Synovial sarcoma of temporomandibular joint -A case report

Introduction: Synovial sarcoma (SS) is a rare highly malignant soft tissue tumor of young adults .It generally develops in close proximity to joints of extremities but contrary to its name, it does not originate from synovial cells but is of mesenchymal origin. Upto 10% of soft tissue sarcomas are synovial sarcomas. SS of the Temporomandibular joint (TMJ) is a very rare entity. Here, we report a case of synovial sarcoma of the tempromandibular joint in a 22 year old male patient. Case report: A Male patient, 22 years of age had a complaint of a painful swelling in the left pre-auricular region since 2 months..CBCT of the left TMJ revealed advanced Osteolytic changes in the left condylar head region. The affected region had an irregular ‘moth-eaten appearance. USG guided FNAC revealed biphasic pattern of malignant cells with both epithelial and stromal elements. Histopathology of the tumor showed a cellular tumor with biphasic appearance. Immunohistochemistry (IHC) results showed positivity for CK (MNF) which is expressed in epithelial elements.70%of the spindle cells expressed TLE-1 positivity and moderate expression for BCL-2 and CD 99. The histomorphological and IHC findings were consistent with the diagnosis of biphasic synovial sarcoma.
Conclusion: Synovial Sarcomas are very rare in the TMJ region. A CBCT investigation can best define the outline of such tumors, degree of bone involvement & destruction. A high index of suspicion along with CBCT and radiological evaluation, FNAC and histopathological assessment usually clinches the diagnosis.

Keywords: Synovial Sarcoma, TMJ, CBCT, Synovium.