Stomach "mouth". The words "gastro-" and "gastric" (meaning related to the stomach) are both derived from the Greek word "gaster" (, meaning "belly"). Although the precise shape and size of the stomach varies widely among different vertebrates, the relative positions of the oesophageal and duodenal openings remain relatively constant. As a result, the organ always curves somewhat to the left before curving back to meet the pyloric sphincter. However, lampreys, hagfishes, chimaeras, lungfishes, and some teleost fish have no stomach at all, with the oesophagus opening directly into the anus. These animals all consume diets that either require little storage of
Tumor of the stomach Tumor of the stomach A gastric tumor is a tumor of the stomach. It can be benign or malignant (gastric cancer). The gastric mucosa is composed of columnar epithelium arranged with pits known as crypts. There are several types of cells that make up gastric mucosa that give rise to gastric tumours: adenocarcinomas comprise 90% of these. Gastric tumours are mostly metastatic and are usually detected at a late stage. They occur more commonly in men than women in the 6th decade of life. Risk Factors 1. Smoking 2. Helicobacter pylori infection. 2. Diet low in fruits and vegetables. 3.