Supplementation of endoscopic submucosal dissection with sentinel node biopsy performed by natural orifice transluminal endoscopic surgery (NOTES) (with video)

BackgroundEndoscopic submucosal dissection (ESD) is proving to be effective for the resection of selected early gastric and colon cancers. Its application and appropriateness could be extended if a means of determining lymphatic dissemination without recourse to a conventional operation could be provided.ObjectiveTo demonstrate the feasibility of companion sentinel node biopsy (SNB) by natural orifice transluminal endoscopic surgery (NOTES) concurrent with intraluminal ESD in both the sigmoid colon and stomach.DesignAcute porcine model.InterventionArbitrarily selected mucosal foci were targeted for combined NOTES-SNB and ESD in the sigmoid and stomach of 2 separate anesthetized animals. NOTES peritoneal access was obtained either transgastrically or transvaginally. A second intraluminal endoscope was passed either orally or rectally, as appropriate, to perform submucosal injection for lymphatic mapping under direct vision of the NOTES endoscope. This endoscope then identified the first-order draining (sentinel) nodes and allowed their excisional biopsy. The sigmoid was retracted by magnetic assistance as required, while torque of an intraluminal gastroscope manipulated the stomach. After retrieval of the nodes, 1-cm and 1.5-cm specimens were resected from the sigmoid and stomach, respectively, by conventional ESD. At procedure end, necropsy was performed.ResultsAll sentinel nodes were identified, underwent biopsy, and were retrieved intact. ESD was subsequently readily performed without complication. SNB completeness and ESD quality were confirmed postprocedure.LimitationsExperimental model with limited sample size.ConclusionsAlthough not yet appropriate for human use, this proposal merits serious consideration as a potential means of augmenting the effectiveness and appropriateness of ESD techniques for GI neoplasia.