In the highly influential ToGA study [7], it was shown that compared with chemotherapy alone, the application of targeted therapy with trastuzumab in combination with chemotherapy could prolong the progression-free survival (PFS) of patients with HER2-positive GC from 5.5 to 6.7 months, while simultaneously improving the objective response rate (ORR) from 35 to 47%. Here, ERBB2 is linked to gastric cancer.