The serum pepsinogen levels for risk assessment of gastric neoplasms: New proposal from a case-control study in Korea

Useful Serum Pepsinogen Levels for Detecting Ongoing Helicobacter pylori Infection in Asymptomatic Subjects: A Cross-Sectional Study Based on 13C-urea Breath Test Findings

BACKGROUND /AIMS

The serum pepsinogen (PG) assay is used to screen subjects at high risk for gastric cancer. Currently, there are few studies on the PG levels for the detection of Helicobacter pylori infection. This study aimed to determine the PG assay findings for detecting ongoing infection.

METHODS

Asymptomatic subjects who underwent a ¹³C-urea breath test (¹³C-UBT) on the day of gastroscopy and serum assay for cancer screening were included. Subjects with a recent intake of acid suppressants or antibiotics, gastrectomy, or renal failure were excluded. H. pylori infection was defined as a positive ¹³C-UBT result.

RESULTS

Among the 500 included subjects, 167 (33.4%) had current infection. The serum PG II levels of > 12.95 ng/mL (area under the curve [AUC] = 0.930, sensitivity 86.5%, specificity 90.7%) and PG I/II ratios of < 4.35 (AUC = 0.875, sensitivity 86.8%, specificity 79.6%) were related to infection. The PG I/II ratios were inversely correlated with age (r = -0.160, p = 0.039). The cutoff values of PG I/II ratios were lower in older subjects aged ≥ 50 years (< 4.05; AUC = 0.875, sensitivity 80.7%, specificity 88.2%) than in younger subjects aged < 50 years (< 4.35; AUC = 0.873, sensitivity 77.4%, specificity 88.9%).

CONCLUSIONS

Serum PG II levels > 12.95 ng/mL and PG I/II ratios < 4.35 suggest ongoing infection in asymptomatic subjects; therefore, H. pylori confirmation tests (i.e., ¹³C-UBT) should be considered under these conditions. Stricter criteria are required in older subjects aged ≥ 50 years (PG I/II ratio < 4.05) to detect ongoing infection than younger subjects.

Prognosis of Seronegative Subjects with a Helicobacter pylori-infected Spouse

Background/Aims: Helicobacter pylori (H. pylori) can disseminate between couples. The present study compared the findings of gastric cancer screening between seronegative subjects according to the presence of an infected spouse.Materials and Methods: Follow-up data of seronegative subjects were analyzed among married couples who underwent gastric cancer screening via gastroscopy, serum pepsinogen, and anti-H. pylori IgG assays between January 2010 and May 2016. New detection rates of H. pylori infection and gastric neoplasm at the follow-up screening were compared between seronegative subjects according to the H. pylori-infected status of spouse.Results: Among 246 seronegative subjects with an H. pylori-infected spouse, 92 underwent follow-up tests (case group). Among 278 seronegative subjects with seronegative spouse, 94 underwent follow-up tests (control group). The past infection rate was higher in the case group than in the control group (52/92 vs. 34/94; P=0.005). New H. pylori infection was diagnosed in three of the 92 cases and two of the 94 controls (3.2% vs. 2.1%; P=0.681). During the mean follow-up of 67.9±36.0 months, three adenocarcinomas and two adenomas (5/184) were newly detected among the cases and their spouses, whereas none (0/188) were detected among the controls and their spouses (2.7% vs. 0%; P=0.029).Conclusions: Gastric neoplasm occurred more frequently in couples with an H. pylori-infected spouse. Because the past infection rate is higher among seronegative subjects with an infected spouse, gastric cancer screening is recommended in both partners when the spouse is infected.

