A Surgical Map Defining High-Risk Anatomical Boundaries for Salvage Endoscopic Nasopharyngectomy.

OBJECTIVE: Salvage endoscopic nasopharyngectomy has emerged as a viable option for selected patients with recurrent nasopharyngeal carcinoma. However, the absence of an evidence-based anatomical framework to guide surgical decision-making limits optimal patient selection and contributes to postoperative recurrence. METHODS: We retrospectively analyzed 421 patients with recurrent nasopharyngeal carcinoma who underwent salvage endoscopic nasopharyngectomy between January 2012 and December 2023. Tumor invasion patterns were systematically assessed to identify anatomical sites independently associated with local recurrence, which were subsequently integrated into a surgical map defining high-risk anatomical boundaries. RESULTS: With a median follow-up of 46.0 months, the 5-year overall survival and local recurrence-free survival were 79.8% and 68.2%, respectively. Multivariable analysis identified several anatomical regions significantly associated with inferior local recurrence-free survival, including tumor proximity to the internal carotid artery (< 0.5 cm [HR, 2.813; 95% CI, 1.471-5.380]), pterygomaxillary fossa (HR, 3.181; 95% CI, 1.478-6.845), sphenoid sinus (HR, 3.080; 95% CI, 1.307-7.259), posterior cortex of the clivus (HR, 1.906; 95% CI, 1.021-3.560), foramen lacerum (HR, 2.354; 95% CI, 1.281-4.325), and inferior tumor extension below the axis (HR, 4.611; 95% CI, 1.713-12.410). Patients with involvement of these high-risk areas exhibited markedly lower 5-year overall survival (64.3% vs. 85.8%; p < 0.001) and local recurrence-free survival (26.1% vs. 85.1%; p < 0.001) compared with those without high-risk features. Based on these findings, an evidence-based surgical map was constructed. CONCLUSION: We propose a surgical map that defines high-risk anatomical boundaries for salvage endoscopic nasopharyngectomy in recurrent nasopharyngeal carcinoma. This framework provides a practical decision-support tool to improve oncologic outcomes.