SymptomsCutaneous horns are usually asymptomatic. They can be injured causing pain and inflammation.Worrying features suggestive of malignancy
Whilst no certain features can confidently confirm or exclude malignant lesions, malignant lesions are more common in older patients and in males compared to females. Squamous cell carcinoma is also likely if the horn has the following features:
- Painful
- Large size
- Induration at the base
- The anatomic site on the nose, ears, backs of hands, scalp, forearms, face and penis
- Wide base or low height to base ratio
- Redness at the base of the horn base
- Lack of terrace formation, due to rapid unorganised growth.
Diagnosis and investigation of cutaneous horn
- A cutaneous horn is diagnosed by its clinical appearance.
- Histological examination of the horn base is crucial to rule out malignancy, as there are no certain clinical features that can definitively distinguish benign lesions from skin cancer.
- The lesion is usually completely excised. In some cases, a deep partial biopsy is taken to establish the diagnosis.
On histology, there is a thickening of the stratum corneum or hyperkeratosis. Orderly horizontal parallel layers of keratin are associated more with benign lesions. Rapidly growing malignant lesions exhibit more erratic growth. Acanthosis is often noted. The base of the lesion shows features of the underlying lesion.