Pathological Evaluation of Breast Specimens in Transgender Chest Masculinization: Incidental Findings and Effect of Prior Chest Binding and Androgen Therapy in 74 Consecutive Patients

Background: The rate of masculinizing chest surgery for gender affirmation continues to increase. With a paucity of literature on pathological evaluation of breast specimens in this patient population, there is a need for these data and for protocols on the handling of these specimens. Methods: A retrospective chart review was performed between 2015 and 2020 on all patients who underwent chest masculinization surgery for gender dysphoria by the senior author (J.D.K.). Inclusion criteria were any patient with sex assigned female at birth who underwent removal of breast and/or nipple areolar complex tissue for gender affirmation. Patient demographics were recorded. Bilateral breast tissue was sent for routine pathology in all cases and findings were recorded. A p-value of <0.05 was considered significant. Results: Seventy-four consecutive patients and 148 breast specimen reports were identified from a database and included in the study. The mean age was 26 years (15-49). Thirty-nine patients had a known history of chest wall binding and 60 patients had undergone preoperative androgen therapy. There was no invasive or in situ carcinoma found in any breast tissue specimens. Thirty-four patients had a benign lesion in one or both breast specimens. Atypical lobular hyperplasia was found in one patient's specimen. A history of chest wall binding was not correlated with any benign lesions (p=0.79) or stromal fibrosis (p=0.94). A history of testosterone use was not correlated with any benign lesions (p=0.35) or stromal fibrosis (p=0.20). Conclusions: The prevalence (1.4%) of significant breast pathology and of benign findings (46%) in our study closely correlates with the rates in the literature. We found no correlation between significant breast pathology or benign lesions and a history of chest wall binding or preoperative androgen therapy. We recommend all breast specimens removed during chest masculinization surgery be sent for pathological evaluation.