surgical therapy represents the treatment of choice. However, the risk of recurrence and scheduling of follow-up intervals are significantly influenced by immunohistochemical items such as the MIB-1 labeling index. To date, it is not possible to integrate this essential information into the pre- or intraoperative surgical decision making. In the present study, we therefore analyzed baseline variables associated with the MIB-1 labeling index. We found four easily identifiable and routinely recorded risk factors for an increased MIB-1 index and developed a simple and quick-to-use score that allows us to estimate the risk of an elevated MIB-1 index prior to the surgical resection. Furthermore, this score seems to predict the progression-free survival in intracranial meningiomas. We believe that this score might us to more reliably guide patients in preoperative surgical strategy planning and postoperative follow-up scheduling.

Abstract

The MIB-1 index is an essential predictor of progression-free-survival (PFS) in meningioma. To date, the MIB-1 index is not available in preoperative treatment planning. A preoperative score estimating the MIB-1 index in patients with intracranial meningiomas has not been investigated so far. Between 2013 and 2019, 208 patients with tumor morphology data, MIB-1 index data, and plasma fibrinogen and serum C-reactive protein (CRP) data underwent surgery for intracranial WHO grade I and II meningioma. An optimal MIB-1 index cut-off value (≥6/<6) in the prediction of recurrence was determined by ROC curve analysis (AUC: 0.71; 95% CI: 0.55–0.87). A high MIB-1 index (≥6%) was present in 50 cases (24.0%) and was significantly associated with male sex, peritumoral edema, low baseline CRP, and low fibrinogen level in the multivariate analysis. A scoring system (“FORGE”) based on sex, peritumoral edema, preoperative CRP value, and plasma fibrinogen level supports prediction of the MIB-1 index (sensitivity 62%, specificity 79%). The MIB-1 labeling index and the FORGE score are significantly associated with an increased risk of poor PFS time. We suggest a novel score (“FORGE”) to preoperatively estimate the risk of an increased MIB-1 index (≥6%), which might help in surgical decision making and follow-up interval determination and inform future trials investigating inflammatory burden and proliferative activity.

Long-Term Follow-Up and Predictors of Functional Outcome after Surgery for Spinal Meningiomas: A Population-Based Cohort Study

Simple Summary

Spinal meningiomas are the most common adult primary intradural spinal tumors. While mostly benign, they may give rise to spinal cord compression with acute or chronic neurologic dysfunction. The primary treatment is surgical resection. Previous studies, limited by small sample sizes and short follow-up times, report that histopathological grade, tumor localization and size affect outcomes following surgery. In this population-based cohort study, we retrospectively reviewed 129 cases of surgically treated spinal meningiomas to assess postoperative complications, long-term clinical and radiological outcomes, predictors of neurological improvement and potential differences between elderly and non-elderly patients. Our median follow-up time was 8.2 years. We found that surgery was associated with significant neurological improvement. There was no significant difference in postoperative complications, tumor control or neurological improvement between elderly and non-elderly. Shorter time from diagnosis to surgery, larger tumor size and spinal cord compression predicted postoperative outcomes.

Abstract

Spinal meningiomas are the most common adult primary spinal tumor, constituting 24–45% of spinal intradural tumors and 2% of all meningiomas. The aim of this study was to assess postoperative complications, long-term outcomes, predictors of functional improvement and differences between elderly (≥70 years) and non-elderly (18–69 years) patients surgically treated for spinal meningiomas. Variables were retrospectively collected from patient charts and magnetic resonance images. Baseline comparisons, paired testing and regression analyses were used. In conclusion, 129 patients were included, with a median follow-up time of 8.2 years. Motor deficit was the most common presenting symptom (66%). The median time between diagnosis and surgery was 1.3 months. A postoperative complication occurred in 10 (7.8%) and tumor growth or recurrence in 6 (4.7%) patients. Surgery was associated with significant improvement of motor and sensory deficit, gait disturbance, bladder dysfunction and pain. Time to surgery, tumor area and the degree of spinal cord compression significantly predicted postoperative improvement in a modified McCormick scale (mMCs) in the univariable regression analysis, and spinal cord compression showed independent risk association in multivariable analysis. There was no difference in improvement, complications or tumor control between elderly and non-elderly patients. We concluded that surgery of spinal meningiomas was associated with significant long-term neurological improvement, which could be predicted by time to surgery, tumor size and spinal cord compression.

