Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs. Hormonal therapies interfere with the way hormones are made or how they work in the body.
Many cancers need hormones to grow. Medroxyprogesterone is a man-made drug that is similar to the female hormone progesterone. Doctors think it may work by interfering with the hormone balance in the body. This may stop the cancer growing.