Squamous cell carcinoma mimicking a wart

Sir, Cutaneous squamous cell carcinoma, a malignant proliferation of the cutaneous epithelium, represents the second most common non-melanoma skin cancer after basal cell carcinoma [1]. Verrucous carcinoma (VC) is a rare, low-grade, well-differentiated squamous cell carcinoma most commonly seen in the mucosa, infrequently reported to occur in the skin, where it is a slow-growing and locally aggressive tumor. It is not uncommon for cutaneous verrucous carcinomas to be mistaken for the more frequent wart (verruca vulgaris) and treated accordingly [2]. The etiopathogenesis of VC is not completely known. One theory mentions the human papillomavirus (HPV) infection; with plantar lesions, the types involved are reported to be 16 and 11 [3]. Histopathological diagnosis is difficult and needs one or more broad and in-depth biopsies. Morbidity results from the local destruction of the skin and soft tissues and, occasionally, from a perineural, muscular, and even bony invasion. Metastasis to regional lymphatic ganglia is rare, found in 5% of cases [4]. VC bears a high risk of local relapse. No matter the treatment employed, the rate of recurrence varies from 30% to 50% and usually is not the result of incomplete surgical interventions. The treatment of choice is complete surgical excision with safety margins [5]. A forty-year-old female patient with no previous history presented herself with a hyperkeratotic lesion on the right foot persistent for two years, which she had been manipulating routinely, which had progressively been increasing in size for the previous year, and which, for the previous three months, had become painful and bleeding. An examination revealed a hyperkeratotic plaque with a hyperpigmented border, hard on palpation, adherent to the deep plane, and with an eroded surface (Fig. 1). Dermoscopy was able to find a papillomatous appearance surrounded by dotted vessels (Fig. 2). This dermoscopic aspect typical of vulgar warts was confusing. Indeed, dermoscopy of the foot wart shows red or black dots in the center of papillomatous structures, which are thrombosed vessels supplying the wart; hence the importance, in our opinion, of the clinical and pathological correlation. For this reason, we performed a skin biopsy; an anatomopathological study found a squamous cell carcinoma of the verrucous type.