PR positive

Definition of progesterone receptor positive
National Cancer Institute

progesterone receptor positive

(proh-JES-teh-rone reh-SEP-ter PAH-zih-tiv)
Describes cells that have a protein that binds to the hormone progesterone. Cancer cells that are progesterone receptor positive may need progesterone to grow. These cells may stop growing or die when treated with substances that block the binding and actions of progesterone. Also called PR positive.

Source: NCI Dictionary of Cancer Terms