Spinal meningioma and factors predictive of post-operative deterioration

Clinical, molecular, and genetic features of spinal meningiomas

Spinal meningiomas comprise 25%-46% of all primary spinal tumors. While the majority are benign and slow-growing, when left untreated, they can result in significant neurological decline. Emerging clinical, imaging, and molecular data have begun to reveal spinal meningiomas as distinct tumor subtypes compared to their intracranial counterparts. Moreover, recent studies indicate molecular and genetic subtype heterogeneity of spinal meningiomas both within and across the classically defined WHO grades. In the current review, we focus on recent advances highlighting the epidemiological, pathological, molecular/genetic, and clinical characteristics of spinal meningiomas. Furthermore, we explore patient and tumor-specific factors that predict prognosis and postoperative outcomes. We highlight areas that require further investigation, specifically efforts aimed at linking unique molecular, genetic, and imaging characteristics to distinct clinical presentations to better predict and manage patient outcomes.

Single-Center Experience of Resection of 120 Cases of Intradural Spinal Tumors

BACKGROUND

Our study presents a single-center experience of resection of intradural spinal tumors either with or without using intraoperative computed tomography-based registration and microscope-based augmented reality (AR). Microscope-based AR was recently described for improved orientation in the operative field in spine surgery, using superimposed images of segmented structures of interest in a two-dimensional or three-dimensional mode.

METHODS

All patients who underwent surgery for resection of intradural spinal tumors at our department were retrospectively included in the study. Clinical outcomes in terms of postoperative neurologic deficits and complications were evaluated, as well as neuroradiologic outcomes for tumor remnants and recurrence.

RESULTS

112 patients (57 female, 55 male; median age 55.8 ± 17.8 years) who underwent 120 surgeries for resection of intradural spinal tumors with the use of intraoperative neuromonitoring were included in the study, with a median follow-up of 39 ± 34.4 months. Nine patients died during the follow-up for reasons unrelated to surgery. The most common tumors were meningioma (n = 41), schwannoma (n = 37), myopapillary ependymomas (n = 12), ependymomas (n = 10), and others (20). Tumors were in the thoracic spine (n = 46), lumbar spine (n = 39), cervical spine (n = 32), lumbosacral spine (n = 1), thoracic and lumbar spine (n = 1), and 1 tumor in the cervical, thoracic, and lumbar spine. Four biopsies were performed, 10 partial resections, 13 subtotal resections, and 93 gross total resections. Laminectomy was the common approach. In 79 cases, patients experienced neurologic deficits before surgery, with ataxia and paraparesis as the most common ones. After surgery, 67 patients were unchanged, 49 improved and 4 worsened. Operative time, extent of resection, clinical outcome, and complication rate did not differ between the AR and non-AR groups. However, the use of AR improved orientation in the operative field by identification of important neurovascular structures.

CONCLUSIONS

High rates of gross total resection with favorable neurologic outcomes in most patients as well as low recurrence rates with comparable complication rates were noted in our single-center experience. AR improved intraoperative orientation and increased surgeons' comfort by enabling early identification of important anatomic structures; however, clinical and radiologic outcomes did not differ, when AR was not used.

Association of quantitative radiomic shape features with functional outcome after surgery for primary sporadic dorsal spinal meningiomas

Objective

Spinal meningiomas (SM) account for 25%-46% of all primary spinal tumors and show an excellent long-term disease control in case of complete resection. Therefore, the postoperative functional outcome is of high importance. To date, reports on dorsally located SM are scarce. Moreover, the impact of radiomics shape features on the functional outcome after surgery for primary dorsal SMs has not been analyzed yet.

Methods

We retrospectively performed an analysis of shape-based radiomic features in 3D slicer software and quantified the tumor volume, surface area, sphericity, surface area to volume ratio and tumor canal ratio. Subsequently, we evaluated the correlation between the radinomic parameters and the postoperative outcome according to Modified Japanese Orthopedic Association (mJOA) score.

Results

Between 2010 and 2022, we identified 24 Females and 2 Males operated on dorsal SMs in our institutional database. The most common SM localization was thoracic spine (n = 20), followed by cervical (n = 4), and lumbar (n = 2). The univariate analysis and the receiver operating characteristic (ROC) analysis showed a strong diagnostic performance of sphericity in the prediction of postoperative functional outcome based on mJOA score (AUC of 0.79, sphericity cut-of value 0.738; p = 0.01). Subsequently, the patients were divided into two groups (mJOA improved vs. mJOA stable/worsened). Patients with improved mJOA score showed significantly higher sphericity (0.79 ± 0.1 vs. 0.70 ± 1.0; p = 0.03). Finally, we divided the cohort based on sphericity (<0.738 and ≥0.738). The group with higher sphericity exhibited a significantly higher positive mJOA difference 3 months postoperatively (16.6 ± 1.4 vs. 14.8 ± 3.7; p = 0.03).

Conclusion

In our study investigating primary sporadic dorsal SMs, we demonstrated that a higher degree of sphericity may be a positive predictor of postoperative improvement, as indicated by the mJOA score.

Primary intradural extramedullary lesions: a longitudinal study of 212 patients and analysis of predictors of functional outcome

BACKGROUND

Primary intradural extramedullary (IDEM) lesions are rare, with an incidence of about 1/100,000 person-years. The aim of this study was to investigate their demographic, clinical, imaging, management, histopathological and outcome parameters. Another objective was to evaluate the various predicting factors leading to long-term favorable outcomes, thereby answering the controversial question: when to operate?

