• colorectum;
  • endoscopic submucosal dissection (ESD);
  • perforation;
  • thin endoscope assisted-ESD (TEA-ESD);
  • training

Endoscopic submucosal dissection (ESD) can successfully resect early stage gastrointestinal tumors, but colorectal ESDs are not widely performed, even by Japanese endoscopists, because of several negative factors. Besides being considerably more difficult in terms of technical demands, colorectal ESDs involve a longer procedure time and have a higher complication rate compared to gastric ESDs. In addition, most colorectal lesions are adenomas or intramucosal cancers that despite their large size that can be curatively treated by endoscopic mucosal resection including piecemeal resection.

There is, however, no doubt about ESD having a major therapeutic advantage in being able to achieve a higher en-bloc resection rate resulting in enhanced curability and more accurate histopathological assessment. Continued improvement in the technical skills of endoscopists, further refinement of such devices as electrical surgical knives and a special colonoscope as well as the development of more effective submucosal injection solutions and new traction systems are expected to facilitate easier, faster and safer colorectal ESD procedures in the relatively near future.