My mom had a breast removed 6 weeks ago due to breast cancer. She is 80. At her appointment today, the Dr. prescribed Arimidex. She told us that the tamoxifen has been linked to causing cancer of the uterus and since my mom still has all her female organs that she is better off on the arimidex. It is a hormone treatment that has had excellent results. She has to take it for 5 years. As for the side effects, she will start taking the pills tomorrow so we don't know anything yet. The Dr told her that the side effects were very minimal. Yes, they are very expensive pills. The cheapest we found them was 185.00 for a 30 day supply of the 1mg. The 185.00 was with senior citizen discount. One drugstore I called wanted 266.00. Good luck to you and if you can afford the Arimidex, that is the way I would go.