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Ivan Chebib - One of the best experts on this subject based on the ideXlab platform.
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Histone H3K27 dimethyl loss is highly specific for malignant peripheral Nerve Sheath Tumor and distinguishes true PRC2 loss from isolated H3K27 trimethyl loss
Modern Pathology, 2019Co-Authors: Dylan M. Marchione, Ana B Larque, Ivan Chebib, Amanda Lisby, Angela N. Viaene, Mariarita Santi, Maclean Nasrallah, Li-ping Wang, Erik A. Williams, Benjamin A. GarciaAbstract:Malignant peripheral Nerve Sheath Tumors contain loss of histone H3K27 trimethylation (H3K27me3) due to driver mutations affecting the polycomb repressive complex 2 (PRC2). Consequently, loss of H3K27me3 staining has served as a diagnostic marker for this Tumor type. However, recent reports demonstrate H3K27me3 loss in numerous other Tumors, including some in the differential diagnosis of malignant peripheral Nerve Sheath Tumor. Since these Tumors lose H3K27me3 through mechanisms distinct from PRC2 loss, we set out to determine whether loss of dimethylation of H3K27, which is also catalyzed by PRC2, might be a more specific marker of PRC2 loss and malignant peripheral Nerve Sheath Tumor. Using mass spectrometry, we identify a near complete loss of H3K27me2 in malignant peripheral Nerve Sheath Tumors and cell lines. Immunohistochemical analysis of 72 malignant peripheral Nerve Sheath Tumors, seven K27M-mutant gliomas, 43 ependymomas, and 10 Merkel cell carcinomas demonstrates that while H3K27me3 loss is common across these Tumor types, H3K27me2 loss is limited to malignant peripheral Nerve Sheath Tumors and is highly concordant with H3K27me3 loss (33/34 cases). Thus, increased specificity does not come at the cost of greatly reduced sensitivity. To further compare H3K27me2 and H3K27me3 immunohistochemistry, we investigated 42 melanomas and 54 synovial sarcomas, histologic mimics of malignant peripheral Nerve Sheath Tumor with varying degrees of H3K27me3 loss in prior reports. While global H3K27me3 loss was not seen in these Tumors, weak and limited H3K27me3 staining was common. By contrast, H3K27me2 staining was more clearly retained in all cases, making it a superior binary classifier. This was confirmed by digital image analysis of stained slides. Our findings indicate that H3K27me2 loss is highly specific for PRC2 loss and that PRC2 loss is a rarer phenomenon than H3K27me3 loss. Consequently, H3K27me2 loss is a superior diagnostic marker for malignant peripheral Nerve Sheath Tumor.
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Synovial sarcoma mimicking benign peripheral Nerve Sheath Tumor
Skeletal Radiology, 2017Co-Authors: Ana B Larque, Miriam A Bredella, G. Petur Nielsen, Ivan ChebibAbstract:Objective To assess the radiographic and clinicopathologic features of synovial sarcoma of the Nerve that were clinically or radiologically interpreted as benign peripheral Nerve Sheath Tumor. Materials and methods Five patients with synovial sarcoma arising from the peripheral Nerve and interpreted clinically and radiologically as peripheral Nerve Sheath Tumors were identified. Clinicopathologic and imaging features were evaluated. Results There were three females and two males, ranging in age from 28 to 50 (mean 35.8) years. Most patients (4/5) complained of a mass, discomfort or pain. MR images demonstrated a heterogeneous, enhancing, soft tissue mass contiguous with the neurovascular bundle. On histologic examination, most Tumors were monophasic synovial sarcoma (4/5). At the time of surgery, all Tumors were noted to arise along or within a peripheral Nerve. All patients were alive with no evidence of disease with median follow-up of 44 (range 32–237) months. For comparison, approximately 775 benign peripheral Nerve Sheath Tumors of the extremities were identified during the same time period. Conclusions Primary synovial sarcoma of the Nerve can mimic peripheral Nerve Sheath Tumors clinically and on imaging and should be included in the differential diagnosis for Tumors arising from peripheral Nerves.
