Impact of robotic surgery proportion among minimally invasive gastrectomy on surgical complications.

[OBJECTIVE] The Safety of robotic gastrectomy (RG) compared to laparoscopic gastrectomy (LG) for gastric cancer remains uncertain on a national scale, with limited comparative studies across institutions. This study aims to compare the morbidity rates between RG and LG using data from a nationwide survey.

[METHODS] We utilized data from the Korean Gastric Cancer Association's 2019 nationwide survey. The proportion of robotic surgeries in minimally invasive surgery at each institution was classified using a cut-off value of 10%, and defined as high robotic proportion cohort and low robotic proportion cohort. We analyzed surgical outcomes between robotic and laparoscopic gastrectomy in each cohort using propensity score matching (PSM). To account for potential clustering effects within hospitals, we employed Generalized Estimating Equations with hospital as the clustering variable.

[RESULTS] This study included 776 patients who underwent RG and 7,804 patients who underwent LG for gastric cancer. In low robotic proportion cohort, RG had a longer operation time (P<0.001) but similar blood loss (P=0.792) compared to LG. In the high robotic proportion cohort, RG showed longer operation time (P<0.001), less blood loss (P<0.001), and shorter hospital stays (P<0.001) compared to LG. Additionally, RG in the high robotic proportion cohort had shorter operative time (P<0.001) and less blood loss (P=0.024) compared with that in the low robotic proportion cohort.

[CONCLUSIONS] RG demonstrated comparable perioperative outcomes to LG in a nationwide PSM analysis. However, RG offers limited benefits over LG at institutions with lower frequencies of RG use.