Subungual Tumors: Clinicopathologic Correlation with US and MR Imaging Findings

Abstract

Various types of tumors can affect the subungual space, including benign solid tumors (glomus tumor, subungual exostosis, soft-tissue chondroma, keratoacanthoma, hemangioma, lobular capillary hemangioma), benign cystic lesions (epidermal and mucoid cysts), and malignant tumors (squamous cell carcinoma, malignant melanoma). Imaging plays an important role in the detection and differentiation of subungual tumors because of their small size, nonspecific clinical manifestations, and functional significance. Ultrasonography (US)-in particular, high-resolution US with color Doppler studies-provides useful information regarding tumor size, location, shape, and internal characteristics (cystic, solid, or mixed), but it is limited in the further characterization of tissue. Magnetic resonance (MR) imaging has an important role in categorizing tumors according to their anatomic location, pathologic origin, and signal characteristics. There is some overlap between the US and MR imaging features of subungual tumors; however, certain features can allow accurate diagnosis and expedite management when correlated with clinical and pathologic findings.

Subungual onychomycosis due to Aspergillus niger mimicking a glomus tumor: A case report

“…MRI is helpful in making differential diagnosis. It shows low signal intensity on T1-weighted images, high signal intensity on T2-weighted fat-suppression images and enhancement on gadolinium-enhanced images (9). In the present case, bone erosion was shown in the radiograph and MRI showed low signal intensity on T1-weighted images and high signal intensity on T2-weighted images, although gadolinium-enhanced images were not performed.…”

“…In some of the cases, cortical thinning or erosive changes are shown in the adjacent bone in radiograph (9). MRI is helpful in making differential diagnosis.…”

Test yourself: index finger subungual pain

“…The differental diagnosis for nail bed pain includes trauma; degenerative manifestations such as osteophytes and mucous cysts; foreign body and granulomatous reactions; epidermal inclusion cysts; benign neoplasms such as hemangioma, soft tissue chondroma, osteoid osteoma, and glomus tumor; and, rarely, malignant lesions such as squamous cell carcinoma, melanoma, and metastatic disease [1]. Radiographs of the patient's hand demonstrated no significant abnormality aside from equivoval scalloping of the index finger dorsal cortex at the nail bed (Fig.…”

“…Glomus tumors arise from modified smooth muscle cells within the glomus body [4]. Approximately 75 % of glomus tumors occur in the hand and are most often located in the subungual space [1,3,5]. Glomus tumors typically present between 30 and 50 years of age and have equal prevalence in women and men [2].…”

“…Otherwise, glomus tumors are not associated with any radiographic findings. Chondromas and hemangiomas of the finger tips can develop internal mineralization that can be detected on radiographs, whereas glomus tumors do not [1]. On MRI examination, a glomus tumor typically has high signal on T2-weighted images and demonstrates avid enhancement after contrast administration [1].…”