Sensitivity and Specificity of Mass Screening for Gastric Cancer Using the Measurement of Serum Pepsinogens

The aim of this study was to estimate the validity of mass screening for gastric cancer using serum pepsinogens (PG test). The study subjects were 4876 workers aged from 40 to 61 years old. Sera were obtained at the time of the health checkup and serum pepsinogen levels (PG I and PG II) were measured at the same time. PG I < 50 ng/ml and PG I/PG II ratio < 3.0 were adopted as the criteria for a positive result for the PG test. PG test‐positive subjects were examined, in principle, by endoscopy. Furthermore, all the subjects were followed up for a year to check for occurrence of gastric cancer. Among the total subjects, 911 (18.7%) were positive for the PG test and 650 (71.4%) among the positive subjects underwent further examinations, which revealed 11 cases of gastric cancer. Seven gastric cancer cases were diagnosed during the follow‐up period within one year after the PG test. Six out of the 7 cancer cases had been negative in the PG test. When the results of one year's follow‐up from the time of screening were defined as the gold standard, the sensitivity and specificity of the PG test were estimated at 66.7% and 81.5%, respectively. The authors conclude that the validity of the PG test as a mass screening method may be comparable to that of X‐ray screening, if optimum criteria of a positive test are selected.