Given the very low NTRK fusion frequency in NSCLC, ranging from about 0.07–3.3% for NTRK1, 0.02–0.2% for NTRK2 and 0.08% for NTRK3, a specific large multi-institutional study would be needed to fully validate the Idylla platform for this biomarker in NSCLC [19]. The gene discussed is NTRK1; the disease is non-small cell lung carcinoma.