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Takeuchi Y, Arakawa Y, Yokoo H, Mikami Y, Terada Y, Yoshida K, Miyamoto S, Haga H. Intra-cerebellar schwannoma with various degenerative changes: a case report and a systematic review. BMC Neurol 2022; 22:66. [PMID: 35209854 PMCID: PMC8867888 DOI: 10.1186/s12883-022-02596-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/19/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Intra-cranial schwannomas account for less than 8% of brain tumors, among which more than 80% arise from the vestibular nerve. Intra-cerebellar schwannomas are extremely rare. Several cases have been previously reported but without remarkable degenerative changes on histology. CASE PRESENTATION A 61-year-old man presented with worsening disorientation, and an imaging study revealed a cystic lesion (6.5 cm in the largest diameter) in the left hemisphere of the cerebellum accompanied by a mural nodule (2.5 cm) located just inside the skull with enhancement and focal calcification, in addition to hydrocephalus. The lesion was more than 5 mm from the left acoustic nerve. The patient underwent gross total resection. Pathological examination revealed remarkable degenerative changes with various morphological features. Tumor cells were pleomorphic with rich cytoplasm containing numerous eosinophilic granules. Blood vessels and extracellular matrix showed remarkable hyalinization. Immunohistochemical staining revealed that the tumor cells were positive for S-100 protein and negative for Olig2. The tumor was diagnosed as a schwannoma with marked degenerative changes. CONCLUSIONS The present case is discussed with reference to a systematic review of previous reports of intra-cerebellar schwannoma. Intra-cerebellar schwannoma should be included in the differential diagnosis of cystic lesions with heterogeneous histopathological morphology in the cerebellum.
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Affiliation(s)
- Yasuhide Takeuchi
- Department of Diagnostic Pathology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, 606-8507, Kyoto, Japan
| | - Yoshiki Arakawa
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - Hideaki Yokoo
- Department of Human Pathology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Gunma, 371-8511, Maebashi City, Japan
| | - Yoshiki Mikami
- Department of Diagnostic Pathology, Kumamoto University Hospital, 1-1-1 Honjo, Chuo-ku, 860-8556, Kumamoto City, Japan
| | - Yukinori Terada
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Kazumichi Yoshida
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Susumu Miyamoto
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hironori Haga
- Department of Diagnostic Pathology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, 606-8507, Kyoto, Japan
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Jackson C, Linos K, Liu X. Malignant melanotic nerve sheath tumor in pleural effusion: Deceitful cytology with significant repercussions. Diagn Cytopathol 2021; 50:E76-E80. [PMID: 34698454 DOI: 10.1002/dc.24895] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/30/2021] [Accepted: 10/18/2021] [Indexed: 11/11/2022]
Abstract
Malignant melanotic nerve sheath tumor (MMNST) is an exceedingly rare and aggressive neoplasm of Schwann cell origin that has seldom been described in the cytopathology literature. Herein we present a case of a 60-year-old female with a 3.8 cm presacral mass that was diagnosed as a MMNST. A molecular workup demonstrated TERT promoter -124C > T and TET2 Q891* gene mutations. Within 2 years of her initial diagnosis, she had developed widespread metastasis and pleural effusions. A cytologic workup of the pleural fluid revealed clusters of vacuolated epithelioid cells with enlarged nuclei, prominent nucleoli, and occasional multinucleation. The lesional cells were positive for SOX10, S100-protein, Melan-A, and HMB45, while negative for Calretinin, MOC31, and monoclonal CEA. In this clinicopathologic context, a diagnosis of metastatic MMNST was rendered. Awareness of this entity and its clinical presentation, along with a critical understanding of its molecular findings and that of imitators, is crucial in achieving an accurate diagnosis.
