Solar Lentigo

Lentigines are a benign skin condition which may develop anywhere on the skin. The condition typically consists of hyperpigmented spots on the skin, which are usually flat and have a well-defined border. They are not usually accompanied by other symptoms.

The condition is divided into subtypes by appearance, cause, location, and association with other conditions. Lentigo simplex is the most common form of the condition. Spots develop at birth or during childhood, and the cause of this subtype is unknown. Solar lentigines develop on areas of the skin which are often exposed to sun, and are sometimes referred to as age or liver spots. Ink-spot lentigines present as solitary black spots, typically surrounded by solar lentigines. Ink-spot lentigines commonly affect those of Celtic heritage. PUVA lentigines develop in association with PUVA therapy, and appear similar to solar lentigines with a less well-defined border. Radiation lentigines are also similar in appearance to solar lentigines, but arise in association with radiation exposure, and may be accompanied by other skin conditions as a result. Tanning-bed lentigines result from the use of tanning beds, and may develop quickly or after a period of constant use. Oral and labial melanotic macules typically consist of a solitary lesions on the lower lip, mouth interior, gums, cheeks, and tongue, and may present in relation to an associated condition. Vulvar and penile lentigines develop on the genitalia, may be dark brown to tan in color, and their borders are irregular. Lentigines profusa has no associated conditions, and consists of many lesions appearing on the torso, extremities, genitalia and palms, which may coalesce into pigmented patches of skin. Agminated lentiginosis consists of many lesions which appear on a single part of the body, develops in young children, and is typically associated with other conditions. Syndrome-associated lentigines occur in conjunction with xeroderma pigmentosum, Peutz-Jeghers syndrome, Laugier-Hunziker syndrome, myxomas, and LEOPARD syndrome.

Differential Diagnosis (Other conditions with similar appearance)
Actinic Keratosis
Ephelides (Freckles)
Seborrheic Keratosis
Melanoma
Lentigo Maligna Melanoma

Lentigines are typically diagnosed based on the appearance of the affected area. Skin biopsies and other testing may be performed to rule out associated conditions.