A primary osteosarcoma of the mandibular articular process with long-term follow-up: A case report

Primary neoplastic lesions of the temporomandibular joint (TMJ) are rare, with malignant tumors in this region being even more uncommon. The prognosis of maxillofacial malignancies is often poor due to challenges in achieving an adequate surgical margin. Heein, we report a case of TMJ osteosarcoma with an exceptional 34-year disease-free survival following surgery. A 26-year-old patient underwent preoperative chemotherapy and radiation therapy, followed by surgical resection and adjuvant postoperative radiation therapy. Despite significant postoperative cheek deformity, the patient remained free of recurrence or metastasis. We propose that the favorable outcome may be attributed to complete tumor resection facilitated by the TMJ joint capsule, which may have acted as a barrier to tumor spread. This case highlights the potential protective role of the joint capsule in achieving successful outcomes in TMJ osteosarcoma.