Screening markers for chronic atrophic gastritis in Chiapas, Mexico.

Intestinal-type gastric adenocarcinomas usually are preceded by chronic atrophic gastritis. Studies of gastric cancer prevention often rely on identification of this condition. In a clinical trial, we sought to determine the best serological screening method for chronic atrophic gastritis and compared our findings to the published literature. Test characteristics of potential screening tests (antibodies to Helicobacter pyloni or CagA, elevated gastrin, low pepsinogen, increased age) alone or in combination were examined among consecutive subjects enrolled in a study of H. pylori and preneoplastic gastric lesions in Chiapas, Mexico; 70% had chronic atrophic gastritis. English-language articles concerning screening for chronic atrophic gastritis were also reviewed. Sensitivity for chronic atrophic gastritis was highest for antibodies to H. pylori (92%) or CagA, or gastrin levels >25 ng/l (both 83%). Specificity, however, was low for these tests (18, 41, and 22%, respectively). Pepsinogen levels were highly specific but insensitive markers of chronic atrophic gastritis (for pepsinogen I <25 microg/l, sensitivity was 6% and specificity was 100%; for pepsinogen I:pepsinogen II ratio <2.5, sensitivity was 14% and specificity was 96%). Combinations of markers did not improve test characteristics. Screening test characteristics from the literature varied widely and did not consistently identify a good screening strategy. In this study, CagA antibodies alone had the best combination of test characteristics for chronic atrophic gastritis screening. However, no screening test was both highly sensitive and highly specific for chronic atrophic gastritis.     

Gastric cancer screening using the serum pepsinogen test method

The current status of gastric cancer screening, worldwide, as well as in Japan, using the serum pepsinogen test method, was reviewed. We performed a metaanalysis of sensitivity and specificity results from 42 individual studies (27 population-based screening studies: n = 296 553 and 15 selected groups: n = 4 385). Pooled pairs of sensitivity and false-positive rates (FPr) for pepsinogen I level ≤ 70 ng/ml; pepsinogen I/II ratio ≤ 3, had a sensitivity of 77%/FPr27%. The positive predictive value varied between 0.77% and 1.25%, and the negative predictive value varied between 99.08% and 99.90%. Therefore, we concluded that the definition of the pepsinogen test should include the pepsinogen I/II ratio, as consistency was obtained for both the population-based studies and the selected groups for those studies that used pepsinogen I serum levels together with the pepsinogen I/II ratio for screening for gastric cancer in high-incidence regions other than Japan. Individuals testing positive for extensive atrophic gastritis by serum pepsinogen levels undergo endoscopic examination to test for the presence of gastric cancer. We should increase the efficacy and cost-effectiveness of the gastric cancer screening system, by the identification of groups, at low-risk, as well as those at high-risk, of developing gastric cancer, using a combination of assays of serum Helicobacter pylori antibody titers and the concentration of pepsinogen I and II. In conclusion, the pepsinogen test method can be used as a screening test for high-risk subjects, rather than as a tool for screening for cancer itself. I hope that this pepsinogen test method will become a world standard for gastric cancer prevention in the near future, in other countries, as well as in Japan.     

Clinical significance of pepsinogen A isozymogens, serum pepsinogen A and C levels, and serum gastrin levels

Gastric mucosal pepsinogen A phenotype, serum pepsinogen A level, serum pepsinogen C level, serum pepsinogen A/pepsinogen C ratio, and serum gastrin level were evaluated as potential markers for gastric cancer or its precursors in 19 healthy volunteers and 341 patients from the gastroscopy program. Gastric cancer, atrophic gastritis, and intestinal metaplasia of the stomach were associated with pepsinogen A phenotypes, characterized by an intense fraction 5, and with a low serum pepsinogen A level (less than 25 micrograms/l), a low serum pepsinogen A/pepsinogen C ratio (less than 1.5), and a high serum gastrin level (greater than 79 ng/l). The specificity of pepsinogen A phenotypes with an intense fraction 5 for gastric cancer or its precursors was 95.1% with a sensitivity of 20.4%. The sensitivity and specificity of the noninvasive tests were evaluated with the receiver operating characteristic. For clinical purposes, a serum pepsinogen A/pepsinogen C ratio less than 1.8 is the most suitable test, with a sensitivity of 74% and a specificity of 76% for gastric cancer or its precursors, with a reference population of patients with benign gastric disorders. However, the sensitivity and specificity of the single or combined tests are too low for population screening purposes.     

