Applications and limitations of peripheral blood lymphocyte immunoglobulin light chain analysis in the evaluation of XXXX .

@entity1 @entity3329 @entity66 @entity1778 @entity1893
Surface immunoglobulin (sIg) light chain analysis of peripheral blood lymphocytes (PBL) from 63 @entity1 with @entity1893 ( @entity1893 ) was performed to determine the ratio of kappa-bearing lymphocytes to lambda-bearing lymphocytes (kappa/lambda ratio). In 43% an abnormal kappa/lambda ratio was detected, implying the presence of a malignant clone in the peripheral blood (clonal excess). In 67% of cases with an abnormal kappa/lambda ratio, the absolute lymphocyte count was within normal limits and 20% did not have morphologic bone marrow involvement. Light chain analysis of bone marrow aspirates was performed in three of four @entity1 with a circulating clone and normal bone marrow morphology. All three @entity1 had abnormal bone marrow aspirate kappa/lambda ratios. The presence of a circulating clone was associated with morphologic bone marrow involvement (P less than 0.05). Nine @entity1 with documented B-cell @entity1893 were followed with repeated examinations. The presence of a circulating clone persisted in two @entity1 refractory to therapy and in two @entity1 otherwise believed to be in remission. Conversion to an abnormal kappa/lambda ratio occurred in two @entity1 coincident with the development of new bone marrow involvement and in a third @entity1 prior to the onset of @entity1778 . In three instances, the PBL light chain analyses remained within normal limits in @entity1 with stable @entity3329 . The kappa/lambda ratio returned to normal in one @entity1 responding to treatment with a partial remission, and remained within normal limits despite progression of @entity3329 in one @entity1 , and @entity66 recurrence in another @entity1 . These findings suggest that the detection of a circulating clone by sIg light chain analysis may be useful as a noninvasive approach to identify disseminated disease activity unsuspected on the basis of morphologic evaluations, but may not reflect the presence, progression, or recurrence of localized tissue lesions.
