Lentigo is a common type of skin spot that has a dark color and a defined edge. It can be found on any part of your body and is most often caused by sun damage or exposure to radiation. There are numerous types of lentigo, but the most common type is called lentigo simplex.

Unlike other types of lentigo, lentigo simplex isn’t caused by skin damage. The cause is still unknown, but it usually develops between birth and early adulthood. Unlike many other types of skin spots, lentigo simplex doesn’t get worse or change color when exposed to sunlight.

In this article, we’re going to examine how lentigo simplex differs from other types of skin spots. We’ll also look at causes and potential treatment options.

Lentigo simplex can occur anywhere on your limbs, body, or mucous membranes. Unlike other types of lentigo, lentigo simplex can appear at birth or in childhood. The spots don’t cause pain or itchiness and are benign, meaning that they don’t develop into skin cancer.

Lentigo simplex spots usually have these characteristics:

  • round or oval shape
  • 3-15 mm in diameter
  • dark brown or black color
  • jagged or smooth edge

Lentigo simplex spots may occasionally be mistaken for freckles. However, unlike freckles, lentigo simplex spots don’t change color when exposed to sunlight. They also aren’t generally found in clusters.

It’s not clear at this time what causes lentigo simplex. Lentigo simplex is also not linked to any other medical conditions. It most commonly appears from birth to early adulthood.

There are no known risk factors for developing lentigo simplex. The primary risk factors for other types of lentigo include:

Lentigo simplex vs. melanoma

Melanoma is a type of skin cancer that occurs in the cells that give your skin its color. It’s caused by exposure to ultraviolet radiation from either sunlight or tanning beds.

Both lentigo simplex and melanoma can arise on any part of your body. Melanoma most often appears on parts of your body that receive frequent skin exposure such as your face. Ways that lentigo simplex and melanoma appear different include:

  • Shape. Lentigo simplex usually has a round shape while melanoma has an irregular shape.
  • Edges. Lentigo simplex can have smooth or jagged edges. Melanoma often has an irregular edge or pigment that fades into the skin around it.
  • Color. Lentigo simplex has a uniform dark brown or black color. Melanoma can have shades of tan, black, or brown. It may even have areas that look white, gray, red, blue, or even pink.
  • Size. Lentigo simplex is usually between 3-15 mm across. Most melanoma spots are wider than 6 mm, or the size of a pea.
  • Change. Lentigo simplex stays the same size while melanoma grows over weeks or months.

If you have a concerning skin spot, you can use this A-B-C-D-E guide to help determine if it may be melanoma. Answering yes to any of the following questions may mean your spot is melanoma.

  • A – Asymmetrical. Does the spot have an irregular shape?
  • B – Border. Does your skin spot have a jagged border?
  • C – Color. Does it have an uneven color?
  • D – Diameter. Is it larger than a pea?
  • E – Evolving. Has the spot gotten bigger over the past few weeks or months?

Even if you don’t think your skin spot is cancerous, it’s a good idea to have a doctor check it to be safe.

Lentigo simplex doesn’t usually cause pain or itchiness. The spots are also non-cancerous, but they can resemble other types of spots that can be cancerous. It’s a good idea to get them checked out by a dermatologist. Several tools can be used to remove the spots for cosmetic reasons including the following:

Chemical peels

A chemical peel is used to removed damaged skin cells on your hands, face, or neck. During a chemical peel, a chemical solution is applied to your lentigo. The chemicals exfoliate your skin spot to uncover healthy skin underneath.

Cryotherapy

Cryotherapy is a method of freezing your skin spot with liquid nitrogen. It’s used for abnormal skin spots that are non-cancerous or precancerous. The treatment takes up to 10 days to heal from and usually doesn’t leave a scar.

Laser therapy

Laser therapy involves using beams of light to remove your lentigo skin spot. Laster therapy allows for a more precise removal than with traditional surgery. Many people who undergo laser surgery also have quicker recovery times.

Lentigo is usually classified based on the cause and location on your body. Most types of lentigo are caused by sun or radiation exposure. Lentigo is most common in middle-aged or older people.

  • Solar lentigo is caused by sun exposure and is often referred to as age spots or liver spots. Solar lentigo commonly appears in sun-exposed parts of your body. The majority of older adults have solar lentigo.
  • Ink spot lentigo is a black and irregularly shaped spot that occurs after a sunburn in people with light skin.
  • PUVA lentigo looks similar to ink spot lentigo but occurs after photochemotherapy.
  • Tanning bed lentigo looks similar to ink spot and PUVA lentigo but is caused from tanning bed radiation.
  • Radiation lentigo is caused by exposure to either accidental or intentional radiation. Certain cancer therapies may lead to this type of lentigo.

Lentigo simplex is the most common type of lentigo. Lentigo simplex spots are usually round or circular and have a dark brown or black color. It’s not clear what causes these spots, but they usually appear between birth and early adulthood.

You can protect yourself from other forms of lentigo by minimizing unprotected sun exposure and use of tanning beds. Even though lentigo simplex isn’t serious, it’s a good idea to get all your skin spots examined by a medical professional to rule out other more serious skin conditions.