Context.—: Transgender men and transmasculine persons experience a discordance between the female sex they were assigned at birth and their gender. They may choose to take hormone therapy and/or undergo surgery to masculinize the body. Understanding the common (and less common) histologic changes present in patients taking masculinizing hormones will empower pathologists to better serve this unique patient population.
Objective.—: To summarize histologic findings in surgical pathology specimens from persons taking masculinizing hormones as a part of gender transition.
Data sources.—: A systematic review of the OVID Medline and PubMed databases was performed to identify all studies describing histologic findings in surgical pathology specimens from transgender men from January 1946 to January 2021.
Conclusions.—: Publication in this area has markedly increased in the last 2 decades. However, most of the studies identified were descriptive and case reports describing changes seen in specimens removed as a part of masculinizing surgical procedures. Benign histologic findings include stromal hyalinization and epithelial atrophy in the breast, polycystic ovarian syndrome-like changes in the ovary, and transitional cell metaplasia in the cervix. The most commonly reported neoplastic finding was adenocarcinoma of the breast, with rare cases of ovarian, endometrial, cervical, vaginal, pituitary, pancreatic, and cardiovascular neoplasia also reported. Ongoing research in this area is needed to better characterize the histologic findings in persons taking masculinizing hormones to provide a deeper understanding of the effect of these treatments on different tissues and facilitate better patient management.