Clinical features and prognostic factors in spinal meningioma surgery from a multicenter study

Resection vs. coagulation of dural attachment in patients with spinal meningioma: an updated systematic review and meta-analysis

BACKGROUND

The Simpson grading scale assumes dural resection (grade I) is more effective against recurrence than coagulation (grade II). However, the results of recent studies have raised doubts about this effectiveness in spinal meningiomas. Therefore, we aimed to perform a meta-analysis comparing outcomes between Simpson grades I and II in spinal meningiomas.

METHODS

According to the PRISMA statement, we systematically searched PubMed, EMBASE, and Web of Science for studies involving patients with spinal meningiomas who underwent Simpson grades I, II, III, or IV. Outcomes were radiological tumor recurrence, postoperative neurological deficits, and procedure-related complications.

RESULTS

We included 54 studies with a total of 3334 patients. Simpson grades I, II, III, and IV were performed in 674 (20%), 2205 (66%), 254 (8%), and 201 (6%) patients, respectively. The follow-up ranged from 9 to 192 months, and 95.4% of all tumors were WHO grade 1. There was no difference in radiological tumor recurrence (OR 0.80, 95% CI: 0.46-1.36, P = 0.41; I2 = 0%), postoperative neurological deficits (OR 0.74, 95% CI: 0.32-1.75, P = 0.50; I2 = 0%) or procedure-related complications (OR 2.22, 95% CI: 0.80-6.13, P = 0.12; I2 = 3%) between Simpson grades I and II. Furthermore, no significant difference in postoperative neurological deficits or procedure-related complications was detected when comparing all Simpson's to each other. However, radiological tumor recurrences in Simpson I and II were significantly lower than in III and IV, with Simpson III outperforming IV (OR 0.19, 95% CI: 0.09-0.40, P < 0.01; I2 = 0%).

CONCLUSION

Simpson grade I is not more effective than grade II in any outcome, although both are superior to III and IV in tumor recurrence. Our results might suggest that dural coagulation is preferable over resection when the latter carries a higher risk of complications.

Unusual clinical presentation of cervical extradural meningioma detected with neuromuscular ultrasound: A case report

Extradural meningiomas are rare in the cervical region. A total of 70-77% of reported cases have occurred in the thoracic region. Tumors that occur in the cervical region may invade the adjacent nerve root and brachial plexus. Typically, diagnoses of extradural meningioma are made after patients present with signs of myelopathy, such as progressive paresis and numbness. In the current study, a 64-year-old male patient presented with neck pain, numbness and mild weakness in the left hand over a 6-month period. The general neurological examination was unremarkable, except for mild grasping weakness on the left side. Needle electromyography revealed complex repetitive discharges in the left 5 and 6th cervical paraspinal muscles. Neuromuscular ultrasound revealed a lesion over the left 7th cervical root, which enabled the early detection of an extradural meningioma before notable focal neurological defects developed. The patient underwent a subtotal tumor excision, followed by radiotherapy for residual tumor. Histopathological examination confirmed atypical meningioma.

Spinal Meningiomas: A Comprehensive Review and Update on Advancements in Molecular Characterization, Diagnostics, Surgical Approach and Technology, and Alternative Therapies

Spinal meningiomas are the most common intradural, extramedullary tumor in adults, yet the least common entity when accounting for all meningiomas spanning the neuraxis. While traditionally considered a benign recapitulation of their intracranial counterpart, a paucity of knowledge exists regarding the differences between meningiomas arising from these two anatomic compartments in terms of histopathologic subtypes, molecular tumor biology, surgical principles, long-term functional outcomes, and recurrence rates. To date, advancements at the bench have largely been made for intracranial meningiomas, including the discovery of novel gene targets, DNA methylation profiles, integrated diagnoses, and alternative systemic therapies, with few exceptions reserved for spinal pathology. Likewise, evolving clinical research offers significant updates to our understanding of guiding surgical principles, intraoperative technology, and perioperative patient management for intracranial meningiomas. Nonetheless, spinal meningiomas are predominantly relegated to studies considering non-specific intradural extramedullary spinal tumors of all histopathologic types. The aim of this review is to comprehensively report updates in both basic science and clinical research regarding intraspinal meningiomas and to provide illustrative case examples thereof, thereby lending a better understanding of this heterogenous class of central nervous system tumors.

