Keratoacanthomas

Keratoacanthomas is a very common skin lesion that occurs on sun-damaged skin. They may frequently arise on the face, ears, nose and limbs. Keratoacanthomas are thought to be a variant of an SCC, but KAs may resolve over months. Skin Cancer Doctors will often take a biopsy to tell the difference between KAs and SCCs. Keratoacanthomas present as a warty growth that can erupt over days to weeks, and rapidly grow over time. Early identification is best management.

Important Facts on Keratoacanthomas

Theses are very common skin tumors occurring on sun-damage skin
Sometimes these tumors undergo spontaneous resolution without the need for surgery
KAs or Keratoacanthomas will need to be differentiated from SCCs and hence skin cancer specialist will often take a biopsy
Treatments include medical, surgical or radiotherapy
The prognosis following excision of Keratoacanthoma is excellent
KAs often occur on the background of sun-damaged skin, and hence regular checks for other skin cancers are essential
Skin cancer doctors in Brisbane see a large number of KAs, especially in patients who suffer from sun-damaged skin

What is a Keratoacanthoma?

Keratoacanthomas are wart like lesions that occur on UV exposed sites, such as the ears, nose, face and limbs. They are most commonly seen in elderly patients, especially those who have a background of sun-damage. They are thought to be related to a more sinister skin cancer called a Squamous Cell Cancer.

Why has Brisbane got a higher incidence of KAs per capita compared to southern cities such as Canberra and Sydney?

The high UV index of Brisbane contributes to the formation of Keratoacanthomas. The incidence of KAs per capita is higher in northern cities and towns compared to Melbourne or Sydney.

Who is at risk for developingKeratoacanthomas?

Risk factors include patients who have had lots of UV exposure in early life, as well as immune suppressed people. Very rarely, KAs maybe associated with families or genetic conditions and syndromes.

What does a Keratoacanthoma look like?

This lesion typically looks like a volcano, with a crater in the middle. KAs are very fast growing skin cancers, typically doubling in size every few weeks.

In England we use to call this a 6-6-6 tumour, 6 weeks to reach maximum size, 6 weeks to stay, and if it resolves it will take 6 weeks. It is advisable not to have the ‘wait and see’ approach as KAs may resemble more sinister cancers such as SCCs.

What causes Keratoacanthomas to form?

Major causes of KAs include-
1. Genetics
2. UV radiation
3. Immune suppression
4. Trauma
5. Some cases related to HPV infection
6. Rare genetic conditions

How do skin cancer doctors diagnose a Keratoacanthoma?

In most cases the clinical findings coupled with the history of rapid grown clinches the diagnosis. A biopsy is performed for testing, prior to treatment.

What treatment options do I have for Keratoacanthomas?

Skin Cancer Doctors at My Skin Clinics always treat KAs. Observation is NOT an option. This is because KAs can resemble a nasty skin cancer called an SCC.

Treatment options for KAs include-

1. Surgery: most common treatment with highest cure rate
2. Curette: Great treatment for KAs and frequently used by dermatologists
3. Radiotherapy- great for marginal KAs and in the elderly

What follow up do I need after Keratoacanthoma treatment?

A check up by your skin cancer doctor every 4-6 months will be recommended to pick up other forms of skin cancer associated with KAs.

What is the prognosis of a Keratoacanthoma?

Excellent. Once removed by surgery, KAs very seldom recur. (Exceptions are centrifugum varieties, genetic KAs seen in England, and immune suppressed patients).

What is important is that patients who have had KAs ensure that they have their skin checked at least once every 4-6 months for other forms of skin cancers. KAs often occur in sun-damaged skin, associated with solar keratosis, BCCS and even melanomas. Your skin cancer doctor will guide you in regards to follow up intervals.

My Skin Cancer Clinics view on KAs

Keratoacanthomas are very common skin cancers seen in Queensland. The high UV index of Brisbane and other northern cities predisposes to KAs. Fortunately this form of skin cancer is less aggressive than melanomas and SCCs. In fact, death is very, very, very rare following a KA.

Skin cancer doctors at My Skin Clinics are trained to diagnose, manage and follow up patients with this common, but relatively harmless tumour. Early management is the key.