Gastroenterology & Endocrinology - Gastric Cancer
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Developments in Gastric Cancer Screening in Europe Written by Dr Charlene Deane, Dr Orlaith Kelly and Professor Colm O’Morain
intervention can effectively stop progression through this pathway thereby reducing unnecessary cancer deaths.
Dr Charlene Deane
Dr Orlaith Kelly
Professor Colm O’Morain
The current state of play: Gastric Cancer in Europe
screening program, which has resulted in a 5-year survival rate of up to 58%.
Professor Colm O’Morain, Clinical Lead in Gastroenterology & Hepatology and co-researchers Dr Orlaith Kelly, Consultant Gastroenterologist, Connolly Hospital and Dr Charlene Deane, Specialist Registrar in Gastroenterology. Having paired with Centric Healthcare, the Irish Defence Forces, the Construction Workers Health Trust and the Beacon HealthCheck, they will offer invitations to 30-34 year olds to be screened for Helicobacter pylori as part of pilot 1, a primary preventative strategy to gastric cancer.
In 2020, gastric cancer stood as the 6th most commonly diagnosed cancer, with 136,000 new cases diagnosed in Europe alone. Overall, Europe hosts the second-highest incidence of gastric cancer worldwide. While classically associated with Asian countries, European countries such as Portugal, Estonia, and Latvia report age-standardized rates comparable to China. Although the overall incidence of gastric cancer has declined in the past decade, the absolute number of new cases is anticipated to rise as the ageing population grows. In Ireland, the National Cancer Registry has captured approximately 600 new cases of gastric cancer per year (data from 2014.-2021), placing Irish males in the ‘intermediate risk’ category for gastric cancer. Unfortunately, gastric cancer still carries an extremely poor prognosis in Europe as it is frequently diagnosed at an advanced stage. Approximately two-thirds of Irish patients have stage 3 or 4 cancer at diagnosis, with an average 5-year survival rate of only 24%. In contrast, Japan, which has one of the highest incidences of gastric cancer worldwide, has implemented a successful
Gastric Cancer Screening and Europe’s Beating Cancer Plan In 2022, the European Commission published ‘Europe’s Beating Cancer Plan’. This report identified three cancers to target for the development of new national screening programmes: gastric, lung and prostate cancer. However, as it stands, the most cost-effective and feasible method of gastric cancer screening in a European population is largely unknown. Therefore, in response to the recommendations from the European Commission on gastric cancer screening, a research group known as TOGAS (Towards Gastric Cancer Screening Implementation in the European Union) was established. This group involves 20 partners across 14 different EU countries. This group will conduct three pilot projects funded by the European Union to provide initial data on the feasibility and cost-effectiveness of different screening methods in order to address this unknown. Ireland is one of the countries involved in the study and represents countries in Europe with a low-intermediate risk of gastric cancer. The Irish TOGAS team is being led by
MARCH 2024 • HPN | HOSPITALPROFESSIONALNEWS.IE
Screening mechanisms and existing Screening Programmes Pathogenesis of Gastric Cancer The Correa cascade defines the pathogenic progression from normal mucosa to atrophic gastritis, gastric intestinal metaplasia, low-grade dysplasia, high-grade dysplasia, and, ultimately, carcinoma. Screening is focused on the disruption this cascade through early detection and treatment of Helicobacter pylori, a known promoter of preneoplastic and neoplastic lesion development, known as primary prevention. Secondary prevention involves the early detection of precancerous and early cancerous lesions. Both approaches aim to intervene at a point where pharmacological or endoscopic
While no gastric cancer screening programme currently exists in Europe, the concept is not new. The Maastricht VI/ Florence consensus guidelines, the Science Advice for Policy by European Academics (SAPEA), and the International Agency for Research on Cancer (IARC) all recommend a ‘screen and treat’ approach in countries in Europe with intermediate and high risk of gastric cancer. Meanwhile, screening programmes have already been effectively implemented in several Asian countries for decades. The earliest gastric cancer screening programme was established in Japan in the 1950s. Since then, numerous randomised controlled trials have been conducted to evaluate the impact of primary and secondary prevention screening strategies on mortality rates. Evidence Supporting Primary Prevention Several randomised control trials have demonstrated the advantage of population screening and treatment of H.pylori in reducing gastric cancer risk. Ford et al. conducted a meta-analysis encompassing seven randomised control trials involving healthy adults with H.pylori infection who received either treatment or a placebo. The pooled analysis revealed an impressive relative risk reduction in gastric cancer mortality for those receiving treatment (RR 0.54; 95% CI 0.400.72), with little heterogeneity among the studies. According to this meta-analysis, the calculated number needed to treat to prevent one case of gastric cancer was 72, and the number needed to treat to prevent one cancerrelated death was 135. Numerous longitudinal observational studies also support the positive impact of population screening. The Matsu Island study, a notable prospective investigation, involved testing and treating adults over 30 for H.pylori. The study reported a 53% reduction in gastric cancer incidence, a 25% reduction in mortality, and no increase in the antibiotic resistance rate of