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Affiliation(s)
- Christopher Jackson
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.,Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Konstantinos Linos
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.,Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Xiaoying Liu
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.,Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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3
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Solomou G, Dulanka Silva AH, Wong A, Pohl U, Tzerakis N. Extramedullary malignant melanotic schwannoma of the spine: Case report and an up to date systematic review of the literature. Ann Med Surg (Lond) 2020; 59:217-223. [PMID: 33088497 PMCID: PMC7559563 DOI: 10.1016/j.amsu.2020.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/25/2020] [Accepted: 10/04/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Melanotic schwannoma is a rare variant of schwannoma. Extramedullary melanotic schwannoma originates in the vicinity of nerve roots mimicking other intervertebral disc disorders. Therefore, T1 and T2-weighted MRI sequences become an essential tool for diagnosis. Aside from case reports, no large studies exist to provide consensus on the signal intensities in T1 and T2-weighted MR imaging. Moreover, no clear evidence is available to delineate prognosis. Here, a case report is presented together with a subsequent systematic review of the literature regarding this rare entity. CASE DESCRIPTION A 45-year old female presented with a one-year history of insidious onset of neck pain and paraesthesia. Magnetic resonance imaging confirmed an extramedullary lesion along the C6 nerve root with T1-weighted hyperintensity and T2-weighted hypointensity. Despite two surgical decompressions and adjuvant immunotherapy, the patient unfortunately passed away due to metastatic progression. DISCUSSION According to the systematic review conducted, in over half of the cases of extramedullary melanotic schwannoma, there is local reoccurrence and/or distal metastasis. Moreover, in 64.7% and 70.6% of the cases, the T1-weighted image of the lesion appears hyperintense and hypointense on a T2-weighted image, respectively. It is an aggressive variant of schwannoma, one of the most commonly observed extramedullary tumours presenting to neurosurgical practice. CONCLUSION Our results highlight that specific T1 and T2-weighted imaging findings can provide valuable information, enabling early suspicion, influencing the surgical aims and strategy and the timely commencement of relevant immunotherapy. Considering the poor prognosis, early adjuvant therapy with other modalities should be considered.
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Affiliation(s)
- Georgios Solomou
- School of Medicine, Keele University, Staffordshire, UK Hospital Campus, Newcastle Road, Stoke-on-Trent ST4 6QG, UK
| | - Adikarige Haritha Dulanka Silva
- Paediatric Neurosurgery Fellow, Department of Neurosurgery, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Adrianna Wong
- School of Medicine, Keele University, UK Hospital Campus, Newcastle Road, Stoke-on-Trent, Staffordshire, UKST4 6QG, UK
| | - Ute Pohl
- Consultant Neuropathologist, University Hospitals Birmingham NHS Foundation TrustQueen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston Birmingham, B15 2GW, UK
| | - Nikolaos Tzerakis
- Consultant Neurosurgeon, University Hospital of North Midlands, Stoke on Trent, ST4 6QG, UK
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Alamer A, Tampieri D. Brain and spine melanotic schwannoma: A rare occurrence and diagnostic dilemma. Neuroradiol J 2019; 32:335-343. [PMID: 31094649 DOI: 10.1177/1971400919849819] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Melanotic schwannoma (MS) was formerly known as a rare variant of schwannoma. The behavior of MS is unpredictable, with a tendency for recurrence and metastasis. The purpose of this study was to illustrate the imaging characteristics of these rare and misdiagnosed tumors. The prognosis of MS is discussed, along with the importance of follow-up exams to assess for recurrence and metastasis. Furthermore, we compare our results with those previously published on MS in order to have a better understanding of this rare entity. METHODS Three MS cases were encountered between 2008 and 2015 at our institute. All available data were reviewed, including the clinical history, imaging findings, operative notes, and the histopathology results. A follow-up magnetic resonance imaging (MRI) scan was also reviewed up to 23 months post surgery to assess for recurrence. RESULTS Three cases of MS are included: one in the brain and two in the spine. The brain lesion was in the occipital region. The spine lesions were thoracic intramedullary and sacral intradural. All cases were hypointense on T2-weighted imaging. Gross total resection was achieved for all lesions without adjuvant therapy. To date, the brain lesion recurred 15 months after surgery. CONCLUSIONS MS is a rare and distinct entity rather than a variant of schwannoma, and it poses both diagnostic and management dilemmas. Although MS has characteristic MRI features, including T1 and T2 shortening, the preoperative diagnosis is always challenging. Accurate diagnosis is crucial for management planning, including long-term follow-up exams to assess for recurrence and metastasis.
