Although DTICs were associated with ICI efficacy [52], it has not been widely used in clinical practice due to the lack of standard evaluation method and sufficient tumor samples after the multiple recommended tissue-based assessments, including protein expression of HER2, MMR, and PD-L1 by IHC, and Epstein-Barr virus-encoded small RNA by in situ hybridization in gastric cancer. Here, ERBB2 is linked to gastric cancer.