Mesenchymal tumors of the breast and their mimics : a diagnostic approach

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Preface Contents Contributors 1: Metaplastic Carcinoma of the Breast Introduction Clinical Features Imaging Gross Pathologic Features Specific Histomorphologies of Metaplastic Carcinoma Low-Grade Adenosquamous Carcinoma Microscopic Immunohistochemistry Differential Diagnosis Fibromatosis-like Metaplastic Carcinoma Microscopic Immunohistochemistry Differential Diagnosis Squamous Cell Carcinoma Microscopic Immunohistochemistry Differential Diagnosis Spindle Cell Carcinoma Microscopic Immunohistochemistry Differential Diagnosis Metaplastic Carcinoma with Heterologous Mesenchymal Differentiation Microscopic Immunohistochemistry Differential Diagnosis Mixed Metaplastic Carcinoma Microscopic Molecular Treatment and Prognosis Selected References 2: Phyllodes Tumors Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Selected References 3: Periductal Stromal Hyperplasia and Periductal Stromal Tumor Introduction Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Practical Tips Selected References 4: Vascular Tumors of the Breast Benign Vascular Tumors of the Breast Perilobular Hemangioma Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Hemangiomas Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Angiomatosis Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Intravascular Papillary Endothelial Hyperplasia Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Radiation and Lymphedema-Associated Vascular Tumors Atypical Vascular Lesion Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Prognosis and Treatment Post-Radiation and Lymphedema-Associated Angiosarcoma Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Prognosis and Treatment Primary Angiosarcoma Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Prognosis and Treatment Selected References 5: Mesenchymal Breast Tumors with Fibroblastic and Myofibroblastic Differentiation Myofibroblastoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Desmoid Fibromatosis Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Pseudoangiomatous Stromal Hyperplasia Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Nodular Fasciitis Clinical Features Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Inflammatory Myofibroblastic Tumor Clinical Findings Imaging Pathologic Findings Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Dermatofibrosarcoma Protuberans Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Cellular Dermatofibroma (Cellular Benign Fibrous Histiocytoma) Clinical Features Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Myxoma and Superficial Angiomyxoma Clinical Features Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Primary Breast Sarcomas with Fibroblastic/Myofibroblastic Differentiation Adult Fibrosarcoma and Kinase-Rearranged Spindle Cell Sarcomas Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Myxofibrosarcoma Clinical Features Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Low-Grade Fibromyxoid Sarcoma (Evans Tumor) and Sclerosing Epithelioid Fibrosarcoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Low-Grade Myofibroblastic Sarcoma Clinical Features Imaging Pathological Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Soft Tissue Angiofibroma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Selected References 6: Adipocytic Tumors Reactive Processes with Prominent Fat Fat Necrosis Clinical Features Imaging Pathologic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Benign Adipocytic Tumors Occurring in Breast Lipoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Angiolipoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Hibernoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Liposarcomas Occurring in Breast Atypical Lipomatous Tumor/Well-Differentiated Liposarcoma (ALT/WDL) Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Myxoid Liposarcoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Pleomorphic Liposarcoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Features Differential Diagnosis Treatment and Prognosis Mammary Tumors with Adipocytic Components References 7: Inflammatory Lesions and Inflammatory-Like Lesions Overview Invasive Histiocytoid Carcinoma Introduction Clinical Features Imaging Pathologic Features Gross Features Microscopic Immunohistochemistry Differential Diagnosis Molecular Treatment and Prognosis Practical Tips Cystic Neutrophilic Granulomatous Mastitis Introduction Clinical Features Imaging Pathologic Features Gross Microscopic Immunohistochemistry and Special Stains Molecular Differential Diagnosis Treatment and Prognosis Practical Tips Granular Cell Tumor Introduction Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis IGG4 Sclerosing Mastitis Introduction Clinical Features Imaging Pathologic Features Gross Microscopic Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Extranodal Rosai-Dorfman Disease Introduction Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Prognosis and Treatment Cellular Spindled Histiocytic Pseudotumor Complicating Mammary Fat Necrosis Introduction Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Differential Diagnosis Prognosis and Treatment Selected References 8: Miscellaneous Mesenchymal Tumors of the Breast Solitary Fibrous Tumor Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Ossifying Fibromyxoid Tumor Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Synovial Sarcoma Clinical Features Imaging Pathologic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Perivascular Epithelioid Cell Tumor (PEComa) Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Pleomorphic Hyalinizing Angiectatic Tumor Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Giant Cell Tumor of Soft Tissue Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Extraskeletal Osteosarcoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Myoid Hamartoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Leiomyoma of the Nipple/Areola and Breast Clinical Features Imaging Pathologic Findings Gross Findings Microscopic Findings Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Leiomyosarcoma Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Rhabdomyosarcoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Genetic and Molecular Findings Differential Diagnosis Treatment and Prognosis Sarcomas Metastatic to the Breast Ewing Sarcoma Clinical Microscopic Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Alveolar Soft Part Sarcoma Clinical Microscopic Immunohistochemistry Molecular Differential Diagnosis Epithelioid Sarcoma Clinical Features Imaging Pathologic Features Gross Features Microscopic Features Immunohistochemistry Differential Diagnosis Treatment and Prognosis Myoepithelial Tumors of the Breast Introduction Clinical Features Imaging Pathologic Features Gross features Microscopic features Immunohistochemistry Molecular Differential Diagnosis Treatment and Prognosis Selected References Index This book utilizes a uniform approach to provide a framework for the diagnosis of mesenchymal tumors of the breast while highlighting their mimics. Emphasis is placed on a practical approach to the morphologic interpretation and useful ancillary tests while exploring the differential diagnoses in depth. Given the overall low incidence of mesenchymal lesions of the breast along with their mimics, surgical pathologists are not consistently exposed to these spindle cell lesions. Compounding this problem is the broad differential that these lesions engender, with entities ranging from reactive/reparative lesions to poorly differentiated spindle cell malignancies. Furthering the challenge, the diagnoses may be complicated by fixation issues, sampling method, small sample size, lack of clinical history and prior treatment effects. The goal of this book is to introduce readers to the spectrum of these lesions while providing a systematic approach that helps establish accurate diagnoses that in turn drive appropriate clinical follow up and treatment. Chapters cover the spectrum of benign and malignant mesenchymal tumors and their mimics that are found in the breast in an easy to read format with richly detailed images to aid in diagnoses. The text also discusses practical components to aid in establishing and evaluating the differential diagnosis. Given how morphologically and clinically diverse these lesions are, Mesenchymal Tumors of the Breast and Their Mimics provides a construct for integrating the varied components that go into establishing a diagnosis for this challenging aspect of breast pathology.