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Loh J, Ong PY, Goh DLM, Puhaindran ME, Vellayappan BA, Ow SGW, Chan G, Lee SC. Clinical characteristics and genetic testing outcome of suspected hereditary peripheral nerve sheath tumours in a tertiary cancer institution in Singapore. Hered Cancer Clin Pract 2022; 20:23. [PMID: 35698239 PMCID: PMC9195433 DOI: 10.1186/s13053-022-00230-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 05/27/2022] [Indexed: 12/03/2022] Open
Abstract
Background Peripheral Nerve Sheath Tumors (PNST) are a diverse group of mostly benign tumours uncommon in the general population. About 5–10% of PNSTs are hereditary, predominantly arising from germline variants in NF1, NF2, SMARCB1, or LZTR1 gene. Methods We reviewed the clinical characteristics and genetic testing results of patients referred to the NCIS Adult Cancer Genetics Clinic for suspected hereditary PNST. Results 3,001 patients suspected to have various hereditary cancer syndromes were evaluated between year 2000 to March 2021. 13 (0.4%) were clinically diagnosed to have hereditary PNSTs. The majority were male (54%), with a median age at presentation to the genetics clinic of 29 years (range 19–48). 11/13 (85%) patients had multiple PNSTs, 12/13 (92%) had young onset PNSTs, 5/13 (38.5%) had personal and family history of PNST. 11/13 patients (85%) had clinical features of neurofibromatosis type 1 (NF1) including one patient who also fulfilled clinical criteria of neurofibromatosis type 2 (NF2); 2/13 (14%) had multiple schwannomas. Four patients underwent multi-gene panel testing, including one patient with clinical NF1, one patient who met both clinical NF1 and NF2 criteria, and two patients with multiple schwannomas. The patient with clinical features of NF1 was heterozygous for a pathogenic c. 2033dup variant in the NF1 gene. The patient with both NF1/NF2 features was heterozygous for a novel c.732 T > A nonsense variant in the NF2 gene. The two patients with multiple schwannomas were heterozygous for a pathogenic/likely pathogenic variant in the LZTR1 gene and are the first LZTR1-positive schwannomatosis patients reported in Asia. Conclusion Hereditary PNSTs are rare referrals to an adult cancer genetics clinic. NF1 is the most common PNST seen. LZTR1 variants may be the underlying cause in Asian patients with multiple schwannomatosis. Supplementary Information The online version contains supplementary material available at 10.1186/s13053-022-00230-4.
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Affiliation(s)
- Jerold Loh
- Department of Haematology-Oncology, NCIS, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Pei Yi Ong
- Department of Haematology-Oncology, NCIS, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Denise Li Meng Goh
- Division of Paediatric Genetics and Metabolism, Department of Paediatrics, Khoo Teck Puat - National University Children's Medical Institute, National University Hospital, Singapore, Singapore
| | - Mark E Puhaindran
- Department of Hand and Reconstructive Microsurgery, National University Hospital, Singapore, Singapore
| | | | - Samuel Guan Wei Ow
- Department of Haematology-Oncology, NCIS, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Gloria Chan
- Department of Haematology-Oncology, NCIS, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Soo-Chin Lee
- Department of Haematology-Oncology, NCIS, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore. .,Cancer Science Institute, Singapore, Singapore.
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Tolliver S, Smith ZI, Silverberg N. The Genetics and Diagnosis of Pediatric Neurocutaneous Disorders: Neurofibromatosis and Tuberous Sclerosis Complex. Clin Dermatol 2022. [PMID: 35248688 DOI: 10.1016/j.clindermatol.2022.02.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neurofibromatosis (NF) and tuberous sclerosis complex (TSC) are the two most common neurocutaneous disorders, both transmitted as autosomal dominant or, in the case of NF, also as a mosaic condition. The causative genetic mutations in these neurocutaneous disorders can lead to benign skin changes or uninhibited growth and proliferation in multiple organ systems due to the loss of tumor suppression in mitogen-activated protein kinase and mammalian target of rapamycin signaling pathways. Common clinical features in NF include pigmented lesions, known as café au lait patches, neurofibromas, intertriginous freckles (Crowe's sign), and benign fibrous growths, such as hamartomas in multiple organ systems. Common clinical features in TSC include hypopigmented macules, known as ash leaf spots, in addition to neurologic sequelae, such as autism, seizures, and developmental delays. Advances in genetic sequencing technologies have allowed an exponential expansion in the understanding of NF and TSC. Consensus criteria have been established for both diagnoses that can be confirmed in most cases through gene testing. Once diagnosed, the clinical and diagnostic value of disease-specific surveillance include early identification of benign and malignant tumors. Genetic counseling is important for informed reproductive decision-making for patients and at-risk family members. The improvement in understanding of pathways of pathogenic disease development and oncogenesis in both conditions have produced a new series of therapeutic options that can be used to control seizures and tumor growth. Tremendous advances in life expectancy and quality of life are now a reality due to early introduction of seizure control and novel medications. While we lack cures, early institution of interventions, such as seizure control in tuberous sclerosis, appears to be disease-modifying and holds immense promise to offer patients better lives.
