Multiple cutaneous carcinoma arising from arsenic-containing traditional Chinese medicine in a patient with psoriasis: A case report

Background: Arsenic exposure is closely related to keratosis and cutaneous carcinoma, but a few studies have focused on patients with psoriasis presenting carcinoma after long-term medication of arsenic-containing traditional Chinese medicine (TCM). Case description: We presented a psoriasis patient showing multiple cutaneous carcinoma arising from arsenic containing TCM. A 60-year-old gentleman with psoriasis for nearly 30 years presented to our department with severe keratosis in hands, trunk and feet. He received oral administration of realgar (with As4S4 as the major component) for at least 15 years. There were keratotic plaques, ulcer and exudate in the middle finger and forefinger of left hand, and middle finger, forefinger and ring finger of the right hand. Moreover, brown papule was seen in right sole, together with keratotic plaques and ulcer in the left heel. Pathological analysis revealed basal cell carcinoma (BCC) in the anterior chest, right hand and right foot, Bowen disease in left hand and right hand, as well as squamous cell carcinomas (SCC) in right hand. Conclusion: This is a rare arsenic-exposure psoriasis patient showed coexistence of Bowen disease in left hand and right hand, BCC in the thoracic site, right hand and right foot, as well as SCC in right hand.