幽门螺杆菌与胃癌发生进程的10年队列研究

目的 探讨幽门螺杆菌（Hp）在胃癌发生进程中的作用。方法 采用整群随机抽样方法,在胃癌高发区山东省临朐县选择14个自然村,对35-64岁的自然人群进行胃镜普查和血清学检验：取胃黏膜活检组织进行病理学诊断,用酶联免疫吸附法检测Hp抗体。随访5年和10年后,分别再对该人群进行胃镜复查。随访期间对观察对象中无论是自然发生还是胃镜复查发现的胃癌病例均进行登记。结果 经10年随访,共获得符合研究条件的观察对象2469名。随访期间有58例发生胃癌,其中1603名Hp感染阳性者中发生44例（2．74％）,866名Hp感染阴性者中发生14例（1．62％）。Hp感染阳性者发生胃癌的危险性显著高于Hp感染阴性者比值比（OR）=1．871,95％可信区间（CI）：1．012—3．459]。基线正常或浅表性胃炎（SG）组Hp感染阳性者与阴性者向胃癌癌前病变转化和继续发展进度比较,差异无统计学意义（P〉0．05）。而基线萎缩性胃炎（CAG）组Hp感染阳性者胃癌癌前病变的发展速度明显快于阴性者（P〈0．01）;且该组Hp感染阳性者的胃癌发生率（7／615）也明显高于Hp感染阴性者（0／470,P=0．019）。经10年随访,虽然基线肠上皮化生（IM）组和异型增生（DYS）组Hp感染阳性者的胃黏膜病变重于阴性者（分别为P〈0．05,P〈0．01）,但这两组Hp感染阳性者与阴性者的胃癌发生率非常接近：IM组为17／573和7／224（P=0．907）;DYS组为19／368和7／122（P=0．806）。结论 在胃癌的形成过程中,HP是萎缩性胃炎向更高级癌前病变转化和继续发展的重要促进因素,而且在整个胃癌癌前病变的发展过程中均具有促进作用。HP可能不直接引起胃癌,它与其他致癌因素共同作用促进胃癌的发生。HP对正常或仅为浅表性胃炎的胃黏膜可能没有重要的影响,尚需要做进一步研究。

Helicobacter pylori and the progression of gastric cancer: a 10-year cohort study

Objective To search the role of Helicobacter pylori (H. pylori) in the progression of gastric carcinogenesis. Methods A cohort study was conducted by cluster randomized sampling in Linqu County, a rural area in Shandong Province in northeast China, where the mortality of gastric cancer (GC) is among the highest in the world. In 1989-1990, a gastroscopic examination and serum test was launched among subjects aged 35-64 from 14 randomized villages. Histological diagnosis of gastric mucosa and enzyme-linked immunosorbent assay was used to detect gastric lesions and anti-H. pylori of all participants. A repeated gastroscopic screening was offered to all cohort members in 1994 and 1999 respectively, and all the GC cases, regardless of natural ones or ones by gastroscopy, were registered in the follow-up periods. Results Fifty-eight cases of GC were identified in 2469 subjects during the 10-year follow-up, 44 were observed in 1603 H. pylori-positive persons (2.74%) and 14 in 866 H. pylori-negative persons (1.62%). The incidence rate of GC in H. pylori-positive is significantly higher than in H. pylori-negative (OR=1.871, 95%CI: 1.012-3.459). There was no significant difference in the progression of gastric carcinogenesis between H. pylori-positive and H. pylori-negative (P>0.05) among subjects with normal or superficial gastritis (SG) at baseline. In contrast, the significant difference was found in baseline chronic gastritis (CAG) group (P<0.01), and the GC incidence rate in H. pylori-positive (7/615) is higher than in H. pylori-negative (0/470,P=0.019). The difference of gastric lesions between H. pylori-positive and H. pylori-negative in subjects with intestinal metaplasia (IM) and dysplasia (DYS) at baseline was statistically significant after a 10-year follow-up (P<0.05, P<0.01, respectively), but the GC incidence rate in H. pylori-positive is similar to the rate in H. pylori-negative at the two groups (17/573 and 7/224 in IM group, P=0.907;19/368 and 7/122 in DYS group, P=0.806). Conclusions H. pylori is a key risk factor that prompts the transition from chronic atrophic gastritis to advanced precancerous lesions and influences the whole progression of precancerous gastric lesions. H. pylori, perhaps can not cause GC directly, increases the risk of GC in company with other carcinogens. H. pylori seemingly has no important effect on the development of GC when gastric mucosa is normal or superficial gastritis, but this conclusion is required to be further confirmed.