IMMUNOGLOBULIN FREE LIGHT CHAINS – BIOCHEMICAL MARKERS OF MONOCLONAL GAMMOPATHIES

Serum κ- and λ- free light chains and their ratio were measured in 126 patients (23-80 years old) with monoclonal gammopathies and
60 normal individuals (25-82 years old). The free light chains (FLCs) assay was performed using the FreeliteTM test-system (The Binding
Site Ltd, UK) on the biochemical analyzer Hitachi 911. Serum FLCs (sFLCs) levels were found to be high in most patients with MM, Bence
Jones myeloma and plasmacytoma. The diagnostic accuracy of FLC assay in serum by immunoturbidimetry method was 90,5%. Combining
sFLCs testing with serum protein electrophoresis and immunofixation provides 98,8% accuracy in the first-line diagnosis of monoclonal
gammopathies. Our study demonstrated high diagnostic sensitivity and specificity for immunoturbidimetry method detection of FLC in serum
of patients with monoclonal gammopathies.

N.V. Lyubimova, T.Yu. Kharitidy, A.N. Danilov, O.M. Votyakova
Federal State Budgetary Institution «The N.N. Blokhin Russian Cancer Research Center» of the Russian Academy of Medical Sciences, Moscow, Russian Federation