EGFR and neoplasm: NSCLC patients with EGFR-activating mutations in their tumours had significantly higher plasma levels of miR-504 compared to those with wild-type EGFR, regardless of the normalisation approach used (p = 0.0072 for miR-191-normalised data; p = 0.0236 for miR-16-normalised data; Fig. 3).