广西医学

目的分析血清胃泌素⁃17（G⁃17）、胃蛋白酶原（PG）Ⅰ、PGⅡ 及PGⅠ/PGⅡ 值（PGR）在胃癌筛查中的应用价值，并探讨基于杭州人群特征所构建的ABC法（杭州ABC法）对胃癌的筛查效果。方法（1）确立阶段：选取杭州市两家医院的1 747名健康体检者（胃癌高风险人群），对其进行血清G⁃17、PGⅠ、PGⅡ 水平检测及胃镜检查。通过受试者工作特征曲线确定各指标诊断胃癌的最佳截断值，并评估其单独与联合应用的诊断效能。（2）验证阶段：选取杭州市多家医院的22 133名健康体检者，对其进行血清G⁃17、PGⅠ、PGⅡ 水平检测。分别应用新ABC法与杭州ABC法对所有对象进行风险分层，对于中高危人群建议胃镜检查，对低危人群进行5年随访。比较两种方法的胃癌检出率及诊断效能。结果（1）1 747名健康体检者中，59名诊断为胃腺癌（胃癌组），1 608名不存在胃肿瘤（非胃肿瘤组）。胃癌组的血清PGⅠ水平、PGR低于非胃肿瘤组，血清G⁃17水平高于非胃肿瘤组（P<0.05），但两组PGⅡ水平差异无统计学意义（P>0.05）。（2）确立阶段：纳入G⁃17、PGⅠ、PGR进行分析，三者诊断胃癌的最佳截断值分别为9.78 pmol/L、75.53 μg/L、4.98。采用单一指标诊断胃癌时，仅PGR的灵敏度>80%，且曲线下面积（AUC）相对更大（0.706）。采用联合指标诊断胃癌时，PGR联合G⁃17、PGR联合PGⅠ、PGR联合G⁃17和PGⅠ诊断胃癌时的AUC分别为0.690、0.625、0.634，灵敏度分别为94.9%、71.2%、96.6%。其中，PGR联合G⁃17灵敏度高于单一PGR，且其AUC大于PGR联合G⁃17和PGI（P<0.05）。最终基于PGR、G⁃17建立杭州ABC法（PGR≤4.98或G⁃17≥9.78 pmol/L）。（3）验证阶段：杭州ABC法诊断胃癌的灵敏度（69.23%）、AUC（0.708）优于新ABC法（分别为50.77%、0.629）。结论用于胃癌筛查时，PGR是诊断效能较优的单一血清学指标，与G⁃17联合可进一步提升诊断价值。基于杭州地区人群特征调整截断值后建立的杭州ABC法，其筛查效能优于新ABC法，更适用于杭州地区胃癌的早期筛查与风险分层。

Objective To analyze the application value of serum gastrin 17 (G⁃17), pepsinogen (PG)Ⅰ, PGⅡ, and PGⅠ⁃to⁃PGⅡ ratio (PGR) in gastric cancer screening, and to explore the effect of gastric cancer screening based on Hangzhou population characteristics⁃constructed ABC method (Hangzhou ABC method). Methods (1) Establishment stage: a total of 1747 healthy check⁃up individuals (high⁃risk population for gastric cancer) were selected from two Hangzhou hospitals. All individuals underwent examination of serum G⁃17, PGⅠ and PGⅡ levels, and gastroscopy. The optimal cut⁃off values for various indices in diagnosing gastric cancer were determined using receiver operating characteristic curves, and the diagnostic performance when used them alone or in combination was evaluated. (2) Validation stage: a total of 22 133 healthy check⁃up individuals from Hangzhou multiple hospitals were selected, and their levels of serum G⁃17, PGⅠ and PGⅡ were detected. Risk stratification was performed on all research subjects using the new ABC method and the Hangzhou ABC method, and gastroscopy was recommended for medium⁃ and high⁃risk groups, while the low⁃risk group was followed up for 5 years. Gastric cancer detection rate and diagnostic performance were compared between the two methods. Results (1) Among 1747 healthy check⁃up individuals, 59 were diagnosed with gastric adenocarcinoma (the gastric cancer group) and 1608 had no gastric tumors (the non⁃gastric tumor group). Serum PGⅠ level and PGR in the gastric cancer group were lower than those in the non⁃gastric tumor group, while serum G⁃17 level was higher than that in the non⁃gastric tumor group (P<0.05). However, no statistically significant difference in PGⅡ level was observed between the two groups (P>0.05). (2) Establishment stage: G⁃17, PGⅠ, and PGR were enrolled in the analysis. The optimal cut⁃off values for the three in diagnosing gastric cancer were 9.78 pmol/L, 75.53 μg/L, and 4.98, respectively. When using a single indicator for gastric cancer diagnosis, only PGR achieved a sensitivity >80%, with a relatively larger area under the curve (AUC) of 0.706. When using combined indicators, the AUC for PGR combined with G⁃17, PGR combined with PGⅠ, and PGR combined with G⁃17 in diagnosing gastric cancer were 0.690, 0.625, and 0.634, with sensitivities of 94.9%, 71.2%, and 96.6%, respectively. Among these, the sensitivity of PGR combined with G⁃17 was higher than that of PGR alone, and its AUC was greater than that of PGR combined with G⁃17 and PGⅠ (P<0.05). Ultimately, based on PGR and G⁃17, the Hangzhou ABC method (PGR ≤4.98 or G⁃17 ≥9.78 pmol/L) was established. (3) Validation stage: the Hangzhou ABC method demonstrated superior sensitivity (69.23%) and AUC (0.708) for gastric cancer diagnosis compared to the new ABC method (50.77% and 0.629, respectively). Conclusion For gastric cancer screening, PGR is the single serological indicator with superior diagnostic performance, and its combination with G⁃17 further enhances diagnostic value. The Hangzhou ABC method, established using cut⁃off values adjusted for local population characteristics in the Hangzhou area, demonstrates superior screening performance as compared with the new ABC method, and is more suitable for early gastric cancer screening and risk stratification in the Hangzhou area.