Patient Demographics Influencing Vestibular Schwannoma Size and Initial Management Plans

Vestibular Schwannoma International Study of Active Surveillance Versus Stereotactic Radiosurgery: The VISAS Study

PURPOSE

The present study assesses the safety and efficacy of stereotactic radiosurgery (SRS) versus observation for Koos grade 1 and 2 vestibular schwannoma (VS), benign tumors affecting hearing and neurological function.

METHODS AND MATERIALS

This multicenter study analyzed data from Koos grade 1 and 2 VS patients managed with SRS (SRS group) or observation (observation group). Propensity score matching balanced patient demographics, tumor volume, and audiometry. Outcomes measured were tumor control, serviceable hearing preservation, and neurological outcomes.

RESULTS

In 125 matched patients in each group with a 36-month median follow-up (P = .49), SRS yielded superior 5- and 10-year tumor control rates (99% CI, 97.1%-100%, and 91.9% CI, 79.4%-100%) versus observation (45.8% CI, 36.8%-57.2%, and 22% CI, 13.2%-36.7%; P < .001). Serviceable hearing preservation rates at 5 and 9 years were comparable (SRS 60.4% CI, 49.9%-73%, vs observation 51.4% CI, 41.3%-63.9%, and SRS 27% CI, 14.5%-50.5%, vs observation 30% CI, 17.2%-52.2%; P = .53). SRS were associated with lower odds of tinnitus (OR = 0.39, P = .01), vestibular dysfunction (OR = 0.11, P = .004), and any cranial nerve palsy (OR = 0.36, P = .003), with no change in cranial nerves 5 or 7 (P > .05). Composite endpoints of tumor progression and/or any of the previous outcomes showed significant lower odds associated with SRS compared with observation alone (P < .001).

CONCLUSIONS

SRS management in matched cohorts of Koos grade 1 and 2 VS patients demonstrated superior tumor control, comparable hearing preservation rates, and significantly lower odds of experiencing neurological deficits. These findings delineate the safety and efficacy of SRS in the management of this patient population.

Refining the predictive value of preoperative apparent diffusion coefficient (ADC) by whole-tumor analysis for facial nerve outcomes in vestibular schwannomas

BACKGROUND

Apparent diffusion coefficient (ADC) in MRI has been shown to correlate with postoperative House-Brackmann (HB) scores in patients with vestibular schwannoma despite limited methodology. To rectify limitations of single region of interest (ROI) sampling, we hypothesize that whole-tumor ADC histogram analysis will refine the predictive value of this preoperative biomarker related to postoperative facial nerve function.

METHODS

Of 155 patients who underwent resection of vestibular schwannoma (2014-2020), 125 patients were included with requisite clinical and radiographic data. After volumetric analysis and whole-tumor ADC histogram, regression tree analysis identified ADC cutoff for significant differences in HB grade. Outcomes were extent of resection, facial nerve function, hospital length of stay (LOS), and complications.

RESULTS

Regression tree analysis defined three quantitative ADC groups (× 10-6 mm2/s) as high (> 2248.77; HB 1.7), mid (1468.44-2248.77; HB 3.1), and low (< 1468.44; HB 2.3) range (p 0.04). The mid-range ADC group had significantly worse postoperative HB scores and longer hospital LOS. Large tumor volume was independently predictive of lower rates of gross total resection (p <0.0001), higher postoperative HB score (p 0.002), higher rate of complications (p 0.04), and longer LOS (p 0.003).

CONCLUSIONS

Whole-tumor histogram yielded a robust regression tree analysis that defined three ADC groups with significantly different facial nerve outcomes. This likely reflects tumor heterogeneity better than solid-tumor ROI sampling. Whole-tumor ADC warrants further study as a useful radiographic biomarker in patients with vestibular schwannoma who are considering surgical resection.

Disparities in Sporadic Vestibular Schwannoma Initial Presentation Between a Public Safety Net Hospital and Tertiary Academic Medical Center at the Same Zip Code 2010 to 2020

INTRODUCTION

Treatment of vestibular schwannoma (VS) has been extensively studied, but a gap in knowledge exists demonstrating how racial and socioeconomic status influence VS presentation. Our institution has a unique setting with a public safety net hospital (PSNH) and tertiary academic medical center (TAMC) in the same zip code, which we study to evaluate initial VS presentation disparities in patient populations presenting to these hospital settings.

