title: Intraneural Extension of Synovial Sarcoma: Exceptional, or Simply Underrecognized?
abstract: Intraneural extension of soft tissue sarcomas is uncommon; it is most frequently seen in malignant peripheral nerve sheath tumor, but its occurrence is exceptional in synovial sarcoma. We describe a case arising extraneurally within the deep soft tissues of the forearm, which recurred and resulted in above-elbow amputation, revealing an unexpected finding of diffuse intraneural extension of tumor within a macroscopically normal major nerve. Despite macroscopic and microscopically clear soft tissue margins, the neoplasm had "traveled" a significant distance intraneurally to involve the neural resection margin. This feature does not appear to have been described before; it highlights the issue of whether intraneural spread of synovial sarcoma might have been previously underrecognized, and we discuss briefly some practical implications.
authors.affiliation: Royal Marsden Hospital, London, UK.
authors.forename: Wen
authors.initials: W
authors.lastname: Ng
authors.affiliation: Royal Marsden Hospital, London, UK khin.thway@rmh.nhs.uk.
authors.forename: Khin
authors.initials: K
authors.lastname: Thway
mesh_terms: D005542:Forearm; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000473:pathology*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D013584:Sarcoma, Synovial / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000473:pathology*
keywords: SS18 gene rearrangement; intraneural extension; intraneural spread; median nerve; synovial sarcoma