Cutaneous Horns or Cornu Cutaneum

A Horn on my skin, what can it be?

• Hyperkeratotic projections of the skin resembling the horn of an animal

• They look almost like a cone in shape

• Are composed of dead keratin derived from base keratinocytes (cells found in outer layer of the skin)

• Are usually grey to yellow in colour

• They are found mainly in locations, that have had solar exposure and damage

• They occur most frequently in light-skinned individuals older than 50 years of age and more common in men.

• These lesions can be several centimetres in size.

• They can be associated with benign, premalignant, or malignant tumours

• They are most frequently seen overlying an actinic keratosis

• However, they are also commonly associated with seborrheic keratosis and verruca vulgaris.

• They can also be due to cancers like squamous cell carcinoma or lentigo malignant melanoma

• When a cutaneous horn is observed, a biopsy is necessary to evaluate and determine the associated underlying tumour