The short-term efficacy of neoadjuvant SOX versus SOX plus immune checkpoint inhibitor following laparoscopic gastrectomy for locally advanced gastric cancer: a multicenter retrospective cohort study in China.

Background: This study aims to evaluate the short-term efficacy for locally advanced gastric cancer (LAGC) who accepted laparoscopic gastrectomy (LG) after neoadjuvant SOX versus SOX plus immune checkpoint inhibitors (ICIs).

Methods: LAGC patients who accepted LG after neoadjuvant SOX (SOX-LG, n = 169) and SOX plus ICIs (SOX + ICIs-LG, n = 140) in three medical centers between Jan 2020 and Mar 2024 were analyzed. We compared the tumor regression, treatment-related adverse events (TRAEs), perioperative safety between two groups, and explored the risk factors of postoperative complications (POCs) for LG after neoadjuvant therapy.

Results: The baseline characteristics were comparable between two groups (P > 0.05). SOX + ICIs-LG group acquired a higher proportion of objective response (63.6% vs. 46.7%, P = 0.003), major pathological response (43.6% vs. 31.4%, P = 0.001), and pathological complete response (17.9% vs. 9.5%, P = 0.030). There were no significant differences in the TRAEs rates, operation time, R0 resection, retrieved lymph nodes, postoperative first flatus, and hospitalized days, overall and severe POCs between two groups (P > 0.05). Patients in the SOX-ICIs-LG group had lower estimated blood loss (EBL) compared with SOX-LG (P = 0.001). Multivariate analysis showed that more EBL (P = 0.003) and prognostic nutritional index (PNI) < 40 (P = 0.005) were independent risk factors of POCs for LG after neoadjuvant therapy.

Conclusion: Neoadjuvant SOX plus ICIs brings better tumor regression and similar TRAEs compared with SOX alone for LAGC. SOX + ICIs-LG is safe and feasible to conduct with less EBL. Surgeons should focus on the perioperative management to control POCs for patients with PNI < 40 and more EBL.