Ultrasonographic appearance of subungual glomus tumors

To describe the sonographic (US) features of pathologically confirmed subungual glomus tumors.

We retrospectively analyzed cases of pathologically confirmed subungual glomus tumors in patients presenting between December 1, 2008 and October 31, 2012, selected from cases in the musculoskeletal US database of a single institution.

Data on 14 patients with pathologically proven glomus tumors were retrieved from the US database. The tumor size ranged from 1.9 to 10.0 mm (mean ± SD, 5.3 ± 2.3 mm). Well-circumscribed tumors with clear margins were identified on US in 12 cases (86%): 11 (92%) tumors were hypoechoic and 1 (8%) was isoechoic. On power or color Doppler US, 11 of these 12 tumors (92%) appeared hypervascular. Two of the 14 tumors did not show a clearly circumscribed mass on gray-scale US, and bony erosion was the only US finding in one of the two cases. Seven of the 14 patients (50%) showed focal bony erosion in the underlying phalangeal bone.

A hypervascular mass in the nail bed was the most common US finding associated with subungual glomus tumors. We found that focal hypervascularity supports the diagnosis, and bony erosion is commonly associated with digital glomus tumors.