{"title":"Cutaneous FUS::TFCP2-Rearranged Rhabdomyosarcoma Initially Misdiagnosed as ALK-Rearranged Mesenchymal Neoplasm: A Case Report.","authors":"Daigo Shiraishi, Kenji Murata, Junya Shimizu, Yasutaka Murahashi, Taro Sugawara, Shintaro Sugita, Makoto Emori, Atsushi Teramoto","doi":"10.1111/cup.14869","DOIUrl":null,"url":null,"abstract":"<p><p>FUS::TFCP2-rearranged rhabdomyosarcoma is a recently identified malignant neoplasm characterized by immunohistochemical evidence of the co-expression of rhabdomyoblastic markers and ALK. Herein, we report a case of cutaneous spindle cell/sclerosing rhabdomyosarcoma with FUS::TFCP2 fusion that was initially interpreted as an ALK-rearranged mesenchymal neoplasm in a 43-year-old male due to negative desmin expression, a rhabdomyoblastic marker. RNA sequencing was performed to detect ALK fusion counterparts; however, no ALK counterpart fusion was observed, and FUS::TFCP2 fusion was detected. Myogenin was negative, but MyoD1 was positive. Detection of FUS signals using FISH led to the diagnosis of FUS::TFCP2-rearranged rhabdomyosarcoma. In cases of ALK positivity and spindle cell or epithelioid cell morphology, FUS::TFCP2-rearranged rhabdomyosarcoma should be considered in the differential diagnosis using staining for rhabdomyoblastic markers other than desmin.</p>","PeriodicalId":15407,"journal":{"name":"Journal of Cutaneous Pathology","volume":" ","pages":""},"PeriodicalIF":1.1000,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Cutaneous Pathology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1111/cup.14869","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"DERMATOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
FUS::TFCP2-rearranged rhabdomyosarcoma is a recently identified malignant neoplasm characterized by immunohistochemical evidence of the co-expression of rhabdomyoblastic markers and ALK. Herein, we report a case of cutaneous spindle cell/sclerosing rhabdomyosarcoma with FUS::TFCP2 fusion that was initially interpreted as an ALK-rearranged mesenchymal neoplasm in a 43-year-old male due to negative desmin expression, a rhabdomyoblastic marker. RNA sequencing was performed to detect ALK fusion counterparts; however, no ALK counterpart fusion was observed, and FUS::TFCP2 fusion was detected. Myogenin was negative, but MyoD1 was positive. Detection of FUS signals using FISH led to the diagnosis of FUS::TFCP2-rearranged rhabdomyosarcoma. In cases of ALK positivity and spindle cell or epithelioid cell morphology, FUS::TFCP2-rearranged rhabdomyosarcoma should be considered in the differential diagnosis using staining for rhabdomyoblastic markers other than desmin.
期刊介绍:
Journal of Cutaneous Pathology publishes manuscripts broadly relevant to diseases of the skin and mucosae, with the aims of advancing scientific knowledge regarding dermatopathology and enhancing the communication between clinical practitioners and research scientists. Original scientific manuscripts on diagnostic and experimental cutaneous pathology are especially desirable. Timely, pertinent review articles also will be given high priority. Manuscripts based on light, fluorescence, and electron microscopy, histochemistry, immunology, molecular biology, and genetics, as well as allied sciences, are all welcome, provided their principal focus is on cutaneous pathology. Publication time will be kept as short as possible, ensuring that articles will be quickly available to all interested in this speciality.