The diagnostic value of kappa/lambda ratios determined by flow cytometric analysis of biopsy specimens in B-cell lymphoma.

Flow cytometry (FC) is widely utilized in the diagnosis of lymphoma and the light chain ratio (LCR) is especially useful in the diagnosis of B-cell malignancy. In this study we analysed, retrospectively, the predictive value of the LCR in the diagnosis of B-cell lymphoma in 105 consecutive patients with persistent lymph node enlargement or extranodal masses who underwent biopsy. We used a receiver-operating characteristic curve to establish a LCR threshold value of 2.0. The specificity, sensitivity, positive and negative predictive values were 92.3%, 73.1%, 90% and 77%, respectively. We concluded that determination of LCR is a useful adjunct to pathological diagnosis.