The median plasma cfDNA concentration of tumor-tissue EGFR M+ patients was lower than that of EGFR M- patients (9.61 ng/mL vs. 12.82 ng/mL, P = 0.049), possibly indicating that less cfDNA is released from the tumors of the EGFR M+ patients than from those of the EGFR M- patients. Here, EGFR is linked to neoplasm.