Endoscopic diagnosis completed by biopsy achieved remarkable accuracy. New trends--endoscopy with the use of ultrasound orange red porphyrin fluorescence elicited by blue light e. g. krypton laser and strip biopsy not only greater accuracy of endoscopic methods but also open up new therapeutic possibilities. Histochemical and histoenzymatic methods allow to classify histological findings of the norm (presence of pepsinogen and neutral glycoprotein) of atrophic gastritis with intestinal metaplasia (acid glycoprotein, activity of sucrose, alkaline phosphatase-AP, leucin-aminopeptidase-LAP) and of dysplasia (presence of sulfomucin, decrease of AF, LAP, sucrose and trehalase activity) and to divide them into well defined groups. We are able to distinguish which mucosal changes are suspect, we know that malignant transformation can after a certain period of time be expected approximately 2-14% yet we still do not know whether the period from dysplastic change to malignant transformation is not longer than malignant change in resected stomach. Epidemiologic and experimental data gives us enough reasons for dietary and chemopreventive measures (apart of other treatment) especially in risk groups patients.

Keywords: Humans; Stomach Neoplasms /diagnosis/; Time Factors