Post‐irradiation nasal nitric oxide in patients with nasopharyngeal carcinoma

nNO levels decreased at 3 and 6 months and recovered at 12 months after radiotherapy in NPC. nNO may be a feasible biomarker for mucociliary function in post-irradiated NPC patients. Lower nNO levels were associated with more sinonasal burdens in post-irradiated NPC patients.