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Jia Shen - One of the best experts on this subject based on the ideXlab platform.
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pericytic mimicry in well differentiated liposarcoma atypical lipomatous tumor
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Greg Asatrian, Michelle A. Scott, Vi Nguyen, Paulina Giacomelli, Chia Soo, Kang Ting, Nagesh P Rao, Fritz C. EilberAbstract:Pericytes are modified smooth muscle cells that closely enwrap small blood vessels, regulating and supporting the microvasculature through direct endothelial contact. Pericytes demonstrate a distinct immunohistochemical profile, including expression of smooth muscle actin, CD146, platelet-derived growth factor receptor β, and regulator of G-protein signaling 5. Previously, pericyte-related antigens have been observed to be present among a group of soft tissue tumors with a perivascular growth pattern, including glomus tumor, Myopericytoma, and angioleiomyoma. Similarly, malignant tumor cells have been shown to have a pericyte-like immunoprofile when present in a perivascular location, seen in malignant melanoma, glioblastoma, and adenocarcinoma. Here, we examine well-differentiated liposarcoma specimens, which showed some element of perivascular areas with the appearance of smooth muscle (n = 7 tumors). Immunohistochemical staining was performed for pericyte antigens, including smooth muscle actin, CD146, platelet-derived growth factor receptor β, and regulator of G-protein signaling 5. Results showed consistent pericytic marker expression among liposarcoma tumor cells within a perivascular distribution. MDM2 immunohistochemistry and fluorescence in situ hybridization for MDM2 revealed that these perivascular cells were of tumor origin (7/7 tumors), whereas double immunohistochemical detection for CD31/CD146 ruled out an endothelial cell contribution. These findings further support the concept of pericytic mimicry, already established in diverse malignancies, and its presence in well-differentiated liposarcoma. The extent to which pericytic mimicry has prognostic significance in liposarcoma is as yet unknown.
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the pericyte antigen rgs5 in perivascular soft tissue tumors
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Michelle A. Scott, Chia Soo, Kang Ting, Yuhsin Yen, Sarah M Dry, Bruno Peault, Aaron W JamesAbstract:Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation--although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), Myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), Myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, Myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors.
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pericyte antigens in perivascular soft tissue tumors
International Journal of Surgical Pathology, 2015Co-Authors: Jia Shen, Swati Shrestha, Greg Asatrian, Chia Soo, Kang Ting, Yuhsin Yen, Marco Mravic, Sarah M Dry, Bruno PeaultAbstract:Introduction. Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear line of differentiation, although most are presumed to originate from pericytes or modified perivascular cells. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor (previously termed hemangiopericytoma) was once hypothesized to have pericytic differentiation. Methods. Here, we systematically examine pericyte immunohistochemical markers among glomus tumor (including malignant glomus tumor), Myopericytoma, angioleiomyoma, and solitary fibrous tumor. Immunohistochemical staining and semiquantification was performed using well-defined pericyte antigens, including αSMA, CD146, and PDGFRβ. Results. Glomus tumor and Myopericytoma demonstrate diffuse staining for all pericyte markers, including immunohistochemical reactivity for αSMA, CD146, and PDGFRβ. Malignant glomus tumors all showed some degree of per...
Bruno Peault - One of the best experts on this subject based on the ideXlab platform.
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the pericyte antigen rgs5 in perivascular soft tissue tumors
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Michelle A. Scott, Chia Soo, Kang Ting, Yuhsin Yen, Sarah M Dry, Bruno Peault, Aaron W JamesAbstract:Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation--although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), Myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), Myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, Myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors.
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pericyte antigens in perivascular soft tissue tumors
International Journal of Surgical Pathology, 2015Co-Authors: Jia Shen, Swati Shrestha, Greg Asatrian, Chia Soo, Kang Ting, Yuhsin Yen, Marco Mravic, Sarah M Dry, Bruno PeaultAbstract:Introduction. Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear line of differentiation, although most are presumed to originate from pericytes or modified perivascular cells. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor (previously termed hemangiopericytoma) was once hypothesized to have pericytic differentiation. Methods. Here, we systematically examine pericyte immunohistochemical markers among glomus tumor (including malignant glomus tumor), Myopericytoma, angioleiomyoma, and solitary fibrous tumor. Immunohistochemical staining and semiquantification was performed using well-defined pericyte antigens, including αSMA, CD146, and PDGFRβ. Results. Glomus tumor and Myopericytoma demonstrate diffuse staining for all pericyte markers, including immunohistochemical reactivity for αSMA, CD146, and PDGFRβ. Malignant glomus tumors all showed some degree of per...
Christopher D M Fletcher - One of the best experts on this subject based on the ideXlab platform.
