Numeric chromosomal abnormalities in small lymphocytic and transformed large cell lymphomas detected by fluorescence in situ hybridization of fine-needle aspiration biopsies.

BACKGROUND

Chromosomal abnormalities in some lymphomas are associated with a poor prognosis. Trisomy 12 and deletions of chromosome 13 have been described in small lymphocytic lymphoma (SLL). To determine whether chromosomal aberrations could be detected by fluorescence in situ hybridization (FISH) on fine-needle aspiration biopsies (FNABs), we analyzed and compared specimens from seven patients with SLL and nine patients with a history of SLL that had transformed to large cell lymphoma.

METHODS

DNA probes specific to chromosome 12 and the chromosome 13/RB-1 gene locus were used for in situ hybridization on interphase cell nuclei. The cytologic features, ploidy, proliferation index, and conventional cytogenetic analysis findings were correlated with the FISH results.

RESULTS

Trisomy 12 was detected in 2 (29%) of the 7 cases of SLL and 2 (22%) of the 9 cases of transformed large cell lymphoma. Deletion of chromosome 13/RB-1 was present in 3 (43%) of 7 cases of SLL and 3 (33%) of 9 cases of transformed large cell lymphoma.

CONCLUSIONS

This study showed that interphase cytogenetic analysis by FISH is feasible on FNAB specimens. Trisomy 12 and deletions of chromosome 13/RB-1 were present in some cases of SLL and transformed large cell lymphoma, and the presence of these chromosomal abnormalities did not correlate with transformation to a higher grade of lymphoma.