Pigmented villonodular synovitis of the temporomandibular joint: a case report and the literature review.

Pigmented villonodular synovitis (PVNS) is an uncommon benign proliferative disorder of synovium that may involve joints, tendon sheaths, and bursae. It most often affects the knees, and less frequently involves other joints. It presents in the temporomandibular joints (TMJs) extremely rarely. The authors report an elderly female patient with PVNS of the TMJ with skull base extension, who had traumatic history in the same site. It was diagnosed through core-needle biopsy, which was not documented in the literature. Radical excision and follow-up for 7-8 years was recommended because of the reported malignant transformation and high recurrence rate. This case and previously reported cases in the literature are reviewed and discussed.