Screening Of Nsclc Samples From Chinese Lung Cancer Patients For Activating Rearrangements Of The Alk, Ret, And Ros1 Genes.

e22066 Background: The ALK, RET, and ROS1 genes are involved in gene rearrangements in a fraction of non-small cell lung cancers. The resulting oncogenic fusion genes define molecular sub-types of NSCLC with distinct sensitivities to treatment with various kinase inhibitors. We developed real-time reverse transcriptase PCR assays to detect rearrangements of ALK, RET, and ROS1 in FFPE lung cancer tissue. Methods: mRNA from NSCLC FFPE tissue samples was reverse transcribed to cDNA. Multiplex quantitative PCR was performed to detect 9 variants of EML4-ALK fusions, 9 variants of RET fusions and 14 variants of ROS1 fusions. A total of 409 samples were analyzed: 267 were classified as adenocarcinoma, 104 as squamous cell carcinoma and 38 had undetermined histology. EGFR and KRAS mutation status is unknown. The junctions of fusion-positive samples were sequenced by Sanger sequencing. Results: Among the 409 NSCLC specimens tested the frequency was 5.4% (22/409) for EML4-ALK fusions, 1.5% (6/409) for RET fusions, ...