The Impact of Immunotherapy on Hair Repigmentation in Patients With Thoracic Tumors: A Clinical Observation Based on Trichoscopy

OBJECTIVE: Whether hair repigmentation during cancer therapy is driven by immune checkpoint inhibitors (ICIs) or chemotherapy remains unclear. This study aimed to quantitatively identify the primary driver using a controlled design. METHODS: In this prospective study, 29 patients with thoracic malignancies were divided into an immunotherapy group (n = 18) and a chemotherapy group (n = 11). Standardized dermoscopic images were captured before and after treatment. Hair pigmentation was quantified via grayscale analysis. RESULTS: Grayscale values decreased significantly posttreatment in the immunotherapy group (p = 0.0008) but not in the chemotherapy group (p = 0.1427). The magnitude of change (ΔGrayscale) was significantly greater with immunotherapy than with chemotherapy alone (23.5 ± 24.67 vs. 4.32 ± 9.01; p = 0.0065), representing a large effect size (Cohen's d = 0.90). CONCLUSION: This controlled study provides quantitative evidence suggesting that immunotherapy, rather than chemotherapy, is closely associated with hair repigmentation. It establishes an objective methodological framework for future investigation of this phenomenon.