Utility of flow cytometric κ and λ light chain analysis of peripheral blood.

PURPOSE: Monoclonality in the peripheral blood can be shown by flow cytometric analysis of kappa (κ) and lambda (λ) light chain ratio of B lymphocytes. We aimed to show the utility of this method in patients with unknown causes of lymphadenopathy and/or splenomegaly.

METHODS

This method was performed in 81 adult patients with undefined causes of lymphadenopathy and splenomegaly.

RESULTS

18 (22%) of these patients had clonality and all of them were diagnosed as B cell lymphoma later. None of the patients with benign causes had clonality in the peripheral blood. We could not find any relationship between presence of clonality and type and stage of lymphoma and bone marrow involvement.

CONCLUSION

This method is easy to perform, cheap and non-invasive and yet it can give valuable information about the malignant nature of a suspected disease. If there is a sign of clonality in the peripheral blood, more invasive diagnostic procedures should be performed rather than watch and wait.