In the most recent data for HER2-positive breast cancer from the DESTINY-Breast03 trial, the incidence of any-grade drug-related ILD/pneumonitis with T-DXd was lower at 10.5% (27 of 257) compared with prior DESTINY trials, with no grade 4 or fatal events observed (Table 1).16 The gene discussed is ERBB2; the disease is breast carcinoma.