Clinical application of targeted next generation sequencing for lung cancer patients

Summary

The successes of targeted agents in patients with molecularly defined tumours and improvements in genomic technology have generated enthusiasm for incorporating genomic profiling into clinical cancer practice and molecular testing has now become a standard of care for lung cancer. International guidelines recommend testing for EGFR mutations and ALK gene rearrangement to guide patient selection for therapy. However, different potentially targetable oncogenes, such as KRAS, PIK3CA, BRAF, ERBB2 or MET, for which agents are being evaluated, have been proposed as valuable for managing patients with lung cancer. Recently, the development of next generation sequencing has enabled simultaneous detection of many clinically relevant mutations in different genes in a single test. In this study, we have evaluated the clinical utility of targeted next generation sequencing, using a 22 genes panel, for patients with lung cancer on 234 samples, including cytology, biopsies and surgical resections, from two different institutions tested in routine daily practice since validation and accreditation of the method (BELAC ISO15189). On the 234 samples tested, only one case could not be sequenced due to an insufficient quantity of available tissue. Among the 233 cases tested, 223 (95.7%) samples were sequenced successfully. The median turnaround time between reception of the sample in the laboratory and report release was one week. The most frequent mutations were found in TP53 (42.1%) and KRAS (35.9%). Of successfully sequenced cases, 137 potentially actionable mutations were identified in 130 patients (58.3%), including 80 KRAS mutations, 26 EGFR mutations, fourteen BRAF mutations, eight PIK3CA mutations, three PTEN mutations, two ERBB2 insertions, two NRAS mutations and two MAP2K1 mutations. Overall, next generation sequencing can be applied in daily practice even for small samples, such as lung biopsies or cell blocks. Moreover, it provides clinically relevant information for lung cancer patients.

(BELG J MED ONCOL 2015;9(7):272–78)