Table 1.

Cytogenetic abnormalities in gastric MALT lymphomas, along with their reported frequencies, known clinical implications and available assays for their detection.

Abnormality	% Gastric MALT	Clinical implications	Available assay(s)
t(11;18)(q21;q21)	Up to 25%	Antibiotic resistance	FISH; RT-PCR; BCL10 IHC (nuclear)
t(14;18)(q32;q21)	Up to 5%	Unknown	FISH; PCR; MALT1 and BCL10 IHC (cytoplasmic/perinuclear)
t(1;14)(p22;q32)	Rare	Antibiotic resistance	BCL10 IHC (nuclear)
t(3;14)(q27;q32)	Rare	Reported in DLBCL with concurrent MALT	FISH (break-apart); BCL6 IHC (only 25%–30%)
Trisomies	5%–65%, depending on series	3q27 most common; associated with high-stage disease	FISH