Evolution of the Endoscopic Modified Lothrop Procedure: A Systematic Review and Meta-Analysis

Objective: Since first described in the 1990s, the endoscopic modified Lothrop procedure (EMLP) has been the subject of a growing body of literature. We performed a review to compare indications and outcomes of EMLP in an early cohort of publications (1990-2008) versus a contemporary cohort (2009-2016) and compare outcomes associated with follow-up >= 2 years versus <2 years. Data Sources: PubMed, SCOPUS and Cochrane databases. Review Methods: An English-language search of the PubMed and Ovid databases was conducted to identify publications from 1990 to 2016 reporting clinical outcomes of EMLP. Meta-analysis was performed using Statistical Analysis System 9.4. Results: A total of 1,205 patients were abstracted from 29 articles with a mean follow-up of 29.1 +/- 10.3 months. The overall rate of significant or complete symptom improvement was 86.5% (95% confidence interval [CI]: 84.2%-88.7%). The overall patency rate was 90.7% (95% CI: 89.1%-92.3%), with a revision rate of 12.6% (95% CI: 10.6%-14.3%). Compared to the early cohort, patients in the contemporary cohort underwent EMLP more often for tumors (P<.001), had higher rates of complete or significant symptom improvement (90.0% vs. 82.6 %, P<.001); and trended toward greater patency rates (92.1% vs. 88.6%, P=.052). Compared to the short-term follow-up cohort, the long-term cohort showed no differences in symptom improvement or patency, but the revision rate was higher (14.5% vs. 9.2%, P=.016). Conclusions: In the last decade, EMLP has been performed more frequently for tumors. Recent studies have demonstrated improved symptom outcomes and a trend toward improved patency rates. The revision rate increased significantly when follow-up exceeded 2 years.