TACSTD2 and breast cancer: The protein expression of TROP2 by IHC in BC varied according to the molecular subtype, with significantly higher expression in HR+/HER2− BC and TNBC as described in a few studies, alongside ours.21,22 In our study, all the patients with HR+/HER2− BC showed TROP2 protein expression by IHC, with intermediate and high expression in 68.57% and 31.43%, respectively.