Refusing Hormone Therapy for Breast Cancer: What Are the Risks?
By Sarah Friend, MD
Hormone therapy can be one of the most effective tools we have in the treatment of hormone receptor-positive breast cancer. But it’s also one of the most commonly refused or discontinued treatments—often because of side effects, fears, or confusion about how it works.
If you’re considering stopping or refusing hormone therapy for breast cancer, this article is here to help you understand the risks so you can make a fully informed decision.
What Is Hormone Therapy?
Hormone therapy (also called endocrine therapy) is hormone blocking therapy that is used to lower the amount of estrogen in the body, or to block how estrogen affects breast cancer cells. It’s most commonly prescribed for breast cancers that test positive for estrogen receptors (ER+), and sometimes progesterone receptor (PR+). These cancers use hormones like estrogen to grow. The treatment for these cancers, therefore, involves blocking the hormones to create an environment in the body where estrogen positive cancers do not grow as well.
Common hormone therapy medications include:
- Tamoxifen – can be used in premenopausal or postmenopausal women
- Aromatase inhibitors (AIs) – can be used in postmenopausal women or premenopausal women using ovarian function suppression (OFS)
- Femara/letrozole
- Arimidex/anastrozole
- Aromasin/exemestane
- Ovarian function suppression (OFS) – turning ovaries off in premenopausal women using monthly shots (lupron, zoladex) or surgery to remove the ovaries (BSO, bilateral salpingo-oophorectomy)
What Does It Actually Do?
Hormone therapy isn’t chemotherapy—it doesn’t “kill” cells directly. Instead, it works more like a lock and key: if estrogen is the key that unlocks growth in certain breast cancer cells, hormone therapy is the way we change the lock.
It’s often used after surgery and after chemotherapy or radiation if those are recommended. Endocrine therapy lowers the risk of cancer coming back. And it works. In fact, endocrine therapy has been shown to:
- Cut the risk of cancer recurrence by up to 50%
- Lowers the risk of dying from breast cancer
- Provide long-term protection—even after treatment ends
What Are the Risks of Refusing Hormone Therapy for Breast Cancer?
The decision to skip or stop hormone therapy is personal—but it’s important to know the potential consequences.
Here’s what studies show:
- Patients with ER+ breast cancer who don’t take hormone therapy have a higher risk of recurrence, especially in bone, lymph nodes, or other organs
- The risk of death from breast cancer increases in those who skip this therapy
- Even lower-risk or early-stage cancers can return if estrogen remains active in the body.
While no treatment is without side effects, refusing hormone therapy removes one of your biggest defenses against future cancer.
Why Do Some Women Stop or Decline It?
There are valid reasons why people struggle with hormone therapy. Side effects can include:
- Hot flashes
- Joint pain
- Mood changes
- Vaginal dryness or sexual changes
- Fatigue
- Bone thinning
- Hair thinning
- Weight gain
- Elevated cholesterol
And those symptoms can be life-disrupting. But in many cases, there are solutions. There are medication switches, dose adjustments, and supportive therapies that can ease the burden. You don’t have to suffer in silence—or give up entirely.
What If I Already Stopped Taking It?
If you’ve stopped hormone therapy, it’s not too late to talk to your doctor. In many cases, restarting or trying a different medication is possible. There’s no shame in needing help or changing course. What matters is staying engaged and empowered in your care.
My Take as an Oncologist
As a breast cancer specialist, I’ve seen hormone therapy save lives—quietly and powerfully, over time. I’ve also seen how hard it can be to stick with it. While soul searching on these difficult decisions, consider the unthinkable scenario of cancer recurrence. Would you regret your decision to stop the endocrine therapy? If the cancer recurs after stopping the medicine early, would you blame yourself? Or would you be comfortable with your decision because you had less side effects. These decisions can be difficult. That’s why I created myFriendMD. To give patients space to talk through these hard decisions. To help you understand what’s at stake, what’s negotiable, and what support options exist.
If you’re unsure about hormone therapy or facing hard choices, let’s talk. You don’t have to make this decision alone.
Ready for Your Next Step? Learn How to Manage Anxiety During Cancer Care
Making treatment decisions is just one part of your breast cancer journey. But what about the emotional side—especially the waiting?
If you’re feeling anxious while waiting for test results or next steps, you are not alone. In fact, many patients say this is one of the hardest parts of cancer care.
That’s why I encourage you to read this next:
“The Wait is the Hardest Part”: How to Cope with Anxiety While Waiting for Test Results for Cancer”
In this article, you’ll discover simple, effective ways to manage anxiety, find support, and feel more empowered throughout your care.
