title: Prognostic value of K-RAS mutations in patients with non-small cell lung cancer: a systematic review with meta-analysis.
abstract: K-RAS gene mutations have been found in 20-30% of non-small cell lung cancer and occur most commonly in adenocarcinoma, however, there was no definitive conclusion about the prognostic role of K-RAS mutations in NSCLC. Herein we performed a systematic review of the literatures with meta-analysis to assess K-RAS mutations' prognostic value in NSCLC. After a methodological assessment, survival data from published studies were aggregated. Combined hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated in terms of overall survival. 41 trials (6939 patients) were included in the analysis, the overall HR was 1.45 (95% CI: 1.29-1.62), showing that K-RAS mutations have an unfavorable impact on survival of patients with NSCLC. Then a subgroup analysis was performed about ethnicity, the combined HR was 1.97 (95% CI: 1.58-2.44) for Asians, and 1.37 (95% CI: 1.25-1.5) for non-Asians. In subgroup analysis of histology, the HR was 1.39 (95% CI: 1.24-1.55) for adenocarcinoma, suggesting that K-RAS mutations were correlated with shortened survival for adenocarcinoma. When the subgroup analysis was conducted according to disease stage, K-RAS mutations were poor prognostic factors in early stages: stage I (1.81; 95% CI: 1.36-2.39) and stage I-IIIa (1.68; 95% CI: 1.11-2.55), but not in advanced stage (IIIb-IV) (1.3; 95% CI: 0.99-1.71). At last, in subgroup analysis about test methods, all of the four methods: PCR-MSOP (1.73; 95% CI: 1.35-2.2), PCR-DGGE (1.27; 95% CI: 1.01-1.62), PCR-RFLP (1.88; 95% CI: 1.42-2.49) and PCR-seq (1.34; 95% CI: 1.14-1.58) showed statistically significant impact on survival of NSCLC patients. In conclusion, this meta-analysis suggests that K-RAS mutations are associated with a worse overall survival in patients with NSCLC, especially in patients with adenocarcinoma and early stage.
authors.affiliation: Department of Respiratory and Critical Care Medicine, Key Laboratory of Pulmonary Diseases of Health Ministry, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 jiefang Avenue, Wuhan 430022, PR China.
authors.forename: Daquan
authors.initials: D
authors.lastname: Meng
authors.forename: Mingli
authors.initials: M
authors.lastname: Yuan
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Li
authors.forename: Lijun
authors.initials: L
authors.lastname: Chen
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Wanli
authors.initials: W
authors.lastname: Ma
authors.forename: Jianbao
authors.initials: J
authors.lastname: Xin
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000401:mortality / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D009154:Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D017594:Publication Bias; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins