[Gastric cancer - current state of the problem. Part I. Epidemiology. Pathology. Classification. Staging].

Gastric cancer is still rampant in several countries around the world. His incidence exhibits significant geographic variability. The disease is most common in East Asia, and high rates of occurrence have also been reported in Central and South America, Eastern Europe, and parts of the Middle East. In Japan, gastric cancer remains the most common type of cancer among men. The overall incidence of this condition has decreased in the past few decades, nonetheless, gastric cancer remains a major public health issue as the fourth most common cancer and the second leading cause of cancer death worldwide. The reported reductions in gastric cancer mortality may be linked to better refrigeration and a concomitant decrease in the intake of salted, pickled, smoked, and chemically preserved foods; however, this link remains controversial. Another relevant change in the epidemiology of gastric cancer is a shift in the distribution of primary lesion sites within the stomach. In the first quarter of the 20th century, two thirds of gastric cancers were located in the antrum and the prepyloric area, and only 10% arose in the cardia or the esophagogastric junction. Since the 1970's, however, adenocarcinoma of the proximal stomach has become increasingly common.