Pocket-creation method improves efficacy of colorectal endoscopic submucosal dissection: a system review and meta-analysis.

The pocket-creation method (PCM) is a new strategy for endoscopic submucosal dissection (ESD). The aim of this system review is to evaluate the clinical efficacy and safety of PCM-ESD compared to conventional ESD (C-ESD) for colorectal neoplasm lesions. We performed literature search using MEDLINE, EMBASE and CENTRAL database from inception to 15 February 2020. Studies provided comparison between PCM-ESD and C-ESD for colorectal neoplasm lesions were included. En bloc resection rate, R0 resection rate, occurrence rate of adverse events and operation speed/time were extracted from included studies. Pooled risk difference with 95% confidence intervals (CIs) was calculated in meta-analysis. Three cohort studies and one randomized control trial (RCT) were included, which contained 432 colorectal lesions removed by PCM-ESD and 959 lesions resected by C-ESD. PCM-ESD achieved significantly higher en bloc/R0 resection rate than C-ESD in cohort studies with pooled risk differences of 0.05 (CI, 0.03-0.07, I2 = 34%) and 0.14 (CI, 0.04-0.24, I2 = 83%). However, comparison of en bloc/R0 resection rate between two surgery strategies could not be estimated in RCT. Pooled results in cohort studies and data from RCT revealed comparable occurrence rate of adverse events between PCM-ESD and C-ESD. Measurements and outcomes of operation time/speed varied between the included studies and no consistent conclusion could be achieved in this aspect. The results indicate that PCM-ESD is an effective and well-tolerated treatment for colorectal neoplasm lesions and may be a superior treatment to C-ESD in en bloc/R0 resection rate.