Survival and Surgical Outcomes for Pediatric Head and Neck Melanoma.

Importance: Melanoma in children is rare, accounting for approximately 2% of all pediatric malignant neoplasms. However, for the past 30 years, the incidence of melanoma in those younger than 20 years has been increasing. Location of the primary tumor has been shown to be an important prognostic factor, with melanomas of the scalp and neck conferring a worse prognosis than those originating at other sites.

Objective: To examine the survival, demographic, tumor, and treatment characteristics of pediatric head and neck melanoma.

Design, Setting, and Participants: We performed a retrospective cohort study using information from the National Cancer Data Base from January 1, 1998, to December 31, 2012, on pediatric (≤18 years) and adult (>18 years) patients with head and neck melanoma. Data analysis was conducted from August 1, 2015, to June 30, 2016.

Exposure: Pediatric age (≤18 years) at diagnosis of head and neck melanoma.

Main Outcomes and Measures: Survival differences were estimated using a Cox proportional hazards regression model. Surgical outcomes, including nodal sampling and margin status, were estimated with generalized linear models comparing pediatric and adult patients. Patient demographic, tumor, and treatment characteristics were estimated using t tests and χ2 tests between pediatric and adult patients with head and neck melanoma for continuous and categorical data, respectively.

Results: Of the 84 744 patients with head and neck melanoma, 657 (0.8%) were 18 years or younger (mean [SD] age, 13.5 [4.7] years; 285 female and 372 male; 610 white). Pediatric and adult patients had similar demographics but different histologic subtypes (risk difference of pediatric vs adult patients: melanoma, not otherwise specified, 8.5% [95% CI, 4.7%-12.3%]; superficial spreading, 4.2% [95% CI, 0.89%-7.4%]; and lentigo maligna, -13.4% [95% CI, -14.1% to 12.6%]). Pediatric patients had tumors of similar mean depth to those in adult patients (pediatric, 1.54 mm; adult; 1.39 mm; absolute difference, 0.15 mm; [95% CI, -0.32 to 0.008]) and more frequent nodal metastases than did adult patients (risk difference of pediatric vs adult patients for stage T2, 23.9% [95% CI, 14.1%-33.6%]). Five-year survival among pediatric patients was higher for those with stage 1, 2, or 3 disease (absolute difference of pediatric vs adult patients: stage 1, 18% [95% CI, 9.7%-26.3%]; stage 2, 36% [95% CI, 25.3%-46.7%]; stage 3, 39% [95% CI, 26.8%-51.2%]; and stage 4, 2% [95% CI, -8.2% to 12.2%]).

Conclusions and Relevance: Although pediatric patients with head and neck melanoma present with similar tumor depth and more frequent nodal metastases than do adult patients, younger patients have higher overall survival.