First pilot trial of colorectal ESD guided by a new magnetic anchor for ease of placement

Background In recent years, studies have demonstrated that magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD) is feasible and safe and may facilitate the treatment of all difficult lesions. However, the major problem with MAG-ESD is the inability to deliver the magnetic anchor to the gastrointestinal tract without withdrawal or reinsertion of the endoscope. Therefore, our team developed a magnetic anchor that could be easily inserted through the biopsy channel, facilitating ESD traction and evaluated its effectiveness and safety. Methods The study was conducted between October 2020 and June 2021 at The Second Affiliated Hospital of Harbin Medical University, China. One hundred and twelve patients with colorectal tumors treated with ESD were divided into two groups for historical control comparison. A channel-placed magnetic anchor (CPMAG) group and a control group consisting of patients who had conventional ESD without adjuvant traction. The rate of en bloc resection and resection with tumor-free lateral/basal margins (R0 resection), dissection speeds, procedure time, intraoperative bleeding and perforation complications, and postoperative follow-up were compared between the two groups, so as to evaluate the clinical effect and safety of the new magnetic anchor. Results The en bloc resection and R0 resection rate with CPMAG-ESD were slightly higher than with conventional ESD but this was not statistically significant. The median dissection speeds with CPMAG-ESD were higher than with conventional ESD, but the difference was not statistically significant. Intraoperative bleeding and postoperative complications with the CPMAG-ESD were less than with conventional ESD, but this was not statistically significant. The median operating time was shorter with CPMAG- ESD than with conventional ESD (24.5 min [range 15.8–66.5 min] vs 39 min [range 29–58 min], p = 0.024), and this difference was statistically significant. Conclusions The new magnetic anchor-guided ESD technique appears to be a feasible and safe method for treating early colorectal tumors with en bloc resection, with improvement of the submucosal visual field, and less adverse events.