Verrucous carcinoma due to arsenic ingestion in a psoriasis patient

Verrucous carcinoma is a rare clinicopathologic entity caused by multifactorial influences. We report here a 64-year-old male patient presenting with a large exophytic mass in the right leg.

The patient had a 19-year duration of psoriasis and received various treatments. In his last year of life, he had been taking an illegally produced folk drug with the hope of controlling his psoriasis. However, 6 months after the drug ingestion, many papules appeared on his right leg, which eventually developed into a large tumor in the next few months. The patient died of acute pulmonary embolism only a week after hospitalization, when his tumor was pathologically confirmed as verrucous carcinoma. Later, the folk drug was analyzed and found to contain arsenic. The causative relevance of the tumor with his daily arsenic intake is discussed.