Gender-affirming therapy can influence an individual’s risk of developing certain cancers, including breast cancer. A transgender person may undergo either gender-affirming hormone treatment, surgical treatment, or a combination thereof as part of their transition.
Breast cancer risk in the transgender population
A transfeminine person is usually treated with antiandrogen and estrogen hormones, whereas a transmasculine person is treated with the hormone testosterone. Gender-affirming breast surgeries can include breast reduction or mastectomy — known as “top surgery” — in transgender men, and breast enhancement with implants, fat grafting, or both in transgender women.
The same breast pathology that occurs in cisgender women can be found in transgender women treated with gender-affirming hormone therapy. As such, transgender women can have benign breast entities, such as fibroadenomas, cysts, and lipomas (fatty masses), as well as breast cancers that include ductal and lobular carcinomas.
A transgender person can present with the same breast symptoms as a cisgender person, including palpable breast masses (lumps) and breast pain as well as normal or abnormal nipple discharge.
Navigating breast health for transgender people
The incidence of breast cancer in the transgender community is largely unknown because of inadequate epidemiological information and a lack of long-term studies. A younger age at the time of breast cancer
diagnosis has been reported in transgender people.
Identifying transgender patients
A transfeminine person identifies with the female side of the gender spectrum but was assigned male at birth. These individuals may include transgender women, historically referred to as male-to-female transsexuals.
A transmasculine person identifies with the male side of the gender spectrum but was assigned female at birth. These individuals may include transgender men, historically referred to as female-to-male transsexuals.
For transgender and gender-nonconforming individuals, breast cancer screening recommendations are based on the sex assigned at birth, risk factors, and use of exogenous hormones.
A cisgender person has a gender identity that matches the sex assigned at birth.
Transgender breast cancer signs and symptoms
Some of the things you could be experiencing are:
- A painless lump or thickening in your breast tissue
- Changes to the skin covering your breast, such as dimpling, puckering, redness or scaling
- Changes to your nipple, such as redness or scaling, or a nipple that begins to turn inward
- Discharge from your nipple
Screening guidelines
There is no consensus on screening guidelines in transgender patients. The guidelines presented here are a summary from the American College of Radiology, using available studies and recommendations primarily from UCLA, Fenway Health, and the Endocrine Society, as well as a Dutch study including 3,489 transgender patients.
Imaging guidelines for transgender women
Recommendations for breast cancer screening in a transfeminine person is typically based on:
- The male sex assigned at birth
- The number of years of feminizing hormone exposure
- Breast development
- Any significant risk factors for breast cancer
Listed below are common scenarios for transgender women with corresponding breast cancer screening guidelines based on the above factors:
A transfeminine (male-to-female) person, 40 years of age or older with past or current hormone use equal to or greater than five years who is at average risk.
- No long-term data exists for screening transgender women for breast cancer with imaging.
- A Dutch cohort study of 3,489 transgender patients showed an increased risk of breast cancer in transgender women receiving gender-affirming hormone therapy compared with cisgender men but not compared with cisgender women.
- Large prospective cisgender studies have shown that taking hormones, in particular estrogen and progestin, increase breast cancer risk in cisgender postmenopausal females, which could support a role for screening in this clinical setting. Additionally, in cisgender males, high estrogen levels associated with certain conditions, such as Klinefelter syndrome, liver disease, testicular dysfunction, and obesity, are recognized risk factors for developing breast cancer.
- Current breast cancer screening recommendations in transgender women, 40 years or older with past or current hormone use equivalent or greater than five years, have two options:
- Annual or biennial mammograms starting at age 50 (per UCSF and Fenway Health recommendations)
- Screening transgender women with the same frequency as cisgender women (annually) beginning at age 40 (per the Endocrine Society).
A transfeminine (male-to-female) person, 25 to 30 years of age or older with past or current hormone use equal to or greater than five years who are higher-than-average risk (this includes individuals with a personal history of breast cancer or chest irradiation at 10 to 30 years of age, those with a genetic predisposition to breast cancer, those with a family history of breast or ovarian cancer, and an untested individual with first-degree relative with genetic predisposition to breast cancer).
- Limited data on transgender individuals, along with extrapolated data from cisgender studies, suggest that digital mammography or DBT is helpful to screen for breast cancer in higher-than-average-risk transgender women.
- Some transgender health experts and professional societies recommend digital mammography or tomosynthesis to screen for breast cancer in transgender women with higher-than-average risk of breast cancer. Learn more.
- There is no consensus on the age at which to initiate screening in this clinical setting.
- The Endocrine Society recommends screening transgender women with the same frequency as cisgender women (annually beginning at age 40).
