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

Background: The safety and short-term outcomes of gastrectomy after preoperative chemotherapy plus immunotherapy (PCIT) versus preoperative chemotherapy (PCT) in patients with advanced gastric cancer (AGC) remain unclear. This study was conducted to compare the safety and short-term efficacy of PCIT with those of PCT in patients with 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 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 who received PCIT and 137 patients who received 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 time to first aerofluxus (p = 0.349), time to first defecation (p = 0.800), time to liquid diet (p = 0.233), or 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, or 72 h (p = 0.375, p = 0.601, and p = 0.821, respectively), or postoperative supplementary analgesic use between the two groups (p = 0.881). In addition, the postoperative complication rate was 33.3% following laparoscopic approaches and 31.2% following open approaches in the PCIT group, with no significant difference (p = 1.000). Conclusion: In patients with AGC, gastrectomy with D2 or D2 + lymphadenectomy after PCIT had comparable short-term oncological outcomes to PCT.