Melanoma patients diagnosed prior to age 18 had a higher survival vs adult patients, despite having similar tumor depth and more frequent nodal metastases.
Patients with melanoma diagnosed prior to the age of 18 had a higher survival compared with adult patients, despite having similar tumor depth and more frequent nodal metastases, according to the results of a study published in JAMA Otolaryngology-Head & Neck Surgery.
Pediatric patients had higher 5- and 10-year unadjusted survival rates for every stage of disease except stage IV.
“Despite a prevalent supposition that children do not die of melanoma, our research found this belief to be false,” wrote Morgan K. Richards, MD, MPH, of the University of Washington and Seattle Children’s Hospital, and colleagues. “Whether this finding is associated with melanoma itself or complications of treatment is yet to be determined. Further studies will be needed to better elucidate the pathophysiological differences responsible for better survival outcomes in pediatric patients with head and neck melanoma.”
Although melanoma only accounts for a small percentage of pediatric malignancies, the incidence of melanoma in people aged younger than 20 has increased in recent years. Additionally, melanomas of the scalp and neck are known to confer worse prognosis than other sites.
With this analysis, Richards and colleagues examined survival, and tumor and treatment characteristics of pediatric patients vs adult patients with melanoma of the head and neck. The researchers used data from the National Cancer Data Base from January 1998 to December 2012, and identified 84,744 patients (0.8% were 18 or younger).
“Previous studies have suggested that pediatric melanoma has a higher proportion of clinically atypical features, specifically amelanotic, pedunculated, and raised nodular lesions,” the researchers wrote. “We observed a higher proportion of melanoma, not otherwise specified, and ‘other’ histologic subtypes in pediatric patients, which may indicate a less straightforward diagnosis.”
Pediatric patients more frequently presented with malignant melanoma, superficial spreading, or stage III disease. Despite the fact that pediatric patients presented with similar tumor depth to that seen in the adult patients (1.54 mm in pediatric vs 1.39 mm in adults), pediatric patients more frequently had nodal metastases.
“There are several hypotheses to explain these findings. Melanoma is less common in pediatric patients, lowering the index of suspicion among primary care physicians,” the researchers noted. “Furthermore, performing a skin biopsy on a young child may require sedation or general anesthesia, which could raise a clinician’s threshold to perform a biopsy, resulting in delay.”
Nodal sampling was performed more often in pediatric patients, regardless of the stage of their disease (relative risk [RR], 1.35 [95% CI, 1.28–1.42]). Younger patients were about twice as likely to have positive nodes at resection compared with adults patients (RR, 1.98 [95% CI, 1.72–2.27]). In addition, surgical management was less likely to produce positive margins in pediatric patients compared with adult patients for stage T1 disease. No significant differences in margin status were seen for any other T stage.
Pediatric patients had significantly higher survival for stage I (absolute difference of pediatric vs adult patients, 18%), stage II (36%), and stage III disease (39%), but not for stage IV disease.