CONTRASTIVE STUDY OF THE TISSUE EXPRESSION AND SERUM CONCENTRATION OF PEPSINOGEN C IN GASTRIC MUCOSA DISEASES

Objective： To estimate the practical values of pepsinogen C （PGC） dynamic expression and the levels of serum pepsinogens in gastric cancer screening and diagnosis. Methods： 129 cases gastric mucosa biopsies and serum specimens were examined. The expression of PGC in stomach mucosa was detected by immunohistochemistry. The serum concentration of pepsinogen A （sPGA） and pepsinogen C （sPGC） were determined by ELISA. Results： The positive rate of PGC antigen expression decreased in superficial gastritis （100%）, gastric ulcer or erosion （80.00%）, atrophic gastritis （34.48%） and gastric cancer （11.43%） in sequence （P〈0.05）. There was no statistics difference in concentration of sPGA and sPGC among the above 4 groups. The ratio of sPGA/sPGC decreased in superficial gastritis, gastric ulcer or erosion, atrophic gastritis and gastric cancer in sequence （P〈0.05）. There was specific correlation between the expression of PGC in stomach mucosa and the levels of sPGA/sPGC ratio in serum （rs =0.297, P=0.001）. Conclusion： Tissue expression of PGC has close relationship with different gastric diseases. The ratio of sPGA/sPGC is relative with the tissue expression of PGC antigen and may be a convenient and economic maker in screening and diagnosis of gastric cancer.     

Validity of serum pepsinogen levels and quininium resin test combined for gastric cancer screening

BACKGROUND: To investigate the feasibility of combining several serum markers into a valid serum screening tool for gastric cancer, we performed a study evaluating the association between gastric cancer and precancerous conditions and a blood test for gastric acidity (the blood quininium resin test [QRT]) combined with serum pepsinogen levels. METHODS: We performed immunoradiometric assays of serum pepsinogen I (PG I), II (PG II) levels, and QRT's in 10 endoscopically normal subjects, in 20 patients with chronic atrophic gastritis, and in 13 patients with biopsy-confirmed gastric adenocarcinoma. RESULTS: Serum PG I, II levels, I/II ratio were significantly different among normal, gastritis, and cancer patients. Serum PG I/II ratios were much lower in cancer patients. Serum quinine levels by QRT were correlated with PG I/II ratio (rs=0.39, p<0.01). Age was negatively correlated both with PG I/II ratio (rs=-0.58, p<0.01) and serum quinine level (rs=-0.45, p<0.01). The screening using serum PG levels was more valid (sensitivity of 69%, specificity of 77%) than that using QRT alone. The combination of serum PG levels and QRT increased specificity for detecting gastric cancer to 87% without altering sensitivity. CONCLUSION: Although blood QRT is a useful addition to other serum screening tests for gastric cancer, these tests alone are not sufficiently accurate as screening tools for gastric cancer.     

Effect of Helicobacter pylori infection combined with CagA and pepsinogen status on gastric cancer development among Japanese men and women: a nested case-control study.

