ESD training: A challenging path to excellence.

Endoscopic submucosal dissection (ESD) has important advantages over endoscopic mucosal resection (EMR) for early gastrointestinal neoplasia treatment, but its difficult learning curve and associated risks have constrained its wider expansion. ESD training includes a comprehensive study of ESD basics, attending live cases and performing initial interventions in animal models, ideally under expert supervision. Mentoring methods in Japan and other Asian countries are reviewed, with a special concern in the conditions recommended for trainees to engage in an ESD program and achieve competence. Animal training is usually based on the well-known porcine model. Ex vivo models for esophageal, gastric and rectal ESD are cheap and easy to set up, whereas in vivo training requires special settings and veterinarian support. Nevertheless, it is advisable to gain experience in the live pig, with conditions that are similar to humans, before moving on to real patients. Particular attention is focused on colorectal ESD (CR-ESD), one of the most difficult locations for this technique. Since most of the potential lesions for ESD in Western countries are located in the colon or rectum, excellence in training is of paramount importance for successful outcomes in CR-ESD in the West.