Former First Lady Recovering From Hormone Therapy For Breast Cancer Treatment Says Despite Side Effects, She’s ‘Grateful,’ Urges Other Women to Get Yearly Screening

“Tamoxifen is a drug that has been used to treat breast cancer for decades. It is a medicine that is used for women who have estrogen receptor-positive breast cancer,” breast medical oncologist Dr. Elizabeth Comen explains to SurvivorNet.

An Italian-French singer, songwriter, and former fashion model who served as France’s first lady from 2008—following her marriage to then‑president Nicolas Sarkozy—until 2012. She continued her message expressing gratitude for the next chapter in her breast cancer journey.

 

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“Despite its sometimes aggressive side effects, I’m grateful for the science behind hormone therapy. It offers real protection against the relapses that are so common in the years after diagnosis,” she added.

Bruni’s Hormone Therapy Explained

Dr. Comen explains that some breast cancers are hormone‑receptor positive, meaning the cancer cells have estrogen receptors on their surface. “Imagine the cancer cell,” she says. “It’s got this receptor—almost like a keyhole—on the outside of the cancer cell. Estrogen is the key.”

When estrogen fits into that “keyhole,” she explains, “the lock turns, the door opens, and the cancer cell can grow.” In other words, estrogen acts like a “fertilizer” that helps these cancer cells multiply.

That’s where tamoxifen comes in.

Tamoxifen is designed to block estrogen from activating those receptors. Dr. Comen describes it this way: “For breast cancer cells, it blocks that keyhole—almost like putting a piece of gum into the keyhole—so that when the receptor tries to reach out and grab the estrogen and use it as that stimulus to grow, it can’t do that because the sticky gum is there.” This is why tamoxifen is called an antagonist in breast tissue: it prevents estrogen from fueling cancer growth.

But tamoxifen doesn’t act the same way in every part of the body. “In some instances, in other parts of the body, it can actually be an agonist,” Dr. Comen notes—meaning it can have the opposite effect and stimulate certain tissues. “That’s where some of the good and potentially bad side effects of tamoxifen can come in.”

Hormone Therapy: A Powerful Tool Against the Most Common Form of Breast Cancer

For many women diagnosed with breast cancer, the disease is fueled by hormones—specifically estrogen or progesterone. These are known as hormone receptor-positive cancers, and they represent the most common subtype of breast cancer.

Hormone therapy is designed to block or lower the hormones that help cancer cells grow. It’s a cornerstone of treatment for hormone receptor-positive breast cancer, and it plays a vital role in both treatment and prevention.

“Endocrine therapy has significant benefits in reducing the risk of breast cancer recurrence and improving breast cancer survival,” says Dr. Eleonora Teplinsky, head of Breast Medical Oncology at Valley Health System.

These therapies work in two main ways:

• Lowering estrogen levels in the body
• Blocking estrogen receptors on cancer cells so the hormone can’t fuel tumor growth

WATCH: Hormone Therapies for Breast Cancer: Aromatase Inhibitor

Types of Hormone Therapy

One widely used drug is Tamoxifen, which blocks estrogen’s ability to bind to cancer cells. It’s used not only to treat breast cancer but also to help prevent it in women with a strong family history or other risk factors.

Another class of drugs, called aromatase inhibitors, works by stopping the body from producing estrogen altogether. These are typically prescribed to postmenopausal women and include:

• Anastrozole (Arimidex)
• Letrozole (Femara)
• Exemestane (Aromasin)

All are taken as daily pills and have been shown to slow or stop the growth of estrogen-sensitive tumors.

Hormone Therapy Side Effects Can Mimic Menopause

Depending on the endocrine or hormone medication, each one may have its own side effects. Typical side effects for certain types of hormone therapy drugs may include:

• Bone pain
• Joint pain
• Loss of appetite
• Nausea and/or vomiting
• Fatigue
• Constipation

Bruni’s Breast Cancer Journey

Bruni was diagnosed with breast cancer in 2019, although she shared it publicly a little later.

