Fig. 2

Endoscopic submucosal dissection (ESD). a Anal extent of resection. b Adoral extent of resection: 1-cm margin from the SC junction, taking into consideration the progression under the squamous epithelium. c Circumferential incision at the caudal end of the lesion. d Creation of the entrance of a submucosal tunnel at the cranial end of the lesion. e Tunnel creation by submucosal dissection. The upper side of the image is the mucosa and the lower side is the muscle. f Creation of three submucosal tunnels. g Complete circular ESD was performed. h En bloc resected cylindrical specimen