The prostate remains after gender-affirming surgery, so prostate cancer risk does not disappear. Yet the incidence in transgender women has been poorly understood—and this large analysis finds lower risk, but not zero risk. After transgender women undergo genital gender-affirming surgery, the prostate remains in situ, conferring an ongoing risk for prostate cancer.

However, the incidence of prostate cancer in this population is relatively unknown, and current evidence-based guidelines for prostate cancer screening in transgender women are limited by this minimal data. Some studies report between a two- to fivefold decrease in prostate cancer risk compared with cisgender men.

This study investigates rates of prostate cancer after medical or surgical transition to better inform screening guidelines. The study used the TriNetX database, with deidentified electronic health records for one hundred twenty million patients and over forty thousand transgender women from the United States.

This was a retrospective cohort study comparing prostate cancer rates among transgender women, identified using ICD-10 code F64. Three cohorts were created: no medical or surgical intervention, estrogen hormone therapy without surgery, and hormone replacement therapy with gender-affirming surgery defined specifically by orchiectomy.

Patients with prostate cancer before their index event were excluded, as were people with orchiectomy before hormone therapy to reduce inclusion of orchiectomies performed for other reasons. The comparison used a standardized incidence ratio, or SIR, to assess prostate cancer incidence among transgender women against the general population.

Expected cases came from National Institutes of Health Surveillance, Epidemiology, and End Results data using five-year age-adjusted incidence rates from 2016 through 2020. The SIR was calculated by comparing observed cases from TriNetX with expected cases determined from the NIH SEER data.

The cohort included forty thousand seven hundred twenty-seven transgender women, with forty-three prostate cancer cases observed during an average three-year follow-up. Among transgender women aged fifty to sixty-four receiving hormone therapy, prostate cancer risk was zero point four eight compared with SEER data; across all ages receiving hormone therapy, the risk was zero point two two.

The hormone therapy group had received hormone therapy for an average of two years before prostate cancer diagnosis. Table one reports prostate cancer standardized incidence ratios by age and intervention cohort among trans women, comparing observed cases with expected cases based on US incidence rates.

Overall, the ratio was zero point two two for the hormone-therapy cohort and zero point three nine for all trans women, both marked significant, while age-specific estimates have wider confidence intervals. The table matters because it quantifies the reduced incidence described by the authors and shows how estimates vary across age and treatment groups.

In the no-intervention group, prostate cancer risk compared with cisgender men was zero point six two. However, after age stratification, prostate cancer risk was not significant across all age groups. Among transgender women who received both hormone therapy and surgery, only one prostate cancer case was observed, in a patient thirty-eight years of age.

Among those diagnosed with prostate cancer, the median PSA among the hormone therapy group at diagnosis was seventeen point one eight. Table two summarizes forty-three transgender women diagnosed with prostate cancer, grouped by no intervention, hormone therapy, and hormone therapy plus surgical intervention.

It reports median PSA, age at diagnosis, and time from the index event to diagnosis, with the hormone-therapy group showing a median of two years and a range below one to six years. These details matter because the authors connect them to interpreting PSA and understanding prostate-cancer detection among transgender women receiving hormone therapy.

The study represents the largest cohort of transgender women examined for prostate cancer to date. It found a twofold lower incidence among transgender women aged fifty to sixty-four receiving hormone therapy. Considering transgender women of all ages, the study identified a two point five six-fold lower incidence of prostate cancer.

The lower incidence may be partly attributed to the overall younger age of the transgender women population. Even after age stratification and accounting for follow-up time, however, the study observed a twofold lower incidence among hormone therapy recipients aged fifty to sixty-four.

Large electronic medical record database studies have limitations, including potential issues with the completeness and accuracy of medical records. The study reports a twofold decrease in prostate cancer incidence among transgender women receiving hormone therapy between fifty and sixty-four years old.

Contrary to previous assumptions, prostate cancer may not be as exceedingly rare among transgender women as once believed. Rates remain decreased relative to cisgender men, but occurrences are not infrequent, so healthcare providers should consider prostate cancer when managing the health of transgender women.

The study finds lower prostate cancer incidence among transgender women, especially those aged 50 to 64 receiving hormone therapy, while emphasizing that prostate cancer still occurs and should remain part of appropriate care.