title: Frequency of and variables associated with the EGFR mutation and its subtypes.
abstract: Mutation in the epidermal growth factor receptor (EGFR) is frequently seen in non-small cell lung cancers (NSCLCs), especially in Asian females with adenocarcinoma. The frequency of mutation and the factors associated requires to be elucidated by analyzing a large number of consecutive clinical samples. We summarized the result of the EGFR mutation analysis for 1,176 patients performed at the time of diagnosis or relapse. The PNA-LNA PCR clamp, a highly sensitive detection method for the EGFR mutation, was employed. For fresh cases a portion of samples isolated to establish the diagnosis of lung cancer was used. For cases with a relapsed disease archival tissue were tested. The variables associated with the EGFR mutation after removing the confound factors were investigated by the logistic analysis using the samples collected in our university (n = 308) where detailed information on patients were available. The frequency of the EGFR mutation and its subtypes were investigated using all samples (n = 1,176). The EGFR mutation was significantly associated with adenocarcinoma (p = 0.006) and light-smoking (p < 0.0001), but not gender. The deletions in exon 19 were more frequently associated with male gender while exon 21 deletions were with female gender (p = 0.0011). The overall frequency of the EGFR mutation was 31%. Our result suggests that the female predominance in the EGFR mutation rate is a reflection of a higher frequency of adenocarcinoma in females. The gender difference in the mutation subtypes may provide a clue for the mechanism of the occurrence of the EGFR mutation.
authors.affiliation: Department of Respiratory Medicine, Saitama Medical University, Moroyama-machi, Saitama, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Tanaka
authors.forename: Masaru
authors.initials: M
authors.lastname: Matsuoka
authors.forename: Akihisa
authors.initials: A
authors.lastname: Sutani
authors.forename: Akihiko
authors.initials: A
authors.lastname: Gemma
authors.forename: Makoto
authors.initials: M
authors.lastname: Maemondo
authors.forename: Akira
authors.initials: A
authors.lastname: Inoue
authors.forename: Shoji
authors.initials: S
authors.lastname: Okinaga
authors.forename: Makoto
authors.initials: M
authors.lastname: Nagashima
authors.forename: Satoshi
authors.initials: S
authors.lastname: Oizumi
authors.forename: Kazutsugu
authors.initials: K
authors.lastname: Uematsu
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nagai
authors.forename: Gaku
authors.initials: G
authors.lastname: Moriyama
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Miyazawa
authors.forename: Kenji
authors.initials: K
authors.lastname: Ikebuchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Koichi
authors.initials: K
authors.lastname: Hagiwara
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000453:epidemiology / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics; D005091:Exons / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D018773:Genes, erbB-1; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008175:Lung Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics*; D017354:Point Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D017384:Sequence Deletion; D012737:Sex Factors; D012907:Smoking / Q000235:genetics
chemical_list: D004273:DNA, Neoplasm; D009363:Neoplasm Proteins