Subungual Ganglion Cyst Mimicking Glomus Tumor

Abstract

Subungual masses accompanying nail deformity are of common occurrence and uniquely confirmed by histopathologic examination postoperatively. Although glomus tumor is most frequently diagnosed with its specific clinical triad, other rarer diagnoses have also been reported. Though ganglion cysts are predominantly found around the distal phalangeal joint as a mucous cyst and myxoid cyst, they might also appear as a subungual mass accompanied by nail deformity thereby mimicking the glomus tumor. A 54-year-old woman visited our outpatient clinic with nail deformity and pain on the tip of the right thumb. She had a history of nail root injury on her right thumb which occurred 3 months back at a nail shop. Physical examination revealed a convex point with tenderness on the right thumbnail. Doppler ultrasonography revealed the presence of 0.43×0.26×0.53 cm3 sized non-specific cystic lesion with hypoechogenicity and no abnormal vascularity. Complete excision of the cyst was performed and histopathology revealed a ganglion cyst. Subungual ganglion cyst is rarely occurred and known to be usually asymptomatic. Herein, we report a case of ganglion cyst of subungual area which was mistakenly diagnosed as a glomus tumor preoperatively.