As with @Sister - I've also wondered if the removal of ovaries (in my case, 10 years post menopause - 20 years since the start of menopause) may prevent or reduce the requirement for AIs and at the same time, obviously prevent one of the most difficult cancers to detect from even occurring - Ovarian Cancer.
I am aware that some estrogen is also created from our own fat reserves that would need suppressing.
I wonder if any researchers have looked into this - from women who HAD to have ovaries removed and incidences of breast cancer within that group?
Obviously, the earlier the age of ovary removal, the more chance of osteoporosis - but at this point in time, with modern medicine & scanning methods to monitor bone density - it could be an option to explore or at least, worthy of research.
After all, it IS estrogen that is feeding most of our BCs