title: Reliability of the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp-based test for epidermal growth factor receptor mutations integrated into the clinical practice for non-small cell lung cancers.
abstract: Gefitinib is an inhibitor of the tyrosine kinase activity of epidermal growth factor receptor (EGFR). Accumulating evidence suggests that gefitinib may provide a survival benefit to EGFR mutation-positive non-small lung cancer patients. We have established a clinical test that can detect EGFR mutations from cytological specimens or paraffin-embedded tissue specimens that are contaminated by normal cells. This test is based on the peptide nucleic acid, locked nucleic acid polymerase chain reaction clamp method that can detect G719S, G719C, L858R, L861Q and seven different exon 19 deletions in the presence of 100-1000-fold wild-type alleles. Consequently, using a small aliquot of samples isolated to establish a cancer diagnosis, the EGFR mutation status is determined soon after the diagnosis of cancer is made. We investigated the EGFR mutation status in 86 patients using a variety of cytological specimens (59 bronchoscopy specimens, 16 pleural effusion, 9 sputum, and 2 pericardial effusion) and in 46 patients who had a disease relapse and paraffin-embedded tissues were available. Forty-five patients (34%) were positive for mutation (29 exon 19 deletions, 16 L858R and 1 L861Q). The sensitivity and the specificity of this test was 97% and 100%, respectively. EGFR mutation status thereby obtained was used to determine each patient's therapeutic regimen. This test is easily integrated into the normal clinical practice for lung cancer, while allowing the medical staff to select therapeutic regimen depending on the EGFR mutation status.
authors.affiliation: Department of Respiratory Medicine, Saitama Medical University, Saitama 350-0495, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Tanaka
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nagai
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Miyazawa
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Koyama
authors.forename: Suguru
authors.initials: S
authors.lastname: Matsuoka
authors.forename: Akihisa
authors.initials: A
authors.lastname: Sutani
authors.lastname: Huqun
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Udagawa
authors.forename: Yoshitake
authors.initials: Y
authors.lastname: Murayama
authors.forename: Makoto
authors.initials: M
authors.lastname: Nagata
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Kenji
authors.initials: K
authors.lastname: Ikebuchi
authors.forename: Minoru
authors.initials: M
authors.lastname: Kanazawa
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Koichi
authors.initials: K
authors.lastname: Hagiwara
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000235:genetics*; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000737:chemistry / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D020135:Peptide Nucleic Acids / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D020135:Peptide Nucleic Acids; D066246:ErbB Receptors