Full-thickness endoscopic resection of gastrointestinal cancer: from animal lab to humans

Background: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are currently used for resection of early gastrointestinal (GI) tract cancer, limited to superficial layers of the gastric and colonic wall. These techniques are technically difficult, labor intensive and cannot be used when tumor cannot be lifted with submucosal injection and/or involves deeper layers of GI tract wall. Aim: To study technical feasibility and safety of full-thickness colonic resection in a live porcine model and the first clinical experience in humans. Methods: We performed endoscopic full-thickness resections of gastric and colonic wall in nine 50-kg domestic pigs. After resection the defects in GI tract wall were sutured with Overstitch® endoscopic suturing device Apollo Endosurgery Inc, Austin, TX). Three animals were sacrificed post procedure. Six animals were survived for 14 days and subsequently sacrificed for postmortem examination. Then endoscopic full-thickness resection of the colonic wall was performed in a patient with actively bleeding colon cancer, who was not a surgical candidate due to severe concomitant medical problems. Results: Large (3–5 cm) full-thickness endoscopic resections of gastric (3 animals) and colonic (4 animals) wall were easily achieved using hook knife, IT-knife and polypectomy snare (all made by Olympus, Tokyo, Japan). Suturing with the Overstitch® endoscopic suturing device was technically easy and achieved airtight closure of the GI tract in all animals. Postmortem examination reveal good full-thickness healing of the GI tract wall at the sites of resection. After gaining significant experience in endoscopic suturing we performed full-thickness endoscopic resection on a 64-year old man with actively bleeding colon cancer located at hepatic flexure. The patient required anticoagulation and was not able to tolerate even laparoscopic resection due to severe heart problems. The cancer was 2 × 4 cm and could not be lifted with submucosal injection of normal saline. After endoscopic resection, 4 × 6 cm full-thickness defect in colonic wall was completely closed with continuous suture line. The patient had no pain post procedure and was discharged home in 3 days. Follow-up endoscopy in 3 and 6 months revealed good healing of colonic wall without any residual cancer or strictures. Conclusion: This is the first reported purely endoscopic, full-thickness resection of GI tract cancer in humans. This procedure can be used even when EMR and ESD are not possible and can potentially become another valuable alternative to laparoscopy and open surgery.