Fig. 4

Overview of mutant allele frequencies in tumour DNA (tDNA) and cfDNA per patient. All ctDNA allele frequencies are shown, including those with altered read number and allele frequencies below our threshold. Two different mutations were detected in CDKN2A in ESCC09 and in EPHA4 in ESCC10. For all mutations, a much lower MAF was observed in post-surgery cfDNA. The black boxes indicate the tumour-specific somatic mutations that were detected in either pre- or post-surgery cfDNA plasma samples