JMIR Publications

ABSTRACT

Background:

Disparity in cancer burden between transgender and cisgender individuals remains an underexplored area of research.

Objective:

This study aimed to examine the cumulative incidence and associated risk factors for cancer and pre-cancerous conditions among transgender individuals compared to matched cisgender individuals.

Methods:

We conducted a retrospective cohort study using patient-level electronic health record (EHR) data from the University of Florida Health Integrated Data Repository between 2012 and 2023. Transgender individuals were identified via a validated computable phenotype algorithm using structured data and clinical notes and matched 1:10:10 by age and calendar year of index date with cisgender women and cisgender men. The index date was the first transgender-related record for transgender individuals and a matched diagnosis date for cisgender controls. Primary outcomes included new-onset cancers associated with human papillomavirus (HPV), human immunodeficiency virus (HIV), tobacco, alcohol, lung, breast, and colorectal sites. Secondary outcomes were pre-cancerous conditions related to the same cancer types. We calculated cumulative incidence rates and conducted time-to-event analyses using Fine-Gray method, treating all-cause death as a competing risk, to assess associations between gender identity and the presence of cancer or pre-cancer, adjusting for demographic and clinical covariates. Interaction analyses evaluated if associations between cancer risk factors and pre-cancer differed by gender identity.

Results:

We identified 2,745 transgender individuals (mean age at index date, 25.1 years) and matched them with 27,450 cisgender women and 27,450 cisgender men from the same healthcare system. The cumulative incidence of cancer did not differ significantly between transgender and cisgender cohorts (transgender vs cisgender women: 1.0% vs 1.3%, p=.13; transgender vs. cisgender men: 1.0% vs. 1.1%, p=.64). However, transgender individuals exhibited significantly higher risks for pre-cancerous conditions compared to cisgender women (subdistribution hazard ratios [sHR] =1.1; 95% Confidence Interval [CI]= 1.0–1.3) and cisgender men (sHR =1.3; 95% CI=1.2–1.5). Specifically, transgender individuals were more likely to develop colorectal pre-cancer (sHR =1.2; 95% CI=1.1–1.4) compared to cisgender women, as well as HPV-related pre-cancer (sHR =1.8; 95% CI=1.4–2.3) and colorectal pre-cancer (sHR =1.4; 95% CI=1.2–1.6) compared to cisgender men. Subgroup analyses showed similar patterns in both female-to-male and male-to-female individuals compared to their matched cisgender counterparts. Interaction analyses revealed stronger protective effects of private insurance or Medicare against pre-cancers in transgender individuals than cisgender peers, while being non-Hispanic Black or having substantial comorbidities were stronger risk factors among transgender individuals.

Conclusions:

Transgender individuals showed a similar cancer incidence yet significantly higher pre-cancer incidence compared to cisgender individuals, suggesting underdiagnosis or delayed detection. These findings highlight the need for tailored preventive care strategies, including targeted screenings and risk reduction interventions, to address cancer disparities in the transgender population.