Breast cancer
posted by CMarvelJ
15 November 2020

Pre-Existing Endometriosis and Hormone Treatment

Last reply: 2 months ago

Hi all,

It is 18 months since I was diagnosed with Breast Cancer (Triple Positive). A mastectomy (Including lymph node clearance) in May 2019, Chemo (AC and Taxol), Radiotherapy and Herceptin all behind me.

Each of these was a challenge, however the biggest unexpected challenge for me is Tamoxifen. I have a history of Endometriosis which had calmed down, however when I started Tamoxifen in August it triggered the worst symptoms of Endometriosis I ever had within a matter of days. This was only addressed through stopping the course as agreed with the Oncologist. It hasn't gone away, but it is manageable.

I am 48 years old and in peri-menopause. I am at a crossroads and I have no idea where I go from here. When I look up alternatives to Tamoxifen all I can find is solutions for Women who are post menopause. I cannot go through the pain again, there is no point in taking a medication if the side effects are impossible to live with, for me it was worse than the chemo.

I am hoping that somebody out there has been on similar journey and has some advice, some information that can help me understand a way forward, before I meet my Oncologist in a weeks time.

Many Thanks

1 comment


commented by Cancer Nurse
03 December 2020

2 months ago


I am sorry to see that you didn’t get a reply from other ladies whose hormone therapy exacerbated their pre-existing endometriosis. Having been through so much this additional complication must be so hard to deal with . I hope that by now your oncologist and maybe gynaecologist have been able to advise you on what is best to do.

If you would find it helpful to phone our support line and speak to one of our nurses and maybe also speak to a counsellor for extra support do not hesitate to phone us at 1800 200 700. We ae here Mon-Fri 9-5pm.

Kind regards

Cancer Nurse

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