Laparoscopic Suprapancreatic Lymph Node Dissection Using a Systematic Mesogastric Excision Concept for Gastric Cancer

Background Gastrointestinal cancer surgery requires en bloc removal of the primary tumor and organ-specific mesentery 1 , 2 . However, this surgical concept for gastric cancer has not yet been applied because of the morphological complexity of the mesenteries of the stomach. Lymph node dissection in gastric cancer surgery can be roughly performed into three regions: lesser curvature, grater curvature, and suprapancreatic region. In this video, we introduced laparoscopic lymphadenectomy in the suprapancreatic region using a systematic mesogastric excision (SME), which has been reported as a concept to perform en bloc resection 3 . Methods This procedure was divided into three steps. First, mesenterization of the mesogastrium was performed by dissecting the embryological planes, and the mesogastrium was dissected from the retroperitoneal surface (Fig. 1 a). Second, soft tissue, including the lymph node, was separated from the pancreas and the splenic artery by tracing the inner dissectable layer (Fig. 1 b). Finally, the tumor-specific mesentery was transected according to the extent of the lymphadenectomy (Fig. 1 c). Fig. 1 Intraoperative findings during the stepwise procedure in dissecting the lymph node in the suprapancreatic region. The red broken line indicates the surgical outline. a The mesogastrium is dissected from the retroperitoneal tissue. b The mesogastrium is separated from the pancreas and splenic artery. c The mesogastric transection line is determined on the basis of the extent of the lymphadenectomy. Inf. phrenic a. inferior phrenic artery; PGA posterior gastric artery; Post. epiploic a. posterior epiploic artery; RV renal vein; SA splenic artery; SV splenic vein Results Between January 2017 and December 2017, six patients underwent laparoscopic distal gastrectomy with D2 lymphadenectomy using SME. The median time required to complete the suprapancreatic lymphadenectomy was 48 min. No patient underwent conversion to open surgery or experienced intraoperative complications. Conclusions We believe that this laparoscopic suprapancreatic lymphadenectomy using SME takes advantage of the surgical anatomy and achieves en bloc removal of the primary tumor and gastric mesentery. This series is a proof of concept that this procedure can be performed in a timely manner and is feasible.