Breast Cancer in Transgender Patients Following Medical and Surgical Intervention

Area of Science:

• Oncology
• Endocrinology
• Health Disparities

Background:

• Current breast cancer screening guidelines lack specific recommendations for transgender populations.
• Transgender individuals have unique considerations regarding hormone exposure and post-surgical anatomy impacting cancer risk.

Purpose of the Study:

• To investigate breast cancer incidence and risk factors in transgender women and men.
• To evaluate the impact of hormone therapy and chest surgery on breast cancer risk in transgender individuals.

Main Methods:

• Utilized the TriNetX network (2003-2023) to identify transgender adults using ICD-10 codes.
• Grouped individuals by sex assigned at birth and intervention: no intervention, hormone therapy (≥ 1 year), or hormone therapy with surgery.
• Defined breast cancer as ≥ 2 malignant breast neoplasm diagnoses (ICD-10 C50.x).

Main Results:

• Among 33,775 transgender women, 12 (0.036%) developed breast cancer; hormone therapy alone was not associated with increased risk.
• Among 44,117 transgender men, 37 (0.084%) developed breast cancer.
• Combined hormone therapy and chest surgery were associated with higher breast cancer odds in transgender men compared to no intervention. Older age and Black race were significant predictors in both groups.

Conclusions:

• Hormone therapy alone does not elevate breast cancer risk in transgender individuals.
• Residual breast tissue post-surgery may contribute to ongoing breast cancer risk in transgender men.
• Individualized screening strategies considering intervention type, age, and race are recommended for transgender populations.