8425 Cancer Risk in Transgender Veterans Undergoing Gender-Affirming Hormone Therapy in a Single Medical Center

Abstract Disclosure: A. Vanasco: None. A. Chitnavis: None. K.L. Vinales: None. R.R. Correa: None. Background: The risk of cancer in the transgender patients while on Gender Affirming Therapy is still a source of safety concern among healthcare professionals. We aimed to assess the cancer incidence and potential risk factors in this population. Methods: An initial cohort of 428 charts within the Phoenix VA Healthcare System from January 1990 through October 2023 were identified using ICD codes consistent with a diagnosis of gender dysphoria. From this initial cohort, we completed a chart review of 94 patients who received GAHT through the endocrinology department. The collected information included type of cancer diagnosis, self-reported GAHT start date if not at the Phoenix VA, and risk factors for cancer (HPV, HIV, smoking history) along with recommended cancer screening, like latest mammogram, pap smear, and colonoscopy. Results: We identified 67 transgender women and 27 transgender men, 53.8± 16.0 and 43.8 years ± 12.6 years-old, with an average of 10 years of GAHT (10.1±7.4 years for estradiol therapy and 10.2±4.4 years for testosterone therapy, range 0.5-44 years of use). Cancer was diagnosed in 18 (27.7%) transgender women, including 8 skin, 3 lung, 2 prostate, 2 tongue, 1 thyroid, 1 musculoskeletal, 1 sinus, 1 bladder cancer. Among our transgender women, 37% were current and 33% were prior smokers. Two (3.0%) were HPV positive and both had cancer diagnoses, while two (3.0%) were HIV positive and neither had a cancer diagnosis. 19 (28.4%) underwent colonoscopies with benign results and 48 (71.6%) were untested. 21 (31.3%) underwent mammograms with benign findings, 1 (1.5%) had a mastectomy and reconstruction, and 45 (67.2%) were untested. Cancer was diagnosed in 3 (10.3%) transgender men, and included 2 skin, 1 breast, 1 cervical cancer. 4 (14.8%) were HPV positive, none of which had cancer. Forty percent of the transgender men were active smokers and an additional 30% were prior smokers. None were HIV positive. 8 (29.6%) underwent colonoscopy, 7 of which were benign and 1 pending results, and 19 (70.1%) were untested. Three (11.1%) underwent mammograms with benign findings, 16 (59.3%) had bilateral mastectomies, and 8 (29.6%) were untested. Eleven (40.7%) had pap smears with 10 benign findings and 1 ASCUS, 11 (40.7%) had hysterectomies, and 5 (18.5%) were untested. Conclusion: Our study sheds light on cancer incidence in transgender veterans undergoing GAHT. Incidence of cancer was higher in transgender women than transgender men, and the leading type of cancer for both groups was of the skin, not considered a GAHT risk. Significant numbers of both transgender men and women did not receive recommended health screenings, highlighting the need for improved education of screening importance. Presentation: 6/2/2024