Comparison of Surgical and Oncological Outcomes of Laparoscopic and Open Gastrectomy for Pathologically Serosa-Invasive (pT4a) Advanced Gastric Cancer-Retrospective Propensity Score-Matched Analysis.

Background: We aimed to clarify the operative feasibility and oncological efficacy of a laparoscopic gastrectomy (LG) for pT4a gastric cancer through comparison with open gastrectomy (OG). Materials and Methods: We compared surgical and oncological outcomes in 178 patients with pT4a gastric cancer who underwent LG or OG between 2002 and 2016; the background was adjusted using propensity score matching. Results: After score matching, 45 patients were included in each group. The LG group had a significantly longer operation time (277 minutes versus 175 minutes, P  < .001) and lower estimated blood loss (50 mL versus 280 mL, P  < .001). The total number of dissected lymph nodes did not differ between groups (46 versus 38, P  = .119); however, the number of dissected suprapancreatic lymph nodes was significantly higher in the LG group (11 versus 7.5, P  = .011). Postoperative morbidity rates did not differ between groups. Postoperative hospitalization was significantly shorter in the LG group (7 days versus 13 days, P  < .01), whereas overall survival, disease-free survival, and cancer recurrence rates and patterns were similar between groups. Conclusions: LG for pT4a gastric cancer has feasible and acceptable outcomes compared with OG.