Clinical outcomes of endoscopic submucosal tunnel dissection compared with conventional endoscopic submucosal dissection for superficial esophageal cancer: a systematic review and meta-analysis

Background: Endoscopic submucosal dissection (ESD) is the standard treatment for superficial esophageal cancer. However, it has limitations in case of large superficial esophageal squamous cell neoplasms (SESCNs), in which submucosal injection cannot attain satisfactory lifting effects. Thus, endoscopic submucosal tunnel dissection (ESTD) was introduced as a new treatment for SESCNs presenting satisfying results. Many studies have tried to verify the efficacy of ESTD, yet no meta-analysis has been published until now. Methods: We searched the databases of PubMed, Cochrane Library, Web of Science, SinoMed, Wanfang, and CNKI dating up to February 1, 2019. Studies comparing the clinical outcomes of ESTD and ESD for superficial esophageal cancers were enrolled. The Newcastle-Ottawa Quality Assessment Scale was used to evaluate the quality of these studies. Eight articles were included that involved a total of 625 superficial esophageal cancer patients. Results: Our analysis revealed that ESTD is superior to ESD as it has higher en bloc resection rate, shorter operation time, and lower recurrence rate 1 year after operation. The R0 resection rate and postoperative adverse event rate of ESTD group is comparable with ESD group. Conclusions: Our study implicates that ESTD is a potentially superior treatment to ESD for superficial esophageal cancer.