Faculty Bibliography

Alopecia is a medical condition that impact many people worldwide and has diverse causes, ranging from autoimmune to genetic factors. Hair transplantation represents a key therapeutic option for patients with progressive hair loss who are seeking improvement beyond the capacity of medications or less invasive procedures. While hair transplantation is most commonly utilized for androgenetic alopecia, individuals with other alopecia diagnoses may also benefit. The two main techniques for hair transplantation include follicular unit transplantation and follicular unit excision. Hair transplantation is particularly important given the profound psychosocial implications and cosmetic disfigurement associated with alopecia. Chronic hair loss patients may experience reduced self-esteem, increased depression and anxiety, and poorer quality of life. Despite the significance of hair transplantation, comprehensive guidelines informing the clinical and surgical management of transplant candidates remain limited. Therefore, this review aims to explore patient candidacy criteria, pretransplant medical therapy optimization, intraoperative considerations, and postoperative complications and medical management.

IMPORTANCE/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED:Standardized trichoscopic assessments were performed and validated distress questionnaires were administered at baseline and 12 months after treatment. MAIN OUTCOMES AND MEASURES/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED: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.

Hair traits are nonpathogenic features that vary among individuals. Unlike hair follicle (HF) diseases, which are rare in the population, hair traits can be measured in everyone. This facilitates the construction of large cohorts that are well-powered for gene discovery. GWASs identify genetic variants that are widely shared among people globally, providing knowledge with broad population relevance. We compile findings from hair trait GWASs to deepen our understanding of HF biology. In reviewing genetic factors that influence hair traits, we demonstrate overlap with disease genes, underscoring that genetic studies of traits improve our knowledge about health and disease.