Breast cancer and transgender people

The American Cancer Society estimates that 310,720 new cases of invasive breast cancer (breast cancer that can spread to surrounding tissue) will be diagnosed in women in 2024. Except for skin cancers, breast cancer is the most common cancer in women, or people who are assigned female at birth (AFAB), in the United States. More than 40,000 breast cancer deaths are expected to occur in 2024.

A person AFAB is much more likely to develop breast cancer than a person assigned male at birth (AMAB), regardless of gender identity. Much of what is known about breast cancer, its treatments, care, and outcomes does not take a person’s gender identity into account.

We know that in addition to being AFAB, risk factors for breast cancer include age, personal history of breast cancer, family history of breast cancer, having certain genetic mutations, and being of Ashkenazi Jewish descent. (You can learn more about risk factors on the What is breast cancer? page.)

We don’t know how many people who identify as transgender are living with breast cancer. One of the reasons for this is that historically, cancer registries haven’t collected this information. However, this is changing: National organizations such as the American Society of Clinical Oncology (ASCO) and the American Association of Cancer Research (AACR) have been advocating to collect this data.

What we know about transgender people and breast cancer risk, screening, and diagnosis

• Information about the risk of breast cancer for transgender people is limited, but:
  • The risk for transgender people AMAB is much higher than for cisgender men.
  • The risk for transgender people AFAB is much lower than for cisgender women.
• Transgender individuals are significantly less likely to be screened for breast and cervical cancer compared with cisgender individuals. (American Journal of Clinical Oncology, 2022)
• Transgender people are more likely to be diagnosed at a younger age than cisgender women.
• Research suggests that transfeminine people (people AMAB who identify more as feminine than masculine) using hormone treatments have an increased risk for breast cancer compared with cisgender men.
• In 2021, the American College of Radiology (ACR) published breast cancer screening guidelines for transgender people based on sex (male or female) assigned at birth, risk factors, and use of hormone therapy or surgery that may be used in the transitioning process.

Transgender health statistics and disparities

The lack of statistics is both a cause and an effect of health disparities that exist for transgender people, as well as for members of other sexual and gender minority groups.

Health disparities are health differences that are closely linked to being part of disadvantaged populations, or groups of people, who have experienced greater obstacles to health due to such things as ethnicity or religion, socioeconomic status, disability, gender, or sexual orientation or gender identity (SOGI).

Lack of information and access affect cancer care and research for many of these groups. For example, we know that transgender people are less likely to get screened for breast cancer. Delays in screening can lead to delays in a breast cancer diagnosis—and being diagnosed at a later stage when the outcome may not be the same as it might be if diagnosed earlier. In addition to screening delays, not being aware of common symptoms of breast cancer can cause delays in diagnosis.

Transgender people and other people in SOGI minority groups may avoid seeking health care for several reasons, including:

• Refusal of care; one out of five transgender patients has been turned away when seeking health care
• Past experiences of discrimination in a healthcare setting
• Past experiences of transphobia
• Lack of health insurance; of all LGBTQ+ groups, transgender individuals have the lowest rates

Gathering accurate statistics can also be a challenge. LGBTQ+ individuals may not always feel comfortable disclosing their SOGI to their healthcare teams, and healthcare providers may not always ask about it.

Without that information, researchers can’t collect some of the data that leads to studies specific to the LGBTQ+ community, as well as data on subgroups within the LGBTQ+ community (for example, lesbian-specific or transfeminine-specific research and studies).

Still, there is good news. “Things are changing in a positive direction,” says Elizabeth Cathcart-Rake, MD, assistant professor of oncology at the Mayo Clinic. Dr. Cathcart-Rake’s research focuses on screening mammography for transgender and gender-diverse people. “There are a lot of clinicians who really, really care, and people who are working to change things.”

Finding trans-friendly care

When seeking care, you may want to call a doctor’s office or screening or treatment center to ask if they have experience caring for transgender people. You don’t need to give your name when you call. You can also ask LGBTQ+ friends who have been treated for breast cancer or other types of cancer for recommendations on healthcare centers that they have found to be welcoming. The National LGBT Cancer Network also offers a provider database.

If you feel uncomfortable with how you are treated by a doctor or any member of a healthcare team, it’s important to seek emotional and mental health support, legal resources such as Lambda Legal, or both.

Talking with your healthcare team

If you identify as transgender, many factors may impact whether you’re comfortable talking with your doctors about your gender identity. Whether to talk openly with them is a personal choice.

