title: Ethnicity affectsEGFRandKRASgene alterations of lung adenocarcinoma.
abstract: Mutations or copy number gains (CNGs) of theEGFRandKRASgenes are representative alterations in lung adenocarcinomas that are individually associated with patient characteristics such as ethnicity, smoking status and gender. However, the effects of combinations of these genetic alterations have not been statistically examined. The present study analyzed previously examined lung adenocarcinoma cases in Asian (n=166) and non-Asian (n=136) individuals in whom all fourEGFRandKRASalterations had been studied. The polynomial logistic regression models were used following adjustment for gender and smoking status, and using patients without any type ofEGFR/KRASalterations as a reference. Between the two ethnic groups,EGFRCNGs (gEGFR) occurred more frequently thanEGFRmutations (mEGFR) (46 vs. 38% in Asians; 21 vs. 10% in non-Asians), whereasKRASmutations (mKRAS) were more frequent thanKRASCNGs (gKRAS) (13 vs. 7% and 35 vs. 4%, respectively). Additionally, gEGFRand gKRASoccurred significantly more frequently in respective mutant cases, and allEGFRalterations were almost exclusive of allKRASalterations. The polynomial logistic regression models confirmed that all types ofEGFRalterations were significantly more frequent among Asian individuals than among non-Asian individuals, independent of gender and smoking status (odds ratios, 2.36-6.67).KRASalterations occurred less frequently among Asian individuals than among non-Asian individuals, although a significant difference was not detected. The present study results indicated that theEGFRandKRASprofiles, including mutations and CNGs, differ between Asian and non-Asian individuals with lung adenocarcinoma, suggesting that ethnicity strongly affects the molecular characteristics of lung adenocarcinoma.
authors.affiliation: Department of Thoracic Surgery Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan ; Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Junichi
authors.initials: J
authors.lastname: Soh
authors.affiliation: Department of Thoracic Surgery Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan ; Department of Clinical Genomic Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Toyooka
authors.affiliation: Department of Preventive Medicine, Kyushu University Faculty of Medical Sciences, Fukuoka, Fukuoka, Japan.
authors.forename: Keitaro
authors.initials: K
authors.lastname: Matsuo
authors.affiliation: Department of Thoracic Surgery Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan.
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA ; Department of Thoracic/Head and Neck Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Ignacio I
authors.initials: II
authors.lastname: Wistuba
authors.affiliation: Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, BC, Canada.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lam
authors.affiliation: Department of Thoracic Medicine, The Prince Charles Hospital, Brisbane, Australia.
authors.forename: Kwun M
authors.initials: KM
authors.lastname: Fong
authors.affiliation: Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA ; Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Adi F
authors.initials: AF
authors.lastname: Gazdar
authors.affiliation: Department of Thoracic Surgery Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Miyoshi
keywords: EGFR; KRAS; copy number gain; ethnicity; lung adenocarcinoma; mutation