Squamous cell carcinoma of the nail unit (SCCnu) is the most common malignant tumor of the nail unit. It has a male predominance (sex ratio 2:1). Location is predominant in fingers, mainly the thumb and index. This could be due the more frequent exposure of the hands to trauma and oncogenic agents. It occurs most commonly in the fifth decade of life. They are usually single lesions, but polydactylous involvement has also been reported. Risk factors for SCCnu include trauma; immunosuppression; chronic paronychia; oral exposure to arsenic or pesticides; ionizing radiation exposure; dyskeratosis congenita; and infection with HPV subtypes 2, 11, 18, 26, 31, 34, 35, 52, 56, 58, 73, and especially type 16 (in 60%–80% of cases). Previous studies have shown that some Candida species produce carcinogenic nitrosamine compounds, thus chronic candida infection has also been proposed as a risk factor for SCCnu.