ERBB2 and breast carcinoma: Regulatory agencies have already approved ICB for several malignancies, including triple-negative breast tumors (atezolizumab and pembrolizumab, Schmid, P.; 2018); however, HER2-positive breast cancer had not been studied extensively until recently due to the variety of available therapies and the initial thought that HER2-positive breast cancers were not immunogenic [43].