BACKGROUND: Although accumulating evidence suggests that Helicobacter pylori plays a role in gastric carcinogenesis, the magnitude of the risk remains uncertain. Aim: We aimed to estimate the magnitude of the risk of gastric cancer associated with H. pylori infection by a large case-control study nested within a prospective cohort. Possible effect modification by CagA status, and serum pepsinogen status, as a marker of atrophic gastritis, was also considered to see its effect on developing gastric cancer. Subjects and METHODS: Subjects (n = 123,576) were followed up from 1990 to 2004; 511 gastric cancer cases matched to 511 controls were used in the analysis. Plasma immunoglobulin G antibody to H. pylori, CagA, and pepsinogen I and II were measured. RESULTS: The adjusted odds ratio (95% confidence interval) of gastric cancer associated with H. pylori infection was 5.1 (3.2-8.0). Assuming all CagA-positive subjects are true H. pylori positives doubled this risk. Atrophic gastritis was also associated with an elevated risk of gastric cancer and the risk increased further with pepsinogen levels. CONCLUSIONS: Subjects with pepsinogen levels indicative of severe atrophic gastritis may need careful examination regularly regardless of H. pylori infection. Those who have other pepsinogen levels but who are H. pylori seropositive are likely to benefit from H. pylori eradication therapy. Considering both the cost and the potential for misclassification that may occur using multiple serologic tests, caution is needed in interpreting or extrapolating these findings into a screening strategy.     

Helicobacter pylori gastritis and serum pepsinogen levels in a healthy population: development of a biomarker strategy for gastric atrophy in high risk groups.

This study aimed to estimate the prevalence and type of chronic gastritis in an asymptomatic working population and to determine whether a combination of serum pepsinogen levels and Helicobacter pylori serology could be used to identify a subgroup with atrophic gastritis at elevated risk of gastric carcinoma. A 10% subsample of 544 male volunteer factory workers aged 18-63 years and participating in a larger study underwent endoscopy and biopsy. Of these men, 29 were seropositive for Helicobacter pylori; all but three (89.7%) had chronic gastritis. Serum pepsinogen A levels increased with progression from a corpus predominant pattern of gastritis through pangastritis to an antral predominant pattern. Nine subjects had corpus atrophy, which was in most cases accompanied by fasting hypochlorhydria and hypergastrinaemia. A combination of pepsinogen A below 80 ng ml-1 and Helicobaceter pylori seropositivity detected corpus atrophy with sensitivity 88.9% and specificity 92.3%. A second screening stage, using a pepsinogen A/C ratio of below 2.5 as a cut-off, resulted in a reduction in numbers requiring further investigation but with some loss of sensitivity (77.8%). Application of this two-stage screening programme to the original sample of 544 workers would have resulted in 11 (2.2%) men being selected for follow-up, excluding 25 (5.1%) false negatives. Our results suggest that a combination of serum pepsinogen levels and Helicobacter pylori serology could be useful as a biomarker strategy for detection of individuals at increased risk of gastric carcinoma and for non-invasive investigation of the natural history of Helicobacter pylori gastritis.     

胃癌高发区居民血清胃蛋白酶原水平与胃黏膜病变的关系

目的探讨胃癌高发区居民血清胃蛋白酶原（PG）水平与胃黏膜病变的关系,以及血清PG检测在胃癌和慢性萎缩性胃炎（CAG）筛查中的应用价值。方法采用时间分辨荧光免疫分析法（TRFIA）进行PG检测,与内镜活检、病理形态学观察结果相结合,对比分析胃癌高发区720例接受胃镜检查的当地居民血清PGⅠ、PGⅡ水平和胃黏膜病变的关系。结果胃黏膜正常组血清PG Ⅰ、PGⅡ和PGⅠ／PGⅡ比值的中位数分别为172．0μg／L、9．6μg／L和17．5。胃癌组血清PGⅠ水平明显低于慢性胃炎组、胃黏膜正常组和胃溃疡（GU）组（P均〈0．05）。GU组血清PGⅠ水平明显高于其他各组（P均〈0．05）。CAG组、胃癌组和GU组血清PGⅡ水平均明显高于慢性浅表性胃炎（CSG）组和胃黏膜正常组（P均〈0．05）。CAG组和胃癌组血清PGⅠ／PGⅡ比值明显低于其他组（P均〈0．05）。PGⅠ≤60μg／L对CAG或胃癌检出的灵敏度和特异度分别为19．7％和95．5％;而PGⅠ／PGⅡ比值≤6的检出灵敏度和特异度分别为34．7％和89．3％;PGⅠ≤60μg／L且PGⅠ／PGⅡ比值≤6的灵敏度和特异度分别为14．1％和97．3％。慢性胃炎伴肠上皮化生组血清PGⅠ水平和PGⅠ／PGⅡ比值明显低于正常组,而PGⅡ则明显增高（P〈0．05）。PGⅠ≤60μg／L、PGⅠ／PGⅡ比值≤6、PGⅠ≤60μg／L且PGⅠ／PGⅡ比值≤6对肠上皮化生检出的灵敏度分别为16．6％、25．6％和11．9％,特异度分别为92．9％、80．4％和93．9％。结论胃癌高发区居民血清PG水平与胃黏膜病变密切相关。血清PG异常作为CAG、胃癌及肠上皮化生病变筛查指标的灵敏度不太高,但特异度高。血清PGⅠ≤60μg／L可作为鉴别诊断胃癌与GU的一个辅助指标。     

