Abstract
BACKGROUND: This retrospective study focused on patients with advanced gastric cancer (AGC) for whom traditional chemotherapy has limited efficacy and responses to immune checkpoint inhibitors (ICI) vary. It explored biomarkers for predicting immunotherapy response, with a particular focus on the modified Gustave Roussy immune score (mGRIm-s). METHODS: The retrospective study enrolled 268 patients with stage IV gastric cancer who initiated ICI treatment at the PLA General Hospital between December 2014 and May 2021. Patients were stratified into low-risk and high-risk groups based on three risk factors: low albumin levels, high lactate dehydrogenase levels, and an elevated neutrophil-lymphocyte ratio. RESULTS: The results showed that patients in the low mGRIm-s group had significantly longer progression-free survival (PFS) and overall survival (OS) compared to those in the high mGRIm-s group. Cox regression analysis identified high mGRIm-s as a significant risk factor for disease progression and mortality. Additionally, patients in the low mGRIm-s group demonstrated higher disease control rates in short-term efficacy assessments. CONCLUSION: This retrospective study provides new insights into the relationship between mGRIm-s and survival outcomes in AGC patients undergoing anti-PD-1 immunotherapy.