tailieunhanh - Ebook Cancer epidemiology and prevention (4/E): Part 2

(BQ) Part 2 book “Cancer epidemiology and prevention” has contents: Stomach cancer, small intestine cancer, biliary tract cancer, liver cancer, hodgkin lymphoma, multiple myeloma, bone cancers, soft tissue sarcoma, endometrial cancer, ovarian cancer, bladder cancer, and other contents. |  593 31 Stomach Cancer CATHERINE DE MARTEL AND JULIE PARSONNET OVERVIEW Stomach cancer is the fifth most common incident cancer worldwide and the third leading cause of cancer death. Almost half of the world’s cases occur in Asia, with 42% in China alone. Although the incidence and mortality from stomach cancer are decreasing, global disease burden remains high. Moreover, the absolute number of cases continues to rise because of population aging. Adenocarcinomas comprise over 90% of gastric malignancies. The adenocarcinomas are further classified according to anatomic location (cardia vs. non- cardia), histology (., intestinal or diffuse, signet ring or non- signet ring) and most recently by molecular classification. Adenocarcinomas in the stomach’s body and antrum are usually caused by chronic infection with Helicobacter pylori (H. pylori); the incidence of these tumors is decreasing worldwide. Cardia tumors have epidemiological characteristics more similar to those of esophageal adenocarcinoma; the incidence of these tumors is increasing, particularly in high- income, Western countries. New molecular classification systems have been proposed based on investigations of tumors in high- income countries. The Cancer Genome Atlas Program has identified four molecular subtypes: (1) tumors positive for Epstein- Barr virus; (2) those marked by microsatellite instability; (3) genomically stable tumors; and (4) tumors with chromosomal instability and extensive somatic copy- number aberrations. These subtypes have not yet been integrated into etiologic and descriptive studies. The most promising public health strategy for preventing gastric cancer is the eradication of H. pylori with antibiotics. This approach is currently being tested in randomized clinical trials. INTRODUCTION At the dawn of the twentieth century, stomach cancer represented an astonishing one- third of all cancers, approximately 1% of hospital admissions, and 2% of all deaths investigated by .