ABSTRACT
NF2-related schwannomatosis (NF2; previously termed neurofibromatosis type 2) is a tumor-prone disorder characterized by development of multiple schwannomas and meningiomas. The diagnostic criteria of NF2 have been regularly revised. Clinical criteria for NF2 were first formulated at the National Institutes of Health Consensus Conference in 1987 and revised in 1990. Revised criteria were also proposed by the Manchester group in 1992 and by the National Neurofibromatosis Foundation (NNFF) in 1997. The 2011 Baser criteria improved the sensitivity of diagnostic criteria, particularly for patients without bilateral vestibular schwannomas. Revisions to the Manchester criteria were published in 2019, with replacement of "glioma" by "ependymoma," removal of "neurofibroma," addition of an age limit of 70 years for development of vestibular schwannomas, and introduction of molecular criteria, which led to the most widely used criteria. In 2022, the criteria were reviewed and updated by the international committee of NF experts. In addition to changes in diagnostic criteria, the committee recommended the use of "schwannomatosis" as an umbrella term for conditions that predispose to schwannomas. Each type of schwannomatosis was classified by the gene containing the disease-causing pathogenic variant. Molecular data from NF2 patients led to further clarification of the diagnostic criteria for NF2 mosaic phenotypes. Given all these changes, the diagnostic criteria of NF2 may be confusing. Herein, to help healthcare professionals who diagnose NF2 conditions in the clinical setting, we review the historical development of diagnostic criteria.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 2 , Skin Neoplasms , Humans , Neurilemmoma/diagnosis , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatoses/diagnosis , Neurofibromatoses/history , Skin Neoplasms/diagnosis , Skin Neoplasms/pathology , History, 20th Century , History, 21st CenturyABSTRACT
Neurofibromatosis type 2 (NF2) is a rare autosomal dominant disease (frequency 1 in 25-90 000) characterized by the formation of tumors of the central nervous system due to a mutation in the NF2 gene on chromosome 22q12. Bilateral vestibular schwannomas are recognized as absolute diagnostic criteria of NF2 and occur in 95% of patients, are accompanied by hearing impairment, manifest at the age of 18-24 years. Skin manifestations can precede vestibular schwannomas for several years and predict the course of the disease: neurofibromas, cafe-au-lait macules, hypopigmented spots, recently described mesh capillary malformations. Despite the benign nature of schwannomas, they can lead to hearing loss, vestibular dysfunction, facial nerve paralysis, gait disorders, pain and convulsions, there is a risk of early death from compression of the brain stem. The probability of progressive hearing loss is partly determined by the type of mutation. We described a clinical case of NF2 in a 21-year-old patient with bilateral vestibular schwannomas without hearing loss, whose skin examination by ENT specialist revealed this disease. The importance of the presented observation is that the doctor should assume neurofibromatosis type 2 in a young patient with bilateral vestibular schwannomas. It is necessary to undertake a further examination of this patient, including: skin examination for the identification of characteristic neurofibromas and cafe-au-lait macules, consultation with an ophthalmologist, neurologist, MRI of the brain and spinal cord with contrast, genetic analysis - for timely initiation of therapy that prevents hearing loss and vestibular disorders.
