ABSTRACT
To detect chromosome translocation t(11;18) (q21;q21) and the nuclear expression of bcl-10 in gastrointestinal mucosa-associated lymphoid tissue (MALT) lymphoma in Chinese, a possible API2-MALT fusion transcript specific to t(11; 18) (q21; q21) in tumors from 42 cases of primary gastrointestinal lymphoma (29 cases of low grade MALT lymphoma, 13 cases of transformed MALT lymphoma) and 40 cases of diffuse large B cell lymphoma was examined by means of RT-PCR and proved by DNA-sequencing. Bcl-10 expression was examined by immunohistochemical method. The results showed that t(11;18) (q21;q21) was 14% positive in cases of low grade MALT lymphomas and 46% positive in transformed MALT lymphomas, but none in cases of DLBCL. Bcl-10 nuclear expression was seen 61% in low grade MALT and 69% in transformed MALT lymphoma. It was suggested that t(11;18) (q21;q21) was related to the prognosis and development of highly advanced MALT lymphoma but not relevant to DLBCL. Bcl-10 nuclear expressions were not significantly different between these two groups, which remains to be explained.