In NRAS mutant patients of the validation cohort, NOTCH4 wildtype melanoma had longer OS (mOS: 31.3 months vs. 22.6 months, HR = 1.23, 95% CI: 0.48–3.18, P = 0.68) than NOTCH4-Mut patients (Supplementary Figure S3). This evidence concerns the gene NOTCH4 and melanoma.