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Very High Estradiol Levels


I am about a year and a half out from my breast cancer diagnosis and treatment. I have been taking tamoxifen since November of 2022. I had a hysterectomy in Sep. Of 2023 because of excessive bleeding caused by the tamoxifen. My surgeon left one ovary ( I only had one due to having the other one removed years prior ). I had my hormones checked in July of 2023 and my estradiol level was 75. I just got it checked last week and it is now 1908 which is very high. Has anyone here had this happen while on tamoxifen? My doctor is ruling out any issue with my ovary and checking my CA125 because ovarian cancer can cause this to happen. She also mentioned that tamoxifen can cause this but what I am reading is that it would not be this high. Has anyone had this happen and if so did they figure out if it was the tamoxifen causing it? I do not want to have to go off of the tamoxifen but my cancer is very ER+ so all of this estrogen if not good. Any information would be very appreciated.


  • moderators
    moderators Posts: 8,283

    Hi @rnjen, we welcome you warmly to our community. We are not doctors, so really don't have the information, but have you discussed a possible drug resistance to the Tamoxifen with your treatment team? If that would be the case there are 3 Aromatase inhibitors that you could discuss as alternatives .

    We're here for you ❤️

  • purplecat
    purplecat Member Posts: 226

    @rnjen, this happened to me after about a year on tamoxifen. I think my level was over 800. I searched the forums at the time and found several other women who had experienced the same from tamoxifen, with levels even higher than mine, so I wasn't terribly concerned about it and figured it was a fairly common issue. Apparently not, as my team fast-tracked me to an ultrasound and blood tests and the whole terrifying gyno cancer workup. Long story short, I ended up with a full hysterectomy, but not the tiniest speck of cancer was found.

    I tried to search the forums just now to find an old thread or two about this issue, but nothing is showing up. This was well before the forums were updated, so maybe older threads are harder to find now. But I definitely remember that other women had reported this problem and none of them turned out to have ovarian cancer.