Gastric precancerous lesions: heading for an international consensus

As pathological criteria lie at the foundation for the classification of ma ny diseases, a crucial requisite for such classifications to be valid is th at their morphological basis be standardised. Inadequately standardised dia gnostic criteria result in unacceptable interobserver variation, a factor t hat may influence bath individual patient care and the evaluation of clinic al protocols. One of the most important goals in gastric diseases today is to establish w hether cure of Helicobacter pylori is an effective preventive measure again st gastric cancer. To tackle this issue it is necessary to measure reliably intermediate outcomes, specifically gastric atrophy and dysplasia. However , there is little agreement on what gastric atrophy and atrophic gastritis are, and treatment and follow up results obtained at one clinical centre ar e often radically different from those obtained at another. Similarly studi es that examine the fate of dysplastic lesions in the stomach show a great divergence of outcomes between Europe and North America and Japan, where th e concept of dysplasia has different connotations. To reach a consensus on the definitions and diagnostic criteria for atrophy and atrophic gastritis, a group of gastrointestinal pathologists and gastr oenterologists met in Houston, Texas, USA, in February 1998. Substantive pr ogress was made, but several problems remained, and a study aimed at resolv ing the issues that seem to stand in the way of an international agreement is currently underway. To fulfil the need for a broad discussion on the dia gnostic differences of gastric dysplasia and cancer between East and West, an international group of pathologists gathered in Padova, Italy in the spr ing of 1998. Their main objectives were: (1) to agree on the definitions of the spectrum of gastric preneoplastic lesions; (2) to establish an interna tional glossary for gastric precancerous lesions; and (3) to test the conse nsus and eventually generate guidelines useful to clinicians for the develo pment of management strategies. A consensus was achieved on the definition of gastric dysplasia as preinvasive neoplasia. Other validation studies are underway. The experiences achieved in the search for an international cons ensus on the phenotypes of atrophic gastritis and gastric dysplasia may rep resent a model in dealing with the new scenario of a modern evidence-based pathology.