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synovial sarcoma mimicking benign peripheral Nerve Sheath Tumor
Skeletal Radiology, 2017Co-Authors: Ana B Larque, Miriam A Bredella, Petur G Nielsen, Ivan ChebibAbstract:Objective To assess the radiographic and clinicopathologic features of synovial sarcoma of the Nerve that were clinically or radiologically interpreted as benign peripheral Nerve Sheath Tumor.
Brian P Rubin - One of the best experts on this subject based on the ideXlab platform.
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superficial malignant peripheral Nerve Sheath Tumor
American Journal of Clinical Pathology, 2005Co-Authors: Kimberly H Allison, Rajiv M Patel, John R Goldblum, Brian P RubinAbstract:We reviewed the clinicopathologic features of 5 cases of malignant peripheral Nerve Sheath Tumor (MPNST) manifesting in superficial locations associated with cutaneous neurofibromas (4 cases) or superficial peripheral Nerve (1 case). Four cases had spindle cell morphologic features and were at least focally positive for S-100 protein, whereas the associated benign neural elements had more extensive S-100 immunoreactivity. The single epithelioid case was diffusely and strongly positive for S-100 protein. Melanoma markers, epithelial membrane antigen, glial fibrillary acidic protein, neurofilament, pancytokeratin (AE1/AE3), CD34, smooth muscle actin, and desmin were negative in all cases. There were no local recurrences, but 3 patients died of metastatic disease within 2 to 30 months (median, 21 months). MPNSTs can occur in a superficial location and may have an aggressive clinical course. Immunohistochemical markers are helpful in excluding other lesions in the differential diagnosis. However, identification of a benign precursor or origin from a Nerve may be the most definitive way to properly classify these rare lesions.
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superficial malignant peripheral Nerve Sheath Tumor a rare and challenging diagnosis
American Journal of Clinical Pathology, 2005Co-Authors: Kimberly H Allison, Rajiv M Patel, John R Goldblum, Brian P RubinAbstract:We reviewed the clinicopathologic features of 5 cases of malignant peripheral Nerve Sheath Tumor (MPNST) manifesting in superficial locations associated with cutaneous neurofibromas (4 cases) or superficial peripheral Nerve (1 case). Four cases had spindle cell morphologic features and were at least focally positive for S-100 protein, whereas the associated benign neural elements had more extensive S-100 immunoreactivity. The single epithelioid case was diffusely and strongly positive for S-100 protein. Melanoma markers, epithelial membrane antigen, glial fibrillary acidic protein, neurofilament, pancytokeratin (AE1/AE3), CD34, smooth muscle actin, and desmin were negative in all cases. There were no local recurrences, but 3 patients died of metastatic disease within 2 to 30 months (median, 21 months). MPNSTs can occur in a superficial location and may have an aggressive clinical course. Immunohistochemical markers are helpful in excluding other lesions in the differential diagnosis. However, identification of a benign precursor or origin from a Nerve may be the most definitive way to properly classify these rare lesions.
Ana B Larque - One of the best experts on this subject based on the ideXlab platform.
