| Autor: |
Valério E; Department of Pathology, A.C. Camargo Cancer Center, São Paulo, Brazil., Furtado Costa JL; Department of Pathology, DASA Laboratories, São Paulo, Brazil., Perez Fraile NM; Department of Clinical Oncology, Santa Paula Hospital, São Paulo, Brazil., Credidio CH; Department of Pathology, DASA Laboratories, São Paulo, Brazil., Taveira Garcia MR; Department of Radiology, DASA Laboratories, São Paulo, Brazil., Neto CS; Pathology and Molecular Diagnostics (GeneOne), DASA Laboratories, São Paulo, Brazil., Costa FD; Department of Pathology, A.C. Camargo Cancer Center, São Paulo, Brazil.; Department of Pathology, DASA Laboratories, São Paulo, Brazil. |
| Abstrakt: |
Rhabdomyosarcoma affects mainly pediatric patients and is currently classified into four categories: embryonal, alveolar, pleomorphic, and spindle cell/sclerosing. Recently, a molecular group of spindle cell/sclerosing rhabdomyosarcoma demonstrated new fusion transcripts involving FET -family genes with TFCP2 . In this report, we describe a rare case of spindle cell/sclerosing rhabdomyosarcoma in a 19-year-old woman, presenting as a destructive lesion involving the condyle of mandible. Next generation sequencing was performed, revealing a FUS::TFCP2 fusion and deletion of ALK gene. Alectinib therapy was initiated, which resulted in a favorable response for 4 months. However, the patient died due progression of the tumor. To make an accurate diagnosis and ensure appropriate patient management, it is necessary to be aware of this variant and use proper immunohistochemical stains when facing malignant mesenchymal bone lesions, expanding its differential diagnosis. |