METHODS

This study observed 212 patients of primary IDEM lesions and followed-up for a mean of 53.80 months. The patient's outcome using McCormick grade at follow-up was correlated with age, sex, duration of symptoms, preoperative McCormick grade, tumor location and extent, extradural spread, extent of excision, vascularity, WHO grade and histopathological tumor type.

RESULTS

Benign nerve sheath tumors were the commonest lesions (47.17% schwannoma, 4.72% Neurofibroma), followed in incidence by meningioma (19.34%). There was predominance of males (57.08%), except in meningiomas (male: female ratio 1:2.15). Pain was the commonest initial symptom (51.88%). Limb weakness was the most common presenting complaint (88.68%). Gross total excision was achieved in 81.60% of cases and 70.75% of patients improved following surgery. The significant factors predicting favorable outcome included preoperative McCormick grade (P=0.001), the vertical extent of the tumor (P=0.027), histopathological tumor type (P=0.023) and WHO grading (P=0.015); and extent of excision had an odds ratio of 1: 2.5.

CONCLUSIONS

Significant predictors of functional outcome following surgery in IDEM lesions included preoperative McCormick grade, extent of the tumor, tumor type, WHO grading and extent of resection. The authors recommend surgery with the intent of complete tumor excision, before the onset of substantial symptoms, for better outcome.

Intradural extramedullary tumors. Retrospective cohort study assessing prognostic factors for functional outcome in adult patients

OBJECTIVE

The purpose of this study is to analyze a series of patients with intradural extramedullary tumors (IDEM) and assess factors that may modify or determine the final long term outcome and management.

MATERIALS AND METHODS

Single Center, retrospective study of a series of surgical patients with IDEM lesions from our Institution operated between 2010 and 2021. Patients with less than 6 months of follow up were excluded. Several preoperative demographics, clinical, imaging and surgical features, as well as histopathology, recurrence and adjuvancy were assessed. Patients' final clinical outcome was categorized using the McCormick scale.

RESULTS

A total of 203 patients with a mean follow-up of 30.50 months (range 6-130) were included. 57.64% of the analyzed population was female and the mean age was 50.51 years. The most frequent location of the tumors was dorsal (34.98%) followed by the lumbar region (32.02%). Total resection was achieved in 84.24% of cases, and the most frequent histopathology was Schwannoma (36.45%), followed by Meningioma (30.05%). Pain was the most usual initial symptom (63.05%). In our analysis, functional outcome after surgery was associated with statistical significance with preoperative McCormick grade, tumor type, EOR and postoperative complications such as hematoma and sphincter involvement.

CONCLUSION

The management of these lesions depends on many factors. It is worthy of mention that clinical presentation, EOR, histopathology and postoperative complications have shown significant prognostic value for the final outcome. Early treatment with the intention of achieving GTR when possible, using carefully tailored approaches, should be considered before the onset of significant symptoms.

Current Knowledge on Spinal Meningiomas-Surgical Treatment, Complications, and Outcomes: A Systematic Review and Meta-Analysis (Part 2)

Background: Most of the knowledge on spinal meningiomas is extrapolated from their intracranial counterparts, even though they are considered separate entities. This review aimed to systematically summarize studies covering different aspects of spinal meningiomas and their management. Methods: Databases were searched for all studies concerning spinal meningiomas dating from 2000 and onwards. When possible, a meta-analysis was performed. Results: Neurological outcomes of surgery were consistently favorable across studies, with a complication rate of 7.9% and 78.9% of the patients demonstrating good postoperative neurological function (McCormick score 1−2). The most relevant predictors of unfavorable outcomes were poor preoperative status, longer time from diagnosis to surgery, and surgery of recurrent tumors. The recurrence rate after surgery was estimated at 6%. Meta-analysis and/or survival analysis revealed that higher WHO grade (p < 0.001), higher Simpson grade (p < 0.001), ventral tumor location (p = 0.02), and male sex (p = 0.014) were all associated with higher odds of recurrence. However, the meta-analysis did not show any difference between Simpson grade 1 and grade 2 with respect to the odds of recurrence (p = 0.94). Surgery provided immediate and durable health-related quality-of-life improvement, as well as a high frequency of return to work. Conclusion: Spinal meningioma surgery is a relatively safe procedure with a low risk of tumor recurrence and high likelihood of favorable postoperative outcomes.

Unsuccessful external validation of the MAC-score for predicting increased MIB-1 index in patients with spinal meningiomas

OBJECTIVE

Recently, the MAC-spinal meningioma score (MAC-score) was proposed to preoperatively identify spinal meningioma patients with high MIB-1 indices. Risk factors were age ≥ 65 years, a modified McCormick score (mMCs) ≥ 2, and absence of tumor calcification. The aim of this study was to externally validate the MAC-score in an independent cohort.

METHODS

Using the same inclusion and exclusion criteria as in the original study, we performed a retrospective, single-center, population-based, cohort study that included patients who had undergone surgical treatment for spinal meningiomas between 2005 - 2017. Data was collected from patient charts and radiographic images. Validation was performed by applying the MAC-score to our cohort and evaluating the area under the receiver operating characteristic curve (AUC).

