摘要

Objectives: Participants will learn to recognize dermoscopic patterns of nail pigmentation, differentiate benign from malignant nail lesions, identify conditions mimicking subungual melanoma, and understand when biopsy is required. The session aims to enhance diagnostic confidence and promote appropriate clinical decision-making using nail dermoscopy. Introduction: Nail pigmentation and tumors often present diagnostic difficulties due to overlapping clinical features. Subungual melanoma, although rare, is potentially fatal if diagnosed late. Nail dermoscopy provides detailed visualization of nail structures, allowing early recognition of malignant patterns and accurate differentiation from benign conditions such as hematoma, nevus, fungal infection, or ethnic pigmentation. Materials / method: Nail dermoscopy was performed using a polarized dermatoscope to examine nail plate, bed, and matrix. Pigment distribution, color, line regularity, background pattern, and periungual involvement were assessed. Lesions were classified as melanocytic or non-melanocytic. Dermoscopic findings were correlated with clinical features, and biopsy was performed in suspicious or progressive cases. Results: Dermoscopy enabled differentiation between subungual hemorrhage, melanonychia striata, lentigo, drug-induced and ethnic pigmentation, and melanoma. Benign lesions showed regular lines and homogeneous coloration, while melanoma demonstrated irregular lines, color variation, and blurred borders. Dermoscopy also improved recognition of nail tumors such as onychopapilloma, onychomatricoma, and glomus tumor. Conclusion: Nail dermoscopy is a valuable tool in daily dermatologic practice for the diagnosis and monitoring of nail disorders and early detection of subungual melanoma. When used by experienced clinicians, it reduces unnecessary biopsies while ensuring timely intervention for malignant lesions. Biopsy remains mandatory when dermoscopic features are suspicious or inconclusive.