Indication and results of endoscopic submucosal dissection (ESD) for right located lateral spreading tumors (LST)

Endoscopic submucosal dissection (ESD) is a technique developed to overcome the limitation connected with the conventional endoscopic resection techniques and it is used for en bloc resection of larger mucosal tumors or slightly invasive tumors in gastrointestinal tract, representing a less invasive alternative to surgery for these lesions. In colorectum, ESD is performed on lesions with high suspicion of limited submucosal invasion and low risk of lymph node metastasis, and especially on lateral spreading tumors (LST), even if these lesions are not always removable by endoscopic resection and require combined endoscopic and laparoscopic surgery (CELS), particularly on right-side colon, which is more difficult to approach than left-side colon, facilitating the resection of the lesion through external manipulation of the bowel wall with laparoscopic instruments. Colorectal ESD is now considered the standard therapy of several superficial gastrointestinal lesions in Asian countries, presenting similar efficacy and less invasivity compared with surgery method and could become the reference treatment even in Western countries, but the inexperience of endoscopists and the risk of complications limit its practice. Although colorectal ESD is associated with a high risk of procedure-related adverse advents, like perforation and bleeding, this endoscopic technique has progressively become more safe and effective and complications are gradually improved with experience. The aim of this review is to describe the indications and the technique of colorectal ESD, especially performed on right-sided tumors, and to show how its effectiveness and safety has improved over the years.