title: Tumour markers in rheumatoid arthritis-associated interstitial lung disease.
abstract: OBJECTIVE
  Interstitial lung disease (ILD) is the most common pulmonary extra-articular manifestations of rheumatoid arthritis (RA), but the pathogenesis of RA-ILD is unknown. The purpose of this study was to investigate the tumour markers levels in patients of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) and to explore the diagnostic value of serum tumour markers for RA-ILD.
  
  
  METHODS
  Twenty-eight patients with RA-ILD and 83 patients with RA only were included. Serum levels of tumour markers carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 15-3, CA125, and CA19-9 were measured.
  
  
  RESULTS
  Tumour markers CA15-3, CA125 and CA19-9 were increased in RA-ILD patients compared with RA without ILD patients. Logistic regression analysis revealed that older age (OR=1.06, 95% CI=[1.02-1.11]) and higher CA125 (OR=1.03, 95% CI=[1.01-1.05]) related to the increased risk of RA-ILD. ROC curve analysis showed the relationship between CA125 and RA-ILD was moderate (area under ROC curve (AUC)=0.78, 95% CI=[0.68-0.88]). In addition, CA125 levels above the normal reference (<35 U/ml) raised the risk of RA-ILD (OR=6.00, 95% CI=[2.37-15.16]).
  
  
  CONCLUSIONS
  RA patient with older age and elevated tumour markers especially CA125 levels should be evaluated to check whether there is a potential of ILD.
authors.affiliation: Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Radiology, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Xing-Ju
authors.initials: XJ
authors.lastname: Zheng
authors.affiliation: Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Ji
authors.affiliation: Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China. liangzongan@163.com.
authors.forename: Zong-An
authors.initials: ZA
authors.lastname: Liang
authors.affiliation: Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Bin-Miao
authors.initials: BM
authors.lastname: Liang
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D019540:Area Under Curve; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000175:diagnosis; D014408:Biomarkers, Tumor / Q000097:blood*; D018394:CA-125 Antigen / Q000097:blood; D018395:CA-19-9 Antigen / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D016015:Logistic Models; D017563:Lung Diseases, Interstitial / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; C060192:MUC1 protein, human; D018396:Mucin-1