Adenocarcinoma of the esophagogastric junction: incidence, characteristics, and treatment strategies.

The incidence of adenocarcinoma of the esophagogastric junction (AEG) is dramatically increasing in Western countries, while it is not increasing in Eastern countries. Siewert type I tumors are observed less frequently in Eastern countries in comparison to Western countries. On the other hand, other clinicopathological features of AEG, including age, male-to-female ratio, pathological grade, tumor progression, and prognosis, are similar in Western and Eastern countries. Two surgical phase III trials have indicated that AEG type I should be treated surgically as esophageal cancer, while types II and III should be regarded as true gastric cancer. No phase III trials have demonstrated a significant interaction comparing hazard ratios for death between AEG and true gastric cancer in the subset analyses with regard to chemotherapy.