Weakly ER+, PR-, Pre-Menopausal... Tamoxifen, AI or neither?

bluefin

Hi everyone,

I have most of my history in my signature. I had a PCR from chemo, but still did a bilateral mastectomy and radiation due to the aggressiveness of the tumor and because I am BRCA1+. My MO puts my risk of recurrence at less than 10%, but can't be more specific than that. It could be 2%, 9%, 5%, or anywhere in between. All he knows is with my response to chemo, the risk of recurrence is lower than if there were some type of residual cancer burden at the time of surgery. MD Anderson's website gave me an 88% disease free survival for both 5 year and 10 year because of the PCR, regardless of tumor characteristics.

I am still pre-menopausal (cycles returned 2 months post chemo) and my MO is still recommending Tamoxifen, although he expects only a modest benefit for me as I am weakly ER+ (17%). He said that I could have up to a 40% risk reduction from Tamoxifen, but probably not that high because of my low ER+. If my risk were 10%, that would bring my risk down to 6%, but if my risk is 5%, we're only taking about a reduction from 5% to 3%.

He is also recommending I do a monthly Lupron/Eligard shot in addition to the Tamoxifen to suppress my ovaries, as that has shown to be "more effective", although I found conflicting data about that when researching myself. He said I can also do an AI instead of Tamoxifen if I do the ovary suppression, and that has shown to be most effective (up to 50% risk reduction), however he was sticking by Tamoxifen because the difference between the benefit from Tamoxifen and the benefit from an AI is only about 1 - 2%.

I asked about Tamoxifen not being as effective on ER+ PR- tumors as ER+ PR+ tumors and he agreed, but he still feels there is some benefit for me. I also asked about the CYP2D6 enzyme testing to see how well I would metabolize Tamoxifen and he doesn't offer that test. I found a study suggesting data on the CYP2D6 enzyme is flawed anyway.

I can't make up my mind what I want to do. I never want this cancer to come back, but at the same time I don't want to do a hormonal treatment that may not be effective on my type of tumor. I really like my oncologist, but I know he's partly recommending these treatments because he has to. There are scary side effects for both drugs and if I were strongly ER+ and/or didn't do radiation and/or didn't have a PCR I wouldn't be questioning hormonal treatment as much as I am. Part of me is leaning more towards doing an AI over Tamoxifen, as I want to have more children, and the potential uterine changes from the Tamoxifen are more bothersome to me.

My MO called the script in for Tamoxifen and I was supposed to start yesterday, but the pharmacy said it's back ordered so they don't have it yet.

Any insight?

ruthbru

I was only mildly ER positive (25%) and PR negative. I was recommended to take Arimidex for 5 years, and did so. As they explained to me, it's like being a little bit pregnant.....you are or you aren't. I don't know which drug you should take, but I would definitely take something; especially the first couple years, which are the most risky in terms of recurrence.

ShetlandPony

Bluefin, congratulations on your fantastic response to chemo. I'm sorry you have to make such hard decisions. Don't let the oncologist put the burden all on you. A second opinion might help you feel more settled. I can think of a few things you might want to investigate and discuss with your onc.

It might be the case that CYP2D6 testing is more important for premenopausal bc patients. The abstract for the article CYP2D6 and adjuvant tamoxifen: possible differences of outcome in pre- and post-menopausal patients concludes "In a subgroup analysis, the effect of CYP2D6 seemed to derive mainly from premenopausal patients, which represents a new finding that needs validation in a larger study sample." http://www.ncbi.nlm.nih.gov/pubmed/23570465/

Look at the results of the SOFT trial. It addresses which premenopausal women should have OS + AI vs. Tamoxifen.

You could try the lupron plus aromatase inhibitor first and see how you tolerate it. It is not a decision set in stone. I guess your plan is to do some years of hormonal therapy, then have that baby, then consider an oophorectomy because of the BRCA1+?

bluefin

ruthbru - That makes sense about either being positive or negative, and less so about the strength of the positivity. Thanks for that!

ShetlandPony - Reading through the SOFT trail, I think I would be one of those that would benefit more from OS + AI since I also received chemotherapy, under 35 and still pre-menopausal. My MO said that he would want to do Lupron first, wait a month or two to do bloodwork to confirm ovaries are "shut down", then start AI if I went that route.

Yes my plan is to take a break from hormone therapy after 2 - 3 years, have the baby, then complete treatment. I'm wondering if I should consider 2 years of OS + Tamoxifen, take a break to try for pregnancy, and then do 3 years of OS + AI? Then I would have benefits of both and less toxicity from each? I don't know if my train of thought makes sense, but with the added benefit of the OS + Tamoxifen (which it seems there is in my case), but the OS should in theory also preserve what fertility I have left since I won't be ovulating?

I do plan on an oophorectomy after I'm doing having children, around age 40. My MO said it's best to not do it now because I'm too young and the side effects of them removed at this age outweigh the benefit since my ovarian cancer risk is still relatively low at age 32.

ruthbru

Is there any way you could find a doctor who has an expertise in this area? An OB or fertility doctor who has dealt with these issues in their practice? It seems that any advice that we give would just totally be a guess.

ShetlandPony

Bluefin, switching from tamoxifen to an aromatase inhibitor or vice-versa has been studied quite a bit. I think I would ask the onc about which order would be better in your case. I wonder if doing the more aggressive treatment (OS + AI) first would be best. I think that you need to get as much expert advice as you can because your situation as a BRCA+ premenopausal woman who desires more children is not the common one. Ideally you would consult a medical oncologist, a fertility specialist/gynecologist, and a women's cancers geneticist, and ask them to confer with each other in devising the best treatment plan for you. I don't know where you are being treated, but if you have access to a NCCN medical center with these specialist working together, all the better.