A Pilot Study for a Randomized Controlled Trial to Prevent Gastric Cancer in High-risk Japanese Population: Study Design and Feasibility Evaluation

Observational epidemiological studies suggest that some nutrients reduce the risk of gastric cancer and that individuals with atrophic gastritis are at high risk of developing gastric cancer. One possible measure for gastric cancer prevention is therefore nutritional supplementation for the high risk group. Before recommending this strategy for the general public, however, a randomized controlled trial (RCT) is necessary. To evaluate the feasibility of an RCT, the authors conducted a pilot study using recipients of a health check-up program in a general hospital in Japan. The subjects who were asked to participate in the trial had been diagnosed as having atrophic gastritis on the basis of serum pepsinogen I <70 ng/ml and the ratio of pepsinogen I to II <3.0. They were requested to ingest double-blinded capsules containing different levels of vitamin C and β-carotene every day. Out of the 219 subjects (118 males, 101 females) who were eligible for the study and had the required pepsinogen measurement, 90 (41%) met the criteria for atrophic gastritis. Among them, 55 (61%) (35 males, 20 females) gave their informed consent to participate in the RCT. Fifty-four participants completed a 3-month course of supplementation, and all of them agreed to a 5-year supplementation period. The authors concluded that an RCT using double-blinded nutritional supplements and targeting apparently healthy individuals is feasible in an intervention study for cancer prevention in Japan.     

The Significance of Low Serum Pepsinogen Levels to Detect Stomach Cancer Associated with Extensive Chronic Gastritis in Japanese Subjects

Serum pepsinogen levels were measured in 137 stomach cancer patients and compared with those of 288 normal cancer-free subjects. The serum pepsinogen levels of stomach cancer patients, especially pepsinogen I and the pepsinogen I/pepsinogen II ratio were significantly lower than those of normal controls and correlated well with the extent of chronic gastritis associated with the cancerous stomach. These results were in good accordance with the results of previous studies indicating that the cancer derived from the stomach where chronic gastritis/intestinal metaplasia is extensive. The high sensitivity and specificity of this non-invasive serum test to detect chronic gastritis suggested the possibility of its application to the mass screening of stomach cancer.     

The significance of low serum pepsinogen levels to detect stomach cancer associated with extensive chronic gastritis in Japanese subjects

Serum pepsinogen levels were measured in 137 stomach cancer patients and compared with those of 288 normal cancer-free subjects. The serum pepsinogen levels of stomach cancer patients, especially pepsinogen I and the pepsinogen I/pepsinogen II ratio were significantly lower than those of normal controls and correlated well with the extent of chronic gastritis associated with the cancerous stomach. These results were in good accordance with the results of previous studies indicating that the cancer derived from the stomach where chronic gastritis/intestinal metaplasia is extensive. The high sensitivity and specificity of this non-invasive serum test to detect chronic gastritis suggested the possibility of its application to the mass screening of stomach cancer.     

