Tamoxifen vs. AI =question

There will be others who can give you info that I can't - I was 19 yrs post menopause when DX so not an issue for me at all. When on Femara at the start and went to the generic from -letrozole - when it became available in generic. Have been on it for 7 1/2 yrs.

These studies are one of the reasons that some oncologists use this option. It tends to provide better recurrence prevention in women who are younger, and thus farther away from natural menopause. Ovarian suppression can be done with Lupron or Zoladex, or you can opt for oopherectomy.

http://www.ascopost.com/issues/june-25-2014/exemestaneovarian-suppression-reduces-recurrence-vs-tamoxifenovarian-suppression-in-premenopausal-breast-cancer/

Here are some other threads from this site regarding this:

https://community.breastcancer.org/forum/78/topics/854598?page=1#post_4955722

https://community.breastcancer.org/forum/78/topics/852552?page=1

https://community.breastcancer.org/forum/78/topics/851434?page=1

Postmenopausal women in general have an elevated risk for cardiovascular disease (still the #1 killer of women, even bc patients). Tamoxifen raises the risk of blood clots, which could cause heart attack or stroke. It also either accelerates ripening of existing cataracts (more so than do AIs) and can initiate the appearance of cataracts (which AIs don’t do). Tamoxifen is inferior to AIs in increasing recurrence-free survival. Its only undisputed advantage over AIs is bone health—it can strengthen bones whereas AIs (which reduce the amount of estrogen in the body) weaken them—but there are drugs to counteract that. And it can cause endometrial cancer in those who still have uteri (and I forget where I read it—Susan Love, perhaps?—after hysterectomy, perhaps retroperitoneal cancer).. If you are about to enter surgical menopause, AIs are the better choice.

As to side effects, as many women have trouble tolerating Tamoxifen as they do any of the AIs. Weight gain, joint pains and hot flashes can happen with either class of drugs. The two classes (SERMs & AIs) fight ER+ bc by two different mechanisms & enzymatic pathways. SERMs (Tamoxifen) restrict the tumor cells’ access to estrogen—whether produced in the ovaries or synthesized by white fat cells + adrenals. Tamoxifen does not reduce the amount of estrogen in the body. (Hence, the elevated risks for blood clots & endometrial hyperplasia & cancer). AIs impair the action of aromatase, which when unimpaired acts as the catalyst for conversion of the androgens produced by the white fat cells and adrenal glands. AIs’ side effects are essentially the continuation or progression of those of menopause & estrogen reduction.

You can’t know what your side effects will be, nor how extensive nor how well you can tolerate them, unless you try. And there are certain meds such as bupropion and several SSRI antidepressants that are contraindicated with Tamoxifen.

The only reason for a postmenopausal woman to take Tamoxifen is inability to tolerate any AI (and any mfr. of any of them). Half a loaf is better than none, “none” being noncompliance.