English 
Italian CONTRIBUTI SCIENTIFICI – Scientific Papers
Volume:
Biochimica Clinica 2013; 37(5) 383-388
Pubblicato on-line:
DOI:
Analisi combinata dei saggi Hevylite e Freelite nella valutazione precoce della recidiva di mieloma multiplo
AUTORI
1Divisione di Ematologia, Università di Torino, Azienda Ospedialiera Città della Salute e della Scienza di Torino, Presidio Molinette, Torino
2Ospedale e Casa di Cura dei Missionari della Consolata – Koelliker, Torino
3Bioci Produzione Diagnostici, Airasca, TO
ABSTRACT
Simultaneous evaluation of serum Hevylite and Freelite assays for relapse prediction in multiple myeloma
In multiple myeloma (MM), an accurate quantification of monoclonal immunoglobulin (M-Ig) and its variations during the course of the disease is important for prognosis, response evaluation and treatment selection. International guidelines recommend serum free light chain (sFLC) assays and free light chain ratio (sFLCr) for monoclonal gammopathy monitoring. Recently, a new immunoassay (Hevylite assay, sHLC), based on the analysis of k and l chains within intact immunoglobulins, has been developed. Similarly to sFLCr, a Hevylite assay ratio (sHLCr) can be determined. sHLC assay overcomes some technical limitations of sFLC assay, allows an accurate quantification of both the involved and uninvolved immunoglobulin in the tumour process and permits to quantify even very small monoclonal components. Aim of this work was to determine whether there is any additional advantage in predicting MM recurrence by sHLC compared to sFLC. A total of 208 serum samples, obtained from 37 MM patients from remission phase to relapse, were retrospectively analyzed by sFLC and sHLC assays; moreover, sFLCr and sHLCr results were compared in terms of relapse prediction. In 23 out of 37 patients (62%) sHLCr became abnormal before sFLCr and the median advantage of sHLCr vs. sFLCr in terms of time of relapse prediction was 3 months. Our analysis suggests that sHLCr is an earlier predictor of relapse than sFLCr. However, in a small group of MM cases, sFLCr became abnormal earlier than sHLCr. The combined use of sFLCr and sHLCr is, therefore, suggested to increase the predictive power of laboratory tests.