Germline genomic findings in children and young adults with melanocytic tumors.

In this retrospective study, we examined the prevalence and spectrum of germline variants in selected cancer predisposition genes in 38 children and young adults with melanocytic lesions at St. Jude Children's Research Hospital. Diagnoses included malignant melanoma (n = 16; 42%), spitzoid melanoma (n = 16; 42%), uveal melanoma (n = 5; 13%), and malignant melanoma arising in a giant congenital melanocytic nevus (n = 1; 3%). Six patients (15.8%) harbored pathogenic germline variants: one with bi-allelic PMS2 variants, one with a heterozygous 17q21.31 deletion, and one each with a pathogenic variant in TP53, BRIP1, ATM, or AXIN2. Overall, 15.8% of patients harbored a cancer-predisposing genetic variant.