Ventro-Lateral Meningioma of the Cervico-Thoracic Junction: 2-Dimensional Operative Video

Meningiomas are one of the most common intradural extramedullary tumors.1 Symptoms often arise from cord compression, with gross total resection leading to the most optimal patient outcomes.2,3 Utilization of intraoperative neurophysiological monitoring can increase patient safety through real-time assessment of neural structures and reduce postoperative neurologic complications.4 In this video, we describe the operative techniques for the resection of a meningioma located at the cervico-thoracic junction. A 43-year-old female patient presented with 6 months of bilateral leg numbness and gait disturbances. MRI of the cervical spine demonstrated a cervical thoracic ventral meningioma causing severe cord compression from the bottom of the C6 lamina to the top of the T1 lamina. Surgical resection with intraoperative neuromonitoring with somatosensory-evoked potentials, motor-evoked potentials, and free-running electromyography was recommended. A partial C6-T1 laminectomy was routinely performed, and the dura was opened using a paramedian approach to allow for maximal tumor visualization. The tumor was carefully dissected and debulked, achieving gross total resection. Postoperatively, the patient experienced improvements in preoperative symptoms with no perioperative complications, and the final pathology confirmed the intradural lesion was a meningioma. This video illustrates the surgical technique and management of a spinal meningioma at the cervico-thoracic junction. Patient consent was obtained for their participation in this surgical video.

Epidemiology and survival of patients with spinal meningiomas: a large retrospective cohort study

INTRODUCTION

Spinal meningiomas (SMs) are relatively rare central nervous system tumors that usually trigger neurological symptoms. The prevalence of SMs is increasing with the aging of the global population. This study aimed to perform a systematic epidemiologic and survival prognostic analysis of SMs to evaluate their public health impact and to develop a novel method to estimate the overall survival at 3-year, 5-year, and 10-year in patients with SMs.

METHODS

Five thousand one hundred fifty eight patients with SMs were recruited from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2019. Firstly, descriptive analysis was performed on the epidemiology of SMs. Secondly, these individuals were randomly allocated to the training and validation sets in a ratio of 7:3. Kaplan-Meier method and Cox regression analysis were utilized in the training set to identify independent prognostic factors and to construct a nomogram for survival prognosis. Subsequently, the discriminative power, predictive performance, and clinical utility of the nomogram were evaluated by receiver operating characteristic curve and decision curve analysis. Finally, a mortality risk stratification system and a web-based dynamic nomogram were constructed to quantify the risk of mortality in patients with SMs.

RESULTS

The annual age-adjusted incidence rates of SMs increased steadily since 2004, reaching a rate of 0.40 cases per 100 000 population in 2019, with a female-to-male ratio of ~4:1. The age groups of 50-59, 60-69, and 70-79 years old were the most prevalent ages for SMs, accounting for 19.08, 24.93, and 23.32%, respectively. In addition, seven independent prognostic factors were identified to establish a prognostic nomogram for patients with SMs. The decision curve analysis and receiver operating characteristic curve indicated that the nomogram had high clinical utility and favorable accuracy. Moreover, the mortality risk stratification system effectively divided patients into low-risk, middle-risk, and high-risk subgroups.

CONCLUSIONS

SMs are relatively rare benign spinal tumors prevalent in the white elderly female population. Clinicians could use the nomogram to personalize the prediction of the overall survival probability of patients with SMs, categorize these patients into different mortality risk subgroups, and develop personalized decision-making plans. Moreover, the web-based dynamic nomogram could help to further promote clinical application and assist clinicians in providing personalized counseling, timely monitoring, and clinical assessment for patients.

Cervical spinal meningioma mimicking an arachnoid cyst: A pediatric case report

Background

Meningiomas are rare tumors in children. Although magnetic resonance imaging (MRI) diagnosis is usually easy, its cystic form can wrongly suggest other diagnoses, such as an epidermoid or arachnoid cyst. We describe an unusual case of cervical cystic meningioma in a child.

