In 2008, Maheswaran et al. isolated CTCs from 27 patients with metastatic NSCLC, identifying the EGFR T790M mutation in 11/12 and 4/12 EGFR positive patients in CTCs and in matched plasma circulating cell-free DNA (cfDNA), respectively (p = 0.009). Here, EGFR is linked to non-small cell lung carcinoma.