When assessed by the molecular subtype of breast cancer, the mutation prevalence was 19.0% in patients with hormone receptor(HR, +)Her2(−) breast cancer, 20.0% in patients with HR(+)Her2(+) breast cancer, 0% in patients with only Her2(+) cancer, and 45.5% with TNBC (p = 0.024). The gene discussed is ERBB2; the disease is breast cancer.