title: Possibility of multivariate function composed of plasma amino acid profiles as a novel screening index for non-small cell lung cancer: a case control study.
abstract: BACKGROUND
  The amino-acid balance in cancer patients often differs from that in healthy individuals, because of metabolic changes. This study investigated the use of plasma amino-acid profiles as a novel marker for screening non-small-cell lung cancer (NSCLC) patients.
  
  
  METHODS
  The amino-acid concentrations in venous blood samples from pre-treatment NSCLC patients (n = 141), and age-matched, gender-matched, and smoking status-matched controls (n = 423), were measured using liquid chromatography and mass spectrometry. The resultant study data set was subjected to multiple logistic regression analysis to identify amino acids related with NSCLC and construct the criteria for discriminating NSCLC patients from controls. A test data set derived from 162 patients and 3,917 controls was used to validate the stability of the constructed criteria.
  
  
  RESULTS
  The plasma amino-acid profiles significantly differed between the NSCLC patients and the controls. The obtained model (including alanine, valine, isoleucine, histidine, tryptophan and ornithine concentrations) performed well, with an area under the curve of the receiver-operator characteristic curve (ROC_AUC) of >0.8, and allowed NSCLC patients and controls to be discriminated regardless of disease stage or histological type.
  
  
  CONCLUSIONS
  This study shows that plasma amino acid profiling will be a potential screening tool for NSCLC.
authors.affiliation: Department of Thoracic Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Maeda
authors.forename: Masahiko
authors.initials: M
authors.lastname: Higashiyama
authors.forename: Akira
authors.initials: A
authors.lastname: Imaizumi
authors.forename: Tomio
authors.initials: T
authors.lastname: Nakayama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Daimon
authors.forename: Minoru
authors.initials: M
authors.lastname: Yamakado
authors.forename: Fumio
authors.initials: F
authors.lastname: Imamura
authors.forename: Ken
authors.initials: K
authors.lastname: Kodama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000175:diagnosis / Q000473:pathology; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008175:Lung Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000473:pathology; D008297:Male; D008403:Mass Screening / Q000379:methods*; D055432:Metabolomics; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012372:ROC Curve; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D055815:Young Adult
chemical_list: D000596:Amino Acids; D014408:Biomarkers, Tumor