[Prevalence of API2-MALT1 fusion gene in gastrointestinal mucosa-associated lymphoid tissue lymphomas and diffuse large B cell lymphomas].
OBJECTIVE
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).


METHODS
A total of 57 cases gastrointestinal MALT lymphomas (38 gastric and 19 intestinal lymphomas), 32 DLBCL (28 gastric and 4 intestinal lymphomas) and 7 cases gastric DLBCL accompanied MALT lymphoma were collected from the Cancer Hospital of Fudan University. API2-MALT1 fusion gene was detected by fluorescent in situ hybridization (FISH) using both dual fusion translocation and break apart probes.


RESULTS
Among gastrointestinal MALT lymphomas, API2-MALT1 fusion gene was found in 12 of 57 cases (21.1%, 10 gastric and 2 intestinal lymphomas). In contrast, the fusion gene was not found in all 32 DLBCL and 7 gastric DLBCL with MALT lymphoma component. There was statistical significant difference between two groups (chi(2) = 9.383, P = 0.001).


CONCLUSIONS
API2-MALT1 fusion gene is a distinctive genetic aberration in MALT lymphomas, and is not present in DLBCL. 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.
Li
Bai-zhou
BZ
Department of Pathology, Cancer Hospital of Fudan University, Shanghai 200032, China.
Lu
Hong-fen
HF
Sheng
Wei-qi
WQ
Shi
Da-ren
DR
D002880:Chromosomes, Human, Pair 11; D002887:Chromosomes, Human, Pair 18; D005770:Gastrointestinal Neoplasms / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics / Q000378:metabolism*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000378:metabolism*; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism; D014178:Translocation, Genetic
C415943:API2-MALT1 fusion protein, human; D015514:Oncogene Proteins, Fusion