IV: OLGA IV was 56% and OLGA III was 28%. None of the patients with gastric atrophy were OLGA 0. In contrast, most patients with duodenal ulcer were in lower OLGA states: 22% were OLGA 0, and 61% were OLGA I (35). These two studies consistently showed that patients with gastric cancer have higher OLGA stages than those without GC. Sipponem and Graham (36) have also shown that the risk for GC in OLGA Stage IV patients with different phenotypes of atrophic gastritis was from 10 to 90 times greater than for individuals with normal mucosa. This year Rugge et al. published the first evidence showing that the OLGA staging system provides information relevant to the pathological outcome of chronic gastritis and thus for the management of patients (37). They found that all gastric intraepithelial neoplasias were consistently associated with OLGA III and/or IV. Similarly they found a significant inverse correlation between levels of pepsinogen I, the pep- sinogen I/II ratio and OLGA system stages of severity.On the other hand, a classic study of risk stratification by Ohata et al. (15) showed that atrophic gastritis with intesti- nal metaplasia carries a major risk for GC. For almost eight years these authors followed 4,655 healthy asymptomatic individuals who were diagnosed with H. pylori infection by serology and with gastric atrophy based on serum pepsino- gens. During follow up 45 patients developed GC (overall incidence rate of 126/100,000). No patients who were nega- tive for H. pylori negative and for atrophy developed GC. The hazard ratio (HR) for GC in infected patients increased progressively Patients who were positive for H. pylori, but negative for atrophy, had an HR of 7.13 (95% CI 0.95 to 53),. Patients who were positive for both H. pylori and atrophy had an HR of 14.8 (95% CI 1.96-107). Finally, patients who were negative for H. pylori, but had severe atrophy with IM, had an HR of 61.8 (95% CI 5.6-682). The important results of this study confirm that the GC is very rare in the absence of H. pylori, but that this organism alone, without other factors, is not associated with gastric carcinogenesis. Among those other factors gastric atrophy and IM are the most severe and have the greatest risk of GC.The CG rate per 100,000 people was totally different for each group. It was zero in Group I, zero, 107 in group II,238 in Group III, and 871 in group IV. The number endos- copies conducted in one year to find one case of GC was0/1,000 endoscopies for Group I, 1 / 1,000 for Group II,1/410 for Group III, and 1/114 for Group IV (38). The findings from these studies suggest that patients with Stage IV should be carefully examined and followed for timely detection of CG. Some experts (38) recommend the following guidelines for monitoring: OLGA Stage IV should have an endoscopic examination every year, OLGA Stage III every two years, and OLGA Stage II should have an endoscopic examination every five years. OLGA Stage I patients do not need to be monitored. Also, risk for CG can be stratified (38) as follows. No risk: patients without H. pylori infection and OLGA 0. Minimal risk: atrophic gastritis, OLGA I. Moderate risk: OLGA II. Increased risk: OLGA III and IV. Clearly, to corroborate this prospective studies are needed. However, this interpretation of the different results clearly gives better guidance about how to proceed with these patients than do previous approaches.ConClusionsGiven the available information, one can conclude that we no longer need to discuss the association between H. pylori and GC. The focus should now be on determining the mechanisms of carcinogenesis and on identifying patients at increased risk of GC. Of course, the ideal would be to prevent GC, Theoretically this could be achieved when there are no H. pylori, and when enough time has passed so that no atrophy or IM persists after the infection has been eradicated (39). The best strategy would be real secondary prevention of GC (40) through the eradication of H. pylori (41, 42) coupled with risk stratification of atrophy to guide monitoring of patients. This stratification should be based on the OLGA system or another system developed in the future (such as the recently described OLGIM system that replaces gastric atrophy with intestinal metaplasia) (43). In our environment we have found that, among patients with uninvestigated dyspepsia, GC is identified after 30 years of age with a prevalence of 9% (44). Consequently, the local strategy could be upper endoscopy for patients with dyspepsia, investigation of the possibility of H. pylori infection, eradication if present, verification of elimina- tion, risk stratification based on OLGA, and individual follow-up of patients according to this information. Today, the OLGA system is an important guide or “roadmap” for decision making by gastroenterologists and their patients. Pathology reports should use this system for GC risk stra- tification. Current knowledge im
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