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Tamura R. Current Understanding of Neurofibromatosis Type 1, 2, and Schwannomatosis. Int J Mol Sci 2021; 22:5850. [PMID: 34072574 DOI: 10.3390/ijms22115850] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 05/25/2021] [Accepted: 05/28/2021] [Indexed: 12/16/2022] Open
Abstract
Neurofibromatosis (NF) is a neurocutaneous syndrome characterized by the development of tumors of the central or peripheral nervous system including the brain, spinal cord, organs, skin, and bones. There are three types of NF: NF1 accounting for 96% of all cases, NF2 in 3%, and schwannomatosis (SWN) in <1%. The NF1 gene is located on chromosome 17q11.2, which encodes for a tumor suppressor protein, neurofibromin, that functions as a negative regulator of Ras/MAPK and PI3K/mTOR signaling pathways. The NF2 gene is identified on chromosome 22q12, which encodes for merlin, a tumor suppressor protein related to ezrin-radixin-moesin that modulates the activity of PI3K/AKT, Raf/MEK/ERK, and mTOR signaling pathways. In contrast, molecular insights on the different forms of SWN remain unclear. Inactivating mutations in the tumor suppressor genes SMARCB1 and LZTR1 are considered responsible for a majority of cases. Recently, treatment strategies to target specific genetic or molecular events involved in their tumorigenesis are developed. This study discusses molecular pathways and related targeted therapies for NF1, NF2, and SWN and reviews recent clinical trials which involve NF patients.
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Herrero San Martín A, Alcalá-Galiano A. Schwannoma of the posterior tibial nerve in a patient with schwannomatosis and a novel mutation of the LZTR1 gene. Neurología (English Edition) 2020. [DOI: 10.1016/j.nrleng.2019.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Herrero San Martín A, Alcalá-Galiano A. Schwannoma del nervio tibial en un paciente con schwannomatosis asociada a una nueva mutación en el gen LZTR1. Neurologia 2020; 35:657-659. [DOI: 10.1016/j.nrl.2019.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Accepted: 07/18/2019] [Indexed: 10/25/2022] Open
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Ding Y, Rong H, Wang Y, Liu T, Zhang J, Li S, Wang Z, Wang Y, Zhu T. Detection of Germline Mutations of the SMARCB1 Gene in a Chinese Family with Intraspinal Schwannomatosis. World Neurosurg 2019; 123:318-22. [DOI: 10.1016/j.wneu.2018.11.254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 11/24/2022]
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Ding Y, Rong H, Liu T, Wang Y, Zhang J, Li S, Zhu T. Malignant Peripheral Nerve Sheath Tumor Arising in Schwannomatosis with Multiple Lung Metastases. World Neurosurg 2018; 119:335-339. [PMID: 30144611 DOI: 10.1016/j.wneu.2018.08.087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/12/2018] [Accepted: 08/13/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND Malignant peripheral nerve sheath tumor (MPNST) is a kind of rare neurogenic malignancy, which usually arises from nerve fibers in any tissue and organ that have nerve fiber distributions, especially the trunk and extremities, but it is extremely rare in spinal canal. CASE DESCRIPTION We report a 30-year-old woman who had a history of excision of intraspinal occupying lesions 5 times and the pathologic diagnosis based on histomorphologic and immunohistochemistry was schwannomatosis, which existed in her family history. Unfortunately, she died because her condition deteriorated rapidly and appeared multiple lung metastases. MPNST was confirmed by needle biopsy of lung lesions. CONCLUSIONS Many cases of MPNST usually developed from neurofibromatosis type 1. However, the incidence of MPNST arising from schwannomatosis was extremely rare. More significantly, using genetic testing on her, we found a splice site mutation (c.1118+1G>A) that occurred between exons 8 and 9 of the SMARCB1 gene, which was first found in this MPNST patient and could lay the foundation for further study of its pathogenesis.
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Affiliation(s)
- Yuhui Ding
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Hongtao Rong
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Tong Liu
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Yi Wang
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Jinhao Zhang
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Sipeng Li
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China
| | - Tao Zhu
- Department of Neurosurgery Tianjin Medical University General Hospital, Heping District, Tianjin, China.
