Calcified Chondroid Mesenchymal Neoplasm of the Temporomandibular Joint: A Rare and Recently Described Benign Tumor

The calcified chondroid mesenchymal neoplasm (CCMN) was first recognized as a distinct pathologic entity in 2021 at the University of Washington, and fewer than 100 cases of CCMN have been described in the literature. The CCMN tumor is characterized by the presence of chondroid matrix elements with an FN1–receptor TK gene fusion. CCMNs frequently arise in the distal extremity joints, but less commonly, they have been known to involve the temporomandibular joint (TMJ). This report details the workup and treatment of a patient with a locally advanced CCMN of the TMJ. Our case highlights the diagnostic challenges, radiographic and histological features, and treatment considerations for TMJ CCMN.