Detection of clonal excess in lymphoproliferative disease by kappa/lambda
analysis: correlation with immunoglobulin gene DNA rearrangement
N Berliner, KA Ault, P Martin and DS Weinberg
Previous studies have suggested that analysis of the distribution of
surface immunoglobulin light chain isotypes by flow cytometry provides
evidence for monoclonality of B cell tumors and may detect populations of
circulating tumor cells in patients with lymphoproliferative disease. We
have used simultaneous flow cytometry and DNA restriction enzyme analysis
on 58 samples of tissue and blood to determine whether lymphocyte
populations detected by "kappa/lambda" analysis are indeed monoclonal. In
greater than 90% of cases, abnormalities detected by flow cytometry
correlated with monoclonal rearrangements of immunoglobulin genes as
detected by Southern blot analysis. By analyzing tissue and blood from the
same patients, we have also demonstrated that monoclonal circulating cells
detected by flow cytometry reflect peripheral circulating tumor cells,
since DNA from these cells shows the same immunoglobulin rearrangement as
DNA from the original tumors in these patients. Although mixing studies
suggested that DNA rearrangement studies were more sensitive than was flow
cytometry in detecting minor populations of monoclonal lymphocytes, we
found only one case in which this affected the diagnostic accuracy of the
kappa/lambda analysis, with one notable exception, that of detection of a
monoclonal proliferation of B cells that did not express surface
immunoglobulin. The kappa/lambda test thus offers a powerful diagnostic
tool in the evaluation of lymphoproliferative disease.
Volume 67,
Issue 1,
pp. 80-85,
01/01/1986
Copyright © 1986 by The American Society of Hematology