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Abstract
While the clinicopathologic features of pediatric vestibular schwannomas, often in the context of neurofibromatosis type 2 (NF2), have been well studied, there is less data regarding the characteristics of pediatric non-vestibular schwannomas (NVS). Additionally, the rate of loss of SMARCB1/INI1 expression in this population has not been systematically evaluated. Our institutional archives were searched for cases of NVS arising in patients 18 years or younger. Clinicopathologic features including SMARCB1/INI1 status were assessed for each case. Twenty-three NVS from 9 males and 13 females (age range, 2 months to 18 years) were identified, and sites included paraspinal (n = 10), head and neck (n = 6), extremities (n = 4), trunk (n = 1), mediastinum (n = 1), and retroperitoneum (n = 1); 22 cases were Antoni A predominant with 6 cases comprising solely Antoni A tissue. The mitotic rate of the tumors ranged from 0 to 10/10 high-power fields (HPFs), and 3 tumors had mitotic rates of ≥4 mitoses/10 HPFs. Two tumors showed plexiform architecture. No NVS showed diffuse atypia, calcifications, microcystic/reticular architecture, epithelioid morphology, pseudoglandular change, neuroblastoma-like features, or necrosis. All tumors tested (23/23) showed retained nuclear expression of SMARCB1/INI1. Follow-up was available in 21 patients (range 1 week to 194 months), and 5 tumors recurred. Pediatric NVS have a relatively homogeneous appearance with a predominance of Antoni A areas. Pathologists should be aware that schwannomas in this age group may be cellular with mitotic rates of ≥4/10 HPFs to avoid misclassification as a spindle cell sarcoma.
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Affiliation(s)
- Cory Broehm
- 1 Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Alyaa Al-Ibraheemi
- 1 Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Karen J Fritchie
- 1 Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
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Kehrer-Sawatzki H, Farschtschi S, Mautner VF, Cooper DN. The molecular pathogenesis of schwannomatosis, a paradigm for the co-involvement of multiple tumour suppressor genes in tumorigenesis. Hum Genet 2016; 136:129-148. [PMID: 27921248 PMCID: PMC5258795 DOI: 10.1007/s00439-016-1753-8] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/27/2016] [Indexed: 12/20/2022]
Abstract
Schwannomatosis is characterized by the predisposition to develop multiple schwannomas and, less commonly, meningiomas. Despite the clinical overlap with neurofibromatosis type 2 (NF2), schwannomatosis is not caused by germline NF2 gene mutations. Instead, germline mutations of either the SMARCB1 or LZTR1 tumour suppressor genes have been identified in 86% of familial and 40% of sporadic schwannomatosis patients. In contrast to patients with rhabdoid tumours, which are due to complete loss-of-function SMARCB1 mutations, individuals with schwannomatosis harbour predominantly hypomorphic SMARCB1 mutations which give rise to the synthesis of mutant proteins with residual function that do not cause rhabdoid tumours. Although biallelic mutations of SMARCB1 or LZTR1 have been detected in the tumours of patients with schwannomatosis, the classical two-hit model of tumorigenesis is insufficient to account for schwannoma growth, since NF2 is also frequently inactivated in these tumours. Consequently, tumorigenesis in schwannomatosis must involve the mutation of at least two different tumour suppressor genes, an occurrence frequently mediated by loss of heterozygosity of large parts of chromosome 22q harbouring not only SMARCB1 and LZTR1 but also NF2. Thus, schwannomatosis is paradigmatic for a tumour predisposition syndrome caused by the concomitant mutational inactivation of two or more tumour suppressor genes. This review provides an overview of current models of tumorigenesis and mutational patterns underlying schwannomatosis that will ultimately help to explain the complex clinical presentation of this rare disease.
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Affiliation(s)
| | - Said Farschtschi
- Department of Neurology, University Hospital Hamburg Eppendorf, 20246, Hamburg, Germany
| | - Victor-Felix Mautner
- Department of Neurology, University Hospital Hamburg Eppendorf, 20246, Hamburg, Germany
| | - David N Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
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Abstract
The etiology of most childhood cancer remains largely unknown, but is likely attributable to random or induced genetic aberrations in somatic tissue. However, a subset of children develops cancer in the setting of an underlying inheritable condition involving a germline genetic mutation or chromosomal aberration. The term "neurocutaneous syndrome" encompasses a group of multisystem, hereditary disorders that are associated with skin manifestations as well as central and/or peripheral nervous system lesions of variable severity. This review outlines the central nervous system tumors associated with underlying neurocutaneous disorders, including neurofibromatosis type 1, neurofibromatosis type 2, schwannomatosis, tuberous sclerosis complex, Von Hippel Lindau, and nevoid basal cell carcinoma syndrome. Recognizing the presence of an underlying syndrome is critically important to both optimizing clinical care and treatment as well as genetic counseling and monitoring of these affected patients and their families.