Risk of tumor recurrence in intracranial meningiomas: comparative analyses of the predictive value of the postoperative tumor volume and the Simpson classification

OBJECTIVE

In meningiomas, the Simpson grading system is applied to estimate the risk of postoperative recurrence, but might suffer from bias and limited overview of the resection cavity. In contrast, the value of the postoperative tumor volume as an objective predictor of recurrence is largely unexplored. The objective of this study was to compare the predictive value of residual tumor volume with the intraoperatively assessed extent of resection (EOR).

METHODS

The Simpson grade was determined in 939 patients after surgery for initially diagnosed intracranial meningioma. Tumor volume was measured on initial postoperative MRI within 6 months after surgery. Correlation between both variables and recurrence was compared using a tree-structured Cox regression model.

RESULTS

Recurrence correlated with Simpson grading (p = 0.003). In 423 patients (45%) with available imaging, residual tumor volume covered a broad range (0-78.5 cm3). MRI revealed tumor remnants in 8% after gross-total resection (Simpson grade I-III, range 0.12-33.5 cm3) with a Cohen's kappa coefficient of 0.7153. Postoperative tumor volume was correlated with recurrence in univariate analysis (HR 1.05 per cm3, 95% CI 1.02-1.08 per cm3, p < 0.001). A tree-structured Cox regression model revealed any postoperative tumor volume > 0 cm3 as a critical cutoff value for the prediction of relapse. Multivariate analysis confirmed the postoperative tumor volume (HR 1.05, p < 0.001) but not the Simpson grading (p = 0.398) as a predictor for recurrence.

CONCLUSIONS

EOR according to Simpson grading was overrated in 8% of tumors compared to postoperative imaging. Because the predictive value of postoperative imaging is superior to the Simpson grade, any residual tumor should be carefully considered during postoperative care of meningioma patients.

Long-term survival in patients with long-segment complex meningiomas occluding the dural venous sinuses: illustrative cases

BACKGROUND

Invasive sagittal sinus meningiomas are difficult tumors to cure by resection alone. Stereotactic radiosurgery (SRS) can be used as an adjuvant management strategy to improve tumor control after incomplete resection.

OBSERVATIONS

The authors reported the long-term retrospective follow-up of two patients whose recurrent parasagittal meningiomas eventually occluded their superior sagittal sinus. Both patients underwent staged radiosurgery and fractionated radiation therapy to achieve tumor control that extended to 20 years after their initial surgery. After initial subtotal resection of meningiomas that had invaded major cerebral venous sinuses, adjuvant radiosurgery was performed to enhance local tumor control. Over time, adjacent tumor progression required repeat SRS and fractionated radiation therapy to boost long-term tumor response. Staged multimodality intervention led to extended survival in these patients with otherwise unresectable meningiomas.

LESSONS

Multimodality management with radiosurgery and fractionated radiation therapy was associated with long-term survival of two patients with otherwise surgically incurable and invasive meningiomas of the dural venous sinuses.

Radiation-induced brain injury in patients with meningioma treated with proton or photon therapy

INTRODUCTION

Radiation therapy is often used to treat meningioma with adverse features or when unresectable. Proton therapy has advantages over photon therapy in reducing integral dose to the brain. This study compared the incidence of radiological and clinical adverse events after photon versus proton therapy in the treatment of meningioma.

METHODS

A retrospective review was conducted on patients with meningioma treated with proton or photon therapy at two high-volume tertiary cancer centers. Patients with a history of prior radiation therapy (RT) or less than 3 months of follow-up were excluded. Post-RT imaging changes were categorized into abnormal T2 signal intensities (T2 changes) or abnormal T1 post-contrast and T2 signal intensities (T1c+T2 changes) on magnetic resonance imaging (MRI). Clinical outcomes of adverse events and survival were compared between the proton and photon therapies.

