Transoral surgery for hypopharyngeal and laryngeal cancers in Japan: Current status from a nationwide multicenter retrospective study.

[OBJECTIVE] In this nationwide retrospective study, we sought to evaluate the oncologic and functional outcomes and safety of transoral surgery (TOS) for hypopharyngeal and laryngeal squamous cell carcinomas in Japan and to clarify the appropriate indications for various TOS modalities.

[METHODS] Data were obtained from the Head and Neck Cancer Registry of Japan. Patients who underwent transoral or endoscopic resection between 2011 and 2016 were selected. Detailed clinical information was collected from 55 institutions using web-based case report forms. Surgical modalities analyzed included endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), endoscopic laryngopharyngeal surgery (ELPS), transoral laser microsurgery (TLM), and transoral videolaryngoscopic surgery (TOVS).

[RESULTS] In total, 1825 patients were included (hypopharyngeal cancer, 62.5 %; laryngeal cancer, 37.5 %). Most cases (77.5 %) were T1 or lower, and 90.8 % were Stage II or earlier. TLM is predominantly used for glottic cancers, ELPS/ESD for superficial hypopharyngeal lesions, and TOVS for more advanced tumors, reflecting distinct indications for each modality. The 5-year disease-specific survival (DSS), recurrence-free survival (RFS), and overall survival (OS) were 97.1 %, 84.3 %, and 85.4 %, respectively. The laryngeal preservation rate was 98.2 %. Tracheostomy was performed in 5.0 % of cases, mainly for airway protection; major complications, including pneumonia (2.4 %), hemorrhage (1.1 %), fistula formation (0.4 %), and vocal cord fixation (2.6 %), occurred in <3 % of patients. Postoperative functional outcomes were favorable, with persistent dysphagia (Functional Outcome Swallowing Scale stage ≥ 3) in 1.6 % and tube feeding dependence in 1.8 %.

[CONCLUSION] Non-robot-assisted TOS demonstrated excellent oncologic control and functional preservation of the larynx with low complication rates in early-stage hypopharyngeal and laryngeal cancers. Each surgical modality has distinct indications depending on the tumor site, depth of invasion, and institutional expertise. These findings support the use of TOS as a safe and effective treatment option for selected patients. Further procedural standardization and data accumulation are required to refine the indications and facilitate their broader adoption in clinical practice.