If your doctor asks about your SOGI, you are not obligated to share that information with them. Keep in mind, though, that being open and honest about your breasts, your body, possible risk factors for breast cancer, and hormones you may take can help your doctors provide more complete care for you. The more your doctors know about you, the more they can help you with care decisions.

You may want to bring a loved one or friend to an appointment for support. Consider sharing your pronouns as a way to share your gender identity and begin an open conversation with your care team.

Hormones, transgender hormone therapy, and breast cancer

We know that some forms of hormone replacement therapy (HRT), a treatment given to postmenopausal cisgender women experiencing unwanted menopausal symptoms, can increase the risk of developing breast cancer. HRT that contains estrogen is not safe for people diagnosed with estrogen receptor-positive breast cancer, for example.

Early research suggests a relationship between gender-affirming hormone therapy and breast cancer risk in transgender people compared to risk based only on sex assigned at birth.

Any time breast cancer is diagnosed, tests are performed on the cancer so doctors can understand whether the cancer is growing because of estrogen or other hormones in the body. This information may be especially significant for people who are taking hormones as part of their gender transition.

Estrogen, or feminizing, therapy

Taking estrogen helps with growth of secondary female sex characteristics, such as breast development. Transfeminine people who wish to develop these sex characteristics and decrease their levels of testosterone may decide to take estrogen. But taking estrogen may promote cancer cell growth in people who have been diagnosed with hormone receptor-positive breast cancer.

If a person is taking estrogen as part of their transition and is diagnosed with hormone receptor-positive breast cancer, doctors will discuss the risks and benefits of stopping estrogen-based hormone therapy.

Testosterone, or masculinizing, therapy

There is no conclusive evidence to show a relationship between testosterone therapy, for female to male transitioning, and breast cancer.

Research is early and inconclusive on how testosterone supplementation impacts people diagnosed with breast cancer. If you take testosterone and have been diagnosed with breast cancer, talk with your doctor about your individual risk of breast cancer and recurrence, and how testosterone therapy may affect it.

Deciding whether to continue transgender hormone therapy after a breast cancer diagnosis

If you are taking gender transitioning hormone therapy and are diagnosed with breast cancer, your doctor may recommend that hormone therapy be stopped completely. It can be traumatic to hear this news. It may feel unfair to have to choose between cancer treatment and hormones for gender affirmation. Doing what feels right for your identity can feel just as critical as treating the cancer. Talk with your doctor about how continuing to take hormone therapy might impact your diagnosis, treatment, and risk of recurrence. For extra support, talking with a therapist can be helpful in making the right decision for you.

“It’s always a risk/benefit discussion,” says Dr. Cathcart-Rake. “Gender-affirming hormone therapy is often life-saving; it’s at the core of identity.”

“It’s a really difficult situation,” she continues. If a patient is diagnosed with hormone receptor-positive breast cancer, she says, “I will talk about the risks. Oftentimes, I’ll talk about a lot of unknown risks, unfortunately, if I think the hormones the person is taking contribute to breast cancer proliferation.”

If you are transgender and have been diagnosed with hormone receptor-positive breast cancer, it’s likely that anti-estrogen therapy will be recommended to treat the cancer. Examples of anti-estrogen treatments include:

• Endocrine therapy, such as tamoxifen or aromatase inhibitors
• Ovarian suppression medicines
• Oophorectomy, or removal of the ovaries in people who have ovaries

In most people, anti-estrogen therapies cause menopausal symptoms and other side effects related to hormones in the body. It is not clear whether these side effects would be different if you are transitioning.

Finding support

A breast cancer diagnosis is devastating for anyone. No two people living with breast cancer experience the disease in the same way. In addition, no two people who identify as transgender have the same life experience or transitioning experience. If you identify as transgender or gender-diverse, however, it’s likely that your gender identity, and the health disparities associated with being a member of the LGBTQ+ community, will present you with unique challenges and decisions.

Whether you identify as female or male, transgender or cisgender, lesbian, gay, bisexual, queer/questioning, or straight, no one should face cancer alone. Mental health professionals who are familiar with transgender issues can guide you through treatment and beyond. When choosing a therapist, consider whether they have experience with:

• LGBTQ+ issues, specifically in the transgender community
• Cancer or other life-threatening diseases
• A transgender individual potentially being advised to stop gender-transitioning hormone therapy because of a cancer diagnosis

For additional support, the National Center for Transgender Equality offers resources related to health care, transgender-related laws and rights, and mental health resources.