Supplementary Material for: A case report with Hutchinson‘s Sign: What could it be other than melanoma in situ?

Introduction: Many conditions such as malnutrition, radiation exposure, drugs, trauma, systemic and metabolic disorders can lead to nail pigmentation. Many other dermatological and systemic conditions, mycologic and bacterial infections, and repetitive trauma can be associated with non-melanoma-related Hutchinson’s sign.
Case presentation: We report a 68-year-old woman with the complaint of darkening of her existing nail bands and development of a newly-pigmented lesion on edge of her left thumb after taking chemotherapy. Lateral longitudinal biopsy including Hutchinson’s sign was performed. Melanocytes in normal number and localization in the nail matrix on histopathological evaluation. The patient was diagnosed with frictional hypermelanosis.
Conclusion: It’s very important to exclude subungual melanoma and to find out the etiology of Hutchinson’s sign. Repetitive trauma can be cause of non-melanoma Hutchinson’s sign.

引言：营养不良、辐射暴露、药物作用、创伤、系统性及代谢性疾病等多种病症均可引发甲色素沉着。另有诸多皮肤病、系统性疾病、真菌及细菌感染，以及反复创伤，可与非黑素瘤相关性哈钦逊征（Hutchinson’s sign）相关联。
病例报告：本文报告1例68岁女性患者，其原有甲带色素加深，且在接受化疗后左拇指边缘出现新发色素性皮损。术中对包含哈钦逊征区域进行了侧位纵向活检。经组织病理学评估，甲母质内黑素细胞数量及定位均正常。该患者最终被诊断为摩擦性色素沉着症。
结论：排除甲下黑素瘤并明确哈钦逊征的病因至关重要。反复创伤可作为非黑素瘤相关性哈钦逊征的诱因。