ABC screening for gastric cancer is not applicable in a Japanese population with high prevalence of atrophic gastritis

A combination of the detection of serum anti-Helicobacter pylori antibody and measurement of the level of serum pepsinogens (PG)s, known as the ABC method, has been used in screening for gastric cancer. The ABC method has been shown to be useful in urban and/or younger populations. The aim of this study was to assess whether this method is applicable for an agricultural population with a high incidence of gastric cancer. In all, 1048 healthy adults (401 men and 647 women) who participated in a mass survey in April 2005 were examined. Their serum samples were tested to determine the prevalence of anti-H. pylori antibody, and the levels of PG I and PG II were also measured to assess the presence of atrophic gastritis. Of the elderly subjects born before 1940, 59.4% were classified into groups C and D, with a high risk for gastric cancer, and only 22.7% were classified into group A, with the lowest risk. Of the middle-aged subjects born in the 1940s and the 1950s, 66.5% were classified into groups B-D. If the ABC method is performed in the mass screening for gastric cancer in this population, a large number of subjects will be identified for further examinations. The applicability of the ABC method should be evaluated before use in the screening for gastric cancer, particularly in an aging population with a high prevalence of H. pylori infection and atrophic gastritis.     

Sister chromatid exchange in gastric cancer, chronic atrophic gastritis and normal control

The frequencies of sister chromatid exchange (SCE) in proven cases of 10 chronic atrophic gastritis and 9 gastric cancer were observed together with 10 cases of normal control. They were (1) chronic atrophic gastritis 6.98 +/- 0.89, (2) gastric cancer 7.49 +/- 0.42 and (3) normal control 5.89 +/- 0.57. Statistically, there was a very significant difference in the SCE frequencies between the gastric cancer and normal control groups (P less than 0.001) and a significant difference between the chronic atrophic gastritis and normal control groups (P less than 0.05). However, the difference between the gastric cancer and the chronic atrophic gastritis was not significant (P greater than 0.05). The similarity in the incidence of SCE may offer an evidence for the close relationship theory between gastric cancer and chronic atrophic gastritis.     

Gastric cancer screening of a high-risk population in Japan using serum pepsinogen and barium digital radiography

With the aim of developing more efficient gastric cancer screening programs for use in Japan, we studied a new screening program that combines serum pepsinogen (PG) testing and barium digital radiography (DR). A total of 17 647 middle-aged male subjects underwent workplace screening over a 7-year period using a combination of PG testing and DR. This program's effectiveness, as well as other characteristics of the program, was analyzed. Forty-nine cases of gastric cancer were detected (comprising 88% early cancer cases). The detection rate was 0.28%, and the positive predictive value was 0.85%. The PG test detected 63.3% of cases, DR detected 69.4% of cases, and both tests were positive in 32.7% of cancer cases. The two methods were almost equally effective, and were considerably more effective than conventional screening using photofluorography. Each screening method detected a distinct gastric cancer subgroup; the PG test efficiently detected asymptomatic small early cancer with intestinal type histology, while DR was efficient at detecting cancers with depressed or ulcerated morphology and diffuse type histology. The cost for the detection of a single cancer was much less than that for conventional screening. In fact, it is possible to further reduce the cost of detecting a single cancer to a cost comparable to that of surgically resecting a single gastric cancer. Thus, it is probable that a highly efficient gastric cancer screening system can be implemented by combining the two screening methods. Such a screening program would be beneficial in a population at high risk for gastric cancer.     

胃癌癌前病变相关标志物的检测

It is confirmed that chronic atrophic gastritis (CAG) which is caused by Helicobacter pylori is the main cause of gastric precancerous lesions. CAG is also the key determinant in gastric cancer risk assessment, which affects pepsinogen and gastrin-17 secretion. Most of the gastric cancer patients with poor prognosis, and non-invasive tools for gastric cancer screening and diagnosis are lacking. Therefore, the early detection of gastric cancer in order to reduce the disease mortality is necessary. Pepsinogen and gastrin-17 are biomarkers of gastric mucosa and gastric antra. The serological testing for the stomach-specific biomarkers offers the possibility to know preneoplastic gastric mucosal conditions.     

Serum pepsinogen levels in gastric cancer patients and their relationship with Helicobacter pylori infection: a prospective study.

