Recently, the U.S. Food and Drug Administration (FDA) granted accelerated approval for the use of pembrolizumab in combination with first-line trastuzumab and chemotherapy for the treatment of patients with HER2-positive metastatic GC [15], based on the interim data from the ongoing KEYNOTE-811 study (NCT03615326) [16]. This evidence concerns the gene ERBB2 and gastric cancer.