 To investigate the difference of the prevalence of t(11;18)(q21;q21)/API2-MALT1 fusion gene between gastrointestinal mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B cell lymphoma (DLBCL).     ///    API2-MALT1 fusion gene was detected by fluorescent in situ hybridization (FISH) using both dual fusion translocation and break apart probes.     ///    "The findings suggest that gastrointestinal tract MALT lymphomas with API2-MALT1 fusion gene may not transform into DLBCL, which may represent primary lymphoma or transformed API2-MALT1 negative MALT lymphomas.. "    ///    "API2-MALT1 fusion gene is a distinctive genetic aberration in MALT lymphomas, and is not present in DLBCL. "    ///    [Prevalence of API2-MALT1 fusion gene in gastrointestinal mucosa-associated lymphoid tissue lymphomas and diffuse large B cell lymphomas]..     ///    "Among gastrointestinal MALT lymphomas, API2-MALT1 fusion gene was found in 12 of 57 cases (21.1%, 10 gastric and 2 intestinal lymphomas). "