Introduction

Zenker’s diverticulum is associated with a significant burden on quality of life and morbidity, predisposing to dysphagia, regurgitation and aspiration pneumonia. This is often a condition that affects senior patients and access to interventions is limited. Surgery has been the preferred option historically due to a lack of alternative options but remains invasive with major potential complications in an already high-risk patient group. Endoscopic approaches offer a minimally invasive alternative treatment option including rigid and flexible diverticulotomy, and the emerging Zenker per-oral endoscopic myotomy (Z-POEM), albeit no superiority has been demonstrated among these techniques.

Aims & Methods

This systematic review and meta-analysis aimed to summarize the efficacy and safety of these endoscopic techniques.A systematic search in Medline, Cochrane and Scopus databases was performed until November 2023. The primary outcome was technical success, defined as the completion of diverticulotomy/myotomy in one session. Secondary outcomes included clinical success which corresponded to the complete resolution of dysphagia or a post-procedure Dakkak and Bennett score ≤ 1. Moreover, the recurrence rates and the overall adverse events were recorded. Subgroup analyses per outcome were performed to discriminate the results depending on the endoscopic approach (Rigid, flexible diverticulotomy and Z-POEM), whereas the comparative studies were meta-analyzed to compare Z-POEM with alternatives. We used a random effects model and the results were reported as percentages for pooled rates and odds ratios (OR) for comparative data with 95% Confidence Intervals (95%CIs).

Results

From 2004 to 2023 twenty-three studies (1357 patients; 40% female; mean age 43-80) were included in our analysis. The cumulative technical success rate was 97.7% (95%CI: 96.9-98.5) with null heterogeneity (I²=0%), and this outcome was preserved in all subgroups. Considering clinical success, the overall pooled rate was 84.8% (95%CI: 80.8-88.8; I²=79.15%) with Z-POEM yielding higher rate [90.4% (95%CI: 87.8-93.1)] with low heterogeneity (I²=11%), in contrast to the alternatives. 8.6% (95%CI: 6.0-11.3; I²: 63.6%) of cases experienced recurrence, with those post-Z-POEM having the lowest rates [5.7% (95%CI: 2.3-9.1; I²:55.68%)] and post-flexible myotomy the highest ones [12.1% (95%CI: 8.0-16.2; I²=36.09%)]. Finally, complications occurred in 8.7% (95%CI: 6.0-11.4; I2=78.08%) with no changes in subgroup analysis. Five studies (759 patients) provided comparative data for Z-POEM and alternatives. Technical success and recurrence rates were similar between comparators [OR:1.38 (95%CI: 0.59-3.23, p=0.5; I2=0%) and OR:0.69 (95%CI: 0.29-1.51, p=0.39; I²=48.71%), respectively], whereas Z-POEM achieved higher clinical success rates [OR:2.38 (95%CI: 1.54-3.68, p<0.001; I²=0%)]

Conclusion

Endoscopic treatment offers high technical success and symptom resolution in patients with Zenker diverticulum, with relatively low prevalence of adverse events and recurrence. Z-POEM offers higher clinical success rates compared to alternatives with optimal homogeneity.