During her initial Instagram post, she said, “I’m not writing this post to give you the details of my health. That’s repugnant to me, and I hesitated for a long time before talking about this. No, the reason I’m posting this today is to deliver a message.”

“Every year, on the same date, I do a mammogram. If I hadn’t done one every year, I wouldn’t have a left breast today,” she added, hinting at the need for a mastectomy.

A mastectomy is the removal of the entire breast during surgery. Several factors weigh into considering a mastectomy, including whether breast-conserving surgery (or lumpectomy) is possible.

Bruni underwent surgery, radiotherapy, and hormone therapy to treat her cancer. She stressed the value of mammograms, a standard breast cancer screening method.

Bruni hopes others hearing about her breast cancer journey follow her advice to stay current with health screenings.

“Hormone therapy is a pretty heavy treatment – but its effectiveness can save your life.
I want to say again to all the women reading this post, not to hesitate to get screened annually if possible,” Bruni said.

Breast Cancer Surgery

A lumpectomy is a surgery to remove cancerous or abnormal tissue from the breast. It’s also known as breast-conserving surgery because, unlike mastectomy, only the tumor and some of the surrounding tissue are removed.

WATCH: Choosing between a lumpectomy and a mastectomy.

A double mastectomy is a procedure in which both breasts are removed to get rid of cancer. The procedure may also be performed as a preventative measure for women who are at a very high risk of developing breast cancer.

“A double mastectomy typically takes about two hours for the cancer part of the operation, the removal of the tissue,” Dr. Elisa Port, Chief of Breast Surgery at Mount Sinai Health System, tells SurvivorNet. “The real length, the total length of the surgery, can often depend on what type of reconstruction [a patient] has.”

During a mastectomy, the breast is removed. In a double mastectomy, both breasts are removed. In many cases, women choose to undergo breast reconstruction.

Reconstruction gives women the chance to have implants put in right after the mastectomy procedure. However, some women choose not to have reconstruction at all.

Dr. Port told SurvivorNet that most women do opt to have some reconstruction. Depending on what sort of surgery a woman chooses, the time spent in surgery can vary greatly.

There are many different options and techniques available for reconstruction — from implants to using a woman’s own tissue — and choices about when to get the reconstruction, meaning immediate (at the time of mastectomy) or delayed (which could be months or even years later).

WATCH: Deciding to get saline or silicone implants during a breast reconstruction.

Immediate reconstruction can produce better results than delayed reconstruction, resulting in fewer surgeries. However, it may require a more extended initial hospitalization and recovery time. This long surgery may also have a higher risk of complications, such as infections, than two separate surgeries.

It may be worth noting that “Delayed reconstruction has fewer complications than immediate reconstruction,” Dr. Terry Myckatyn, a plastic surgeon specializing in breast reconstruction, told SurvivorNet.

When implants are used, the procedure can take two to three hours (so the total surgery time would be around five hours). During reconstruction, one can also take one’s own tissue (usually from the belly area) and transfer it into the breast area.

After breast cancer surgery, women diagnosed with early-stage breast cancer may also need chemotherapy, radiation, or hormone therapy.

Radiation Therapy: A Powerful Tool with Long-Term Considerations

Radiation therapy—using high-energy rays to destroy cancer cells—is a common follow-up to breast cancer surgery, especially for patients who choose a lumpectomy over a mastectomy. Its goal: reduce the risk of recurrence by targeting any lingering cancer cells in the breast or surrounding tissue.

While effective, radiation can come with side effects, both immediate and delayed. Common symptoms include:

• Fatigue
• Swelling
• Scar tissue
• Shortness of breath

RELATED: Cancer Patients With Dark Skin At Increased Risk of Painful Radiation Side Effects, New Research Says

One of the more serious concerns involves the heart, which can unintentionally absorb radiation due to its proximity to the breast.

