What Is a Histiocytoma? Understanding This Common Skin Tumor in Pets

By Lakeshore Road Animal Hospital

Have you noticed a small, round lump on your dog’s skin? It might be a histiocytoma, a common benign skin tumor especially found in young dogs. At Lakeshore Road Animal Hospital, we want to help you understand what histiocytomas are, how to spot them, and when to seek veterinary care.

What Is a Histiocytoma?

A histiocytoma is a harmless growth that appears as a small, raised, hairless lump on your dog’s skin. It often grows quickly but usually disappears on its own within a few weeks to months. These tumors are made up of immune system cells called histiocytes.

Who Gets Histiocytomas?

Histiocytomas most commonly occur in young dogs under 3 years old, though any dog can develop one. They usually appear on the head, ears, or limbs.

What Does a Histiocytoma Look Like?

You might see a button-like, red or pink bump that may be itchy or inflamed. Because they grow quickly, it’s important to have any new lumps checked by your veterinarian.

When Should You See the Vet?

If you notice a lump on your dog’s skin, especially one that grows quickly, changes in appearance, or doesn’t heal, bring your pet to Lakeshore Road Animal Hospital for an examination. We may perform a fine needle aspirate or biopsy to confirm the diagnosis.

Treatment and Prognosis

Most histiocytomas resolve without treatment. However, if the tumor is irritating your pet or becomes infected, your veterinarian may recommend removal. Regular monitoring ensures your pet stays healthy.