[Clinical analysis of endoscopic transnasal resection of skull base chondrosarcoma]

Objective:To explore the surgical techniques and clinical outcomes of endoscopic transnasal approaches in the treatment of skull base chondrosarcomas. Methods:Data from patients diagnosed with skull base chondrosarcomas and treated via endoscopic transnasal surgery at the Department of Otorhinolaryngology and Head and Neck Surgery, Xuanwu Hospital, Capital Medical University, from 2013 to 2022 were collected. This retrospective study analyzed the patients' clinical presentations, histopathological grading, involved sites and extents, and complications following the endoscopic transnasal surgery. Disease-free survival rates were calculated using the Kaplan-Meier method. Results:Complete data from 31 patients showed that the primary tumor site was in the petroclival region in 27 cases（87%）, and the anterior skull base in 4 cases（13%）. Pathological grades were Grade Ⅰ（12 cases）, Grade Ⅱ（16 cases）, and Grade Ⅲ（3 cases）. Total resection was achieved in 25 cases, with residual disease post-surgery in 6 cases. The average follow-up duration was 35.7 months（ranging from 6 to 120 months）. Among those who achieved complete resection, recurrence occurred in 5 cases（5/25）, with a five-year disease-free survival rate of 80%. Postoperative complications included transient abducens nerve palsy in 6 patients and cerebrospinal fluid rhinorrhea in 4 patients. There were no cases of death or permanent cranial nerve palsy. Total resection rate（P=0.001） and involvement of the cerebellopontine angle and jugular foramen（P=0.037） were identified as independent risk factors for residual disease and recurrence of chondrosarcoma. Conclusion:The endoscopic transnasal approach is a safe and feasible treatment option for skull base chondrosarcomas.