title: Primary orbital synovial sarcoma: A clinicopathologic review with a differential diagnosis and discussion of molecular genetics.
abstract: Synovial sarcoma is a soft-tissue sarcoma of the extremities developing in young adults that has rarely been reported in the orbit. Synovial sarcoma is associated with a unique translocation, resulting in an SYT-SSX fusion gene. We analyze 7 published periocular cases, together with the current one, to gain a better appreciation of the features of the tumor in this location and to compare the findings with those derived from nonophthalmic studies. An inferior orbital mass developed in a 31-year-old woman after experiencing periorbital and hemifacial pain for more than a decade. Radiographically, the mass was circumscribed and displayed coarse internal calcifications. A large but subtotal excision with histopathologic examination disclosed a primitive tumor composed of spindled and ovoid cells. Immunohistochemistry demonstrated positivity for nuclear transducin-like enhancer of split 1 and membranous CD99, typical for synovial sarcoma. Fluorescence in situ hybridization identified a (X,18) translocation in the tumor cells. The patient underwent postoperative adjuvant proton beam radiotherapy with a good response that has been maintained during 1 year of follow-up. Orbital soft-tissue tumors of all types are increasingly identified by their distinctive genetic signatures that offer more specificity than standard immunohistochemical tests.
authors.affiliation: David G. Cogan Laboratory of Ophthalmic Pathology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, USA; Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Stagner
authors.affiliation: David G. Cogan Laboratory of Ophthalmic Pathology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, USA; Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA. Electronic address: Fred_Jakobiec@meei.harvard.edu.
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Jakobiec
authors.affiliation: Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Fay
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008967:Molecular Biology / Q000379:methods*; D015514:Oncogene Proteins, Fusion / Q000235:genetics* / Q000378:metabolism; D009918:Orbital Neoplasms / Q000175:diagnosis* / Q000235:genetics; D013584:Sarcoma, Synovial / Q000175:diagnosis* / Q000235:genetics; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; D015514:Oncogene Proteins, Fusion; C116512:SYT-SSX fusion protein
keywords: SYT-SSX; eye; orbit; round cell tumor; synovial sarcoma; transducin-like enhancer of split 1; translocation