It is known that geographical differences in the prevalence and etiopathogenesis of gastric cancer exist across the world. Eastern Europe and East Asia are two of the largest endemic areas of gastric cancer in the world, yet there are few studies comparing its features in these two regions. Based on our experience and literature data, we performed a review that is mainly focused on the etiology and pathogenesis of sporadic gastric cancer and its geographic particularities. Geographic prevalence of specific Helicobacter pylori strains is also synthesized. The pathogenesis of gastric cancer in patients from countries of the authors, respectively Japan, Romania, Hungary and Poland, is particularly examined.