Childhood melanoma different from that of adults

Experts are calling on physicians who care for children to be alert to the possibility that unexplained lesions could be melanoma because of growing evidence that skin cancer is increasing in all age groups and that it might progress differently in younger patients.

"If a parent says something has changed or doesn't look right, it should be considered for further work-up," said Lynne Lillie, MD, a family physician with HealthEast Clinic in Woodbury, Minn. "And parents should be encouraged to bring up the issue to a physician."

Recently, a study in the March issue of Pediatrics suggested that melanoma in those younger than 14 is more likely to lack pigmentation, and the illness is more likely to be diagnosed at a later stage when lesions are thicker. This finding did not translate into increased mortality, and the authors of this study and an accompanying editorial are calling for increased alertness, although not necessarily more screening.

"We should avoid alarmism," said Andrea Ferrari, MD, lead author on the paper and a researcher with the Istituto Nazionale Tumori, Milan, Italy. "Primary care physicians must be aware that melanoma can occur in childhood and be able to send suspected patients to colleagues who could help in early diagnosis."

Experts widely praised the paper for providing some insight into what is a rare but increasing cancer and agreed that changes to screening recommendations were not necessary.

The U.S. Preventive Services Task Force guidelines currently say there is insufficient evidence to recommend for or against total body skin examinations, although the American Cancer Society recommends one every three years for those ages 20 to 39. Annual skin checks are recommended for those older than 40, but there are no specific recommendations for those younger than 20.

"It's hard to advocate for screening because it's so rare," said John Strouse, MD, a pediatrics instructor at Johns Hopkins University School of Medicine in Baltimore. "How many people do you have to screen to detect a case? You'd have to take off a lot of moles to find a melanoma."

But while experts said screening recommendations did not need to change, this study did highlight the importance of physicians advising young patients about sun safety to prevent skin cancer in their lifetimes, particularly for those at higher risk. For example, a study presented at the American Society of Clinical Oncology's annual meeting in June 2004 found that, in the pediatric population, melanoma was more likely to strike those who were white and female.

"One of most important messages is that melanoma, while rare in children, is not really rarer than other cancers we worry about in children," said Dr. Strouse, lead author on that paper. "The focus should be on prevention, particularly in fair-skinned patients. Decrease UV exposure in childhood and you reduce melanoma in all ages."

Experts did say, however, that this study had serious limitations. The study looked at only 33 patients at a single center. This small study population could lead to referral bias, and the numbers are not sufficient to prove conclusively that childhood melanoma is that different from its adult variant.

"It's an interesting paper for raising the questions it does, but ultimately it's still premature to say for sure that there is a clear-cut difference in the behavior or presentation of childhood versus adult melanoma," said Anthony Jerant, MD, associate professor in the Dept. of Family and Community Medicine at the University of California, Davis. "One would need a much larger, population-based study to begin to really sort this out."

Those who work with childhood melanoma patients also said that because this cancer is rare, statistical significance might never be achieved.

"It's hard to prove anything with childhood melanoma," said Eric Mooney, MD, PhD, assistant professor and plastic surgeon at Bassett Healthcare in Cooperstown, N.Y.