Clinical characteristics of transgender patients with breast cancer: a single institution experience.

Breast cancer presents unique complexities for transgender individuals. This retrospective study characterized breast cancers in 14 transgender and nonbinary patients treated at a specialized transgender health center from 2016 to 2023. Patients with a median age of 53 (31-65 years) were identified using international classification of disease-10 codes. Most (86%) were aged 40 or older and eligible for screening mammography. The cohort included 6 trans men, 7 trans women, and one genderqueer individual. Diagnoses included ductal carcinoma in situ (36%), lobular carcinoma in situ (7%), stage 1 (29%), stage 2 (21%), and breast implant-associated anaplastic large cell lymphoma (7%). Screening mammography diagnosed 29%, 43% presented with a mass, and 29% were detected during pre-surgical imaging. Half had estrogen-based gender-affirming hormone therapy (GAHT) and half testosterone-based, with mean GAHT durations of 16.6 years. Biomarker profiles revealed 67% estrogen receptor (ER)-positive and 33% ER-negative cancers. This study highlights underutilized screening mammography and diverse cancer subtypes in this underserved population.