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Journal of Radiosurgery and SBRT 2019Vestibular schwannomas (VS) are benign tumors with a slow growth rate. There exists controversy regarding whether patients should receive upfront observation, SRS, FSRT,...
INTRODUCTION
Vestibular schwannomas (VS) are benign tumors with a slow growth rate. There exists controversy regarding whether patients should receive upfront observation, SRS, FSRT, or surgery at the time of diagnosis. For patients declining resection, this systematic review evaluates the risks and benefits between observation and SRS upon diagnosis of VS.
METHODS
Published studies on VS (including acoustic neuromas) were systematically reviewed for clinical series including patients with newly/recently diagnosed unilateral VS. Studies that included patients with previous treatment for the VS or focused on patients with neurofibromatosis (or other genetic conditions) were excluded. Review articles and systematic reviews were excluded but reviewed for relevant references that would otherwise meet search criteria.
RESULTS
Most patients electing observation underwent their first surveillance scan 6 months after initial diagnosis, then annually or every-other-year thereafter. Follow up was similar for patients receiving radiosurgery. The follow up period varied between studies as not all studies published at a specific time point. Observation alone conferred a radiographic tumor control rate of 65% and serviceable hearing in 71.3% at by the end of the follow up period in the reviewed studies, and 34% of patients initially opting for observation went on to ultimately elect for treatment. Initial radiosurgery resulted in a tumor control rate of 97% and serviceable hearing rate of 73.8% at by the end of the follow up period. Radiosurgery resulted in improved tumor control at the end of the follow up period (p < 0.0001), and serviceable hearing did not statistically differ (p = 0.69). There is an early risk of progressive hearing decline on patients who chose initial observation.
CONCLUSION
Based on the available published data, observation after initial diagnosis is appropriate for many patients with VS without symptomatic brainstem compression. However, initial observation does risk early progressive hearing dysfunction and patients with serviceable hearing at diagnosis may benefit from early therapy. Long term follow up is critical, and an algorithm to better risk-stratify patients with newly diagnosed VS is underway.
PubMed: 31641546
DOI: No ID Found -
The Journal of International Advanced... Aug 2018In light of missing systematic reviews in the literature, the objective of this paper is to present the contemporary knowledge on the molecular biology of vestibular... (Meta-Analysis)
Meta-Analysis
In light of missing systematic reviews in the literature, the objective of this paper is to present the contemporary knowledge on the molecular biology of vestibular schwannomas (VS), based on a systematic literature search. In addition, current and prospected medical therapy based on molecular biology is addressed. A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The systematic search was performed in the Pubmed and Embase databases. The following were the words searched: acoustic neuroma/vestibular schwannoma, molecular biology, gene, and microRNA. Specific inclusion and exclusion criteria were determined prior to search. The systematic search rendered 486 articles, ultimately yielding 69 included articles, whereas 35 were from relevant references. The occurrence of at least one mutation in the merlin gene was reported to range between 54% and 76%, whereas the loss of heterozygosity (LOH) corresponding to chromosome 22 occurs in 25% to 83% of sporadic VS. Global gene expression studies indicate that a number of genes other than merlin are at play. No high-level methylation of the merlin gene has been found. Several miRNAs are deregulated in tumor tissue, among others let-7d, miR-221, and miR-21. The acquired knowledge on molecular biology has led to several clinical implementations. Lack of the tumor suppressor merlin plays a principal role in the development of VS. Existing knowledge on the molecular biology has led to the first attempts of targeted medical treatment to prevent tumor growth. Future research is likely to introduce potential imaging markers with prognostic value and new targets for medical therapy.
Topics: Chromosomes, Human, Pair 22; DNA Methylation; Gene Expression; Humans; Loss of Heterozygosity; MicroRNAs; Molecular Biology; Mutation; Neuroma, Acoustic; Signal Transduction
PubMed: 30100540
DOI: 10.5152/iao.2018.4929 -
Brazilian Journal of Otorhinolaryngology 2019Intralabyrinthine schwannoma is a rare, benign tumor that affects the most terminal portions of the vestibular and cochlear nerves. This tumor can be classified into 10...
INTRODUCTION
Intralabyrinthine schwannoma is a rare, benign tumor that affects the most terminal portions of the vestibular and cochlear nerves. This tumor can be classified into 10 subtypes, according to its inner ear location.
OBJECTIVE
To carry out a comprehensive review of the most frequent auditory manifestations secondary to the intralabyrinthine schwannoma, describing the possible underlying pathophysiological mechanisms.
