**1. Introduction**

The incidence of gastric cancer (GC) has been declining globally in the last decades. This slow, yet steady decrease in incidence and mortality rates has been attributed to improved medical treat‐ ment of peptic ulcers and chronic gastritis, development of protocols for *Helicobacter pylori* eradi‐ cation, lifestyle changes, and introduction of safer food preservation methods [1, 2]. However,

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it is also important to note that the total incidence of most common gastric malignancy, adeno‐ carcinoma, varies by geographic areas up to 20‐fold between the highest and the lowest risk populations. The high risk areas are in certain Asian regions, such as Japan, China and Korea, followed by Eastern Europe and some countries in South America [3]. Low‐risk populations are located in North America, India, the Philippines, most countries in Africa, some Western European countries and Australia [4]. Up to 10% of GCs arise as a consequence of inherited can‐ cer predisposition syndromes, such as Li‐Fraumeni syndrome, Lynch syndrome, Peutz‐Jeghers syndrome, hereditary breast and ovarian cancer, MUTYH‐associated adenomatous polyposis (MAP), familial adenomatous polyposis (FAP), juvenile polyposis syndrome and PTEN hamar‐ toma tumor syndrome (Cowden syndrome) [5, 6]. Genetic counselling and mutation analyses, regular endoscopic surveillance and screening of the at‐risk family members and risk‐reduc‐ tion surgery of stomach have greatly improved management of patients with hereditary muta‐ tions predisposing to the development of hereditary GC [5, 7]. However, approximately 90% of GCs are sporadic and typically occur in elderly population [6, 8]. Despite improvements in the diagnostic procedures, most cases of sporadic GCs are still detected at advanced stages due to the lack of specific symptoms associated with the early phases of tumor development. Consequently, high mortality rates attributable to advanced GC contribute significantly to the public health burden worldwide. The estimated overall 5‐year relative survival rates of patients with advanced GC in developed countries are still low, around 30% [9]. An additional reason for concern is the demographic transition to the older population accounting for the significant pro‐ portion of population in developed countries [10]. This demographic shift will have an impact on health services, as the number of people over the age of 65, who comprise the highest risk group for the development of sporadic GC, has been steadily increasing in these countries. The challenge most countries are facing at the present time is how to improve the healthy life expec‐ tancy with regard to early detection of chronic and degenerative diseases, including cancers.
