Predictive power of serum pepsinogen tests for the development of gastric cancer in comparison to the histologic risk index

Serum gastrin-17 concentration for prediction of upper gastrointestinal tract bleeding risk among peptic ulcer patients

BACKGROUND

Serum gastrin-17 (G-17), pepsinogen I (PGI), and pepsinogen II (PGII) concentrations regulate gastric acid secretion, and hypersecretion of gastric acid increases the risks of peptic ulcer and upper gastrointestinal bleeding. These associations suggest that serum G-17, PGI, and (or) PGII may predict gastrointestinal bleeding risk among peptic ulcer patients.

AIM

To evaluate the efficacies of serum G-17, PGI, PGII, and PGI/PGII ratio (PGR) for predicting upper gastrointestinal bleeding among peptic ulcer patients.

METHODS

A total of 199 patients diagnosed with peptic ulcer confirmed by gastroscopy and positivity for Helicobacter pylori by the ¹⁴C-urea breath test were recruited, including 107 patients with simple peptic ulcer and 92 cases complicated by upper gastrointestinal bleeding. Serum PGI, PGII, G-17, and PGR were measured by immune methods and compared between bleeding and non-bleeding groups by univariate analysis. The specificity and sensitivity of PGs and G-17 for evaluating upper gastrointestinal bleeding risk were then assessed by constructing receiver operating characteristic (ROC) curves.

RESULTS

Serum G-17 was significantly higher among peptic ulcer patients with upper gastrointestinal bleeding compared to simple peptic ulcer patients (25.34 ± 14.29 vs 8.84 ± 8.03 pmol/L, t = 9.822, P < 0.01), whereas serum PGI, PGII, and PGR did not differ significantly between bleeding and non-bleeding groups (all P > 0.05). The risk of bleeding was significantly higher among peptic ulcer patients with elevated serum G-17 (> 15 pmol/L) compared to patients with normal or low serum G-17 (73.2% vs 27.4%, χ² = 40.72, P < 0.01). The area under the ROC curve for serum G-17 was 0.866 ± 0.024, and a cut-off of 9.86 pmol/L yielded 90.2% sensitivity and 68.2% specificity for distinguishing peptic ulcer with and without upper gastrointestinal bleeding.

CONCLUSION

Serum G-17 is significantly upregulated in peptic ulcer patients and higher levels are predictive of upper gastrointestinal bleeding. Conversely, serum PGI, PGII, and PGR have no predictive value. Further prospective studies are warranted to examine if high G-17 can be used to assess risk of bleeding prior to onset.

Prediction of Chronic Atrophic Gastritis and Gastric Neoplasms by Serum Pepsinogen Assay: A Systematic Review and Meta-Analysis of Diagnostic Test Accuracy

Serum pepsinogen assay (sPGA), which reveals serum pepsinogen (PG) I concentration and the PG I/PG II ratio, is a non-invasive test for predicting chronic atrophic gastritis (CAG) and gastric neoplasms. Although various cut-off values have been suggested, PG I ≤70 ng/mL and a PG I/PG II ratio of ≤3 have been proposed. However, previous meta-analyses reported insufficient systematic reviews and only pooled outcomes, which cannot determine the diagnostic validity of sPGA with a cut-off value of PG I ≤70 ng/mL and/or PG I/PG II ratio ≤3. We searched the core databases (MEDLINE, Cochrane Library, and Embase) from their inception to April 2018. Fourteen and 43 studies were identified and analyzed for the diagnostic performance in CAG and gastric neoplasms, respectively. Values for sensitivity, specificity, diagnostic odds ratio, and area under the curve with a cut-off value of PG I ≤70 ng/mL and PG I/PG II ratio ≤3 to diagnose CAG were 0.59, 0.89, 12, and 0.81, respectively and for diagnosis of gastric cancer (GC) these values were 0.59, 0.73, 4, and 0.7, respectively. Methodological quality and ethnicity of enrolled studies were found to be the reason for the heterogeneity in CAG diagnosis. Considering the high specificity, non-invasiveness, and easily interpretable characteristics, sPGA has potential for screening of CAG or GC.

Usefulness of OLGA and OLGIM system not only for intestinal type but also for diffuse type of gastric cancer, and no interaction among the gastric cancer risk factors

BACKGROUND

The operative link on gastric atrophy (OLGA) and operative link on gastric intestinal metaplasia (OLGIM) stages have been suggested for risk estimation of gastric cancer (GC). However, usefulness of OLGA/OLGIM systems in diffuse type of GC was not investigated so far. The aims of this study were to evaluate the OLGA/OLGIM systems in estimating the GC risk according to Lauren's classification and to investigate the interaction among the risk factors.

MATERIALS AND METHODS

The OLGA/OLGIM stages were evaluated in 1398 (765 control and 633 GC patients) who were prospectively enrolled in the Seoul National University Bundang Hospital. Synergistic interaction among the risk factors for GC was calculated using an additive model.

RESULTS

Among 387 intestinal-type GC patients, 71 (18.3%) were high-risk OLGA stages (III, IV) and 113 (29.2%) were high-risk OLGIM stages (III, IV). Of the 246 patients with diffuse-type GC, 36 (14.6%) were high-risk OLGA stages and 39 (15.9%) were high-risk OLGIM stages. Multivariable analysis revealed family history of GC, Helicobacter pylori infection, high-risk OLGA stages, and high-risk OLGIM stages as independent risk factors for GC regardless of histologic type (odds ratios [ORs] 1.78, 1.94, 2.63, and 3.18, respectively). There was no significant risk modification among the H. pylori infection, family history of GC, and high-risk OLGA/OLGIM stages.

