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Andrew L Folpe - One of the best experts on this subject based on the ideXlab platform.

  • Malignantperivascular Epithelioid Cell tumor of the uterus
    2020
    Co-Authors: Jonathan S. Bleeker, J. Fernando Quevedo, Andrew L Folpe
    Abstract:

    Perivascular Epithelioid Cell tumors (PEComas) are a rare collection of tumors arising in a wide array of anatomic locations and characterized by a myomelanocytic phenotype. PEComas which occur in non‐classic anatomic distributions are known as perivascular Epithelioid Cell tumor‐not otherwise specified (PEComa‐NOS), and one of the most common primary sites for PEComa‐NOS is the uterus. The risk of aggressive behavior of these tumors has been linked to a number of factors evaluable on pathologic review following initial surgical resection. We report a case of PEComa‐NOS of the uterus with multiple high‐risk features, including frank vascular invasion, with no evidence of recurrent disease 18 months following initial surgical resection.

  • malignant perivascular Epithelioid Cell neoplasm risk stratification and treatment strategies
    Sarcoma, 2012
    Co-Authors: Jonathan S. Bleeker, Fernando J Quevedo, Andrew L Folpe
    Abstract:

    Purpose. Perivascular Epithelioid Cell tumors (PEComas) are a rare collection of tumors characterized by a myomelanocytic phenotype, and PEComas occurring in “nonclassic” anatomic distributions are known as perivascular Epithelioid Cell tumor not otherwise specified (PEComa-NOS). This review aims to compile and analyze cases of PEComa-NOS in an effort to better define their natural history. Design. We evaluated all 234 cases of PEComa-NOS reported in the English literature, extracting information regarding diagnostic features, treatment approaches, and outcomes. Multivariate analysis of a number of variables evaluable on pathologic review was performed to refine preexisting risk stratification criteria. Outcomes for patients receiving nonsurgical treatment are also reported. Results. Primary tumor size ≥5 cm ( ) and a high (1/50 HPF) mitotic rate ( ) were the only factors significantly associated with recurrence following surgical resection. Cytotoxic chemotherapy and radiation therapy have shown little benefit in treating PEComa-NOS; mTOR inhibition is emerging as a treatment option. Conclusion. Progress has been made in understanding the natural history and molecular biology of PEComa-NOS. This review further clarifies risk of recurrence in this disease, allowing clinicians to better risk stratify patients. Further work should focus on applying this knowledge to making treatment decisions for patients with this disease.

  • malignant perivascular Epithelioid Cell tumor of the uterus
    Rare Tumors, 2012
    Co-Authors: Jonathan S. Bleeker, Fernando J Quevedo, Andrew L Folpe
    Abstract:

    Perivascular Epithelioid Cell tumors (PEComas) are a rare collection of tumors arising in a wide array of anatomic locations and characterized by a myomelanocytic phenotype. PEComas which occur in non-classic anatomic distributions are known as perivascular Epithelioid Cell tumor-not otherwise specified (PEComa-NOS), and one of the most common primary sites for PEComa-NOS is the uterus. The risk of aggressive behavior of these tumors has been linked to a number of factors evaluable on pathologic review following initial surgical resection. We report a case of PEComa-NOS of the uterus with multiple high-risk features, including frank vascular invasion, with no evidence of recurrent disease 18 months following initial surgical resection.

  • cd1a immunopositivity in perivascular Epithelioid Cell neoplasms true expression or technical artifact a streptavidin biotin and polymer based detection system immunohistochemical study of perivascular Epithelioid Cell neoplasms and their morphologic
    Human Pathology, 2011
    Co-Authors: William A Ahrens, Andrew L Folpe
    Abstract:

    Summary Perivascular Epithelioid Cell neoplasms comprise a family of rare neoplasms composed of morphologically distinctive perivascular Epithelioid Cells exhibiting a “myomelanocytic” immunophenotype. The distinction of perivascular Epithelioid Cell neoplasms from other tumors with melanocytic and smooth muscle differentiation can be difficult. A recent study has suggested that perivascular Epithelioid Cell neoplasms routinely express CD1a, a Langerhans Cell–associated transmembrane glycoprotein involved in antigen presentation and that expression of this marker may be helpful in the distinction of perivascular Epithelioid Cell neoplasms from various mimics. We evaluated a series of perivascular Epithelioid Cell neoplasms and potential mimics for CD1a expression. A total of 54 cases (27 perivascular Epithelioid Cell neoplasms, 11 leiomyosarcomas, 10 melanomas, 6 clear Cell sarcomas) were evaluated in 2 laboratories (Mayo Clinic Rochester: 31 cases, Carolinas Medical Center: 23 cases). Selected positive cases were retested at Carolinas Medical Center (11 cases) and Mayo Clinic Rochester (10 cases). Mayo Clinic Rochester methods were as follows: MTB1 clone (1:20, Novocastra, Newcastle-upon-Tyne, UK), heat-induced epitope retrieval in EDTA (pH 8.0), and Dako Advance detection system (Dako Corp, Carpinteria, CA) with background-reducing diluent. Carolinas Medical Center methods were as follows: MTB1 clone (1:30; CellMarque, Rocklin, CA), heat-induced epitope retrieval in Medium Cell Conditioner #1 (pH 8.0-9.0), and streptavidin-biotin detection system with diaminobenzidine chromogen, with and without biotin blocking. Scores were as follows: 1+, 5% to 25%; 2+, 26% to 50%; and 3+, more than 51%. Langerhans Cells served as a positive internal control in all tested cases. All Mayo Clinic Rochester cases were negative. Sixteen Carolinas Medical Center perivascular Epithelioid Cell neoplasms (14 renal angiomyolipomas, 1 soft tissue perivascular Epithelioid Cell neoplasm, 1 pulmonary clear Cell “sugar” tumor) showed CD1a immunopositivity (1+: 7 cases; 2+: 7 cases; 3+: 2 cases) when tested without biotin blocking, 11 of these cases were retested with biotin blocking and were negative. All non–perivascular Epithelioid Cell neoplasms were negative. All positive perivascular Epithelioid Cell neoplasms showed cytoplasmic staining only, without membranous staining. Ten Carolinas Medical Center positive perivascular Epithelioid Cell neoplasms were negative when retested a Mayo Clinic Rochester, using a polymer-based detection system. We conclude that perivascular Epithelioid Cell neoplasms do not truly express CD1a in a biologically plausible membranous pattern, but may instead show aberrant cytoplasmic immunopositivity in some laboratories. Close inspection of published photomicrographs of previously reported CD1a-positive perivascular Epithelioid Cell neoplasms shows an identical pattern of cytoplasmic positivity, likely reflecting abundant endogenous biotin within perivascular Epithelioid Cell neoplasm Cells. We do not believe that there is a role for CD1a immunohistochemistry in the differential diagnosis of perivascular Epithelioid Cell neoplasms.

