Usefulness of serum pepsinogen levels as a screening test for atrophic gastritis and gastric cancer

Update on Serum Biomarkers in Autoimmune Atrophic Gastritis

BACKGROUND

Autoimmune atrophic gastritis (AAG) is a persistent, corpus-restricted immune-mediated destruction of the gastric corpus oxyntic mucosa with reduced gastric acid and intrinsic factor secretion, leading to iron deficiency and pernicious anemia as a consequence of iron and cobalamin malabsorption. Positivity toward parietal cell (PCA) and intrinsic factor (IFA) autoantibodies is very common. AAG may remain asymptomatic for many years, thus making its diagnosis complex and often delayed. Due to the increased risk of gastric neoplasms, a timely diagnosis of AAG is clinically important.

CONTENT

The gold standard for AAG diagnosis is histopathological assessment of gastric biopsies obtained during gastroscopy, but noninvasive, preendoscopic serological screening may be useful in some clinical scenarios. Serum biomarkers for AAG may be divided into 2 groups: gastric autoimmunity-related biomarkers, such as PCA and IFA, and gastric corpus atrophy/reduced gastric acid secretion-related biomarkers, such as serum gastrin and pepsinogens. The present review focuses on the clinical significance and pitfalls of serum biomarkers related to gastric autoimmunity and gastric corpus atrophy, including some discussion of analytical methods.

SUMMARY

Serum assays for PCA, IFA, gastrin, and pepsinogen I show good diagnostic accuracy for noninvasive diagnostic work-up of AAG. Diagnostic performance may increase by combining >1 of these tests, overcoming the problem of seronegative AAG. However, appropriately designed, comparative studies with well-characterized patient cohorts are needed to better define the reliability of these biomarkers in the diagnosis of patients with AAG. Currently, positive serum tests should always be followed by the state-of-art diagnostic test, that is, histopathological assessment of gastric biopsies obtained during gastroscopy to definitively confirm or rule out AAG and eventually neoplastic complications.

Targeted metabolomic profiles of serum amino acids and acylcarnitines related to gastric cancer

Background

Early diagnosis and treatment are imperative for improving survival in gastric cancer (GC). This work aimed to assess the ability of human serum amino acid and acylcarnitine profiles in distinguishing GC cases from atrophic gastritis (AG) and control superficial gastritis (SG) patients.

Methods

Sixty-nine GC, seventy-four AG and seventy-two SG control patients treated from May 2018 to May 2019 in Gansu Provincial Hospitalwere included. The levels of 42 serum metabolites in the GC, AG and SG groups were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, orthogonal partial least squares discriminant analysis (OPLS-DA) and the Kruskal-Wallis H test were used to identify a metabolomic signature among the three groups. Metabolites with highest significance were examined for further validation. Receiver operating characteristic (ROC) curve analysis was carried out for evaluating diagnostic utility.

Results

The metabolomic analysis found adipylcarnitine (C6DC), 3-hydroxy-hexadecanoylcarnitine (C16OH), hexanoylcarnitine (C6), free carnitine (C0) and arginine (ARG) were differentially expressed (all VIP >1) and could distinguish GC patients from AG and SG cases. In comparison with the AG and SG groups, GC cases had significantly higher C6DC, C16OH, C6, C0 and ARG amounts. Jointly quantitating these five metabolites had specificity and sensitivity in GC diagnosis of 98.55% and 99.32%, respectively, with an area under the ROC curve (AUC) of 0.9977.

Conclusion

This study indicates C6DC, C16OH, C6, C0 and ARG could effectively differentiate GC cases from AG and SG patients, and may jointly serve as a valuable circulating multi-marker panel for GC detection.

Atrophic gastritis is inversely associated with gastroesophageal reflux disease in a twin register based study

Background

The association between atrophic gastritis (AG) and symptomatic gastroesophageal reflux disease (GERD) needs to be better assessed.

Objective

We aimed to study this association in a twin setting, controlling for genetic and familial factors, in addition to a range of known covariates.

Methods

We performed a co‐twin control study based on the Swedish Twin Registry, including confirmed monozygotic (MZ) and dizygotic (DZ) twins. AG was determined by the measurement of serum pepsinogen I (PGI) and pepsinogen II (PGII), with different cut‐off values. GERD was defined using a structured questionnaire, by questions on symptoms of heartburn, acid regurgitation, pain behind the breastbone, and drug history. Patients were grouped into total GERD, less frequent (<1/week), and frequent GERD (≥1/week).

