Higher rates of regional disease but improved outcomes in pediatric versus adult melanoma.

Background: Malignant melanoma is rare in the pediatric population and management is largely extrapolated from adult guidelines. Adult data have shown that immediate completion lymph node dissection (CLND) does not improve overall survival in selected patients with clinically node negative, sentinel lymph node-positive disease. Current nodal management in children is unknown.

Methods: The National Cancer Database (NCDB) was queried for patients with melanoma from 2012-2017 and patients categorized as pediatric (≤18 years, n=962) or adult (n=327,987). Factors associated with CLND in children with positive SLNB were evaluated in multivariable analysis. Kaplan-Meier survival analysis was performed.

Results: Compared to adults, children present with thicker primary tumors (T3 or T4 26.5% vs 15.5%, p<0.001), resulting in higher rates of nodal assessment with SLN biopsy or LND (60.2% vs 36.6%, p<0.001) and higher rates of regional nodal disease (35.1% vs 23.4%, p<0.001). Children underwent higher rates of CLND after SLN biopsy (10.4% vs 4.1%) and upfront lymph node dissection (15.2% vs 8.7%). A decreased rate of CLND was noted in 2017 compared to 2012 (odds ratio (OR) 0.16 (p=0.005). CLND was performed more often on multivariable analysis for older pediatric age (>12 years, OR=1.6, p=0.037) and lower extremity primary (OR=0.29, p<0.001). Children with regional nodal disease have improved 3-year overall survival compared to adults (96.5% vs 71.0%, p<0.001).

Conclusions: Children with melanoma have higher rates of nodal disease but better survival than adults. As in adults, there has been a recent increase in close nodal observation rather than CLND for patients with positive SLN. Further study of nodal surveillance for pediatric patients is warranted.