METHODS
Systematic review of the literature until October 2017 using the PubMed, Web of Science and Scopus databases. The inclusion criteria were clinical manifestations of the intralabyrinthine schwannoma. Three researchers independently assessed the articles and extracted relevant information. The description of a case of an intravestibular subtype intralabyrinthine schwannoma with multiple forms of clinical presentations was used as an example.
RESULTS
Twenty-seven studies met our inclusion criteria. The most common intralabyrinthine schwannoma subtype was the intracochlear, followed by the intravestibular type. All the cases demonstrated hearing loss, usually progressive hearing loss.
CONCLUSION
The diagnosis of intralabyrinthine schwannomas is based on high-resolution magnetic resonance imaging and should be included in the differential diagnosis of patients with vestibulocochlear complaints. Although there are approximately 600 cases in the literature, we still lack a detailed description of the clinical evolution of the patients, correlating it with MRI findings of temporal bones and tumor subtype.
Topics: Adult; Audiometry; Disease Progression; Female; Hearing Loss; Humans; Labyrinth Diseases; Magnetic Resonance Imaging; Neuroma, Acoustic
PubMed: 29980446
DOI: 10.1016/j.bjorl.2018.05.007 -
Otology & Neurotology : Official... Mar 2018To determine the long-term hearing preservation rate for spontaneous vestibular schwannoma treated by primary radiotherapy.
OBJECTIVE
To determine the long-term hearing preservation rate for spontaneous vestibular schwannoma treated by primary radiotherapy.
DATA SOURCES
The MEDLINE/PubMed, Web of Science, Cochrane Reviews, and EMBASE databases were searched using a comprehensive Boolean keyword search developed in conjunction with a scientific librarian. English language papers published from 2000 to 2016 were evaluated.
STUDY SELECTION
Inclusion criteria: full articles, pretreatment and posttreatment audiograms or audiogram based scoring system, vestibular schwannoma only tumor type, reported time to follow-up, published after 1999, use of either Gamma Knife or linear accelerator radiotherapy.
EXCLUSION CRITERIA
case report or series with fewer than five cases, inadequate audiometric data, inadequate time to follow-up, neurofibromatosis type 2 exceeding 10% of study population, previous treatment exceeding 10% of study population, repeat datasets, use of proton beam therapy, and non-English language.
DATA EXTRACTION
Two reviewers independently analyzed papers for inclusion. Class A/B, 1/2 hearing was defined as either pure tone average less than or equal to 50 db with speech discrimination score more than or equal to 50%, American Academy of Otolaryngology-Head & Neck Surgery (AAO-HNS) Hearing Class A or B, or Gardner-Robertson Grade I or II. Aggregate data were used when individual data were not specified.
DATA SYNTHESIS
Means were compared with student t test.
CONCLUSIONS
Forty seven articles containing a total of 2,195 patients with preserved Class A/B, 1/2 hearing were identified for analysis. The aggregate crude hearing preservation rate was 58% at an average reporting time of 46.6 months after radiotherapy treatment. Analysis of time-based reporting shows a clear trend of decreased hearing preservation extending to 10-year follow-up. This data encourages a future long-term controlled trial.
Topics: Adult; Female; Hearing; Hearing Loss; Humans; Male; Middle Aged; Neuroma, Acoustic; Radiosurgery
PubMed: 29342035
DOI: 10.1097/MAO.0000000000001672 -
Asian Journal of Neurosurgery 2017This systematic review wasdesigned to compare the complications of acoustic neuroma surgery via the suboccipital retrosigmoid approach in the sitting versus lateral... (Review)
Review
This systematic review wasdesigned to compare the complications of acoustic neuroma surgery via the suboccipital retrosigmoid approach in the sitting versus lateral positions. Searches for randomized trials and observational studies about the complications of acoustic neuroma surgery were performed in five medical databases (though October 2015) including PubMed, MEDLINE (In-Process and Other Non-Indexed Citations), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL) and PsycINFO. Primary outcomes in this study were venous air emboli, neuropsychological defects, CSF leak, facial and abducens nerves palsy, postoperative deafness, hydrocephalus and mortality. Secondary outcomes were total tumor removal, facial and cochlear nerves preservation and ataxia. 843 abstracts and titles were reviewed and 10 studies (two non-randomized comparative studies and 8 non-comparative case series) were included for data extraction. Because of the heterogeneity of the studies, small number of participants and methodological shortcomings, findings were evaluated qualitatively. No impressive advantage was found in surgical or neurological outcomes for use of the sitting or lateral positions in patients with acoustic neuroma surgery. According to the available evidence, it seems that both sitting and lateral positions can be used with an equivalent safety for acoustic neuroma surgery via the retrosigmoid suboccipital approach. There seems a clear need for comparative studies to compare harms and other outcomes for these two positions.
