Fig. 1.

Example of qPCR mutation analysis in the EGFR gene in DNA isolated from an FFPE tissue sample (I) and ctDNA in patient 1 (II.A, II.B, II.C). Deletion in EGFR exon 19 (I; July 2015) detected in FFPE cancer tissue. No EGFR mutation detected in plasma ctDNA in November 2015 (dotted arrow) – II.A, May 2016 – II.B, December 2016 – II.C. Stabilization of disease progression. Lack of detection of exon 19 deletion in ctEGFR from November 2015 to December 2016 correlates with stabilization of disease confirmed clinically using a broad range of medical imaging techniques