[AlaskaAngel]

Hi Rebecca,

The reason for putting people like us on drugs like aromatase inhibitors (like Arimidex, Femara, and Aromasin) or on SERMS (like tamoxifen) is to reduce the production of estrogen, or block it from having much effect.

But the problem is that for some people who take these drugs to reduce the effect of estrogen, eventually resistance to these drugs is believed to develop. It can happen to anyone who is taking these drugs.

The studies we are talking about are being done on patients who have had metastasis. The studies are being done to see if the use of estrogen for a period of time (after the aromatase inhibitors have failed and the patient has developed resistance to the AI's) affects the cancer by slowing it down, and acts to "resensitize" the patient so that the aromatase inhibitors might work again for them.

There is no way to tell whether anyone is developing resistance to use of an AI, other than recurrence/metastasis. It can happen to anyone. If we could tell when it is happening without having to see metastasis, then possibly we might be able to stop them from taking the AI for a period of time, and use a course of estrogen to "resensitize" that person, so that maybe the aromatase inhibitor might work again. It would be helpful if we knew when to stop giving the aromatase inhibitor in patients who have not yet developed metastasis/recurrence, but are developing resistance to the AI. That is what the research is trying to figure out. They are trying this idea out first with patients who have had metastasis, to see if using the estrogen intermittently and then an AI again works well or not.

These studies indicate that the use of estrogen may make very good sense for those people who develop resistance to aromatase inhibitors while taking the AIs.

AlaskaAngel