Solar Keratoses

Solar/ Actinic Keratosis:

What You Should Know About This Common Pre-Cancer

You have surely seen an actinic keratosis. The name may be unfamiliar, but the appearance is commonplace. Anyone who spends time in the sun runs a high risk of developing one or more.

What is it?

An actinic keratosis (AK), also known as a solar keratosis, is a scaly or crusty bump that arises on the skin surface. The base may be light or dark, tan, pink, red, or a combination of these. . . or the same color as your skin. The scale or crust is horny, dry, and rough, and is often recognized by touch rather than sight. Occasionally it itches or produces a pricking or tender sensation. It can also become inflamed and surrounded by redness. In rare instances, actinic keratoses can even bleed.

The skin abnormality or lesion develops slowly and generally reaches a size from an eighth to a quarter of an inch. Early on, it may disappear only to reappear later. You will often see several AKs at a time.

An AK is most likely to appear on the face, ears, scalp, neck, backs of the hands and forearms, shoulders, and lips – the parts of the body most often exposed to sunshine. The growths may be flat and pink or raised and rough.

Why is it dangerous?

AK can be the first step in the development of skin cancer. It is thus a precursor of cancer or a precancer.

If treated early, almost all AKs can be eliminated without becoming skin cancers. But untreated, about two to five percent of these lesions may progress to squamous cell carcinomas. In fact, some scientists now believe that AK is the earliest form of SCC. These cancers are usually not life-threatening, provided they are detected and treated in the early stages. However, if this is not done, they can grow large and invade the surrounding tissues and, on rare occasions, metastasize or spread to the internal organs.

Another form of AK, actinic cheilitis, develops on the lips and may evolve into a type of SCC that can spread rapidly to other parts of the body.

If you have AKs, it indicates that you have sustained sun damage and could develop any kind of skin cancer – not just squamous cell carcinoma. The more
keratoses that you have, the greater the chance that one or more may turn into skin cancer. People may also have up to 10 times as many subclinical (invisible) lesions as visible, surface lesions