Endoscopic submucosal dissection using flexknife

Although the standard treatment for early-stage gastrointestinal tumors is still surgical resection, endoscopic resection has been accepted for some of these lesions, especially in Japan. However, the indication was limited until recently to achieve en bloc resection and prevent local recurrence. To overcome the disadvantage of endoscopic resection with conventional endoscopic mucosal resection (EMR), several investigators, including us, have developed a new endoscopic resection technique: endoscopic submucosal dissection (ESD). ESD is a remarkable technique that enables to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. Nowadays, several knives are available for ESD, such as the needle knife, insulation-tipped (IT) knife, Hookknife, triangle-tipped (TT) knife, and Flexknife. Each of them has some merits and demerits, and the ways to use the knives are different. We summarize here how to use the Flexknife, which we made ourselves in cooperation with the Olympus Company, and how we use the technique in our hospital.