Immunohistochemical (IHC) analysis revealed the following biomarker expression profiles in the 100 DCIS cases: estrogen receptor (ER) was positive in 64% and negative in 36% of cases; progesterone receptor (PR) was positive in 60% and negative in 40%; human epidermal growth factor receptor (HER2/neu) was positive in 41% and negative in 59%; androgen receptor (AR) was positive in 77% and negative in 23%; and epidermal growth factor receptor (EGFR) was positive in 36% and negative in 64%. The gene discussed is ESR1; the disease is ductal breast carcinoma in situ.