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Affiliation(s)
- Ali Alamer
- 1 Department of Neuroradiology, Montreal Neurological Hospital and Institute, McGill University, Canada.,2 Department of Radiology, Qassim College of Medicine, Qassim University, Saudi Arabia
| | - Donatella Tampieri
- 1 Department of Neuroradiology, Montreal Neurological Hospital and Institute, McGill University, Canada
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Mahato D, Vivas-Buitrago T, Gassie K, Jentoft M, Tavanaiepour D, Quiñones-Hinojosa A. Intracranial melanotic schwannomas: a rare variant with unusual adherent features. J Neurooncol 2017; 136:299-306. [PMID: 29098570 DOI: 10.1007/s11060-017-2653-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/23/2017] [Indexed: 10/18/2022]
Abstract
Intracranial melanotic schwannomas (IMSch) are extremely rare nerve sheath tumors with features of Schwann cells that produce melanin. After a thorough review of the available literature since 1967, we report not only the 20th case of IMSch but a comprehensive modern-era analysis of radiographic and histological key-points to be considered when diagnosing and treating patients with this rare known entity. This is the case of a 43 years-old woman who presented with severe headaches 9 years ago (2008). At that time, MRI of the brain showed a 1.5 × 1.4 cm lesion at the level of the left cerebellar peduncle without any evidence of edema, mass effect or hydrocephalus. Given that the patient was neurologically intact, a conservative management with serial MRIs was recommended. Patient stopped following up due to the absence of symptoms. Over the course of the past year, patient noted mild left sided hearing loss and facial weakness, as well as some balance instability that progressed over the last 3 months. Given the presentation and progression of these signs and symptoms, a new MRI was performed in which considerable growth of the lesion was identified, measuring 2.5 × 2.8 × 2.6 cm with mass effect on the pons and the inferior fourth ventricle. She underwent a far lateral approach without a C1 hemilaminectomy for the resection of this lesion. Final pathology was consistent with a non-psammomatous melanotic schwannoma (NPMS) with areas of necrosis. Besides this case, only two other cases of IMSch with findings of necrosis have been reported in the literature, all of them reporting a subtotal resection. Evaluation of all previously reported cases of IMSch shows a male prevalence with a 1.6:1 male to female ratio. IMSch is radiographically T2 hypointense and can be differentiated from Schwannomas that are classically T2 hyperintense. In this case, only a subtotal resection was feasible due to the tumor's overwhelming inherent attachment to vital structures such as cranial nerves (CN), brainstem, and vasculature. While MSch is considered histologically benign, several factors including localization, surrounding structures, the rate of growth, tumor volume resection and histological necrosis should be considered in determining prognosis and further adjuvant treatment planning.
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Affiliation(s)
- D Mahato
- Department of Neurological Surgery, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - T Vivas-Buitrago
- Department of Neurological Surgery, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - K Gassie
- Department of Neurological Surgery, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - M Jentoft
- Department of Neuro-Pathology, Mayo Clinic, Jacksonville, FL, USA
| | - D Tavanaiepour
- Department of Neurological Surgery, University of Florida, Jacksonville, FL, USA
| | - A Quiñones-Hinojosa
- Department of Neurological Surgery, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA.
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Wang L, Zehir A, Sadowska J, Zhou N, Rosenblum M, Busam K, Agaram N, Travis W, Arcila M, Dogan S, Berger MF, Cheng DT, Ladanyi M, Nafa K, Hameed M. Consistent copy number changes and recurrent PRKAR1A mutations distinguish Melanotic Schwannomas from Melanomas: SNP-array and next generation sequencing analysis. Genes Chromosomes Cancer 2015; 54:463-471. [PMID: 26031761 DOI: 10.1002/gcc.22254] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/26/2015] [Accepted: 02/26/2015] [Indexed: 12/25/2022] Open
Abstract
Melanotic Schwannomas (MS) are rare tumors that share histological features with melanocytic tumors and schwannomas. However, their genetics are poorly understood. To elucidate the genetic characteristics of MS, we performed genome-wide studies in a series of cases. Twelve MS cases were available for the study. Genomic DNAs extracted from formalin-fixed paraffin embedded tumor tissues were subjected to copy number (CN) and allelic imbalance (AI) analysis by Single Nucleotide Polymorphism (SNP)-array and screened for mutations in coding exons of 341 key cancer-associated genes using a hybrid capture-based next-generation sequencing (NGS) assay. Sanger sequencing was used to further verify recurrent mutations detected by NGS study. SNP-array analysis revealed remarkably stereotypic chromosomal abnormalities in MS. Hypodiploidy was common, typically involving monosomies of chromosomes 1, 2, and 17. All 12 samples showed mutations in PRKAR1A gene, including 2 cases with 2 mutations each. The 14 mutations were scattered across PRKAR1A, and most were inactivating mutations. AI on 17q, presenting as loss of heterozygosity with or without CN losses, combined with a PRKAR1A mutation was observed in 9/12 MS cases. The remaining 3 cases included the two samples harboring two mutations in PRKAR1A. MS exhibits a stereotypic pattern of chromosomal losses. In contrast, melanomas are typically characterized by the presence of multiple CN aberrations, without demonstrable differences in the frequency of losses and gains. Inactivation of both alleles of PRKAR1A by "two hits" observed in almost all cases underscores the central role of PRKAR1A in the pathogenesis of this neoplasm. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Lu Wang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Ahmet Zehir
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Justyna Sadowska
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Nengyi Zhou
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Marc Rosenblum
