Laparoscopic endoscopic cooperative surgery for early gastric cancer

The laparoscopic and endoscopic cooperative surgery (LECS) has been developed as a surgical procedure for submucosal tumor (SMT). The original LECS is not applicable for lesions with tumor exposed on the mucosal surface due to oncological safety. We describe surgical procedures of closed LECS for early gastric cancer cases, which don’t require opening of the stomach wall. We routinely combine partial resection (closed LECS) of early gastric cancer with sentinel lymphatic basin (LB) dissection. The stomach are laparoscopically conducted and a local injection of 0.5 mL indocyanine green (ICG) 0.5% (5 mg/mL) is endoscopically performed. Under the laparoscopic view of ICG fluorescence, the LB is dissected. Following removal of the whole sentinel node (SN), the LB is sent for the intraoperative pathology diagnosis. The closed LECS is started when all examinations confirm negative SN. The procedure corresponds to the regular LECS; a mucosal incision is made to connect the dot marking. Marking is made endoscopically during laparoscopy using pyocyanine along the dissection line of the circumferential incision on the submucosal layer. A sponge material spacer that is adjusted to the size of the marking line is prepared, which is applied to the serosal surface of the tumor, and serosal muscular layer suture is evenly added until the sponge is completely buried. The oral endoscopic operation is resumed, and incision of the muscular layer/serosa of the bulging tumor is made. The resected specimen is collected orally with an endoscopic retrieval device. After carefully confirming the operation field both endoscopically and laparoscopically, the operation is ended. The combination of the LECS and the SNNS techniques, while applicable cases are limited, is expected to be established as the effective surgical procedure of partial gastrectomy for early gastric cancer. In the future, we will develop the procedure carefully and proactively.