RESULTS

In total, 108 patients were included. Baseline and outcome data were comparable to the original development study. An increased MIB-1 index (≥5%) was observed in 56 (52%) patients. AUC of the MAC-score in our validation cohort was 0.61 (95% CI: 0.51 - 0.71), which corresponds to a poor discriminative ability.

CONCLUSION

The MAC-score showed poor discriminative ability for MIB-1 index prediction in patients with spinal meningiomas. Moreover, the MAC-score rests on a weak theoretical and statistical foundation. Consequently, we argue against its clinical implementation.

Characteristics of Patients Selected for Surgical Treatment of Spinal Meningioma

BACKGROUND

Spinal meningiomas are benign extra-axial tumors that can present with neurological deficits. Treatment partly depends on the degree of disability as there is no agreed-upon patient selection algorithm at present. We aimed to elucidate general patient selection patterns in patients undergoing surgery for spinal meningioma.

METHODS

Data for patients with spinal tumors admitted between 2016 and 2019 were extracted from the U.S. Nationwide Inpatient Sample. We identified patients with a primary diagnosis of spinal meningioma (using International Classification of Disease, 10^th revision codes) and divided them into surgical and nonsurgical treatment groups. Patient characteristics were evaluated for intergroup differences.

RESULTS

Of 6395 patients with spinal meningioma, 5845 (91.4%) underwent surgery. Advanced age, nonwhite race, obesity, diabetes mellitus, chronic renal failure, and anticoagulant/antiplatelet use were less prevalent in the surgical group (all P < 0.001). The only positive predictor of surgical treatment was elective admission status (odds ratio, 3.166; P < 0.001); negative predictors were low income, Medicaid insurance, anxiety, obesity, and plegia. Patients with bowel-bladder dysfunction, plegia, or radiculopathy were less likely to undergo surgical treatment. The surgery group was less likely to experience certain complications (deep vein thrombosis, P < 0.001; pulmonary embolism, P = 0.002). Increased total hospital charges were associated with nonwhite race, diabetes, depression, obesity, myelopathy, plegia, and surgery.

CONCLUSIONS

Patients treated surgically had a decreased incidence of complications, comorbidities, and Medicaid payer status. A pattern of increased utilization of health care resources and spending was also observed in the surgery group. The results indicate a potentially underserved population of patients with spinal meningioma.

Current knowledge on spinal meningiomas: a systematic review protocol

INTRODUCTION

Meningiomas are primary central nervous system tumours that arise from both cranial and spinal meninges. Spinal meningiomas occur less frequently than their cranial counterparts and are consequently given less attention in the literature. Therefore, systematic studies are needed to summarise the current knowledge on spinal meningiomas, providing a solid evidence base for treatment strategies. This systematic review of the literature will therefore assess studies describing spinal meningiomas, their epidemiology, diagnostics, treatment and outcomes.

METHODS AND ANALYSIS

Electronic databases, including PubMed, Web of Science and Embase, will be searched using the keywords "spinal" and "meningioma". The search will be set to provide only English studies published after 2000 to avoid any conflicts regarding terminology and classification, as well as to reflect the current status. Case reports, editorials, letters and reviews will also be excluded. Reference lists of relevant records will also be searched. Identified studies will be screened for inclusion, by one reviewer in a first step and then three in the next step to decrease the risk of bias. The results will be categorised to allow for a structured summary of the outcomes and their evidence grade conforming to the Grading of Recommendations, Assessment, Development and Evaluation approach. Categories may include: epidemiology, histopathology, radiological diagnostics, surgery, complications, non-surgical or adjuvant treatments, disease outcomes and predictors, and lastly recurrence. This review will summarise the current knowledge on spinal meningiomas to allow for a better understanding of the disease and contribute to improve its management. For clinicians, the systematic collection and grading of available evidence may aid in decision making and for those seeking to further the scientific field, this review may help to identify areas where knowledge is currently lacking.

ETHICS AND DISSEMINATION

Ethics approval was not required for our systematic review as it is based on existing publications. The results will be disseminated via submission for publication in a peer-reviewed journal.

Surgical Resection of Dorsal Spinal Meningiomas with the Inner Dura Layer - an Improved Preservation Technique of Spinal Dura in 40 Cases

BACKGROUND

Spinal meningiomas are the common benign tumors in intradural extramedullary spinal tumors. Simpson grade I resection is recommended to avoid tumor recurrence. However, the dura reconstruction increases a risk of cerebrospinal fluid leakage after this surgical resection. To address this concern, the inner dura layer resection and the long-term surgical outcomes of this technique were designed and examined after total tumor resection to preserve the outer dura layer.

METHODS

This study included 40 spinal meningioma patients undergoing the outer dura layer resection between 2002 and 2019. Clinical characteristics, radiological features, pre- and post-operative functional states, tumor recurrence and perioperative complications were described and evaluated.

RESULTS

A total of 40 spinal meningioma cases with the median age of 63 years (36-81 years) are enrolled in this study. The median postoperative follow-up period of all 40 cases is 96 months (34-193 months). About 82.5% of cases are located in the thoracic spine, while 16.5% of cases are located in the cervical spine. Of the symptomatic cases, 87.5% of cases follow with satisfactory outcomes, 12.5% of cases follow with unexpected outcomes. The local spinal meningioma recurrence rate was 2.5% (1 of 40 cases). None postoperative cerebrospinal fluid leak occurs in all 40 spinal meningioma cases.

