Exclusive detection of the t(11;18)(q21;q21) in extranodal marginal zone B cell lymphomas (MZBL) of MALT type in contrast to other MZBL and extranodal large B cell lymphomas.
Extranodal mucosa-associated lymphoid tissue (MALT)-type lymphomas and nodal and splenic marginal zone B cell lymphomas (MZBL) share morphological and immunophenotypic features with marginal zone B cells of reactive lymphoid tissues. Although displaying a similar immunophenotype, recent investigations suggest fundamental genetic differences among these subgroups. To determine the prevalence of the t(11;18) in a larger series of MALT-type lymphomas and to investigate a possible occurrence in other lymphomas, we screened 106 non-Hodgkin's lymphomas (NHL) by interphase cytogenetics using yeast artificial chromosome (YAC) probes flanking the breakpoint at 11q21. A signal constellation indicating a disruption in 11q21 and thus pointing to the presence of the t(11;18) was observed in 9 of 33 (27%) low-grade lymphomas of MALT type. The complete absence of t(11;18)-positive cells in 32 primary and secondary extranodal high-grade lymphomas suggests that low-grade lymphomas of MALT type characterized by the t(11;18) are unlikely to transform into high-grade tumors. The absence of tumor cells carrying the t(11;18) in nodal MZBL challenges the assumption that most, if not all, of these tumors represent the nodal manifestation of a so far undetected low-grade lymphoma of MALT type. The t(11;18) was not detected in a single case of 29 splenic MZBL investigated. This observation strengthens the view that splenic MZBL are biologically different from extranodal MZBL of MALT type.
Rosenwald
A
A
Pathologisches Institut, Universität Würzburg, Würzburg, Germany.
Ott
G
G
Stilgenbauer
S
S
Kalla
J
J
Bredt
M
M
Katzenberger
T
T
Greiner
A
A
Ott
M M
MM
Gawin
B
B
Döhner
H
H
Müller-Hermelink
H K
HK
D002871:Chromosome Banding; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000473:pathology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics / Q000473:pathology; D014178:Translocation, Genetic