[Where and when does surgery achieve cancer prevention? Precancerous conditions of the stomach].

The early diagnosis of stomach diseases, that are high risk factors for cancer is of paramount importance, because the early cancer can be healed nowadays. Distinguish between precancerous lesions (adenoma, borderline-lesion, dysplasia III) and precancerous conditions (chronical atrophic gastritis, pernicious anemia, Ménétrier syndrome, hyperplasiogene polyps, the operated stomach, rarely ulcus ventriculi). Whereas precancerous lesions must be removed by diathermy-biopsy or operation, precancerous conditions need thorough endoscopic control. In operations for ulcerous disease the operation tactics must be chosen with the aim to avoid a carcinoma after gastric resection.