Post surgical menopause - oestrogen reducing medication query

HI Sarah16

There are different types of oestrogen medicines.  Tamoxifen is usually for those pre menopausal as it works on the ovary production as well.  Anastrozole and Letrozole for post menopausal.  I am on Anastrozole and I still don't know how they decide between these 2.  (I wonder if it's when you are very close to having gone through menopause - I was 51 when diagnosed and had just gone through it, but who knows!)

However, the ovaries aren't producing oestrogen due to the menopause, so the oestrogen that is produced is by a hormone called aromatase which changes androgens into oestrogen. So if someone is post menopause and is ER+ (oestrogen positive), the aromatase inhibitors are given to prevent this - the Letrozole / Anastrozole drugs.

Hope this helps.

Best wishes, Lesley.

Hi Sarah

Just to add to what Lesleyhelen has said. I think in we postmenopausal women oestrogen production occurs in our fat, not our ovaries. I was started on Letrozole and took it for about 6months and was doing quite well on it until, I started to get stiffness, aches and swelling of my knuckle joints to the point that I commented to my onc that I didn't think I would be able to drive in the mornings(symptoms did get better as the day progressed as long as I kept hand moving). Onc immediately suggested i try exemestane which is a different type of oestrogen inhibitor. She said it would take about 8weeks for the letrozole to wash out. I have noticed a gradual improvement and now have almost no hand issues. I think the exemestane is a steroid type molecule which works in a different way, but has the desired effect shutting off oestrogen production.

Sorry not to be more help.

WallyDug

Hi Sarah16, 

I don't think that it is uncommon for women with no ovaries to take oestrogen reducing meds . I had quite high lymph node involvement, so because of this and also because letrozole has been shown to be more beneficial than other oestrogen reducing meds against lobular bc, my onc wanted me to take letrozole. So that I could take letrozole, I had both my ovaries removed as I was premenopausal. Onc recommended that I take letrozole for 10 years - I will be up to 5 years in the summer. AIs are only prescribed for postmenopausal women so their ovaries are not producing any oestrogen anyway. 

I think the dosage for AIs is a standard amount in any brand, so I would assume you would just be prescribed the standard dose. However it does seem as there are different doses of tamoxifen. 

Cwtches, 

Gay xxx

I didn't realise that oestrogen was also produced in fat tissue until I had breast cancer. I was pre menopausal and was given the choice of taking tamoxifen or having an implant every 4 weeks to stop my ovaries working (a medical menopause) and then also taking an aromatase inhibiter. I opted for the latter so I'm similar to you in that my menopause is not a natural one (I could also request ovary removal) but I still need to take another hormone suppressant on top.