Li-Fraumeni syndrome presenting with temporomandibular chondroblastic osteosarcoma following recurrent glioma

A man in his 20s with recurrent glioma developed rapid-onset trismus and left temporomandibular swelling. Imaging revealed condylar destruction with a mineralised mass. Initial biopsy suggested chondroblastic osteosarcoma; germline testing confirmed Li-Fraumeni syndrome with a pathogenic TP53 variant. He underwent segmental resection with temporomandibular joint disarticulation, facial-nerve sacrifice and vascularised free fibular flap reconstruction. The case underscores the need for germline testing in young patients with multiple primary malignancies and adherence to oncological principles despite challenging anatomy.