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Histone H3K27 dimethyl loss is highly specific for malignant peripheral Nerve Sheath Tumor and distinguishes true PRC2 loss from isolated H3K27 trimethyl loss
Modern Pathology, 2019Co-Authors: Dylan M. Marchione, Ana B Larque, Ivan Chebib, Amanda Lisby, Angela N. Viaene, Mariarita Santi, Maclean Nasrallah, Li-ping Wang, Erik A. Williams, Benjamin A. GarciaAbstract:Malignant peripheral Nerve Sheath Tumors contain loss of histone H3K27 trimethylation (H3K27me3) due to driver mutations affecting the polycomb repressive complex 2 (PRC2). Consequently, loss of H3K27me3 staining has served as a diagnostic marker for this Tumor type. However, recent reports demonstrate H3K27me3 loss in numerous other Tumors, including some in the differential diagnosis of malignant peripheral Nerve Sheath Tumor. Since these Tumors lose H3K27me3 through mechanisms distinct from PRC2 loss, we set out to determine whether loss of dimethylation of H3K27, which is also catalyzed by PRC2, might be a more specific marker of PRC2 loss and malignant peripheral Nerve Sheath Tumor. Using mass spectrometry, we identify a near complete loss of H3K27me2 in malignant peripheral Nerve Sheath Tumors and cell lines. Immunohistochemical analysis of 72 malignant peripheral Nerve Sheath Tumors, seven K27M-mutant gliomas, 43 ependymomas, and 10 Merkel cell carcinomas demonstrates that while H3K27me3 loss is common across these Tumor types, H3K27me2 loss is limited to malignant peripheral Nerve Sheath Tumors and is highly concordant with H3K27me3 loss (33/34 cases). Thus, increased specificity does not come at the cost of greatly reduced sensitivity. To further compare H3K27me2 and H3K27me3 immunohistochemistry, we investigated 42 melanomas and 54 synovial sarcomas, histologic mimics of malignant peripheral Nerve Sheath Tumor with varying degrees of H3K27me3 loss in prior reports. While global H3K27me3 loss was not seen in these Tumors, weak and limited H3K27me3 staining was common. By contrast, H3K27me2 staining was more clearly retained in all cases, making it a superior binary classifier. This was confirmed by digital image analysis of stained slides. Our findings indicate that H3K27me2 loss is highly specific for PRC2 loss and that PRC2 loss is a rarer phenomenon than H3K27me3 loss. Consequently, H3K27me2 loss is a superior diagnostic marker for malignant peripheral Nerve Sheath Tumor.
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Synovial sarcoma mimicking benign peripheral Nerve Sheath Tumor
Skeletal Radiology, 2017Co-Authors: Ana B Larque, Miriam A Bredella, G. Petur Nielsen, Ivan ChebibAbstract:Objective To assess the radiographic and clinicopathologic features of synovial sarcoma of the Nerve that were clinically or radiologically interpreted as benign peripheral Nerve Sheath Tumor. Materials and methods Five patients with synovial sarcoma arising from the peripheral Nerve and interpreted clinically and radiologically as peripheral Nerve Sheath Tumors were identified. Clinicopathologic and imaging features were evaluated. Results There were three females and two males, ranging in age from 28 to 50 (mean 35.8) years. Most patients (4/5) complained of a mass, discomfort or pain. MR images demonstrated a heterogeneous, enhancing, soft tissue mass contiguous with the neurovascular bundle. On histologic examination, most Tumors were monophasic synovial sarcoma (4/5). At the time of surgery, all Tumors were noted to arise along or within a peripheral Nerve. All patients were alive with no evidence of disease with median follow-up of 44 (range 32–237) months. For comparison, approximately 775 benign peripheral Nerve Sheath Tumors of the extremities were identified during the same time period. Conclusions Primary synovial sarcoma of the Nerve can mimic peripheral Nerve Sheath Tumors clinically and on imaging and should be included in the differential diagnosis for Tumors arising from peripheral Nerves.
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synovial sarcoma mimicking benign peripheral Nerve Sheath Tumor
Skeletal Radiology, 2017Co-Authors: Ana B Larque, Miriam A Bredella, Petur G Nielsen, Ivan ChebibAbstract:Objective To assess the radiographic and clinicopathologic features of synovial sarcoma of the Nerve that were clinically or radiologically interpreted as benign peripheral Nerve Sheath Tumor.
Michel Kliot - One of the best experts on this subject based on the ideXlab platform.