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Affiliation(s)
- Nicole J Ullrich
- Department of Neurology, Boston Children's Hospital and Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Harvard Medical School, Boston, MA, USA
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11
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Farschtschi S, Mautner VF, Pham M, Nguyen R, Kehrer-Sawatzki H, Hutter S, Friedrich RE, Schulz A, Morrison H, Jones DTW, Bendszus M, Bäumer P. Multifocal nerve lesions andLZTR1germline mutations in segmental schwannomatosis. Ann Neurol 2016; 80:625-8. [DOI: 10.1002/ana.24753] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 07/26/2016] [Accepted: 07/27/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Said Farschtschi
- Department of Neurology; University Medical Center Hamburg-Eppendorf, University of Hamburg; Hamburg Germany
| | - Victor-Felix Mautner
- Department of Neurology; University Medical Center Hamburg-Eppendorf, University of Hamburg; Hamburg Germany
| | - Mirko Pham
- Department of Neuroradiology; Heidelberg University Hospital; Heidelberg Germany
| | - Rosa Nguyen
- Department of Oncology; St Jude Children's Research Hospital; Memphis TN
| | | | - Sonja Hutter
- Division of Pediatric Neuro-oncology; German Cancer Research Center; Heidelberg Germany
| | - Reinhard E. Friedrich
- Department of Maxillofacial Surgery; University Medical Center Hamburg-Eppendorf, University of Hamburg; Hamburg Germany
| | - Alexander Schulz
- Leibniz Institute on Aging; Fritz Lipmann Institute; Jena Germany
| | - Helen Morrison
- Leibniz Institute on Aging; Fritz Lipmann Institute; Jena Germany
| | - David T. W. Jones
- Division of Pediatric Neuro-oncology; German Cancer Research Center; Heidelberg Germany
| | - Martin Bendszus
- Department of Neuroradiology; Heidelberg University Hospital; Heidelberg Germany
| | - Philipp Bäumer
- Department of Neuroradiology; Heidelberg University Hospital; Heidelberg Germany
- Department of Radiology; German Cancer Research Center; Heidelberg Germany
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Lieber B, Han B, Allen J, Fatterpekar G, Agarwal N, Kazemi N, Zagzag D. Utility of positron emission tomography in schwannomatosis. J Clin Neurosci 2016; 30:138-140. [PMID: 26960263 DOI: 10.1016/j.jocn.2016.01.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 01/26/2016] [Indexed: 10/22/2022]
Abstract
Schwannomatosis is characterized by multiple non-intradermal schwannomas with patients often presenting with a painful mass in their extremities. In this syndrome malignant transformation of schwannomas is rare in spite of their large size at presentation. Non-invasive measures of assessing the biological behavior of plexiform neurofibromas in neurofibromatosis type 1 such as positron emission tomography (PET), CT scanning and MRI are well characterized but little information has been published on the use of PET imaging in schwannomatosis. We report a unique clinical presentation portraying the use of PET imaging in schwannomatosis. A 27-year-old woman presented with multiple, rapidly growing, large and painful schwannomas confirmed to be related to a constitutional mutation in the SMARCB1 complex. Whole body PET/MRI revealed numerous PET-avid tumors suggestive of malignant peripheral nerve sheath tumors. Surgery was performed on multiple tumors and none of them had histologic evidence of malignant transformation. Overall, PET imaging may not be a reliable predictor of malignant transformation in schwannomatosis, tempering enthusiasm for surgical interventions for tumors not producing significant clinical signs or symptoms.
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Affiliation(s)
- Bryan Lieber
- Department of Neurological Surgery, University of Arkansas for Medical Sciences, 4301 W. Markham Street, #507, Little Rock, AR 72205, USA.
| | - ByoungJun Han
- New York University School of Medicine, New York, NY, USA
| | - Jeffrey Allen
- Department of Pediatric Neuro-oncology, New York University School of Medicine, New York, NY, USA
| | - Girish Fatterpekar
- Department of Neuroradiology, New York University School of Medicine, New York, NY, USA
| | - Nitin Agarwal
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Noojan Kazemi
- Department of Neurological Surgery, University of Arkansas for Medical Sciences, 4301 W. Markham Street, #507, Little Rock, AR 72205, USA
| | - David Zagzag
- Department of Neuropathology, New York University School of Medicine, New York, NY, USA
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Abstract
Bladder masses are represented by either benign or malignant entities. Malignant bladder tumors are frequent causes of disease and death in western countries. However, in children they are less common. Additionally, different features are found in childhood, in which non epithelial tumors are more common than epithelial ones. Rhabdomyosarcoma is the most common pediatric bladder tumor, but many other types of lesions may be found, such as malignant rhabdoid tumor (MRT), inflammatory myofibroblastic tumor and neuroblastoma. Other rarer tumors described in literature include urothelial carcinoma and other epithelial neoplasms. Rhabdomyosarcoma is associated to a variety of genetic syndromes and many genes are involved in tumor development. PAX3-FKHR and PAX7-FKHR (P-F) fusion state has important implications in the pathogenesis and biology of RMS, and different genes alterations are involved in the pathogenesis of P-F negative and embryonal RMS, which are the subsets of tumors most frequently affecting the bladder. These genes include p53, MEF2, MYOG, Ptch1, Gli1, Gli3, Myf5, MyoD1, NF1, NRAS, KRAS, HRAS, FGFR4, PIK3CA, CTNNB1, FBXW7, IGF1R, PDGFRA, ERBB2/4, MET, BCOR. Malignant rhabdoid tumor (MRT) usually shows SMARCB1/INI1 alterations. Anaplastic lymphoma kinase (ALK) gene translocations are the most frequently associated alterations in inflammatory myofibroblastic tumor (IMT). Few genes alterations in urothelial neoplasms have been reported in the paediatric population, which are mainly related to deletion of p16/lnk4, overexpression of CK20 and overexpression of p53. Here, we reviewed available literature to identify genes associated to bladder malignancies in children and discussed their possible relationships with these tumors.
