Operative link for gastritis assessment vs operative link on intestinal metaplasia assessment

Aim: To compare the reliability of gastritis staging systems in ranking gastritis-associated cancer risk in a large series of consecutive patients.

Methods: Gastric mucosal atrophy is the precancerous condition in which intestinal-type gastric cancer (GC) most frequently develops. The operative link for gastritis assessment (OLGA) staging system ranks the GC risk according to both the topography and the severity of gastric atrophy (as assessed histologically on the basis of the Sydney protocol for gastric mucosal biopsy). Both cross-sectional and long-term follow-up trials have consistently associated OLGA stages III-IV with a higher risk of GC. A recently-proposed modification of the OLGA staging system (OLGIM) basically incorporates the OLGA frame, but replaces the atrophy score with an assessment of intestinal metaplasia (IM) alone. A series of 4552 consecutive biopsy sets (2007-2009) was retrieved and reassessed according to both the OLGA and the OLGIM staging systems. A set of at least 5 biopsy samples was available for all the cases considered.

Results: In 4460 of 4552 cases (98.0%), both the high-risk stages (III + IV) and the low-risk stages (0 +I + II) were assessed applying the OLGA and OLGIM criteria. Among the 243 OLGA high-risk stages, 14 (5.8%) were down-staged to a low risk using OLGIM. The 67 (1.5%) incidentally-found neoplastic lesions (intraepithelial or invasive) were consistently associated with high-risk stages, as assessed by both OLGA and OLGIM (P < 0.001 for both). Two of 34 intestinal-type GCs coexisting with a high-risk OLGA stage (stage III) were associated with a low-risk OLGIM stage (stage II).

Conclusion: Gastritis staging systems (both OLGA and OLGIM) convey prognostically important information on the gastritis-associated cancer risk. Because of its clinical impact, the stage of gastritis should be included as a conclusive message in the gastritis histology report. Since it focuses on IM alone, OLGIM staging is less sensitive than OLGA staging in the identification of patients at high risk of gastric cancer.