Objective: To study the correlation between serum pepsinogen (PG) level and gastric mucosal changes of the residents who live in the high incidence area of gastric cancer, and investigate the value of serum PG level in screening for chronic atrophic gastritis (CAG) and gastric cancer (GC).
Methods: Serum PG level was detected with time resolved fluorescence immunoassay (TRFIA). The correlation between serum PG level and gastric mucosal changes was analyzed through endoscopic biopsy and pathological examination in 720 adult residents.
Results: The median serum PG I, PG II level and PG I / PG II ratio in 30 healthy residents with normal gastric mucosa was 172.0 microg/L, 9.6 microg/L and 17.5, respectively. The median serum PG I level of GC patients was significantly lower than that of chronic gastritis patients, gastric ulcer (GU) patients and local healthy residents (P < 0.05). The median PG I level of GU patients was significantly higher than that of the healthy resident group and the other groups (P <0.05). Serum PG II level in CAG, GC and GU groups were all significantly higher than that in CSG and healthy resident group (P <0.05). The PG I/PG II ratio in CAG or GC patients was significantly lower than that in the other groups (P < 0.05). The sensitivity and specificity of serum PG I < or = 60 microg/L for screening CAG or GC was 19.7% and 95.5% respectively, which were 34.7%, 89.3% for PG I/PG II < or =6, and 14.1%, 97.3% for PG I < or =60 microg/L + PG I /PG II < or =6. None in GU group was found to have serum PG I < or =60 microg/L. The median serum PG I level and PG I /PG II ratio in chronic gastritis (including CSG and CAG) with intestinal metaplasia were significantly lower than that of healthy resident group (P < 0.05). The sensitivity and specificity for screening of intestinal metaplasia were 16.6% and 92.9% by PG I < or =60 microg/L; 25.6% and 80.4% by PG I/PG II < or =6; 11.9% and 93.9% by PG I < or =60 microg/L + PG I/ PG II < or = 6.
Conclusion: Serum pepsinogen level of the residents in the high incidence area of gastric cancer is closely correlated with the pathological changes of gastric mucosa. Though the sensitivity of serum pepsinogen level is relatively lower in the screening for chronic gastritis, gastric cancer and intestinal metaplasia, the specificity was quite high. PG I < or = 60 microg/L may be usful in differential diagnosis of gastric cancer from gastric ulcer.