Concurrent tinea pedis HPV-associated squamous cell carcinoma of the ventral toes treated with Mohs micrographic surgery

We present a case of human papillomavirus-associated squamous cell carcinoma arising between the ventral toes. A 60-year-old man presented with a 6-year history of a growth between the right fourth and fifth toes that had previously been thought to be secondary to hammertoe deformity. Initial biopsy favored verruca vulgaris with associated fungal hyphae and he was treated accordingly. Subsequent biopsy showed squamous cell carcinoma in situ with positive for high-risk human papillomavirus subtypes 16 and 18. He was successfully treated with Mohs surgery. This is the first published case of human papillomavirus 18-associated interdigital squamous cell carcinoma of the toes treated with Mohs surgery.