What are the other Names for this Condition? (Also known as/Synonyms)

• Liver Spot
• Old Age Spot
• Sun-Induced Freckle

What is Solar Lentigo? (Definition/Background Information)

• Solar Lentigo is a common benign condition characterized by dark skin spots on the face and back of the hands, which develops in middle-aged and older adults typically following exposure to long-term sunlight (ultraviolet radiation)
• Solar Lentigo is also known as Old Age Spot. The skin spots are typically asymptomatic but can remain persistent. In some cases, they may be mistaken for a melanoma, which is a malignant skin condition
• Solar Lentigo may be treated for cosmetic purposes and this may involve cryotherapy or laser surgery. The prognosis of the condition is generally excellent with suitable treatment. Avoiding prolonged sun exposure and using sun protection creams may help decrease the onset risk of new lesions

Solar Lentigo is also referred to as a Liver Spot. The term ‘Liver Spot’ does not indicate medical problems with the liver of the patient. It simply refers to a mild similarity of the color of the lesion to animal livers.

Who gets Solar Lentigo? (Age and Sex Distribution)

• Solar Lentigo are very common skin lesions generally observed in adults over 40 years of age. The condition is infrequently noted in children
• Both males and females are affected
• Worldwide, there is no racial or ethnic preference observed. However, individuals living in latitudes around the tropical regions and those in higher altitudes, may be at an increased risk for the condition

What are the Risk Factors for Solar Lentigo? (Predisposing Factors)

The risk factors for Solar Lentigo include:

• Chronic sun exposure: Exposure to sun for a long period (usually decades)
• People living in tropical or subtropical geographical regions
• People living at higher altitudes
• Individuals who are more prone to sunburns, and those that do not tan easily
• Exposure to artificial ultraviolet light sources

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Solar Lentigo? (Etiology)

• Solar Lentigo (plural lentigines) is caused from prolonged exposure to the sun’s ultraviolet (UV) radiation for many years
• This causes melanin pigment to accumulate in skin cells from local proliferation of melanocytes (melanin-producing cells)

What are the Signs and Symptoms of Solar Lentigo?

The signs and symptoms of Solar Lentigo may include:

• Presence of a single or multiple dark skin spots
• The skin spots are flat and generally well-defined with clear borders. They may be circular, oval, or irregular in shape
• The size of the spots vary from a few millimeters to several centimeters
• The skin lesions are predominantly seen on sun-exposed surfaces such as the face and neck region, shoulders and upper chest/back, hands/arms, and lower legs (including the feet)
• In individuals treated with ultraviolet radiation therapy, the spots may be seen at the treated skin areas
• The skin lesions may be black, brown, or even skin-colored; the lesions appear generally dry
• In some individuals, slight scaling is noted around the lesions
• Individuals of both light and dark colored skin may present Solar Lentigo
• There is no pain, itching, or burning sensation observed; also, the lesions are non-inflammatory

How is Solar Lentigo Diagnosed?

A diagnosis of Solar Lentigo may involve the following exams and procedures:

• Physical examination of the skin (lesion) and medical history evaluation, including history of one’s work/occupation. This is usually sufficient to arrive at a diagnosis
• Dermoscopy: Dermoscopy is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Skin biopsy (if needed): A skin tissue biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

Atypical Solar Lentigo may be confused with melanoma, which is a malignant skin condition that generally arises from increased exposure to UV rays. In such cases, a skin biopsy may be requested by the healthcare provider to clarify the suspicion.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Solar Lentigo?

The possible complications due to Solar Lentigo include:

• Emotional stress due to cosmetic issues
• Irregularly appearing skin spots may be mistaken for melanoma (a form of skin cancer) causing anxiety in the affected individual
• There is an increased risk for seborrheic keratosis arising from Solar Lentigines. Seborrheic keratosis is a benign skin condition causing localized skin texture changes and thickening of skin
• Treatment complications

How is Solar Lentigo Treated?

In many individuals, treatment for Solar Lentigo may not be necessary unless there are cosmetic concerns. The treatment measures available include:

• Lifestyle changes that includes spending less time in the sun
• Application of topical sun protection creams (oil-free sunscreens)
• Use of moisturizing creams for dry skin
• Cryotherapy (cold therapy)
• Laser therapy (laser surgery)
• Use of bleaching creams containing hydroquinone; this is not known to be effective in many cases

Regular follow up visits with the healthcare provider may be recommended.

How can Solar Lentigo be Prevented?

In general, it may not be possible to prevent the development of Solar Lentigo. However, the following measures may be considered to lower one’s risk for the same:

• Avoiding prolonged and chronic exposure to the sun
• If this is unavoidable (like due to an occupational requirement), then taking safety steps to reduce exposure to the UV rays, such as by using sunscreens with high sun-protection factor, wide-brimmed hats, and protective clothing
• Being aware of the hazards of prolonged sun exposure and taking steps to protect oneself. Modifying one’s profession to stay out of the sun during the period when it is most intense
• Keeping oneself well-hydrated if sun-exposure for prolonged periods is unavoidable

What is the Prognosis of Solar Lentigo? (Outcomes/Resolutions)

The prognosis of Solar Lentigo is generally excellent with adequate treatment. The condition is typically benign and non-inflammatory.

• Even though benign and harmless, in the absence of any treatment, Solar Lentigo may persist throughout one’s life
• Occasionally, the skin spots may become inflamed (a condition termed lichenoid keratoses) and then gradually disappear
• Solar Lentigo is not an indication that the individual is at a greater risk for skin cancer

Additional and Relevant Useful Information for Solar Lentigo:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/skin-disorders/