Fig. 3: ctDNA fraction per body liquid and its association with surrounding metastases.

A Violin plots describing the distribution of the ctDNA fraction per body liquids, 95 samples are considered. All timepoints of collection are considered together, all pre-mortem blood samples are reported in the peripheral blood category. Body liquids are ranked by increasing median ctDNA fraction. B–E Violin plots representing the ctDNA fraction in each fluid according to the presence of metastases in the surrounding organs. Four liquids are considered: pleural fluid (B, 14 samples), CSF (C, 15 samples), ascites (D, 12 samples), and urine (E, 10 samples) with regards to metastases in the pleura, the central nervous system (brain, meninges, and/or spinal cord), the peritoneum and the bladder, respectively. In case of multiple samples available for the same body liquid in a patient, the one having the highest ctDNA fraction is kept. Only samples obtained at autopsy are considered and a paired Wilcoxon test is performed in each case for which the two-sided p-value is reported in the plot. A–E In all boxplots the box delineates Q1, median and Q3, while the whisker ranges from Q1-1.5*IQR to Q3+1.5*IQR. Samples are biological replicates. Data are derived from the lpWGS. Source data are provided as a Source Data file. ASC ascites, CSF cerebrospinal fluid, CNS central nervous system, CT connective tissue, ctDNA circulating tumor DNA, IQR inter quartile range, lpWGS low-pass whole genome sequencing,Met metastatic, PeriC pericardial fluid, periph peripheral, PFL pleural fluid, Q1 first quartile, Q3 third quartile, URN urine.