CONCLUSION

A long-term of postoperative follow-up indicated this modified spinal dura preservation technique causes the good neurological improvement with rare recurrence. Therefore, we recommend this improved technique may be an alternative surgical option for total resection of spinal meningiomas with favorable prognosis.

Spinal cord compression in relation to clinical symptoms in patients with spinal meningiomas

OBJECTIVE

Spinal meningiomas are common primary tumors of the spinal canal and the resulting spinal cord compression (SCC) is intrinsically related to symptoms and outcome, but literature concerning this association is limited. We aimed to present data on both degree of SCC and tumor occupancy percentage in relation to neurological symptoms and outcome.

METHODS

Patients ≥ 18 years with a histological diagnosis of spinal canal meningioma treated between 2000 and 2017 were retrospectively evaluated for symptoms and neurological outcome in relation to SCC (i.e. compression of spinal cord at maximal tumor compression compared to maximum area above/below compression) and tumor occupancy percentage (percentage of dural sac area occupied by tumor at maximal tumor compression). Area segmentation of spinal cord, tumor and dural sac (as marker of spinal canal) was performed manually on magnetic resonance imaging (MRI) scans. The neurological deficit was assessed pre- and postoperatively according to the McCormick score. A logistic regression was made with a training set to identify the cut-off level for motor deficit.

RESULTS

The cohort included 111 patients with a mean age of 62.5 years and 77.5% were female. The dominating symptoms preoperatively were sensory disturbance (91.0%), motor deficit (80.2%) and gait disturbance (67.6%). Postoperatively 53.2% of patients, also in some of those with severe deficit and high tumor occupancy, improved their neurological deficit and 43.2% were unchanged. Patients with intradural meningioma and assessable MRI scans were included to evaluate SCC (n = 83). The mean extent of SCC was 50.6%. Exploration of tumor occupancy percentage identified a cut-off at 65% tumor occupancy to best discriminate between patients with or without motor deficit.

CONCLUSION

Patients with an intradural tumor occupancy percentage of > 65% are more likely to have a preoperative symptom and deficit, validating previous findings. Therefore, we suggest that even in asymptomatic, otherwise fit, patients with tumor occupancy approaching 65% should be considered for surgery since there is a high risk of developing deficit with even minimal growth. Concerning recovery, patients with tumor both high tumor occupancy and significantly impaired function tended to improve their functional level postoperatively.

Spinal Meningiomas: Influence of Cord Compression and Radiological Features on Preoperative Functional Status and Outcome

Simple Summary

Patients affected by spinal meningioma globally exhibit an excellent postoperative functional outcome despite tumor size and severity of spinal cord compression. This work aims to analyze the impact of tumor size and other radiological findings on clinical functional preoperative status and postoperative outcome. In this multicentric retrospective study involving 90 adult patients, we found that spinal cord and tumor occupancy as well as cord compression and tumor volume are correlated with low preoperative functional status. Higher tumor occupancy and tumor-canal volume ratio corresponded to lower postoperative neurological recovery. Cord re-expansion did not show any correlation with postoperative outcome, while preoperative signs of cord myelopathy were predictors of worse postoperative outcome. These findings suggest that these radiological features should be taken into consideration during preoperative counselling.

Abstract

Background: Radiological parameters predicting the postoperative neurological outcome after resection of a spinal meningioma (SM) are poorly studied, with controversial results. Methods: Observational multicenter cohort (2011–2018) of adult patients undergoing surgery for resection of SM. Tumor-canal volume ratio (TCR), the areas related to the cord and tumor occupancy at maximum compression, the presence of dural tail, calcifications, signs of myelopathy, and postoperative cord expansion were compared with the modified McCormick scale (mMCS) preoperative and at follow-up. Results: In the cohort (n = 90 patients), cord and tumor occupancy as well as cord compression and tumor volume showed a correlation with preoperative mMCS (p < 0.05, R −0.23; p < 0.001, R 0.35; p < 0.005, R −0.29; p < 0.001, R 0.42). Cord occupancy had a strong correlation with cord compression (p < 0.001, R 0.72). Tumor occupancy and TCR were correlated with relative outcome at follow-up (p < 0.005 R 0.3; p < 0.005 R 0.29). No correlation was found between cord re-expansion and clinical outcome at follow-up. Finally, a correlation was shown between preoperative signs of cord myelopathy and mMCS (p < 0.05 R 0.21) at follow-up. Conclusions: Larger tumors showed lower preoperative functional status and a worse clinical outcome. Moreover, preoperative T2 cord signal changes are correlated with a poorer outcome.

Age at Diagnosis and Baseline Myelomalacia Sign Predict Functional Outcome After Spinal Meningioma Surgery

Objective: Spinal meningioma (SM) accounts for 12% of all meningiomas. Clinical and immunohistochemical factors were analyzed with regard to functional outcome, surgical adverse events, and tumor recurrence.

Methods: One-hundred and twenty-three consecutive SM patients underwent surgery and were retrospectively reviewed with regard to demographic parameters, imaging features, neurological function, and immunohistochemical items. Neurological function was graded according to the Modified McCormick Scale (MMS) and dichotomized as “good (grade I + II)” and “poor (grade III–V)” function.