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Affiliation(s)
| | - Johan Zaini
- Università degli Studi della Tuscia, dipartimento di scienze biologiche (DEB), Viterbo, Italy
| | - Caterina Gulìa
- Università degli Studi di Roma La Sapienza, Dipartimento di Urologia, Roma, Italy
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Spyra M, Otto B, Schön G, Kehrer-Sawatzki H, Mautner VF. Determination of the mutant allele frequency in patients with neurofibromatosis type 2 and somatic mosaicism by means of deep sequencing. Genes Chromosomes Cancer 2015; 54:482-488. [PMID: 26031996 DOI: 10.1002/gcc.22259] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/20/2015] [Accepted: 03/21/2015] [Indexed: 12/17/2022] Open
Abstract
Neurofibromatosis Type 2 (NF2) is an autosomal disorder caused by mutations of the NF2 gene. More than half of all NF2 patients have unaffected parents and carry de novo mutations, which may be of prezygotic or postzygotic origin. The latter can result in mosaicism, which is relatively common in NF2 patients. Previous studies indicated that, in 50% of patients with mosaic NF2 mutations, the mutant allele is only detectable by Sanger sequencing of PCR products amplified from tumor tissue but not from blood samples. In order to establish a highly sensitive method that has the power to detect low levels of NF2 mutant alleles from blood samples of mosaic NF2 patients, we performed ultra deep sequencing and calculated the percentage of mutant and wildtype NF2 alleles. The mutant allele frequencies detected ranged from 2.6% to 19.7%. In three patients, however, the NF2 mutation previously identified in tumor tissue was not identified in blood samples by means of deep sequencing, suggesting absence of mutant cells in the blood. Remarkably, we observed a correlation between the age at onset of the disease and the mutant allele frequency. Our study indicates that ultra deep sequencing is an effective and highly sensitive method to determine the mutant allele frequency in patients with mosaic NF2 gene mutations, which enables extended phenotype/correlations in these patients. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Melanie Spyra
- Department of Neurology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Benjamin Otto
- Department of Internal Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Gerhard Schön
- Department of Medical Biometry and Epidemiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | | | - Victor-Felix Mautner
- Department of Neurology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
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15
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Stockman DL, Curry JL, Torres-Cabala CA, Watson IR, Siroy AE, Bassett RL, Zou L, Patel KP, Luthra R, Davies MA, Wargo JA, Routbort MA, Broaddus RR, Prieto VG, Lazar AJ, Tetzlaff MT. Use of clinical next-generation sequencing to identify melanomas harboringSMARCB1mutations. J Cutan Pathol 2015; 42:308-17. [DOI: 10.1111/cup.12481] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 02/01/2015] [Indexed: 12/26/2022]
Affiliation(s)
- David L. Stockman
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Jonathan L. Curry
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Carlos A. Torres-Cabala
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Ian R. Watson
- Department of Genomic Medicine; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Alan E. Siroy
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Roland L. Bassett
- Department of Biostatistics; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Lihua Zou
- The Eli and Edythe L. Broad Institute of Massachusetts; Institute of Technology and Harvard University; Cambridge Massachusetts USA
| | - Keyur P. Patel
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Rajyalakshmi Luthra
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Michael A. Davies
- Department of Melanoma Medical Oncology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Jennifer A. Wargo
- Department of Surgery; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Mark A. Routbort
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Russell R. Broaddus
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Victor G. Prieto
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Alexander J. Lazar
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
| | - Michael T. Tetzlaff
- Department of Pathology and Laboratory Medicine, Section of Dermatopathology; The University of Texas MD Anderson Cancer Center; Houston TX USA
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Abstract
Rhabdoid tumors (RT), or malignant rhabdoid tumors, are among the most aggressive and lethal forms of human cancer. They can arise in any location in the body but are most commonly observed in the brain, where they are called atypical teratoid/rhabdoid tumors (AT/RT), and in the kidneys, where they are called rhabdoid tumors of the kidney. The vast majority of rhabdoid tumors present with a loss of function in the SMARCB1 gene, also known as INI1, BAF47, and hSNF5, a core member of the SWI/SNF chromatin-remodeling complex. Recently, mutations in a 2nd locus of the SWI/SNF complex, the SMARCA4 gene, also known as BRG1, were found in rhabdoid tumors with retention of SMARCB1 expression. Familial cases may occur in a condition known as rhabdoid tumor predisposition syndrome (RTPS). In RTPS, germline inactivation of 1 allele of a gene occurs. When the mutation occurs in the SMARCB1 gene, the syndrome is called RTPS1, and when the mutation occurs in the SMARCA4 gene it is called RTPS2. Children presenting with RTPS tend to develop tumors at a younger age, but the impact that germline mutation has on survival remains unclear. Adults who carry the mutation tend to develop multiple schwannomas. The diagnosis of RTPS should be considered in patients with RT, especially if they have multiple primary tumors, and/or in individuals with a family history of RT. Because germline mutations result in an increased risk of carriers developing RT, genetic counseling for families with this condition is recommended.
