Sometimes, the cells in the skin can form small lesions that require treatment. Keratoacanthoma is a clinical condition where skin cells grow into a small tumour which is often localised and does not spread to any other part of the body. In this article, we shall briefly review keratoacanthoma and how it is treated.

What is a keratoacanthoma?

Keratoacanthoma is a skin tumour that appears like a small boil on the surface of the skin. Once it appears, it starts to grow rather rapidly and can reach a significant size within a matter of weeks. Its appearance is a rather typical and numerous a times, untreated keratoacanthoma is will eventually disappear though they would leave a scar. A keratoacanthoma can take up to 4 to 6 months for complete resolution.

What causes a keratoacanthoma?

The primary reason for the development of a keratoacanthoma is exposure of the skin to ultraviolet rays of the sun. A rare few cases have been linked to the {human} papilloma virus.

Types of keratoacanthoma

There are various types of keratoacanthoma. While a detailed discussion is out of the scope of this article, it is worthwhile remembering that keratoacanthomas could be a solitary lesion (called solitary keratoacanthoma), could be multiple (called multiple keratoacanthoma) or maybe a rather large (known as giant keratoacanthoma). Sometimes, multiple lesions could arise in different parts the body and this is known as generalised eruptive keratoacanthoma. Similarly, multiple lesions could also arise in one part of the body and this is known as keratoacanthoma centrifugum marginatum.

How is keratoacanthoma diagnosed?

Diagnosis can be easily made from history and clinical examination. Keratoacanthomas have a characteristic appearance upon inspection. However, often just a clinical diagnosis is insufficient and confirmation is required through additional tests. A skin biopsy is helpful and this will reveal the presence of small fragments of keratin which is a part of normal skin tissue. Other additional findings will also be demonstrated which can help confirm the diagnosis.

Treatment options

There are different treatment options available in managing keratoacanthoma. The choice of treatment depends upon where exactly the tumour is located. When the tumour is located on the trunk, arms and legs, simple procedures such as curettage and electrodesiccation are sufficient.

If the lesions occur on the face, a special surgical procedure known as Mohs surgery is performed. Here, the entire keratoacanthoma is removed along with the surrounding skin margins in order to prevent it from recurring.

In the event that multiple keratoacanthomas develop on the skin, surgical options could not be appropriate and using drugs such as isotretinoin are useful. Steroids and other special medication such as methotrexate and bleomycin have been used with a degree of success. Treatment is best offered by expert dermatologists who have managed patients would keratoacanthomas in the past. The input of a plastic surgeon could be required.

Unfortunately, patients who suffer a keratoacanthoma can experience recurrences despite adequate medical and surgical therapies.


A keratoacanthoma is a low-grade skin tumour that can be localised or spread all across the body. Treatments are variable and depend upon the site and number of the tumours. Long-term outcomes are good though recurrence rates are high.