Cutaneous horn


Cutaneous horns, also known by the Latin name cornu cutaneum, are unusual keratinous skin tumors with the appearance of horns, or sometimes of wood or coral. Formally, this is a clinical diagnosis for a "conical projection above the surface of the skin." They are usually small and localized but can, in very rare cases, be much larger. Although often benign, they can also be malignant or premalignant.

Signs and symptoms

The lesion at the base of the keratin mound is benign in the majority of cases. Malignancy is present in up to 20% of cases, with squamous-cell carcinoma being the most common type. The incidence of squamous-cell carcinoma increases to 37% when the cutaneous horn is present on the penis.

Cause

The cause of cutaneous horns is still unknown, but it is believed that exposure to radiation can trigger the condition. This is evidenced by a higher rate of cases occurring on the face and hands, areas that are often exposed to sunlight. Moreover, there is a higher prevalence in Asian countries with a warm climate. Other cases have reported cutaneous horns arising from burn scars. As with many other wart-like skin conditions, a link to the HPV virus family, especially the HPV-2 subtype, has been suggested.

Diagnosis

Histologically they are characterized by compact proliferation of keratin

Notable cases