Many years of sun exposure can cause actinic keratoses to develop on the skin.
Actinic keratoses are rough and scaly and appear in various colors.
The diagnosis is usually based on a doctor's evaluation.
Growths can be removed by physical means or by various treatments applied to the skin.
(See also Overview of Sunlight and Skin Damage Overview of Sunlight and Skin Damage Sunlight stimulates vitamin D production, helps control some chronic skin diseases (such as psoriasis), and causes a sense of well-being. However, sunlight can cause skin damage. Damage includes... read more 
.)
Actinic keratoses are very common. As people age, they are likely to develop them. Actinic keratoses can progress to squamous cell carcinoma Squamous Cell Carcinoma Squamous cell carcinoma is cancer that begins in the squamous cells of the skin. Thick, scaly growths appear on the skin and do not heal. To diagnose the cancer, doctors do a biopsy. Treatment... read more 
, a type of skin cancer. Growths that do not progress to squamous cell carcinoma may go away or stay actinic keratoses. Growths that go away may return.
In addition to many years of sun exposure, other risk factors for actinic keratoses include older age, an impaired immune system, blond or red hair, blue eyes, and skin type I or II (see table ).
Symptoms of Actinic Keratoses
Actinic keratoses are usually pink, red, or, less commonly, gray or brown. They feel rough and scaly.
The growths frequently develop in sun-exposed areas (for example, lips, bald scalp, face, neck, or the backs of hands and forearms).
Diagnosis of Actinic Keratoses
A doctor's examination
Doctors diagnose actinic keratoses by looking at and touching them. Because of their rough texture, actinic keratoses are often easier to feel than see. Doctors also differentiate them from seborrheic keratoses Seborrheic Keratoses Seborrheic keratoses (seborrheic warts) are usually warty and skin-colored, brown, or black growths that can appear anywhere on the skin. (See also Overview of Skin Growths.) The cause of seborrheic... read more 
, which can look similar to actinic keratoses.
Treatment of Actinic Keratoses
Physical removal or products applied to the skin
People should take precautions to minimize the damaging effects of the sun (see sunburn prevention Prevention Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more 
). Damage that is already done is difficult to reverse.
Actinic keratoses are treated depending on the number of growths, where the growths are located, and what therapy people can tolerate.
If a person has only a few growths or is unable to tolerate other treatments methods, doctors usually remove them by freezing them with liquid nitrogen (cryotherapy) or scraping (curetting) them off. These treatment options are the quickest but have a higher risk of leaving a scar compared to other treatment options.
If a person has many growths, doctors give people creams, gels, or ointments they can apply to their skin (topically). A liquid or cream containing fluorouracil (a chemotherapy medication applied to the skin) is commonly used. Often, during such treatment, the skin temporarily looks worse because fluorouracil causes redness, scaling, and burning of the keratoses and of the surrounding sun-damaged skin.
Imiquimod is useful in treating actinic keratoses because it helps the immune system to recognize and destroy precancerous skin growths and early skin cancer. Imiquimod cream is applied to the skin. Imiquimod causes redness, scaling, and burning similar to that caused by fluorouracil.
Diclofenac gel is a nonsteroidal anti-inflammatory drug (NSAID) that is applied to the skin for 2 to 3 months. It may cause mild to moderately severe skin problems such as rash, redness, itching, dry skin, and skin irritation. It is less effective than fluorouracil and imiquimod.
Tirbanibulin is a newer medication that works by killing fast-growing abnormal cells. The ointment is currently recommended to be applied to the face or scalp for 5 days. It may need to be applied for a longer period of time because it is common for keratoses to return after using this treatment. Tirbanibulin may cause itching and pain where applied.
Another treatment is photodynamic therapy, in which a chemical preparation is applied to the skin and then artificial light is applied to the growths. This therapy causes a sunburn-like appearance. The main advantage of photodynamic therapy is that it typically entails fewer days overall of skin redness, scaling, and irritation. People may need more than one treatment session.
If a person is not helped by any of these treatments, doctors may do a biopsy to rule out squamous cell carcinoma Squamous Cell Carcinoma Squamous cell carcinoma is cancer that begins in the squamous cells of the skin. Thick, scaly growths appear on the skin and do not heal. To diagnose the cancer, doctors do a biopsy. Treatment... read more .
