Fig. 5

Plasma longitudinal follow-up of the TERTp C228T mutation in a patient (#082) with TERTp-mutated gliosarcoma. a Patient #082 was a 69-year-old woman suffering from left temporal unmethylated MGMTp, IDH wild-type (wt) gliosarcoma with C228T TERTp mutation (MAF 28.6% in initial resected tumor using ddPCR). Partial tumor resection was initially performed. The plot shows the evolution of MAF and plasma cfDNA concentration as a function of time. C228T TERTp mutation was not detected in plasma until cerebral relapse, with sphenoid bone invasion. The longitudinal plasma samples taken during the first-line treatment schedule revealed a correlation between circulating C228T TERTp MAF, cfDNA concentration, and the evolution towards metastatic status. b Two representations of the search for TERTp C228T mutation in plasma at baseline (left) and at progression (right). Channel 1 fluorescence (vertical axis, FAM™) is plotted against channel 2 (horizontal axis, HEX™). Droplets are grouped as clusters: FAM™/HEX™negative (double-negative droplets, blue points), FAM™positive/HEX™negative (green points), FAM™negative/HEX™positive (pink points), and FAM™/HEX™positive (double-positive droplets, orange points)