Results

A total of 12,533 twins were included in the study, among whom 37.7% showed less frequent GERD, and 18.7% had frequent GERD. There was an inverse association between AG and GERD, especially for frequent GERD. When PGI<30 was used as cut‐off value for AG, the odds ratio (OR) and corresponding 95% confidence interval (CI) was 0.52 (0.44, 0.62). When PGI<70 and PGI/PGII<3 was used as cut‐off value for AG, the OR (95% CI) was 0.53 (0.46, 0.63). A risk reduction for GERD was also observed in AG patients when the analysis was restricted in MZ or DZ twins.

Conclusion

In this co‐twin control study from the Swedish Twin Register, AG is persistently associated with a reduced risk for GERD, after controlling for genetic and shared familial factors.

Serum pepsinogen: A potential non-invasive screening method for moderate and severe atrophic gastritis among an asian population

Background

Serum pepsinogen has been approved and used widely as an effective biomarker in diagnosis of atrophic gastritis and gastric cancer; however, its validity and appropriate cut-off values vary among different populations. This study aimed to initially assess the diagnostic value of the serum pepsinogen in diagnosis of moderate and severe atrophic gastritis for Vietnamese population.

Materials and methods

A cross-sectional study enrolled 273 participants from June 2008 to November 2019. All participants underwent a gastroscopy procedure and three tests including serum PG test, pathology test, and Hp-Igg Elisa test. The Kimura-Takemoto classification and OLGA system were used to classify the mild versus moderate-severe atrophic gastritis. Receiver Operating Characteristic curve was used to assess the value of PGI, PGII and PGR.

Results

Based on Kimura-Takemoto classification, the AUC of PGI and PGR was 0.635 (p = 0.008, 95% CI 0.554–0.716) and 0.766 (p < 0.001, 95% CI 0.676–0.857) respectively. The best cut-off values were PGI ≤69.0 and PGR ≤4.6 (sensitivity: 73%, specificity: 83.9%, positive predictive value: 41.5%, negative predictive value: 95.2%, accuracy: 82.4%). According to the OLGA system, the AUC of PGI and PGR was 0.612 (p = 0.004, 95% CI 0.540–0.684) and 0.689 (p < 0.001, 95% CI 0.621–0.758) respectively. The best cut-off values were PGI ≤63.5 and PGR ≤5.2 (sensitivity: 49.4%, specificity: 82.1%, positive predictive value: 52.1%, negative predictive value: 80.5%, accuracy: 72.9%).

Conclusions

The serum pepsinogen II and pepsinogen I/II ratio had reliable diagnostic value for screening of moderate and severe atrophic gastritis among Vietnamese population. Further research was recommended to focus on larger scale to improve the diagnostic yield and to continue finding the cut-off values for diagnosis of gastric cancer among Vietnamese population.

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The validity and appropriate cut-off values of serum pepsinogen vary among different populations.

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In Vietnamese population, based on Kimura-Takemoto classification, the best cut-off values were PGI ≤69.0 and PGR ≤4.6.

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According to the OLGA system, the best cut-off values were PGI ≤63.5 and PGR ≤5.2.

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The serum pepsinogen II and pepsinogen I/II ratio had reliable diagnostic value for screening of moderate and severe atrophic gastritis among Vietnamese population.

Diagnostic Value of Serum Pepsinogen Levels for Screening Gastric Cancer and Atrophic Gastritis in Asymptomatic Individuals: A Cross-Sectional Study

Background

Pepsinogens (PGs) can be used for gastric cancer (GC) screening, but the cutoff levels vary among studies, and PG levels are influenced by numerous factors. The aim of this article is to examine the diagnostic value of PG levels and Helicobacter pylori (Hp) status for GC and atrophic gastritis screening in asymptomatic individuals undergoing health checkup in China.

Patients and Methods

This was a multicenter cross-sectional study of subjects who underwent health checkup from 10/2016 to 10/2018 at nine International Healthcare Centers in China. All participants underwent gastroscopy and pathological examination, serum PG, ¹³C-urea breath test, and/or Hp serological current infection marker rapid test, all on the same day. PG-related parameters were analyzed in different Hp subgroups and regions.

Results

The patients were grouped as non-atrophic (NAG, n = 1,590), mild to moderate atrophic (MAG, n = 273), severe atrophic (SAG, n = 49), and GC (n = 10). The serum PG levels in these groups decreased with increasing pathological severity. In the same pathological groups, PGI and PGII levels were higher in the Hp-positive subgroup, while PGR (PGI/PGII ratio) was lower (P < 0.05). The best cutoff values for atrophy diagnosis were PGI ≤73.1 ng/ml and PGR ≤9.8, for severe atrophy were PGI ≤63.9 ng/ml and PGR ≤9.09, and for GC was PGR ≤4.7 (all P < 0.05 and area under the curve >0.7). The cutoff points varied with Hp status and China regions.

