Gastric cancer remains a prevalent disease worldwide with a poor prognosis. Helicobacter pylori plays a major role in gastric carcinogenesis. H. pylori colonization leads to chronic gastritis, which predisposes to atrophic gastritis, intestinal metaplasia, dysplasia, and eventually gastric cancer. Screening, treatment, and prevention of H. pylori colonization can reduce the incidence of gastric cancer. Other interventions that may yield a similar effect, although of smaller magnitude, include promotion of a healthy lifestyle including dietary measures, non-smoking, low alcohol intake, and sufficient physical activity. This chapter reviews interventions that can lead to a decline in gastric cancer incidence in high and low incidence countries.

Background and study aims: A recent international guideline recommends surveillance of premalignant gastric lesions for patients at risk of progression to gastric cancer. The aim of this study was to identify the role of the distribution and severity of premalignant lesions in risk categorization. Patients and methods: Patients with a previous diagnosis of atrophic gastritis, intestinal metaplasia, or low grade dysplasia were invited for surveillance endoscopy with non-targeted biopsy sampling. Biopsy specimens were evaluated by pathologists (four general and one expert) using the Sydney and the operative link for gastric intestinal metaplasia (OLGIM) systems, and scores were compared using kappa statistics. Results: 140 patients were included. In 37 % (95 % confidence interval [CI] 29 % – 45 %) the severity of premalignant lesions was less than at baseline, while 6 % (95 %CI 2 % – 10 %) showed progression to more severe lesions. Intestinal metaplasia in the corpus was most likely to progress to more than one location (57 %; 95 %CI 36 % – 76 %). The proportion of patients with multilocated premalignant lesions increased from 24 % at baseline to 31 % at surveillance (P = 0.014). Intestinal metaplasia was the premalignant lesion most frequently identified in subsequent endoscopies. Intestinal metaplasia regressed in 27 % compared with 44 % for atrophic gastritis and 100 % for low grade dysplasia. Interobserver agreement was excellent for intestinal metaplasia (k = 0.81), moderate for dysplasia (k = 0.42), and poor for atrophic gastritis (k < 0). Conclusions: Premalignant gastric lesions found in the corpus have the highest risk of progression, especially intestinal metaplasia, which has excellent interobserver agreement. This supports the importance of intestinal metaplasia as marker for follow-up in patients with premalignant gastric lesions.

Immunosuppressive drugs have been key to the success of liver transplantation and are essential components of the treatment of inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH). For many but not all immunosuppressants, therapeutic drug monitoring (TDM) is recommended to guide therapy. In this article, the rationale and evidence for TDM of tacrolimus, mycophenolic acid, the mammalian target of rapamycin inhibitors, and azathioprine in liver transplantation, IBD, and AIH is reviewed. New developments, including algorithm-based/computer-assisted immunosuppressant dosing, measurement of immunosuppressants in alternative matrices for whole blood, and pharmacodynamic monitoring of these agents is discussed. It is expected that these novel techniques will be incorporate into the standard TDM in the next few years.

Background: Methods: Results: Conclusion: