Data from Effective Assessment of <i>egfr</i> Mutation Status in Bronchoalveolar Lavage and Pleural Fluids by Next-Generation Sequencing

Abstract

<div>Abstract<p><b>Purpose:</b> The therapeutic choice for patients with lung adenocarcinoma depends on the presence of EGF receptor (<i>EGFR</i>) mutations. In many cases, only cytologic samples are available for molecular diagnosis. Bronchoalveolar lavage (BAL) and pleural fluid, which represent a considerable proportion of cytologic specimens, cannot always be used for molecular testing because of low rate of tumor cells.</p><p><b>Experimental Design:</b> We tested the feasibility of <i>EGFR</i> mutation analysis on BAL and pleural fluid samples by next-generation sequencing (NGS), an innovative and extremely sensitive platform. The study was devised to extend the <i>EGFR</i> test to those patients who could not get it due to the paucity of biologic material. A series of 830 lung cytology specimens was used to select 48 samples (BAL and pleural fluid) from patients with <i>EGFR</i> mutations in resected tumors. These samples included 36 cases with 0.3% to 9% of neoplastic cells (series A) and 12 cases without evidence of tumor (series B). All samples were analyzed by Sanger sequencing and NGS on 454 Roche platform. A mean of 21,130 ± 2,370 sequences per sample were obtained by NGS.</p><p><b>Results:</b> In series A, <i>EGFR</i> mutations were detected in 16% of cases by Sanger sequencing and in 81% of cases by NGS. Seventy-seven percent of cases found to be negative by Sanger sequencing showed mutations by NGS. In series B, all samples were negative for <i>EGFR</i> mutation by Sanger sequencing whereas 42% of them were positive by NGS.</p><p><b>Conclusions:</b> The very sensitive <i>EGFR</i>-NGS assay may open up to the possibility of specific treatments for patients otherwise doomed to re-biopsies or nontargeted therapies. <i>Clin Cancer Res; 19(3); 691–8. ©2012 AACR</i>.</p></div>