Menopausal hormone therapy and risk of biliary tract cancers: addressing the ant, not the elephant in the room.

Sex hormones are responsible for multiple physiologic processes by signalling through estrogen (ER) and androgen receptors (AR).(1) ERs and ARs are expressed in liver and biliary tract cells in normal and diseased states in both men and women. Thus, the liver is recognized as a sex hormone responsive organ. In general, estrogen is associated with hepatic "protection" while androgens associate with hepatic "progression".