Subject(s)
Hearing Loss , Neurofibromatosis 2 , Neuroma, Acoustic , Humans , Adolescent , Young Adult , Adult , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neuroma, Acoustic/complications , MutationABSTRACT
BACKGROUND: Neurofibromatosis type 2-related schwannomatosis is a genetic disease characterized by the development of bilateral vestibular schwannomas, ependymomas, meningiomas, and cataracts. Mild to profound hearing loss and tinnitus are common symptoms reported by individuals with neurofibromatosis type 2. While tinnitus is known to have a significant and negative impact on the quality of life of individuals from the general population, the impact on individuals with neurofibromatosis type 2 is unknown. Consensus regarding the selection of suitable patient-reported outcome measures for assessment could advance further research into tinnitus in neurofibromatosis type 2 patients. The purpose of this work is to achieve a consensus recommendation by the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration for patient-reported outcome measures used to evaluate quality of life in the domain of tinnitus for neurofibromatosis type 2 clinical trials. METHODS: The Response Evaluation in Neurofibromatosis and Schwannomatosis Patient-Reported Outcomes Communication Subgroup systematically evaluated patient-reported outcome measures of quality of life in the domain of tinnitus for individuals with neurofibromatosis type 2 using previously published Response Evaluation in Neurofibromatosis and Schwannomatosis rating procedures. Of the 19 identified patient-reported outcome measures, 3 measures were excluded because they were not validated as an outcome measure or could not have been used as a single outcome measure for a clinical trial. Sixteen published patient-reported outcome measures for the domain of tinnitus were scored and compared on their participant characteristics, item content, psychometric properties, and feasibility for use in clinical trials. RESULTS: The Tinnitus Functional Index was identified as the most highly rated measure for the assessment of tinnitus in populations with neurofibromatosis type 2, due to strengths in the areas of item content, psychometric properties, feasibility, and available scores. DISCUSSION: Response Evaluation in Neurofibromatosis and Schwannomatosis currently recommends the Tinnitus Functional Index for the assessment of tinnitus in neurofibromatosis type 2 clinical trials.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 2 , Skin Neoplasms , Tinnitus , Humans , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Tinnitus/diagnosis , Tinnitus/etiology , Quality of Life , Neurofibromatoses/complications , Neurofibromatoses/diagnosis , Patient Reported Outcome MeasuresABSTRACT
INTRODUCTION: Neurofibromatosis 1 and schwannomatosis are characterized by potential lifelong morbidity and life-threatening complications. To date, however, diagnostic and predictive biomarkers are an unmet need in this patient population. The inclusion of biomarker discovery correlatives in neurofibromatosis 1/schwannomatosis clinical trials enables study of low-incidence disease. The implementation of a common data model would further enhance biomarker discovery by enabling effective concatenation of data from multiple studies. METHODS: The Response Evaluation in Neurofibromatosis and Schwannomatosis biomarker working group reviewed published data on emerging trends in neurofibromatosis 1 and schwannomatosis biomarker research and developed recommendations in a series of consensus meetings. RESULTS: Liquid biopsy has emerged as a promising assay for neurofibromatosis 1/schwannomatosis biomarker discovery and validation. In addition, we review recommendations for a range of biomarkers in clinical trials, neurofibromatosis 1/schwannomatosis-specific data annotations, and common data models for data integration. CONCLUSION: These Response Evaluation in Neurofibromatosis and Schwannomatosis consensus guidelines are intended to provide best practices for the inclusion of biomarker studies in neurofibromatosis 1/schwannomatosis clinical trials, data, and sample annotation and to lay a framework for data harmonization and concatenation between trials.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 1 , Neurofibromatosis 2 , Skin Neoplasms , Humans , Neurofibromatosis 1/diagnosis , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/pathology , Neurofibromatoses/diagnosis , Neurofibromatoses/therapy , Neurofibromatoses/pathology , BiomarkersABSTRACT
Numerous successful gene-targeted therapies are arising for the treatment of a variety of rare diseases. At the same time, current treatment options for neurofibromatosis 1 and schwannomatosis are limited and do not directly address loss of gene/protein function. In addition, treatments have mostly focused on symptomatic tumors, but have failed to address multisystem involvement in these conditions. Gene-targeted therapies hold promise to address these limitations. However, despite intense interest over decades, multiple preclinical and clinical issues need to be resolved before they become a reality. The optimal approaches to gene-, mRNA-, or protein restoration and to delivery to the appropriate cell types remain elusive. Preclinical models that recapitulate manifestations of neurofibromatosis 1 and schwannomatosis need to be refined. The development of validated assays for measuring neurofibromin and merlin activity in animal and human tissues will be critical for early-stage trials, as will the selection of appropriate patients, based on their individual genotypes and risk/benefit balance. Once the safety of gene-targeted therapy for symptomatic tumors has been established, the possibility of addressing a wide range of symptoms, including non-tumor manifestations, should be explored. As preclinical efforts are underway, it will be essential to educate both clinicians and those affected by neurofibromatosis 1/schwannomatosis about the risks and benefits of gene-targeted therapy for these conditions.