GATSBY study aims to evaluate the efficacy of trastuzumab emtansine (TDM-1) in patients previously treated for HER2-positive advanced gastric cancer.The ORR was 20.6% in TDM-1 group and 19.6% in taxane group.The median PFS was 2.7 months in TDM-1 group and 2.9 months in taxane group (56).RAINBOW study showed that the ORR was 28% in ramucirumab plus paclitaxel cohort and 16% in placebo plus paclitaxel cohort.The PFS was 4.4 months vs 2.86 months,respectively (57). Here, ERBB2 is linked to gastric cancer.