Aromatase Inhibitors, the "Hormone Blocker": 3 years on....

In my patient support groups and online social breast cancer circles, I read many comments a day asking about whom has chosen to take these, who chose to forgo them, and how patients are considering "quality of life" over these drugs. I have now been on letrozole (Femara) 2.5 mg per day for three years and three months. I don't think I've missed a single dose. I don't like anything about the drug or its side effects, and there are many. But I like the idea of dying from cancer even less - so I take it every day, and I'm hoping someone reading this post will decide to stick with it too. 

I'm in no way suggesting these are easy drugs to take, or that the total and complete cessation of estrogen is easy to tolerate. When natural menopause occurs, there is still some circulating estrogen from adipose (fat) tissue to help ease the effects on bones, joints, and nerves. With aromatase inhibitors, it's next level estrogen deprivation, to the points of complete absence, and that's what causes worse "menopause" than the natural - the arthritis, the crippling joint pains, the vaginal dryness and pelvic symptoms - all are worse than they might  have been if we had been allowed to naturally progress to menopause. So yes, it's worse. 

And yes, these side effects are real. They cause decreased quality of life, pain, and it's understandable why women question taking them. So if you are early in your journey, and considering whether to take AI's, here are a few reasons you might want to: 

1. Not everyone has side effects, and if they do, sometimes they are better with time. Try the drugs for a few weeks, and see how you do. Don't anticipate you will automatically have every side effect you've read or heard about. Furthermore, there are three different AIs to choose from - if one is intolerable, take a break then try the next one. Many patients report different side effects from the three, so it's worth trying a second or third drug if the first one is intolerable. 

2. Many side effects are manageable - the arthritis and joint pain are truly manageable with movement, heat, and anti-inflammatories. If I skip yoga or my tart cherry supplements, my arthritis is immediately worse. But exercise every single day, sauna sessions, hot showers, and tart cherry supplements really do help. The pelvic symptoms can be mitigated with suppositories, lubricants, and PT. Yes, there are risks of osteopenia, osteoporosis, and exacerbation of high cholesterol and cardiovascular disease. And some of these do require more drugs to treat (I've done the zometa infusions, and now am on prolia for osteoporosis). No one wants to take more drugs to treat side effects of other drugs - but no one wants to die of cancer either. And the drugs for stage IV cancer have a whole lot more potential badness than many of these. 

3. It won't last forever - yes, it'll stink, and it might be 5 years, or even up to 10. Currently there seems to be no benefit for most patients past 7 years, and many of the side effects will improve once the medication stops. Some won't because menopause is forever, but the drug itself won't be forever. 

4. Because you don't want to die of cancer. My own personal choices on this journey have been made by that overarching goal: I want to die of NOT cancer. I will read literature, evaluate data, and look at studies - and as long as there's evidence that something will decrease my risk of cancer recurrence, I will do it. Maybe because I was 45 at diagnosis, I'm looking at things with a longer lens than someone diagnosed at 70, for whom a good 5 years now is worth 20 more years of life later - and that's OK. But the younger you are at diagnosis, the longer you will live under the specter of recurrence - and maybe the more likely you are to do everything. Not since tamoxifen has there been a major breakthrough in hormone positive early stage breast cancer until aromatase inhibitors. They remain the best tools in the toolbox for post menopausal women with HR+ breast cancer - and for lobular breast cancer, they've shown some benefit over tamoxifen for recurrence prevention. This is the best we have - and I never wanted to look back and wish I could've done something more in the face of recurrent or metastatic breast cancer. 

Below are a few of the studies showing the survival and recurrence data of these drugs if you want to read some data for yourself - but I encourage you to read the science, not the stories, and to see for yourself how you do before you decide not to pursue treatment with these drugs. 

1) Early Breast Cancer Trialists' Collaborative Group (EBCTCG). Aromatase inhibitors versus tamoxifen in early breast cancer: patient-level meta-analysis of the randomised trials. Lancet. 2015 Oct 3;386(10001):1341-1352. doi: 10.1016/S0140-6736(15)61074-1. Epub 2015 Jul 23. PMID: 26211827.

2) D'Onofrio R, Omarini C, Toss A, Sperduti I, Piacentini F, Barbolini M, Cortesi L, Barbieri E, Pettorelli E, Chiavelli C, Dominici M, Moscetti L. Adjuvant Endocrine Therapy in Premenopausal Women With Hormone Receptor-Positive Early-Stage Breast Cancer: Risk Stratification in a Real-World Setting. Clin Breast Cancer. 2023 Oct;23(7):712-720.e3. doi: 10.1016/j.clbc.2023.06.013. Epub 2023 Jul 7. PMID: 37507257.

3) Mamguem Kamga A, Billa O, Ladoire S, Poillot ML, Jolimoy G, Roignot P, Coutant C, Desmoulins I, Maynadie M, Dabakuyo-Yonli TS. Trends in endocrine therapy prescription and survival in patients with non-metastatic hormone receptor positive breast cancer treated with endocrine therapy: A population based-study. Breast. 2021 Oct;59:79-86. doi: 10.1016/j.breast.2021.06.003. Epub 2021 Jun 11. PMID: 34174766; PMCID: PMC8242053.