A. Younes et al., CHROMOSOME-X NUMERICAL ABNORMALITIES IN PATIENTS WITH NON-HODGKINS-LYMPHOMA - A STUDY OF 59 PATIENTS USING FLUORESCENCE IN-SITU HYBRIDIZATION, Cancer genetics and cytogenetics, 82(1), 1995, pp. 23-29
Chromosome X numerical abnormalities are frequently observed in non-Ho
dgkin's lymphoma (NHL), with an incidence of 3% to 14% for chromosomal
loss and 7% to 33% for chromosomal gain. Because sex chromosome numer
ical abnormalities are thought to be due to aging, little information
is known about their relation to gender, therapy, and prognosis. There
fore, to determine the incidence and clinical relevance of this abnorm
ality in NHL, we studied specimens from 59 NHL patients (31 men and 28
women) by fluorescence in situ hybridization (FISH) using a directly
conjugated centromeric probe for chromosome X. The median age for the
entire group was 52 years (range, 31-88 years). All specimens were obt
ained by fine-needle aspiration of diseased lymph nodes. Sex-matched l
ymphocytes from benign hyperplastic lymph nodes were used as controls.
The overall incidence of chromosome X numerical abnormalities was 49.
2%. Female patients had a higher overall incidence than males (76% vs.
24%; p < 0.001). The median percentage of cells involved in this abno
rmality in each specimen was 5.2%. There was no statistically signific
ant difference in the incidence in previously treated than untreated p
atients (53.1% vs. 44.4%; p < 0.75) and in intermediate-grade NHL than
low-grade NHL (61.1% vs. 50%; p < 0.75). There was a trend towards a
higher incidence of chromosome X loss in older patients. While the dif
ference in the incidence of chromosome X abnormalities observed betwee
n women and men may be due to the difference in the normal copy number
s of this chromosome in each sex group, this abnormality remained high
er than any other autosomal chromosome abnormality in NHL previously e
valuated by FISH. We conclude that, although FISH detected a high inci
dence of chromosome X numerical abnormalities and that females had a h
igher incidence than males, only a small percentage of the cells were
involved, suggesting that this abnormality is most likely a secondary
genetic defect that is not important in the pathogenesis of NHL.