Other studies have shown an association between early clearance of ctDNA analyzed between 2-8 weeks and PFS in patients with EGFR mutant NSCLC in trials of gefitinib, afatinib, osimertinib, and multiple other EGFR TKIs [14, 26, 33–37]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.