ERBB2 and non-small cell lung carcinoma: Specifically, clinical responders to T-DXd (n = 36) included 28 patients with NSCLC with on-label ERBB2mut, 2 patients with NSCLC with off-label ERBB2mut (TMD V659E and an Ex20Ins (A775_G776insYLMA), both without HER2 IHC assessment and negative for ERBB2 co-amplification by NGS), and 6 non-NSCLC patients (N = 2 with HER2 IHC 3+ and N = 4 that were HER2 IHC-negative/not assessed).