Abstract
BACKGROUND: Immunotherapy has brought clinical benefits for patients with advanced or late-stage gastric cancer. This real-world study aimed to evaluate the efficacy and safety of neoadjuvant immunochemotherapy in patients with locally advanced gastric cancer (LAGC). METHODS: Patients with LAGC (cT2-4bN1-3M0) were enrolled in this retrospective study. Patients received either neoadjuvant immunochemotherapy or chemotherapy alone before surgery. The primary endpoint was the pathological complete response (pCR) rate. RESULTS: A total of 111 patients were included in this study, with 49 received neoadjuvant PD-1 inhibitors combined with chemotherapy (Group A) and 62 received chemotherapy alone (Group B). pCR rate of Group A was significantly higher than that of Group B (22.4% vs. 4.8%, P = 0.011). Compared with the clinical TNM stage before neoadjuvant therapy, 32 (65.3%) patients in Group A had T downstaging, 27 (55.1%) had N downstaging, and 42 (85.7%) had overall TNM downstaging. There was no significant difference in 1-year OS rate (100% vs. 93.5%; P = 0.195) and 1-year DFS rate (81.6% vs. 75.8%; P = 0.144) between the two groups. 11.7% patients in Group A and 9.8% patients in Group B experienced grade ≥ 3 adverse TRAEs, myelosuppression, elevated ALT/AST, nausea, and decreased appetite. However, there was no significant difference between the two groups (P = 0.240). CONCLUSIONS: Here, neoadjuvant immunochemotherapy suggested a potential clinical benefit of the pCR rate, T downstaging, and a favorable safety profile for LAGC. However, further multicenter, large-scale randomized clinical trials are urgently needed to confirm the long-term survival benefit.