Sunburn is damage caused to the skin when it is overexposed to ultraviolet light, such as from the sun. Sunburned skin changes colour to pink or red, and becomes swollen and tender. It can lead to premature ageing and even skin cancer. It is advisable to take preventative measures to avoid getting sunburnt.…
What is solar keratosis?
Solar keratosis, also known as actinic keratosis, is a condition where patches of skin can become rough and scaly caused by exposure to ultraviolet (UV) light. These skin changes are not cancerous, but there is a small risk that they can become squamous cell carcinoma.
Risk factors for solar keratosis include:
- Age - the risk of solar keratosis increases with age;
- UV radiation exposure - either short, intense exposure such as sunburn, or long-term accumulative exposure such as that gained from working outdoors;
- Sun tanning or using tanning beds;
- Having a family history of skin cancer;
- Having fair skin, and;
- Having a weakened immune system.
Signs and symptoms
Solar keratosis commonly appears on areas of the body exposed to sunlight, including the face, scalp, trunk of the body and back of the hands. Symptoms of solar keratosis include patches of skin appearing flat, scaly and yellow. Skin growths may also be pink, red, grey or skin color. They can develop to be hard, rough and wart-like.
Methods for diagnosis
Solar keratosis is mainly diagnosed upon its appearance. However, a skin biopsy may be performed if there is any doubt about the diagnosis, or concerns about cancerous change.
A biopsy is a tissue sample taken for microscopic examination in a laboratory. Local anesthetic may be used during biopsies. There are three types of skin biopsies:
- Incisional biopsies, which involve the removal of the entire abnormal area of skin with a surgical knife (scalpel);
- Punch biopsies, which involve the removal of a small circle of the whole skin layer, much like a hole-puncher removes holes in paper, and;
- Shave biopsies, which involve shaving off the top layer of skin.
Types of treatment
Solar keratosis lesions do not necessarily need to be treated. Some lesions can resolve if given time (usually within a year). Treatment may be recommended if lesions change in appearance or become tender. However, the importance of recognizing solar keratosis lesions, is the need for ongoing prevention. Wearing high sun protection factor (SPF) sunscreens, appropriate clothing to cover the body, and avoiding direct sunlight and tanning beds, can reduce the risk of developing further solar keratosis as well as other related skin cancers.
Lesions can be excised or scraped away, using a scalpel, curette, laser and/or electric current. The remaining wound can be closed with stitches and/or a wound dressing.
Lesions can be cautiously frozen off with liquid nitrogen, by an experienced health professional.
Creams, gels (water-based) and ointments (more greasy) containing certain medications, which reduce inflammation or target abnormal cells, can be applied directly to the skin. These can contain medications such as diclofenac, fluorouracil, imiquimod and salicyclic acid.
Photodynamic therapy (PDT)
Photodynamic therapy involves the application of a cream that is absorbed by abnormal cells and then a special light is applied, which selectively damages the abnormal cells.
Treatment side effects
- Skin ulceration - medicated creams have the potential to cause ulceration of the skin, particularly if used outside the recommended frequency or dosage;
- Persistent white marks or scarring - medicated creams and surgery can result in changes to skin color and scarring.
Advanced solar keratosis
Left untreated, solar keratosis can develop into a type of skin cancer called squamous cell carcinoma.
In the majority of cases, solar keratosis responds well to treatment.
The best way to prevent skin cancer is by minimizing your exposure to UV radiation, which can be done by avoiding sunlight during the times specific to your area, wearing protective clothing such as hats and long-sleeved shirts with collars and frequently applying sunscreen. Avoiding sun-tanning and tanning beds is also highly recommended.
- Actinic keratoses solar keratosis AK. DermNet NZ. Accessed 15 July 2014 from http://www.dermnetnz.org/lesions/solar-keratoses.html
- Actinic keratosis - National Library of Medicine - PubMed Health. Accessed 15 July 2014 from http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001830/
FAQ Frequently asked questions
What is solar keratosis?
Solar keratosis is a condition where patches of skin become rough and scaly, due to excessive exposure to sunlight.
What are the symptoms of solar keratosis?
The symptoms of solar keratosis can vary. The abnormal skin cells can appear scaly and yellow, red, pink, grey or skin colored. They can progress and appear more like a wart, becoming harder and developing a rougher surface.
Who develops solar keratosis?
Your risk of solar keratosis increases with age. It is higher if you have fair skin, work outdoors, sunbathe or use tanning beds, do not use sun protection, or if you have a weakened immune system.
How is solar keratosis diagnosed?
Your doctor will diagnose solar keratosis by examining your skin. A biopsy may be taken for a laboratory examination, if necessary.
How is solar keratosis treated?
There is a range of treatment options for solar keratosis, including surgery, medicated creams, cryotherapy and photodynamic therapy. It is also advisable to wear sunscreen to help reduce the formation of further lesions.
Can solar keratosis be prevented?
You can reduce your risk of solar keratosis by avoiding ultraviolet (UV) exposure and always using sun protection such as sunscreen, shade and appropriate clothing.
What is the outcome for solar keratosis?
In most cases, solar keratosis responds well to treatment. In some cases, however, the cells can become cancerous and develop into a squamous cell carcinoma. This can usually be treated, but the treatment is generally more extensive.
Is solar keratosis cancerous?
Solar keratosis is not generally cancerous but there is a small risk that it may develop into a cancer. If it changes in appearance or becomes tender, it may be worth getting it reviewed by a doctor.