Abstract
IMPORTANCE: Persistent chemotherapy-induced alopecia (PCIA) is a distressing adverse effect that can have lasting psychosocial consequences. However, racial and ethnic differences in PCIA incidence and associated distress remain unclear, owing to limited multiracial and multiethnic data. OBJECTIVE: To evaluate racial and ethnic disparities in the incidence of PCIA and alopecia-related psychological distress among women with breast cancer from baseline to 12 months after completion of chemotherapy. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study was conducted at 2 tertiary cancer centers in the US (August 19, 2015, to December 31, 2021) and South Korea (December 20, 2018, to April 27, 2022). Women (aged ≥18 years) with stage I to III breast cancer who received chemotherapy were included. Data analysis was conducted from June 30 to July 15, 2025. EXPOSURES: Standardized trichoscopic assessments were performed and validated distress questionnaires were administered at baseline and 12 months after treatment. MAIN OUTCOMES AND MEASURES: The primary outcome was PCIA incidence, which was defined as hair thickness or density at 12 months after completion of chemotherapy that fell more than 2 SDs below the level measured before chemotherapy. Secondary outcomes included changes in hair density, hair shaft thickness, and alopecia-related distress, measured using the Chemotherapy-Induced Alopecia Distress Scale (CADS). RESULTS: The 304 women (mean [SD] age, 50.3 [10.6] years) in this study were Asian (n = 159 [52.3%]), Black (n = 20 [6.6%]), Hispanic or Latino (n = 17 [5.6%]), or White (n = 108 [35.5%]). At baseline, Asian women had the thickest hair shafts (mean [SD], 83.2 [13.4] µm) but the lowest follicular density (mean [SD], 136.2 [27.6] hairs/34.34 mm2 at ×50 magnification; P < .001). At 12 months, PCIA incidence was highest in Asian women (59 [42.1%]), followed by White (24 [22.2%]), Black (2 [10.0%]), and Hispanic or Latino (1 [5.1%]) women (P = .001). Asian women also had the greatest increase in CADS scores compared with White women, particularly in the emotional (adjusted mean difference, 1.88 [95% CI, 0.92-2.95]) and activity-related (1.55 [95% CI, 0.58-2.52]) domains. CONCLUSIONS AND RELEVANCE: In this prospective multinational cohort study, significant racial and ethnic disparities were observed in the incidence and psychological effects of PCIA. Asian women experienced the greatest burden. These findings underscore the need for personalized counseling, culturally sensitive psychosocial support, and consideration of pharmacogenetic risks in managing chemotherapy-related alopecia.