幽门螺杆菌与胃癌的关系

Helicobacter Pylori and Gastric Cancer

本文报道1994年在福建长乐进行的大规模胃癌防治计划,通过胃镜、血液检查及问卷检查,发现30例胃癌及214例消化性溃疡,幽门螺杆菌的感染率在各类人群中为67％至94％不等。在年龄36岁至65岁组中,长乐地区幽门螺杆菌的感染率明显高于香港,无论是幽门螺杆菌的感染者或非感染者,胃窦肠上皮化生发现率在长乐都高于香港,在长乐,胃窦肠上皮化生发现率高于胃体肠上皮化生。长乐及香港的Cag-A阳性菌株与各种胃疾病有明显关系,在无症状组中,Cag-A阳性菌株在长乐占72％,明显高于香港的29％。Cag-A阳性菌株与胃炎、粘膜萎缩、肠上皮化生、不典型增生和胃癌有明显关系。问卷发现多喝茶及多进食蔬菜有保护作用,而抽烟及饮酒人群或进食咸鱼有较多机会形成胃癌。

Mortality of gastric cancer in Changle is one of the highest in the World. Alarge prospective cancer prevention study was started in 1994. Individuals were invited to participate in the screening program consisted of endoscopy to look for cancer, blood taking and questionnaires. Serological tests for Helicobacter pylori (Hp) and cagA status and histological assessment of biopsies were performed. Similar study was carried out in Hong Kong for comparison. Results: 30 gastric cancers and 214 peptic ulcers were discovered in the endoscopic screening project. Seroprevalence of Hp ranged from 67% to 94% in various asymptomatic or disease groups. In age groups between 36 to 65, the Hp seroprevalences in Changle were significantly higher than those in Hong Kong. Significantly higher prevalence of antral intestinal metaplasia was found in Changle, both in Hp and non-Hp carriers. In Changle, intestinal metaplasia was more prevalent in the antrum than corpus. Prevalence of CagA-bearing strains were associated with various peptic disease both in Changle and Hong Kong, but asymptomatic individuals in Changle has significantly higher prevalence (72%) compared to those in Hong Kong (29%, P<0.001). CagA-bearing strains were also associated with pre-malignant lesions like chronic atrophic gastritis, intestinal metaplasia, dysplasia and cancer in Changle. Dietary questionnaires revealed that tea drinking and fresh vegetable has protective effect while smoking and alcohol and salted fish consumption increased the risk of all pre-malignant lesion. Conclusions: This large scale cohort study confirmed the association between Hp and various peptic diseases and gastric cancer in Changle. Various risk factors to gastric cancer, such as prevalence of Hp and CagA-bearing strains and antral intestinal metaplasia, were significantly higher in Changle than in Hong Kong, pointing to their importance in gastric carcinogenesis.