Results: One-hundred and fourteen (92.7%) WHO grade I and 9 (7.3%) WHO grade II SM were included in this study. Univariate analysis identified a baseline T2 hyperintensity of the spinal cord, baseline symptom duration ≥4 weeks, age ≥66 years, and dural tail sign as predictors of poor MMS. Baseline T2 hyperintensity of the spinal cord [Odds ratio (OR) = 13.3, 95% CI = 3.4–52.1, p < 0.001] and age ≥66 years (OR = 10.3, 95% CI = 2.6–41.1, p = 0.001) were independent predictors of a poor MMS grade at discharge after SM surgery in the multivariate binary logistic regression analysis. The 12- and 24-month recurrence-free survival rates were 98.7 % (1/80) and 94.7% (2/38), respectively. In those patients with tumor recurrence of the SM, highly increased MIB-1 (≥5%) labeling indices were observed.

Conclusion: Baseline T2 hyperintensity, especially in the elderly patients, is a strong predictor of poorer recovery after spinal meningioma surgery. SMs with high proliferative activity should be followed-up closely despite maximal safe resection.

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.

Correlations between preoperative clinical factors and treatment outcome of spinal meningiomas - A retrospective study of a series of 31 cases

Background:

The purpose of the current study is to identify the correlations between the most important preoperative clinical factors and the outcome of surgery of spinal meningiomas (SM).

Methods:

We performed a retrospective analysis of the medical history, clinical, paraclinical, neuroimaging, and surgical protocol data in 31 patients with SM who underwent surgical resection at our institution from January 2011 to July 2020. The degree of resection was assessed on the Simpson scale. The modified McCormick scale was used to monitor the effect and outcome of treatment at admission, discharge, and at further follow-up.

Results:

The average age of the patients was 65 years (37-78). Vertebral pain and motor deficits were the most common initial symptoms that occurred in 26 (89.6%) and 29 (93.5%) patients, respectively. Sphincter disorders were found in 9 (29%) patients. Total resection (Simpson Grade I – II) was achieved in 29 patients (93.5%). We achieved a favorable outcome (McCormick Gr. I to III) in 93.3% of patients. The degree of the neurological deficit (P = 0.026) and the presence of sphincter disorders (P = 0.009) were the preoperative clinical factors that most significantly correlated with the outcome of treatment.

Conclusion:

The outcome from the surgical treatment of SM correlated significantly with the degree of the preoperative neurological deficit. Therefore, patients presenting with more severe symptoms are expected to have worse outcomes.

Efficacy of Transcranial Motor Evoked Potential Monitoring During Intra- and Extramedullary Spinal Cord Tumor Surgery: A Prospective Multicenter Study of the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

STUDY DESIGN

Multicenter prospective study.

OBJECTIVES

Although intramedullary spinal cord tumor (IMSCT) and extramedullary SCT (EMSCT) surgeries carry high risk of intraoperative motor deficits (MDs), the benefits of transcranial motor evoked potential (TcMEP) monitoring are well-accepted; however, comparisons have not yet been conducted. This study aimed to clarify the efficacy of TcMEP monitoring during IMSCT and EMSCT resection surgeries.

METHODS

We prospectively reviewed TcMEP monitoring data of 81 consecutive IMSCT and 347 EMSCT patients. We compared the efficacy of interventions based on TcMEP alerts in the IMSCT and EMSCT groups. We defined our alert point as a TcMEP amplitude reduction of ≥70% from baseline.

RESULTS

In the IMSCT group, TcMEP monitoring revealed 20 true-positive (25%), 8 rescue (10%; rescue rate 29%), 10 false-positive, a false-negative, and 41 true-negative patients, resulting in a sensitivity of 95% and a specificity of 80%. In the EMSCT group, TcMEP monitoring revealed 20 true-positive (6%), 24 rescue (7%; rescue rate 55%), 29 false-positive, 2 false-negative, and 263 true-negative patients, resulting in a sensitivity of 91% and specificity of 90%. The most common TcMEP alert timing was during tumor resection (96% vs. 91%), and suspension surgeries with or without intravenous steroid administration were performed as intervention techniques.

CONCLUSIONS

Postoperative MD rates in IMSCT and EMSCT surgeries using TcMEP monitoring were 25% and 6%, and rescue rates were 29% and 55%. We believe that the usage of TcMEP monitoring and appropriate intervention techniques during SCT surgeries might have predicted and prevented the occurrence of intraoperative MDs.

Clinical characteristics and long-term outcomes for patients who undergo cytoreductive surgery for thoracic meningiomas: a retrospective analysis

OBJECTIVE

Primary spinal meningiomas represent a rare indolent neoplasm usually situated in the intradural-extramedullary compartment. They have a predilection for afflicting the thoracic spine and most frequently present with sensory and/or motor symptoms. Resection is the first-line treatment for symptomatic tumors, whereas other clinical factors will determine the need for adjuvant therapy. In this study, the authors aimed to elucidate clinical presentation, functional outcomes, and long-term outcomes in this population in order to better equip clinicians with the tools to counsel their patients.

METHODS

This is a retrospective analysis of patients treated at the authors' institution between 1998 and 2018. All patients with thoracic meningiomas who underwent resection and completed at least one follow-up appointment were included. Multiple preoperative clinical variables, hospitalization details, and long-term outcomes were collected for the cohort.

