Melanoma is a type of skin cancer that is caused by melanocytes, a type of pigment-producing cell in the body. The term “childhood melanoma” refers to cases of this cancer diagnosed in patients under the age of 18. While rare, this type of cancer can be dangerous if not promptly treated.
Types of Childhood Melanoma
There are six types of melanoma that arise in children. These include:
- Melanoma development in brown birthmarks, also known as congenital melanocytic naevus.
- Congenital melanoma, which is present at birth.
- Blue naevus, which is malignant.
- Melanoma in patients with atypical or dysplastic naevi.
- Spitzoid melanoma.
- Nodular melanoma (accounts for 40%-50% of malignant childhood melanoma cases)
Signs and Symptoms of Childhood Melanoma
The signs and symptoms of melanoma in children vary depending on the child’s age. Older children, for example, will present symptoms very similar to adults. Younger children, on the other hand, exhibit unique symptoms.
In order children, aged 11-18, melanoma appears as a growing lesion, typically pigmented. Typically, the lesion has irregular borders, is asymmetrical, varies in color, is evolving and has a diameter of less than 6 mm.
For children aged 10 and younger, melanoma is more likely to be red in color (known as “amelanotic”), thick and nodular. In this age bracket, the lesion may appear as a bump and may bleed. The color is not uniform and may be any size.
Children born with birthmarks are more likely to develop melanoma, but still, cases are rare when the birthmark is small or medium in size. However, children born with large birthmarks (greater than 40 cm in diameter) have a 4% risk of developing melanoma. Birthmarks of this size are very rare and only occur in 1 in 20,000 births.
Who is at risk for Childhood Melanoma?
Melanoma is rare in children, and exceptionally rare before puberty. Of all pediatric cancers, it accounts for just 3% of cases. Common risk factors for this type of cancer include:
- Immunodeficiency
- Dysplastic naevus syndrome
- Fair skin that burns easily and freckles
- Multiple moles
- History of the eye cancer retinoblastoma
- Xeroderma pigmentosum
While typically caused by sun exposure, there is a growing body of evidence that suggests melanoma can also arise from exposure to laser devices, like those used for laser hair removal. With at-home devices now available, children may be at greater risk of accidental exposure.
How is Melanoma in Children Treated?
The treatment for melanoma in children is similar to those used in adults.
Typically, suspicious lesions are removed by an excision biopsy. If melanoma is confirmed in the lesion, a second procedure is performed, known as a wide local excision. This procedure removes a wider margin of the child’s normal skin. The amount of skin removed will be dependent on the thickness of the melanoma.
In cases of advanced melanoma, where the cancer has spread to the lymph nodes or another place in the body, treatment may include chemotherapy, radiotherapy, targeted therapy or surgery.
Prognosis of Childhood Melanoma
The outlook for children diagnosed with melanoma is largely dependent on the stage of the cancer. Thicker tumors are more likely to spread to other areas of the body, and may be more difficult to treat.
The survival rate of childhood melanoma is similar to survival rates in adults. Cases involving children under the age of 11 are an exception, as they tend to be less aggressive than cases involving older children and adults.