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 1 , Neurofibromatosis 2 , Skin Neoplasms , Animals , Humans , Neurofibromatosis 1/genetics , Neurofibromatosis 1/therapy , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatosis 2/pathology , Neurofibromatoses/genetics , Neurofibromatoses/therapy , Neurofibromatoses/diagnosis , Neurilemmoma/genetics , Neurilemmoma/therapy , Neurilemmoma/diagnosisABSTRACT
BACKGROUND/AIMS: Individuals with neurofibromatosis, including neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2)-related schwannomatosis (SWN), and other forms of SWN, often experience disease manifestations and mental health difficulties for which psychosocial interventions may help. An anonymous online survey of adults with neurofibromatosis assessed their physical, social, and emotional well-being and preferences about psychosocial interventions to inform clinical trial design. METHODS: Neurofibromatosis clinical researchers and patient representatives from the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration developed the survey. Eligibility criteria included age ≥ 18 years, self-reported diagnosis of NF1, NF2, or SWN, and ability to read and understand English. The online survey was distributed internationally by the Neurofibromatosis Registry and other neurofibromatosis foundations from June to August 2020. RESULTS: Surveys were completed by 630 adults (18-81 years of age; M = 45.5) with NF1 (78%), NF2 (14%), and SWN (8%) who were mostly White, not Hispanic/Latino, female, and from the United States. The majority (91%) reported that their neurofibromatosis symptoms had at least some impact on daily life. In the total sample, 51% endorsed a mental health diagnosis, and 27% without a diagnosis believed they had an undiagnosed mental health condition. Participants indicated that neurofibromatosis affected their emotional (44%), physical (38%), and social (35%) functioning to a high degree. Few reported ever having participated in a drug (6%) or psychosocial (7%) clinical trial, yet 68% reported they "probably" or "definitely" would want to participate in a psychosocial trial if it targeted a relevant concern. Top treatment targets were anxiety, healthier lifestyle, and daily stress. Top barriers to participating in psychosocial trials were distance to clinic, costs, and time commitment. Respondents preferred interventions delivered by clinicians via individual sessions or a combination of group and individual sessions, with limited in-person and mostly remote participation. There were no significant group differences by neurofibromatosis type in willingness to participate in psychosocial trials (p = 0.27). Regarding interest in intervention targets, adults with SWN were more likely to prefer psychosocial trials for pain support compared to those with NF1 (p < 0.001) and NF2 (p < 0.001). CONCLUSION: This study conducted the largest survey assessing physical symptoms, mental health needs, and preferences for psychosocial trials in adults with neurofibromatosis. Results indicate a high prevalence of disease manifestations, psychosocial difficulties, and untreated mental health problems in adults with neurofibromatosis and a high degree of willingness to participate in psychosocial clinical trials. Patient preferences should be considered when designing and implementing psychosocial interventions to develop the most feasible and meaningful studies.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 1 , Neurofibromatosis 2 , Skin Neoplasms , Adult , Female , Humans , United States , Adolescent , Neurofibromatoses/therapy , Neurofibromatoses/diagnosis , Neurofibromatoses/psychology , Neurilemmoma/diagnosis , Neurilemmoma/psychology , Neurilemmoma/therapy , Skin Neoplasms/diagnosis , Skin Neoplasms/psychology , Skin Neoplasms/therapy , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/psychology , Neurofibromatosis 2/therapy , Neurofibromatosis 1/diagnosis , Neurofibromatosis 1/psychology , Neurofibromatosis 1/therapy , Surveys and QuestionnairesABSTRACT
Concurrent occurrence of schwannoma and meningiomas are rare, and are found especially in association with neurofibromatosis type 2 (NF2). Occurrence of mixed tumor without the aforementioned conditions is extremely rare. We present three cases of mixed tumor in different locations, including two with NF2 and one without NF2. We analyse the relationship of mixed tumor with NF2 and its clinical implications. Presence of mixed schwannoma-meningioma should prompt screening for NF2. Thus aids in early diagnosis of unsuspected NF2 cases. We observed that irrespective of different locations, cases with NF2 showed frequent recurrence of schwannoma as compared to case who did not fit in the existing clinical criteria for NF2. Collision tumor and thereby NF2 mutations indicates the prognosis and recurrence of the tumor, thereby guides in deciding the management.
