目的：评估胃蛋白酶原筛查试验在无症状胃癌高危人群中检出慢性萎缩性胃炎（chronic atrophic gastritis,CAG）的价值。方法：选取上海石门二路街道社区和南京西路街道社区中无症状的胃癌高危居民,测定其幽门螺杆菌抗体、血清胃蛋白酶原（pepsinogen,PG）Ⅰ和Ⅱ水平,并行内镜检查、胃黏膜活检,根据胃黏膜病理结果中CAG的累及范围分为无萎缩组、胃窦为主萎缩组、胃体为主萎缩组和胃广泛萎缩组4组。结果：本研究共入组居民178人,血清PGⅠ、PGⅡ水平在各组间差异无统计学意义,而与无萎缩组及胃窦为主萎缩组相比较,胃广泛萎缩组及胃体为主萎缩组的胃蛋白酶原比值（pepsinogen ratio,PGR）（PGⅠ/PGⅡ）显著降低（P<0.05)。当PGR临界值选择≤5.16时,检出胃广泛萎缩的灵敏度和特异度分别达到91.8%和61.9%,受试者工作特征曲线的曲线下面积为0.794;当临界值选择≤6.43时,诊断胃体为主萎缩性胃炎灵敏度和特异度分别达到78.7%和65.5%,曲线下面积达到0.750。结论：血清PGR在检出累及胃体的CAG中具有较高灵敏度和特异度,有望作为在胃癌高危人群中筛查CAG的血清学标志物。

Objective: To evaluate the value of measurement of serum pepsinogen(PG) for the screening of chronic atrophic gastritis(CAG) in gastric cancer high risk people. Methods: A symptomatic subjects with high risk for gastric cancer lived in Shanghai central urban area were enrolled to measure serum PG, Helicobacter pylori antibody and conduct endoscopy and biopsy. According to histological results, CAG were divided to no atrophy group, antrum predominant group, corpus predominant group and entire stomach gastricatrophy group. Results: Of the 178 cases enrolled, corpus predominant group and entire stomach group exhibited a significantly lower PGR（PGⅠ∶Ⅱ ratio）when compared with the no atrophy group and antrumpredominant group (P<0.05). The cut-off value of PGR ≤5.16 demonstrated a sensitivity of 91.8%, specificity of 61.9% and area under the receiver operating characteristic curve 0.794 in detecting entire stomach gastric atrophy. The cut-off value of PGR ≤6.43 demonstrated a sensitivity of 78.7%, specificity of 65.5% and area under the receiver operating characteristic curve 0.750 in detecting entire stomach gastric atrophy. Conclusions: Serum PGR is a sensitive and specific marker for detecting corpus involved CAG. PGR might be potentially used as a non-invasive biomarker for detecting CAG among population with high risk for gastric cancer.