ERBB2 and gastric cancer: In the DESTINY-Gastric01 primary cohort of patients with HER2+ gastric cancer centrally confirmed as immunohistochemistry (IHC) score 3+ or IHC 2+/in situ hybridization (ISH)+ using the most recent archival or fresh biopsy tumor tissues, T-DXd significantly improved ORR compared with physician choice of chemotherapy (TPC; ORR 51% (95% confidence interval (CI)3 42–61%) versus 14% (95% CI 6–26%)) and led to significantly improved overall survival (OS; median OS 12.5 months (95% CI 9.6–14.3 months) versus 8.4 months (95% CI 6.9–10.7 months))4.