title: Assessing the diagnostic value of serum Dickkopf-related protein 1 levels in cancer detection: a case-control study and meta-analysis.
abstract: BACKGROUND
  This study aimed to summarize the potential diagnostic value of serum DKK1 levels in cancer detection.
  
  
  METHODS
  Serum DKK1 was measured using enzyme-linked immunosorbent assay in a case-control study. Then we performed a meta-analysis and the pooled sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristic (sROC) curves were used to evaluate the overall test performance.
  
  
  RESULTS
  Serum DKK1 levels were found to be significantly upregulated in gastric cancer as compared to controls. ROC curve analysis revealed an AUC of 0.636, indicating the test has the potential to diagnose cancer with poor accuracy. The summary estimates of the pooled sensitivity, specificity and diagnostic odds ratio in meta-analysis were 0.55 with a 95% confidence interval (CI) (0.53-0.57), 0.86 (95%CI, 0.84-0.88) and 12.25 (95%CI, 5.31-28.28), respectively. The area under the sROC was 0.85. Subgroup analysis revealed that the diagnostic accuracy of serum DKK1 in lung cancer (sensitivity: 0.69 with 95%CI, 0.66-0.74; specificity: 0.95 with 95%CI, 0.92-0.97; diagnostic odds ratio: 44.93 with 95%CI, 26.19-77.08) was significantly higher than for any other cancer.
  
  
  CONCLUSIONS
  Serum DKK1 might be useful as a noninvasive method for confirmation of cancer diagnosis, particularly in the case of lung cancer.
authors.affiliation: Clinical Laboratory, Zhejiang Provincial People's Hospital, Hangzhou, China E-mail : taohouquan2008@aliyun.com and dshuang@zju.edu.cn.
authors.forename: Xiao-Ting
authors.initials: XT
authors.lastname: Jiang
authors.forename: Ying-Yu
authors.initials: YY
authors.lastname: Ma
authors.forename: Kun
authors.initials: K
authors.lastname: Guo
authors.forename: Ying-Jie
authors.initials: YJ
authors.lastname: Xia
authors.forename: Hui-Ju
authors.initials: HJ
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Xu-Jun
authors.initials: XJ
authors.lastname: He
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Huang
authors.forename: Hou-Quan
authors.initials: HQ
authors.lastname: Tao
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis*; D011379:Prognosis; D012372:ROC Curve; D013274:Stomach Neoplasms / Q000097:blood / Q000175:diagnosis*
chemical_list: D014408:Biomarkers, Tumor; C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins