Moreover, in advanced NSCLC, the assessment of 73 hotspot mutations in EGFR, KRAS, BRAF, ERBB2, and PIK3CA demonstrated that a decrease in ctDNA levels 4–6 weeks after treatment initiation was associated with prolonged median progression-free survival (PFS) and OS [22]. This evidence concerns the gene PIK3CA and non-small cell lung carcinoma.