EGFR and neoplasm: To this end, circulating tumor DNA (ctDNA) sequencing in liquid biopsy (LB) is regarded as the preferred approach to fine-tune the identification of patients candidate for anti-EGFR retreatment, as reported by post-hoc translational analyses of single-arm phase II studies, showing no benefit in patients with RAS/BRAF mutant ctDNA, and the recent prospective ctDNA-guided CHRONOS trial, reporting an ORR of 30% in patients with RAS/BRAF wt ctDNA (1–3, 6).