A comparison of methods for EGFR mutation testing in non-small cell lung cancer.

Abstract

EGFR mutation testing of tumor samples is routinely performed to predict sensitivity to treatment with tyrosine kinase inhibitors for patients with non-small cell lung cancer. At least 9 different methodologies are employed in UK laboratories, and the aim of this study was to compare the sensitivity of different methods for the detection of EGFR mutations. Participating laboratories were sent coded samples with varying mutation loads (from 0% to 15%) to be tested for the p.Leu858Arg (p.L858R) missense mutation and c.2235_2249del exon 19 deletion. The p.L858R mutation and deletions within exon 19 of the EGFR gene account for ∼90% of mutation-positive cases. The 11 laboratories used their standard testing method(s) and submitted 15 sets of results for the p.L858R samples and 10 for the exon 19 deletion. The p.Leu858Arg (p.L858R) mutation was detected at levels between 1% and 7.5% by Sanger sequencing, pyrosequencing, real-time polymerase chain reaction (PCR), amplification refractory mutation system, and capillary electrophoresis single-strand conformation analysis. The c.2235_2249del mutation was detected at 1% to 5% by fragment size analysis, Sanger sequencing or real-time PCR. A mutation was detected in 24/25 (96%) of the samples tested which contained 5% mutated DNA. The 1% sensitivity claimed for commercial real-time PCR-targeted EGFR tests was achieved and our results show greater sensitivity for the Sanger sequencing and pyrosequencing screening methods compared to the 10% to 20% detection levels cited on clinical diagnostic reports. We conclude that multiple methodologies are suitable for the detection of acquired EGFR mutations.

• Authors: Elizabeth C Young, Martina M Owens, Idowu Adebiyi, Tina Bedenham, Rachel Butler, Jonathan Callaway, Treena Cranston, Charlene Crosby, Ian A Cree, Laura Dutton, Catherine Faulkes, Claire Faulkner, Emma Howard, Julia Knight, Yuanxue Huang, Louise Lavender, Lazarus P Lazarou, Hongxiang Liu, Debbie Mair, Antonio Milano, Stacey Sandell, Alison Skinner, Andrew Wallace, Maggie Williams, Vicky Spivey, John Goodall, Jonathan Frampton, Sian Ellard, Clinical Molecular Genetics Society (CMGS) Scientific Subcommittee
• Journal: Diagnostic molecular pathology : the American journal of surgical pathology, part B (Diagn Mol Pathol) Vol. 22 Issue 4 Pg. 190-5 (Dec 2013) ISSN: 1533-4066 [Electronic] United States
• PMID: 24193010 (Publication Type: Comparative Study, Evaluation Study, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't)

Chemical References

• EGFR protein, human
• ErbB Receptors

Topics

• Carcinoma, Non-Small-Cell Lung (drug therapy, pathology)
• ErbB Receptors (genetics)
• Humans
• Mutation, Missense
• Pathology, Molecular (methods)
• Sensitivity and Specificity
• Sequence Deletion
• United Kingdom