Safety and efficacy of minimally invasive gastrectomy for older patients with gastric cancer after neoadjuvant chemotherapy and immunotherapy: a propensity score-matched analysis

Background The effect of neoadjuvant immunotherapy on minimally invasive gastrectomy (MIG) in older patients with gastric cancer remains controversial. This study aimed to evaluate the safety, and efficacy of MIG for older patients who underwent neoadjuvant chemotherapy and immunotherapy (NICT). Methods The clinical data of 726 older patients aged over 65 years who underwent upfront MIG or MIG after NICT in the Department of General Surgery, Chinese PLA General Hospital First Medical Center between Jan 2020 and Nov 2023 were retrospectively analyzed. Propensity score-matched (PSM) analysis at a ratio of 1:2 was performed to reduce bias from confounding patient-related variables, short- and long-term outcomes were compared between the two groups. Results The baseline characteristics were comparable between 61 patients in the NICT-MIG group and 114 patients in the MIG group after PSM (P > 0.05). The major pathological response (MPR) rate and pathological complete response (pCR) rate were 44.2% and 21.3%, respectively, in the NICT-MIG group. Patients in the NICT-MIG group had longer operation times (P = 0.005) and postoperative days (P = 0.030) than those in the MIG group. No significant differences were found in intraoperative bleeding, number of retrieved lymph nodes, first flatus day, R0 resection rate, overall postoperative complication (POC) morbidity, severe POC morbidity, 2-year overall, and recurrence-free survival between the MIG and NICT-MIG groups (P > 0.05). Multivariate logistic analysis revealed that an estimated blood loss > 200 mL (P = 0.010) and a lymphocyte-to-monocyte ratio (LMR) <= 3.25 (P = 0.006) were independent risk factors for POCs after MIG in older patients. Conclusion The safety, and efficacy of NICT-MIG were comparable to those of upfront MIG in older patients with GC. Patients with an estimated blood loss > 200 mL or an LMR <= 3.25 should be carefully evaluated for an increased risk of POCs in older patients who undergo MIG. Trial registration: Chinese Clinical Trial Registry (Registration Number: ChiCTR2400086827).