GAIN OF CHROMOSOME-7 MARKS THE PROGRESSION FROM INDOLENT TO AGGRESSIVE FOLLICLE CENTER LYMPHOMA AND IS A COMMON FINDING IN PATIENTS WITH DIFFUSE LARGE B-CELL LYMPHOMA - A STUDY BY FISH
P. Bernell et al., GAIN OF CHROMOSOME-7 MARKS THE PROGRESSION FROM INDOLENT TO AGGRESSIVE FOLLICLE CENTER LYMPHOMA AND IS A COMMON FINDING IN PATIENTS WITH DIFFUSE LARGE B-CELL LYMPHOMA - A STUDY BY FISH, British Journal of Haematology, 101(3), 1998, pp. 487-491
Gain of chromosome 7 represents one of the most frequent cytogenetic f
indings in B-cell lymphomas with a follicular growth pattern, We used
fluorescence in situ hybridization (FISH) and a probe specifying chrom
osome 7 on lymph node imprints and/or bone marrow (BM and peripheral b
lood (PB) smears from six consecutive patients with follicle centre ly
mphomas (FCLs) grade I or II (low-grade lymphomas), four patients with
FCLs grade III and 11 patients with diffuse large B-cell lymphomas (D
LBCLs) thigh-grade lymphomas). We found gains of chromosome 7 in 14/18
successfully analysed cases (i.e. 2/6 FCLs grade I-II, 3/3 FLCs grade
III and in 9/9 DLBCLs) using lymph node imprints. Moreover, the FISH
technique demonstrated gains of chromosome 7 in 1/4 BM and 0/4 PB samp
les from FCLs grade I-II, in 2/4 BM and 2/4 PB specimens from FCLs gra
de III and in 4/9 BM and 219 PB samples from the DLBCLs. In contrast,
morphologically recognizable lymphoma cells were seen in only 1/4 BM a
nd 0/4 PB samples from the FCLs grade III and in 1/11 BM and 1/11 PB s
amples from the DLBCLs. We conclude that: (i) gain of chromosome 7 mar
ks the progression from indolent to aggressive FCL and would appear to
be a common finding in patients with FCLs grade III and in DLBCLs, (i
i) clonal lymphoid cells occur frequently in BM and PB in high-grade l
ymphomas, making traditional staging by cytomorphology uncertain, and
(iii) using gains of chromosome 7 as a marker of lymphoma cells, FISH
is a useful method to detect minimal residual disease in FCLs grade II
I and DLBCLs.