With an aim to characterize the onychoscopic features of subungual
glomus tumors, we analyzed 15 cases presenting over 3 years, in this observational study. The clinical, onychoscopic, radiological, and operative findings in these patients were evaluated and correlated depending on the location and extent of the lesions.
RESULTS: All 15 patients (11 female and 4 male) had
pain as the presenting symptom and fulfilled the classic triad of paroxysmal
pain, cold sensitivity, and positive Love's pin test. Clinical nail plate findings included
onycholysis, onychorrhexis with distal splitting, and onychoschizia, while nail bed and matrix findings included localized erythematous and bluish patches, longitudinal
erythema, and altered lunula. Onychoscopy corroborated the clinical findings and revealed a more extensive area of involvement in five cases. Definitive onychoscopy findings included a localized structureless
erythema interspersed with bluish and patchy whitish areas (five cases of nail bed and six nail matrix
tumors) and a "candy-
cane appearance" (six cases, all large and lobulated nail matrix
tumors). MRI reported the
tumor in 13 cases, while two nail matrix
tumors were missed. Transungual excision revealed
tumors larger in size than predicted by MRI. The presence of candy-
cane appearance was consistent with lobulated matrix
tumors.
CONCLUSION: Onychoscopy improves the intraoperative detection of location and extent of subungual
glomus tumors. Nail bed and nail matrix
glomus tumors can have distinctive onychoscopic features that may help in better surgical planning.