Aggressive endoscopic mucosal resection in the upper GI tract - Hook knife EMR method.

We have developed a new EMR method, the 'Hook knife' method, for the en-bloc resection of larger lesions. First, we placed marks around the lesion with a coagulation tip. Next, 10% glycerol diluted epinephrine solution was injected into the submucosal layer to separate the mucosa from the muscular layer proper. Then, we cut the mucosa around the lesion with a needle knife. Finally, we cut the submucosal fibers and vessels using a hook-type knife and resected the lesions. A large en-bloc resection, ≥70 mm in size, was possible with this new EMR method. Because of this, the histological examination for both the range of lateral spreading and the depth of invasion can be made more precisely. Aggressive endoscopic mucosal resection is established by this new EMR method.