Case Description

A 5-year-old patient was consulted for progressive weakness of all four limbs, making walking impossible. Neurological examination revealed cervical stiffness without meningeal signs and tetrapyramidal syndrome with incomplete tetraplegia. A cervical spine MRI showed a circumscribed intradural extramedullary lesion at the level of C2-C3, which led to a suspicion of a compressive arachnoid cyst. A gross total resection was performed through a posterior approach. During surgery, it was an extramedullary intradural cystic formation containing a clear liquid and a shell adherent to the Dura mater. Postoperative MRI shows satisfactory spinal cord decompression without evidence of residual tumor. The postoperative course was uneventful, with the resumption of independent walking on the 21st day. Histopathologic examination and immunohistochemistry revealed a grade I meningothelial meningioma according to the 2021 World Health Organization classification of tumors of the central nervous system.

Conclusion

Cystic meningiomas can sometimes suggest another diagnosis on imaging, especially since they are rare in children.

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.

Postoperative neurological complications in intradural extramedullary tumors: A 10-year experience of a single center

BACKGROUND

Intradural extramedullary spinal cord tumors (IDEMs) cause neurological symptoms due to compression of the spinal cord and caudal nerves. The purpose of this study was to investigate the incidence of postoperative neurological complications after surgical resection of IDEM and to identify factors associated with such postoperative neurological complications.

METHODS

We retrospectively analyzed 85 patients who underwent tumor resection for IDEM between 2010 and 2020. We investigated the postoperative worsening of neurological disorders. The patients were divided into two groups: those with and without postoperative neurological complications. Patient demographic characteristics, tumor level, histological type, and surgery-related factors were also compared.

RESULTS

The mean age at the time of surgery was 57.4 years, and histological analysis revealed 45 cases of schwannoma, 34 cases of meningioma, three cases of myxopapillary ependymoma, one case of ependymoma, one case of hemangioblastoma and one case of lipoma. There were five cases (5.8%) of postoperative neurological complications, and four patients improved within 6 months after surgery, and one patient had residual worsening. There were no statistically significant differences in age, sex, tumor location, preoperative modified McCormick Scale grade, histology, tumor occupancy, or whether fixation was performed in the presence or absence of postoperative neurological complications. All four cases of meningioma with postoperative neurological complications had preoperative neuropathy and meningiomas were located in the anterior or lateral thoracic spine.

CONCLUSIONS

Neurological complications after surgical resection for IDEM occurred in 5.8% of patients. Meningiomas with postoperative neurological complications located anteriorly or laterally in the thoracic spine.

Predictors of Cerebrospinal Fluid Leak Following Dural Repair in Spinal Intradural Surgery

OBJECTIVE

We aim to compare the effectiveness of dural closure techniques in preventing cerebrospinal fluid (CSF) leaks following surgery for intradural lesions and seek to identify additional factors associated with CSF leaks. Surgical management of spinal intradural lesions involves durotomy which requires a robust repair to prevent postoperative CSF leakage. The ideal method of dural closure and the efficacy of sealants has not been established in literature.

METHODS

We performed a retrospective analysis of all intradural spinal cases performed at a tertiary spine centre from 1 April 2015 to 29 January 2020 and collected data on patient bio-profile, dural repair technique, and CSF leak rates. Multivariate analysis was performed to identify predictors for postoperative CSF leak.

RESULTS

A total of 169 cases were reported during the study period. There were 15 cases in which postoperative CSF leak was reported (8.87%). Multivariate analysis demonstrated that patient age (odds ratio [OR], 0.942; 95% confidence interval [CI], 0.891-0.996), surgical indication listed in the "others" category (OR, 44.608; 95% CI, 1.706-166.290) and dural closure with suture, sealant and patch (OR, 22.235; 95% CI, 2.578-191.798) were factors associated with CSF leak. Postoperative CSF leak was associated with the risk of surgical site infection with a likelihood ratio of 8.704 (χ² (1) = 14.633, p < 0.001).

CONCLUSION

Identifying predictors for CSF leaks can assist in the counselling of patients with regard to surgical risk and expected postoperative recovery.

Update on meningioma: Clinical-radiological and radio-pathological correlation

Meningiomas are tumors that originate in the arachnoid villi and are the most common non-glial neoplasm in the central nervous system. The clinical manifestations associated with meningioma depend, fundamentally, on its location. The location in the cerebral convexity is the most frequent, especially in the frontal lobes, manifesting with headache, motor disturbances, seizures and even neurocognitive disorders. There are 15 histologic subtypes of meningioma and three histologic grades. Within these, grades two and three have a worse prognosis and a higher rate of recurrence, as well as a radiological behavior that is generally more aggressive. Although there are some imaging features that can suggest a specific subtype, the definitive diagnosis will always require histological/molecular confirmation.

