What is solar lentiginosis?
Solar lentiginosis is a common dermatological condition that occurs mostly in white people over the age of 40. The condition involves the appearance of pale brown to dark brown spots on the skin called solar lentigines, liver spots, or age spots. Age spots are flat, usually oval areas of the skin that have increased pigmentation. In other words, they’re darker than the surrounding skin. They may be brown, black, or gray.
They’re most common on parts of the body that get regular sun exposure. This includes the:
- tops of the feet
- upper back
Although they can sometimes look like cancerous growths, age spots are harmless. However, treatments such as skin lightening or removal can be used for cosmetic purposes. The best way to prevent age spots is to avoid the sun and wear sunscreen.
What causes solar lentiginosis?
Ultraviolet (UV) light from the sun is the primary cause of age spots. The pigment that gives your skin color is called melanin. UV light speeds up the production of melanin, which results in darker skin, or a tan. After years of exposure to UV light, melanin builds up in certain areas and is produced in high concentrations. This results in age spots.
The UV light from tanning beds is from an artificial source but is otherwise no different from the natural light of the sun. The process of aging, regardless of UV exposure, also increases production of melanin and leads to age spots.
Some people may be more susceptible to the formation of age spots because of their genetic makeup. For example, you may be more likely to develop lentigines if you have fair skin and blonde hair.
Conditions that resemble solar lentiginosis
Solar lentigines are harmless. Some skin conditions that may resemble lentigines may be more serious, such as:
- melanoma, which is a malignant skin cancer
- keratosis, which is a noncancerous skin growth
- lentigo maligna, which is a type of skin cancer
See your doctor if you notice any of the following characteristics in your skin spots:
- very dark pigmentation
- an increase in size over a short period
- an irregular border
- itching, tenderness, bleeding, or redness
- a combination of colors
Diagnosing solar lentiginosis
Your dermatologist will begin with a visual inspection to diagnose solar lentigninosis and to rule out any other skin conditions. Dermatologists can usually identify age spots by looking at them.
If you or your doctor have any concerns or believe the spot on your skin may have a different cause, you may need a skin biopsy. This means that your doctor will take a small sample of skin from the area in question. You’ll receive a local anesthetic and your doctor will cut away a small piece of skin. They’ll send the sample to a lab for examination to determine if you have a condition other than solar lentiginosis.
Treatment for solar lentiginosis
Because age spots are harmless, treatment isn’t necessary. However, many people choose to treat age spots for cosmetic reasons. Topical medications are often less effective than physical procedures, but the latter can produce unwanted side effects.
Treatments include the following:
- Your dermatologist can prescribe bleaching creams to lighten age spots. These are often used with steroid and retinoid creams. Together, these medications can lighten your skin over time.
- Cryotherapy involves using liquid nitrogen to freeze the skin of the age spot. This can destroy the melanin that is producing the dark color. There is a small risk of scarring with cryotherapy.
- Dermabrasion involves using a rotating brush to scour your skin and remove its surface layers. You may experience redness and scabbing from this procedure.
Using a laser on age spots can destroy the cells that are producing melanin. This treatment requires several visits and will cause the age spots to fade over the course of several weeks or months. Laser therapy has no side effects if it’s done correctly. This is the most costly removal technique.
A chemical peel involves applying acid to your skin to dissolve its outer layers. New skin forms where the layers were destroyed. You need to have the treatment several times to see results. Irritation from it can be mild to severe. You should protect your skin from the sun immediately after the treatment.
Preventing solar lentiginosis
The best way to prevent the formation of age spots is to avoid exposure to the sun and tanning beds. Use sunscreen that provides protection from both types of UV light, UVA and UVB. Cover yourself with a hat, sunglasses, and clothing when you’re in the sun.
Solar lentiginosis is a harmless skin condition that often occurs with aging. No treatment is necessary from a health perspective, but you may want to treat it for cosmetic reasons. If so, various medications and therapies are available. You can discuss them with your doctor. You can help prevent age spots by always using sunscreen and covering yourself with a hat, sunglasses, and clothing when you’re in the sun.