Multicenter Evaluation of the Idylla GeneFusion in Non–Small-Cell Lung Cancer

Targeted therapy in lung cancer requires the assessment of multiple oncogenic driver alterations, including fusion genes. This retrospective study evaluated the Idylla GeneFusion prototype, an automated and ease-of-use (<2 minutes) test, with a short turnaround time (3 hours) to detect fusions involving ALK, ROS1, RET and NTRK1/2/3 genes and MET exon 14 skipping. This multicenter study (18 centers) included 313 FFPE tissue samples from lung cancer patients with 97 ALK, 44 ROS1, 20 RET, 5 NTRKs fusions, 32 MET exon 14 skipping and 115 wild-type samples, previously identified with reference methods (RNA-based NGS/FISH/qPCR). Valid results were obtained for 306 cases (98%), the overall concordance between Idylla and reference methods was 89% (273/306), the overall sensitivity and specificity were 85% (165/193) and 96% (108/113), respectively. Discordances were observed in 28 samples, where Idylla did not detect the alteration identified by the reference methods; and 5 samples where Idylla identified an alteration (by expression imbalance only) not detected by the reference methods. All of the ALK, ROS1 and RET specific fusions and MET exon 14 skipping identified by Idylla GeneFusion were confirmed by reference method. To conclude, Idylla GeneFusion is a clinically valuable test that does not require a specific infrastructure, allowing a rapid result. The absence of alteration or the detection of expression imbalance only requires additional testing by orthogonal methods.