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resection of a benign brachial plexus Nerve Sheath Tumor using intraoperative electrophysiological monitoring
Neurosurgery, 2007Co-Authors: Keith Kwok, Brooke Davis, Michel KliotAbstract:OBJECTIVE: Benign peripheral Nerve Sheath Tumors arising from the brachial plexus are rare. Neurosurgeons often lack the clinical and surgical experience to optimize the management of these uncommon Tumors. We filmed a video depicting the surgical resection of a benign peripheral Nerve Sheath Tumor involving the brachial plexus. METHODS: An illustrative case was used to demonstrate the proper management of a brachial plexus Nerve Sheath Tumor including the important role of intraoperative electrophysiological neuromonitoring during Tumor resection. RESULTS: Using an illustrative case, we describe a systematic approach in the evaluation and surgical management of patients with a brachial plexus Nerve Sheath Tumor. The importance of taking a thorough clinical history, performing a thorough physical examination, applying high-resolution magnetic resonance imaging techniques to visualize the pathology, and using intraoperative electrophysiological neuromonitoring during surgical exposure and resection of the Tumor are stressed. Combined with appropriate postoperative treatment, these techniques minimize the risks and increase the likelihood of achieving a good clinical outcome. CONCLUSION: Brachial plexus Nerve Sheath Tumors are challenging mass lesions that should be evaluated and surgically resected by an experienced team of physicians to optimize clinical outcome.
Kimberly H Allison - One of the best experts on this subject based on the ideXlab platform.
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superficial malignant peripheral Nerve Sheath Tumor
American Journal of Clinical Pathology, 2005Co-Authors: Kimberly H Allison, Rajiv M Patel, John R Goldblum, Brian P RubinAbstract:We reviewed the clinicopathologic features of 5 cases of malignant peripheral Nerve Sheath Tumor (MPNST) manifesting in superficial locations associated with cutaneous neurofibromas (4 cases) or superficial peripheral Nerve (1 case). Four cases had spindle cell morphologic features and were at least focally positive for S-100 protein, whereas the associated benign neural elements had more extensive S-100 immunoreactivity. The single epithelioid case was diffusely and strongly positive for S-100 protein. Melanoma markers, epithelial membrane antigen, glial fibrillary acidic protein, neurofilament, pancytokeratin (AE1/AE3), CD34, smooth muscle actin, and desmin were negative in all cases. There were no local recurrences, but 3 patients died of metastatic disease within 2 to 30 months (median, 21 months). MPNSTs can occur in a superficial location and may have an aggressive clinical course. Immunohistochemical markers are helpful in excluding other lesions in the differential diagnosis. However, identification of a benign precursor or origin from a Nerve may be the most definitive way to properly classify these rare lesions.
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superficial malignant peripheral Nerve Sheath Tumor a rare and challenging diagnosis
American Journal of Clinical Pathology, 2005Co-Authors: Kimberly H Allison, Rajiv M Patel, John R Goldblum, Brian P RubinAbstract:We reviewed the clinicopathologic features of 5 cases of malignant peripheral Nerve Sheath Tumor (MPNST) manifesting in superficial locations associated with cutaneous neurofibromas (4 cases) or superficial peripheral Nerve (1 case). Four cases had spindle cell morphologic features and were at least focally positive for S-100 protein, whereas the associated benign neural elements had more extensive S-100 immunoreactivity. The single epithelioid case was diffusely and strongly positive for S-100 protein. Melanoma markers, epithelial membrane antigen, glial fibrillary acidic protein, neurofilament, pancytokeratin (AE1/AE3), CD34, smooth muscle actin, and desmin were negative in all cases. There were no local recurrences, but 3 patients died of metastatic disease within 2 to 30 months (median, 21 months). MPNSTs can occur in a superficial location and may have an aggressive clinical course. Immunohistochemical markers are helpful in excluding other lesions in the differential diagnosis. However, identification of a benign precursor or origin from a Nerve may be the most definitive way to properly classify these rare lesions.