Clinical diagnosis model of spinal meningiomas based on the surveillance, epidemiology, and end results database

Most spinal meningiomas (SM) are benign lesions of the thoracic spine and are usually treated surgically. This study aimed to explore treatment strategies and construct a nomogram for SM. Data on patients with SM from 2000 to 2019 were extracted from the Surveillance, Epidemiology, and End Results database. First, the distributional properties and characteristics of the patients were descriptively evaluated, and the patients were randomly divided into training and testing groups in a 6:4 ratio. Least absolute shrinkage and selection operator (LASSO) regression was used to screen the survival predictors. Kaplan-Meier curves explained survival probability by different variables. The nomogram was constructed based on the results of LASSO regression. The predictive power of the nomogram was identified using the concordance index, time-receiver operating characteristics, decision curve analysis, and calibration curves. We recruited 1,148 patients with SM. LASSO results for the training group showed that sex (coefficient, 0.004), age (coefficient, 0.034), surgery (coefficient, -0.474), tumor size (coefficient, 0.008), and marital status (coefficient, 0.335) were prognostic factors. The nomogram prognostic model showed good diagnostic ability in both the training and testing groups, with a C-index of 0.726, 95% (0.679, 0.773); 0.827, 95% (0.777, 0.877). The calibration and decision curves suggested that the prognostic model had better diagnostic performance and good clinical benefit. In the training and testing groups, the time-receiver operating characteristic curve showed that SM had moderate diagnostic ability at different times, and the survival rate of the high-risk group was significantly lower than that of the low-risk group (training group: p = 0.0071; testing group: p = 0.00013). Our nomogram prognostic model may have a crucial role in predicting the six-month, one-year, and two-year survival outcomes of patients with SM and may be useful for surgical clinicians to formulate treatment plans.

Spinal meningiomas, from biology to management - A literature review

Meningiomas arise from arachnoidal cap cells of the meninges, constituting the most common type of central nervous system tumors, and are considered benign tumors in most cases. Their incidence increases with age, and they mainly affect females, constituting 25-46% of primary spinal tumors. Spinal meningiomas could be detected incidentally or be unraveled by various neurological symptoms (e.g., back pain, sphincter dysfunction, sensorimotor deficits). The gold standard diagnostic modality for spinal meningiomas is Magnetic resonance imaging (MRI) which permits their classification into four categories based on their radiological appearance. According to the World Health Organization (WHO) classification, the majority of spinal meningiomas are grade 1. Nevertheless, they can be of higher grade (grades 2 and 3) with atypical or malignant histology and a more aggressive course. To date, surgery is the best treatment where the big majority of meningiomas can be cured. Advances in surgical techniques (ultrasonic dissection, microsurgery, intraoperative monitoring) increase the complete resection rate. Operated patients have a satisfactory prognosis, even in those with poor preoperative neurological status. Adjuvant therapy has a growing role in treating spinal meningiomas, mainly in the case of subtotal resection and tumor recurrence. The current paper reviews the fundamental epidemiological and clinical aspects of spinal meningiomas, their histological and genetic characteristics, and their management, including the various surgical novelties and techniques.

Mother and daughter with a SMARCE1 mutation resulting in a cervical clear cell meningioma at an identical location: illustrative cases

BACKGROUND

A rare meningioma subtype is a clear cell (CC) meningioma, which can be associated with a SMARCE1 gene mutation. Manifestation of a CC meningioma in the cervical spine is unusual. In the current case, both mother and daughter present with a CC meningioma at an identical cervical location.

OBSERVATIONS

A 67-year-old patient with an intradural extramedullary mass at the level of C5 presented with progressive myelopathy. The mass was resected through a ventral approach by a two-level corpectomy with an expandable cage and instrumentation. The daughter of this patient appeared to have had an intradural extramedullary mass at C5 at the age of 20, which was resected through a posterior approach. Pathological investigation of both tumors revealed CC meningioma. Genetic testing of the daughter revealed a SMARCE1 mutation.

LESSONS

It is of major importance to consider a SMARCE1 mutation in elderly presenting with a CC meningioma, which is still uncommon in current practice. This could lead to timely diagnostics in the succeeding generation. Complete resection of a CC meningioma is important because of the high recurrence rate. Routine follow-up should therefore be performed in the postoperative period. An anterior approach should be considered for a ventral cervical CC meningioma.

