Diffuse-type Tenosynovial Giant Cell Tumor Invading the Temporal Bone: Three Cases.

Diffuse-type tenosynovial giant cell tumor (D-TSGCT) is a destructive benign tumor-like proliferative disease that occurs in synovial tissue characterized by villous nodular hyperplasia of joints, tendon sheaths, and synovium. D-TSGCT invading the temporal bone originating from the temporomandibular joint (TMJ) is very rare. Here, we report 3 cases of temporal bone D-TSGCT originating from the TMJ. The tumors in the three cases were originating from the TMJ and further invading the middle ear, the carotid foramen or the temporal lobe respectively. The second patient clearly involved the carotid foramen. The third patient clearly affected the temporal lobe. Lesions were completely removed in 3 cases, and all 3 patients were followed up for 30, 20, and 7 months, and none had recurrence. There are very few reports describing such cases. Although this report is not representative of most scenarios, there is still a potential that it provides a relatively reliable surgical idea for similar cases.