Usefulness of EGFR mutation screening in pleural fluid to predict the clinical outcome of gefitinib treated patients with lung cancer

Abstract

The importance of epidermal growth factor receptor (EGFR) gene mutation has been recognized in nonsmall cell lung cancer (NSCLC), requiring the standardization of mutation screening system including the kind of samples. Here, we examined the EGFR mutation status in 61 pleural fluid samples from NSCLC cases using direct sequencing, nonenriched PCR, mutant-enriched PCR and peptide nucleic acid-locked nucleic acid (PNA-LNA) PCR clamp assay. The mutant-enriched PCR assay detected 16 mutant cases. Among them, the nonenriched PCR assay failed to detect 3 mutant cases. Regarding the discrepancy between mutant-enriched PCR and PNA-LNA PCR clamp assays, 3 cases of exon19-deletions were detected only by mutant-enriched PCR assay and no difference at the L858R mutation. There was no difference in results between direct sequencing and nonenriched PCR assay. We also correlated the EGFR mutation with clinical outcome of gefitinib-treated 29 cases. EGFR mutations were present in 10 cases, revealing 7 partial response and 3 no change (NC). In EGFR wild-type cases, 10 revealed NC and 9 progressive disease. The responders were significantly more frequent among the EGFR mutant cases than among the wild-type (p < 0.0001). Overall survival (p 5 0.0092) and progression-free survival (p 5 0.018) were significantly longer among the EGFR mutant cases than among the wild-type. In summary, we evaluated the utility of EGFR mutation screening in pleural fluid using 4 assays that showed some discrepancies arising from the designs of the assays. As clinical importance, the EGFR mutation status in pleural fluid can be a biomarker for the favorable outcome of gefitinib-treated NSCLC cases. ' 2006 Wiley-Liss, Inc.

Clinical screening assay for EGFR exon 19 mutations using PNA-clamp smart amplification process version 2 in lung adenocarcinoma

“…Thus, the advantages of the PNA-clamp SmartAmp2 assay will improve the efficacy of EGFR-TKI and other treatments and improve the quality of life of patients by minimizing the waiting time until the initiation of the appropriate treatment. Recently, the presence of EGFR mutations in plasma, serum, and pleural effusion has become a focus of interest (31)(32)(33)(34). The PNA-clamp SmartAmp2 assay may also contribute to the development of mutant DNA detection methods in these specimens, which contain extremely small amounts of mutant cells.…”

Detection of K-Ras mutations in tumour samples of patients with non-small cell lung cancer using PNA-mediated PCR clamping

“…Such a technique has been applied to search for K-Ras mutations in various tumour samples (Sun et al, 2002;Chen et al, 2004;Taback et al, 2004;Däbritz et al, 2005;Luo et al, 2006;Miyake et al, 2007). This method was also used to detect EGFR mutations in NSCLC (Nagai et al, 2005;Soh et al, 2006;Sutani et al, 2006;Tanaka et al, 2007;Miyanaga et al, 2008).…”

EGFR mutations predict a favorable outcome for malignant pleural effusion of lung adenocarcinoma with Tarceva therapy

“…Soh et al (38) and Gow et al (39) reported an EGFR mutation rate of 24.5% (13 out of 53) in MPEs of lung adenocarcinoma. Kimura et al (40) found a 13% (3 out of 23) EGFR mutation rate by direct sequencing of EGFR mutations in MPEs of lung adenocarcinoma, of which 9.1% (1 out of 11) were females and 10% (1 out of 10) were never smokers.…”