Moles, clinically called nevi, are present in about 1% of newborns, while the average adult has 10-40 moles. Therefore, moles must grow during childhood. Pediatric moles are generally harmless. They continue to appear throughout childhood and adolescence and they may grow as the body grows. They may also naturally darken, lighten or even fade away completely. Because of this the ABCDE’s of moles can’t completely apply. It’s important to know how normal childhood moles present. You can’t know what to worry about if you don’t first know what’s normal.
Normal Pediatric Nevi
Statistically melanoma is rare in children. However, since melanomas that are diagnosed early are more easily treated, it’s important to seek the advice of your dermatologist for suspicious nevi. The most common suspects parents bring their children in for are new moles, moles that become raised or grow in size, and ones that grow hair. More often than not, these are normal occurrences in children.
Children generally have “signature nevus”, meaning their moles present in their own style as they appear. The globular pattern is the most common, especially when found on the trunk of the body. Raised does not indicate malignancy.
Two-toned nevi, such as the eclipse, target/cockade, and fried egg types, are common and normal especially amongst caucasian children. These moles often arise on the scalp in the first few years of life. Scalp nevi often make parents nervous because they aren’t always caught early so their size may come as a surprise.
Acral nevi appear on the hands and feet and often look different and worrisome. These moles are characterized by lesions that are macular or slightly elevated, and may display linear striation of brown color. While they are different, they are completely normal.
Genital nevi are also normal. In a study of 1159 children, the prevalence of gental moles was 3.5% with a male:female ratio of 1.3:1. 93% of these cases displayed globular nevi and a gradual change in diameter, elevation, color and texture was observed in most. There were no melanoma or other adverse outcomes during follow-up.
Spitz nevus is an abruptive pink papule common in young children. They are benign but under a microscope it is sometimes hard to differentiate a Spitz nevus from melanoma. Atypical Spitz nevus is more worrisome. The differences between Atypical Spitz nevi and Spitz nevi are as follows:
- 10-20 year olds vs. under 10 years old
- Present on the back vs face, extrem, neck
- Over 10mm vs under 5 mm
- Irregular and asymmetrical vs symmetrical
- Family history vs none
Pigmented Spitz nevi are most commonly found on arms and legs and are more common in people with darker skin. While also appearing worrisome, they are benign.
Nail nevi often presents a challenge. Moles are a common cause of longitudinal melanonychia of a single name in a child. While often confused with Hutchinson’s sign, nail matrix nevi in children is a pseudo-Hutchinson’s sign and is not malignant. Hutchinson’s sign is a nail melanoma with pigmentation that extends to the skin surrounding the nail and is not common in children. Nail matrix biopsies are difficult as they look very different compared to skin biopsies.
How To Identify What’s Not Normal?
While melanoma is rare in children, there are times when a mole needs to be checked by a dermatologist. According to the American Academy of Dermatology Association, following symptoms in moles are not normal:
- Changing mole: while it is normal for a mole to grow at the same rate as the child, if it grows rapidly or changes color abnormally, this may be worrisome. If a mole looks different from other moles on the body, this may be an “ugly duckling” and needs to be checked by a dermatologist.
- Dome-shaped mole with different colors and has a jagged border: While a Spitz nevus is harmless, it can look a lot like melanoma. Both a Spitz nevus and melanoma can bleed, break open, or be dome-shaped. Both can have more than one color. These spots need to be examined and either removed or watched closely by a professional.
- Bleeding mole: While it is possible for moles to become irritated and bleed, if it is bleeding without reason, it needs to be checked. Bleeding and looking like an open sore are not signs of healthy moles.
- Multiple moles: If your child has over 50 moles, it is important to seek out dermatological care. Having many moles may be an indication of being more at risk for melanoma.
- Large moles: Large congenital moles are generally not malignant. However, having large or giant moles may increase the risk of developing melanomas.
Moles that are considered risky may need to be biopsied. Excisional biopsy should be used in the cases where a lesion is suspicious.
Congenital Nevi and The Associated Risks
Congenital nevi come in all different sizes – small, medium and large/giant. The average congenital nevus presents little to no risk to the child but giant congenital nevi may be difficult to follow due to nodules.
Giant congenital melanocytic nevus is characterized by an abnormally dark skin patch (nevus) and is generally benign. It is composed of melanocytes, the cells producing the pigment in our skin. Congenital refers to nevi that are present at birth or noticed soon after. While congenital melanocytic nevus appear small in babies, they grow at the same rate the body grows. Giant congenital nevus are often found on the trunk or limbs, but may appear anywhere on the body. Coloring ranges from tan to black and often changes lighter or darker over time. It is possible for the surface of giant congenital melanocytic nevi to be raised, thickened, rough, bumpy or flat and may also change with time. The skin of the nevus is prone to itching and irritation. Hypertrichosis (excessive hair growth) can occur on the nevus, but is not worrisome. Additional nevi may be scattered on the skin.
Giant congenital melanocytic nevus can sometimes be associated with neurocutaneous melanosis. This occurs when pigment producing cells appear on the brain and spinal cord as clusters. These growths can increase the pressure in our brain leading to vomiting, headache, seizures (fits) and movement problems. Additional risk of giant congenital melanocytic nevus is melanoma. Research has found that there is an added 5-10% lifetime risk of developing melanoma.
Children with giant congenital nevi with a risk of neurocutaneous melanosis should have a brain/spine MRI before 4 months of age for a baseline. A pediatric neurologist should be consulted if the MRI is abnormal. Parents and pediatricians should be aware of potential neurological complications. Surgery is also an option for cosmesis, worrisome areas.
Who Needs Routine Screening?
Not all childhood moles need routine screening. Children with an immediate family member with melanoma, multiple nevi, irregular nevi, have red hair, fair skin with freckles and burn easily, or a history of Spitz nevus, should have an annual exam. If aesthetics are a factor for congenital nevi, it is important to consult with a plastic surgeon.
Given the extreme rarity of pre-puberty melanoma makes little sense for most. While melanoma can arise within a mole, moreso moles are a precursor to melanoma. For that reason, we don’t cut out most moles. The practice of “cutting off the worst mole” at each visit is not medically sound. Generally if it looks like a mole, it is a mole!