Serum Assay Findings after Successful Helicobacter pylori Eradication

Serum pepsinogen (PG), anti-Helicobacter pylori (H. pylori) immunoglobulin G (IgG), and gastrin-17 (G-17) are plasma biomarkers for gastritis. H. pylori serology titers and PG levels increase during active H. pylori infection; moreover, elevated PG II levels indicate a high risk for diffuse-type gastric cancer in East Asian populations. Serum PG I/II ratios and PG I levels decrease with the progression of gastric corpus atrophy; thus, a combination of serum PG I levels ≤70 ng/mL and a PG I/II ratio ≤3 (serologic atrophy) indicates a high risk of intestinal-type gastric cancer. Serum G-17 is often not used as an indicator in H. pylori-seroprevalent populations because it is usually elevated in subjects with H. pylori infections. When H. pylori is eradicated, most patients show a rapid decrease in serum PG II levels and anti-H. pylori IgG titers within a few months. Seroreversion is required for several months to years after regression of H. pylori. Moreover, seroreversion may not always be achieved in all eradicated cases. The serum PG I/II ratio starts to increase after eradication; therefore, serologic atrophy improves accordingly, unless severe atrophy is present. Thus, some eradicated patients may show normal serum assay findings but have a higher risk for developing gastric cancer than H. pylori-naive subjects. Furthermore, serum PG levels decrease after gastrectomy and increase with the intake of certain drugs (e.g., aspirin or acid suppressants) or in renal failure patients. Due to such wide variations, serum assays are inadequate for the confirmation of H. pylori eradication. It is useful when interpreted with gastroscopy and other H. pylori test findings.

Scoring model for discriminating gastric cancer risk in patients with negative serum pepsinogen and anti-Helicobacter pylori antibody results

BACKGROUND

The ABC test measures serum pepsinogen and anti-Helicobacter pylori IgG antibody levels to predict precancerous conditions in the stomach and gastric cancer. However, a limitation of this test is that the gastric cancer risk is not negligible in patients with a negative result.

METHODS

Based on their ABC results, 1157 patients were classified into Groups A (n = 392), B (n = 479), C (n = 247), and D (n = 39). In Group A, 24.2% of patients had atrophic gastritis and/or intestinal metaplasia and had thus been incorrectly assigned to Group A. Patients in Group A were then assigned to derivation (n = 236) and validation (n = 156) cohorts by 3:2 random sampling. Logistic regression analyses were performed to identify the factors discriminating between a correct (true) and incorrect (false) Group A classification.

RESULTS

A 4-point discriminative model was constructed based on a high-negative H. pylori IgG antibody titer and the patient's age (50-64 and ≥65 years). The areas under the receiver operating characteristic curve for the derivation and validation cohorts were 0.868 and 0.894, respectively. In the validation cohort, the addition of a discriminative model score ≥2 to the ABC method showed a similar accuracy for predicting gastric cancer risk compared with the ABC method alone (93.8% vs. 92.4%).

CONCLUSION

The 4-point discriminative model may help identify patients with a normal serological test who are nonetheless at risk of developing gastric cancer.

Clinical Value of Combined Detection of Serum sTim-3 and Pepsinogen for Gastric Cancer Diagnosis

Purpose

The present study aimed to evaluate the clinical value of the combined detection of soluble T cell immunoglobulinand mucin domain molecule 3 (sTim-3) and pepsinogen (PG) in sera for gastric cancer (GC) diagnosis.

Patients and Methods

The double antibody sandwich method was used to establish a highly sensitive time-resolved fluorescence immunoassay for the detection of sTim-3. Serum sTim-3, PGI, and PGII levels in 149 GC patients (123 first-diagnosis GC patients and 26 post-GC patients), 81 patients with benign gastric disease (BGD), and 73 healthy controls were quantitatively detected. The clinical diagnostic value of the combined detection of sTim-3 and PG in GC was analyzed.

Results

Serum sTim-3 levels in GC (20.41 ± 9.55 ng/mL) and BGD (16.50 ± 9.76 ng/mL) patients were significantly higher (P < 0.001) than those in healthy controls (9.22 ± 3.40 ng/mL). Combined detection of sTim-3 and PGI/PGII (AUC: 0.9330, sensitivity: 86.44%, and specificity: 91.78%) showed a high diagnostic value for GC. When the level of PGI/PGII was less than 12.11 and that of sTim-3 was greater than 14.30 ng/mL, the positive rate of the control group was reduced to 0%, and the positive detection rate of GC was 54.47%. In addition, in post-operative patients, serum sTim-3 levels in the recurrence group (33.56 ± 4.91 ng/mL) were significantly higher than those in the no recurrence group (11.95 ± 5.16 ng/mL).

