BreastCancer.org

mobile

Search

Back to Dictionary: E

ER+ [also called estrogen receptor positive]

(ee-are POZ-uh-tiv)

Breast cancer cells that have estrogen receptors. Estrogen receptors are special proteins that the hormone estrogen binds to. Breast cancer cells that are ER+ depend on estrogen to grow. Anti-estrogen hormonal therapy blocks the receptors or reduces the amount of estrogen that can get into the receptors. As a result, the cancer cells may shrink or die.

Read more about hormone receptor status.

Audio contributed by: Marisa Weiss, M.D.

Who We Are

Breastcancer.org is a nonprofit organization dedicated to providing the most reliable, complete, and up-to-date information about breast cancer and breast health as well as an active and supportive online community.