Glomus-cell tumors are rare benign harmatomas of the glomus body, a specialized arteriovenous anastomosis located in the stratum reticularis of the dermis that is involved in thermoregulation. They represent 1-5% of soft tissue tumors of the hand  and are mostly located in subungual locations even if they can also rarely appear in extra-digital areas.
Clinically they appear in young adults (20-40 years) as small painful reddish subungual tumefactions. Pain is increased by pressure and by exposure to cold temperatures.
Imaging by MRI can help to precise the localization of the tumor and facilitate the pre-surgical evaluation of their size.
The treatment of glomus-cell tumors consists of a complete surgical removal of the lesion with histological examination. Intra-operative dermoscopy can help delimitate the tumor for an optimal resection, after anesthetic block, the use of a tourniquet (to avoid excessive bleeding) and careful avulsion of the nail plate.
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- When all you have is a dermatoscope- start looking at the nails. Dermatol Pract Concept. 2014;4:11-20.