Actinic keratosis
Actinickeratosis, or solar keratosis, is an area of sun-damaged skin occurring mostly in areas that are chronically exposed to ultraviolet (UV) radiation.
It is usually found on the face, bald scalp, forearms, back of the hands and lower legs.
Actinic keratoses can grow to a centimeter or two in diameter. Although at first they may be difficult to see, they are easily distinguished because they are usually rough, scaly patches. Their appearance is variable.
In fact, the same person can have different actinic keratoses of different colors, thicknesses, and sizes.




Are there different types of actinic keratosis?
Clinicians distinguish between several types of actinic keratosis based on how the lesions appear and feel on the skin. The most common variety is hyperkeratotic, which presents as thick, scaly, or wart-like growths, while the pigmented type appears as brown, freckle-like patches. Other forms include atrophic lesions, which look like thin, red sores, and actinic cheilitis, which specifically affects the lips, causing persistent dryness and cracking. Regardless of the specific appearance, all types require monitoring as they represent different visual manifestations of the same precancerous cell damage.

Xavier, living with Actinic Keratosis
Risk factors: actinic keratosis and sun exposure
Exposure to accumulated UV radiation over the years is mostly responsible for the development of actinic keratosis hence, this is why it occurs most commonly in older people. This accumulation results from sunbathing, from using tanning beds or from working or playing sports outdoors.
It is true that, while sunbathing affords certain beneficial effects—for instance, sunlight is necessary for the skin to produce vitamin D—excessive exposure to UV light causes mutations in the DNA of skin cells. This favors premature photoaging and the development of actinic keratosis and skin cancer.

Federico, living with Actinic Keratosis
How is it diagnosed?
Usually, a dermatologist will only need to examine the lesions to be able to diagnose actinic keratosis. Only when in doubt, the doctor will do a biopsy, which involves removing and sending off a sample of the lesion for microscopic examination in the laboratory.
What are the symptoms of actinic keratosis?
Actinic keratosis usually occurs in adults with fair skin in the form of rough, scaly spots, plaques or lumps. These spots can vary in color, can present as single or multiple lesions, and appear on sun-exposed areas. The surrounding skin may also be affected and look a different color or present small broken blood vessels. Even if it looks normal, this surrounding skin which is called field of cancerization can present alterations that can only be seen under a microscope.
Although actinic keratoses does not usually give any symptoms, they can sometimes cause itching or bleeding. You should always check with your doctor if you notice any of these symptoms.
References
- De Berker D, Mcgregor JM, Mohd Mustapa MF, Exton LS, Hughes BR. British Association of Dermatologists’ guidelines for the care of patients with actinic keratosis 2017. Br J Dermatol [Internet]. 2017 [cited 2020 Feb 19]; 176(1):20-43. Available at: https://onlinelibrary.wiley.com/doi/full/10.1111/bjd.15107
- BAD: British Association of Dermatologists. Actinic Keratoses - Also Known as Solar Keratoses [Internet]. London (United Kingdom): BAD; 2007 May [revised 2019 Nov; cited 2020 Feb 19]. 5 p. Available at: http://www.bad.org.uk/shared/get-file.ashx?id=66&itemtype=document
- Berman B, Cockerell CJ, Zografos P. Pathobiology of actinic keratosis: Ultravioletdependent keratinocyte proliferation. J Am Acad Dermatol [Internet]. 2013 Jan 1 [cited 2020 Feb 19];68(1 Suppl.1):S10–9. Available at: https://www.jaad.org/article/S0190-9622(12)01065-1/fulltext
- Moy RL. Clinical presentation of actinic keratoses and squamous cell carcinoma. J Am Acad Dermatol [Internet]. 2000 Jan [cited 2020 Feb 20];42(1 Suppl. 1):S8–10. Available at: https://www.jaad.org/article/S0190-9622(00)27494-X/fulltext
- Werner RN, Stockfleth E, Connolly SM, et al. Evidence- and consensus-based (S3) Guidelines for the Treatment of Actinic Keratosis - International League of Dermatological Societies in cooperation with the European Dermatology Forum – Short version [Internet]. J Eur Acad Dermatol Venereol. 2015;29(11):2069-79. Available at: http://doi.wiley.com/10.1111/jdv.13180
- Gohara M, Morison W, Sarnoff DS. Clothing: Our first line of defense [cited 2020 Feb 6]. Inn: The Skin Cancer Foundation [Internet]. New York (USA): The Skin Cancer Foundation; c2019. - [approx. 5 screens]. Available at: https://www.skincancer.org/skin-cancer-prevention/sun-protection/