Secondary chromosome changes in mantle cell lymphoma.
OBJECTIVE
Mantle cell lymphomas (MCLs) comprise a rare but distinct clinicopathological entity usually associated with t(11;14). This translocation is regarded as a primary event, but it has been suggested that other as yet unidentified genetic alterations are required for development and progression of MCL.


METHODS
In order to identify recurrent secondary changes that might point towards specific chromosomal regions contributing to the pathogenesis of MCL we studied 43 MCL cases in which clonal chromosomal abnormalities have been found during cytogenetic analysis.


RESULTS
In this series 83% of cases were characterized by t(11;14) and in the majority of them the t(11;14) was associated with multiple other chromosomal aberrations. Recurrent secondary changes were found in which imbalances of genetic material prevailed, losses being more common than gains. The former involved thirteen chromosomes, especially 13, 6q, 9q, 11q, 8/8p, 10/10p, and 14, whereas recurrent gains affected 3/3q. Non-randomly occurring breakpoints were relatively infrequent. The identified anomalies were also involved in aberrations observed in the group of MCL not associated with t(11;14). Some of them are shared with other B-cell proliferations.


CONCLUSIONS
The data presented here indicate that MCL is characterized by consistently occurring secondary chromosome changes. Their significance for the development and/or progression of MCL needs to be elucidated and confirmed by further investigations.
Centre for Human Genetics, Herestraat 49, B-3000 Leuven, Belgium.
I
I
Wlodarska
S
S
Pittaluga
A
A
Hagemeijer
C
C
De Wolf-Peeters
H
H
Van Den Berghe
D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D002880:Chromosomes, Human, Pair 11; D002883:Chromosomes, Human, Pair 14; D006801:Humans; D007621:Karyotyping; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics* / Q000473:pathology; D014178:Translocation, Genetic