Conclusion

sTim-3 levels in BGD and GC sera were significantly higher than those in the control group sera. Additionally, sTim-3 serum levels can predict recurrence in post-operative patients. Compared with PG alone, the combined detection of serum PG and sTim-3 can significantly improve the detection sensitivity and specificity of BGD and GC.

Using machine-learning algorithms to identify patients at high risk of upper gastrointestinal lesions for endoscopy

BACKGROUND AND AIM

Endoscopic screening for early detection of upper gastrointestinal (UGI) lesions is important. However, population-based endoscopic screening is difficult to implement in populous countries. By identifying high-risk individuals from the general population, the screening targets can be narrowed to individuals who are in most need of an endoscopy. This study was designed to develop an artificial intelligence (AI)-based model to predict patient risk of UGI lesions to identify high-risk individuals for endoscopy.

METHODS

A total of 620 patients (from 5300 participants) were equally allocated into 10 parts for 10-fold cross validation experiments. The machine-learning predictive models for UGI lesion risk were constructed using random forest, logistic regression, decision tree, and support vector machine (SVM) algorithms. A total of 48 variables covering lifestyles, social-economic status, clinical symptoms, serological results, and pathological data were used in the model construction.

RESULTS

The accuracies of the four models were between 79.3% and 93.4% in the training set and between 77.2% and 91.2% in the testing dataset (logistics regression: 77.2%; decision tree: 87.3%; random forest: 88.2%; SVM: 91.2%;). The AUCs of four models showed impressive predictive ability. Comparing the four models with the different algorithms, the SVM model featured the best sensitivity and specificity in all datasets tested.

CONCLUSIONS

Machine-learning algorithms can accurately and reliably predict the risk of UGI lesions based on readily available parameters. The predictive models have the potential to be used clinically for identifying patients with high risk of UGI lesions and stratifying patients for necessary endoscopic screening.

Current and potential biomarkers in gastric cancer: a critical review of the literature

Gastric cancer is the fourth most common type of cancer worldwide and the second most lethal. Gastric cancer biomarkers can be used for diagnosis, prediction of sensitivity to treatment, and prognosis. The following search terms were applied to PubMed as of December 2020: 'gastric cancer classification', 'gastric cancer epidemiology', 'cancer metastasis' and 'gastric cancer biomarker'. Only experimental studies were reported in the 'biomarkers' section. Some biomarkers can serve as therapeutic targets for antitumoral drugs. The genes analyzed include E-cadherin, RPRM, XAF1, MINT25, TFF1, p16 and p53. The miRNAs analyzed include miR-18a, miR185-5p, miR-125b and miR-21. Some molecules were associated with metastasis of gastric cancer, specifically those involved with EMT process and tissue degradation.

Standard vs magnifying narrow-band imaging endoscopy for diagnosis of Helicobacter pylori infection and gastric precancerous conditions

BACKGROUND

Advances in endoscopic imaging enable the identification of patients at high risk of gastric cancer. However, there are no comparative data on the utility of standard and magnifying narrow-band imaging (M-NBI) endoscopy for diagnosing Helicobacter pylori (H. pylori) infection, gastric atrophy, and intestinal metaplasia.

AIM

To compare the diagnostic performance of standard and M-NBI endoscopy for H. pylori gastritis and precancerous conditions.

METHODS

In 254 patients, standard endoscopy findings were classified into mosaic-like appearance (type A), diffuse homogenous redness (type B), and irregular redness with groove (type C). Gastric mucosal patterns visualized by M-NBI were classified as regular round pits with polygonal sulci (type Z-1), more dilated and linear pits without sulci (type Z-2), and loss of gastric pits with coiled vessels (type Z-3).

RESULTS

The diagnostic accuracy of standard and M-NBI endoscopy for H. pylori gastritis was 93.3% and 96.1%, respectively. Regarding gastric precancerous conditions, the accuracy of standard and M-NBI endoscopy was 72.0% vs 72.6% for moderate to severe atrophy, and 61.7% vs. 61.1% for intestinal metaplasia in the corpus, respectively. Compared to type A and Z-1, types B+C and Z-2+Z-3 were significantly associated with moderate to severe atrophy [odds ratio (OR) = 5.56 and 8.67] and serum pepsinogen I/II ratio of ≤ 3 (OR = 4.48 and 5.69).

