Robotic Versus Laparoscopic Distal Gastrectomy With D2 Lymphadenectomy for Locally Advanced Gastric Cancer: a Multicenter Randomized Controlled Trial

Since the first case of laparoscopy-assisted distal gastrectomy was reported 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 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). According to the results of large-scaled retrospective studies and ongoing randomized controlled trials (RCTs), LG treating AGC can gain better short-term outcomes and comparable long-term oncologic results.

To minimize the limitations of laparoscopic surgery, robot systems have been introduced to treat GC providing technical advantages. Though the feasibility and safety of robotic gastrectomy (RG) have been well accepted, the benefits of RG remain controversial. A recent meta-analysis including eleven studies of 3503 patients demonstrated that RG indicated potentially favorable outcomes in terms of blood loss compared with LG. Furthermore, it has been confirmed that robotic system could provide an advantage over LG in the dissection of the N2 area lymph nodes, especially around the splenic artery area. Our previous study demonstrated that the RG had less intraoperative blood loss and more lymph nodes dissection compared with the laparoscopic procedure. However, the only prospective study reported that RG is not superior to LG in terms of perioperative surgical outcomes. Nevertheless, the following subgroup analysis found that patients with GC undergoing D2 lymph node dissection can benefit from less blood loss when a robotic surgery system is used. Take together, RG with D2 nodal dissection may be superior laparoscopic surgery in terms of blood loss and retrieved lymph nodes. However, lack of high-level evidence-based medical researches, we can't drew a conclusion that patients with AGC may benefit from RG with D2 nodal dissection.

With regard to a new surgical approach, oncologic safety has attracted more attention. Although some retrospective studies have demonstrated that RG with lymphadenectomy for GC had non-inferior oncologic outcome relative to LG, there is no prospective RCT to evaluate the long-term outcomes of RG. Therefore, the Chinese Robotic Gastrointestinal Surgery Study (CRASS) Group launched a multicenter prospective RCT to verify the short-term and long-term outcomes of RG in AGC. The primary objective of this study is to assess whether robot-assisted distal gastrectomy is comparable to laparoscopic approach in terms of long-term oncologic outcomes without compromising relapse-free survival. The secondary research objectives are to compare robotic and laparoscopic approach in terms of morbidity, mortality, quality of life, cost-effectiveness, and overall survival.