Supporting findings in previous reports [15,17-21,27,29,31,35-38,48,50,52,54-57], the majority of breast-ACC in the SEER Program was ER-negative/PR-negative; however, hormone receptor-positive tumors have also been described in a minority of cases [22,23,25,32,34,42,58]. The gene discussed is ESR1; the disease is adrenal cortex carcinoma.