The t(14;18)(q32;q21)/IGH-MALT1 translocation in gastrointestinal extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma).
OBJECTIVE
Studies have indicated that the t(14;18)(q32;q21)/IGH-MALT1 translocation is present in extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma). However, only a few studies have investigated the incidence of t(14;18)/IGH-MALT1 in primary gastrointestinal MALT lymphomas or in diffuse large B-cell lymphomas (DLBCL). The overall significance of t(14;18)/IGH-MALT1 in gastrointestinal MALT lymphomas is not clear. We examined 41 gastrointestinal MALT lymphoma and 23 DLBCL cases, with the aim of further understanding the role of t(14;18)/IGH-MALT1 in these diseases.


RESULTS
Fluorescence in-situ hybridization (FISH) assays for the detection of t(14;18)/IGH-MALT1 and t(11;18)(q21;q21)/API2-MALT1, along with immunostaining and histological evaluations, were performed on selected cases. Of the 64 analysed cases, one gastric MALT lymphoma and one colonic MALT lymphoma were positive for t(14;18)/IGH-MALT1.


CONCLUSIONS
We describe what are, to our knowledge, the first reported primary colonic MALT lymphoma carrying t(14;18)(q32;q21)/IGH-MALT1, and one of the few reported cases of gastric MALT lymphoma with this translocation. As this translocation is seen in only a few gastrointestinal MALT lymphomas, it is not useful as a diagnostic marker for routine clinical services. Although these findings suggest that t(14;18)/IGH-MALT1 is a rare molecular event in gastrointestinal MALT lymphomas and DLBCLs, further studies to elucidate the role of this genetic alteration in these diseases are indicated.
Division of Molecular Pathology, The Joint Pathology Centre, Bethesda, MD, USA.
Shimin
S
Zhang
Minqi
M
Wei
Qi
Q
Liang
Daisy
D
Johnson
Nancy
N
Dow
Ann
A
Nelson
Nadine
N
Aguilera
Aaron
A
Auerbach
Guanghua
G
Wang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D005260:Female; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D014178:Translocation, Genetic; D055815:Young Adult
C548564:IGH-MALT1 fusion protein, human; D015514:Oncogene Proteins, Fusion
MALT lymphoma; fluorescence in-situ hybridization; t(11;18)(q21;q21); t(14;18)(q32;q21)/IGH-MALT1