Subject(s)
Meningeal Neoplasms , Meningioma , Myoepithelioma , Neurilemmoma , Neurofibromatosis 2 , Humans , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Meningioma/complications , Meningioma/diagnosis , Meningioma/genetics , Meningeal Neoplasms/complications , Meningeal Neoplasms/diagnosis , Meningeal Neoplasms/genetics , Neurilemmoma/complications , Neurilemmoma/diagnosis , Carcinogenesis , Cell Transformation, NeoplasticABSTRACT
BACKGROUND: Facial paralysis secondary to neurofibromatosis type 2 (NF2) presents the reconstructive surgeon with unique challenges because of its pathognomonic feature of bilateral acoustic neuromas, involvement of multiple cranial nerves, use of antineoplastic agents, and management. Facial reanimation literature on managing this patient population is scant. METHODS: A comprehensive literature review was performed. All patients with NF2-related facial paralysis who presented in the past 13 years were reviewed retrospectively for type and degree of paralysis, NF2 sequelae, number of cranial nerves involved, interventional modalities, and surgical notes. RESULTS: Twelve patients with NF2-related facial paralysis were identified. All patients presented after resection of vestibular schwannoma. Mean duration of weakness before surgical intervention was 8 months. On presentation, one patient had bilateral facial weakness, 11 had multiple cranial nerve involvement, and seven were treated with antineoplastic agents. Two patients underwent gracilis free functional muscle transfer, five underwent masseteric-to-facial nerve transfer (of whom two were dually innervated with a crossfacial nerve graft), and one patient underwent depressor anguli oris myectomy. Trigeminal schwannomas did not affect reconstructive outcomes if trigeminal nerve motor function on clinical examination was normal. In addition, antineoplastic agents such as bevacizumab and temsirolimus did not affect outcomes if stopped in the perioperative period. CONCLUSIONS: Effectively managing patients with NF2-related facial paralysis necessitates understanding the progressive and systemic nature of the disease, bilateral facial nerve and multiple cranial nerve involvement, and common antineoplastic treatments. Neither antineoplastic agents nor trigeminal nerve schwannomas associated with normal examination affected outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.
Subject(s)
Antineoplastic Agents , Facial Paralysis , Neurilemmoma , Neurofibromatosis 2 , Humans , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/surgery , Facial Paralysis/etiology , Facial Paralysis/surgery , Retrospective Studies , Facial Nerve/surgery , Neurilemmoma/complications , Antineoplastic Agents/therapeutic useABSTRACT
Intracochlear schwannomas (ICS) are very rare benign tumours of the inner ear. We present histopathological proof of the extremely rare bilateral occurrence of intracochlear schwannomas with negative blood genetic testing for neurofibromatosis type 2 (NF2). Bilateral schwannomas are typically associated with the condition NF2 and this case is presumed to have either mosaicism for NF2 or sporadic development of bilateral tumours. For progressive bilateral tumour growth and associated profound hearing loss, surgical intervention via partial cochleoectomy, tumour removal, preservation of the modiolus, and simultaneous cochlear implantation with lateral wall electrode carrier with basal double electrode contacts was performed. The right side was operated on first with a 14-month gap between each side. The hearing in aided speech recognition for consonant-nucleus-consonant (CNC) phonemes in quiet improved from 57% to 83% 12 months after bilateral cochlear implantation (CI). Bilateral intracochlear schwannomas in non-NF2 patients are extremely rare but should be considered in cases of progressive bilateral hearing loss. Successful tumour removal and cochlear implantation utilizing a lateral wall electrode is possible and can achieve good hearing outcomes.
Subject(s)
Cochlear Implantation , Cochlear Implants , Neurilemmoma , Neurofibromatosis 2 , Neuroma, Acoustic , Humans , Neuroma, Acoustic/diagnosis , Neuroma, Acoustic/surgery , Neuroma, Acoustic/complications , Neurilemmoma/complications , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/surgeryABSTRACT
Schwannomatoses is a new classification unit for all the hereditary diseases caused by chromosome 22 damage followed by multiple benign neoplasms of the peripheral and central nervous system. Schwannomatosis occurs as a result of damage to different genes: NF2, SMARCB1, LZRT1, loss of heterozygosity of the long arm of chromosome 22. Nevertheless, clinical manifestations are similar. Molecular diagnostics not only confirms the diagnosis, but also predicts the course of disease. Thus, the most severe clinical manifestations are observed in patients with violation of semantic sequences and reading frame shift in exons 2-13 of the NF2 gene. A more favorable course with less number of tumors is observed in patients with somatic mosaicism. Stereotactic irradiation and surgery are the main treatment options for schwannomatosis. However, there is evidence of effective targeted therapy with bevacizumab (inhibitor of vascular endothelial growth factor). Bevacizumab is used in patients with bilateral vestibular schwannomas and high risk of hearing loss, as well as for intramedullary tumor growth control.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 2 , Humans , Bevacizumab , Vascular Endothelial Growth Factor A , Neurilemmoma/genetics , Neurilemmoma/therapy , Neurofibromatoses/genetics , Neurofibromatoses/therapy , Neurofibromatoses/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatosis 2/therapy , Neurofibromatosis 2/diagnosisABSTRACT
