Cutaneous horn

• this is a relatively rare tumour, most often arising on sun-exposed skin in elderly men
• important issue is not the horn itself, which is dead keratin, but rather the underlying condition, which may be benign, premalignant, or malignant

Various types of associated lesions may be found at the base of a cutaneous horn, including viral warts, actinic keratosis, keratoacanthoma, seborrheic keratosis, pyogenic granuloma, discoid lupus erythermatosus, verruca vulgaris, Bowen's disease, basal cell carcinoma, and squamous cell carcinoma

Click here for image of a cutaneous horn

Risk of lesion underlying the cutaneous horn being premalignant or malignant

• in a study performed on 48 cases with eyelid horns, by Mencía-Gutiérrez et al., 23% of them were premalignant and malignant
• clinically determing whether the underlying lesion is malignant or premalignant is very difficult on clinical grounds
  • larger size of lesions and tenderness at base of lesions are signs in favour of malignancy (5)

Treatment

• depends on the type of lesion and its malignant potential
• prompt diagnosis of the underlying lesion by appropriate biopsy is mandatory
  • if the lesion is benign then biopsy may be both diagnostic and therapeutic
  • malignant lesions will require complete surgical excision with an appropriate margin

Take home message:

• if patient with cutaneous horn, an underlying disease must be looked for
  • given the possible malignant underlying condition then a 2 week referral for dermatology review is required (6)

Reference:

• 1) Bondeson J. Everard home, John hunter, and cutaneous horns: A historical review. Am J Dermatopathol. 2001;23:362-9
• 2) Nthumba PM. Giant cutaneous horn in an African woman: A case report. J Med Case Reports. 2007;1:170.
• 3) Vano-Galvan S, Sanchez-Olaso A. Images in clinical medicine.Squamous cell carcinoma manifesting as a cutaneous horn. N Engl J Med. 2008;359:e10.
• 4). Gould JW, Brodell RT. Giant cutaneous horn associated with verruca vulgaris. Cutis. 1999;64:111-2.
• 5) Mencía-Gutiérrez E, Gutiérrez-Díaz E, Redondo-Marcos I, Ricoy JR, García-Torre JP. Cutaneous horns of the eyelid: A clinicopathological study of 48 cases. J Cutan Pathol. 2004;31:539-43
• 6) Primary Care Dermatological Society. Cutaneous horn (Accessed 29/7/14)