Surgical invasiveness and lymphadenectomy in robotic and laparoscopic gastrectomy: A retrospective study with propensity score matching

Background
There is no consensus amongst the comparative studies analyzing the advantages of robotic surgeries over laparoscopic surgeries for gastric cancer. We compared robotic surgery and laparoscopic surgery in terms of minimal invasiveness and lymph node dissection.
Methods
We retrospectively reviewed the medical records of 215 consecutive patients with gastric cancer who underwent robotic or laparoscopic gastrectomy (RG or LG) with lymphadenectomy at our institution between January 2011 and December 2020. Exclusion criteria were residual gastric cancer, proximal gastrectomy, and D1 lymphadenectomy. Propensity score matching analysis was performed to control selection bias by age, sex, body mass index, operation method, lymphadenectomy, and pathological stage. We selected 34 matched pairs. Comparisons between groups were performed using Fisher’s exact test or the Mann-Whitney U-test. Short-term outcomes and site-specific lymph node dissection between the two groups were compared.
Results
The RG group had lower operative blood loss (11 vs. 100 mL, P=0.0005) and lower C-reactive protein levels on postoperative day 1 (5.1 vs. 7.0 mg/dL, P=0.0006) than the LG group. The number of lymph nodes retrieved was higher in the RG group (42 vs. 31, P=0.0150) than in the LG group. Moreover, when analyzing the specific sites dissected, we found that station groups of supra-pancreatic area (7, 8a, 9 and 11p) and lesser curvature area (1, 3a, 3b and 5) accounted for this difference (P=0.0073 and 0.0362, respectively).
Conclusions
RG demonstrated lesser intraoperative bleeding, lesser postoperative inflammatory response, and higher proportion of lymph node removal, especially in the supra-pancreatic area, than LG, suggesting a better surgical and oncological procedure.