ESD procedure

Marking was done around 2mm outside the margin of target lesion with needle knife or Dual knife (Force coagulation-1, 20 W). An initial cut was made with a tip-uncovered knife outside the marking after injecting a glycerol solution of epinephrine (1:100,000) and diluted indigo carmine into the submucosal layer. Injection volume varied according to lesion size, and injections were repeated during the procedure as needed. Mucosal circumferential cutting was performed with IT knife (pulse slow cutting 25 W). Submucosal dissection was performed with IT knife or tip-uncovered type knife (force coagulation-2, 40 W). Intra-operation bleeding was managed with coagrasper (soft coagulation, 70 W).