Long-term Oncologic Outcomes of Robotic Versus Laparoscopic Total Gastrectomy for Advanced Gastric Cancer

Long-term Oncologic Outcomes of Robotic Versus Laparoscopic Total Gastrectomy for Advanced Gastric Cancer: A Propensity Score Matching Study

This study is a retrospective, single-center, controlled and observation trial comparing robotic total gastrectomy with D2 lymph nodal dissection for locally advanced gastric cancer patients with laparoscopic procedure.

Since Kitano firstly reported laparoscopy-assisted distal gastrectomy in 1994, the number of patients undergoing the laparoscopic procedure has gradually increased. The latest Japanese gastric cancer treatment guideline recommends laparoscopic gastrectomy (LG) as an optional treatment for cStage（clinical stage） Ⅰ gastric cancer (GC).

Based on the experience of early GC, most experienced surgeons have applied the laparoscopic procedure in patients with locally advanced gastric cancer (AGC) especially in east world like China, Japan and Korea. Though applying laparoscopic total gastrectomy (LTG) is much more difficulty than that of distal gastrectomy (DG), there are a mount of centers reported their experiences of this procedure. A meta-analysis including seventeen studies of 2313 patients (955 in LTG and 1358 in open total gastrectomy) demonstrated that LTG can have less blood loss, fewer analgesic uses, earlier passage of flatus, quicker resumption of oral intake, earlier hospital discharge, and reduced postoperative morbidity. However, the number of harvested lymph nodes, proximal resection margin, hospital mortality, 5-year OS(overall survival) and DFS(disease-free survival) were similar in both groups. According to the existing reports, LTG is technically safety and feasibility.

To overcome the limitations of laparoscopic surgery, robot systems have been introduced to treat GC providing technical advantages since Hashizume firstly reported. Yoon and Son respectively compared robot total gastrectomy (RTG) with LTG, they drew a common conclusion that the number of dissected lymph nodes and postoperative complications were similar in both groups. But Son found that the mean numbers of retrieved lymph nodes along the splenic artery from RTG was higher than LTG (2.3 vs. 1.0, p = 0.013), as was also the case at the splenic hilum and artery (3.6 vs.1.9, p = 0.014). Regretfully, most of their reported cases were early gastric cancer (EGC). Other literatures reported AGC patients under RTG or LTG together with distal gastrectomy (DG), the investigators haven't found any literature compare RTG with LTG alone for AGC retrospectively.

Since most literatures are EGC patients and retrospectively researches, the investigators can't insist that patients with AGC may benefit under RTG. Therefore, the investigators launch this retrospective, single-center, controlled observation trial comparing RTG for locally advanced gastric cancer patients with LTG. In the process of research, it will be divided into two groups according to the willing of patients or their legal representatives who choose one of the two procedures(RTG or LTG) to cure GC.

Inclusion Criteria:

• 1.Pathologically proven gastric adenocarcinoma; 2.Age: older than 18 years old, younger than 80 years old; 3.Tumor located in the upper third of the stomach or esophagogastric junction or other location, and is possible to be curatively resected by total gastrectomy; 4.Preoperative stage of cT2-4aN0-3M0 according to American Joint Committee on Cancer/Union for International Cancer Control 8th edition; 5.American Society of Anesthesiology (ASA) score of class I to III; 6.Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1; 7.Patients who freely give informed consent to participate in the clinical study;

Exclusion Criteria:

• 1.Early gastric cancer; 2.Age: younger than 18 years old, older than 80 years old; 3.Total gastrectomy with D2 lymphadenectomy was not required; 4.Enlarged or bulky regional lymph node diameter larger than 3 cm based on preoperative imaging; 5.Emergency surgery for gastric cancer-related complications (bleeding or complete obstruction or perforation); 6.Previous upper abdominal surgery (except laparoscopic cholecystectomy); 7.Previous neoadjuvant chemotherapy or radiotherapy for gastric cancer; 8.Unstable angina or myocardial infarction within the past 6 months; 9.Cerebrovascular accident within the past 6 months; 10.American Society of Anesthesiology (ASA) score of class more than III; 11.Severe respiratory disease (FEV1< 50%); 12.Continuous systemic steroid therapy within 1 month before the study; 13.Pregnant or breast-feeding women;