A current review of spinal meningiomas: epidemiology, clinical presentation and management

PURPOSE

To provide an up-to-date review of the epidemiology, histopathology, molecular biology, and etiology of spinal meningiomas, as well as discuss the clinical presentation, clinical evaluation, and most recent treatment recommendations for these lesions.

METHODS

PubMed and Google Scholar search was performed for studies related to meningiomas of the spine. The terms "meningioma," "spinal meningioma," "spine meningioma," "meningioma of the spine," "benign spinal tumors," and "benign spine tumors," were used to identify relevant studies. All studies, including primary data papers, meta-analyses, systematic reviews, general reviews, case reports, and clinical trials were considered for review.

RESULTS

Eighty-four studies were identified in the review. There were 22 studies discussing adverse postoperative outcomes, 21 studies discussing tumor genetics, 19 studies discussing epidemiology and current literature, 9 studies discussing radiation modalities and impact on subsequent tumor development, 5 studies on characteristic imaging findings, 5 studies discussing hormone use/receptor status on tumor development, 2 discussing operative techniques and 1 discussing tumor identification.

CONCLUSION

Investigations into spinal meningiomas generally lag behind that of intracranial meningiomas. Recent advancements in the molecular profiling of spinal meningiomas has expanded our understanding of these tumors, increasing our appreciation for their heterogeneity. Continued investigation into the defining characteristics of different spinal meningiomas will aid in treatment planning and prognostication.

Current Knowledge on Spinal Meningiomas Epidemiology, Tumor Characteristics and Non-Surgical Treatment Options: A Systematic Review and Pooled Analysis (Part 1)

BACKGROUND

Spinal meningiomas are the most common primary intradural spinal tumors. Although they are a separate entity, a large portion of the knowledge on spinal meningiomas is based on findings in intracranial meningiomas. Therefore, a comprehensive review of all the literature on spinal meningiomas was performed.

METHODS

Electronic databases were searched for all studies on spinal meningiomas dating from 2000 and onward. Findings of matching studies were pooled to strengthen the current body of evidence.

RESULTS

A total of 104 studies were included. The majority of patients were female (72.83%), elderly (peak decade: seventh), and had a world health organization (WHO) grade 1 tumor (95.7%). Interestingly, the minority of pediatric patients had a male overrepresentation (62.0% vs. 27.17%) and higher-grade tumors (33.3% vs. 4.3%). Sensory and motor dysfunction and pain were the most common presenting symptoms. Despite a handful of studies reporting promising findings associated with the use of non-surgical treatment options, the literature still suffers from contradictory results and limitations of study designs.

CONCLUSIONS

Elderly females with WHO grade 1 tumors constituted the stereotypical type of patient. Compared to surgical alternatives, the evidence for the use of non-surgical treatments is still relatively weak.

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.

Characterization and Treatment of Spinal Tumors

The prevalence of spinal tumors is rare in comparison to brain tumors which encompass most central nervous system tumors. Tumors of the spine can be divided into primary and metastatic tumors with the latter being the most common presentation. Primary tumors are subdivided based on their location on the spinal column and in the spinal cord into intramedullary, intradural extramedullary, and primary bone tumors. Back pain is a common presentation in spine cancer patients; however, other radicular pain may be present. Magnetic resonance imaging (MRI) is the imaging modality of choice for intradural extramedullary and intramedullary tumors. Plain radiographs are used in the initial diagnosis of primary bone tumors while Computed tomography (CT) and MRI may often be necessary for further characterization. Complete surgical resection is the treatment of choice for spinal tumors and may be curative for well circumscribed lesions. However, intralesional resection along with adjuvant radiation and chemotherapy can be indicated for patients that would experience increased morbidity from damage to nearby neurological structures caused by resection with wide margins. Even with the current treatment options, the prognosis for aggressive spinal cancer remains poor. Advances in novel treatments including molecular targeting, immunotherapy and stem cell therapy provide the potential for greater control of malignant and metastatic tumors of the spine.

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.

MAC-spinal meningioma score: A proposal for a quick-to-use scoring sheet of the MIB-1 index in sporadic spinal meningiomas

Objective

MIB-1 index is an important predictor of meningioma progression. However, MIB-1 index is not available in the preoperative tailored medical decision-making process. A preoperative scoring sheet independently estimating MIB-1 indices in spinal meningioma (SM) patients has not been investigated so far.