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Affiliation(s)
- Simone T Sredni
- 1 Ann and Robert H. Lurie Children's Hospital of Chicago-Division of Pediatric Neurosurgery, 225 E. Chicago Avenue Box #28, Chicago, IL 60611, USA
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Abstract
Schwannomas may occur spontaneously, or in the context of a familial tumor syndrome such as neurofibromatosis type 2 (NF2), schwannomatosis and Carney's complex. Schwannomas have a variety of morphological appearances, but they behave as World Health Organization (WHO) grade I tumors, and only very rarely undergo malignant transformation. Central to the pathogenesis of these tumors is loss of function of merlin, either by direct genetic change involving the NF2 gene on chromosome 22 or secondarily to merlin inactivation. The genetic pathways and morphological features of schwannomas associated with different genetic syndromes will be discussed. Merlin has multiple functions, including within the nucleus and at the cell membrane, and this review summarizes our current understanding of the mechanisms by which merlin loss is involved in schwannoma pathogenesis, highlighting potential areas for therapeutic intervention.
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Affiliation(s)
- David A Hilton
- Department of Cellular and Anatomical Pathology, Derriford Hospital, Plymouth, UK
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Folpe AL. Selected topics in the pathology of epithelioid soft tissue tumors. Mod Pathol 2014; 27 Suppl 1:S64-79. [PMID: 24384854 DOI: 10.1038/modpathol.2013.175] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 07/17/2013] [Accepted: 07/19/2013] [Indexed: 01/22/2023]
Abstract
Epithelioid morphology, mimicking carcinoma, is a key or defining feature of several soft tissue tumors and may be seen in a wide variety of other tumors. This review will focus on those tumors defined at least in part by their epithelioid morphology, in particular epithelioid sarcoma, epithelioid malignant peripheral nerve sheath tumor, and sclerosing epithelioid fibrosarcoma. The role of loss of the SMARCB1 tumor-suppressor gene in the pathogenesis of these epithelioid soft tissue tumors will be discussed, as will their differential diagnosis with non-mesenchymal tumors, in particular carcinoma and melanoma.
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Koontz NA, Wiens AL, Agarwal A, Hingtgen CM, Emerson RE, Mosier KM. Schwannomatosis: The Overlooked Neurofibromatosis? AJR Am J Roentgenol 2013; 200:W646-53. [DOI: 10.2214/ajr.12.8577] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Plotkin SR, Blakeley JO, Evans DG, Hanemann CO, Hulsebos TJM, Hunter-Schaedle K, Kalpana GV, Korf B, Messiaen L, Papi L, Ratner N, Sherman LS, Smith MJ, Stemmer-Rachamimov AO, Vitte J, Giovannini M. Update from the 2011 International Schwannomatosis Workshop: From genetics to diagnostic criteria. Am J Med Genet A 2013; 161A:405-16. [PMID: 23401320 DOI: 10.1002/ajmg.a.35760] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 10/13/2012] [Indexed: 11/06/2022]
Abstract
Schwannomatosis is the third major form of neurofibromatosis and is characterized by the development of multiple schwannomas in the absence of bilateral vestibular schwannomas. The 2011 Schwannomatosis Update was organized by the Children's Tumor Foundation (www.ctf.org) and held in Los Angeles, CA, from June 5-8, 2011. This article summarizes the highlights presented at the Conference and represents the "state-of-the-field" in 2011. Genetic studies indicate that constitutional mutations in the SMARCB1 tumor suppressor gene occur in 40-50% of familial cases and in 8-10% of sporadic cases of schwannomatosis. Tumorigenesis is thought to occur through a four-hit, three-step model, beginning with a germline mutation in SMARCB1 (hit 1), followed by loss of a portion of chromosome 22 that contains the second SMARCB1 allele and one NF2 allele (hits 2 and 3), followed by mutation of the remaining wild-type NF2 allele (hit 4). Insights from research on HIV and pediatric rhabdoid tumors have shed light on potential molecular pathways that are dysregulated in schwannomatosis-related schwannomas. Mouse models of schwannomatosis have been developed and promise to further expand our understanding of tumorigenesis and the tumor microenvironment. Clinical reports have described the occurrence of intracranial meningiomas in schwannomatosis patients and in families with germline SMARCB1 mutations. The authors propose updated diagnostic criteria to incorporate new clinical and genetic findings since 2005. In the next 5 years, the authors expect that advances in basic research in the pathogenesis of schwannomatosis will lead toward clinical investigations of potential drug therapies.
