Abstract
Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor most commonly seen in young adults and children. We report a case with morphology and immunohistochemistry supporting the diagnosis of synovial sarcoma. On core biopsy, the tumor had spindle cell and epithelioid morphology with a myxoid background. Staining for transducin-like enhancer of split 1 and CD99 were positive; however, subsequent fluorescence in situ hybridization for SYT (SS18, nBAF chromatin remodeling complex subunit) break apart returned negative. Further study showed fluorescence in situ hybridization for EWSR1 (EWS RNA binding protein 1) gene rearrangement, supporting the diagnosis of AFH. The resected specimen showed a predominant spindle cell proliferation along with histiocytoid areas supporting a diagnosis of AFH. This case report highlights the fact that synovial sarcoma and AFH can overlap morphologically and immunohistochemically. When approaching a biopsy specimen with spindle cell morphology, and transducin-like enhancer of split 1, CD99, and epithelial membrane antigen positivity it is important to include AFH in the differential diagnosis.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Applied immunohistochemistry & molecular morphology : AIMM
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
