A cutaneous horn is more a sign than a specific diagnosis. Cutaneous horns are hyperkeratotic, conical projections from the skin arising from benign or malignant lesions. They can occur almost anywhere on the skin but are more commonly found on sun-exposed surfaces.
A common cause of a cutaneous horn is an actinic keratosis at the base of the horn; a cutaneous horn caused by an actinic keratosis must be distinguished from one arising from a squamous cell carcinoma (SCC), which may be present at the base of a cutaneous horn.
Cutaneous horns most frequently occur in elderly individuals, though they are occasionally seen in children (almost always as warts). In adults, the most common scenario is a cutaneous horn of the face, scalp, or ear presenting with a SCC at the base. Warts and seborrheic keratoses are common benign lesions that may also be seen at the base of a cutaneous horn.
Immunocompromised Patient Considerations: Immunocompromised patients are prone to SCC, especially on sun-exposed areas, and these may present as cutaneous horns.
Pediatric Patient Considerations: When cutaneous horns occur in children, a wart is frequently the cause.
Codes
ICD10CM: L85.8 – Other specified epidermal thickening
A cutaneous horn, also known as cornu cutaneum, refers to a specific appearance of a skin lesion in which a cone-shaped protuberance arises on the skin caused by overgrowth of the most superficial layer of skin (epidermis). A cutaneous horn is not a particular lesion but is a reaction pattern of the skin. Approximately 40% of cutaneous horns represent precancerous lesions called actinic keratoses. Cutaneous horns may also overlie skin cancer. When overlying cancerous skin, squamous cell carcinoma is typically at the base of the cutaneous horn, but basal cell carcinoma is also possible.
Who’s At Risk
Cutaneous horns most often occur in adults, usually elderly, individuals with light skin with a history of significant sun exposure.
Signs & Symptoms
A cutaneous horn most often occurs on sun-exposed areas and appears as a cone-shaped protuberance arising from a skin-colored to red/pink bump or flat lesion.
Self-Care Guidelines
None necessary.
When to Seek Medical Care
Seek medical evaluation if a cutaneous horn is noted. A biopsy may be needed to assess whether the lesion is benign, precancerous, or cancerous.
Treatments
If the lesion is benign, no further treatment may be needed.
If the lesion is precancerous, the physician may:
Freeze the lesion with liquid nitrogen.
Use a topical chemotherapy agent, such as 5-Fluorouracil or a topical medicine that stimulates the immune system, imiquimod.
Scrape and burn (curettage and electrodesiccation) the lesion.
If the lesion is cancerous, the physician may:
Perform surgery.
Use a topical chemotherapy agent, such as 5-Fluorouracil or a topical medicine that stimulates the immune system, imiquimod.
Scrape and burn (curettage and electrodesiccation) the lesion.
Recommend radiation therapy.
References
Bolognia, Jean L., ed. Dermatology, pp.1715. New York: Mosby, 2003.
Patient Information for Cutaneous horn