Fine-Needle Aspiration Biopsy Diagnosis of “Invasive” Temporomandibular Joint Pigmented Villonodular Synovitis

The clinical and aspiration cytologic details of a case of temporomandibular joint pigmented villonodular synovitis are presented and correlated with imaging, surgical, histopathologic, and clinical follow-up findings; the origin of such lesions is discussed. The lesion originally presented in a 36-year-old, otherwise healthy, white man as a unilateral mass involving the temporal fossa and temporomandibular joint region. The tumor's extent was defined by magnetic resonance imaging and computed tomographic scan; there was destruction of the temporomandibular joint and erosion of the temporal cranial bones by a lesion whose maximum dimensions were estimated by imaging to be 2.75 × 3.25 cm. The lesion was initially sampled and classified by computed tomography–guided fine-needle aspiration biopsy. Following complete resection, the original diagnosis was confirmed with both hematoxylin-eosin–stained paraffin sections and immunohistochemical staining. The patient remains free of disease 7 years postoperatively.