CONCLUSION

High-risk OLGA/OLGIM stages are important prediction markers for GC regardless of H. pylori infection or family history of GC not only for the intestinal type but also for diffuse-type GC.

Method evaluation of pepsinogen I/II assay based on chemiluminescent immunoassays and comparison with other test methods

BACKGROUND

Serum pepsinogen (PG) I and the PG I/PG II ratio have been used for atrophic gastritis (AG) diagnosis for decades. Low levels of PG I and/or PG I/PG II are closely related to AG and predict the risk of gastric cancer. We evaluated the performance of the chemiluminescent immunoassay-based Architect Pepsinogen I/II assay.

METHODS

The evaluation consisted of determination of the precision, linearity, limit of blank (LoB), limit of detection (LoD) and method comparison with Eiken and Biohit assays.

RESULTS

The total CVs were below 5% for both PG I and PG II. Acceptable linearity was observed for PG I and PG II in their respective reportable ranges. The PG I LoB was 0.317ng/mL and the PG II LoB was 0.418ng/mL, and LoDs were 0.412ng/mL and 0.497ng/mL, respectively. Correlation analysis indicated that results of the Architect assay were comparable to those of the Eiken and Biohit assays, but the three methods lead to different estimations of the cancer risk.

CONCLUSION

The overall analytical performance of Architect Pepsinogen I/II assay is acceptable for the detection of patients with suspected AG. The categorization results of gastric cancer risk showed some difference among test methods suggesting the need for harmonization among the methods from vendors.

Helicobacter pylori: clinical management

PURPOSE OF REVIEW

Progress continues in our understanding of the role of Helicobacter pylori infection in gastroduodenal as well as extragastric disorders. This review gives an overview on selected areas of the H. pylori infection and their clinical implications.

RECENT FINDINGS

Indications for therapy have been extended and now include idiopathic thrombocytopenic purpura, iron deficiency anemia, and vitamin B12 deficiency. New data are presented on the role of H. pylori in neurodegenerative disorders and in the metabolic syndrome. H. pylori is associated with a (small) increase in the risk for colorectal adenoma and colon cancer. The biggest challenge is the selection of new therapies and treatment strategies because of the increasing failure of standard triple therapies. The best option in high clarithromycin resistance areas is bismuth-based quadruple therapy. Probiotic bacteria and yeasts reduce adverse effects of standard H. pylori eradication regimens. In gastric cancer prevention, screening programs based on the serological detection of preneoplastic conditions may prove useful.

SUMMARY

New algorithms for preventing H. pylori-induced disease and eradicating the organism should be individualized.

Serological assessment of gastric mucosal atrophy in gastric cancer

Background

Non-invasive tools for gastric cancer screening and diagnosis are lacking. Serological testing with the detection of pepsinogen 1 (PG1), pepsinogen 2 (PG2) and gastrin 17 (G17) offers the possibility to detect preneoplastic gastric mucosal conditions. Aim of this study was to assess the performance of these serological tests in the presence of gastric neoplasia.

Methods

Histological and serological samples of 118 patients with gastric cancer have been assessed for tumor specific characteristics (Laurén type, localisation), degree of mucosal abnormalities (intestinal metaplasia, atrophy) and serological parameters (PG1, PG2, PG1/2-ratio, G17, H. pylori IgG, CagA status). Association of the general factors to the different serological values have been statistically analyzed.

Results

Patients with intestinal type gastric cancer had lower PG1 levels and a lower PG1/2-ratio compared to those with diffuse type cancer (p = 0.003). The serum levels of PG2 itself and G17 were not significantly altered. H. pylori infection in general had no influence on the levels of PG1, PG2 and G17 in the serum of gastric cancer patients. There was a trend towards lower PG1 levels in case of positive CagA-status (p = 0.058). The degree of both intestinal metaplasia and atrophy correlated inversely with serum levels for PG1 and the PG1/2-ratio (p < 0.01). Laurén-specific analysis revealed that this is only true for intestinal type tumors. Univariate ANOVA revealed atrophy and CagA-status as the only independent factors for low PG1 and a low PG1/2-ratio.

Conclusions

Glandular atrophy and a positive CagA status are determinant factors for decreased pepsinogen 1 levels in the serum of patients with gastric cancer. The serological assessment of gastric atrophy by analysis of serum pepsinogen is only adequate for patients with intestinal type cancer.

Low serum pepsinogen I and pepsinogen I/II ratio and Helicobacter pylori infection are associated with increased risk of gastric cancer: 14-year follow up result in a rural Chinese community

The correlation between low serum PG level and H. pylori infection with the development of gastric cancer has caused considerable concerns all over the world. Some authors exclaimed that gastric cancer developed only in patients infected with H. pylori, whereas the other had different findings. In this study, 1,501 adult local residents with determined serum PG levels and anti H. pylori IgG status were followed for 14 years for the development of gastric cancer in a rural community with high risk of gastric cancer in Hebei Province, China. The results showed the accumulated gastric cancer incidence in the subjects with abnormal PG level and those with H. pylori infection were all significantly higher than that in the corresponding normal controls (53.9‰ vs. 12.7‰, p < 0.05 and 23.1‰ vs. 5.93‰, p < 0.05). The highest gastric cancer incidence was seen in the subjects with both abnormal serum PG and positive H. pylori (56.0‰), and followed by the subjects with abnormal PG and negative H. pylori (47.6‰) and those with normal serum PG and positive H. pylori (18.4‰). The abnormal serum PG level (OR 3.029) and H. pylori infection (OR 4.345) were all risk factors for the development of gastric cancer. The results suggested that the subjects with abnormal serum PG level and/or positive H. pylori infection in the rural area of China were all high risk population for gastric carcinoma and the subjects with both abnormal serum PG and positive H. pylori infection were at especially high risk for the development of gastric carcinoma.