While the detection of T790M resistance mutation in plasma has led to the spread of liquid biopsy in clinical practice, the phase III FLAURA trial assessed the superiority of osimertinib over gefitinib or erlotinib in first-line setting [76, 77] and established osimertinib as standard treatment for first-line therapy in EGFR-mutated advanced NSCLC, thus opening new perspectives for liquid biopsy applications. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.