Incidence of FGFR-TACC gene fusions in Chinese non-small cell lung cancer (NSCLC): A multicenter study.

Abstract

e13001 Background: Fibroblast growth factor receptors (FGFR) are transmembrane kinase proteins with growing importance in non-small cell lung cancer (NSCLC) biology given the frequency of molecular alterations and vast interface with multiple other signaling pathways. Furthermore, numerous FGFR inhibitors in clinical development demonstrate the expanding therapeutic relevance of this pathway. The aim of this study was to evaluate the prevalence of FGFR-TACC fusions in Chinese NSCLC populations, which had not been reported earlier, and to describe targeting potential in Chinese NSCLC populations. Methods: A multicenter study in China was initiated from February 2014, and NSCLC patients have been enrolled as of December 2018. Capture-based comprehensive genomic profiling was performed on 2743 NSCLC FFPE samples sequenced to a mean coverage depth of > 650X for up to 381 cancer-related genes. Genomic alterations (GA) included short variant (SV) base subs and insertions/deletions, copy number alterations, and rearrangements/fusions. Tumor mutational burden (TMB; mut/Mb) was calculated on up to 1.2 Mb of sequenced DNA. Results: Of this entire cohort, just 16 (0.58%) patients were identified with FGFR-TACC fusions, including FGFR1-TACC 1 fusion (1), FGFR2-TACC2 fusion (3) and FGFR3-TACC3 fusion (12). Median patient age was 57 (range 36-84 years). Of the FGFR-TACC fusion NSCLC patients, 56.25% were detected in female patients. Biopsies were obtained from primary lung tumor (31.25%) and metastatic sites (68.75%). Overall TMB in the FGFR-TACC fusion was low (median 3.6 mut/Mb), although two cases (12.50%) had > 20 mut/Mb. Of the FGFR-TACC fusion NSCLC patients, two cases (12.50%) featured EGFR SV alterations. Conclusions: FGFR-TACC fusions occur in a subset of patients with NSCLC. Such patients should be considered for clinical trials featuring FGFR inhibitors (AZD4547). Moreover, NGS can provide information for targeted therapy. For NSCLC patients to benefit from more personalized cancer treatment, clinical therapy should improve with clinical diagnostics through multi-gene assays to determine the actual clinical benefits.