RESULTS

Among the total of 77 patients, 38 patients received proton therapy and 39 patients received photon therapy. The median age at diagnosis was 55 years and median follow-up was 2.2 years. No significant differences in symptomatic adverse events were observed between the two groups: grade ≥ 2 adverse events were seen in 4 (10.5%) patients in the proton group and 3 (7.7%) patients in the photon group (p = 0.67). The 2-year cumulative incidences of T2 changes were 38.3% after proton therapy and 47.7% after photon therapy (p = 0.53) and the 2-year cumulative incidences of T1c+T2 changes were 26.8% after proton therapy and 5.3% after photon therapy (p = 0.02). One patient experienced grade ≥ 4 adverse event in each group (p = 0.99). Estimated 2-year progression-free survival was 79.5% (proton therapy 76.0% vs. photon therapy 81.3%, p = 0.66) and 2-year overall survival was 89.7% (proton therapy 86.6% vs. photon therapy 89.3%, p = 0.65).

CONCLUSIONS

Following RT, high rates of T2 changes were seen in meningioma patients regardless of treatment modality. Proton therapy was associated with significantly higher rates of T1c+T2 changes compared with photon therapy, but severe adverse events were uncommon in both groups and survival outcomes were comparable between the two groups. Future studies will aim at correlating the MRI changes with models that can be incorporated into RT planning to avoid toxicity.

Improved Detection of Postoperative Residual Meningioma with [68Ga]Ga-DOTA-TOC PET Imaging Using a High-resolution Research Tomograph PET Scanner

PURPOSE

PET with somatostatin receptor ligand [⁶⁸Ga]Ga-DOTA-D-Phe¹-Tyr³-octreotide ([⁶⁸Ga]Ga-DOTA-TOC) is an established method in radiotherapy planning because of the improved detection and delineation of meningioma tissue. We investigated the diagnostic accuracy of supplementary [⁶⁸Ga]Ga-DOTA-TOC PET in patients with a 3-month postoperative MRI reporting gross-total resection (GTR).

EXPERIMENTAL DESIGN

Thirty-seven patients with a histologically proven meningioma and GTR on postoperative MRI were prospectively referred to [⁶⁸Ga]Ga-DOTA-TOC PET. Detection and volume measurements of [⁶⁸Ga]Ga-DOTA-TOC-avid lesions in relation to the primary tumor site were recorded. Residual tumor in suspicious lesions suggested by [⁶⁸Ga]Ga-DOTA-TOC PET was verified by (i) tumor recurrence/progression on subsequent MRI scans according to the Response Assessment of Neuro-Oncology criteria, (ii) subsequent histology, and (iii) follow-up [⁶⁸Ga]Ga-DOTA-TOC PET scan.

RESULTS

Twenty-three PET scans demonstrated [⁶⁸Ga]Ga-DOTA-TOC-avid lesions suspicious of residual meningioma, where 18 could be verified by (i) tumor progression on subsequent MRI scans (n = 6), (ii) histologic confirmation (n = 3), and (iii) follow-up [⁶⁸Ga]Ga-DOTA-TOC PET scans confirming the initial PET findings (n = 9) after an overall median follow-up time of 17 months (range, 9-35 months). In contrast, disease recurrence was seen in only 2 of 14 patients without [⁶⁸Ga]Ga-DOTA-TOC-avid lesions (P < 0.0001). The sensitivity, specificity, and diagnostic accuracy of [⁶⁸Ga]Ga-DOTA-TOC PET in detecting meningioma residue was 90% [95% confidence interval (CI), 67-99], 92% (95% CI, 62-100), and 90% (95% CI, 74-98; P < 0.0001), respectively.

CONCLUSIONS

The majority of patients with GTR on 3-month postoperative MRI may have small unrecognized meningioma residues that can be detected using [⁶⁸Ga]Ga-DOTA-TOC PET.

