Radical resection is still the primary method of treating advanced gastric cancer.According to the Japanese treatment guidelines for gastric cancer, D2 lymphadenectomy, including No. 10 lymph node dissection, should be adopted for upper third gastric carcinoma.The incidence of No. 10 lymph node metastasis is high in advanced proximal gastric cancer, reported to range from 9.8%-20.9%, and the presence of No. 10 lymph node metastasis is closely related to survival. Therefore, in East Asia, D2 lymph node dissection of potentially curable locally advanced upper third gastric cancer including No. 10 lymph node is the standard surgical treatment.~In the early, splenectomy was performed to remove No. 10 lymph node. With the improvement of medical knowledge and surgical technique, spleen-preserving No. 10 lymph node dissection has been recognized by more and more surgeons. However, due to the special and complex anatomy of the spleen, spleen-preserving No. 10 lymph node dissection is difficult, even in open surgery; consequently, the surgery cannot be performed in many centers.~Laparoscopic surgery has distinct minimally invasive advantages, such as small incisions, less blood loss, less postoperative pain, mild postoperative inflammatory reactions, a quick recovery of gastrointestinal function, shorter hospital stays and obvious cosmetic effects. Since Kitano et al. first reported laparoscopic gastrectomy for gastric cancer in 1994, laparoscopic techniques have developed rapidly. The techniques are becoming increasingly mature, making it possible to perform laparoscopic spleen-preserving No. 10 lymph node dissection. Our center first proposed Huang's three-step maneuver, a new operative method suitable for laparoscopic spleen-preserving No. 10 lymph node dissection. This method simplifies the procedure of laparoscopic spleen-preserving No. 10 lymph node dissection and facilitates its popularization and promotion.~However, it remains a controversial international issue if it is safe and feasible to routinely conduct laparoscopic spleen-preserving No. 10 lymph node dissection for advanced upper third gastric cancer.A number of retrospective studies have successively confirmed the safety, feasibility and oncological efficacy of laparoscopic spleen-preserving No. 10 lymph node dissection.But there is no multicenter prospective studies to identify the results.~Therefore, The study is through a prospective, multicenter, open, single-arm, non-inferiority study,to explore the safety and feasibility of the laparoscopic spleen-preserving No. 10 lymph node dissection for patients with locally advanced upper third gastric adenocarcinoma（cT2-4a, N-/+, M0）.
The purpose of this study is to explore the safety and feasibility of the Laparoscopic Spleen-Preserving No. 10 Lymph Node Dissection for patients with locally advanced upper third gastric adenocarcinoma（cT2-4a, N-/+, M0）.