“When the radiation is delivered, unfortunately, the heart happens to be somewhere very near to where they have their breast cancer, and it becomes an innocent bystander absorbing some of the radiation,” explained Dr. Jean-Bernard Durand to SurvivorNet.

This exposure can lead to complications such as fatigue, shortness of breath, and even heart failure—sometimes surfacing decades after treatment.

“We make it a point to see them on a regular basis so that we can catch these things very early and treat them,” Dr. Durand added.

Even advanced techniques like proton therapy, which aim to minimize damage to healthy tissue, aren’t immune to side effects. Fatigue remains a common complaint, and the risk of long-term injury still exists.

“Radiation is a form of energy… and when we give radiation, it has the ability to scatter,” Dr. Durand said. “Even though we may target one particular area, that scattering of energy can cause injury to the local surrounding structures, including the heart.”

Over time, this injury can lead to the development of scar tissue within the heart muscle, its electrical system, and blood supply.

“We believe it is what causes all the injury, that ultimately leads to the symptoms,” he explained.

For survivors, this underscores the importance of ongoing monitoring and open conversations with care teams.
Radiation treatment continues to evolve, with ongoing debates among experts about how to reduce side effects while optimizing outcomes. Dr. Chirag Shah, radiation oncologist and the division chair of Radiation Oncology at AHN Cancer Institute, outlined three key areas of discussion:

• Whole vs. Partial Breast Radiation: Shortening treatment duration and minimizing side effects are promising, though long-term data are still emerging.
• Identifying Patients Who May Not Need Radiation: Some individuals may not benefit from radiation, and omitting it could reduce unnecessary risks.
• Technique Optimization: Advancements in delivery methods aim to improve effectiveness while limiting harm to healthy tissue.

“I think the first debate that we have is whole breast radiation versus partial breast radiation and the idea of reducing duration of treatment and reducing side effects for patients, albeit with less than 10 years’ worth of long-term data,” Dr. Shah explained to SurvivorNet.

When to Screen for Breast Cancer

The medical community has a broad consensus that women should have annual mammograms between the ages of 45 and 54. However, an independent panel of experts called the U.S. Preventive Services Task Force (USPSTF) is saying that women should now start getting mammograms every other year at the age of 40, suggesting that this lowered age for breast cancer screening could save 19% more lives.

The American Cancer Society recommends getting a mammogram every other year for women 55 and older. However, women in this age group who want added reassurance can still get annual mammograms.

WATCH: When you’re getting a mammogram, ask about dense breasts.

Women with a strong family history of breast cancer, a genetic mutation known to increase the risk of breast cancer, such as a BRCA gene mutation, or a medical history, including chest radiation therapy before the age of 30, are considered at higher risk for breast cancer.

Experiencing menstruation at an early age (before 12) or having dense breasts can also put you into a high-risk category. If you are at a higher risk of developing breast cancer, you should begin screening earlier.

Screening Options for Women with Dense Breasts

Women with dense breasts should get additional screening to supplement their mammograms. Dense breasts mean more fibroglandular tissue, and less fatty breast tissue exists.

The dense tissue has a “masking effect on how well we can perceive cancer and find cancer on mammograms,” Dr. Cindy Ly, Chief of Breast Imaging and Vice Chair of Clinical Research and Faculty Affairs at the Stony Brook Renaissance School of Medicine, told SurvivorNet.

Glandular tissue within dense breasts appears white on mammograms, which can help mask potential cancer. The “frosted glass” effect from the glandular tissue can thus mask cancerous areas, especially developing ones. Undetected, these cancers can progress, growing large and advanced. They will then likely require more intensive treatments to cure, or can become incurable altogether.

WATCH: What is 3D Mammography?

“Digital mammography, it turns out, significantly improves the quality of the mammogram…It’s 3D or tomosynthesis mammography,” Dr. Connie Lehman, a diagnostic radiologist who specializes in breast cancer at Massachusetts General Hospital in Boston, explains.

