In a study involving 18 patients with HER2-mutated advanced lung adenocarcinomas, a response rate of 44% and a median progression-free survival (PFS) of 5 months was observed for T-DM1.21 Furthermore, the DESTINY-Lung 01 trial enrolled 91 metastatic HER2-mutated non-small cell lung cancer (NSCLC) patients whose tumors were refractory to standard therapy, and the results demonstrated that T-DXd showed durable anticancer activity with a median PFS of 9.3 months.22 Up to now, no clinical trial has been designed to specifically examine the efficacy of ADCs in treating HER2-mutant BC. Here, ERBB2 is linked to breast cancer.