Safety and short-term efficacy of gastrectomy after preoperative chemotherapy plus immunotherapy versus preoperative chemotherapy: A retrospective cohort study

Purpose: This study was conducted to compare the safety and short-term efficacy of gastrectomy after preoperative chemotherapy plus immunotherapy (PCIT) versus preoperative chemotherapy (PCT) in patients with advanced gastric cancer (AGC). Methods: We retrospectively reviewed the data of patients with AGC who received PCIT or PCT at Peking University Cancer Hospital and Institute Gastrointestinal Cancer Center I between January 2019 and June 2021. The clinical characteristics were recorded, and short-term oncological outcomes were compared. Independent t-tests, Mann-Whitney U tests, Chi-square tests, and Fisher’s exact tests were used to calculate differences. The correlation analyses were performed using Pearson correlation. All p values were two-sided, and a p-value <0.05 was considered as statistically significant. All the above statistical analyses were conducted by the SPSS version 24.0 software package (IBM Corp., Armonk, NY, USA). Results: A total of 162 AGC patients were included in this study, including 25 patients receiving PCIT and 137 patients receiving PCT. There were no significant differences in preoperative treatment-related adverse events (TRAEs) between the PCIT group and the PCT group (p=0.088). Compared with the PCT group, the PCIT group had comparable postoperative functional recovery, with no significant differences in terms of the first aerofluxus time (p=0.349), the first defecating time (p=0.800), the first time on liquid diets (p=0.233), and length of stay (p=0.278). No significant differences were observed in terms of postoperative complications (p=0.952), postoperative pain intensity at 24, 48, and 72 hours (p=0.375, p=0.601, and p=0.821, respectively), and postoperative supplementary analgesic between the two groups (p=0.881). In addition, the postoperative complication rates were 33.3% following the laparoscopic approaches and 31.2% following the open approaches in the PCIT group, with no significant difference (p=1.000). Conclusions: In patients with AGC, gastrectomy with D2 or D2+ lymphadenectomy after PCIT was comparable to PCT in terms of short-term oncological outcomes. The safety of LG was similar to that of OG in patients with AGC after PCIT.