Extra-Articular Diffuse Tenosynovial Giant Cell Tumor of the Temporomandibular Joint-A Case Report

Tenosynovial giant cell tumors are rare proliferative benign lesions, and are more common in the joints of extremities. Two variants have been distinguished: a localized and a diffuse type. Tumors involving the temporomandibular joint are extremely rare and are often associated with diffuse articular destruction. We present a case of purely extra-articular tenosynovial giant cell tumor of the temporomandibular joint in a 41-year-old man. The clinical patterns and imaging features are indolent which present like a localized type, but it is a diffuse type based on operative findings and histopathologic features. Total excision with partial capsulectomy and parotidectomy was done and no local recurrence was observed during an eighteen-month follow-up period. We characterized the clinical and histopathological features and described the imaging tools and fine-needle aspiration cytology used for the differential diagnosis and operative methods along with a review of the literature.