title: Meta-analysis on the validity of pepsinogen test for gastric carcinoma, dysplasia or chronic atrophic gastritis screening.
abstract: OBJECTIVE
  To assess the validity of the measurement of pepsinogen I and II as a screening test for gastric cancer and pre-malignant lesions, namely low-grade dysplasia, both in the general population and in selected groups of patients.
  
  
  METHODS
  A meta-analysis of sensitivity and specificity results from individual papers on the use of the pepsinogen test. An intrinsic cut-off effect was assumed and a random effect model was used for pooling.
  
  
  RESULTS
  Forty-two data sets were included: 27 (64%) population-based screening studies (n=296,553) and 15 (36%) sets of selected individuals (n=4385). Homogenous sensitivity and diagnostic odds ratio (DOR) estimates were found in studies using both pepsinogen I levels and pepsinogen I/II ratio calculations. Pooled pairs of sensitivity and false positive rates (FPr) for pepsinogen I < or = 70; pepsinogen I/II ratio < or = 3, pepsinogen I < or =50; pepsinogen I/II ratio < or = 3, and pepsinogen I < or = 30; pepsinogen I/II ratio < or = 2, were sensitivity 77%/FPr 27%, sensitivity 68%/FPr 31%, and sensitivity 52%/FPr 84%, respectively. Positive predictive values (PPV) varied between 0.77% and 1.25%, and negative predictive values (NPV) varied between 99.08% and 99.90%. In selected groups, pooling was only possible when considering pepsinogen I < or = 70; pepsinogen I/II ratio < or = 3: giving sensitivity 57%, specificity 80%, PPV 15% and NPV 83%. As for the diagnosis of dysplasia, studies considering pepsinogen I <50; pepsinogen I/II ratio <3 obtained sensitivity 65% and specificity ranging from 74%-85%, both with NPV >95%.
  
  
  CONCLUSIONS
  Pepsinogen test definition should include pepsinogen I/II ratio as consistency was obtained, both in population based studies and in selected groups for those studies that used pepsinogen I serum levels together with pepsinogen I/II ratio for screening for gastric cancer in high-incidence regions other than Japan. Further studies of this test in the management of high-risk patients seem to be worthwhile.
authors.affiliation: Showa University, Tokyo, Japan. mario@med.up.pt
authors.forename: M
authors.initials: M
authors.lastname: Dinis-Ribeiro
authors.forename: G
authors.initials: G
authors.lastname: Yamaki
authors.forename: K
authors.initials: K
authors.lastname: Miki
authors.forename: A
authors.initials: A
authors.lastname: Costa-Pereira
authors.forename: M
authors.initials: M
authors.lastname: Matsukawa
authors.forename: M
authors.initials: M
authors.lastname: Kurihara
mesh_terms: D005189:False Positive Reactions; D005757:Gastritis, Atrophic / Q000175:diagnosis*; D006801:Humans; D008403:Mass Screening / Q000379:methods; D020116:Pepsinogen A / Q000097:blood*; D020115:Pepsinogen C / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000175:diagnosis*
chemical_list: D020115:Pepsinogen C; D020116:Pepsinogen A