METHODS

Retrospective chart review was performed of all adult patients (n = 531) presenting 2010 to 2020 for initial VS evaluation at TAMC (n = 462) and PSNH (n = 69). Ethnicity, insurance, maximum tumor size, audiometry, initial treatment recommendation, treatment received, and follow up were recorded and statistical analysis performed to determine differences.

RESULTS

Average age at diagnosis (51.7 ± 13.6 TAMC vs 52.3 ± 12.4 PSNH) and gender (58.4% TAMC vs 52.2% PSNH female) were similar. Patients' insurance (TAMC 75.9% privately insured vs PSNH 82% Medicaid) and racial/ethnic profiles (TAMC 67.7% White and 10.0% Hispanic/Latinx, vs PSNH 4.8% White but 59.7% Hispanic/Latinx) were significantly different. Tumor size was larger at PSNH (20.2 ± 13.3 mm) than TAMC (16.6 ± 10.0 mm). Hearing was more impaired at PSNH than TAMC (mean pure tone average 58.3 dB vs 43.9 dB, word recognition scores 52.3% vs 68.2%, respectively). Initial treatment recommendations and treatment received may include more than 1 modality. TAMC patients were offered 66.7% surgery, 31.2% observation, and 5.2% radiation, while PSNH patients offered 50.7% observation, 49.3% surgery, and 8.7% radiation. TAMC patients received 62.9% surgery, 32.5% observation, and 5.3% radiation, while PSNH patients received 36.2% surgery, 59.4% observation, and 14.5% radiation. Follow up and treatment at the same facility was not significantly different between hospitals.

CONCLUSIONS

Hearing was worse and tumor size larger in patients presenting to PSNH. Despite worse hearing status and larger tumor size, the majority of PSNH patients were initially offered observation, compared to TAMC where most patients were initially offered surgery.

Socioeconomic determinants impact quality of life at vestibular schwannoma diagnosis

BACKGROUND

Socioeconomic variables including race, education, and income have been shown to affect vestibular schwannoma incidence, treatment, and outcomes. We sought to determine the impact of socioeconomic factors on quality of life at the time of vestibular schwannoma diagnosis.

METHODS

Retrospective cohort study conducted at a tertiary academic center. All patients evaluated for vestibular schwannoma from March 1, 2010 to December 31, 2021 who completed at least one Penn Acoustic Neuroma Quality of Life (PANQOL) questionnaire at presentation or prior to any intervention were included. PANQOL scores were compared across income quintiles, racial groups, and health insurance categories.

RESULTS

Two-hundred and ninety-six patients who had non-missing information on variables of interest were included. Compared to White/Caucasian patients (84.5 %), Black/African American patients (4.7 %) had significantly lower PANQOL total scores (b = -12.8[-21.7, -4.0], p = 0.005). Compared to patients with Commercial insurance (53 %), patients who were Uninsured/ Self-pay (1.7 %) had significantly lower PANQOL total scores (b = -16.7[-31.4, -1.9], p = 0.027). Patients in higher income quintiles had significantly higher PANQOL total scores (b = 11.7[3.9, 19.5], p = 0.004 comparing highest income quintile to lowest). After controlling for potential confounders, income quintile (b = 9.6[1.3, 17.9], p = 0.023 comparing highest quintile to lowest) and insurance (b = -17.0[-31.9, -21], p = 0.025 comparing Uninsured/Self-pay to Commercial insurance) remained predictors of total PANQOL score.

CONCLUSIONS

Socioeconomic factors including race, health insurance, and income appear to contribute to quality of life at the time of vestibular schwannoma diagnosis. These variables are interrelated and the effects of race may be mediated in part by differences in income and health insurance coverage.

Life Expectancy After Diagnosis of a Vestibular Schwannoma in Patients 70 Years and Older

Importance

Over the past decades, the number of patients, especially in the older adult patient group, diagnosed with vestibular schwannoma (VS) has increased. Assuming that older adult patients have more comorbidities, a longer recovery period after surgery, a higher rate of surgical complications, and a higher mortality rate after VS surgery, a treatment strategy for this group of patients is warranted, based on clinical evidence on postsurgical survival.

