Reduced intestinal‐to‐diffuse conversion and immunosuppressive responses underlie superiority of neoadjuvant immunochemotherapy in gastric adenocarcinoma

Abstract Neoadjuvant immunochemotherapy (NAIC) achieves superior clinical benefits over neoadjuvant chemotherapy (NAC) in multiple types of human cancers, including gastric adenocarcinoma (GAC). However, it is poorly understood how the malignant epithelial cells and tumor immune microenvironment (TIME) might respond distinctly to NAIC and NAC that underlies therapeutic efficacy. Here treatment‐naive and paired tumor tissues from multiple centers were subjected to pathological, immunological, and transcriptomic analysis. NAIC demonstrated significantly increased rate of pathological complete response compared to NAC (pCR: 25% vs. 4%, p