Fig. 2

Differential cfDNA methylation between cancer and non-cancer samples enables accurate cancer detection. A-B The average methylation level of all target CpG sites in cancer patients (Cancer) and controls (Non-Cancer) from cohort 1 (A) and cohort 2 (B). C-D Scatter plots showing PC1 and PC2 from PCA of methylation level of all target CpG sites in cancer patients (Cancer) and controls (Non-Cancer) of cohort 1 (C) and cohort 2 (D). The percentage of variances explained by each PC is shown in the parentheses. E-F Receiver operating characteristic (ROC) curves of model performance based on the methylation level of CpG sites for cohort 1 (E) and cohort 2 (F). The results from 130 iterations for cohort 1 and 332 iterations for cohort 2 of leave-one-out cross-validation analysis were shown