RESULTS

Forty-six patients who underwent resection for thoracic meningiomas were included. The average age of the cohort was 59 years, and the median follow-up was 53 months. Persistent sensory and motor symptoms were present in 29 patients (63%). Fifteen lesions were ventrally positioned. There were 43 WHO grade I tumors, 2 WHO grade II tumors, and 1 WHO grade III tumor; the grade III tumor was the only case of recurrence. The median length of hospitalization was 4 days. Seventeen patients (37%) were discharged to rehabilitation facilities. Thirty patients (65.2%) experienced resolution or improvement of symptoms, and there were no deaths within 30 days of surgery. Only 1 patient developed painful kyphosis and was managed medically. Ventral tumor position, new postoperative deficits, and length of stay did not correlate with disposition to a facility. Age, ventral position, blood loss, and increasing WHO grade did not correlate with length of stay.

CONCLUSIONS

Outcomes are overall favorable for patients who undergo resection of thoracic meningiomas. Symptomatic patients often experience improvement, and patients generally do not require significant future operations. Tumors located ventrally, while anatomically challenging, do not necessarily herald a significantly worse prognosis or limit the extent of resection.

Differences in the expression of SSTR1-5 in meningiomas and its therapeutic potential

Beyond microsurgical resection and radiation therapy, there are currently no established treatment alternatives for meningioma patients. In selected cases, peptide radio receptor therapy (PRRT) can be implemented. For this purpose, a radionuclide is bound to a substance targeting specific receptors in meningiomas. One of them is somatostatin receptor 2, which can be found in most meningiomas. However, other somatostatin receptors (SSTR) exist, but their expressions have only been described in small case series. In this study, we analyzed the expression of SSTR1, 2A, 3, 4, and 5 in a large cohort of meningiomas in order to enable further refinement of this innovative treatment option. Overall, 726 tumor samples were processed into tissue microarrays and stained for SSTR1, 2A, 3, 4, and 5 immunohistochemically. Microscopic evaluation was done with an established semiquantitative score regarding percentual quantification and staining intensity, and results were correlated with clinical data. There was a significant lower rate of SSTR1 expression in meningiomas of male patients. Older age was associated with higher expression of SSTR1, 2A, and 5 and lower scores for SSTR3 and 4. Tumors treated with radiotherapy before resection showed lower rates of SSTR1 and 5 expression, while recurrent meningiomas had lower SSTR1 scores. Tumor tissue from patients suffering from neurofibromatosis type 2 had lower expression scores for SSTR1, 2, and 5. For SSTR3 and 4, NF2 patients showed higher scores than sporadic tumors. Spinal meningiomas had higher scores for SSTR1, 4, and 5 compared tumor location of the skull base and convexity/falx. Overall, higher WHO grade was associated with lower SSTR scores. While all SSTRs were expressed, there are marked differences of SSTR expression between meningioma subgroups. This has the potential to drive the development of more selective PRRT substances with higher treatment efficacy.

Epidemiology and survival of patients with spinal meningiomas: A SEER analysis

BACKGROUND

The objective of this study is to determine the population-based estimates of the epidemiology, incidence, and outcomes of spinal meningiomas.

METHODS

The data of patients with spinal meningiomas diagnosed between 2004 and 2016 were extracted from the SEER database. Descriptive analyses were conducted to evaluate the distribution and tumor-related characteristics of patients with spinal meningiomas. Multivariate logistic regression analysis was performed to predict which patients were inclined to be diagnosed with borderline or malignant spinal meningiomas. Possible prognostic indicators were analyzed by Kaplan-Meier curves and the Cox proportional hazards model.

RESULTS

The age-adjusted incidence rate was 0.37 cases per 1,000,000 person-years between 2004 and 2016. Spinal meningiomas represented 4.25% of all meningiomas. A total of 4204 patients with spinal meningiomas were included in our study. Most of the patients were white and diagnosed at 60-69 years of age, and the female:male ratio was 4:1. Most of the tumors were benign and less than 3 cm in size. The most common pathological type was psammomatous meningioma. Surgery was the first choice of treatment for patients with spinal meningiomas. Male and pediatric patients were more vulnerable to borderline or malignant spinal meningiomas. Survival analysis showed that married, female, and younger patients with benign meningiomas had better overall survival than their counterparts.

CONCLUSION

Spinal meningiomas are relatively rare lesions with a favorable prognosis. Psammomatous meningioma is the most common subtype. Male and pediatric patients are more frequently diagnosed with borderline or malignant spinal meningiomas. Surgery is the primary choice of treatment.

Predictive Value of Heterogeneously Enhanced Magnetic Resonance Imaging Findings With Computed Tomography Evidence of Calcification for Severe Motor Deficits in Spinal Meningioma

OBJECTIVE

Spinal meningioma is mostly benign, but they can exhibit neurological deficit. The relationship between neurological impairment and its radiographic findings, including intratumor magnetic resonance imaging (MRI) gadolinium enhancement and calcification in computed tomography (CT) scan, has not been studied. The purpose of this study was to investigate the association of preoperative image findings with neurological status in spinal meningioma.

METHODS

Patients histologically diagnosed with spinal meningioma (n = 24), with an average age of 65.4 years, were included. The patients were classified into 2 groups, the homogeneous and heterogeneous groups, based on the contrast-enhanced T1-weighted MRI findings. Further, baseline demographics (age, sex, presence of preoperative paralysis [manual muscle testing 3 or worse neurological deficit in upper and/or lower limbs], tumor level, tumor length, and tumor occupation ratio), histological findings (Ki-67 index and histological subtypes), and CT findings (presence of intratumor calcification and Hounsfield unit [HU] value) were examined.

