Controversies and consensus in the diagnosis, work-up and treatment of gastric lymphoma: An international survey

Background: Variations in diagnostic criteria and staging procedures in cancer patients have important consequences for patient selection and often preclude meaningful comparison of published series. In gastric lymphoma, these effects will play a role, since diagnostic criteria are controversial. Moreover, staging procedures and therapeutic choices are influenced by insights from different clinical specialisms. Methods. To review the management of gastric lymphoma, formatted questonaires were mailed to leading institutes with a special interest in this field in Europe, the United States and Japan. Results. Nineteen centers aggreed to contribute. Minimum histological criteria varied among pathologists with a notable influence of the classification system used in the different countries. Detailed evaluation of the lymphoma distribution in the gastric wall and routine staging of the GI-tract differed between groups leaded by medical oncologists and gastroenterologists. This results in basically different patient selections and bias in treatment outcome. Similar effects were recorded for the role of gastric resection and radiotherapy. Conclusions: This study gives insight in the basis of the decisions that result in different approaches in the management of gastric MALT-NHL and in the effects for patient selection and treatment results and may help in the design of future clinical trials.