Objective

To evaluate the survival after diagnosis of a VS in patients 70 years and older, treated with either observation or surgery, and to compare these findings with the life span of an age-matched background population in Denmark.

Design, Setting, and Participants

This was a retrospective cohort study of 624 patients 70 years and older diagnosed with VS in Denmark from 1976 to 2016. Since 1976, all patients with a VS have been registered in a national database, which contains 3637 patients. Of the included patients in this study, 477 were treated conservatively with the "wait-and-scan" strategy, and 147 were treated surgically with removal of the tumor. The survival of the patients was compared with a matched background population in Denmark. Data analysis was performed from January 1976 to January 2017.

Exposures

Surgery, radiotherapy, or none.

Main Outcomes and Measures

The main outcome was survival among the patients and compared with the matched background population.

Results

A total of 624 patients were included (317 female patients [50.8%] and 307 male patients [49.2%]). The mean (SD) survival in the observed patients was 9.2 (4.7) years after diagnosis, whereas for the background population, the expected survival was 11 years from the mean age at diagnosis. For the surgically treated patients, the mean (SD) survival was 11.8 (6.6) years, and expected survival was 11 years for the matched background population. The mean (SD) survival was 10.7 (5.5) years in female patients and 8.9 (5.0) years in male patients. There was no significant difference in survival between treatment modalities, irrespective of tumor size.

Conclusions and Relevance

In this cohort study, survival after diagnosis of a VS in patients 70 years and older was similar in the surgical group compared with the age-matched background population. In the wait-and-scan group, the survival after diagnosis was marginally shorter, which may be associated with increased comorbidity.

Skull Base Tumors

OBJECTIVE

This article reviews the presenting features, molecular characteristics, diagnosis, and management of selected skull base tumors, including meningiomas, vestibular schwannomas, pituitary neuroendocrine tumors, craniopharyngiomas, chordomas, ecchordosis physaliphora, chondrosarcomas, esthesioneuroblastomas, and paragangliomas.

LATEST DEVELOPMENTS

Skull base tumors pose a management challenge given their complex location and, as a result, the tumors and treatment can result in significant morbidity. In most cases, surgery, radiation therapy, or both yield high rates of disease control, but the use of these therapies may be limited by the surgical accessibility of these tumors and their proximity to critical structures. The World Health Organization classification of pituitary neuroendocrine tumors was updated in 2022. Scientific advances have led to an enhanced understanding of the genetic drivers of many types of skull base tumors and have revealed several potentially targetable genetic alterations. This information is being leveraged in the design of ongoing clinical trials, with the hope of rendering these challenging tumors treatable through less invasive and morbid measures.

ESSENTIAL POINTS

Tumors involving the skull base are heterogeneous and may arise from bony structures, cranial nerves, the meninges, the sinonasal tract, the pituitary gland, or embryonic tissues. Treatment often requires a multidisciplinary approach, with participation from radiation oncologists, medical oncologists, neuro-oncologists, and surgical specialists, including neurosurgeons, otolaryngologists, and head and neck surgeons. Treatment has largely centered around surgical resection, when feasible, and the use of first-line or salvage radiation therapy, with chemotherapy, targeted therapy, or both considered in selected settings. Our growing understanding of the molecular drivers of these diseases may facilitate future expansion of pharmacologic options to treat skull base tumors.

Vestibular Schwannoma Stereotactic Radiosurgery in Octogenarians: Case Series

BACKGROUND AND OBJECTIVES

The management of octogenarians with vestibular schwannomas (VS) has received little attention. However, with the increase in octogenarian population, more effort is needed to clarify the value of stereotactic radiosurgery (SRS) in this population. The aim of this study was to evaluate the safety and efficacy of SRS in this patient age group.

METHODS

A retrospective study of 62 patients aged 80 years or older who underwent single-session SRS for symptomatic VS during a 35-year interval was performed. The median patient age was 82 years, and 61.3% were male. SRS was performed as planned adjuvant management or for delayed progression after prior partial resection in 5 patients.

