Fine-needle aspiration (FNA) of lymph nodes is commonly used to assess disease progression in patients with small lymphocytic lymphoma (SLL). Although cytologic features are helpful for diagnosing typical SLL and transformed large-cell lymphoma (tLCL), SLL in accelerated phase (SLLacc) is more difficult to diagnose. Additional tests are needed to identify those patients who are transforming to a higher-grade lymphoma. This study evaluated the use of a multicolor fluorescence in situ hybridization (FISH) probe panel specifically designed for chronic lymphocytic leukemia (CLL)/SLL and assessed the association between FISH findings and cytologic diagnosis, proliferation index, and risk of death.
FNA specimens from 50 patients (32 men and 18 women; mean age, 57 years [range, 36-77 years]) with histologically confirmed CLL and/or SLL were evaluated in this study for chromosomal abnormalities of 11q22 (ATM), 12, 13q14.3, 13q34.3 (LAMP1), and 17p13.1 (p53) by using a multiprobe FISH kit. One of the 50 cases was excluded because of an insufficient number of cells for FISH analysis. The FISH findings were compared with the cytologic diagnoses (26 SLLs, 12 SLLaccs, and 11 tLCLs), Ki-67 immunostaining, and risk of death.
Abnormal signal patterns for 17p13.1 and 13q34.3 were associated with tLCL. Aberrations of 17p13.1 were found to be significantly associated with Ki-67 staining. Of the 49 patients with interpretable FISH results, 22 (45%) had died at the time of the study, with a mean overall survival time of 17 months after FNA. Patients with aberrations of 17p13.1 and 11q22 had 3.7 and 2.7 times the risk of death, respectively, compared with patients with normal patterns.
FISH can be performed on FNA specimens from patients with a history of SLL/CLL. Chromosomal aberrations of 17p13.1 and 11q22 are associated with an increased risk of death. Knowledge of genetic abnormalities from FNAs may be useful in deciding when and how to treat indolent or progressive SLL.