NF1 and neoplasm: The prognostic association was stronger for DNA copy number gains than losses, and the burden of gains had independent prognostic value in a multivariable analysis including NF1-status, age, sex, and remission status of the patients, as well as tumour location and size (burden of gain analysed as a continuous variable: HR = 1.04, 95% CI 1.01–1.08, P = 0.004 from Wald test; Supplementary Table S8).