Porokeratosis is an uncommon type of skin condition characterized by scaly, discolored, dry specks or patches on certain parts of the body. Most cases are related to genetic disorders and present in childhood, though some people develop symptoms later in life due to ultraviolet radiation, excess sun exposure, or unidentified causes. The condition does not usually cause major health problems, though there are increased risks of developing skin cancer if multiple lesions are present on the body. People can lower their risks by protecting their skin, using topical medications, and keeping frequent appointments with their dermatologists to track any changes in their skin.
Most forms of this condition are inherited in an autosomal dominant pattern. A child is susceptible if one of his or her parents carries a particular genetic mutation. Researchers have not yet identified the specific genes, though studies are ongoing to better understand the genetics involved. Occasionally, a middle-aged or elderly person can develop the condition on sun-exposed areas of skin. Exposure to medical radiation and artificial ultraviolet light, such as the type used in tanning beds, is also correlated with porokeratosis.
The symptoms can vary widely. Some people develop very small, raised, ring-shaped lesions that are tinted red or brown. Others have larger light-colored patches on their arms, legs, hands, or feet. It is possible to have a single lesion or multiple abnormal spots on the body. Lesions typically do not change in size and shape over time, and any changes that do occur can be signs of developing skin cancer.
Skin carcinomas that arise due to porokeratosis are usually characterized by hard, scaly, dark-colored lesions. As a malignancy grows and spreads, a person may develop other symptoms, such as fatigue and fever. Early recognition and treatment of cancerous lesions is essential to prevent metastasis and life-threatening complications.
Noncancerous porokeratosis does not normally require aggressive treatment. Doctors typically suggest that their patients attend checkups at least once a year to check for signs of abnormal growth. It is important for patients to wear sunscreen and protective clothing when going outdoors regardless of the weather, and to avoid artificial radiation exposure to the best of their abilities. Topical creams, such as fluorouracil, are occasionally prescribed to improve the appearance of porokeratosis lesions, but this type of treatment only rarely leads to complete remission. If the condition becomes malignant, a combination of surgery and chemotherapy may be necessary to reduce the risks of further health problems.