TEST ACRONYM

FULL TERMINOLOGY

Estrogen Receptors / Progesterone Receptors

DEFINITION

Hormone receptors are located on the outside of cancer cells and pick up signals that "turn on" growth in breast cells that have receptors.

ER-positive cancer has receptors for the hormone estrogen.
PR-positive cancer has receptors for the hormone progesterone.
Breast cells that do not have receptors are "negative" for these hormones.

WHEN TEST WOULD BE PERFORMED

Tests will be performed on the tumor sample to determine the hormonal status and reported in the pathology report.

INFORMATION VALUE

Breast cancers that are either ER+ or PR+, or both, tend to respond to hormonal therapy. They can be treated by medications that reduce the estrogen in your body, and may also be treated with medicine that keeps estrogen away from the receptors.

CAUTION

Hormone status is typically written as a percentage (ie.80%/30%) or a number between 0 and 3. If your pathology report simply states "negative", ask your doctor or lab to provide a number. Even cancers with low hormone status numbers may respond to hormonal treatment.