While melanoma in children is still extremely rare, the rate increased by about 2 percent per year from 1973 to 2009 among US children from newborns to age 19. Melanoma accounts for up to 3% of all pediatric cancers, according to the Skin Cancer Foundation.
According to the study, 1 317 children were diagnosed with melanoma during the study time frame. Of these, 1 230 children were white. Because the number of melanoma cases among other racial and ethnic groups was so small, researchers focused the analysis on white children.
The biggest jump in melanoma rates was seen among adolescents aged 15 to 19, especially girls, the study showed.
Recent studies have also shown that melanoma is on the rise among adults as well. Exactly what is driving these trends is not fully understood, but increased exposure to ultraviolet radiation from both the sun and tanning booths as well as greater awareness of melanoma may be responsible, according to study authors led by Jeannette Wong of the US National Cancer Institute.
What the study found
The researchers used a database to capture trends in childhood melanoma, but they did not have any information on participants' tanning habits or sun exposure history.
Boys were more likely to develop melanomas on their face and trunks, while girls were more likely to have melanoma on their lower legs and hips, the investigators found.
Other risks for melanoma among children and adults include fair skin, light-colored hair and eyes, moles, family history of melanoma and a history of sunburns.
Dr Amy Forman Taub, a dermatologist in Lincolnshire, Ill., said that tanning behaviors have a lot to do with the increasing rates of melanoma in children and adults.
"It's the tanning booths and the fact that we go away on vacation where we are exposed to a lot of intense sun," she said.
Genes may also play a role, suggested Taub, who was not involved in the new study.
Melanoma in kids looks pretty similar to melanoma in adults, Taub said. They have irregular borders, are asymmetrical - if you cut them in half, you would not get two equal sides - have uneven colors, and a diameter that is greater than 6 millimeters (about one-fifth of an inch).
"Parents should be aware of any new or changing moles in their children," she advised.
Choosing a sunscreen that blocks both ultraviolet A and ultraviolet B rays and reapplying it frequently is important, she said. Sun-smart clothing can also help protect children.
Dr Ana Duarte, director of pediatric dermatology at Miami Children's Hospital, agreed.
"Early diagnosis of melanoma is beneficial," she said, and the importance of protection can't be overstated. "Sunscreen and or sun protection are so important for children," Duarte said, and whatever you do, "don't ignore changing moles, even in children, because melanoma can occur in kids."
Dr Michele Green, a dermatologist at Lenox Hill Hospital in New York City, said the new study puts childhood melanoma on the radar, and that's a good thing.
"It is rare, but children do get melanoma," Green said. "When in doubt, get it checked out. The good news is that we know how to prevent melanoma, and when we catch it early, we have really good cure rates."
What does melanoma look like? Find out at the Skin Cancer Foundation.