RESULTS

SRS resulted in a 5-year tumor control rate of 95.6% with a 4.8% risk of adverse radiation effects (ARE). Tumor control was unrelated to patient age, tumor volume, Koos grade, sex, SRS margin dose, or prior surgical management. Four patients underwent additional management including 1 patient with symptomatic progression requiring surgical resection, 2 patients with symptomatic hydrocephalus requiring cerebrospinal fluid diversion, and 1 patient whose tumor-related cyst required delayed cyst aspiration. Three patients developed ARE, including 1 patient with permanent facial weakness (House-Brackmann grade II), 1 who developed trigeminal neuropathy, and 1 who had worsening gait disorder. Six patients had serviceable hearing preservation before SRS, and 2 maintained serviceable hearing preservation after 4 years. A total of 44 (71%) patients died at an interval ranging from 6 to 244 months after SRS.

CONCLUSION

SRS resulted in tumor and symptom control in most octogenarian patients with VS.

Joint Vestibular Schwannoma Enlargement Prediction and Segmentation Using a Deep Multi-task Model

OBJECTIVE

To develop a deep-learning-based multi-task (DMT) model for joint tumor enlargement prediction (TEP) and automatic tumor segmentation (TS) for vestibular schwannoma (VS) patients using their initial diagnostic contrast-enhanced T1-weighted (ceT1) magnetic resonance images (MRIs).

METHODS

Initial ceT1 MRIs for VS patients meeting the inclusion/exclusion criteria of this study were retrospectively collected. VSs on the initial MRIs and their first follow-up scans were manually contoured. Tumor volume and enlargement ratio were measured based on expert contours. A DMT model was constructed for jointly TS and TEP. The manually segmented VS volume on the initial scan and the tumor enlargement label (≥20% volumetric growth) were used as the ground truth for training and evaluating the TS and TEP modules, respectively.

RESULTS

We performed 5-fold cross-validation with the eligible patients (n = 103). Median segmentation dice coefficient, prediction sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were measured and achieved the following values: 84.20%, 0.68, 0.78, 0.72, and 0.77, respectively. The segmentation result is significantly better than the separate TS network (dice coefficient of 83.13%, p = 0.03) and marginally lower than the state-of-the-art segmentation model nnU-Net (dice coefficient of 86.45%, p = 0.16). The TEP performance is significantly better than the single-task prediction model (AUC = 0.60, p = 0.01) and marginally better than a radiomics-based prediction model (AUC = 0.70, p = 0.17).

CONCLUSION

The proposed DMT model is of higher learning efficiency and achieves promising performance on TEP and TS. The proposed technology has the potential to improve VS patient management.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2754-2760, 2023.

Socioeconomic Disparities in the Pursuit of Care at a High-Volume Institution for Surgical Resection of Vestibular Schwannomas

OBJECTIVE

Increased institutional surgical resection case volume for vestibular schwannomas (VSs) has been associated with improved patient outcomes, including reduced risk of prolonged hospital stay and readmission. Socioeconomic disparities in the pursuit of care at these high-volume institutions remain unknown.

STUDY DESIGN

Retrospective cohort epidemiological study.

SETTING

National Cancer Database, a hospital-based registry of over 1,500 facilities in the United States.

PATIENTS

Adult VS patients (age, >18 years) treated surgically.

INTERVENTIONS

High- versus low-volume facilities, defined using a facility case volume threshold of 25 cases per year. A risk-adjusted restricted cubic spline model was previously used to identify this risk threshold beyond which the incremental benefit of increasing case volume began to plateau.

MAIN OUTCOME MEASURES

Sociodemographic factors, including race, ethnicity, income, insurance status, and rurality. Multivariable analyses were adjusted for patient and tumor characteristics, including age, sex, Charlson-Deyo score, and tumor size.

RESULTS

A totoal of 10,048 patients were identified (median [interquartile range] age = 51 [41-60] years, 54% female, 87% Caucasian). Patients with Spanish/Hispanic ethnicity (OR = 0.71, 95% confidence interval [CI] = 0.52-0.96), income below median (OR = 0.63, 95% CI = 0.55-0.73]), and Medicare, Medicaid, or other government insurance versus private insurance (OR = 0.63, 95% CI = 0.53-0.74) had reduced odds of treatment at a high-volume facility. Further sensitivity analyses in which facility volume was operationalized continuously reinforced direction and significance of these associations.

