Role of the Endoscopic Ultrasonography in the Management of Gastric Lymphomas: Our Experience and Review of Literature

The stomach is the most common extranodal site of non-Hodgkin lymphoma (NHL) accounting for 7.1 to 10% of adult NHL (Danzon et al., 2009). The most frequent histotypes of gastric lymphomas are MALT lymphomas that arise from the stomach-associated lymphatic tissue and the Diffuse Large B-Cell Lymphoma (DLBCL) (Koch et al., 2001). Several studies have observed that in recent years both gastric-NHL incidence and survival are increasing (Danzon et al., 2009). Furthermore, the management of gastric lymphomas has changed during the last two decades with a strong reduction of surgery in flavor to conservative treatments (Yoon S.S. et al., 2004). Indeed, the progress in biologic understanding of the pathogenesis, the introduction of Helicobacter pylori (HP) eradication therapy and the introduction of conservative treatment have definitely changed the approach to the disease and gastrectomy is no longer the first choice (Fischbach, 2010). The role of HP is a consolidated finding and several studies have confirmed that a simple antibiotic therapy (AT) for HP eradication is an effective treatment for MALT lymphomas with limited extension (Fischback et al., 2004), whereas, for advanced gastric lymphomas, the golden standard of treatment is the antineoplastic chemotherapy with alkylating agents in monochemotherapy such as Clorambucil for MALT lymphomas and polichemotherapy together with immunotherapy such as R-CHOP for DLBCL (Zucca & Dreyling, 2010). The loco-regional staging of gastric lymphomas with limited disease is important in order to better understand how to treat patients and endoscopic ultrasound (EUS) technique plays in this context a pivotal role by giving information for the prevision of response to HP eradication therapy since this therapy has shown to induce a high percentage of histological remission (up to 88%) when the disease is confined to mucosa and submucosa (Caletti et al., 2002). However, the importance of EUS in assessing the response to treatment and the follow-up is controversial. During the last decade, some reports indicated the importance of EUS in evaluating the response to treatment and also in long-term follow-up of gastric lymphomas with limited disease (Yeh et al., 2003), whereas other recent reports indicated the importance of EUS also in the follow-up of local-advanced MALT lymphoma (Pavlović et al., 2005). That notwithstanding, the latest ESMO clinical guidelines for diagnosis, treatment and follow-up