BACKGROUND: Our aim was to study the serum pepsinogen levels in gastric cancer patients in our population in relation to histology and the presence of Helicobacter pylori. METHODS: Forty-six patients with gastric cancer and 70 controls were studied prospectively in a 1-year period. Serum levels of pepsinogen I (PG I), pepsinogen II (PG II), and gastrin were measured by radioimmunoassay. RESULTS: The mean PG I levels for cancer patients and controls were 83.5 microg/l and 60.9 microg/l, respectively (P = 0.03), the mean PG II levels were 27.2 microg/l and 12.1 microg/l respectively (P < 0.0001). The PG I/II ratio was significantly lower in cancer patients (P = 0.04) and in those with Helicobacter infection. Serum pepsinogen levels were not affected by any pathological characteristics. Histology showed that the prevalence of chronic gastritis, intestinal metaplasia, and gastric atrophy was 97%, 56%, and 15%, respectively. CONCLUSION: The prevalence of gastric atrophy is low in our population, and serum pepsinogen measurement is not useful as a screening tool for gastric cancer in this population.     

DEK在胃癌组织中的表达及意义

目的 通过检测DEK基因在胃正常黏膜、慢性萎缩性胃炎及胃癌组织中的表达,探讨其在胃癌发病机制中的作用及意义。方法 收集2008年1月至2011年2月昆明医学院第二附属医院和第四军医大学西京医院病理科保存的病理组织石蜡切片,采用免疫组化SP法检测DEK在49例胃正常黏膜、63例慢性萎缩性胃炎及132例胃癌组织中的表达并分析其临床意义。结果 在132例胃癌组织中DEK基因的阳性表达率为78.0％（103／132）,明显高于慢性萎缩性胃炎组织的60.3％（38／63）和正常胃黏膜组织的28.6％（14／49）,差异有统计学意义（P＜0.05）。DEK表达与胃癌组织的分化程度及有无淋巴转移有关（P＜0.05）,但与性别、年龄、肿瘤大小、侵犯深度及TNM分期均无关（P＞0.05）。结论 随着慢性萎缩性胃炎的进展,DEK基因逐步激活,在胃癌组织中出现DEK基因大量激活;DEK基因激活与胃癌发生有关,且与胃癌的组织分化程度和肿瘤转移有一定关系。     

血清PGⅠ、PGⅡ及G-17检测在胃癌及萎缩性胃炎中的诊断价值分析

目的 分析检测血清胃蛋白酶原Ⅰ(PGⅠ)、胃蛋白酶原Ⅱ(PGⅡ)及胃泌素17(G-17)在胃癌及萎缩性胃炎中的诊断价值.方法 选取接受胃镜检查的患者865例,其中浅表性胃炎患者339例作为浅表性胃炎组,萎缩性胃炎患者318例作为萎缩性胃炎组,胃癌患者208例作为胃癌组.采用酶联免疫吸附试验(ELISA)检测3组患者的血清G-17水平;采用胶乳免疫比浊法检测3组患者的血清PGⅠ、PGⅡ水平,并计算胃蛋白酶原比值(PGR);采用单纯取胃体组织做快速尿素酶测定(RUT)法和幽门螺旋杆菌(HP)尿素酶抗体检测试剂盒检测HP值.对3组患者的各指标进行比较,评价其诊断胃癌和萎缩性胃炎的价值.结果 胃癌组患者的PGⅠ水平低于萎缩性胃炎组和浅表性胃炎组(P﹤0.05);萎缩性胃炎组和胃癌组患者的PGⅡ水平低于浅表性胃炎组(P﹤0.05);胃癌组患者的G-17水平高于浅表性胃炎组和萎缩性胃炎组(P﹤0.05);胃癌组患者的PGR值小于浅表性胃炎组和萎缩性胃炎组,萎缩性胃炎组患者的PGR值小于浅表性胃炎组(P﹤0.05).PGⅠ和PGR检测胃癌的灵敏度分别为88.9%、86.9%,特异度分别为73.6%、59.4%;PGⅠ、PGR和G-17检测萎缩性胃炎的灵敏度分别为69.9%、70.8%、66.1%,特异度分别为49.8%、51.4%、64.2%.HP阳性患者的PGⅠ和PGⅡ水平均高于HP阴性患者,PGR值小于HP阴性患者(P﹤0.05).结论 血清检测PG水平的方法在诊断胃癌时的特异度和灵敏度均较高,是胃癌患者诊断的一个重要血清学指标,可用于胃癌的早期诊断.     

