Clinical benefit in our study was greater in patients treated with IO plus chemotherapy and this finding was observed in patients with both endocrine-resistant HR-positive/HER2- breast cancer and TNBC which is also consistent with other studies in breast cancer demonstrating modest response rates with IO agents alone (16, 17, 19, 20, 26, 29, 30). The gene discussed is ERBB2; the disease is breast cancer.