NF1 and melanoma: With regard to anatomic location, NF1 mutant tumors (n = 22/47, 46.8%), TWT melanomas (n = 14/33, 42.4%) and co-mutant tumors (n = 7/20, 35%) occurred more frequently on the head/neck compared with BRAF or NRAS mutant tumors (n = 24/154, 15.6%; p < 0.001, chi-squared test) (Figure S1a).