CASE OF THE MONTH - June 2016

A painful nodule on the toe

Laura Del Regno, Ketty Peris

Institute of Dermatology, Catholic University, Rome, Italy

Case presentation: a 63-year-old woman presented with an exophytic, partially ulcerated, painful nodule located on the fifth toe of the left foot (Fig. 1A). The patient referred that the lesion had arisen approximately two years earlier as a small papule on the nail bed, and in time slowly increased in size. No other cutaneous lesions could be detected on physical examination. There was no history of warts, immune-suppression or previous exposure to radiation or chemicals.

Diagnostic work up, treatment and follow up: Histological examination of a skin biopsy specimen revealed a moderately to poorly differentiate squamous cell carcinoma (SCC) showing nests of neoplastic cells deriving from the nail bed and located in the whole dermis (Fig 1B), with focal keratinization and invasion of deep structures including the bone (Fig. 1C). Total body CT scan showed bone involvement of the distal phalanx of the left foot but no visceral metastases. Surgical treatment consisted of amputation of the fifth toe. After a follow-up of 18 months, there is no evidence of recurrence or metastases (Fig. 1D).

A painful nodule on the toe

Key message: Squamous cell carcinoma arising from the nail bed matrix and lateral skin folds is rare. It typically presents as a slow-growing, locally destructive lesion which in time may involve the underlying bone, as in our patient. Association with trauma, chronic infection and radiation has been reported. Clinical differential diagnosis may include verruca vulgaris, onycomycosis, paronychia, amelanotic melanoma and benign neoplasms, and therefore diagnosis in the early stage is crucial to provide the most conservative management.

References:

  1. Stratigos AGarbe CLebbe CMalvehy Jdel Marmol VPehamberger HPeris KBecker JCZalaudek ISaiag P,Middleton MRBastholt LTestori AGrob JJ1; European Dermatology Forum (EDF)European Association of Dermato-Oncology (EADO)European Organization for Research and Treatment of Cancer (EORTC). Diagnosis and treatment of invasive squamous cell carcinoma of the skin: European consensus-based interdisciplinary guideline. Eur J Cancer. 2015 Sep;51(14):1989-2007. doi: 10.1016/j.ejca.2015.06.110. Epub 2015 Jul 25.
  2. Alfonso JH, Martinsen JIPukkala EWeiderpass ETryggvadottir LNordby KCKjærheim K. Occupation and relative risk of cutaneous squamous cell carcinoma (cSCC): A 45-year follow-up study in 4 Nordic countries. J Am Acad Dermatol. 2016 Jun 1. pii: S0190-9622(16)30018-4. doi: 10.1016/j.jaad.2016.03.033. [Epub ahead of print]