ERBB2 and gastric cancer: Nivolumab combined with chemotherapy significantly improved the progression-free survival (PFS) and overall survival (OS) in the first-line treatment of HER2-negative gastric cancer patients (Janjigian et al., 2021), while in HER2-positive gastric cancer, pembrolizumab plus trastuzumab and chemotherapy recently showed a superior efficacy (Janjigian et al., 2020).