Actinic keratosis, also called solar keratosis or senile keratosis, can be considered a precancerous skin condition. Causes of actinic keratosis include exposure to UV radiation from the sun or commercial tanning beds and lamps. Damage to the DNA of epidermal cells causes them to develop abnormalities in size, shape and organization. The result from these changes are lesions or plaques on the skin’s surface. Actinic keratosis is characterized by thick, scaly or crusty patches of skin. There are many factors for developing actinic keratosis including type of skin, hair color, eye color, amount of sun exposure and age. Several treatments are available including cryotherapy, chemical peels, photodynamic therapy and 5-Fluorouracil (5-FU).
While actinic keratosis can be caused by carcinogens, or cancer-causing agents, like exposure to radiation and chemicals, the most common cause of actinic keratosis is exposure to ultraviolet light produced by the sun or commercial sun beds and lamps. Much like squamous and basal cell carcinoma, actinic keratosis is generally caused by long-term, cumulative sun exposure. This is why actinic keratosis is often referred to as solar keratosis. Ultraviolet light damages the DNA of epidermal skin cells, which causes them to develop abnormalities in size, shape, and organization. These changes may cause the cells to divide uncontrollably, resulting in a lesion or plaque on the skin’s surface. Left untreated, the damaged cells can become cancerous with time.
As actinic keratosis generally develops in areas of the body that have been exposed to large amounts of sun, the condition is most often seen on the face, ears, neck, lips, forearms and hands. Actinic keratoses appear as rough, callous, scaly lesions or plaques on the skin’s surface. Although dry, rough patches are characteristic, actinic keratoses may also present as oozing lesions that do not heal or as thick, horny growths. Lesions may vary in color from light beige tones to dark brown and range in size from a small dot to approximately an inch in diameter. In addition, they may seem to appear and disappear periodically, or they may remain in place for a long period of time. Actinic keratosis can look like certain types of skin cancer, especially squamous cell carcinoma. This is why it is important to contact a dermatologist to determine the nature of any suspicious lesion on your skin.
Just as certain individuals are at a higher risk for developing sunburn than others, some people are at a higher risk for developing actinic keratosis. In general, those with fair skin and blond or red hair develop actinic keratosis at a higher rate than those individuals with darker complexions. Because actinic keratosis is primarily linked to sun exposure, people who live in sunny areas or who spend a significant amount of time in the sun without proper protection are also at a higher risk of developing the condition. DNA damage that occurs from occasional sun exposure is usually repaired by built-in DNA repair mechanisms in your body. However, long-term sun exposure can lead to DNA damage that is not repaired. This is why the effects of sun damage are not usually evident for many years, and why actinic keratosis is most commonly observed after the age of forty.
A dermatologist will be able to diagnose actinic keratosis during a skin examination. However, large, thick or otherwise questionable lesions sometimes require a small sample, called a skin biopsy, to be taken to ensure that it has not become skin cancer. Not all types of keratoses need to be removed, but you should consult with a dermatologist, who will make a determination based on the type of lesion, your health condition and age. Fortunately, there are a variety of treatments.+Cryotherapy