The surgery case is a 54-year-old female with gastric cancer in the proximal posterior gastric cancer invading into the splenic hilum. Patient received staging laparoscopy and neoadjuvant chemotherapy. Due to the special location of the disease, total gastrectomy with the lesser sac and spleen en bloc resection with D2 lymph node dissection was performed. This video clip demonstrated the essential anatomy and the concept of lesser sac resection. Authors introduced the concept anatomic membrane dissection. The potential advantages of anatomic membranes dissection including less blood loss and better lymph node dissection were demonstrated. CT scan with 3D reconstruction, medical illustration and animation in combining with live video were used in this video clip.