Gastrointestinal Subepithelial Lesions: Evolution in Management and Endoscopic Resection Techniques

Subepithelial lesions (SELs) are tumors originating from the gastrointestinal (GI) tract wall (muscularis mucosa, submucosa, or muscularis propria) and are covered by overlying mucosa. They are typically incidental findings during routine endoscopy. This article reviews the latest advancements in endoscopic techniques and devices used to resect subepithelial lesions.

Endoscopic Ultrasound (EUS) should be employed to characterize SELs, with fine needle core biopsy (FNB) utilized with EUS for histopathologic tissue acquisition. EUS can be used as "endoscopic mapping" to mitigate serious complications prior to endoscopic resection. Techniques such as Submucosal Tunnelling Endoscopic Resection (STER), Device-Assisted Endoscopic Full Thickness Resection, and Freehand Full Thickness Resection are available for the complete resection of SELs. The choice of technique depends on the characteristics of the lesion and the level of expertise of the endoscopist. Multiple endoscopic resection techniques for SELs have been developed, each utilizing different tools and devices. A significant shift has occurred from traditional laparoscopic surgical resection to minimally invasive, organ-sparing endoscopic resection. Advancements in "third space" endoscopy and the innovation of novel devices continue to offer less invasive resection techniques for lesions arising from the GI tract wall.