Lack association between BIM deletion polymorphism and efficacy of EGFR-TKIs in NSCLC based on NGS

Abstract

Abstract Background BIM deletion polymorphisms are most common in the Asian population, with an incidence of 12-16% in lung cancer patients with EGFR mutations. Owing to loss function in mediating apoptosis of tumor cells, BIM deletion polymorphisms could be on of the reasons of primary resistance of EGFR-TKIs. However, availble evidence on BIM is inconsistent and we don’t know if NGS could bring us something new. Methods Data were pooled from prospective clinical trial CTONG0901 and local database of our hospital. 194 and 117 EGFR mutant patients with IIIB/IV NSCLC are enrolled for analysis in the two cohorts, respectively. BIM status were detected by NGS. Results The incidence of BIM deletion polymorphism was 11.5% (22/194) in CTONG0901 and 17.6% (26/148) in our database. No matter for all patients, TKIs in first line, TKIs in second line, patients with 19 deletion or patients with 21L858R mutation, there are no statistical differences between patients with or without BIM deletion polymorphism on PFS or OS. In the two cohorts, baseline NGS results were analyzed in 27 patients with BIM deletion polymorphism. 1 patient with MET amplification, 1with ALK rearrangement and 1with positive PD-L1 expression (20% +++), among 11 patients who were under median PFS (8.63 months). Conclusions Although NGS also tell us that BIM has no influence on EGFR-TKIs, other genes detection seems more important to the prediction of EGFR-TKIs on NSCLC, such as T790M mutation, MET amplification, ALK rearrangement and others.