Cancer high-risk subjects identified by serum pepsinogen tests: outcomes after 10-year follow-up in asymptomatic middle-aged males.

BACKGROUND: Gastric cancer screening using the pepsinogen filter test is receiving wide recognition in Japan owing to convenience, freedom from discomfort or risk, efficiency, and economy. Because the long-term outcomes of cancer development in extensive atrophic gastritis detected by pepsinogen test are unclear, test-positive and test-negative subjects were investigated in a longitudinal cohort study. METHODS: Subjects comprised 5,209 middle-aged men with measured serum pepsinogen levels who were followed for 10 years. Cancer development based on "atrophy-positive" and "atrophy-negative" criteria used for cancer screening was investigated. RESULTS: During the study, 63 cases of cancer developed in the cohort, representing an incidence rate of 125 per 100,000 person-years. Pepsinogen test screening using the most widely used atrophy-positive criterion (pepsinogen I, < or =70 ng/mL; pepsinogen I/II ratio, < or =3.0) displayed 58.7% sensitivity, 73.4% specificity, and 2.6% positive predictive value. Cancer incidence rate was 276 per 100,000 person-years for the atrophy-positive group and 70 per 100,000 person-years for the atrophy-negative group. Incidence rate was higher in groups fulfilling stricter positive criteria detecting more extensive atrophy, reaching 424 per 100,000 person-years. In addition, 9.2% of atrophy-negative subjects with pepsinogen I of >70 ng/mL and pepsinogen I/II ratio of < or =3.0 (reflecting putative inflammation-based high pepsinogen II level) are at high risk for cancer, particularly diffuse-type cancer, with a cancer incidence rate comparable with atrophy-positive subjects (216 per 100,000 person-years). CONCLUSION: Atrophy-positive subjects by pepsinogen filter test, particularly those fulfilling stricter criteria, and atrophy-negative subjects with low pepsinogen I/II ratio reflecting putative extensive active inflammation constitute populations at high risk for gastric cancer, requiring thorough endoscopic examination.     

Detection of gastric carcinoma‐associated MG7‐Ag by serum immuno‐PCR assay in a high‐risk Chinese population,with implication for screening

To evaluate gastric carcinoma‐associated antigen, MG7‐Ag, for detection of gastric cancer in a high‐risk population, a population‐based screening of gastric cancer was conducted in Linqu County, Shandong Province, China. In 2002 and 2003, a total of 2,710 participants aged 35–65 years received an endoscopic examination with 5 biopsies taken from standard sites with pathological diagnosis, and serum samples were collected to detect MG7‐Ag by serum‐based Immunopolymerase chain reaction (PCR) assay. The sensitivity and specificity of MG7‐Ag Immuno‐PCR assay in detecting of gastric cancer were assessed. Of 2,710 participants, 148 (5.46%) were determined to be MG7‐Ag positive. The sensitivity of MG7‐Ag Immuno‐PCR assay for the detection of gastric cancer was 77.5% (31 of 40 gastric cancer cases), the specificity was 95.62% (2,553 of 2,670 nongastric cancer subjects) and the accuracy was 73.12%. A total of 24 gastric cancer cases were in Stage I or II, of which 17 (70.8%) were MG7‐Ag positive. However, the proportion of MG7‐Ag positivity in subjects with superficial gastritis, chronic atrophic gastritis, intestinal metaplasia, indefinite dysplasia or dysplasia was ranged from 3.00% to 5.61% in comparison with 77.5% in those with gastric cancer. Our findings suggest that MG7‐Ag was a sensitive and specific serum biomarker and may have a potential for gastric cancer screening in the high‐risk population.