Clinical Gastroenterology Vol.20 No.1(15)

Theme Helicobacter pylori update
Title Current Theory on Indications for Helicobacter pylori Eradication Therapy for Gastric MALT Lymphoma
Publish Date 2005/01
Author Tsuneya Nakamura Department of Gastroenterology, Aichi Cancer Center Hospital
Author Masahiro Tajika Department of Gastroenterology, Aichi Cancer Center Hospital
Author Hiroki Kawai Department of Gastroenterology, Aichi Cancer Center Hospital
Author Takio Yokoi Pathology and Molecular Diagnosis, Aichi Cancer Center Hospital
Author Yasushi Yatabe Pathology and Molecular Diagnosis, Aichi Cancer Center Hospital
Author Shigeo Nakamura Pathology and Molecular Diagnosis, Aichi Cancer Center Hospital
[ Summary ] Gastric MALT lymphoma was divided into three groups according to the combination of responses to H. pylori eradication and detection of API2-MALT1 fusion : Group A, eradication-responsive and API2-MALT1 fusion-negative : Group B, eradication-nonresponsive and API2-MALT1 fusion-negative ; and Group C, eradication-nonresponsive and API2-MALT1 fusion-positive. Group A tumors were characterized by positive H. pylori infection, low clinical stage and superficial involvement of the gastric wall (restricted to the mucosa or submucosa). Group B tumors were clinically characterized by an endoscopic protrusion, frequent nodal involvement, advanced clinical stage, and deep gastric wall involvement, as well as being histologically characterized by increased large cell components. Group C tumors showed low H. pylori infection rates and an endoscopic cobblestone appearance. H. pylori eradication therapy for gastric MALT lymphoma is recommended for Group A. Specific gene alterations for Group B have not been found at present. It is as to controversial whether gastric MALT lymphoma with negative H. pylori infection, deep gastric wall involvement, protruding type endoscopic appearance or positive diffuse large cell components should be treated with H. pylori eradication. However, some cases did show responsiveness to H. pylori eradication therapy, including those examined in our study as well as in the literature, which implies that API2-MALT1 negative MALT lymphoma may merit separate consideration because of the pragmatic therapeutic approach.
back