Evaluation of Resection Margin after Image-Guided Dural Tail Resection in Convexity Meningiomas

Infiltration of adjacent dura with meningioma cells is a common phenomenon. Wide resection of the dural tail (DT) to achieve a gross total resection is a general recommendation. We aimed to investigate a tumor cell infiltration of the DT after image-guided resection of convexity meningiomas. The study’s inclusion criteria were the diagnosis of convexity meningioma, planned Simpson I° resection, and an identifiable DT. Intraoperative image-guidance was applied to identify the outer edge of the DT and to guide resection. After resection, en-bloc specimen or four samples of outermost pieces of DT in case of piecemeal resection were sent for histological analysis. In addition to resection margin infiltration, the radiological extent of DT, radiomic characteristics (109 in total), histology, and demographic data were assessed. Hierarchical clustering was used to generate patient clusters for radiomic analysis. Twenty-two patients were included in the study, while 20 (91%) were female. The mean age was 54.2 (Standard deviation (SD) 13.9, range 30–85) years. En-bloc resection could be achieved in 4 patients. The remaining patients received piecemeal resection. 2 DT samples were omitted due to tumor infiltration of the superior sagittal sinus. None of the en-bloc resection samples demonstrated dural infiltration on the resection margin. Tumor cells were detected in 4 of 70 (5.7%) dural tail samples and could not be excluded in another 5 of 70 (7.1%). No tumor recurrences were detected at follow-up MRI examinations after a mean follow-up of 27.5 (SD 13.2, range 0 to 50.0) months. There was no significant association between DT infiltration and histological subtype or patient characteristics and between DT extent and tumor infiltration. Clustering according to radiomic characteristics was not associated with tumor infiltration (p = 0.89). The radiological dural tail does not reliably outline the extent of tumor cell infiltration in convexity meningiomas. Hence, the extent of dural tail resection should not exclusively be guided by preoperative radiological appearance.

Hyperostosing sphenoid wing meningiomas: surgical outcomes and strategy for bone resection and multidisciplinary orbital reconstruction

OBJECTIVE

Hyperostosing sphenoid wing meningiomas cause bony hyperostosis that may extend into the orbit, resulting in proptosis, restriction of extraocular movements, and/or compressive optic neuropathy. The extent of bony removal necessary and the optimal reconstruction strategy to prevent enophthalmos is debated. Herein, the authors present their surgical outcomes and reconstruction results.

METHODS

This is a retrospective review of 54 consecutive patients undergoing resection of sphenoid wing meningiomas associated with bony hyperostosis. The majority of cases were operated on by the senior author. Extent of tumor resection, volumetric bone resection, radiographic exophthalmos index, complications, and recurrence were analyzed.

RESULTS

The median age of the cohort was 52.1 years, with women comprising 83% of patients. Proptosis was a presenting symptom in 74%, and 52% had decreased visual acuity. The WHO grade was I (85%) or II (15%). The median follow-up was 2.6 years. On volumetric analysis, a median 86% of hyperostotic bone was resected. Gross-total resection of the intracranial tumor was achieved in 43% and the orbital tumor in 27%, and of all intracranial and orbital components in 20%. Orbital reconstruction was performed in 96% of patients. Postoperative vision was stable or improved in 98% of patients and diplopia improved in 89%. Postoperative complications occurred in 44% of patients, and 26% of patients underwent additional surgery for complication management. The most frequent complications were medical complications and extraocular movement deficits. The median preoperative exophthalmos index was 1.26, which improved to 1.12 immediately postoperatively and to 1.09 at the 6-month follow-up (p < 0.001). Postoperatively, 18 patients (33%) underwent adjuvant radiotherapy after subtotal resection. Tumors recurred/progressed in 12 patients (22%).

CONCLUSIONS

Resection of hyperostosing sphenoid wing meningiomas, particularly achieving gross-total resection of hyperostotic bone with a good aesthetic result, is challenging and associated with notable medical and ocular morbidity. Recurrence rates in this series are higher than previously reported. Nevertheless, the authors were able to attain improvement in proptosis and visual symptoms in the majority of patients by using a multidisciplinary approach.