“This allows us to find more cancers and to significantly reduce our false-positive rate. With digital mammography 3D tomosynthesis, we’re taking thin slices through that breast tissue, like slices of a loaf of bread. We can look at each slice independently rather than trying to see through the entire thickness of the loaf of bread. So those thin slices help us find things that were hidden in all the multiple layers,” Dr. Lehman adds.

Additional testing can be considered for dense breasts, depending on a woman’s personal history, preferences, and physician’s guidance. These tests include:

• 3-D Mammogram (Breast Tomosynthesis): This technology acquires breast imaging from multiple angles and digitally combines them into a 3D representation of the breast tissue. This allows physicians to see breast tissue architecture better, even in dense breasts. 3D mammograms are fast becoming the standard way of performing mammography.
• Breast Magnetic Resonance Imaging (MRI): An MRI machine uses magnets to create highly detailed, intricate images of the breast. These are mostly reserved for women with an extremely high breast cancer risk. Dense breasts alone may not be a valid reason to obtain a breast MRI. However, dense breasts in women with genetic mutations, like BRCA1 and BRCA2, or a strong family history of breast cancer, could justify obtaining breast MRIs.
• Molecular Breast Imaging (MBI): MBI is a newer imaging technique that uses a radioactive tracer to detect breast cancer. It is beneficial for women with dense breasts. However, MBI is not as widely available as other screening methods.

The Food and Drug Administration (FDA) requires facilities offering mammograms to notify patients about their breast tissue density and recommend that they speak with a doctor to determine if further screening is necessary. There will be “uniform guidance” on what language to use and what details to share with the patient to make the communication clear and understandable.

Understanding Your Mammogram Report

A radiologist reading mammograms categorizes breasts into four different categories using the Breast Imaging Reporting and Data System (BI-RADS), a classification system developed by the American College of Radiology (ACR). These include:

• Fatty breast tissue: These breasts are mainly fat with very little dense tissue. Found in less than 10% of women, fatty breasts appear dark on mammograms.
  Scattered fibroglandular breast tissue: These breasts contain a mix of fatty and dense tissue (composed of glands and fibrous tissue). On a mammogram, they have dark areas (fatty tissue) intermixed with light areas (dense tissue). Around 40% of women have breasts that fall in this category.
• Heterogeneously dense breast tissue: This type of breast tissue has many areas of dense tissue and some areas of fat. Found in 40% of women, these breasts look mostly light, with some dark areas on a mammogram.
• Extremely dense breast tissue: Such breasts are almost entirely composed of dense glandular and fibrous connective tissues with very little fat. They are found in 10% of women and appear light on mammograms.

Your breasts are usually called dense on a mammogram report if they fall within the heterogeneously dense breast tissue or the extremely dense breast tissue categories.

How Can I Manage Mammogram Anxiety?

It’s common to feel anxious while awaiting mammogram results. This feeling is often called mammogram anxiety.

If you are awaiting test results and your nerves are running rampant, try doing something that relaxes you, such as exercising or listening to your favorite music. Breathing exercises and meditation can also help you relax.

SurvivorNet has more resources to help you manage your mental health while awaiting test results.

Breast Cancer Symptoms & Self-Exams

Women are encouraged to do regular self-exams to become familiar with how their breasts feel normally, so when something unusual, like a lump, does form, it can be easily detected. A self-exam includes pressing your fingertips along your breast in a circular motion.

For some women, that means going to their doctor and walking through what a self-breast exam looks like, so they know what normal breast tissue feels like, so if they do feel something abnormal, whether it’s a lump or discharge from the nipple, they know what to ask and what to look for.

Below are common symptoms to look out for:

• New lump in the breast or underarm (armpit)
• Any change in the size or shape of the breast
• Swelling of all or part of the breast
• Skin dimpling or peeling
• Breast or nipple pain
• Nipple turning inward
• Redness or scaliness of the breast or nipple skin
• Nipple discharge (not associated with breastfeeding

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