ENDOSCOPIC SUBMUCOSAL DISSECTION FOR ANORECTAL TUMOR CLOSE TO THE DENTATE LINE

Abstract

Lower rectal lesions close to the dentate line can be difficult to resect endoscopically because of the risk of bleeding from the rectal venous plexus, the sensory nerves in the squamous epithelium below the dentate line which cause pain during the procedure, the narrow lumen in proximity of the anal sphincter which makes it difficult to have a good visual field, and the presence of hemorrhoids. Special measures employed for endoscopic submucosal dissection (ESD) of lesions close to the dentate line are as follows: A transparent hood is attached to the tip of the endoscope. Lidocaine is locally injected into the submucosal squamous epithelial layer on the anal side of the lesion. The first mucosal incision is performed, and submucosal dissection is initiated on the anal side of the lesion. A shallow peripheral mucosal incision is made. Blood vessels are appropriately handled with hemostatic forceps. Using these measures, ESD for anorectal tumors close to the dentate line can be a safe and effective therapeutic procedure regardless of the presence of hemorrhoids.