2. Gastric Cancer Remains the most common malignancy in Japan and China. It was the first-ranked malignancy in the United States in the 1930s to 1940s, but it has rapidly declined in more recent decades

3. Gastric neoplasms are predominantly Malignant, and nearly 90 to 95 % of cases are adenocarcinomas. Less frequently observed malignancies Include lymphomas, especially non-Hodgkin’s lymphoma, as well as sarcomas, such as leiomyosarcoma.

4. ADENOCARCINOMA OF THE STOMACH Epidemiology: There is great geographic variation in the incidence of gastric cancer worldwide, strongly indicating that environmental factors influence the pathogenesis of gastric carcinogenesis

5. Gastric adenocarcinoma localized to the distal stomach has declined, the incidence rate of proximal gastric, gastro- esophageal adenocarcinomas has been steadily increasing in the United States

6. ThTh The incidence of gastric cancer is variable in different parts of the word. In japan 75 to 100 new cases per 100,000 per year. other areas of high prevalence include chile and Scandinavia.

7. Epidemiologic studies of high-risk populations have also suggested that genotoxic agents such as N-nitroso compounds may play a role in gastric tumorigenesis. N-nitroso compounds can be formed in the human stomach by nitrosation of ingested nitrates, which are common constituents of the diet.

8. Etiology: Risk factors for the development of gastric adenocarcinoma can be divided into environmental and genetic factors as well as precursor conditions

9. اتيولوژي كانسر معده 1- عوامل محيطي 2- عامل ژنيتيك 3- عوامل مستعد كننده

10. Typically, gastric cancer occurs between ages 50 to 70 years and is uncommon before age 30 years. The rates are higher in males than females by 2 to 1.

11. The achlorhydria associated with gastritis related to H. pylori, pernicious anemia, or other causes favors the growth of bacteria capable of converting nitrates to nitrites.

12. In united states is 7 cases per 100,000 per yr. It is the 10 th most common cause of cancer in USA. Increase in incidence of adnocarcinoma of the distal esophagus and cardia of the stomach.

13. Patients with familial adenomatous polyposis also have a risk approximately three time higher than that of the general population of developing gastric cancer. ( عوامل مستعد كننده )

14. Blood group antigens have also been associated with gastric cancer. With the incidence highest in persons with blood type A and lowest in persons with blood type O. ( عوامل مستعد كننده )

15. Etiology : Dietary factor: Salted Smoked fish Pickled vegetables Well-cooked meats Fruit and fiber have been found to be protective. Vit C is thought to protect against some of the mutagens present especially in smoked foods Etiology : Dietary factor: Salted Smoked fish Pickled vegetables Well-cooked meats Fruit and fiber have been found to be protective. Vit C is thought to protect against some of the mutagens present especially in smoked foods

18. Atrophic gastritis and gastric cancer share a number of common environmental risk factors. It is likely that atrophic gastritis and intestinal metaplasia represent intermediary steps to gastric cancer. ( عوامل مستعد كننده )

19. . Pernicious anemia Peptic ulcer disease Iron deficiency N-nitroso compounds H2 antagonists ( عوامل مستعد كننده )

20. Aspirin Nonsteroidal anti- inflamatory Drugs have been associated with a decreased risk of gastric cancer. ( عوامل مستعد كننده )

21. بررسي توزيع فراواني متغيرهاي دموگرافيك در بيماران مبتلا به سرطان در 5 سال ( 1369-1374 ) در استان اصفهان طرح پژوهشي شماره 1010

22. Skin Stomach Lymphoma bladder blood Colon esophagus prostst rectum lung Cancer in Men

23. skin Breast Stomach Lymphoma Blood Colon esophagus rectum Lung Othrers نسبت وفور سرطان در زنان