TSWAHL: Is the use of progesterone cream safe after breast cancer and is it effective if the tumor was PR-neg? Dr. John R. Lee: The test for progesterone receptor presence or absence is not a very accurate test. Progesterone receptors are stimulated to be made by estrogen itself. It is highly unlikely that any tumor driven by estrogen would have no cells that lack progesterone receptors. If there in truth were no progesterone receptors then it could do no harm because the cell could be unaware that any progesterone is present. Chances are the receptors are there, and therefore the cell will respond to the message of progesterone which is a prevention against breast cancer. If a phone line came by your house, but you didn't have a phone, you would be unaware of it -- that's how it is with progesterone. The message of progesterone to breast cells is to stop them from becoming breast cancer cells. So therefore, there is no reason ever to not give progesterone to try to help someone prevent or stop breast cancer. In 3,000 breast cancer biopsies Dr. Zava found only one in which there were truly no progesterone receptors. It's a rare congenital defect. Dr. Lee has written a paper: Annals of Clinical and Laboratory Science, 1998, Vol. 28, page 360, June. "Progesterone inhibits growth and induces apoptosis in breast cancer cells: Inverse effects on Bcl2 and P53." Ann's NOTE: We were unable to access this journal online. If anyone can get this article, please email it to us and we will post it. And according to his associate, Brent Formby, he has two more papers about to be published. From a powersurge.com chat in March, 2002 Article references found here LINK to his site LINK to site for menopausal information Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.