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Myopericytomatosis clinicopathologic analysis of 11 cases with molecular identification of recurrent pdgfrb alterations in Myopericytomatosis and Myopericytoma
The American Journal of Surgical Pathology, 2017Co-Authors: Yin P Hung, Christopher D M FletcherAbstract:Myopericytoma is a benign tumor of concentrically distributed perivascular myoid cells. Its molecular basis and relationship with myofibroma/myofibromatosis and other pericytic tumors are not fully understood. In our consultation/surgical files of over 1000 myopericytic lesions, we identified 11 cases with diffuse dermal/subcutaneous involvement by microscopic Myopericytomatous nodules, a phenomenon we have termed Myopericytomatosis. Myopericytomatosis affected mostly adults (female:male=8:3; median age, 37 y; range, 9 to 63 y) in the lower extremities (foot/ankle, 5; calf, 3; knee, 1; thigh, 1; neck, 1) over months to 25 years, ranging from 1.5 to 11.0 (median, 6.0) cm in size. Histologically, Myopericytomatosis displayed diffuse infiltration by innumerable discrete Myopericytoma/myofibroma-like nodules of bland spindled-to-ovoid cells (smooth muscle actin positive), in a mainly perivascular distribution. No mitoses, atypia, or necrosis was noted. All patients were treated by surgical excision (1 patient also received adjuvant radiation), with margins focally positive in 5 of 6 known cases. Of the 6 cases with follow-up of 0.2 to 13.7 (median, 3.4) years, 1 recurred locally twice, while 5 cases showed no recurrence. Targeted next-generation DNA sequencing identified PDGFRB alterations in all cases of Myopericytomatosis and conventional Myopericytoma tested (5 cases each), including mutations in 4 cases of Myopericytomatosis (N666K in 3; Y562-R565 deletion in 1 case) and 3 Myopericytomas (Y562C, K653E, and splice acceptor deletion in 1 case each), as well as low-level PDGFRB amplification in 2 cases of Myopericytomatosis and 4 Myopericytomas. No BRAF, NOTCH, or GLI1 alterations were detected. In summary, Myopericytomatosis is a rare, strikingly diffuse, but apparently benign variant of Myopericytoma that typically involves superficial soft tissue in adults with innumerable discrete microscopic Myopericytomatous nodules. The strongly activating PDGFRB mutation N666K is noted in Myopericytomatosis, but not in conventional Myopericytoma, suggesting that PDGFRB mutation status may account for their pathogenetic differences. As PDGFRB alterations are present in Myopericytoma/Myopericytomatosis and infantile myofibromatosis/myofibroma, these entities indeed lie within a histogenetic continuum. Identification of PDGFRB alterations suggests tyrosine kinase inhibition as a potential therapeutic strategy in myopericytic neoplasms if needed.
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Nuclear β-Catenin Expression is Frequent in Sinonasal Hemangiopericytoma and Its Mimics
Head and Neck Pathology, 2017Co-Authors: Christopher D M FletcherAbstract:Sinonasal hemangiopericytoma (HPC) is a tumor showing pericytic myoid differentiation and which arises in the nasal cavity and paranasal sinuses. CTNNB1 mutations appear to be a consistent aberration in sinonasal HPC, and nuclear expression of β-catenin has been reported. Our aim was to evaluate the frequency of β-catenin expression in sinonasal HPC and its histologic mimics in the upper aerodigestive tract. Cases were retrieved from the surgical pathology and consultation files. Immunohistochemical staining for β-catenin was performed on 50 soft tissue tumors arising in the sinonasal tract or oral cavity, and nuclear staining was recorded semiquantitatively by extent and intensity. Nuclear reactivity for β-catenin was present in 19/20 cases of sinonasal HPC; 17 showed moderate-to-strong multifocal or diffuse staining, and 2 had moderate focal nuclear reactivity. All solitary fibrous tumors (SFT) (10/10) showed focal-to-multifocal nuclear staining, varying from weak to strong in intensity. Most cases of synovial sarcoma (9/10) showed nuclear β-catenin expression in the spindle cell component, ranging from focal-weak to strong-multifocal. No cases of Myopericytoma (0/10) showed any nuclear β-catenin expression. β-catenin expression is prevalent in sinonasal HPC, but is also frequent in SFT and synovial sarcoma. Our findings indicate that β-catenin is not a useful diagnostic tool in the evaluation of spindle cell tumors with a prominent hemangiopericytoma-like vasculature in the sinonasal tract and oral cavity, and that definitive diagnosis relies on the use of a broader immunohistochemical panel.