PubMed: 28761510
DOI: 10.4103/1793-5482.185069 -
Acta Neurochirurgica Jun 2017Repeated controlled studies have revealed that stereotactic radiosurgery is better than microsurgery for patients with vestibular schwannoma (VS) <3 cm in need of... (Comparative Study)
Comparative Study Review
OBJECTIVE
Repeated controlled studies have revealed that stereotactic radiosurgery is better than microsurgery for patients with vestibular schwannoma (VS) <3 cm in need of intervention. In this systematic review we aimed to compare results from single-fraction stereotactic radiosurgery (SRS) to fractionated stereotactic radiotherapy (FSRT) for patients with VS.
DATA SOURCES AND ELIGIBILITY CRITERIA
We systematically searched MEDLINE, Web of Science, Embase and Cochrane and screened relevant articles for references. Publications from 1995 through 2014 with a minimum of 50 adult (>18 years) patients with unilateral VS, followed for a median of >5 years, were eligible for inclusion. After screening titles and abstracts of the 1094 identified articles and systematically reviewing 98 of these articles, 19 were included.
INTERVENTION
Patients with unilateral VS treated with radiosurgery were compared to patients treated with fractionated stereotactic radiotherapy.
RESULTS
No randomized controlled trial (RCT) was identified. None of the identified controlled studies comparing SRS with FSRT were eligible according to the inclusion criteria. Nineteen case series on SRS (n = 17) and FSRT (n = 2) were included in the systematic review. Loss of tumor control necessitating a new VS-targeted intervention was found in an average of 5.0% of the patients treated with SRS and in 4.8% treated with FSRT. Mean deterioration ratio for patients with serviceable hearing before treatment was 49% for SRS and 45% for FSRT, respectively. The risk for facial nerve deterioration was 3.6% for SRS and 11.2% for FSRT and for trigeminal nerve deterioration 6.0% for SRS and 8.4% for FSRT. Since these results were obtained from case series, a regular meta-analysis was not attempted.
CONCLUSION
SRS and FSRT are both noninvasive treatment alternatives for patients with VS with low rates of treatment failure in need of rescue therapy. In this selection of patients, the progression-free survival rates were on the order of 92-100% for both treatment options. There is a lack of high-quality studies comparing radiation therapy alternatives for patients with VS. Finally, 19 articles reported long-term tumor control after SRS, while only 2 articles reported long-term FSRT results, making effect estimates more uncertain for FSRT.
Topics: Adult; Aged; Disease-Free Survival; Dose Fractionation, Radiation; Facial Nerve; Female; Humans; Male; Microsurgery; Neuroma, Acoustic; Postoperative Complications; Radiosurgery; Trigeminal Nerve
PubMed: 28409393
DOI: 10.1007/s00701-017-3164-6 -
International Journal of Occupational... Feb 2017Results of epidemiological studies on the association between use of mobile phone and brain cancer are ambiguous, as well as the results of 5 meta-analysis studies... (Meta-Analysis)
Meta-Analysis Review
Results of epidemiological studies on the association between use of mobile phone and brain cancer are ambiguous, as well as the results of 5 meta-analysis studies published to date. Since the last meta-analysis (2009), new case-control studies have been published, which theoretically could affect the conclusions on this relationship. Therefore, we decided to perform a new meta-analysis. We conducted a systematic review of multiple electronic data bases for relevant publications. The inclusion criteria were: original papers, case-control studies, published till the end of March 2014, measures of association (point estimates as odds ratio and confidence interval of the effect measured), data on individual exposure. Twenty four studies (26 846 cases, 50 013 controls) were included into the meta-analysis. A significantly higher risk of an intracranial tumor (all types) was noted for the period of mobile phone use over 10 years (odds ratio (OR) = 1.324, 95% confidence interval (CI): 1.028-1.704), and for the ipsilateral location (OR = 1.249, 95% CI: 1.022-1.526). The results support the hypothesis that long-term use of mobile phone increases risk of intracranial tumors, especially in the case of ipsilateral exposure. Further studies are needed to confirm this relationship. Int J Occup Med Environ Health 2017;30(1)27-43.
