Cutaneous horns, also known by the Latin name cornu cutaneum, are unusual skin tumours, formed from keratin, with the appearance of horns, or sometimes of wood or coral.

They are usually small and localized. Although often benign, they can also be malignant or pre-malignant.

Their cause is unknown. Suggestions include influence of the HPV (wart) virus, and exposure to radiation or other environmental triggers, including injuries.

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