Tamoxifen vs. AI =question

MelDent

HI-

Newbie here and have talked to my Dr. about an estrogen blocker. I am in perimenopause and he suggested that he can put me into menopause with a shot and then start me on AI, instead of doing Tamoxifen.

Has anyone done this? He said that he would use a shot, about once a month.

Any advice?

Thanks!

Kicks

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.

beach2beach

I can't comment on it, but I'm in perimenopause also and will start Tamoxifen. My Onco said once i go through meno she will switch me. I'm 51, who knows when that will be.

I've not heard of that option. I'm curious to learn more.

SpecialK

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

Castigame

Special K,

thank you in advance for your input w your expertise.

I have come to realization and acceptance that I will be on a hormonal blocker. I am 47. BMX done chemo done rad almost done total hyst scheduled two wks after MO follow up. My question is should I ask for AI rather than Tomoxifen?

Mimi

MelDent

Hi Mimi,

The Tamoxifen blocker works on all estrogen in the pre-menepausal body. AI's are used in women who no longer have estrogen produced in the ovaries.

If your hysterectomy includes the ovaries, then you'll be fine on AI's, from what I've researched.

Hope that helps. Wishing you well on your journey.

Michelle_in_cornland

Tamoxifen works on pre and post menopausal women. It has less side effects and is easier to tolerate. If you have any bone loss, I have some hip osteopenia, Tamoxifen is the better choice. There is not much of a significant difference in recurrence, but there is a slight one. I had a hysterectomy/oopherectomy and am so glad that I did. Best choice for me. Had discussed shots, which I would have been on for at least 2 years. I feel great, and have not felt this good in a long time. Tamoxifen actually makes me feel better. I have lost 40 pounds in a year since diagnosis, and have more to go. My bone health is very important to me, and I am not willing to sacrifice my future skeletal health for a one percentage risk increase.

ChiSandy

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.

brigid_TO

Hi ChiSandy You have made the claim that Tamoxifen may cause retroperitoneal cancer in another post and at the time I couldn't find anything to support that claim. I now see it again and am hoping you might have a reference to provide. Thank you.

MelDent

Thanks so much Michelle and ChiSandy. What a wealth of information!!!

I'm so thankful for this site and being able to hear all of the pro's and con's from those who have been there!

Melissa