Imaging features, staging system, and surgical management of giant cell lesions of the temporal bone

Background Giant cell tumors (GCTs) and giant cell granulomas (GCGs) are giant cell-rich lesions that occur extremely rarely in the temporal bone and have similar clinical presentations. Objectives We aimed to analyze the clinical features and introduce our staging system and surgical treatment. Methods Forty-six patients pathologically diagnosed with a giant cell lesion involving the temporal bone between October 2001 and October 2020 were reviewed retrospectively. The clinical characteristics, surgical approaches, and risk factors for recurrence were analyzed. Results GCTs and GCGs presented as masses centered on the temporomandibular joint with similar imaging features, including a thin, calcified shell and central scattered calcifications on a computed tomography scan. Differences were detected on magnetic resonance imaging in 29.6% (4/14) of GCG and 50% (16/32) of GCT cases; the remaining cases were not distinguishable. Based on our staging system and surgical strategy, 31.8% (7/22) of GCT and 10% (1/10) of GCG cases experienced recurrence, which compares to recurrence rates of 60% in GCT cases and 20% in GCG cases in previous studies. Conclusions Specific clinical and preoperative imaging features help to make a diagnosis of temporal giant cell-rich lesions. Our staging system and surgical strategy could help surgeons tailor the surgical strategy.