Adverse event risks and prognostic factors associated with endoscopic laryngopharyngeal surgery for superficial head and neck cancer after chemoradiotherapy

Abstract Background Endoscopic laryngopharyngeal surgery (ELPS) is an organ-preserving treatment for superficial head and neck squamous cell carcinoma (sHNSCC). While ELPS shows favorable outcomes in primary and metachronous lesions, its role as salvage treatment following chemoradiotherapy (CRT) remains unclear. We evaluated the clinical outcomes of salvage ELPS and factors associated with adverse events (AEs) and prognosis. Methods Among 136 patients undergoing ELPS between 2014 and 2024, we retrospectively analyzed 17 diagnosed with sHNSCC following CRT. Patients were categorized into salvage and metachronous groups, and clinical characteristics, treatment outcomes, AEs, and survival were compared. Results The en bloc resection rate was 100%. AEs occurred in 47.1% of patients and were more frequent in the salvage group than in the metachronous group (70.0% vs. 14.3%, p =0.024). Body mass index (BMI) <18.5 kg/m 2 was significantly associated with AEs ( p =0.043). 4-year overall survival (OS) did not differ significantly between groups (83.3% vs. 71.4%), while 12-month relapse-free survival tended to be lower in the salvage group (68.6% vs. 85.7%). BMI was also associated with OS: patients with BMI ≥18.5 kg/m 2 had a 4-year OS of 81.8%, compared with 50% for patients with BMI <18.5 kg/m 2 ( p =0.036). Conclusion Salvage ELPS for sHNSCC was associated with a higher AE risk but showed long-term survival outcomes comparable to metachronous ELPS. Nutritional status, particularly low BMI, is a key determinant of safety and prognosis. These findings support the feasibility of ELPS as an organ-preserving strategy and emphasize the importance of careful patient selection and nutritional assessment in salvage settings.