PURPOSE OF REVIEW: In 2022, an international consensus recommendation revised the nomenclature for neurofibromatosis type 2 ( NF2 ) and Schwannomatosis (SWN), now grouped under the umbrella term Schwannomatosis, and defined new diagnostic criteria. RECENT FINDINGS: This review describes the molecular criteria for diagnosis of schwannomatosis and the subsequent diagnosis strategy, while setting out the most recent advances in our understanding of the natural history, pathology, molecular biology and treatment of schwannomatosis-associated tumors, including schwannomas, meningiomas and ependymomas. SUMMARY: Somatic mutation screening should become a new standard for the diagnosis of NF2 -, LTZTR1 -, SMARCB1 - and 22q-schwannomatosis to discriminate those conditions. Constitutional events in NF2 -Schwannomatosis have a major influence on disease severity and justifiably motivate ongoing efforts on gene replacement therapy research. On the other hand, underlying mechanisms of disease severity and associated pain remain largely unknown in non- NF2 -SWN and independent of germline mutation. Research efforts therefore focus on pain relief in ongoing trials and the discovery of new molecular mechanisms underlying schwannoma tumorigenesis/pain/neuropathies.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 2 , Skin Neoplasms , Humans , Neurilemmoma/diagnosis , Neurilemmoma/genetics , Neurilemmoma/therapy , Neurofibromatoses/diagnosis , Neurofibromatoses/genetics , Neurofibromatoses/therapy , Skin Neoplasms/diagnosis , Skin Neoplasms/genetics , Skin Neoplasms/therapy , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatosis 2/therapy , PainABSTRACT
Schwannomas are benign capsular tumors originating from Schwann cells. Although the majority are sporadic, they also occur within tumor predisposition syndromes, such as neurofibromatosis type 2, schwannomatosis, and Carney complex. Since the 5th edition of the World Health Organization(WHO)Classification of Tumors of the Central Nervous System was published, the description of grades has changed from Roman numerals to Arabic numerals. However, as in the 4th edition, it is still a WHO grade 1 benign tumor. There are several other subtypes of schwannomas in addition to the conventional type, and five subtypes have been specifically described in the 5th edition. "Melanocytic Schwannoma" in the 4th edition is now called "malignant melanotic nerve sheath tumor" in the 5th edition and is classified as a different tumor from schwannoma. Although the 5th edition places greater emphasis on genetic diagnoses, it is not essential for diagnosing schwannomas, and histological and clinical diagnoses remain equally crucial. Furthermore, after publication of the 5th edition in September 2022, an international consensus group renamed "neurofibromatosis type 2" as "NF2-related schwannomatosis." This article describes the shifts between the 4th to the 5th edition of the WHO Classification of Tumors of the Central Nervous System, along with additional clarifications, and offers the latest insights into treatment modalities for schwannomas and NF2.
Subject(s)
Central Nervous System Neoplasms , Neurilemmoma , Neurofibromatosis 2 , Humans , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurilemmoma/diagnosis , World Health OrganizationABSTRACT
BACKGROUND: Neurofibromatosis type 2 (NF2) is a multifaceted disease characterized primarily by benign CNS tumors, especially meningiomas and vestibular schwannomas. There have been several cases of brainstem ischemic stroke in young NF2 patients reported in the literature. To date, there is no unified theory about the connection between NF2 and pediatric stroke. METHODS: We present a case of ischemia in the left cerebellar peduncle of a young patient with NF2, as well as a narrative review of the literature of previous cases. RESULTS: Serial magnetic resonance images (MRIs) displayed an initial area of restricted diffusion in the left cerebellar peduncle with peripheral enhancement which did improve over several months, consistent with maturing infarct. CONCLUSIONS: Our case joins several others with similar presentations and findings. The primary theory for the cause of brainstem ischemia in juvenile NF2 is a microvascular cause due to deficiency of neurofibromin 2, a regulator of endothelial development. Multicenter studies with large NF2 cohorts are needed to better characterize this syndrome.
