Overexpression of COX-2 and clinicopathological features of gastric cancer: a meta-analysis

According to the latest global cancer statistics, gastric cancer is the fifth most common malignant tumor in the world, ranking behind breast cancer, prostate cancer, lung cancer and colorectal cancer (1). Also, the World Health Organization (WHO) indicates that the annual incidence of gastric cancer is 13.86/100,000 and there are about 1.39 million cases and 1.09 million deaths every year in the world (1). More than 70% of patients are from developing countries (456 thousand male, 221 thousand female), and more than 50% are from East Asia, especially China (2). The number of gastric cancer cases and deaths in China accounted for 42.6% and 45.0% of the global gastric cancer morbidity and deaths, respectively, ranking fifth in morbidity and sixth in mortality among 183 countries in the world. China has a high incidence of gastric cancer, accounting for about 50% of the world's morbidity and deaths (1,3,4). The occurrence of gastric cancer is a multi-step and multistage process based on the activation of multiple protooncogene and inactivation of anti-oncogene, the former acts on the cell growth, differentiation and metabolism through its expression products, leading to canceration (5,6). Original Article