From 1944 to 2004, 11,261 patients with upper gastrointestinal carcinomas (6215 gastric; 5046 esophageal) were treated at The University of Texas MD Anderson Cancer Center. Of these, 5112 (2393 gastric; 2719 esophageal) underwent a definitive treatment at MD Anderson. Overall survival (OS) significantly improved at 5 and 10 years over this 60-year interval. Absolute OS improvements at 5 years were 20.3% for gastric cancer (11.8 versus 32.1%, p < .0001) and 24.9% for esophageal cancer (2.3 versus 27.2%, p < .0001).
In the United States, an estimated 21,130 new cases of gastric cancer were diagnosed in 2009, with 10,620 deaths (1). According to the Surveillance Epidemiology and End Results (SEER) 17 (2000–2006) database, only 24% of gastric cancers are confined to the stomach (localized); 31 to 32% of newly diagnosed cases have spread beyond the stomach into the regional lymph nodes (regional) or other organs (distant), respectively (2). Gastric cancer predominantly affects men, at a ratio of 2:1. The median age at diagnosis is 71 years (2). The 5-year OS rate is 25.7%, which has not changed significantly over the past 30 to 40 years (2). Surgery is still the only chance for cure, and survival can be improved with multimodality therapy.
The incidence of gastric carcinoma varies widely, both worldwide and within individual country. The highest incidence (>20 per 100,000 in men) is in Japan, China, Eastern Europe, and South America, while the lowest incidence (<10 per 100,000 in men) is in North America, parts of Africa, and Southern Asia (3). In the United States, gastric cancers occur at a median age of 69 years for men and 73 for women (2). African Americans, Hispanic Americans, and Native Americans are 1.5 to 2.5 times more likely to develop gastric cancer than whites (4). On the basis of SEER 2002-2006 data, the age-adjusted incidence of gastric cancer is 7.9 per 100,000 men and women per year (2).
In the United States, the incidence of gastric cancer has been decreasing over the past several decades, reflecting a significant reduction in distal (body and antrum) disease. The reason for the decline is not known but may be related to dietary habits, food preservation, and improved surgical morbidity and mortality rates. However, the incidence of proximal stomach and gastroesophageal junction (GEJ) adenocarcinomas has steadily increased at a rate exceeding that of any other cancers except melanoma and lung cancer (5). Observational studies suggest that proximal cancers have a different pathogenesis than do distal cancers (6). Potential causes of distal gastric cancers include Helicobacter pylori infection or E-cadherin expression loss, whereas proximal gastric cancer may behave similarly to distal esophageal and GEJ cancers, which progresses from Barrett metaplasia to dysplasia to invasive adenocarcinoma. Only 24% of newly diagnosed gastric cancers are localized. The 5-year survival rate of patients with metastatic disease is less than 5%. Thus, even in the United States, despite decreasing incidence, gastric cancer remains a public health concern because of ...