- The ACR screening recommendation for high-risk cisgender women is annual screening mammography beginning 10 years earlier than an affected relative at the age of diagnosis (but not before age 30) or 8 years after radiation therapy (but not before age 25)
A transfeminine (male-to-female) person with no hormone use (or hormone use less than five years) at any age who is at average risk.
- There is no literature to support the use of digital mammography for breast cancer screening in this clinical setting.
- In the absence of identifiable risk factors for breast cancer, general screening has no role because of an overall low prevalence of disease. The lifetime risk of breast cancer in a transfeminine person with no hormone use and no significant risk factors is considered to be equivalent to the average risk in cisgender men, which is 0.1% (compared with 12.4% in the average-risk cisgender female).
A transfeminine (male-to-female) person, 25 to 30 years of age or older with no hormone use (or hormone use less than five years) who is at higher-than-average risk (personal history of breast cancer or chest irradiation at 10 to 30 years of age, person with genetic predisposition to breast cancer, having a family history of breast or ovarian cancer, and having a first-degree relative with genetic predisposition to breast cancer, but being untested yourself).
- Limited data from risk-comparable cisgender men suggest that screening mammography or tomosynthesis may be beneficial in this clinical setting.
Imaging guidelines for transgender men
Recommendations for breast cancer screening in a transfeminine person are typically based on:
- The male sex assigned at birth
- The number of years of feminizing hormone exposure
- Breast development
- Any significant risk factors for breast cancer
Below are common scenarios for transgender women with corresponding breast cancer screening guidelines based on the above factors:
A transmasculine (female-to-male) person with bilateral mastectomies (“top surgery”) at any age and any risk.
- Estimation of breast cancer risk reduction in transmasculine patients following simple mastectomy is derived from high-risk cisgender women. A <2% risk of breast cancer is observed in cisgender women who undergo prophylactic mastectomy due to inherited cancer predisposition. Hence, it is conjectured that transgender men are at a comparably very low risk of developing breast cancer after top surgery.
- There is no relevant literature to support the use of digital mammography tomosynthesis for breast cancer screening in this clinical setting.
A transmasculine (female-to-male) person with breast reduction surgery or no chest surgery, 40 years of age or older who are at average-risk.
- A transmasculine person who has not undergone top surgery (and has breast tissue) has a breast cancer risk comparable with cisgender women irrespective of hormone treatment.
- Annual screening with digital mammography or tomosynthesis is recommended in this clinical setting to screen for breast cancer beginning at age 40 and continuing while life expectancy exceeds 5 to 7 years because transmasculine patients without top surgery have breast cancer risk similar to cisgender women.
A transmasculine (female-to-male) person with breast reduction or no chest surgery, 30 years of age or older who is at intermediate risk (has a personal history of breast cancer, lobular neoplasia, atypical ductal hyperplasia, or 15% to 20% lifetime risk of breast cancer).
- A transmasculine person who has not undergone top surgery (and has breast tissue) has a breast cancer risk comparable with cisgender women irrespective of hormone treatment.
- Transmasculine individuals with an intermediate risk of breast cancer may benefit from beginning screening mammography earlier than 40 years of age and may also benefit from supplemental screening.
- Annual screening with digital mammography or DBT is recommended in this clinical setting as it is for risk-comparable cisgender women with high-risk lesions, such as lobular neoplasia or atypical ductal hyperplasia, beginning at diagnosis but not before 30 years of age.
- Transmasculine individuals with a personal history of breast cancer are recommended to have mammography every 12 months because their breast cancer risk is similar to cisgender women.
- Screening with breast MRI or bilateral complete ultrasound may be indicated to supplement mammography in this population.
A transmasculine (female-to-male) person with breast reduction or no chest surgery, 30 years of age or older who is at intermediate risk (has a personal history of breast cancer, lobular neoplasia, atypical ductal hyperplasia, or 15% to 20% lifetime risk of breast cancer).
- In addition to beginning screening earlier than average-risk cisgender women, people in this high-risk group benefit from supplemental screening.
- Annual screening with digital mammography or tomosynthesis is recommended in this clinical setting beginning eight years after radiation therapy but not before age 25 for patients who received mantle radiation between 10 and 30 years of age.
- In transmasculine individuals with familial breast cancer risk, an annual screening mammogram is recommended starting 10 years earlier than the affected relative’s age at diagnosis but not before 30 years of age, as their breast cancer risk is similar to cisgender women.
- Supplemental screening with breast MRI is appropriate in this population, in addition to annual screening mammography.
- Supplemental screening with breast ultrasound may be appropriate in this population.