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Affiliation(s)
- Scott R Plotkin
- Department of Neurology and Cancer Center, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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Rizzo D, Fréneaux P, Brisse H, Louvrier C, Lequin D, Nicolas A, Ranchère D, Verkarre V, Jouvet A, Dufour C, Edan C, Stéphan JL, Orbach D, Sarnacki S, Pierron G, Parfait B, Peuchmaur M, Delattre O, Bourdeaut F. SMARCB1 deficiency in tumors from the peripheral nervous system: a link between schwannomas and rhabdoid tumors? Am J Surg Pathol 2012; 36:964-72. [PMID: 22614000 DOI: 10.1097/PAS.0b013e31825798f1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Inactivation of SMARCB1 tumor-suppressor gene was originally described as highly specific for rhabdoid tumors (RTs). Nevertheless, recent reports have illustrated that SMARCB1 alterations also characterize other tumors; in particular, some familial schwannomatosis and epithelioid malignant peripheral nerve sheath tumors, both from peripheral nervous system (PNS) origin, lack BAF47 expression. To document the putative role of SMARCB1 in PNS, we reviewed PNS tumors referred to our institution for a molecular analysis of SMARCB1 because of histologic features compatible with RT. METHODS Clinicopathologic, radiologic, and molecular characteristics were detailed for the 12 cases showing loss of expression and/or biallelic inactivation of SMARCB1. The status of the NF2 gene, likely to synergize with SMARCB1 in PNS tumors, was also analyzed. RESULTS Patients' age ranged from 0 to 45 years (median age, 6.6 y). Neurological symptoms were observed in 7/12 cases with radiologic features evoking a neuroblastic tumor in 6 cases and a peripheral nerve tumor in 4 cases. The mean delay before diagnosis was 3 months. Histologic examination revealed rhabdoid features in 11/12 tumors. All tumors showed a complete loss of SMARCB1 expression. Interestingly, adjacent nervous proliferation resembling neurofibromas were observed in 3 cases, suggesting a multistep transformation. Three tumors harbored a hemizygous deletion at the NF2 locus, but all NF2 sequences were normal. CONCLUSIONS We report the first series of PNS RT. In patients with aggressive PNS tumors, RT should be suspected, and anti-SMARCB1 immunohistochemical analysis should be performed. SMARCB1 inactivation, occasionally associated with NF2 deletion, might have oncogenic effects in peripheral nerves.
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Carter JM, O'Hara C, Dundas G, Gilchrist D, Collins MS, Eaton K, Judkins AR, Biegel JA, Folpe AL. Epithelioid malignant peripheral nerve sheath tumor arising in a schwannoma, in a patient with "neuroblastoma-like" schwannomatosis and a novel germline SMARCB1 mutation. Am J Surg Pathol. 2012;36:154-160. [PMID: 22082606 DOI: 10.1097/pas.0b013e3182380802] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Epithelioid malignant peripheral nerve sheath tumors arising in preexisting schwannomas are extremely rare. We report an unusual example occurring in a patient with multiple schwannomas (schwannomatosis), all but 1 of which showed "neuroblastoma-like" histology. By immunohistochemistry, both the epithelioid malignant peripheral nerve sheath tumor and the schwannomas showed a complete loss of the Smarcb1 protein. Subsequent genetic evaluation revealed the presence of a novel germline mutation in the SMARCB1/INI1 gene in the patient and in 3 of her children, 2 of whom were diagnosed with atypical teratoid/rhabdoid tumors of the brain.
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Abstract
Significant progress has been made in understanding the molecular genetic alterations involved in sarcomagenesis. Cytogenetic and molecular studies have identified nonrandom genetic abnormalities, including tumor suppressor gene inactivation. Mutations, deletions, and other somatic alterations in the tumor suppressor gene INI1 (hSNF5; SMARCB1), which encodes a subunit of the SWI/SNF chromatin remodeling complex, were first described in the malignant rhabdoid tumor of infancy. Since then, INI1 has also been implicated in the pathogenesis of additional tumor types including renal medullary carcinomas and epithelioid sarcomas and a subset of epithelioid malignant peripheral nerve sheath tumors, myoepithelial carcinomas, and extraskeletal myxoid chondrosarcomas. As varied as this group appears, they all show loss of INI1 protein expression, a propensity for rhabdoid cytomorphology, and sometimes other overlapping immunohistochemical and histologic findings. We will review the clinicopathologic features of these tumor types and emphasize the clinical utility of INI1 immunohistochemistry in differential diagnosis.
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Bartolomé-García S, de la Cuadra-Virgili P, Jiménez-Cristóbal J. Schwannomatosis múltiple bilateral: a propósito de un caso. Rev Esp Cir Ortop Traumatol (Engl Ed) 2011. [DOI: 10.1016/j.recot.2011.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Rousseau G, Noguchi T, Bourdon V, Sobol H, Olschwang S. SMARCB1/INI1 germline mutations contribute to 10% of sporadic schwannomatosis. BMC Neurol 2011; 11:9. [PMID: 21255467 PMCID: PMC3037869 DOI: 10.1186/1471-2377-11-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 01/24/2011] [Indexed: 11/23/2022] Open
Abstract
Background Schwannomatosis is a disease characterized by multiple non-vestibular schwannomas. Although biallelic NF2 mutations are found in schwannomas, no germ line event is detected in schwannomatosis patients. In contrast, germline mutations of the SMARCB1 (INI1) tumor suppressor gene were described in familial and sporadic schwannomatosis patients. Methods To delineate the SMARCB1 gene contribution, the nine coding exons were sequenced in a series of 56 patients affected with a variable number of non-vestibular schwannomas. Results Nine variants scattered along the sequence of SMARCB1 were identified. Five of them were classified as deleterious. All five patients carrying a SMARCB1 mutation had more multiple schwannomas, corresponding to 10.2% of patients with schwannomatosis. They were also diagnosed before 35 years of age. Conclusions These results suggest that patients with schwannomas have a significant probability of carrying a SMARCB1 mutation. Combined with data available from other studies, they confirm the clinical indications for genetic screening of the SMARCB1 gene.
