Utilization of Molecular Testing and Survival Outcomes of Treatment with First- or Second-line Tyrosine Kinase Inhibitors in Advanced Non-small Cell Lung Cancer in a Dutch Population.

Background/Aim: Epidermal growth factor receptor (EGFR) mutation testing is standard-of-care for advanced non-small cell lung cancer (NSCLC). Outcomes of second-/third-line compared to first-line tyrosine kinase inhibitors (TKIs) have shown conflicting results. We investigated utilization of molecular diagnostics and the outcomes of treatment with first-/second-line TKIs in patients with advanced NSCLC. Materials and Methods: Retrospective analysis was carried out of 2,206 patients with stage IIIb/IV NSCLC treated between 2008 and 2014 in four hospitals in the Netherlands. Results: The rate of performing molecular diagnostics increased from 20.8% to 74.4% in the study period. The median overall survival of EGFR mutation-positive patients treated with TKIs was superior compared to EGFR mutation-negative patients treated with chemotherapy (720 vs. 274 days, p<0.0001). No difference in overall survival was found between EGFR mutation-positive patients treated only with TKIs compared to those treated with chemotherapy prior to TKIs, or upon progression under TKIs. Conclusion: The rate of EGFR testing has improved, increasing the number of patients eligible for targeted therapy. Chemotherapy, prior or subsequent to TKIs, for the treatment of EGFR mutation-positive patients, did not result in significantly better overall survival compared to that achieved with TKIs alone.