  • perivascular Epithelioid Cell neoplasms pathology and pathogenesis
    Human Pathology, 2010
    Co-Authors: Andrew L Folpe, David J Kwiatkowski
    Abstract:

    This review article summarizes our current understanding of the clinical, pathologic, immunohistochemical, and genetic aspects of perivascular Epithelioid Cell neoplasms, a rare group of related tumors defined by both morphologic and immunophenotypic criteria.

Franco Bonetti - One of the best experts on this subject based on the ideXlab platform.

Guido Martignoni - One of the best experts on this subject based on the ideXlab platform.

Cyril Fisher - One of the best experts on this subject based on the ideXlab platform.

  • malignant perivascular Epithelioid Cell tumour pecoma of soft tissue a unique case
    The American Journal of Surgical Pathology, 2004
    Co-Authors: Gavin C Harris, Thomas A Mcculloch, Graeme Perks, Cyril Fisher
    Abstract:

    Tumours of perivascular Epithelioid Cells (PEComas) are being increasingly reported at visceral and somatic sites. Both benign and malignant variants have been identified, although clinical follow-up is often limited, which prevents meaningful predictions of behavior. We report the case of a malignant soft tissue PEComa with histologically confirmed regional lymph node metastases and radiologically confirmed pulmonary metastases. The light microscopic appearance and immunohistochemical profile (HMB-45, smooth muscle actin positive) and electron microscopic appearance support perivascular Epithelioid Cell differentiation.

Giuseppe Zamboni - One of the best experts on this subject based on the ideXlab platform.

  • Molecular pathology of lymphangioleiomyomatosis and other perivascular Epithelioid Cell tumors.
    Archives of Pathology & Laboratory Medicine, 2010
    Co-Authors: Guido Martignoni, Giuseppe Zamboni, Daniela Reghellin, Stefano Gobbo, Marco Chilosi, Franco Bonetti
    Abstract:

    Abstract Context. Lymphangioleiomyomatosis (LAM) is a cystic lung disease that can be included in the wide group of proliferative lesions named PEComas (perivascular Epithelioid Cell tumors). These...

  • molecular pathology of lymphangioleiomyomatosis and other perivascular Epithelioid Cell tumors
    Archives of Pathology & Laboratory Medicine, 2010
    Co-Authors: Guido Martignoni, Giuseppe Zamboni, Daniela Reghellin, Stefano Gobbo, Marco Chilosi, Franco Bonetti
    Abstract:

    Abstract Context. Lymphangioleiomyomatosis (LAM) is a cystic lung disease that can be included in the wide group of proliferative lesions named PEComas (perivascular Epithelioid Cell tumors). These proliferative tumors are characterized by the coexpression of myogenic and melanogenesis-related markers. In all these lesions, genetic alterations related to the tuberous sclerosis complex (TSC) have been demonstrated. Striking improvements in the understanding of the genetic basis of this autosomal dominant genetic disease are coupled to the understanding of the mechanisms that link the loss of TSC1 (9q34) or TSC2 (16p13.3) genes with the regulation of the Rheb/m-TOR/p70S6K pathway. These data have opened a new era in the comprehension of the pathogenesis of LAM and have also suggested new therapeutic strategies for this potentially lethal disease. Objective. To present and discuss the pathologic and molecular features of LAM within the spectrum of PEComas, providing a rational approach to their diagnosis. Da...

  • perivascular Epithelioid Cell tumor pecoma in the genitourinary tract
    Advances in Anatomic Pathology, 2007
    Co-Authors: Guido Martignoni, Giuseppe Zamboni, Daniela Reghellin, Franco Bonetti
    Abstract:

    Perivascular Epithelioid Cell tumors (PEComas) are mesenchymal tumors composed of histologically, immunohistochemically, ultrastructurally, and genetically distinctive Cells. PEComas have been described in different organs and are considered ubiquitous tumors. In this review we discuss recent informations related to PEComas in the genitourinary tract.

  • the perivascular Epithelioid Cell and related lesions
    Advances in Anatomic Pathology, 1997
    Co-Authors: Franco Bonetti, Guido Martignoni, Giuseppe Zamboni, Erminia Manirin, Romano Colombari, Gian Mario Mariuzzi
    Abstract:

    SummaryA family of lesions composed of a newly characterized and distictive Cell type, called perivascular Epithelioid Cell (PEC), has been identified. This Cell type characteristically shows immunoreactivity with the melanogenesis-marker HMB45. In this review, we summarize the rapidly growing data