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Fibroblastic/myofibroblastic tumors constitute an important group of soft tissue tumors that are often diagnostically challenging. Recently, major advances have been made in understanding the immunohistochemistry profiles and molecular genetics of fibroblastic/myofibroblastic tumors. Useful immunohistochemical features for tumor diagnosis include loss of retinoblastoma protein expression in mammary-type myofibroblastoma and cellular angiofibroma, nuclear staining for β-catenin in desmoid-type fibromatosis, ALK (anaplastic lymphoma kinase) protein expression in inflammatory myofibroblastic tumors, and MUC4 (mucin 4) expression in low-grade fibromyxoid sarcoma and sclerosing epithelioid fibrosarcoma. Recent findings in the molecular pathology of fibroblastic/myofibroblastic tumors have also contributed significantly to proper diagnoses. Newly identified genetic alterations include the USP-MYH9 fusion gene in nodular fasciitis, the NAB2-STAT6 fusion gene in solitary fibrous tumor, and the TGFBR3-MGEA5 fusion gene in myxoinflammatory fibroblastic sarcoma. Recently, angiofibroma of soft tissue, low-grade myofibroblastic sarcoma, and myxoinflammatory fibroblastic sarcoma have been described. Known tumor entities with new findings include epithelioid inflammatory myofibroblastic sarcoma and epithelioid myxofibrosarcoma. Tumor progression includes cellular angiofibroma with atypia and sarcomatous transformation, fibrosarcomatous dermatofibrosarcoma protuberans, and solitary fibrous tumor with dedifferentiation. The term hemangiopericytoma was removed from the 2013 World Health Organization classification of soft tissue tumors, and giant cell fibroblastoma and dermatofibrosarcoma protuberans were incorporated in the fibroblastic/myofibroblastic category. Myofibroma/myofibromatosis has been categorized as a pericytic (perivascular) tumor.