RT Journal Article SR Electronic T1 RNA is Favorable for Analyzing EGFR Mutations in Malignant Pleural Effusion of Lung Cancer JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP erj00435-2011 DO 10.1183/09031936.00043511 A1 T-H. Tsai A1 K-Y. Su A1 S-G. Wu A1 Y-L. Chang A1 S-C. Luo A1 I-S. Jan A1 C-J. Yu A1 S-L. Yu A1 J-Y. Shih A1 P-C. Yang YR 2011 UL http://erj.ersjournals.com/content/early/2011/06/28/09031936.00043511.abstract AB Malignant pleural effusion (MPE) is a useful specimen allowing for the evaluation of EGFR status in non-small-cell lung cancer (NSCLC). However, direct sequencing of genomic DNA from MPE samples was found not sensitive for EGFR-mutation detection.To test whether EGFR analysis from RNA is less prone to interference from nontumor cells which have no or lower EGFR expression, we compared three methods (sequencing from cell-derived RNA versus sequencing and mass-spectrometric analysis from genomic DNA) parallelly for EGFR-mutation detection from MPE samples in 150 lung adenocarcinoma patients receiving first-line TKIs.Among these MPE samples, EGFR mutations were much more frequently identified by sequencing using RNA than by sequencing and mass-spectrometric analysis from genomic DNA (for all mutations, 67.3% versus 44.7% and 46.7%; for L858R or exon 19 deletions, 61.3% versus 41.3% and 46.7%). The better mutation-detection yield of sequencing from RNA was coupled with the superior prediction of clinical efficacy to first-line TKIs. In patients with acquired resistance, EGFR sequencing from RNA provided satisfactory detection of T790M (54.2%).These results demonstrated that EGFR sequencing using RNA as template greatly improves sensitivity for EGFR-mutation detection from samples of MPE, highlighting RNA as the favorable source for analyzing EGFR mutations from heterogeneous MPE specimens in NSCLC.