Conclusion

Serum PG levels might be used for the screening of gastric atrophic gastritis lesions. The results suggest that different cutoff values should possibly be used in different Hp status groups and geographical regions, but it will have to be validated in future studies. Future studies should also examine the value of PG levels for GC detection.

Gastric cancer detection using the serum pepsinogen test method

BACKGROUND

Gastric cancer (GC) is the eighth most common cause of cancer deaths in Croatia and one of the most common causes of cancer deaths worldwide. A reliable diagnostic tool for the early detection of GC is essential.

OBJECTIVE

We previously suggested a pepsinogen test method to reduce the mortality from GC by allowing early detection. Here, we report an updated analysis from a prospective single-center clinical study to evaluate the sensitivity and specificity of the pepsinogen test method and to determine whether this test can be used as a part of routine laboratory assessment of high-risk patients.

METHODS

We present mature data of the pepsinogen test method in the Croatian population after a median follow-up of 36 months. Statistical analyses were performed using a Mann-Whitney U test, multiple logistic regression, and receiver operating characteristics (ROC) to evaluate the predictive power of the assayed biomarkers.

RESULTS

Of the 116 patients, 25 patients had GC and 91 demonstrated a nonmalignant pathology based on tissue biopsy. Cutoff values were pepsinogen I ⩽70 and pepsinogen I/II ratio ⩽3.0. Using ROC curve analysis, the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were determined to be 87.22%, 78.12%, 90.10%, 71.43%, and 92.86%, respectively, for the diagnosis of GC. The area under the curve was 0.700 (95% confidence interval 0.57-0.83).

CONCLUSION

Pepsinogen tests are valuable for screening a population in need of further diagnosis and could help to avoid unnecessary invasive endoscopic procedures.

Polymorphisms in Pepsinogen C and miRNA Genes Associate with High Serum Pepsinogen II in Gastric Cancer Patients

Background: Pepsinogen (PG) II (PGII) is a serological marker used to estimate the risk of gastric cancer but how PGII expression is regulated is largely unknown. It has been suggested that PGII expression, from the PGC (Progastricsin) gene, is regulated by microRNAs (miRNA), but how PGII levels vary with Helicobacter pylori (H. pylori) infection and miRNAs genotype remains unclear. Methods: Serum levels of PGI and PGII were determined in 80 patients with gastric cancer and persons at risk for gastric cancer (74 first-degree relatives of patients, 62 patients with autoimmune chronic atrophic gastritis, and 2 patients with dysplasia), with and without H. pylori infection. As control from the general population, 52 blood donors were added to the analyses. Associations between PGII levels and genetic variants in PGC and miRNA genes in these groups were explored based on H. pylori seropositivity and the risk for gastric cancer. The two-dimensional difference in gel electrophoresis (2D-DIGE) and the NanoString analysis of messenger RNA (mRNAs) from gastric cancer tissue were used to determine the pathways associated with increased PGII levels. Results: PGII levels were significantly higher in patients with gastric cancer, and in those with H. pylori infection, than in other patients or controls. A PGI/PGII ratio ≤ 3 was found better than PGI < 25 ng/mL to identify patients with gastric cancer (15.0% vs. 8.8%). For two genetic variants, namely rs8111742 in miR-Let-7e and rs121224 in miR-365b, there were significant differences in PGII levels between genotype groups among patients with gastric cancer (p = 0.02 and p = 0.01, respectively), but not among other study subjects. Moreover, a strict relation between rs9471643 C-allele with H. pylori infection and gastric cancer was underlined. Fold change in gene expression of mRNA isolated from gastric cancer tissue correlated well with polymorphism, H. pylori infection, increased PGII level, and pathway for bacteria cell entry into the host. Conclusions: Serum PGII levels depend in part on an interaction between H. pylori and host miRNA genotypes, which may interfere with the cut-off of PGI/PGII ratio used to identify persons at risk of gastric cancer. Results reported new findings regarding the relation among H. pylori, PGII-related host polymorphism, and genes involved in this interaction in the gastric cancer setting.

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.

Cost-effectiveness of combined serum anti-Helicobacter pylori IgG antibody and serum pepsinogen concentrations for screening for gastric cancer risk in Japan

BACKGROUND

A combination of assays for the presence of serum anti-Helicobacter pylori IgG antibody (HPA) and serum pepsinogen (PG) concentrations can be used to screen for gastric cancer risk. In Japan, this "ABC method" is considered an effective means of stratifying gastric cancer risk. This study aimed to ascertain its cost-effectiveness for assessing gastric cancer risk.

