Analysis of the treatment efficacy and prognostic factors of PD-1/PD-L1 inhibitors for advanced gastric or gastroesophageal junction cancer: a multicenter, retrospective clinical study.

Introduction: Immune checkpoint inhibitors (ICIs) have transformed advanced gastric cancer treatment, yet patient responses vary, highlighting the need for effective biomarkers. Common markers, such as programmed cell death ligand-1 (PD-L1), microsatellite instability/mismatch repair (MSI/MMR), tumor mutational burden, tumor-infiltrating lymphocytes, and Epstein-Barr virus, face sampling challenges and high costs. This study seeks practical, minimally invasive biomarkers to enhance patient selection and improve outcomes.

Joint analysis identified FAP as a prognostic and diagnostic biomarker correlated immune infiltration in gastric cancer.

Gastric cancer is one of the most malignant types of cancer in the digestive system because of its high incidence and mortality. There is a notable association between gastric cancer progression and the level and sort of immune cells infiltrating the tumor microenvironment. First, 41 up-regulated differentially expressed genes (DEGs) and 91 down-regulated DEGs were identified from the Gene Expression Omnibus (GEO) database.