RESULTS

Preoperative paralysis was observed in 33.3% (8 of 24) of the patients. These patients exhibited frequent heterogeneous contrast-enhanced MRI findings than those without preoperative paralysis (57.1% vs. 14.3%, p = 0.040). Further, preoperative paralysis did not associate with tumor level, tumor length, tumor-occupied ratio, Ki-67 index, and histological subtypes. The heterogeneous group showed 100% intratumor calcification and higher maximum HU than the homogeneous group (1,109.8 vs. 379.2, p = 0.001).

CONCLUSION

The heterogeneous contrast-induced MRI findings in the spinal meningioma were significantly associated with preoperative neurological impairment. Moreover, the intratumor contrast-deficient region in the heterogeneously enhanced tumors reflected marked calcification. The tumor hardness due to calcification may be related to preoperative neurological deficit.

Differences and characteristics of symptoms by tumor location, size, and degree of spinal cord compression: a retrospective study on 53 surgically treated, symptomatic spinal meningiomas

OBJECTIVE

The differences in symptoms of spinal meningiomas have rarely been discussed from the perspective of tumor characteristics. The main purpose of this paper was to define the differences, if any, in symptoms in patients with spinal meningiomas with respect to tumor size, location, and degree of spinal cord compression. The authors also sought the threshold of spinal cord compression that causes motor weakness.

METHODS

The authors conducted a retrospective study of 53 cases of spinal meningiomas that were surgically treated from 2013 to 2018. Symptoms related to the tumor were classified as motor weakness, sensory disturbance, pain, and bowel/bladder dysfunction. Based on MR images, tumor location was classified by spinal level and by its attachment to the dura mater. Tumor dimensions were also measured. Occupation ratios of the tumors to the spinal canal and degree of spinal cord flattening were sought from the axial MR images that showed the highest degree of spinal cord compression.

RESULTS

Motor weakness and sensory disturbance were significantly more common in thoracic spine meningiomas than in cervical spine meningiomas (p < 0.001 and p = 0.013, respectively), while pain was more common in meningiomas at the craniovertebral junction (p < 0.001). The attachment, height, width, depth, and volume of the tumor showed no significant difference irrespective of the presence or absence of each symptom. In cases of motor weakness and sensory disturbance, occupation ratios and spinal cord flattening ratios were significantly larger. However, these ratios were significantly smaller in the presence of pain. Multivariate logistic regression analysis revealed that occupation ratio independently contributed to motor weakness (OR 1.14, p = 0.035) and pain (OR 0.925, p = 0.034). Receiver operating characteristic curve analysis suggested that occupation ratio with a value of 63.678% is the threshold for the tumor to cause motor weakness.

CONCLUSIONS

The study showed the difference in clinical presentation of spinal meningiomas by spinal level, occupation ratio, and spinal cord flattening ratio. An occupation ratio of approximately 64% could be utilized as the threshold value of tumor growth to cause motor weakness. Tumor growth in the cervical spine might cause pain symptoms before causing motor weakness. The relationship between the tumor and its symptomatology should be discussed with respect to tumor size relative to the surrounding spinal canal.

Spinal meningiomas: is Simpson grade II resection radical enough?

BACKGROUND

The optimal treatment for spinal meningioma is complete resection. The radicality of resection is the most important predictive factor for future tumor recurrence. Although clinical series dedicated to spinal meningiomas are relatively frequent, only a minimum of these defines the length of the required follow-up and difference in tumor recurrence in the context of Simpson grade I and II resection. Therefore, we propose reconsideration of surgical treatment and long-term follow-up based on a retrospective analysis of 84 patients who underwent Simpson grade II resection.

METHODS

The study included 84 patients operated between 1998 and 2018. Clinical symptomatology, age, sex, risk of comorbidities, spinal level, duration of symptoms, surgical resection radicality, tumor recurrence, and complications associated with treatment were recorded and evaluated.

RESULTS

We encountered the diagnosis of spinal meningioma considerably more often in women (81%) than in men (19%). The average age of all patients was 65 years. Most meningiomas were located in the thoracic spine (82%) while the rest (18%) were located in the cervical spine. The most common symptoms were motor deficit (80%) and sensation disorders (70%). Of the symptomatic patients, 71% clinically improved, 27% showed no change and 2% worsened postoperatively. The mean follow-up was 32 months (range 1-204). During this period, there was a 5% tumor recurrence rate. However, when we analyzed a subgroup of nine patients who were monitored for more than 6 years, tumor recurrence was diagnosed in 44%, all of whom were women (mean age 51 years).

CONCLUSION

Our results indicate that tumor recurrence after Simpson II resection could be significantly higher than previously thought if the follow-up is long enough, especially in younger patients. This finding suggests we consider using radical Simpson grade I resection more frequently. The study also demonstrates that after spinal meningioma surgery the patients should be followed and monitored on a long-term basis.

Spinal Clear Cell Meningiomas: Clinical Features and Factors Predicting Recurrence

OBJECTIVE

As a World Health Organization grade II tumor of the nervous system, clear cell meningioma (CCM) is an uncommon histologic variant of meningioma. Spinal CCMs are even rarer, with <100 spinal CCMs reported in the English literature. We present this study to characterize clinical manifestations of spinal CCMs and determine the factors predicting recurrence.

METHODS

A literature search was performed for relevant case reports and series in PubMed and Embase until September 1, 2019. These articles were reviewed to identify clinical features, treatment modalities, and prognosis of patients with spinal CCMs.

