Treatment of advanced lung cancer based on genomic profiling using liquid biopsy (plasma): A review of three cases

Of the 80 solid tumor cases in which liquid biopsy (LB) was performed using Guardant360 in the PROFILE study, nine were lung cancer cases. Here, we review three cases in which LB was useful in diagnosing ALK fusion‐positive lung cancer, selecting sequential ALK‐tyrosine kinase inhibitors, confirming uncommon EGFR mutations, and receiving biomarker‐compatible therapy. For advanced lung cancer, the genome profiling test by minimally invasive liquid biopsy (LB) is gathering attention. Herein, we showed three cases who received target therapy based on LB. LB assisted in diagnosing EML‐ALK fusion‐positive lung cancer in case 1, detected resistance genes for ALK inhibitor, ALK E1210K and F1174C in case 2, and detected uncommon EGFR mutations that could not be detected by a conventional test in case 3. In these cases, target therapy based on genome profiling resulted in a favorable therapeutic effect.