Importance: Evidence on prostate cancer (PCa) in transgender women is very limited; data are needed to reduce gender disparities in both PCa knowledge and health care.
Objective: To evaluate the prevalence of PCa among transgender women in the US and assess the factors associated with PCa, and factors associated with biochemical recurrence (BCR) and bone metastases (BM) secondary to PCa in the transgender population.
Design, setting, and participants: A retrospective cohort study was conducted in October 2023, covering the period between 2011 and 2022 (12-year analysis). The study was based on a large, all-payer claims, deidentified, US database (PearlDiver Mariner). Transgender women who were identified as male before assignment of transsexual status codes were included. Patients with PCa were detected in the transgender women population.
Main outcomes and measures: PCa diagnosis was selected as primary outcome; BCR and BM were chosen as secondary outcomes.
Results: A total of 95 460 transgender women with a mean (SD) age of 52.5 (9.4) years were included. PCa was diagnosed in 589 individuals with a mean (SD) age of 66.8 (10.0) years (estimated prevalence, 0.62%; 95% CI, 0.54%-0.77%). Age (adjusted odds ratio [OR], 1.10; 95% CI, 1.08-1.12; P < .001) and family history (adjusted OR, 2.27; 95% CI, 1.60-4.92; P < .001) were positively associated with PCa in transgender women. Gender-affirming hormone therapy (GAHT) was negatively associated with PCa in transgender women (OR, 0.60; 95% CI, 0.56-0.89; P < .001) but positively associated with BCR (OR, 1.83; 95% CI, 1.21-2.86; P < .001) and BM (OR, 3.96; 95% CI, 1.50-9.99; P < .001) in the transgender population with PCa.
Conclusions and relevance: This cohort study found that PCa appeared to be relatively uncommon in transgender women. GAHT may reduce the risk of PCa in transgender patients, but it may also increase the risk of BCR and BM in transgender women with PCa. Further studies are needed to confirm our findings.