Methods

Between 2000 and 2020, 128 patients with clinical data, tumor imaging data, inflammatory laboratory (plasma fibrinogen, serum C-reactive protein) data, and neuropathological reports (MIB-1, mitotic count, CD68 staining) underwent surgery for spinal WHO grade 1 and 2 meningioma.

Results

An optimal MIB-1 index cut-off value (≥5/<5) predicting recurrence was calculated by ROC curve analysis (AUC: 0.83; 95%CI: 0.71-0.96). An increased MIB-1 index (≥5%) was observed in 55 patients (43.0%) and multivariable analysis revealed significant associations with baseline Modified McCormick Scale ≥2, age ≥65, and absence of calcification. A four-point scoring sheet (MAC-Spinal Meningioma) based on Modified McCormick, Age, and Calcification facilitates prediction of the MIB-1 index (sensitivity 71.1%, specificity 60.0%). Among those patients with a preoperative MAC-Meningioma Score ≥3, the probability of a MIB-1 index ≥5% was 81.3%.

Conclusion

This novel score (MAC-Spinal Meningioma) supports the preoperative estimation of an increased MIB-1 index, which might support preoperative patient-surgeon consultation, surgical decision making and enable a tailored follow-up schedule or an individual watch-and-wait strategy.

Functional Outcome in Spinal Meningioma Surgery and Use of Intraoperative Neurophysiological Monitoring

Data on intraoperative neurophysiological monitoring (IOM) during spinal meningioma (SM) surgery are scarce. The aim of this study was to assess the role of IOM and its impact on post-operative functional outcome. Eighty-six consecutive surgically treated SM patients were included. We assessed pre and post-operative Modified McCormick Scale (mMCS), radiological and histopathological data and IOM findings. Degree of cord compression was associated with preoperative mMCS and existence of motor or sensory deficits (p < 0.001). IOM was used in 51 (59.3%) patients (IOM-group). Median pre and post-operative mMCS was II and I, respectively (p < 0.001). Fifty-seven (66.3%) patients showed an improvement of at least one grade in the mMCS one year after surgery. In the IOM group, only one patient had worsened neurological status, and this was correctly predicted by alterations in evoked potentials. Analysis of both groups found no significantly better neurological outcome in the IOM group, but IOM led to changes in surgical strategy in complex cases. Resection of SM is safe and leads to improved neurological outcome in most cases. Both complication and tumor recurrence rates were low. We recommend the use of IOM in surgically challenging cases, such as completely ossified or large ventrolateral SM.

Minimally Invasive Tubular Retractor Surgery for Intradural Extramedullary Spinal Tumor Reduces Postoperative Degeneration of Paraspinal Muscle

Background  Minimally invasive surgery (MIS) using a tubular retractor has been increasingly utilized in spinal surgery for degenerative conditions with the benefit of paraspinal muscle preservation. This benefit has not been previously reported for intradural extramedullary tumors using the MIS approach. In this study, we aimed to compare the degree of postoperative fatty degeneration in paraspinal muscle between MIS with tubular retractor (MIS) and open laminectomy (Open) for intradural extramedullary spinal tumors. Methods  This was a retrospective review conducted in a tertiary neurosurgical center from 2015 to 2019. The degree of paraspinal muscle fatty degeneration, as measured by Goutallier grade on postoperative magnetic resonance imaging (MRI), was analyzed, and the degree of excision, tumor recurrence rate, and chronic pain were compared between the two surgical approaches. Results  Among 9 patients in the MIS group and 33 patients in the Open group, the rate of gross total resection was comparable (MIS: 100.0%, Open: 97.0%, p  = 1.000). The degree of paraspinal muscle fatty degeneration was significantly reduced in the MIS group (median Goutallier grade 1 in MIS group vs. median Goutallier grade 2 in Open group, p  = 0.023). There was no significant difference in the tumor recurrence rate, complication rate, and chronic pain severity. A consistent trend of reduced analgesic consumption was observed in the MIS group, though not statistically significant. Conclusions  Minimally invasive tubular retractor surgery is an effective approach for appropriately selected intradural extramedullary spinal tumors with significantly reduced postoperative fatty degeneration in paraspinal muscle.