CONCLUSION

Close observation of the gastric mucosa by standard and M-NBI endoscopy is useful for the diagnosis of H. pylori gastritis and precancerous conditions.

GASTROSCOPY WITH BIOPSY AND/OR SEROLOGICAL BIOPSY AS THE PRIMARY METHOD OF DIAGNOSIS OF GASTRIC MUCOSA CONDITION

Nowadays formal programs for screening of early cancer and precancerous conditions of the gastric mucosa exist only in Japan and South Korea, where studies of the upper gastrointestinal are carried out in people at the age of 40 and older.

Objective of the study: to assess the condition of the gastric mucosa in 40-50 year-old patients by means of determination of pepsinogen 1 and pepsinogen 2 concentration ratio, and esophagogastroduodenoscopy complemented by biopsy.

Materials and methods. The analysis included examination results of 23 patients with the diagnosis: "unspecified dyspepsia". Gender distribution of patients: women – 12, men – 11, average age 46 + 3.6 years (M + m). It was a single-stage study. All patients underwent video esophagogastroduodenoscopy. There were also taken two biopsy samples, from the antrum and the body of the stomach, for a rapid urease test, and then the patients underwent blood sampling. Inclusion criteria: patients with dyspeptic symptoms who have not been previously examined and have not received any treatment; aged 40 to 50 years; voluntary informed consent for examination, positive result of rapid urease test. Withdrawal criteria: refusal to participate in the study, duodenal ulcer.

Results. Atrophic gastritis was identified during endoscopic and morphological examination in three patients (out of 23) with gastric ulcers, but the concentration ratio of pepsinogen 1 and pepsinogen 2 was higher than 3/1.

Conclusion. Our study has shown that determination of concentration ratio of pepsinogen 1 and pepsinogen 2 in patients under 50 does not reflect the presence of atrophic changes in the mucous membrane.

Long-term follow up of serum pepsinogens in patients with gastric cancer or dysplasia after Helicobacter pylori eradication

BACKGROUND AND AIM

Few studies have evaluated the change in serum pepsinogen (sPG) levels after the eradication of Helicobacter pylori. The aim of this study was to evaluate the effect of H. pylori eradication on sPG levels in patients with gastric cancer/dysplasia in comparison to a control group.

METHODS

We prospectively enrolled 368 patients with gastric cancer/dysplasia and 610 control subjects. H. pylori status and sPG levels were measured before and after eradication. The follow-up time points were classified as < 12, 12-23, 24-35, and ≥ 36 months.

RESULTS

In 179 H. pylori-eradicated patients with gastric cancer/dysplasia and 168 control group subjects, sPG I significantly decreased, and the sPG I/II ratio significantly increased after eradication compared to baseline, and this improvement in sPG values was maintained during all follow-up time points. Significant differences in sPG I and the sPG I/II ratio were observed between the gastric cancer/dysplasia group and the control group < 24 months after eradication. However, these differences in sPG values disappeared after ≥ 24 months of follow up. Moreover, significant differences in the intestinal metaplasia grade were observed between these two groups before eradication until < 24 months after eradication. However, these differences in the intestinal metaplasia grade disappeared after ≥ 24 months of follow up in the corpus.

CONCLUSION

The sPG values and intestinal metaplasia grade (corpus) in the gastric cancer/dysplasia group became similar to those in the control group at long-term follow up after H. pylori eradication. It might be related with the reduction of metachronous gastric neoplasm.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Serum pepsinogens as a gastric cancer and gastritis biomarker in South and Southeast Asian populations

