ALK and non-small cell lung carcinoma: In 51 patients with ALK oncogene driven NSCLC receiving various selective EML4-ALK inhibitors, patients with ctDNA clearance using NGS at two months on therapy had better PFS 25.4 vs 11.6 mo, p = 0.0012 and OS (NR vs 26.1 mo, p = 0.0307) compared to those without ctDNA clearance [38].