Similar Operative Outcomes between the da Vinci Xi^® and da Vinci Si^® Systems in Robotic Gastrectomy for Gastric Cancer

Purpose: The robotic system for surgery was introduced to gastric cancer surgery in the early 2000s to overcome the shortcomings of laparoscopic surgery. The more recently introduced da Vinci $Xi^{(R)}$ system offers benefits allowing four-quadrant access, greater range of motion, and easier docking through an overhead boom rotation with laser targeting. We aimed to identify whether the $Xi^{(R)}$ system provides actual advantages over the $Si^{(R)}$ system in gastrectomy for gastric cancer by comparing the operative outcomes. Materials and Methods: We retrospectively reviewed all patients who underwent robotic gastrectomy as treatment for gastric cancer from March 2016 to March 2017. Patients' demographic data, perioperative information, and operative and pathological outcomes were collected and analyzed. Results: A total of 109 patients were included in the $Xi^{(R)}$ group and 179 in the $Si^{(R)}$ group. Demographic characteristics were similar in both groups. The mean operative time was 229.9 minutes in the $Xi^{(R)}$ group and 223.7 minutes in the $Si^{(R)}$ group. The mean estimated blood loss was 72.7 mL in the $Xi^{(R)}$ group and 62.1 mL in the $Si^{(R)}$ group. No patient in the $Xi^{(R)}$ group was converted to open or laparoscopy, while 3 patients in the $Si^{(R)}$ group were converted, 2 to open surgery and 1 to laparoscopy, this difference was not statistically significant. Bowel function was resumed 3 days after surgery, while soft diet was initiated 4 days after surgery. Conclusions: We found no difference in surgical outcomes after robotic gastrectomy for gastric cancer between the da Vinci $Xi^{(R)}$ and da Vinci $Si^{(R)}$ procedures.