METHODS

A Markov model was constructed to compare the cost-effectiveness of two strategies for gastric cancer-risk screening over a 30-year period: the ABC method, which uses a combination of assessing the presence of HPA and measuring serum PG concentrations and scheduling endoscopies accordingly, and annual endoscopic screening. Clinical and epidemiological data on variables in the model were obtained from published reports. Analyses were made from the perspective of the Japanese health care payer.

RESULTS

According to base-case analysis, the ABC method cost less than annual endoscopic screening (64,489 vs. 64,074 USD) and saved more lives (18.16 vs. 18.30 quality-adjusted life years). One-way analyses confirmed the robustness of the cost-effectiveness results. The probability that the ABC method is cost-effective in Japanese individuals aged 50 years was 0.997.

CONCLUSIONS

A combination of HPA and serum PG assays, plus scheduling endoscopy accordingly, is a cost-effective method of screening for gastric cancer risk in Japan.

Significance of Serum Pepsinogens as a Biomarker for Gastric Cancer and Atrophic Gastritis Screening: A Systematic Review and Meta-Analysis

BACKGROUND

Human pepsinogens are considered promising serological biomarkers for the screening of atrophic gastritis (AG) and gastric cancer (GC). However, there has been controversy in the literature with respect to the validity of serum pepsinogen (SPG) for the detection of GC and AG. Consequently, we conducted a systematic review and meta-analysis to assess the diagnostic accuracy of SPG in GC and AG detection.

METHODS

We searched PubMed, Embase, and the Chinese National Knowledge Infrastructure (CNKI) for correlative original studies published up to September 30, 2014. The summary sensitivity, specificity, positive diagnostic likelihood ratio (DLR+), negative diagnostic likelihood ratio (DLR-), area under the summary receiver operating characteristic curve (AUC) and diagnostic odds ratio (DOR) were used to evaluate SPG in GC and AG screening based on bivariate random effects models. The inter-study heterogeneity was evaluated by the I2 statistics and publication bias was assessed using Begg and Mazumdar's test. Meta-regression and subgroup analyses were performed to explore study heterogeneity.

RESULTS

In total, 31 studies involving 1,520 GC patients and 2,265 AG patients were included in the meta-analysis. The summary sensitivity, specificity, DLR+, DLR-, AUC and DOR for GC screening using SPG were 0.69 (95% CI: 0.60-0.76), 0.73 (95% CI: 0.62-0.82), 2.57 (95% CI: 1.82-3.62), and 0.43 (95% CI: 0.34-0.54), 0.76 (95% CI: 0.72-0.80) and 6.01 (95% CI: 3.69-9.79), respectively. For AG screening, the summary sensitivity, specificity, DLR+, DLR-, AUC and DOR were 0.69 (95% CI: 0.55-0.80), 0.88 (95% CI: 0.77-0.94), 5.80 (95% CI: 3.06-10.99), and 0.35 (95% CI: 0.24-0.51), 0.85 (95% CI: 0.82-0.88) and 16.50 (95% CI: 8.18-33.28), respectively. In subgroup analysis, the use of combination of concentration of PGI and the ratio of PGI:PGII as measurement of SPG for GC screening yielded sensitivity of 0.70 (95% CI: 0.66-0.75), specificity of 0.79 (95% CI: 0.79-0.80), DOR of 6.92 (95% CI: 4.36-11.00), and AUC of 0.78 (95% CI: 0.72-0.81), while the use of concentration of PGI yielded sensitivity of 0.55 (95% CI: 0.51-0.60), specificity of 0.79 (95% CI: 0.76-0.82), DOR of 6.88 (95% CI: 2.30-20.60), and AUC of 0.77 (95% CI: 0.73-0.92). For AG screening, the use of ratio of PGI:PGII as measurement of SPG yielded sensitivity of 0.69 (95% CI: 0.52-0.83), specificity of 0.84 (95% CI: 0.68-0.93), DOR of 11.51 (95% CI: 6.14-21.56), and AUC of 0.83 (95% CI: 0.80-0.86), the use of combination of concentration of PGI and the ratio of PGI:PGII yield sensitivity of 0.79 (95% CI: 0.72-0.85), specificity of 0.89 (95% CI: 0.85-0.93), DOR of 24.64 (95% CI: 6.95-87.37), and AUC of 0.87 (95% CI: 0.81-0.92), concurrently, the use of concentration of PGI yield sensitivity of 0.46 (95% CI: 0.38-0.54), specificity of 0.93 (95% CI: 0.91-0.95), DOR of 19.86 (95% CI: 0.86-456.91), and AUC of 0.86 (95% CI: 0.52-1.00).

CONCLUSION

SPG has great potential as a noninvasive, population-based screening tool in GC and AG screening. In addition, given the potential publication bias and high heterogeneity of the included studies, further high quality studies are required in the future.