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Affiliation(s)
- Guillaume Rousseau
- Laboratory of Molecular Oncogenetics, Institut Paoli-Calmettes, Marseille, France
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Bartolomé-garcía S, de la Cuadra-virgili P, Jiménez-cristóbal J. Multiple bilateral schwannomatosis: presentation of a case. Rev Esp Cir Ortop Traumatol (Engl Ed) 2011; 55:220-223. [DOI: 10.1016/s1988-8856(11)70309-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Abstract
BACKGROUND Germline mutations and deletions of SMARCB1/INI1 in chromosome band 22q11.2 predispose patients to rhabdoid tumor and schwannomatosis. Previous estimates suggested that 15-20% of rhabdoid tumors were caused by an underlying germline abnormality of SMARCB1. However, these studies were limited by case selection and an inability to detect intragenic deletions and duplications. PROCEDURE One hundred matched tumor and blood samples from patients with rhabdoid tumors of the brain, kidney, or soft tissues were analyzed for mutations and deletions of SMARCB1 by FISH, multiplex ligation-dependent probe amplification (MLPA), sequence analysis and high resolution Illumina 610K SNP-based oligonucleotide array studies. RESULTS Thirty-five of 100 patients were found to have a germline SMARCB1 abnormality. These abnormalities included point and frameshift mutations, intragenic deletions and duplications, and larger deletions including regions both proximal and distal to SMARCB1. There were nine cases that demonstrated parent to child transmission of a mutated copy of SMARCB1. In eight of the nine cases, one or more family members were also diagnosed with rhabdoid tumor or schwannoma, and two of the eight families presented with multiple affected children in a manner consistent with gonadal mosaicism. CONCLUSIONS Approximately one-third of newly diagnosed patients with rhabdoid tumor have an underlying genetic predisposition to tumors due to a germline SMARCB1 alteration. Families may demonstrate incomplete penetrance and gonadal mosaicism, which must be considered when counseling families of patients with rhabdoid tumor.
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Affiliation(s)
- Katherine W. Eaton
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Laura S. Tooke
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Luanne M. Wainwright
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Alexander R. Judkins
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania,Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
| | - Jaclyn A. Biegel
- Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania,Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania,Department of Pediatrics, University of Pennsylvania School of Medicine
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Gonzalvo A, Fowler A, Cook RJ, Little NS, Wheeler H, McDonald KL, Biggs MT. Schwannomatosis, sporadic schwannomatosis, and familial schwannomatosis: a surgical series with long-term follow-up. Clinical article. J Neurosurg 2010; 114:756-62. [PMID: 20932094 DOI: 10.3171/2010.8.jns091900] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECT The aim of this study was to provide disease-specific information about schwannomatosis in its different forms and to present 2 particular cases of malignant schwannomas in the context of familial schwannomatosis (FS). METHODS The authors analyzed patients with pathologically defined schwannomas and identified those with varied forms of schwannomatosis. Each case was retrospectively analyzed for patient sex and age, number of operations and tumors excised, symptoms, location and size of tumors, extent of resection, nerve function pre- and postoperatively, complications, other nonsurgically treated tumors, malignancy, results of brain MR imaging, and follow-up data. RESULTS One hundred fifty-eight patients underwent the excision of 216 schwannomas. One hundred forty-two patients presented with solitary schwannomas, 2 had neurofibromatosis Type 2 (NF2), and 14 presented with schwannomatosis. The average follow-up was 52 months. Six individuals had sporadic schwannomatosis, whereas 8 had the familial form of the disease. These 14 patients had an average age of 28.3 years at the time of disease onset (median 27.5 years) and 35.4 years at the time of the first operation (median 37 years) Thirteen of the 14 patients with schwannomatosis experienced pain as the first symptom. Eight (57%) of the 14 patients presented with at least 1 tumor in the spinal canal or attached to the spinal nerve roots. Malignant schwannomas developed in 2 patients from the same family during the follow-up. CONCLUSIONS Patients suffering from schwannomatosis tend to be younger than those presenting with solitary schwannomas. Therefore, individuals presenting at a young age with multiple schwannomas but not meeting the criteria for NF2 should prompt the physician to suspect schwannomatosis. Patients with schwannomatosis who report pain should be exhaustively examined. The spine is affected in the majority of patients, and MR imaging of the spine should be part of the routine evaluation. Rapid enlargement of schwannomas in the context of FS should raise suspicion of malignant transformation.
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Affiliation(s)
- Augusto Gonzalvo
- Department of Neurosurgery, Royal North Shore Hospital, St. Leonards, New South Wales, Australia.
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