7236 Endosonographic evaluation of low-grade gastric malt lymphoma- miniprobe sonography versus conventional endoscopic ultrasound.

Abstract

Background: The application of endosonography (EUS) has been considered as a valuable tool in the evaluation of low-grade gastric MALT lymphoma. Miniprobe sonography (MPS) has been applied more frequently in recent years for various GI diseases. The aim of this study is to evaluate the role of miniprobe sonography (MPS) in the evaluation of low-grade gastric MALT lymphoma in comparison with the conventional EUS for the diagnosis and long-term follow up. Methods: From January 1994 to July 1999, 16 patients were proved to have gastric low-grade MALT lymphoma. Endosonography was performed for either initial diagnosis or follow up with conventional echoendoscope (Olympus UM20) in 7 patients and with miniprobe (Olympus UM2R) in 9 patients. Helicobacter pylori treatment was given for all the positive patients. The related endoscopic, endosonographic patterns and clinical outcomes were reviewed. Results: H. pylori was found in 12 (75%) of 16 patients. The initial endoscopic patterns include shallow ulcers and/or atypical mucosal relief in 12 patients, large ulcers in 2 patients and polypoid folds in 2 patients. The EUS findings include normal wall thickness in 2 patients, predominantly mucosal thickening in 5 patients, predominantly submucosal thickening in 5 and mixed mucosal and submucosal thickening in 4 patients. Mild proper muscle infiltration was noted in only 1 patient. Complete regression was observed in 6 (37.5%) patients, partial regression in 5 (31.2%) patients and no response in 5 (31.2%) patients. The full range of infiltration in each patient can be detected efficiently by either conventional echoendoscope or MPS. No peri-gastric lymph node was detected by both modalities. The application of MPS allows the performance of endoscopy and EUS to be completed in a single session. Such simplicity obtains much better patient's compliance in the long-term follow-up courses. MPS also provides accurate correlation between endoscopic and sonographic findings and helps to find the best location for endoscopic biopsy. Conclusions: MPS is as equally effective as conventional EUS in the evaluation of the infiltration of gastric MALT lymphoma and has several advantages over conventional EUS. The advantages of MPS include excellent endoscopic and endosonographic correlation, better patient's compliance and physician's convenience. MPS is a more useful tool than conventional EUS in the diagnosis and long-term follow up of low-grade gastric MALT lymphoma.