The impact of EUS in primary gastric lymphoma.

Gastric lymphoma is the most frequent site of gastrointestinal lymphoma and is accessible for endosonographic evaluation. Most primary gastric lymphomas are classified as mucosa-associated lymphoid tissue (MALT)-type lymphomas that develop in the course of chronic Helicobacter pylori infection. Endoscopic ultrasonography (EUS) is regarded to be the most accurate method for the local staging of gastric lymphoma, although scientific evidence is limited. In stage uEI1 low-grade lymphoma, EUS is able to predict a high chance for cure by H. pylori eradication. The significance of EUS elastography or EUS-guided fine-needle aspiration biopsy to diagnose nodal involvement has not been investigated in prospective series yet. Since high-grade lymphoma is always treated as a systemic disease, the impact of endosonographic staging is lower than in low-grade lymphoma. After treatment of primary gastric lymphoma, EUS produces conflicting results that are not as accurate as endoscopy with biopsy. Therefore, EUS is not mandatory during follow-up.