Less than a century ago, gastric cancer was the most common cancer in the United States and perhaps throughout the world. Despite its worldwide decline in incidence over the past century, gastric cancer remains a major killer across the globe. This article reviews the epidemiology, screening, and prevention of gastric cancer. We first discuss the descriptive epidemiology of gastric cancer, including its incidence, survival, mortality, and trends over time. Next, we characterize the risk factors for gastric cancer, both environmental and genetic. Serologic markers and histological precursor lesions of gastric cancer and early detection of gastric cancer using these markers are reviewed. Finally, we discuss prevention strategies and provide suggestions for further research. Cancer Epidemiol Biomarkers Prev; 23(5); 700–13. ©2014 AACR.

Background: Methods: Results: Conclusion:

Background: Several studies have reported an association between gastric atrophy and upper gastrointestinal cancers. Our aim was to summarise the available information and calculate the relative risks (RRs) associated with gastric atrophy for gastric cardia adenocarcinoma (GCA), oesophageal squamous cell carcinoma (OSCC), and oesophageal adenocarcinoma (OAC) by conducting a systematic review and meta-analysis. Methods: We searched the PubMed and ISI-Web of Science databases, as well as the reference lists of the relevant articles. Summary RRs and 95% confidence intervals (95% CI) were calculated using random-effects models for the association between gastric atrophy, defined histologically or by serum pepsinogen markers, and OSCC, OAC, and GCA. Results: Eighteen articles were included in the meta-analysis; 13, 7, and 3 studies reported on GCA, OSCC, and OAC, respectively. The overall RRs (95% CI) for the three cancer types were: GCA, 2.89 (2.09–3.98); OSCC, 1.94 (1.48–2.55); OAC, 0.51 (0.19–1.37). Several subgroup analyses showed the robustness of the results. In the majority of the analyses, there was low to moderate heterogeneity. Conclusions: This study found two- to threefold increased risk of OSCC and GCA but a possible reduced risk of OAC in people with gastric atrophy. Further studies are needed to establish the association with OAC and causal association with OSCC, and mechanisms of the increased risk need to be investigated for GCA.

Ive cohort study in northeastern Iran, with detailed, validated data on opium use and several other exposures. A total of 50,045 adults were enrolled during a 4-year period (2004–2008) and followed annually until December 2012, with a follow-up success rate of 99%. We used Cox proportional hazard regression models to evaluate the association between opium use and outcomes of interest. RESULTS: In all, 8,487 (17%) participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 474 deaths from digestive diseases were reported (387 due to gastrointestinal cancers and 87 due to nonmalignant etiologies). Opium use was associated with an increased risk of death from any digestive disease (adjusted hazard ratio (HR)=1.55, 95% confidence interval (CI)=1.24–1.93). The association was dose dependent, with a HR of 2.21 (1.57–3.31) for the highest quintile of cumulative opium use vs. no use (Ptrend=0.037). The HRs (95% CI) for the associations between opium use and malignant and nonmalignant causes of digestive mortality were 1.38 (1.07–1.76) and 2.60 (1.57–4.31), respectively. Increased risks were seen both for smoking opium and for ingestion of opium. CONCLUSIONS: Long-term opium use, even in low doses, is associated with increased risk of death from both malignant and nonmalignant digestive diseases....

Background and Aims: Although several studies have suggested opium as a risk factor for cancers of the esophagus, stomach, larynx, lung, and bladder, no previous study has examined the association of opium with pancreatic cancer. We aimed to study the association between opium use and risk of pancreatic cancer in Iran, using a case-control design. We also studied the association of cigarette smoking and alcohol consumption with pancreatic cancer, for which little information was available from this population. Methods: Cases and controls were selected from patients who were referred to 4 endoscopic ultrasound centers in Tehran, Iran. We recruited 316 histopathologically (all adenocarcinoma) and 41 clinically diagnosed incident cases of pancreatic cancer, as well as 328 controls from those with a normal pancreas in enodosonography from January 2011 to January 2015. We used logistic regression models to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results: After adjustment for potential confounders, opium use (OR 1.91; 95% CI 1.06–3.43) and alcohol consumption (OR 4.16; 95% CI 1.86–9.31) were significantly associated with an increased risk of pancreatic cancer. We did not find an association between ever tobacco smoking and pancreatic cancer risk (OR 0.93; 95% CI 0.62–1.39). Conclusion: In our study, opium use and alcohol consumption were associated with an increased risk of pancreatic cancer, whereas cigarette smoking was not.