The causation of 'peptic ulcer' is multifactorial. Loosely linked, 'peptic ulcer' is a term which covers most duodeno-gastric ulcers. Duodenal ulcer is rather different from gastric ulcer. The former is associated with infection with H. Pylori and ulceration associated with stomach acid secretion and stress. The latter, often associated with low gastric acid levels and H. Pylori, can, with time can lead to carcinoma of the stomach. I used to see quite a few chronic gastric ulcers - they are rare today. Michael.