Giant Congenital Nevi

Sometimes a birthmark, or nevus (plural nevi), is dark-colored and covers a large portion of a newborn’s body. It begins forming in utero and is usually visible when a baby is born.

These patches of skin may be light brown in fair-skinned children and may be almost black in darker-skinned children. They’re sometimes raised and hairy. They occur most often on the trunk but are also common on the arms and legs and the head/scalp and neck. When it covers more than 2% of a patient’s total body surface area, or if it is larger than the palm of a child’s hand, it is considered a giant nevus.

A giant nevus is usually accompanied by several additional smaller nevi, called satellites. When a child is born with a giant nevus, it is common for satellite nevi to be present at birth.

There is a small chance that dark-colored nevi can turn into skin cancer, or melanoma, over time. They can also grow internally and lead to a condition called neurocutaneous melanosis, which affects the nervous system and can be associated with seizures and increased pressure inside the skull, leading to headaches and visual loss. Early treatment of giant congenital nevi lowers the risk of skin cancer and other conditions.

Without treatment, the nevi grow as the child grows. The nevi may develop coarse hair when a child is 1-2 years of age and continue to become darker as a child ages.

At Lurie Children’s, plastic and reconstructive surgeons who specialize in treating this condition can guide families to the best treatment options, which may be include regular monitoring of the nevus, and/or surgical removal.

How Are Giant Congenital Nevi Diagnosed?

Congenital nevi are often visible at birth, appearing hairless, flat and pal brown.

Giant nevi occur in an estimated 1 in 20,000 births.

Plastic and reconstructive surgeons, along with input from a dermatologist early on, can determine whether a giant congenital nevus is present, and provide a treatment plan. Getting a treatment plan for a child planned and executed as early in life as possible helps ensure the best outcomes. In some cases, surgical options can begin for children as young as six months of age so that they can be finished with treatment by the time they begin school.

How Do We Treat Giant Congenital Nevi?

Tissue Expansion

If the nevus is small enough, it can be removed in stages, usually through surgeries. Sometimes the child’s skin can be closed over the nevus surgically, but in cases where the nevus is very large, a child’s skin can be grown to replace the nevus. 

Tissue expansion often provides the best outcomes in terms of appearance and function for patients with giant congenital nevi. Tissue expansion is a common effective way of developing more skin or tissue to cover the area from which the nevus will be removed. In this procedure, the skin and soft tissues near the giant nevus are stretched to grow new skin. If tissue expansion is performed, a balloon — called an expander — is placed under the child’s skin, typically near the nevus so that a flap of skin can be created. Over a period of one to three months, the expander is filled with more and more liquid to gradually stretch the skin around it. When enough extra skin has been created, the tissue expansion is complete, and the new flap of skin is used to replace the nearby nevus.

By using a child’s own skin to reconstruct the location of a nevus, this tissue expansion often provides new skin with nearly matching color, texture and other qualities of the rest of the child’s skin.

Tissue expansion can be done practically anywhere on the body, and the child’s doctor will determine the best area for the expander balloon to be placed. Some common areas for tissue expansion are in the thigh, back, abdomen and scalp. Many patients report being able to maintain their routine and activities with the expanders in place.

Skin Grafts & Alternative Methods

There are ways other than tissue expansion to resurface the giant nevus. Some of these include skin grafts taken from an area not near the nevus, flaps of tissue transferred from nearby areas or microvascular transfer of skin and tissues from other parts of the body. However, these techniques are often compromised in their ability to match the skin to be replaced, particularly in the face. This is an advantage of tissue expansion, since it relies on stretching the skin adjacent to the nevus, which is the best match for the replacement skin.

There may also be nonsurgical treatments appropriate for the child, including high intensity exfoliating techniques (dermabrasion), chemical peels and laser removal. However, these techniques only impact the appearance of the nevus, and do not decrease the risk of skin cancer arising from the giant nevus.

Removing the nevus often requires multiple stages and sometimes different types of procedures. The best treatment options for a child depend on the location of the nevus, the child’s age, medical history and other variables.

Lurie Children’s staff will help educate families about the benefits and risks of each procedure and why it may be appropriate for the child. When necessary, staff will also help families understand how to properly care for a child’s wound and scar from the surgical site after they go home.

A doctor will discuss all the possible options to determine which method will be the best and most comfortable for the child, who is likely to experience improved appearance and a decreased risk of complications from the nevi.

At Lurie Children’s, physicians, nurses, a social worker and a family life specialist will work with families to prepare a comprehensive plan for the child and then ensure the plan is carried through.

What Is Recovery Like After Surgery for Giant Congenital Nevi?

For many patients, procedures for treating giant congenital nevi will occur on an outpatient basis, but length of stay in the hospital and potential side effects and complications will depend on the type of treatment a child needs.

When sutures, or stitches, are necessary, surgeons in many cases are able to use absorbable sutures, eliminating the need for families to return the hospital to get them removed.

Dark patches of skin can appear around the surgical scars, and in some cases can be removed, but families should discuss with doctors whether this is necessary and appropriate.

More severe complications, such as infection, can delay reconstruction of the site, but doctors will monitor postoperative patients to keep this from happening as much as possible.

For the tissue expansion procedure, patients who had expanders over a large part of their body may need to stay in the hospital overnight for monitoring when the sutures are removed. Many patients will be prescribed antibiotics for the first week post-surgery to prevent infection at the site of expansion, and all patients will be monitored regularly on an outpatient basis after surgery.

There can be side effects and complications with tissue expansion. Common side effects of tissue expansion surgery include pain, a buildup of fluid at the site of tissue expansion, bruising of the expanded skin and rupture of the expander. In many cases, doctors can help make a patient more comfortable should they endure any side effects.  By working closely with the team at Lurie Children’s, almost all of these side effects and complications can be overcome.

What Are the Outcomes After Surgery for Giant Congenital Nevi?

Early surgical treatment for giant congenital nevi most often lead to improved appearance, more resilient skin that is less prone to ulceration and breakdown, and decreased risks of skin cancer and other conditions related to giant nevi.

Many patients with giant congenital nevi will require lifelong outpatient follow-up care following any surgeries they endured, but they face few, if any, limitations following surgery and postoperative care.


Dr. Arun K. Gosain leads the Lurie Children’s Division of Plastic and Reconstructive Surgery and is an expert in the congenital nevus removal and treatment. Congenital nevi are one of his main clinical interests.

To make an appointment with Dr. Gosain and the plastic and reconstructive surgical team, call 1.800.543.7362 (1.800.KIDS.DOC).

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