An unusual case of sporotrichoid nodules: Metastatic cutaneous squamous cell carcinoma

Abstract

A 63-year-old immunocompetent patient presented with a 4 month history of 12 painless nodules in a linear array on his right arm. He had a history of a surgery for a cutaneous tumor on the dorsum of his right middle finger about a year prior, but he did not follow up after the surgery. A differential diagnosis of sporotrichosis, atypical mycobacteria, deep fungal infection, and metastatic cutaneous squamous cell carcinoma (SCC) was considered. Skin biopsy revealed islands of dysplastic squamous cells and keratin pearls in a desmoplastic stroma in the deep dermis and subcutaneous tissue. The behavior of the disease was very aggressive, with rapid dissemination in a linear array, mimicking an infectious sporotrichoid spread. To our knowledge, this is the second case report of sporotrichoid metastases to the skin from cutaneous SCC in an immunocompetent patient.