Neurothekeoma: Another differential in the diagnosis of a subungual swelling

Lesions, which commonly grow and protrude beneath the distal end of a toe nail and present to the podiatrist or foot and ankle surgeon, include subungual exostosis or enchondroma and a Nora lesion. Neurothekeoma is a benign dermal tumour of the peripheral nerve sheath that usually affects the skin of the head, neck, shoulders and arms. It occurs less commonly in the lower limbs and has only been reported twice in a subungual location. A case of subungual neurothekeoma that recurred twice due to inadequate margins of resection is presented.

Although rare, neurothekeoma should be included in the differential diagnosis of a subungual lesion. Histopathological diagnosis is reached by differential immunostaining. Adequate clear margins of resection are recommended to prevent recurrence.