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recurrent srf rela fusions define a novel subset of cellular myofibroma Myopericytoma a potential diagnostic pitfall with sarcomas with myogenic differentiation
The American Journal of Surgical Pathology, 2017Co-Authors: Cristina R Antonescu, Lei Zhang, Yunshao Sung, Narasimhan P Agaram, Christopher D M FletcherAbstract:Cellular myofibroblastic tumors other than desmoid-type fibromatosis are often diagnostically challenging due to their relative rarity, lack of known genetic abnormalities, and expression of muscle markers which may be confused with sarcomas with myogenic differentiation. In this study we investigate the molecular alterations of a group of cellular myofibroblastic lesions with in the myofibroma and Myopericytoma spectrum for better subclassification. Two index cases were studied by paired-end RNA sequencing for potential fusion gene discovery. One chest wall soft tissue tumor in a 3-month-old girl case showed a SRF-C3orf62 fusion, while the other, a forearm lesion in an 8-year-old girl, showed a SRF-RELA fusion. Further screening of 42 cellular examples of myofibroma/Myopericytoma by fluorescence in situ hybridization identified additional 8 cases with recurrent SRF gene rearrangements, 6 of them showing identical SRF-RELA fusions. The cohort was composed of 7 females and 3 males, with a wide age range of 3 months to 63 years (mean=17). All tumors showed a densely packed growth of oval to spindle cells with fibrillary eosinophilic cytoplasm, arranged either in intersecting fascicles or with a distinct nested pattern around a rich vascular network. Despite the dense cellularity and variable mitotic activity none of the lesions displayed nuclear pleomorphism or necrosis. All tumors showed coexpression for SMA and desmin, in most cases with a strong and diffuse pattern of staining, while myogenin was consistently negative. No distant metastases were seen in the few cases with follow-up information. A control group of 34 well-characterized myofibroblastic and perivascular tumors, including 10 typical myofibromas and 3 Myopericytomas, were also investigated for SRF gene abnormalities by fluorescence in situ hybridization and were negative. In summary, we report a subset of cellular variants of myofibroma and Myopericytoma showing a smooth muscle-like immunophenotype and harboring recurrent SRF-RELA gene fusions, which mimic sarcomas with myogenic differentiation.
Aaron W James - One of the best experts on this subject based on the ideXlab platform.
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the pericyte antigen rgs5 in perivascular soft tissue tumors
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Michelle A. Scott, Chia Soo, Kang Ting, Yuhsin Yen, Sarah M Dry, Bruno Peault, Aaron W JamesAbstract:Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation--although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), Myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), Myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, Myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors.
Kang Ting - One of the best experts on this subject based on the ideXlab platform.
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pericytic mimicry in well differentiated liposarcoma atypical lipomatous tumor
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Greg Asatrian, Michelle A. Scott, Vi Nguyen, Paulina Giacomelli, Chia Soo, Kang Ting, Nagesh P Rao, Fritz C. EilberAbstract:Pericytes are modified smooth muscle cells that closely enwrap small blood vessels, regulating and supporting the microvasculature through direct endothelial contact. Pericytes demonstrate a distinct immunohistochemical profile, including expression of smooth muscle actin, CD146, platelet-derived growth factor receptor β, and regulator of G-protein signaling 5. Previously, pericyte-related antigens have been observed to be present among a group of soft tissue tumors with a perivascular growth pattern, including glomus tumor, Myopericytoma, and angioleiomyoma. Similarly, malignant tumor cells have been shown to have a pericyte-like immunoprofile when present in a perivascular location, seen in malignant melanoma, glioblastoma, and adenocarcinoma. Here, we examine well-differentiated liposarcoma specimens, which showed some element of perivascular areas with the appearance of smooth muscle (n = 7 tumors). Immunohistochemical staining was performed for pericyte antigens, including smooth muscle actin, CD146, platelet-derived growth factor receptor β, and regulator of G-protein signaling 5. Results showed consistent pericytic marker expression among liposarcoma tumor cells within a perivascular distribution. MDM2 immunohistochemistry and fluorescence in situ hybridization for MDM2 revealed that these perivascular cells were of tumor origin (7/7 tumors), whereas double immunohistochemical detection for CD31/CD146 ruled out an endothelial cell contribution. These findings further support the concept of pericytic mimicry, already established in diverse malignancies, and its presence in well-differentiated liposarcoma. The extent to which pericytic mimicry has prognostic significance in liposarcoma is as yet unknown.
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the pericyte antigen rgs5 in perivascular soft tissue tumors
Human Pathology, 2016Co-Authors: Jia Shen, Swati Shrestha, Michelle A. Scott, Chia Soo, Kang Ting, Yuhsin Yen, Sarah M Dry, Bruno Peault, Aaron W JamesAbstract:Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation--although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), Myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), Myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, Myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors.
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pericyte antigens in perivascular soft tissue tumors
International Journal of Surgical Pathology, 2015Co-Authors: Jia Shen, Swati Shrestha, Greg Asatrian, Chia Soo, Kang Ting, Yuhsin Yen, Marco Mravic, Sarah M Dry, Bruno PeaultAbstract:Introduction. Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear line of differentiation, although most are presumed to originate from pericytes or modified perivascular cells. Among these, glomus tumor, Myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor (previously termed hemangiopericytoma) was once hypothesized to have pericytic differentiation. Methods. Here, we systematically examine pericyte immunohistochemical markers among glomus tumor (including malignant glomus tumor), Myopericytoma, angioleiomyoma, and solitary fibrous tumor. Immunohistochemical staining and semiquantification was performed using well-defined pericyte antigens, including αSMA, CD146, and PDGFRβ. Results. Glomus tumor and Myopericytoma demonstrate diffuse staining for all pericyte markers, including immunohistochemical reactivity for αSMA, CD146, and PDGFRβ. Malignant glomus tumors all showed some degree of per...