Topics: Brain Neoplasms; Case-Control Studies; Cell Phone; Electromagnetic Fields; Environmental Exposure; Humans; Salivary Gland Neoplasms
PubMed: 28220905
DOI: 10.13075/ijomeh.1896.00802 -
BioMed Research International 2016. Vestibular schwannomas (VS) are benign tumours of the vestibular nerve and can lead to hearing loss, tinnitus, vertigo, facial palsy, and brainstem compression.... (Meta-Analysis)
Meta-Analysis
. Vestibular schwannomas (VS) are benign tumours of the vestibular nerve and can lead to hearing loss, tinnitus, vertigo, facial palsy, and brainstem compression. Audiovestibular diagnostic tests are essential for detection and treatment planning. . Medline was used to perform a systematic literature review with regard to how audiovestibular test parameters correlate with symptoms, tumour size, and tumour location. . The auditory brainstem response can be used to diagnose retrocochlear lesions caused by VS. Since hearing loss correlates poorly with tumour size, a retrocochlear lesion is probably not the only cause for hearing loss. Also cochlear mechanisms seem to play a role. This can be revealed by abnormal otoacoustic emissions, despite normal ABR and new MRI techniques which have demonstrated endolymphatic hydrops of the inner ear. Caloric and head impulse tests show frequency specific dynamics and vestibular evoked myogenic potentials may help to identify the location of the tumour regarding the involved nerve parts. . In order to preserve audiovestibular function in VS, it is important to stop the growth of the tumour and to avoid degenerative changes in the inner ear. A detailed neurotological workup helps to diagnose VS of all sizes and can also provide useful prognostic information.
Topics: Evoked Potentials, Auditory, Brain Stem; Hearing Loss; Humans; Magnetic Resonance Imaging; Neuroma, Acoustic; Vertigo; Vestibular Function Tests; Vestibule, Labyrinth
PubMed: 27747231
DOI: 10.1155/2016/4980562 -
Yonsei Medical Journal May 2016Many epidemiological studies have investigated environmental risk factors for the development of acoustic neuroma. However, these results are controversial. We conducted... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Many epidemiological studies have investigated environmental risk factors for the development of acoustic neuroma. However, these results are controversial. We conducted a meta-analysis of case-control studies to identify any potential relationship between history of noise exposure, smoking, allergic diseases, and risk of acoustic neuroma.
MATERIALS AND METHODS
We searched PubMed to identify relevant articles. Two researchers evaluated the eligibility and extracted the data independently.
RESULTS
Eleven case-control studies were included in our meta-analysis. Acoustic neuroma was found to be associated with leisure noise exposure [odds ratio (OR)=1.33, 95% confidence interval (CI): 1.05-1.68], but not with occupational noise exposure and ever noise exposure (OR=1.20, 95% CI: 0.84-1.72 and OR=1.15, 95% CI: 0.80-1.65). The OR of acoustic neuroma for ever (versus never) smoking was 0.53 (95% CI: 0.30-0.94), while the subgroup analysis indicated ORs of 0.95 (95% CI: 0.81-1.10) and 0.49 (95% CI: 0.41-0.59) for ex-smoker and current smoker respectively. The ORs for asthma, eczema, and seasonal rhinitis were 0.98 (95% CI: 0.80-1.18), 0.91 (95% CI: 0.76-1.09), and 1.52 (95% CI: 0.90-2.54), respectively.
CONCLUSION
Our meta-analysis is suggestive of an elevated risk of acoustic neuroma among individuals who were ever exposed to leisure noise, but not to occupational noise. Our study also indicated a lower acoustic neuroma risk among ever and current cigarette smokers than never smokers, while there was no significant relationship for ex-smokers. No significant associations were found between acoustic neuroma and history of any allergic diseases, such as asthma, eczema, and seasonal rhinitis.
Topics: Adult; Asthma; Environmental Exposure; Female; Humans; Hypersensitivity; Leisure Activities; Neuroma, Acoustic; Noise; Occupational Exposure; Risk Factors; Smoking
PubMed: 26996581
DOI: 10.3349/ymj.2016.57.3.776 -
The Cochrane Database of Systematic... Dec 2014Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation... (Review)
Review
BACKGROUND
Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy.
OBJECTIVES
To assess the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014.
SELECTION CRITERIA
Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical resection or any other possible treatment or combination of treatments in patients with a cerebellopontine angle tumour up to 3 cm in diameter, presumed to be a vestibular schwannoma.
DATA COLLECTION AND ANALYSIS
We used the standard methodological procedures expected by The Cochrane Collaboration.
MAIN RESULTS
No studies met the inclusion criteria for this review.
AUTHORS' CONCLUSIONS
There is no high quality evidence in the literature from RCTs to determine whether stereotactic radiotherapy is better than microsurgical resection or observation alone for patients with a vestibular schwannoma. In the absence of such evidence, the treatment method should be chosen on an individual basis, taking into consideration the patient's preferences, clinician experience and the availability of radiotherapeutic equipment. With the growing availability of radiotherapeutic equipment, randomised controlled trials should be undertaken to evaluate the role of stereotactic radiotherapy in comparison with other treatment options.
Topics: Humans; Neuroma, Acoustic; Radiosurgery
PubMed: 25511415
DOI: 10.1002/14651858.CD009897.pub2