CONCLUSIONS

Socioeconomic disparities exist in the propensity for VS patients to be treated at a high-volume facility. Further work is needed to understand the nature of these associations and whether interventions can be designed to mitigate them.

Subclassification of the Koos grade 2 vestibular schwannoma into 2a and 2b for individualized patient care: a validity and reliability study

OBJECTIVE

Vestibular schwannoma (VS) growth of ≥2 mm during serial MRI observation, irrespective of size, is the benchmark for treatment initiation in almost all centers. Although the probability of less optimal outcomes significantly increases in VS closer to the brainstem, early intervention does not improve long-term quality of life. Moving beyond the recommendation of definitive treatment for all VS after detected growth, we subclassified Koos 2 tumors based on extrameatal extension and relation to the brainstem. The aim of the current study was to evaluate the Koos 2 subclassification's validity and the inter-and intra-rater reliability of the entire Koos classification.

METHODS

Six experts, including neurosurgeons, otorhinolaryngologists and radiologists from two tertiary referral centers, classified 43 VS MRI scans. Validity of the Koos 2 subclassification was evaluated by the percentage agreement against the multidisciplinary skull base tumor board management advice. Inter- and intra-rater reliability were calculated using the intraclass correlation coefficient (ICC).

RESULTS

Validity was almost perfect in Koos 2a VSs with a 100% agreement and 87.5% agreement for Koos 2b. Inter-rater reliability for all Koos grades was significantly excellent (ICC 0.91; 95%CI 0.866 to 0.944, p= <0.001). Five raters had an excellent intra-rater reliability (ICC > 0.90; p= <0.01) and one rater had a good intra-rater reliability (ICC 0.88; 95% CI 0.742 to 0.949).

CONCLUSIONS

Although multiple factors influence decision-making, the classification of Koos 2a and 2b with excellent inter- and intra-rater reliability, can aid in recommending treatment initiation, moving beyond detected tumor growth, aiming to optimize patient centered care.

Impact of Demographics and Clinical Features on Initial Treatment Pathway for Vestibular Schwannoma

OBJECTIVE

To identify demographic and clinical features impacting initial treatment pathway for vestibular schwannoma.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care academic medical center.

PATIENTS

Patients diagnosed with vestibular schwannoma between 2009 and 2019.

INTERVENTIONS

Observation, stereotactic radiosurgery, or microsurgical resection.

MAIN OUTCOME MEASURES

χ 2 Test, one-way analysis of variance, and multivariate logistic regression were used to correlate demographic and clinical factors with initial treatment pathway for 197 newly diagnosed vestibular schwannoma patients.

RESULTS

Among 197 patients, 93 (47%) were initially treated with observation, 60 (30%) with stereotactic radiation (Gamma Knife) and 44 (22%) with surgical resection. Age univariately had no statistically significant impact on initial pathway, but those undergoing surgery trended toward a younger demographic (49.1 yr [surgery] versus 57.2 yr [observation] versus 59.0 yr [Gamma Knife]). Men were more likely to be initially observed than women ( p = 0.04). Patients initially observed were more likely to have a lower Koos classification ( p < 0.001) and have better tumor-ear hearing ( p = 0.03). Only 34.4% of patients living outside the local geographic region were initially observed compared with 53.0% living locally ( p = 0.055). Surgeon correlated with initial treatment ( p = 0.04) but did not maintain significance when adjusting for hearing level or tumor size. A multiple linear regression model found age, maximum tumor diameter, and Koos class to correlate with initial treatment pathway ( p < 0.0001, r2 = 0.42).

CONCLUSION

Initial treatment pathway for newly diagnosed vestibular schwannoma is impacted by demographic factors such as age, sex, and geographic proximity to the medical center. Clinical features including hearing level and tumor size also correlated with initial treatment modality.

