A cutaneous horn is a type of lesion or growth that appears on the skin. It’s made of keratin, which is a protein that makes up the top layer of the skin. The growth may look like a cone or horn, and it can vary in size. The name comes from the growth sometimes resembling an animal’s horn.

This skin condition is more common in older adults, and both men and women can have it. Many cutaneous horns are benign or noncancerous, but they can also be precancerous or cancerous.

A cutaneous horn looks like a growth on the outside of the skin. This is the most common symptom. It can appear as a large bump, cone, spike, or horn. The growth may be the same color as the skin or it may be a different color. The color of the growth can vary and may be:

  • white
  • pink
  • yellow
  • tan
  • brown

Most cutaneous horns are curved, and the curvature can get worse as they grow.

Cutaneous horns can also appear on any part of the body. They are usually seen on the:

  • face
  • hands
  • ears
  • head
  • chest
  • arms

Areas of the body that are exposed more to the sun may be more likely to have these growths.

The exact cause of a cutaneous horn is often unknown. Exposure to radiation from the sunlight may be one of the causes. Another possible cause is having viral warts caused by human papillomavirus.

It’s estimated that about half of cutaneous horns appear on top of, or because of, skin cancer or precancerous skin lesions. Others may appear on top of, or because of, burn scars or other noncancerous skin conditions.

Older adults, especially ones between the ages of 60 and 70, are at a higher risk of developing cutaneous horns. Both men and women can get these growths, but men are more likely to have cancerous lesions. People with fair or light skin are also at a higher risk of having cutaneous horns.

Cutaneous horns aren’t contagious, so they can’t spread to other people.

Pain and inflammation are possible if a cutaneous horn is injured. Cutaneous horns may be a sign of cancer, so it’s important to call or see your doctor when a cutaneous horn first appears.

Symptoms that should trigger a call to your doctor:

  • a new cutaneous horn
  • pain and inflammation from the cutaneous horn or around it
  • redness or bleeding
  • rapid growth
  • hard or thickening skin at the base of the cutaneous horn

To diagnose a cutaneous horn, your doctor may ask for a medical history and do a physical exam. Most cutaneous horns are diagnosed based on their appearance.

In addition, your doctor may do a biopsy. During a biopsy, your doctor will usually remove the entire horn and send it to the lab to be examined under a microscope. That helps them diagnose the growth and determine whether or not any skin cancer is present.

The most common treatment for cutaneous horns is removal. The type of treatment you receive will also depend on if the growth is cancerous or noncancerous. Your recovery time will vary depending on the size of the growth and its type.

Treatment for noncancerous cutaneous horns may include:

  • removing the growth
  • freezing the growth with liquid nitrogen
  • scraping and burning the growth

Treatment for cancerous cutaneous horns may include:

  • removing the growth through surgery
  • scraping and burning the growth
  • using radiation therapy
  • using chemotherapy
  • using topical medicine to stimulate the immune system

Scarring is possible and often happens after removing a cutaneous horn. The size of the growth influences the amount of scarring.

In some cases, the cutaneous horns can reappear or grow back after removal.

Although there are no clear preventive measures that can stop cutaneous horns, avoiding exposure to the sun and using a high SPF-sunscreen may reduce your risk. Learn more about choosing a sunscreen.

A cutaneous horn isn’t contagious and can’t spread to other people. It’s a skin growth that can resemble a horn, cone, spike, or large bump. Cutaneous horns are more common among older adults and usually appear on parts of the body exposed to the sun.

It’s important to see a doctor right away after a cutaneous horn appears on the skin because it may be cancerous or a sign of skin cancer.