Serum pepsinogen level, atrophic gastritis and the risk of incident pancreatic cancer--a prospective cohort study

The Role of Circulating Protein and Metabolite Biomarkers in the Development of Pancreatic Ductal Adenocarcinoma (PDAC): A Systematic Review and Meta-analysis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis, and this is attributed to it being diagnosed at an advanced stage. Understanding the pathways involved in initial development may improve early detection strategies. This systematic review assessed the association between circulating protein and metabolite biomarkers and PDAC development.

METHODS

A literature search until August 2020 in MEDLINE, EMBASE, and Web of Science was performed. Studies were included if they assessed circulating blood, urine, or salivary biomarkers and their association with PDAC risk. Quality was assessed using the Newcastle-Ottawa scale for cohort studies. Random-effects meta-analyses were used to calculate pooled relative risk.

RESULTS

A total of 65 studies were included. Higher levels of glucose were found to be positively associated with risk of developing PDAC [n = 4 studies; pooled relative risk (RR): 1.61; 95% CI: 1.16-2.22]. Additionally, an inverse association was seen with pyridoxal 5'-phosphate (PLP) levels (n = 4 studies; RR: 0.62; 95% CI: 0.44-0.87). Meta-analyses showed no association between levels of C-peptide, members of the insulin growth factor signaling pathway, C-reactive protein, adiponectin, 25-hydroxyvitamin D, and folate/homocysteine and PDAC risk. Four individual studies also reported a suggestive positive association of branched-chain amino acids with PDAC risk, but due to differences in measures reported, a meta-analysis could not be performed.

CONCLUSIONS

Our pooled analysis demonstrates that higher serum glucose levels and lower levels of PLP are associated with risk of PDAC.

IMPACT

Glucose and PLP levels are associated with PDAC risk. More prospective studies are required to identify biomarkers for early detection.

Gastric Mucosal Abnormality and Risk of Pancreatic Cancer: A Population-Based Gastric Biopsy Cohort Study in Sweden

BACKGROUND

It remains open whether gastric precancerous lesions are associated with an elevated risk of pancreatic cancer. Our aim was to investigate the association between gastric mucosal status and pancreatic cancer risk.

METHODS

Patients with gastric biopsies [normal, minor changes, superficial gastritis, and atrophic gastritis/intestinal metaplasia/dysplasia (AG/IM/Dys)] from the Swedish histopathology registers during 1979 to 2011 were included. Cross-linkages with several nationwide registries allowed complete follow-up and identification of pancreatic cancer cases until 2014. Standardized incidence ratios (SIR) and HRs were estimated.

RESULTS

During 3,438,248 person-years of follow-up with 318,653 participants, 3,540 cases of pancreatic cancer were identified. The same pattern of excess risk of pancreatic cancer compared with the general population was observed across all groups: a peak of 12- to 21-fold excess risk in the first year after biopsy [e.g., normal: SIR = 17.4; 95% confidence interval (CI), 15.7-19.3; AG/IM/Dys: SIR = 11.5; 95% CI, 9.9-13.4], which dropped dramatically during the second and third years, followed by 20% to 30% increased risk after the third year (e.g., normal: SIR = 1.2; 95% CI, 1.1-1.4; AG/IM/Dys: SIR = 1.3; 95% CI, 1.1-1.5). However, no significant excess risk was observed with the normal gastric mucosa as reference.

CONCLUSIONS

This unique, large pathologic cohort study did not find evidence that abnormal gastric mucosal status is causally associated with a long-term pancreatic cancer risk. However, a highly increased short-term risk was observed for people undergoing gastroscopy with biopsy sampling compared with the general population.

IMPACT

Further studies for a long-term risk of pancreatic cancer in patients with gastric biopsies are needed, with further adjustments.

Helicobacter pylori infection, atrophic gastritis, and risk of pancreatic cancer: A population-based cohort study in a large Japanese population: the JPHC Study

