T790M detection rate after first-line combination therapy with bevacizumab and EGFR-TKIs in advanced NSCLC (TERRA Study).

Real-world data regarding the T790M mutation rate after acquiring resistance to first-line combination therapy with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and bevacizumab in patients with advanced non-small-cell lung cancer (NSCLC) are limited. The present study was aimed at analyzing predictors of acquired T790M mutations in this patient group. A total of 107 patients who received first-line combination therapy with EGFR-TKIs and bevacizumab at 11 tertiary referral centers in Taiwan were enrolled in this multicenter retrospective study. Survival data and genomic test results after acquiring resistance were analyzed. We discovered that patients who received a combination of afatinib, a second generation EGFR-TKI, and bevacizumab showed better progression-free survival (PFS). After disease progression, 59 patients (55.1%) were confirmed to test positive for EGFR T790M. A longer duration of first-line therapy could be a predictor of subsequent T790M mutations. To our knowledge, this is one of the few and early studies to demonstrate the T790M mutation rate after first-line combination therapy with an EGFR-TKI and bevacizumab. Whether the longer PFS afforded by the addition of bevacizumab could lead to subsequent T790M mutations needs further investigation.