Similar to previous studies,10–16 we observed that higher TIL density (CPath TIL-high) was associated with larger lesion size, higher cytonuclear grade, presence of necrosis, lack of ER expression, and HER2 over-expression, all of which are adverse prognostic indicators in DCIS.19,20,24 However, CPath TIL categories remained independently prognostic in multivariate analyses. Here, ERBB2 is linked to ductal breast carcinoma in situ.