BCL6-translocations affect the phenotype of follicular lymphomas only in the absence of t(14;18)IgH/BCL2.
BACKGROUND
The translocation t(14;18)IgH/BCL2 is the molecular hallmark of follicular lymphomas (FL). A subset of cases harbours translocations involving the BCL6-gene locus. This study aimed to determine the frequency of BCL2- and BCL6-translocations in FL and to identify morphological and immuno-histochemical features with respect to the presence of BCL2- and BCL6-translocations.


METHODS
Fluorescence-in-situ-hybridisation (FISH) was used to determine the BCL2- and BCL6-translocation status of 102 FL and these were compared to morphological and immunohistochemical parameters.


RESULTS
Lymphomas with BCL6- and BCL2-translocations were very similar to t(14;18)-positive lymphomas without BCL6-translocations. In contrast, t(14;18)-negative lymphomas with BCL6-translocations were amongst others of higher grade, less often CD10-positive, involved the bone marrow less frequently and did not infiltrate the lymph node capsule.


CONCLUSIONS
BCL2- and BCL6-translocations correlate with particular phenotypes of follicular lymphomas. BCL6-translocations seem to affect the phenotype only when they are not accompanied by BCL2-translocations.
Gollub
Wiebke
W
Department of Pathology, University Clinic Schleswig-Holstein, Campus Luebeck, Ratzeburger Allee 160, D-23538 Luebeck, Germany.
Stassek
Björn
B
Huckhagel
Torge
T
Bernd
Heinz-Wolfram
HW
Krokowski
Manuela
M
Merz
Hartmut
H
Feller
Alfred Christian
AC
Thorns
Christoph
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D004268:DNA-Binding Proteins / Q000235:genetics*; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008224:Lymphoma, Follicular / Q000235:genetics* / Q000469:parasitology; D008875:Middle Aged; D010641:Phenotype; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D051560:Proto-Oncogene Proteins c-bcl-6; D014178:Translocation, Genetic
C084103:BCL6 protein, human; D004268:DNA-Binding Proteins; D007143:Immunoglobulin Heavy Chains; D019253:Proto-Oncogene Proteins c-bcl-2; D051560:Proto-Oncogene Proteins c-bcl-6