Usefulness and Limitations of a Serum Screening System to Predict the Risk of Gastric Cancer.

Objective The aim of the present study was to evaluate the effectiveness and limitations of a serum screening system for predicting the risk of gastric cancer. Methods Serum pepsinogen I (PG I)/pepsinogen II (PG II) and Helicobacter pylori (HP) antibody levels were measured. Subjects were classified into four groupsaccording to their serological status (the ABC classification system). The grade of atrophic gastritis was assessed endoscopically. We evaluated gastric cancer detection rates according to the ABC classification system and the endoscopic grade of atrophy. Patients Individuals who underwent esophagogastroduodenoscopy (EGD) in a health check were prospectively enrolled in the present study. Results According to the ABC classification system, the gastric cancer detection rates in groups A, B, C, and D were 0.07% (4/6,105), 0.5% (8/1,739), 0.8% (16/2,010), and 1.1% (3/281), respectively. The gastric cancer detection rates in subjects with no atrophy, closed type (C-type) atrophy, and open type (O-type) atrophy were 0% (0/4,567), 0.2% (4/2,581), and 0.9% (27/2,987), respectively. In group A (HP(-)/PG(-)), the proportions of subjects with no atrophy, C-type atrophy, and O-type atrophy were 71.2%, 22.8%, and 6.0%, respectively. In group A, the gastric cancer detection rates in subjects with no atrophy, C-type atrophy, and O-type atrophy were 0%, 0.07%, and 0.8%, respectively. Conclusion The ABC classification system is useful for predicting the risk of gastric cancer. However, this system was limited in group A, which included individuals with a high risk of developing gastric cancer. An endoscopic diagnosis of atrophy may be more effective than the ABC classification system for predicting the risk of gastric cancer.

Simultaneous determination of gastric cancer biomarkers pepsinogen PGI/PGII using element tagged immunoassay coupled with inductively coupled plasma mass spectrometry detection.

OBJECTIVES: In this study, a new immunoassay for the simultaneous determination of pepsinogen I (PGI) and pepsinogen II (PGII) in serum based on element labeling strategy coupled with inductively coupled plasma mass spectrometry (ICP-MS) detection was proposed. METHODS: The sandwich-type immunoassay was used to simultaneously detect PGI and PGII in serum. PGI and PGII were captured by anti-PGI and anti-PGII antibody immobilized on the magnetic beads and then banded with Eu3+ labeled anti-PGI detection antibody and Sm3+ labeled anti-PGII detection antibody, followed by ICP-MS detection. RESULTS: The linear correlation coefficient (R2 ) of PGI and PGII standard curves was .9938 and .9911, with the dynamic range of 0-200 ng/mL and 0-60 ng/mL, respectively. The limit of detection for PGI and PGII was 1.8 ng/mL and 0.3 ng/mL, respectively. The average recovery was 101.41% ± 6.74% for PGI and 101.47% ± 4.20% for PGII. Good correlations were obtained between the proposed method and CLIA (r = .9588 for PGI, r = .9853 for PGII). CONCLUSIONS: We established a mass spectrometry-based immunoassay for the simultaneous detection of PGI and PGII in a single analysis. The element tagged immunoassay coupled with ICP-MS detection has high sensitivity, accuracy, and specificity in clinical serum sample analysis.

[Clinical and laboratory evaluation of efficiency of Helicobacter pylori eradication].

AIM: To assess the efficiency of eradication therapy in long-term period using the main signs of functional activity of gastric mucosa (gastrin-17, pepsinogen I, pepsinogen II) and serum antibodies to H. pylori. MATERIALS AND METHODS: 113 patients with chronic gastritis were examihed using clinical, endoscopic and laboratory-based methods of investigation, including GastroPanel Biohit, Finland. RESULTS: It was observed that after 12 month of successful eradication therapy the titer of IgG to H. pylori did not exceed 60 IU/l, with pepsinogen I and pepsinogen II cut-off values set under 150 microg/l and 15 microg/l respectively. CONCLUSION: The decrease of the titer of IgG to H. pylori and concentrations of pepsinogen I and II can be used as criteria of successful eradication therapy in long-term period.

