AUSTIN – The compared with females. The risk of death is also significantly increased in black patients, other nonwhite patients, and in cases where surgery was not performed.
Those are key findings from a study that set out to investigate the incidence of pediatric melanoma over the last 2 decades and factors influencing survival. At the annual meeting of the Society for Pediatric Dermatology, one of the study authors, Spandana Maddukuri, said that pediatric melanoma is the most common skin cancer in the pediatric population, accounting for 1-3% of all pediatric malignancies and 1%-4% of all cases of melanoma ().
“Nonmodifiable risk factors are similar to those in adult melanoma and include fair skin, light hair and eye color, increased number of congenital nevi, and family history of melanoma,” said Ms. Maddukuri, a third-year student at New Jersey Medical School, Newark. “Environmental risk factors are similar to those in adult melanoma and include exposure to UV radiation. About 60% of children do not meet standard ABCDE [asymmetrical, border, color, diameter, evolving] diagnosis criteria, which often leads to delayed diagnosis.”
Some of the characteristics that are more commonly found in pediatric lesions include amelanosis, bleeding, uniform color, and variable diameter ().
Ms. Maddukuri and colleagues queried the National Cancer Institute Surveillance, Epidemiology, and End Results () database for cases of malignant melanoma that were diagnosed in individuals aged younger than 20 years between 2002 and 2015. After excluding all cases of adult melanoma and all cases of in situ melanoma, they included 1,620 patients in the final analysis and divided them into five age groups: less than 1 year, 1-4 years, 5-9 years, 10-14 years, and 15-19 years. They calculated the overall incidence rate per 100,000 population of pediatric melanoma based on data from the 2000 U.S. Census. Age-, sex-, and race-specific incidence rates were also calculated. Kaplan-Meier and Cox regression analyses to investigate disease-specific survival and risk factors.
With each successive age group, the investigators observed that incidence rate was significantly higher than that of the previous age group (P less than .005). “However, the most striking increase in incidence occurs between the age group of 10-14 and 15-19,” she said. “Sex also influenced incidence rates. Males had an incidence rate of 0.396 per 100,000 population while females had an incidence rate of 0.579 per 100,000 population.”
Race also influenced incidence rates. White patients had the highest incidence rate of 0.605 per 100,000 population, while blacks had the lowest incident rate at 0.042 per 100,000 population. American Indian and Alaska Native patients had incidence rates of 0.046 per 100,000 population, while Asians and Pacific Islanders had an incidence rate of 0.127 per 100,000 population.
The researchers found that increased survival was associated with white race, female sex, treatment with surgical intervention, and age older than 5 years. No differences in survival were observed regarding the primary anatomic location or extent of disease. The hazard ratio of death from invasive melanoma was significantly increased in males (HR, 2.34), black patients (HR, 3.96), other nonwhite patients (HR, 3.64), and in cases where surgery was not performed (HR, 6.04).
“It is surprising that, although incidence is significantly higher in white patients and females, compared to black patients and males, respectively, the risk of dying from melanoma is much higher in black patients and males,” Ms. Maddukuri said in an interview at the meeting. “Overall, the dermatologic community is on the right track in screening and diagnosing pediatric melanoma, as seen by the decreased incidence over the last 2 decades. However, increased awareness regarding pediatric melanoma is still encouraged. I believe we were able to identify certain populations that need more attention in terms of screening, diagnosis, and treatment, which are patients less than 5 years old, black and other nonwhite patients, and males.”
She acknowledged certain shortcomings of the study, including a limited clinical history of the patient population because of the nature of the database. She also said that further studies are required to investigate the contributing factors to decreasing incidence and to evaluate the relationship of the favorable prognostic factors to increased survival. The researchers are currently working on correlating incidence rates with UV exposure and geographical location.
They reported having no financial disclosures.