Features of a subungual glomus tumor:
(1) The patient develops subungual papule or nodule that may be erythematous, reddish-blue or skin colored.
(2) The lesion is very painful on exposure to pressure or cold temperatures. The pain may radiate.
(3) There is deformity of the distal nail plate.
(4) Erythronchychia (vertical reddish band in the nail) may be present proximal to the lesion.
Love's pin test is pressure applied with a pinhead or pencil tip to the lesion and adjacent tissue. The lesion is painful but adjacent tissue is not (Kitidumrongsook et al).
Differential diagnosis:
(1) acral lentiginous melanoma
(2) subungual exostosis
(3) pyogenic granuloma
(4) wart (verruca vulgaris)
(5) other bone tumor
(6) squamous cell carcinoma
Histologic examination of the resected lesion is needed to confirm the diagnosis.
The tumor needs to be completely excised or it may recur.
