This suggests the possible utility of methylation analysis in CTCs for clinical purposes.510 The potential of circulating tumor DNA to identify EGFR mutations in lung cancer patients was examined by Hulbert et al.511 In identifying individuals who may benefit from treatment with tyrosine kinase inhibitors, the study demonstrated the utility of circulating tumor DNA as a feasible alternative to invasive tissue biopsies. Here, EGFR is linked to neoplasm.