Changes of Esophagogastric Junctional Adenocarcinoma and Gastroesophageal Reflux Disease Among Surgical Patients During 1988–2012: A Single-institution, High-volume Experience in China

Gastric and esophageal cancers are 2 of the most common malignancies in the world. More than 70% of gastric cancer cases and deaths occur in developing countries, and most occur in Eastern Asia.1 There have been distinct changes in the incidences of cancer at different anatomical subsites of the stomach in Western countries.2–4 Many population-based studies showed that the incidence rates of adenocarcinoma of the esophagus and esophagogastric junction (EGJ) were increased in Western countries and Asian countries, such as Japan and Korea.2–8 Although squamous cell carcinoma of the esophagus is still predominant, more than half of newly diagnosed tumors are adenocarcinoma of distal esophagus and EGJ in Western countries and Japan.2–4,6 Incidence of adenocarcinoma at the upper third of the stomach and EGJ has increased over the past 2 decades, with a rate which has exceeded that at any other site of stomach.2,4 In contrast, incidence of adenocarcinoma at distal stomach has gradually declined over the past 50 years.3 However, investigations on changes of esophagogastric junction adenocarcinoma (EGJA) in China remains sparse. Gastroesophageal reflux disease (GERD) was one of the most common gastrointestinal diseases in Europe and the United States with prevalence rates of 10% to 25% in population-based studies.9,10 Reports from many other regions have also demonstrated an increase in the prevalence of GERD.11,12 Some of those with GERD may develop Barrett esophagus, which can lead to esophageal adenocarcinoma. In addition, the prevalence of GERD was also found to be closely associated with the risk of EGJA in some Asian countries.13 Patients with Barrett esophagus need more intensive screening and surveillance for EGJA. Therefore, it is necessary to understand the changes of GERD and EGJA in China over time. However, there were rare reports that simultaneously assessed the trends of EGJA and GERD in China over time. A study by Zhou et al14 showed that there was an increasing trend of gastric cardia cancer over a 12-year period in a northwest province of China. With the increasing acceptance of Siewert's definition of EGJA, more and more researchers have studied this kind of clinicopathological entity.15 However, there have been few investigations into the change over time of 3 subtypes of EGJA in China. The volume of surgeries done for gastric and esophageal cancers at our institution is large, and the sources of patients come from the Western China, which may serve as a reference for a large population-based study. In this study, we aimed to evaluate the changes of clinicopathological features and surgical treatment of EGJA on the basis of the Siewert classification16 and the prevalence of GERD among the surgical patients with EGJA in a high-volume Chinese hospital during 1988–2012.