Endomicroscopy and Gastric MALT-lymphoma

Extranodal marginal zone B-cell lymphoma (MZBL) of the mucosa associated lymphoid tissue (MALT-lymphoma) represents a distinct clinical entity and is the most common form of extranodal lymphoma, with a predilection for the stomach. About 90% of gastric MALT-lymphomas are associated with infection with Helicobacter pylori (HP) and eradication of the pathogen leads to regression of the tumor in a high percentage of patients at early tumour stages. Nevertheless, following complete remission after HP-eradication, the risk of relapse justifies lifelong follow-up examinations. Supported by recent findings at the investigators department, endoscopic controls should include a close examination of the small bowel, as relapses can involve different gastrointestinal sites. To continue the investigators diagnostic approach as well as to further improve the detection rate of MALT-lymphoma relapses, the investigators plan to introduce the novel confocal laser endomicroscope (CLE) into the diagnostic management of MALT-lymphoma patients. In the context of a prospective clinical pilot trial the investigators aim to establish MALT-lymphoma specific CLE-markers that can be used for the in vivo diagnosis of the disease. Comparing endomicroscopic findings, drawn from the stomach and small bowel of 50 MALT-lymphoma patients who will undergo staging or follow up endoscopies at the investigators department, to the histological evaluation of biopsy samples as present gold standard, the investigators want to determine whether CLE can provide reliable data for the accurate detection of MALT-lymphoma associated changes. Endomicroscopic aspects of patients with chronic gastritis, gastric adenocarcinoma and healthy subjects should serve as controls. In comparison to random biopsies which represent the current standard, the investigators aim to prove, whether endomicroscopy will find MALT-lymphoma lesions more accurately and thus help to spare patients unnecessary biopsies.