EZH2 expression in ER-positive cases with moderate to high proliferative index or HER2 positive breast carcinoma was variable in both intensity and quantity, and 51.2 % (21/41) and 51.4 % (19/37) showed strong EZH2 overexpression with a maximum score of 9 in these two cohorts respectively. The gene discussed is EZH2; the disease is breast carcinoma.