DETECTION OF CLONAL EXCESS IN LYMPHOPROLIFERATIVE DISEASE BY KAPPA-LAMBDA ANALYSIS - CORRELATION WITH IMMUNOGLOBULIN GENE DNA REARRANGEMENT

  • 1 January 1986
    • journal article
    • research article
    • Vol. 67  (1) , 80-85
Abstract
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 "K/.lambda." analysis are indeed monoclonal. In > 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 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 K/.lambda. analysis, with one notable exception, that of detection of a monoclonal proliferation of B cells that did not express surface immunoglobulin. The K/.lambda. test thus offers a powerful diagnostic tool in the evaluation of lymphoproliferative disease.