FAQ about Angel's Nevus

What is a congenital melanocytic nevus?
Nevus (also spelled naevus; plural nevi) in the broad sense, means birthmark. There are several types of nevi: epidermal, melanocytic and connective tissue nevi. Melanocytic means that it is pigment-based. Congenital means it is present at birth. Nevus Outreach deals with large and giant congenital melanocytic nevi.

Nevi are the most common abnormality of the skin. They apparently serve no function. Normally, skin gets its color from melanin, which is produced by cells called melanocytes. Melanin is human pigment. Normally, melanin is distributed fairly evenly throughout the skin. Congenital melanocytic nevi, on the other hand, are made up of pigment-producing cells called nevomelanocytes. These cells are not evenly distributed. When many nevomelanocytes are clumped together, they can result in moles on the skin because of the higher concentration of melanin (pigment).

How common are congenital nevi?
Small melanocytic nevi are very common. One in every 50 to 100 people is born with a small melanocytic nevus. Large congenital nevi occur approximately once in every 20,000 births. Giant congenital nevi are thought to occur approximately once in every 500,000 births.

How is nevus-skin different?
Nevi are much more than simply dark skin. Besides producing increased pigmentation, the area covered by a melanocytic nevus often produces increased amounts of hair. The formation of sweat glands can be disrupted in nevi – so sometimes a person with a large nevus may not sweat where their nevus is located. Many nevi lack subcutaneous fat, a layer of fat just under the skin that pads the body everywhere. Some nevi will also have neurofibromas or other neural tumors, within their borders. These growths are not painful and are normally superficial. Nevus-skin can range from thick with a folded appearance, to thin and fragile. People with nevi sometimes complain that their nevus itches more often than the surrounding skin.

What causes nevi?
Large congenital nevi form in the womb very early in development, within the first twelve weeks of pregnancy. They are caused by a defect during embryologic development. There is no known method of prevention. They appear in either sex, in all races, and on any areas of the skin.

Can nevi pose a health problem?
Having a large nevus can impact one’s mental health. Large nevi are obvious and unusual. These can be difficult hurdles to overcome.

In terms of physical health, pigmented moles have been linked to melanoma, a potentially deadly skin cancer. Also, certain children with large nevi may have melanin, melanocytes and/or nevomelanocytes in their central nervous systems (the brain and spinal cord). This condition is known as neurocutaneous melanocytosis (melanosis) (NCM). Most people with NCM do not have neurological problems. However, some do, and the complications from NCM can be very serious.

Which moles may develop melanoma?
Scientific opinions vary as to the exact risk of melanoma, but current research may show the number of children born with large nevi who develop melanoma later in life to be around 5%. Any congenital nevus, small or large, may develop melanoma, but those of greatest concern are very large or thick.

Why remove a nevus?
Most of the time, the overriding reasons to remove a nevus are first to reduce melanoma risk and second to improve appearance which can be fundamental to improving a patient’s overall psychosocial state. Other reasons to remove a nevus may be to improve the strength, texture, sensation, and sweat gland activity of the affected area.

While it is almost impossible to remove every cell of a large nevus, the goal is to remove as many cells as possible while at the same time preserving function and minimizing scarring. Remember, a nevus cannot be removed without leaving a scar.

Some people choose to leave their nevi intact, while others choose to remove them. There are good reasons for both choices. It is a highly personal decision.

If you would like to learn more please visit: http://www.nevus.org/index.php

More to come regarding our plans.