Abstract:

Objective To investigate the role of time-resolved fluoroimmunoassay（TRFIA） for detecting plasma pepsinogen（PG） Ⅰ,PGⅡ and pepsinogen Ⅰ/pepsinogen Ⅱ ratio（PGR） in screening ulcer gastric cancer. Methods According to the results of gastroscopy and pathology,547 patients were classified into 72 cases of non-atrophic gastritis,232 cases of non-atrophic gastritis with other pathology,42 cases of atrophic gastritis,82 cases of peptic ulcer,15 cases of intraepithelial neoplasia and 104 cases of gastric cancer [43 cases of ulcer gastric cancer（ulcer gastric cancer group） and 61 cases of other gastric cancers（other gastric cancer group）]. TRFIA and chemiluminescence microparticle immunoassay（CMIA） were used to detect plasma PGⅠ and PGⅡ levels of 447 patients with gastric diseases,and PGR was calculated. Receiver operating characteristic（ROC） curve was used to evaluate the efficiency of PGR in the diagnosis of ulcer gastric cancer. Results The results of PGⅠ and PGⅡ of TRFIA and CMIA were positively correlated（r=0.894 and 0.982,P<0.05）. The results of TRFIA for samples with PGⅠ≥240 ng/mL had poor consistency with CMIA. Compared with peptic ulcer group,plasma PGⅠ level and PGR in gastric cancer group were decreased（P<0.05）,and PGR in ulcer gastric cancer group was decreased（P<0.05）,and plasma PGⅠ level in other gastric cancer group was decreased（P<0.05）. Plasma PGⅡ level and PGR of ulcer gastric cancer group were higher than those of other gastric cancer group（P<0.05）. The area under curve（AUC） of PGR for the diagnosis of ulcer gastric cancer was 0.711. The optimal cut-off value was 18.20,the sensitivity was 72.1%,and the specificity was 70.8%. The AUC for the diagnosis of gastric cancer was 0.797,the optimal cut-off value was 18.37,the sensitivity was 79.8%,and the specificity was 70.8%. Conclusions PG Ⅰ and PG Ⅱ detections by TRFIA have a good correlation with CMIA. The upper detection limit of TRFIA is better than that of CMIA. PGR has certain diagnostic value for ulcer gastric cancer.

Key words: Pepsinogen Ⅰ, Pepsinogen Ⅱ, Pepsinogen Ⅰ/pepsinogen Ⅱ ratio, Time-resolved fluoroimmunoassay, Ulcer gastric cancer, Gastric cancer