Subject(s)
Ischemic Stroke , Meningeal Neoplasms , Neurofibromatosis 2 , Stroke , Humans , Child , Neurofibromatosis 2/complications , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/pathology , Stroke/diagnostic imaging , Stroke/etiology , IschemiaABSTRACT
Neurofibromatosis type 2 (NF2), a multiple neoplasia syndrome, is a manifestation of an impaired expression of the merlin protein, exerting inhibitory effects on cell proliferation signals due to abnormalities of the NF2 gene located on chromosome 22. About half of patients inherit a germline mutation from a parent, and nearly 60% of de novo NF2 patients are estimated to have somatic mosaicism. The development of technical methods to detect NF2 gene mutation, including targeted deep sequencing from multiple tissues, improved the diagnostic rate of mosaic NF2. With improved understanding of genetics and pathogenesis, the diagnostic criteria for NF2 were updated to assist in identifying and diagnosing NF2 at an earlier stage. The understanding of cell signaling pathways interacting with merlin has led to the development of molecular-targeted therapies. Currently, several translational studies are searching for possible therapeutic agents targeting VEGF or VEGF receptors. Bevacizumab, an anti-VEGF monoclonal antibody, is widely used in many clinical trials aiming for hearing improvement or tumor volume control. Currently, a randomized, double-masked trial to assess bevacizumab is underway. In this randomized control trial, 12 other Japanese institutions joined the principal investigators in the clinical trial originating at Fukushima Medical University. In this review, we will be discussing the latest research developments regarding NF2 pathophysiology, including molecular biology, diagnosis, and novel therapeutics.
Subject(s)
Neurofibromatosis 2 , Humans , Neurofibromatosis 2/genetics , Neurofibromatosis 2/therapy , Neurofibromatosis 2/diagnosis , Neurofibromin 2/genetics , Neurofibromin 2/therapeutic use , Bevacizumab/genetics , Bevacizumab/therapeutic use , Mutation , Genomics , Randomized Controlled Trials as TopicABSTRACT
Neurofibromatosis (NF) and schwannomatosis (SWN) are genetic conditions characterized by the risk of developing nervous system tumors. Recently revised diagnostic criteria include the addition of genetic testing to confirm a pathogenic variant, as well as to detect the presence of mosaicism. Therefore, the use and interpretation of both germline and tumor-based testing have increasing importance in the diagnostic approach, treatment decisions, and risk stratification of these conditions. This focused review discusses approaches to genetic testing of NF- and SWN-related tumor types, which are somewhat rare and perhaps lesser known to non-specialized clinicians. These include gastrointestinal stromal tumors, breast cancer, plexiform neurofibromas with or without transformation to malignant peripheral nerve sheath tumors, gliomas, and schwannomas, and emphasizes the need for inclusion of genetic providers in patient care and appropriate pre- and post-test education, genetic counseling, and focused evaluation by a medical geneticist or other healthcare provider familiar with clinical manifestations of these disorders.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 1 , Neurofibromatosis 2 , Humans , Neurofibromatoses/diagnosis , Neurofibromatoses/genetics , Neurofibromatoses/pathology , Neurilemmoma/diagnosis , Neurilemmoma/genetics , Genetic Testing , Counseling , Neurofibromatosis 1/diagnosis , Neurofibromatosis 1/genetics , Neurofibromatosis 1/pathology , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatosis 2/therapyABSTRACT
Bilateral vestibular schwannomas are commonly diagnosed in patients affected by neurofibromatosis type 2, a genetic disease caused by a heterozygous mutation in the gene region encoding neurofibromin-2. Sporadic bilateral vestibular schwannomas are very rare entities affecting almost exclusively elderly people. We present the case of a senior woman who was followed up with the "wait-and-scan" strategy for a unilateral vestibular schwannoma that later developed as a contralateral tumor, compatible with vestibular schwannoma, raising questions about its nature and risk of having been transmitted in offspring. Genetic testing excluded mutations of the neurofibromatosis type 2 gene. The presence of bilateral vestibular schwannomas is often considered pathognomonic of neurofibromatosis type 2, but the estimated probability of sporadic bilateral tumors in the absence of other neurofibromatosis type 2 features is 50% over 70 years of age. Therefore, the NF2 gene assessment is in any case recommended in these patients not only for an evaluation of the risk of being transmitted. The treatment strategy should be carefully personalized for each patient, considering the size of the tumors, symptoms, and hearing function together with the patient's age.
