Table 2.

Concordance analysis of EGFR mutation detection by targeted tissue EGFR testing and plasma NGS for 37 NSCLC cases.

		Tissue EGFR testing (Sanger or targeted PCR)
		Positive	Negative	Total
Plasma NGS	Positive	9	0†	9	Sensitivity: 75% (95% CI: 42.8–94.5%) Specificity: 100% (95% CI: 86.3% to 100.0%) Accuracy: 91.9% (95% CI: 78.1% to 98.3%)
	Negative	3	25	28

Sensitivity of plasma NGS for EGFR detection relative to tissue EGFR testing was 75% (9/12) and specificity was 100% (25/25), for an overall concordance of 91.9% (34/37).

^†One case in plasma NGS was found to have EGFR p.A763_Y764insFQQA, an exon 20 insertion mutation, which is not part of the assay used in routine PCR-based tissue EGFR testing, and is not included in the count.