A nationwide population-based study on overall survival after meningioma surgery

BACKGROUND

There are very few nationwide studies on meningioma outcome, the most common primary intracranial tumour.

METHODS

We processed the French Système National des Données de Santé (SNDS) database using an algorithm combining the type of surgical procedure and the International Classification of Diseases to retrieve all cases of meningiomas operated between 2007 and 2017. A survival analysis was performed.

RESULTS

This nationwide study found 28 773 patients of which 75 % were female. Median age at surgery was 59 years, IQR[49-68]. Cranial convexity (24.4 %) and middle skull base (21.7 %) were the most common locations. 91.3 % of the tumours were benign and 2.6 % malignant.7.5 % of the patients underwent redo surgery, 9.1 % radiotherapy (RT) and 3.2 % stereotactic radiosurgery for recurrence. Median follow-up was 5.3 years 95 % CI [5.24-5.35]. 0.64 % of the patients died within a month of surgery and 2.1 % within a year. Overall survival (OS) rates at 5 and 10 years respectively were: 92.6 %, 95 %CI[92.3, 93] and 85 %, 95 %CI[84.3, 85.8]. In the multivariable analysis, female gender (HR = 0.64, 95 %CI[0.59, 0.69], p < 0.001), older age at surgery (HR= 1.07, 95 %CI[1.06, 1.07], p < 0.001), type 2 neurofibromatosis (HR= 3.89, 95 %CI[2.62, 5.76], p < 0.001), parasagittal (HR= 1.2, 95 %CI[1.05, 1.37], p = 0.00944) or falx cerebri location (HR= 1.18, 95 %CI[1.01, 1.37], p = 0.0343), atypical or (HR= 1.34, 95 %CI[1.15, 1.56], p < 0.001) malignant histology (HR= 2.34, 95 %CI[2.01, 2.73], p < 0.001), redo surgery (HR=1.81, 95 %CI[1.6, 2.04], p < 0.001), progressing meningioma (HR=1.34, 95 %CI[1.05, 1.71], p = 0.0175) or RT for recurrence (HR=2.17, 95 %CI[1.95, 2.4], p < 0.001) were established as independent prognostic factors of the OS.

CONCLUSION

In this registry-based study, OS after meningioma surgery is good and is even better in women, younger adults and those with convexity and benign tumour. We also found that NF2 patients and those required redo surgery or additional treatment for uncontrolled meningioma disease are further at risk of death.

Recurrence of surgically treated parasagittal meningiomas: a meta-analysis of risk factors

BACKGROUND

As the predictive role of many risk factors for parasagittal meningioma (PM) recurrence remains unclear, the objective of the meta-analysis was to make a comprehensive assessment of the predictive value of selected risk factors in these lesions.

METHODS

Studies including data on selected risk factors, such as histology, tumor and sinus resection, sinus invasion, tumor localization, and immediate postoperative radiotherapy for PMs recurrence, were searched in the NCBI/NLM PubMed/MEDLINE, EBM Reviews/Cochrane Central, ProQuest, and Scopus databases, and analyzed using random effects modeling.

RESULTS

Thirteen observational studies involving 1243 patients met the criteria for inclusion in the meta-analysis. WHO grading of meningiomas was identified as the most powerful risk factor for recurrence. WHO grade II meningiomas (OR 11.61; 95% CI 4.43-30.43; P < .01; I² = 31%) or composite group of WHO grades II and III (OR 14.84; 95% CI 5.10-43.19; P < .01; I² = 48%) had a significantly higher risk of recurrence than benign lesions. Moreover, an advanced sinus involvement (types IV-VI according to the Sindou classification) (OR 3.49; 95% CI 1.30-9.33; P = .01; I² = 0%) and partial tumor resection (Simpson grades III-V) (OR 2.73; 95% CI 1.41-5.30; P = .03; I² = 52%) were associated with a significantly higher risk of recurrence than their counterparts.

CONCLUSION

Among the selected risk factors, high-grade WHO lesions, advanced sinus invasion, and partial tumor resection were associated with a higher risk of PM recurrence, with WHO grading system being the most powerful risk factor.