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OCTOBER 16-18, 2011 • PORTLAND, OR
P33
Flow Cytometric Immunophenotypic Assessment
of T-cell Clonality in CSF and FNA Specimens
using Limited V Beta Repertoire Analysis
Prashant Tembhare, Constance Yuan, Armando Filie,
Maryalice Stetler-Stevenson
Laboratory of Pathology, National Cancer Institute,
NIH, Bethesda, MD, USA
Introduction: Flow cytometric (FC) TCR-Vβ repertoire
analysis (TCR-Vβ-R) is a sensitive method to detect
T-cell clonality; however, its implementation in low
cellularity specimens has not been established.
We developed a strategy to utilize TCR-Vβ-R in
cerebrospinal fuid (CSF) and fne needle aspirate
(FNA) specimens. Method: Comprehensive FC panel
with complete TCR-Vβ-R was used for initial FC
evaluation in diagnostic screening specimens from
10 patients with T-cell neoplasia to determine tumor
specifc TCR-Vβ protein expression. Abbreviated,
patient specifc TCR-Vβ-R evaluation was performed
in 21 subsequent paucicellular specimens (12 CSF, 9
FNA) using a single cocktail containing three anti-
Vβ antibodies (one tumor specifc and two negative
controls) in combination with other antibodies chosen
to help gate on atypical T-cells. The results of fow
cytometry were correlated with cytomorphological
results. Results: TCR-Vβ-R demonstrated T-cell
clonality in all initial screening peripheral blood (PB)
specimens from ten patients. Clonal T-cells were
detected in all FNA specimens and in nine of the 12
CSF specimens. The percent of lymphoid cells that
were clonal T cells ranged from 1.75 to 85% in FNA
specimens and from 1.4 to 100% in CSF specimens.
Conclusions: The Vβ-specifc-single-cocktail TCR-
Vβ-R strategy is highly sensitive and specifc in
evaluating T-cell clonality in precious low cellularity
specimens like CSF and FNA. This strategy can
be used to detect minimal involvement despite low
cellularity.
POSTER ABSTRACTS