HORMONAL RECEPTORS, HUMAN EPIDERMAL GROWTH FACTOR RECEPTER-2, AND KI67 DISCORDANCE BETWEEN PRE-CHEMOTHERAPY BREAST CANCER AND PAIRED POST-CHEMOTHRAPY Objectives: To evaluate the changes of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor 2 (HER2), Ki-67 expressions in breast cancer before and after chemotherapy.