ERBB2 and breast cancer: In addition, Trastuzumab emtansine and Trastuzumab deruxtecan, both targeting HER2+ breast cancer, are associated with an increased risk of interstitial lung disease (ILD)/pneumonitis, which must be carefully managed with dose adjustment and supportive care recommendations to avoid fatal outcomes (Ma et al., 2018; Hackshaw et al., 2020).