Actinic keratosis

Actinic (or solar) keratosis is a skin condition that can develop in the top layer of skin with age and is primarily found on sun-exposed parts of the body. Fair-skinned people are more susceptible to it and men are more likely to develop it than women.

It is a very common condition and it is estimated that over 23% of the UK population aged 60 and over is affected. It is a pre-cancerous condition and the risk of its developing into a squamous cell carcinoma is very low.

However, this risk increases over time in the presence of large numbers of lesions and vigilance is called for. Signs to look out for are if the patches grow, bleed or visibly change.

In appearance, the patches can be red, pink, brown or skin-coloured and they are rough or scaly in texture, similar to sandpaper. They can resemble warts and vary from a few millimetres to a centimetre or so in size. They are normally asymptomatic but can be itchy.

If they are not raised and can barely be felt, the treatment of choice would be a simple moisturizer and education on meticulous sun protection.

If, on the other hand, they are raised, slightly indurated or scaly, there are a number of treatments available:

Cryotherapy, using liquid nitrogen, and freezing the affected area for 10 seconds or so would cause destruction of the abnormal cells. This would cause a degree of inflammation and may result in blistering, which would soon heal up.

Another treatment would be curettage. Here, under local anaesthetic, the lesion is scraped away and cauterized. The benefit of this approach is that the specimen can be sent for off for microscopic analysis.

There are also many non-surgical ways of treating this condition. Topical creams can be applied, and new techniques, such as photodynamic therapy, are available. This involves the application of a cream called Metvix, followed some three hours later by shining a red light on the area, causing a photochemical reaction which kills off the abnormal cells.

In the case of multiple actinic keratoses, a cream called Efudix can be effective over a period of three or four weeks. This does cause an inflammatory reaction but patients are advised about this before they undergo this treatment.

For these larger areas of actinic keratosis, there are other creams available, and your dermatologist will advise on the treatment of choice in your particular case.