Current Trends on the Status of Transanal Endoscopic Microsurgery

Purpose of Review Transanal endoscopic surgery (TES) is the standard of care for the local excision of large rectal adenomas and selected rectal cancers: an "en bloc" full-thickness local excision is performed, with limited risk of specimen fragmentation and positive resection margins, and subsequent significantly lower risk of recurrence and better survival than after conventional transanal excision with retractors. We perform a literature review aiming at assessing the current trends on the status of TES. Recent Findings Patients undergoing TES report significantly lower rates of postoperative complications and better functional outcomes than patients who receive abdominal rectal resection with total mesorectal excision, with no adverse impact on long-term survival. To date, there are two different rigid platforms that are available to perform a TES procedure: the transanal endoscopic microsurgery (TEM) platform that was conceived by Buess in the early 1980s and the TEO (transanal endoscopic operation) platform. More recently, flexible platforms have been proposed as alternative to the rigid ones. Summary Based on the current evidence, TEM and TEO represent the current standard of treatment for large rectal adenomas and selected rectal cancers. Large comparative studies are needed to assess the benefits of flexible platforms, considering that the wide adoption of flexible platforms might impair the quality of the local excision, mainly if performed in low-volume centers.