Effectiveness of Flexible Endoscopic Septum Division for Zenker's Diverticulum: A Multicenter Prospective Study in Japan

Background and study aims: Flexible endoscopic septum division (FESD) is an emerging minimally invasive treatment for Zenker's diverticulum (ZD) in Western countries, but no retrospective or prospective cohort studies have been reported in Asia, particularly in Japan. This prospective, multicenter, observational study aimed to assess the outcomes of FESD for ZD in Japan. Patients and methods:This study included patients diagnosed with ZD presenting with dysphagia (Dakkak-Bennett dysphagia score [DBS] of 1-4) who underwent FESD at four Japanese institutions. The primary outcome of this study was the clinical success rate at three months post-FESD. Secondary outcomes included technical success rate, procedure time, hospital length of stay, diverticulum shape, symptom score, and adverse events. Results:The analysis included 23 patients (male: 39.1% [9/23]) with a mean age of 66.3 ± 11.3 years and baseline DBS of 1.5 ± 0.9. The clinical success rate at 3 months postoperatively was 91.3% (21/23). The mean DBS reached 0.2 ± 0.4, at 3 months, which was significantly reduced from baseline (P < 0.001). Adverse events were limited to minor leakage (n=1, 4.3%) and fever (n=1, 4.3%). Two patients reported minor pharyngeal pain (8.7%). Conclusions: In this Japanese cohort, FESD for ZD demonstrated high clinical success rates and low complication rates. These findings support its wider adoption and justify future prospective comparative studies, as well as potentially building a case for insurance reimbursement.