RESULTS

Eighty-four spinal CCMs were analyzed. Of these patients, 36 (42.9%) were young (age ≤18 years), and the mean age at resection was 24 years. Fifty-three patients (63.1%) were female and 31 (36.9%) were male. Most of the tumors (56/84, 66.7%) were located in the lumbar region. In 31 patients (36.9%) >2 segments in the craniocaudal direction were involved (number of involved segments ≥3 levels). Gross tumor resection was performed in 77 patients (91.7%). Twenty patients (23.8%) showed radiographic evidence of recurrence during follow-up. Recurrence-free survival at 1, 5, and 10 years after resection of spinal CCM was 87%, 71%, and 47%, respectively. Multivariate analysis showed that age ≤18 years (hazard ratio [HR], 3.64; P = 0.024), subtotal resection (HR, 3.43; P = 0.031), and segments involving ≥3 levels (HR, 5.66; P = 0.002) were associated with increased recurrence.

CONCLUSIONS

Spinal CCMs have their own unique clinical features compared with conventional spinal meningiomas and intracranial CCMs. Spinal CCMs have a predilection to affect younger patients, are prone to appear in the lumbar region, and have a high recurrence rate. Age ≤18 years, subtotal resection, and involvement of long segments (≥3 levels) are positive predictors of recurrence.

Neuro-oncological features of spinal meningiomas: Systematic review

PURPOSE

Review the published data on spinal meningioma (SM) to create a more comprehensive picture of its natural history.

METHODS

A review of the published SM literature was carried out through a Medline search up to December 2018. The search using the keyword "spinal meningiomas" returned 248 papers and the parameters analyzed in our present study were examined in those publications. Papers without a detailed description of clinical findings, neuroimaging confirmation of the spinal tumor, minimum follow-up of 5 years, or a clear description of the clinical findings were excluded.

RESULTS

In the 24 manuscripts reviewed, 1811 (1450 females/361 males) patients with SM were analyzed. The thoracic spine (1181-64.6%) and cervical spine (394-22.7%) were the more prevalent levels. The psammomatous (27.8%) and meningothelial variants (25.2%) were the most prevalent histopathological subtypes. Gross total resection (Simpson I and II) was achieved in 94.5% of cases and subtotal resection (Simpson III or more) in 5.5%. The tumor recurrence rate was 4.4%, and the mortality rate related to surgery or disease progression was 3%.

CONCLUSION

WHO grade I predominance was observed among spinal meningiomas, analogous to intracranial meningiomas. SMs predominated in the thoracic spine. Surgery with gross total resection was achieved in the vast majority of cases, resulting in low recurrence and mortality rates.

Reduced field of view echo-planar imaging diffusion tensor MRI for pediatric spinal tumors

OBJECTIVE

Spine MRI is a diagnostic modality for evaluating pediatric CNS tumors. Applying diffusion-weighted MRI (DWI) or diffusion tensor imaging (DTI) to the spine poses challenges due to intrinsic spinal anatomy that exacerbates various image-related artifacts, such as signal dropouts or pileups, geometrical distortions, and incomplete fat suppression. The zonal oblique multislice (ZOOM)-echo-planar imaging (EPI) technique reduces geometric distortion and image blurring by reducing the field of view (FOV) without signal aliasing into the FOV. The authors hypothesized that the ZOOM-EPI method for spine DTI in concert with conventional spinal MRI is an efficient method for augmenting the evaluation of pediatric spinal tumors.

METHODS

Thirty-eight consecutive patients (mean age 8 years) who underwent ZOOM-EPI spine DTI for CNS tumor workup were retrospectively identified. Patients underwent conventional spine MRI and ZOOM-EPI DTI spine MRI. Two blinded radiologists independently reviewed two sets of randomized images: conventional spine MRI without ZOOM-EPI DTI, and conventional spine MRI with ZOOM-EPI DTI. For both image sets, the reviewers scored the findings based on lesion conspicuity and diagnostic confidence using a 5-point Likert scale. The reviewers also recorded presence of tumors. Quantitative apparent diffusion coefficient (ADC) measurements of various spinal tumors were extracted. Tractography was performed in a subset of patients undergoing presurgical evaluation.

RESULTS

Sixteen patients demonstrated spinal tumor lesions. The readers were in moderate agreement (kappa = 0.61, 95% CI 0.30-0.91). The mean scores for conventional MRI and combined conventional MRI and DTI were as follows, respectively: 3.0 and 4.0 for lesion conspicuity (p = 0.0039), and 2.8 and 3.9 for diagnostic confidence (p < 0.001). ZOOM-EPI DTI identified new lesions in 3 patients. In 3 patients, tractography used for neurosurgical planning showed characteristic fiber tract projections. The mean weighted ADCs of low- and high-grade tumors were 1201 × 10-6 and 865 × 10-6 mm2/sec (p = 0.002), respectively; the mean minimum weighted ADCs were 823 × 10-6 and 474 × 10-6 mm2/sec (p = 0.0003), respectively.

CONCLUSIONS

Diffusion MRI with ZOOM-EPI can improve the detection of spinal lesions while providing quantitative diffusion information that helps distinguish low- from high-grade tumors. By adding a 2-minute DTI scan, quantitative diffusion information and tract profiles can reliably be obtained and serve as a useful adjunct to presurgical planning for pediatric spinal tumors.