Stomach the first three chambers of which are all lined with oesophageal mucosa. In birds and crocodilians, the stomach is divided into two regions. Anteriorly is a narrow tubular region, the proventriculus, lined by fundic glands, and connecting the true stomach to the crop. Beyond lies the powerful muscular gizzard, lined by pyloric glands, and, in some species, containing stones that the animal swallows to help grind up food. In insects there is also a crop. The insect stomach is called the midgut. Information about the stomach in echinoderms or molluscs can be found under the respective articles. Stomach The stomach
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.