The effects of gender affirming hormone therapy on prostate specific antigen (PSA) and prostate cancer incidence in transgender or non-binary individuals (TGNB) born with prostate glands remains uncharacterized.
The cohort included 1,024 self-identified TGNB individuals assigned male at birth who received PSA testing in the VA Healthcare System, matched by birth year to cisgender men. PSA changes were measuring using linear-mixed effects modeling accounting for repeated measured and matching.
Non-gonadotrophin releasing hormone agonist or antagonist (GnRH) therapy was associated with 1.30 ng/mL lower PSA (95% confidence interval (CI) 1.14-1.46, p < 0.001) and GnRH therapy was associated with 1.08 ng/mL lower PSA (95% CI 0.60-1.55, p < 0.001) compared with cisgender men. Among 450 TGNB individuals who had PSA testing before and after initiation of hormone therapy, non-GnRH and GnRH therapies resulted in 0.49 ng/mL decrease (95% CI 0.35-0.62, p<0.001) and 0.73 ng/mL decrease (95% CI 0.43-1.02, p<0.001), respectively, from median baseline of 0.70 ng/mL. From time of age 50, TGNB prostate cancer incidence was 1.79 per 1,000 patient-years versus 4.02 per 1,000 patient-years in cisgender men.
Gender affirming hormone therapies are associated with significant decreases in PSA, and TGNB individuals assigned male at birth remain at risk for prostate cancer. Future work should establish if a lower threshold for biopsy should be used in these contexts and if the decreased incidence is a result of ascertainment bias or hormone therapy resulting in a true decrease in the incidence of prostate cancer.
International journal of radiation oncology, biology, physics. 2024 Sep 25 [Epub ahead of print]
Kylie M Morgan, Leah N Deshler, Michelle D Tibbs, Edmund M Qiao, Jennifer T Anger, Amirali Salmasi, Deborah C Marshall, Parag Sanghvi, Brent S Rose, Paul Riviere
University of California San Diego, Department of Radiation Medicine and Applied Sciences, La Jolla, CA; University of California San Diego, Center for Health Equity and Education Research (CHEER), La Jolla, CA; Veterans Affairs San Diego, La Jolla, CA., University of California San Diego, Department of Urology, La Jolla, CA., Icahn School of Medicine, Department of Radiation Oncology, Department of Population Health Science & Policy, New York, NY., University of California San Diego, Department of Radiation Medicine and Applied Sciences, La Jolla, CA., University of California San Diego, Department of Radiation Medicine and Applied Sciences, La Jolla, CA; University of California San Diego, Center for Health Equity and Education Research (CHEER), La Jolla, CA; Veterans Affairs San Diego, La Jolla, CA. Electronic address: .