Hormone receptor-positive (HR+) is a subtype of breast cancer that includes both estrogen receptor-positive (ER+) and/or progesterone receptor-positive (PR+) subtypes and grows in response to 2 different hormones—estrogen and/or progesterone.4 If your cancer grows in response to the hormone estrogen, your cancer could also be called ER+.4 If your cancer grows in response to the hormone progesterone, it could be called PR+.4