Experimental: Laparoscopic total gastrectomy

5 trocars were used. The gastrocolic ligament was divided along the border of the transverse colon. ligating the left gastroepiploic vessels to remove group 4sb.~The right gastroepiploic vein was divided and right gastroepiploic and inferior pyloric artery were transected at their origin from the gastroduodenal artery to dissect group 6.~The dissection was continued along the hepatoduodenal ligament to removed group 5 and group 12a and along the common hepatic artery to remove group 8a and along the celiac axis to remove group 9.~The left gastric vein was divided and then the left gastric artery was vascularized to remove group 7.~The dissection was continued upward along the splenic artery and its branches to remove group 11p,d and/or along the splenic hilum to remove group 10.~The dissection was then conducted the right and left of the esophago-gastric junction to remove group 1,2.~As a general rule, Roux en Y method was used for esophagoo-jejunal reconstruction for all cases

Active_comparator: Open total gastrectomy

An incision of 15\~20 cm length is made in the abdominal midline . Standard total gastrectomy and omentectomy will be performed with D2 lymph node dissection (around common hepatic artery, celiac artery, along splenic artery, proper hepatic artery, and/or the splenic hilum) . Roux-en Y esophagojejunal anastomosis is performed for reconstruction.