Serum pepsinogens have been widely acknowledged as gastric mucosal biomarkers; however, a multicountry report on the benefits of pepsinogens as biomarkers has not yet been published. We analyzed 1,206 sera and gastric mucosal samples collected from Bangladesh, Bhutan, Indonesia, Myanmar, Nepal and Thailand then assessed the association between gastric mucosal changes and Helicobacter pylori infection. The new cutoff values for serum pepsinogen values were evaluated using a receiver operating characteristic analysis. The participants with H. pylori infection had significantly lower pepsinogen I and higher pepsinogen II values, but a lower pepsinogen I/II ratio than participants without the infection (all P < .001). The pepsinogen I and pepsinogen I/II values were significantly higher and lower, respectively, in individuals with atrophic gastritis than in those without (both P < .001). Among uninfected individuals, only the pepsinogen I/II ratio was significantly lower in atrophic individuals. Pepsinogen I/II ratio also were significantly different between disease among H. pylori-positive and H. pylori-negative individuals, suggesting the pepsinogen I/II ratio is a robust biomarker for determining both chronic and atrophic gastritis. The cutoffs for detecting chronic and atrophic gastritis for the pepsinogen I/II ratio were 4.65 and 4.95, respectively. In conclusion, pepsinogen levels are useful biomarker for both chronic gastritis and atrophic gastritis, but they should be used with caution. Population-based validation is necessary to determine the best cutoff values. Among all pepsinogen values, the pepsinogen I/II ratio was the most reliable gastric mucosal-change biomarker.

Analysis of factors associated with recovery of the serum pepsinogen ratio after Helicobacter pylori eradication: a long-term follow-up study in Korea

Objective: Serum levels of pepsinogen (PG) are related to Helicobacter pylori-induced inflammation of the gastric mucosa. This study aimed to examine the influence of H. pylori eradication on serum PG, analyze its associated factors, and evaluate the long-term outcomes.Methods: H. pylori-positive patients who underwent gastroscopy and serum PG measurement were enrolled in a single academic hospital. After H. pylori eradication, the measurement of serum PG level was performed. Recovery of serum PG I/II ratio was defined as a PG I/II ratio after eradication of >3.0 in patients with a PG I/II ratio ≤ 3.0 before eradication. Follow-up involved serum PG measurement and gastroscopy with a rapid urease test annually.Results: In all, 327 patients were eligible for study inclusion. Compared to those before H. pylori eradication, serum PG I (74.9 vs. 44.3 ng/mL, p < .001) and PG II (25.4 vs. 9.1 ng/mL, p < .001) levels significantly decreased after successful eradication. In addition, there was a significant increase in serum PG I/II ratio after eradication (3.07 vs. 4.98, p < .001). In multivariate analyses, the following were independently associated with failed recovery of serum PG I/II ratio despite successful eradication: age ≥ 60 years (odds ratio [OR] = 0.231, 95% confidence interval [CI] = 0.084-0.629, p = .004) and severe gastric atrophy (OR = 0.156, 95% CI = 0.055-0.440, p < .001).Conclusions: Recovery of serum PG I/II ratio after H. pylori eradication may be achieved in H. pylori-infected patients aged <60 years without severe gastric atrophy.

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.

The Value of Pepsinogen in GC Screening: A Systematic Review and Meta-Analysis

Background

The current gold standard for gastric cancer (GC) screening is pathology or a barium meal followed by X-ray. This is not applicable to a wide range of screening capabilities due to the lack of operability. This article used a meta-analysis to evaluate the value of pepsinogen (PG) screening for GC.

Methods

PubMed, EMbase, the Cochrane Library, CNKI, WanFang, VIP, and CBM databases were systematically searched for published studies that used serum PG to diagnose GC. Articles were searched from January 2003 to January 2018. Two reviewers independently screened the literature according to specified inclusion and exclusion criteria. The data were extracted and evaluated, and the quality of the methodologies evaluated using the QUADAS entry. The meta-analysis (MA) was performed using Meta-DiSc 1.4 software. Stata 12.0 software was used to assess publication bias.

Results

A total of 19 studies were finally included from a total of 169,009 cases. The MA showed a combined sensitivity and specificity of 0.56 (95% CI (0.53-0.59), P < 0.01) and 0.71 (95% CI (0.70-0.71), P < 0.01), respectively. The combined likelihood ratios were +LR = 2.82 (95% CI (2.06-3.86), P < 0.01) and -LR = 0.56 (95% CI (0.45-0.68), P < 0.01). The combined DOR was 5.41 (95% CI (3.64~ 8.06), P < 0.01), and the area under the SROC curve was 0.7468.

Conclusions

Serum PG provides medium levels of sensitivity and specificity for GC assessment. To be used in a clinical setting, further high-quality research must be performed and verified.