Helicobacter pylori (H. pylori), an established risk factor for gastric cancer, is suggested to also play a role in the development of pancreatic cancer; however, the association remains inconclusive. We examined this association among Japanese men and women. H. pylori and atrophic gastritis (AG) status were determined serologically, using blood sample collected during health checkups. A total of 20,116 subjects enrolled in the Japan Public Health Center-based Prospective Study Cohort II with available data on H. pylori seropositivity (anti-H. pylori) and AG were followed until the end of 2010. Cox proportional hazards models were used to calculate the hazard ratios (HR) and 95% confidence intervals (CI), using the information from the baseline survey. During 320,470 person-years of follow-up, 119 cases of pancreatic cancer were identified. No statically significant increase or decrease in pancreatic cancer risk was observed for H. pylori and AG status, independently or in combination. In a multivariable-adjusted model, we observed a non-significant decrease in the risk among those who had AG but were anti-H. pylori seronegative (HR 0.57, 95% CI 0.31–1.03). In a stratified analysis, we observed a statistically significant increased risk of pancreatic cancer for AG+ (HR 3.64, 95% CI 1.37–9.66), and AG+/anti-H. pylori− or AG+/anti-H. pylori+ (HR 5.21, 95% CI 1.14–23.87) among current smokers. Non-smokers in all categories of AG and anti-H. pylori showed a non-statistical decrease in the risk. There was no statistically significant interaction between H. pylori infection, AG status, and smoking status. Our findings suggest H. pylori seropositivity and AG, individually or in combination, are not associated with the risk of pancreatic cancer in a general Japanese population. Among current smokers, pancreatic cancer risk increased with AG, regardless of H. pylori infection status.

Helicobacter pylori infection, atrophic gastritis, and pancreatic cancer risk: A meta-analysis of prospective epidemiologic studies

BACKGROUND

To investigate the associations of Helicobacter pylori (Hp) infection and atrophic gastritis (AG) with pancreatic cancer risk.

METHODS

A literature search in PubMed was performed up to July 2017. Only prospective cohort and nested case-control studies enrolling cancer-free participants were eligible. Incident pancreatic cancer cases were ascertained during the follow-up. The risks of pancreatic cancer were compared between persons infected and noninfected with Hp, or between those with and without AG status at baseline. Odds ratios (ORs) or hazard ratios were combined. Subgroup and sensitivity analyses were performed, and publication bias was estimated.

RESULTS

Three cohort studies and 6 nested case-control studies, including 65,155 observations, were analyzed. The meta-analyses did not confirm the association between pancreatic cancer risk and Hp infection (OR = 1.09, 95% confidence interval [CI] = 0.81-1.47) or AG status (OR = 1.18, 95% CI = 0.80-1.72). However, particular subpopulations potentially had increased risks of pancreatic cancer. Cytotoxin-associated gene A (CagA)-negative strains of Hp might be a causative factor of pancreatic cancer (OR = 1.30, 95% CI = 1.05-1.62), but a sensitivity analysis by leave-one-out method did not fully warrant it (OR = 1.20, 95% CI = 0.93-1.56). In 1 nested case-control study, AG at stomach corpus in Hp-negative subpopulation might have increased risk of pancreatic cancer, but with a poor test power = 0.56. Publication biases were nonsignificant in the present meta-analysis.

CONCLUSION

Based on current prospective epidemiologic studies, the linkage of pancreatic cancer to Hp infection or AG status was not warranted on the whole. Nevertheless, prospective studies only focusing on those specific subpopulations are further required to obtain better power.

Helicobacter pylori infection, chronic corpus atrophic gastritis and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort: A nested case-control study

The association between H. pylori infection and pancreatic cancer risk remains controversial. We conducted a nested case-control study with 448 pancreatic cancer cases and their individually matched control subjects, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, to determine whether there was an altered pancreatic cancer risk associated with H. pylori infection and chronic corpus atrophic gastritis. Conditional logistic regression models were applied to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs), adjusted for matching factors and other potential confounders. Our results showed that pancreatic cancer risk was neither associated with H. pylori seropositivity (OR = 0.96; 95% CI: 0.70, 1.31) nor CagA seropositivity (OR = 1.07; 95% CI: 0.77, 1.48). We also did not find any excess risk among individuals seropositive for H. pylori but seronegative for CagA, compared with the group seronegative for both antibodies (OR = 0.94; 95% CI: 0.63, 1.38). However, we found that chronic corpus atrophic gastritis was non-significantly associated with an increased pancreatic cancer risk (OR = 1.35; 95% CI: 0.77, 2.37), and although based on small numbers, the excess risk was particularly marked among individuals seronegative for both H. pylori and CagA (OR = 5.66; 95% CI: 1.59, 20.19, p value for interaction < 0.01). Our findings provided evidence supporting the null association between H. pylori infection and pancreatic cancer risk in western European populations. However, the suggested association between chronic corpus atrophic gastritis and pancreatic cancer risk warrants independent verification in future studies, and, if confirmed, further studies on the underlying mechanisms.