Factors Influencing Personalized Management of Vestibular Schwannoma: A Systematic Review

Management of vestibular schwannoma (VS) is a complex process aimed at identifying a clinical indication for fractionated stereotactic radiotherapy (sRT) or microsurgical resection or wait and scan (WS). The aim of the review was to clarify which patient and tumor parameters may lead to different therapeutic choices, with a view to a personalized VS approach. A systematic review according to Preferred Reporting Items for Systematic Review and Meta-Analysis criteria was conducted between February and March 2022. The authors defined six parameters that seemed to influence decision-making in VS management: 1-incidental VS; 2-tumor size; 3-tumor regrowth after sRT; 4-subtotal resection; 5-patients' age; 6-symptoms. The initial search yielded 3532 articles, and finally, 812 articles were included. Through a qualitative synthesis of the included studies, management strategies were evaluated and discussed. An individualized proposal of procedures is preferable as compared to a single gold-standard approach in VS decision-making. The most significant factors that need to be considered when dealing with a VS diagnosis are age, tumor size and hearing preservation issues.

Vestibular Schwannomas in Young Patients: A 12-Year Experience in a Single Center

OBJECTIVE

This study evaluated the characteristics of vestibular schwannomas (VS) in young patients, including clinical features, treatment, prognosis, and histopathologic characteristics.

METHODS

We retrospectively reviewed medical records and follow-up data for 36 pediatric patients <21 years of age who were surgically treated for VS in the Chinese PLA General Hospital between 2008 and 2019.

RESULTS

Mean patient age was 17.4 years. Mean tumor size was 2.8 cm. Hearing loss (n = 32, 88.9%) and tinnitus (n = 20, 55.6%) were the most common symptoms. Ten patients (27.8%) had impaired facial nerve function after surgery. Gross total resection (GTR) was achieved in 26 cases (72.2%). The median tumor Ki-67 level was 5%. Tumor size was related to incomplete tumor resection (odds ratio, 0.2; 95% confidence interval, 0.1-0.9) and postoperative facial nerve dysfunction (odds ratio, 24.9; 95% confidence interval, 1.2-539.1). Tumor size was nonlinearly associated with prognosis and 2.2 cm corresponded to the inflection point at which the probability of tumor remnant and postoperative facial nerve dysfunction significantly increased. The GTR and low Ki-67 groups achieved better 3-year tumor control rate. Histopathologic findings confirmed the presence of cellular schwannoma subtype in young patients.

CONCLUSIONS

Tumor size is an important factor affecting the prognosis of VS in young patients. For large VS, surgical treatment should be the first choice, rather than wait-and-scan. VS in young patients shows high tumor proliferation and a tendency to relapse. The cellular schwannoma subtype requires special attention; an accurate histopathologic diagnosis is necessary for young patients with VS, and a closer follow-up strategy should be adopted for cellular VS.

Predictors of Postoperative Complications in Vestibular Schwannoma Surgery-A Population-Based Study

OBJECTIVE

To investigate preoperative patient demographics and comorbidities in relation with postsurgical complications following vestibular schwannoma surgery.

STUDY DESIGN

Retrospective population-based cohort study.

SETTING

All hospitals in the Canadian province of Ontario.

PATIENTS

This study includes 1,456 patients who underwent vestibular schwannoma surgery from April 1, 2002 to March 31, 2018 in Ontario, Canada.

INTERVENTION/OUTCOME MEASURES

For all surgical patients, the demographic data, preoperative comorbidities, and postoperative complications were evaluated. Postoperative complications were examined immediately following surgery in the hospital as well as 1 year following the hospital discharge.

RESULTS

The most common comorbidities in this cohort were hypertension (30.22%), diabetes (9.48%), asthma (13.53%), and chronic obstructive pulmonary disease (6.73%). Diabetes was the most impactful comorbidity and was associated with higher risk of myocardial infarction (RR = 4.58, p < 0.01), pneumonia (RR = 1.80, p = 0.02), dysphagia (RR = 1.58, p < 0.01), and meningitis (RR = 3.62, p < 0.01). Analysis of surgical approaches revealed that the translabyrinthine approach, compared with the open craniotomy approach, was negatively associated with postoperative complications including pneumonia (RR = 0.43, p < 0.01), urinary tract infection (RR = 0.55, p = 0.01), dysphagia (RR = 0.66, p < 0.01), and readmission (RR = 0.45, p < 0.01).

CONCLUSION

This study examines patient demographics, preoperative comorbidities, and postoperative complications in patients who have undergone vestibular schwannoma surgery. The results highlight associations between patient characteristics and postoperative outcomes that can aid in preoperative decision-making and counselling.