Study on Laparoscopic Spleen-Preserving No. 10 Lymph Node Dissection for Advanced Gastric Cancer

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）.

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）.

Eligibility Criteria:
Inclusion Criteria:

1. Age between 18 to 75 years old
2. Primary gastric adenocarcinoma (papillary, tubular, mucinous, signet ring cell, or poorly differentiated) confirmed pathologically by endoscopic biopsy
3. Locally advanced tumor in the upper third stomach（cT2-4a, N-/+, M0 at preoperative evaluation according to the AJCC(American Joint Committee on Cancer) Cancer Staging Manual Seventh Edition）
4. No distant metastasis, no direct invasion of pancreas, spleen or other organs nearby in the preoperative examinations
5. Performance status of 0 or 1 on ECOG (Eastern Cooperative Oncology Group) scale
6. ASA (American Society of Anesthesiology) class I to III
7. Written informed consent

Exclusion Criteria:

1. Pregnant and lactating women
2. Suffering from severe mental disorder
3. History of previous upper abdominal surgery (except for laparoscopic cholecystectomy)
4. History of previous gastric surgery (including ESD/EMR (Endoscopic Submucosal Dissection/Endoscopic Mucosal Resection )for gastric cancer)
5. Enlarged or bulky regional lymph node （diameter over 3cm）supported by preoperative imaging including enlarged or bulky No.10 lymph node
6. History of other malignant disease within the past 5 years
7. History of previous neoadjuvant chemotherapy or radiotherapy
8. History of unstable angina or myocardial infarction within the past 6 months
9. History of cerebrovascular accident within the past 6 months
10. History of continuous systematic administration of corticosteroids within 1 month
11. Requirement of simultaneous surgery for other disease
12. Emergency surgery due to complication (bleeding, obstruction or perforation) caused by gastric cancer
13. FEV1\<50% of the predicted values
14. Splenectomy must be performed due to the obvious tumor invasion in spleen or spleen blood vessels.