EGFR and KRAS mutational analysis in a large series of Italian non-small cell lung cancer patients: 2,387 cases from a single center

Activating EGFR mutations are important genetic alterations that have strong therapeutic implications for non-small cell lung cancer (NSCLC) patients. However, the role of KRAS mutations in this process is still under evaluation. Here, we report on the feasibility of a large-scale EGFR and KRAS mutation analysis in the daily routine of a single center. NSCLCs from 2,387 patients were screened for EGFR and KRAS mutations from January 2010 to September 2015. Mutational analyses were performed in a single laboratory using single strand conformation polymorphism (SSCP)-Sanger sequencing and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) on Sequenom platform for EGFR and pyrosequencing for KRAS. Activating EGFR mutations were found in 14.1% of all tumors, whereas KRAS mutations were found in 30.5% of all tumors. Direct sequencing showed analyzable cytological, small biopsy and surgical specimen percentages of 90.3, 90.9 and 98.1%, respectively, whereas the MALDI-TOF platform showed analyzable cytological samples, small biopsies and surgical specimens percentages of 94.6, 95.7 and 96.9%, respectively. The mean analytical turnaround times (TAT) were 4 and 3 days for direct sequencing and the MALDI-TOF platform, respectively. Our results confirm that small biopsy or cytological samples can be used for reliable EGFR and KRAS mutation testing and indicate that adopting the MALDI-TOF platform reduces the rate of missed samples among the samples. Moreover, the 3-day analytical TAT of the MALDI-TOF multi-target technique is appropriate for clinical management and reduces the overall treatment decision time.