At what age should a transgender female on estradiol (estrogen replacement therapy) for over 10 years with unknown family history start breast cancer screening?

From the Guidelines

Transgender women on estradiol therapy for over 10 years should begin breast cancer screening at age 40, following the same guidelines as cisgender women with average risk, as the benefits of early detection outweigh the risks of screening. This recommendation applies when family history is unknown. The screening should consist of mammograms every 1-2 years. If the transgender woman began hormone therapy after age 40, screening should start after 10 years of continuous estrogen exposure. The ACR recommends annual screening mammography beginning no later than 40 years of age for women at intermediate risk 1. For women 40 to 49 years of age, randomized controlled trials and observational studies demonstrate that screening mammography decreases breast cancer mortality by 15% to 50% 1. Annual screening mammography results in a greater reduction in mortality compared to biennial screening 1. Given the limitations of mammography and to minimize interval cancers, supplemental screening modalities have been investigated in women at high risk, but screening mammography or screening DBT is still performed in women undergoing supplemental screening studies 1. If any breast abnormalities such as lumps, pain, or nipple discharge occur before the recommended screening age, immediate medical evaluation is warranted regardless of age or duration of hormone therapy. Some key points to consider:

• The degree of breast cancer mortality reduction from screening mammography varies with different screening regimens, with greater reduction when screening begins at 40 years of age rather than 45 or 50 years of age and when screening is done more frequently (annually rather than biennially) 1.
• Women should continue screening mammography as long as they remain in overall good health and are willing to undergo the examination and subsequent testing or biopsy, if an abnormality is identified 1.
• Overdiagnosis estimates increase with age at screening, but the benefits of screening outweigh the risks 1.
• The sensitivity of mammography is decreased in some groups of women, including those with dense breasts, but screening mammography is still the most effective method for reducing breast cancer mortality 1.

From the Research

Breast Cancer Screening for Transgender Females on Estradiol

• The optimal age for a transgender female patient on estradiol for more than 10 years to start breast cancer screening is not explicitly stated in the provided studies 2, 3, 4, 5, 6.
• However, study 4 suggests that long-term postmenopausal estrogen therapy may be associated with an increased risk of breast cancer, which could be relevant for transgender females on long-term estradiol therapy.
• The study 4 found that women who took estrogen for an average of 17.2 years had a significantly increased risk of breast cancer compared to non-users.
• It is essential to consider the individual's risk factors, such as age, family history, and duration of estradiol use, when determining the appropriate age to start breast cancer screening.
• Studies 3, 5, and 6 discuss the importance of breast self-examination, clinical breast examination, and breast awareness in early detection of breast cancer, but do not provide specific guidance on screening age for transgender females on estradiol.
• In the absence of specific guidelines, healthcare providers may consider recommending breast cancer screening for transgender females on estradiol based on individual risk factors and in accordance with general guidelines for breast cancer screening in cisgender women 2.