Hi Sharon , I'm sorry to hear how your family has been affected by this vile disease, I lost my mum too it in 2003 and I was diagnosed in 2015, so far thankfully both my sisters remain clear but have annual mammograms. We have not been tested as I was told it was highly unlikely to be genetic as mine was a rarer Tubular BC although both mum and I were oestrogen positive so took Tamoxifen.
As you have discovered a family history doesn't automatically mean there is a genetic fault, often it's just sheer bad luck. My sisters have not been offered Tamoxifen as a prevention but I know some to do take it for this reason. It does have side effects but often they are minor and in your shoes I would most likely take it and see how you get on. It caused me to have painful joints to the point where I had to stop after 2.5 years but not everyone suffers like this so don't let that put you off trying.
#The following is based on my personal research and experience as a family member of a breast cancer patient - please consult your doctors/specialists before making any decision#
If you have had family history of breast cancer - or other cancer - on your mother's side (aunts, grandmother etc.) you can benefit from genetic testing for the BRAC1/2 genes. If I understood right you have checked and that's not a problem, so you are trying to deal with future uncertainty given that you are of higher risk than the 'average' woman.
A few things to note:
Tamoxifen is very good at protecting against ER+ breast cancers only. It will not address any endometriosis problems you have, and while it works for the overwhelming majority of women, there is no way of actually _knowing_ it works as intended. The side effects are usually tolerated so given the risk/rewards it may be a good idea to discuss it with your doctors. You do not need to have a period to be on tamoxifen, that is incorrect. You need to be aware that tamoxifen increases your blood clots risks and endometrial cancer risk.
A more heavy handed solution to address the risk of ER+ breast cancer would be to shut down your ovaries, either medically (e.g. Zoladex injections every month) or through oophorectomy (someone mentioned hysterectomy - that would be unecessary, an oophorectomy will do). Of course, you'd need to consider whether you still plan on having children and whether you are ready to enter menopause with all it's side effects. Shutting down your ovaries in any way will trigger immediate menopausal symptoms. They do get better over time (a few months down the line), but they can be hard to tolerate initially. The benefit of medically induced menopause (i.e. zoladex injections) is that you can stop at any time and will usually return back to normal after a couple months. Again, it's an option to discuss with your doctor(s).
However, besides any medical treatments you need to ensure you have the right screening in place. That can be mammograms and/or ultrasounds. Depending on your breast tissue density you will be directed to have one or the other, usually annually based on current NHS protocol. You can always opt to have both, every six months - if you can afford it privately. The most conclusive screening method remains an MRI with contrast, which again you could opt to do privately if you are very concerned, once a year. Physical examination by hand is also highly recommended as often as you can - many breast cancers start as lumps you can physically feel. Most times a lump is nothing of concern, but the earlier you go check it the better you will feel.
You mentioned family history of breast cancer but did not mention what type - that can have substantial impact on how high the risk you are in is. It would be a very different case if the history is that of ER+ cancer compared to it being triple negative.
Finally, with regard to the comment about estrogen produced through body fat. That is accurate. Around 10% of estrogen is produced by body fat, which is the reason post-menopausal women are given additional medication (e..g letrozole) to reduce that part of estrogen production even further. In pre-menopausaul you will usually get tamoxifen and some ovarian suppression (e..g zoladex).
I hope it helps, but again, make a list of questions and speak to your doctors. Do not take no for an answer and do your own research on whatever they tell you. Ask others but make sure your information is factual from research sources.
It is very natural to have lots of questions and fears at this time, everything is new, there is a lot of strange terminology.
When I was diagnosed I got myself a little notebook in which I wrote all my fears and questions down, so that when I next saw someone I had them there and would talk them through with my team, even after my op and rads, every time I thought of something I would write it down. It enabled me to get them out of my head and on to paper so that I would not forget them.
As with Jo, I was told the same that we hold some oestrogen in the fat in our bodies, because I questioned why I had to have them as I am very definitely post menopausal as I was 58 at the time of diagnosis.
Sending you hugs and we are all here for you my dear
Magsta I asked about having a hysterectomy but my Oncologist said there was no point as oestrogen is in our fat as well so can't be eliminated by removing our ovaries plus I was 46 at diagnosis and my levels would naturally be reducing, they do tend to do more to suppress oestrogen in younger ladies who are diagnosed.
Yes the side effects are there as with any drug, but having gone through breast cancer myself and taking tamoxifen as a preventative for it returning I would recommend it. It's obviously not an ideal scenario to be in, because noone wants to take a drug they don't need to, but in reality the side effects arent so bad that I wouldnt want to take it.
Hot flushes - they settle down after a while and you tend to find a brand that works for you eventually. I know I cant take the Mylan brand for example.
Periods - mine have got heavier and they last longer, but my cycle also got a lot longer too. Not all women have this though.
Ovarian Cysts - I am definitely someone who suffers with these continuously on tamoxifen, but not everyone does.
They are about the only side effects I get. And in truth, regardless, I still think it's worth taking.
I would suggest to you that you give it a try. Side effects vary enormously from one person to the next. Some sail through without any, some get them so severe they give up taking it. Most muddle through somewhere in between. Remember that people only usually post on forums when they are having problems, so you are getting a skewed view from that. Those who have no problems don't tend to report it. You can always give up if you don't like it. If you get side effects you don't like, then you will have to weigh up those against the risk of getting breast cancer - not any easy thing to do I know.