The use of clinical, histologic, and serologic parameters to predict the intragastric extent of intestinal metaplasia: a recommendation for routine practice.

BACKGROUND: Surveillance of intestinal metaplasia (IM) of the gastric mucosa should be limited to patients at high risk of gastric cancer. Patients with extensive IM are at increased cancer risk; however, the intragastric extent of IM is usually unknown at the time of the initial diagnosis. OBJECTIVE: To assess the predictive value of clinical, histologic, and serologic parameters for the intragastric extent of IM. DESIGN AND SETTING: Prospective, multicenter study. PATIENTS: Eighty-eight patients with a previous diagnosis of IM of the gastric mucosa. INTERVENTION: Surveillance gastroscopy with extensive random biopsy sampling. MAIN OUTCOME MEASUREMENTS: Biopsy specimens were evaluated according to the Sydney classification system. In addition, serologic testing of Helicobacter pylori and cagA status, pepsinogens I and II, gastrin, and intrinsic factor antibodies was performed. The association between the available parameters and extensive IM was evaluated with logistic regression analysis. RESULTS: In 51 patients (58%), IM was present in the biopsy specimens from at least 2 intragastric locations. The most important predictors of extensive IM were a family history of gastric cancer, alcohol use > or = 1 unit/d (1 glass, approximately 10 mL or 8 g ethanol), moderate or marked IM of the index biopsy specimen, and a pepsinogen I to II ratio < 3.0. A simple risk score based on these factors could identify extensive IM in 24 of 25 patients (sensitivity 96%). LIMITATION: A prospective cohort study should confirm the proposed risk stratification. CONCLUSIONS: A risk score of clinical, histologic, and serologic parameters can predict extensive intragastric IM and may serve as a practical tool to select patients for surveillance endoscopy in routine clinical practice.

Electrochemical microdevice with separable electrode and antibody chips for simultaneous detection of pepsinogens 1 and 2.

An electrochemical microdevice with separable electrode and antibody chips has been developed and applied to detect atrophic gastritis-related proteins, pepsinogen 1 (PG1) and pepsinogen 2 (PG2), based on sandwich-type enzyme-linked immunosorbent assays (ELISAs) with horseradish peroxidase (HRP)-labeled antibody. To fabricate the electrochemical device for simultaneous analysis of several proteins, the electrode chip with eight electrode elements was assembled along with an antibody chip with eight cavities containing immobilized anti-PG1 or anti-PG2. The immunoreactions occurring in the cavities of the device were detected simultaneously by amperometry. The labeled HRP in the cavity in the presence of hydrogen peroxide catalyzed the oxidation of ferrocenemethanol (FMA) to FMA+, which was detected electrochemically by the electrode chip. The amperometric responses of respective cavities in the device increased with increasing concentration of PG1 or PG2 of 0-50 ng/ml, ensuring the simultaneous detection of PG1 and PG2. The detection limits for both PG1 and PG2 were 0.6 ng/ml (S/N=2). The electrode chip was recovered easily by disassembling the electrochemical device; thereby, it was used repeatedly, whereas the antibody chip was discarded. No marked decrease in electrochemical responses was detected after repeated use. Reuse of the electrode chip is beneficial to reduce costs of protein analysis.

Expression and clinical significance of pepsinogen C in epithelial ovarian carcinomas.

BACKGROUND: Pepsinogen C (pep C) is a gastric aspartic protease of which is associated with a favorable prognosis in breast cancer. Recently, it has been demonstrated in other tumors of extradigestive origin. STUDY DESIGN: We have analyzed pep C expression in 72 epithelial ovarian carcinomas by immunohistochemistry. RESULTS: Nineteen (26%) tumors stained positively for pep C. Overall this expression was not associated with the clinicopathologic characteristics or with outcome. However, in patients with serum levels of CA 125 less than 35 U/ml, pep C expression identified a group with a more favorable prognosis. CONCLUSION: Pepsinogen C is expressed in a quarter of ovarian carcinomas and might identify a subset of patients with different prognosis.