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Klaus Busam
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Narasimhan Agaram
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - William Travis
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Maria Arcila
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Snjezana Dogan
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Michael F Berger
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY.,Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Donavan T Cheng
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Marc Ladanyi
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY.,Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Khedoudja Nafa
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Meera Hameed
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY
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8
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Shanthi V, Ramakrishna BA, Bheemaraju VV, Rao NM, Athota VRM. Spinal meningeal melanocytoma: A rare meningeal tumor. Ann Indian Acad Neurol 2011; 13:308-10. [PMID: 21264144 PMCID: PMC3021939 DOI: 10.4103/0972-2327.74192] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 05/14/2010] [Accepted: 05/15/2010] [Indexed: 12/14/2022] Open
Affiliation(s)
- Vissa Shanthi
- Department of Pathology, Narayana Medical College, Nellore, Andhra Pradesh, India
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9
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Marton E, Feletti A, Orvieto E, Longatti P. Dumbbell-shaped C-2 psammomatous melanotic malignant schwannoma. Case report and review of the literature. J Neurosurg Spine 2007; 6:591-9. [PMID: 17561752 DOI: 10.3171/spi.2007.6.6.14] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The authors present the case of a dumbbell-shaped malignant psammomatous melanotic schwannoma of the upper cervical spine involving the C-2 sensory root. The family of the patient had a history of other malignant stromal tumors, without the Carney complex genetic pattern. The 30-year-old female patient complained of experiencing cervical pain and cervical muscle contractions for 6 months, and was admitted to the hospital. The cervical T1-weighted magnetic resonance (MR) images revealed the presence of a slightly hyperintense C2-3 intra-extradural lesion, moderately enhancing, which had eroded and enlarged the intervertebral foramen. The patient workup also included computed tomography scans and angiography. A posterior approach was used to perform a C2-3 hemilaminectomy, including opening of the dura mater and gross-total removal of the lesion. Histopathological examination of the lesion revealed it to be a malignant psammomatous melanotic schwannoma. The cerebrospinal MR image of the patient obtained at the 12-month follow-up examination demonstrated the presence of tumor progression into the subarachnoid space at the C-3 level. The strong malignancy potential of the lesion must be considered in the future management of the patient, especially due to the presence in the family of other stromal tumors such as gastrointestinal-stromal tumors and malignant melanomas. The authors review all the literature concerning melanotic schwannomas and report 105 cases of melanotic schwannoma that were not related to the Carney complex. The particular focus of their review is on the characteristics of the malignant progression of melanotic schwannoma, such as local recurrences, metastasis, and survival rate.
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Affiliation(s)
- Elisabetta Marton
- Department of Neurosurgery, Padova University, Treviso Hospital Treviso, Italy.
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Zonenshayn M, Edgar MA, Lavyne MH. Removal of a lumbar melanotic schwannoma via the far-lateral approach in a patient with Carney complex. Case report. J Neurosurg 2000; 92:241-5. [PMID: 10763702 DOI: 10.3171/spi.2000.92.2.0241] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The authors describe a patient with Carney's complex who presented with sciatica due to a lumbar nerve root sheath tumor. A far-lateral approach was used to resect a nonpsammomatous melanotic schwannoma. Neurosurgeons surgically treating peripheral nerve sheath tumors should be aware of the features of Carney complex because the extent of the preoperative evaluation and postoperative management of an otherwise routine surgical condition can be significantly affected.
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Affiliation(s)
- M Zonenshayn
- Department of Surgery, Weill Medical College of Cornell University, New York, New York, USA
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Vallat-Decouvelaere AV, Wassef M, Lot G, Catala M, Moussalam M, Caruel N, Mikol J. Spinal melanotic schwannoma: a tumour with poor prognosis. Histopathology 1999; 35:558-66. [PMID: 10583580 DOI: 10.1046/j.1365-2559.1999.00786.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To clarify the prognosis of melanotic schwannoma. This is a rare tumour which is generally considered as a benign lesion, reported in many cases with a short follow-up only. METHODS AND RESULTS Five cases of spinal melanotic schwannoma were retrospectively studied. The tumours were examined using standard histological, immunohistochemical and ultrastructural methods. No features of malignancy (high mitotic count, atypia or necrosis) were found in the primary tumours. The follow-up period ranged from 3 to 7 years. Malignant clinical behaviour was clear-cut in four cases: three patients died from metastases to various sites and one presented several discrete spinal tumours of the same type seven years after the first operation. Only one patient presented no recurrence and was free of disease 6 years after initial diagnosis. The review of 57 cases of the literature (including our cases), showed that 15% of the cases had recurrences and 26.3% were complicated by metastasis. Only 53% of the cases followed for more than 5 years, were free of disease vs. 67.5% of the cases with shorter follow-up. Twenty additional cases had no follow-up. CONCLUSION Appropriate long-term follow-up is required for all melanotic schwannomas, as it may recur or metastasize after more than 5 years, even in the absence of overt malignant histological features.
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