The utility of the serum heavy/light chain assay as a complementary tool in the monitoring of patients with plasma cell myeloma: a report of three cases.

We report three cases of plasma cell myeloma with obscure and discordant data for a monoclonal component. In this study, the results of serum heavy/light chain (sHLC) were retrospectively compared with those of conventional methods during disease monitoring. All three patients achieved a complete response and experienced a relapse during follow-up, and the sHLC ratio allowed early prediction of disease relapse and correlated well with other electrophoretic methods compared with the free light chain ratio. Therefore, we suggest that the sHLC assay may be useful as a complementary tool; it has a good correlation with conventional methods and sensitivity in assessing disease status and treatment response in patients with plasma cell myeloma.