Subject(s)
Neurofibromatosis 2 , Neuroma, Acoustic , Aged , Female , Humans , Hearing , Hearing Tests , Mutation , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neuroma, Acoustic/diagnosis , Neuroma, Acoustic/geneticsABSTRACT
(1) Background: This study aimed to evaluate the efficacy and treatment-related toxicity of proton radiotherapy (PRT) for vestibular schwannoma (VS) in patients with neurofibromatosis type 2-related schwannomatosis (NF2). (2) Methods: Consecutive NF2 patients treated with PRT for VS between 2004 and 2016 were retrospectively evaluated, focusing on tumor volume, facial and trigeminal nerve function, hearing, tinnitus, vestibular symptoms, and the need for salvage therapy after PRT. (3) Results: Eight patients were included (median age 36 years, 50% female). Median follow-up was 71 months. Five (63%) patients received fractionated PRT and three (38%) received PRT radiosurgery for VS. Six patients (75%) received prior VS surgery; three also received bevacizumab. Six patients (75%) did not require salvage therapy after PRT. Two patients (25%) with residual hearing lost it after PRT, and six had already lost ipsilateral hearing prior to PRT. Tumor and treatment-related morbidity could be evaluated in six patients. Following PRT, conditions that occurred or worsened were: facial paresis in five (83%), trigeminal hypoesthesia in two (33%), tinnitus in two (33%), and vestibular symptoms in four patients (67%). (4) Conclusion: After PRT for VS, the majority of the NF2 patients in the cohort did not require additional therapy. Tumor and/or treatment-related cranial nerve deficits were common. This is at least partly explained by the use of PRT as a salvage treatment after surgery or bevacizumab, in the majority of cases. There remains the further opportunity to elucidate the efficacy and toxicity of proton radiotherapy as a primary treatment.
Subject(s)
Neurofibromatosis 2 , Neuroma, Acoustic , Tinnitus , Humans , Female , Adult , Male , Neurofibromatosis 2/complications , Neurofibromatosis 2/radiotherapy , Neurofibromatosis 2/diagnosis , Neuroma, Acoustic/radiotherapy , Neuroma, Acoustic/surgery , Protons , Retrospective Studies , Bevacizumab/therapeutic use , Treatment Outcome , Follow-Up StudiesABSTRACT
Genetic testing and management of individuals at risk for NF2-related schwannomatosis is complicated by the high rate of mosaicism resulting in a milder, later onset, more asymmetrical disease and the phenotypic overlap with the related schwannomatosis conditions. This updated protocol has been devised for the English NF2-related schwannomatosis service. It provides those affected with mosaic NF2-related schwannomatosis estimated risks of having an affected child; and management guidelines both for individuals at risk of NF2-related schwannomatosis, or with potential disease, due to having features that fall short of consensus diagnostic criteria. Risks of mosaicism and inferred transmission risks were derived from genetic testing of over 1000 individuals through the Manchester NF2 genetic testing service. This updated protocol, reflects the lower transmission risks now inferred in mosaic NF2-related schwannomatosis, informed by the greater sensitivity of Next Generation Sequencing in detecting low levels of mosaicism in blood, along with improved ability to analyse tumour DNA. Screening for features of NF2-related schwannomatosis is proposed until the risk of having the condition falls below a pragmatic threshold of 1%. Using these revised transmission figures, this threshold can now be reached at a younger age in many of those at risk, with earlier reassurance and discharge.
Subject(s)
Neurilemmoma , Neurofibromatoses , Neurofibromatosis 2 , Skin Neoplasms , Child , Humans , Neurofibromatoses/diagnosis , Neurofibromatoses/genetics , Neurofibromatoses/pathology , Neurilemmoma/diagnosis , Neurilemmoma/genetics , Neurilemmoma/pathology , Skin Neoplasms/diagnosis , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Genetic Testing , Neurofibromatosis 2/diagnosis , Neurofibromatosis 2/genetics , Neurofibromatosis 2/therapyABSTRACT
A 77-year old female with a history of neurofibromatosis type 2 (NF2) was diagnosed with a spinal schwannoma that was managed conservatively over a decade. During this time, follow up imaging revealed this lesion had been growing and the patient had become symptomatic from it necessitating surgical decompression. However, the patient had been diagnosed with multiple myeloma and underwent treatment with Pomalidomide chemotherapy which delayed surgery for the spinal schwannoma. Further imaging of the spine revealed significant regression in the size of the spinal schwannoma. This phenomenon has not previously been reported and this report aims to explore the implications of Pomalidomide in patients with NF2 related spinal schwannomas.