Fig. 4
From: Intratumoral heterogeneity as a source of discordance in breast cancer biomarker classification
Representative images of cases with discordant ER, PR, and HER2 status between any two cores from the same case due to presence of benign epithelium (arrows for ER, PR) and clinging ductal carcinoma in situ (HER2). Percentage of ER- and PR-positive cells or HER2 status is indicated for each core. ER estrogen receptor, HER2 human epidermal growth receptor 2, PR progesterone receptor