Iron in relation to gastric cancer in the Alpha-tocopherol, Beta-carotene Cancer Prevention Study

BACKGROUND

Iron is an essential micronutrient that can have carcinogenic effects when at high or low concentrations. Previous studies of iron in relation to gastric cancer have not assessed subtype-specific relationships. We used the prospective Alpha-Tocopherol, Beta-Carotene (ATBC) Cancer Prevention Study to assess whether iron metrics were associated with gastric cardia cancer (GCC) and gastric noncardia cancer (GNCC).

METHODS

We selected 341 incident gastric cancer cases (86 cardia, 172 noncardia, and 83 nonspecified), accrued during 22 years of follow-up, and 341 individually matched controls. We measured prediagnostic serum iron, ferritin, unsaturated iron binding capacity, and C-reactive protein. Total iron-binding capacity (TIBC) and transferrin saturation were estimated from these metrics. Dietary iron exposures were estimated from a food frequency questionnaire. Multivariable logistic regression was used for analysis.

RESULTS

Serum iron metrics were not associated with GCC, except for a potential "n"-shaped relationship with TIBC (global P = 0.038). GNCC was inversely associated with serum ferritin (global P = 0.024), serum iron (global P = 0.060) and, possibly, transferrin saturation. TIBC appeared to share a "u"-shaped relationship with GNCC (global P = 0.033). Dietary iron exposures were not associated with either subsite. Adjustment for Helicobacter pylori and gastric atrophy had little effect on observed associations.

CONCLUSIONS

We found little evidence for the involvement of iron exposure in the pathogenesis of GCC. GNCC was associated with an iron profile similar to that of iron deficiency.

IMPACT

Our findings indicate that inverse associations between iron metrics and gastric cancer are driven by associations with GNCC. Further elucidation of potential mechanisms is warranted.

Pepsinogen I/II ratio is related to glucose, triacylglycerol, and uric acid levels

OBJECTIVE

Under- and overnutrition are associated with a worse prognosis and constitute independent risk factors for morbidity and mortality. It is increasingly important to understand the factors that affect nutritional and metabolic statuses. The purpose of this study was to assess the relation between the pepsinogen I/II ratio and several biochemical markers.

METHODS

A cross-sectional study was performed in 1985 subjects who underwent a health screening test. Subjects had no medications for hyperuricemia, dyslipidemia, diabetes mellitus, or hypertension. All subjects were classified into two groups. Subjects with a pepsinogen I/II ratio below 3 were defined as having atrophic gastritis. The relations between the pepsinogen I/II ratio and several biochemical markers, including total cholesterol, triacylglycerol, uric acid, cholinesterase, and glucose levels, were evaluated.

RESULTS

The presence of atrophic gastritis was significantly associated with age, smoking status, alcohol consumption, body mass index, and triacylglycerol, uric acid, cholinesterase, and hemoglobin levels. Multiple linear regression analysis demonstrated that the pepsinogen I/II ratio was an independent determinant of glucose level (β = 0.104, P < 0.0001), triacylglycerol level (β = 0.072, P = 0.0014), uric acid level (β = 0.048, P = 0.0138), and hemoglobin (β = 0.037, P = 0.0429) after adjustments for age, sex, smoking status, alcohol consumption, and body mass index.

CONCLUSION

The pepsinogen I/II ratio was related to glucose, triacylglycerol, and uric acid levels. Such an association fosters the idea that a decreased pepsinogen I/II ratio seems favorable for the prevention of overnutrition.

Pancreatic cancer biomarkers and their implication in cancer diagnosis and epidemiology

Pancreatic cancer is the fourth most common cause of cancer-related mortality in the United States. Biomarkers are needed to detect this cancer early during the disease development and for screening populations to identify those who are at risk. In cancer, “biomarker” refers to a substance or process that is indicative of the presence of cancer in the body. A biomarker might be either a molecule secreted by a tumor or it can be a specific response of the body to the presence of cancer. Genetic, epigenetic, proteomic, glycomic, and imaging biomarkers can be used for cancer diagnosis, prognosis, and epidemiology. A number of potential biomarkers have been identified for pancreatic cancer. These markers can be assayed in non-invasively collected biofluids. These biomarkers need analytical and clinical validation so that they can be used for the purpose of screening and diagnosing pancreatic cancer and determining disease prognosis. In this article, the latest developments in pancreatic cancer biomarkers are discussed.