Scientific publications
Mass spectrometry vs immunofixation for treatment monitoring in multiple myeloma
Noemi Puig 1 , Teresa Contreras Sanfeliciano 1 , Cristina Agullo Roca 2 , Joaquin Martinez-Lopez 3 , Albert Oriol 4 , María-Jesús Blanchard 5 , Rafael Rios-Tamayo 6 , Jesús Martín Sánchez 7 , M Belén Iñigo 8 , Anna Sureda 9 , Miguel-Teodoro T Hernandez Garcia 10 , Javier de la Rubia 11 , Veronica Gonzalez-Calle 12 , Isabel Krsnik 13 , Valentin Cabañas 14 , Luis Palomera 15 , Jose M Moraleda 16 , Joan Bargay 17 , María-Teresa Cedena 18 , Bruno Paiva 19 , Laura Rosiñol 20 , Joan Bladé 21 , Jesus F San-Miguel 22 , Juan-Jose Lahuerta 23 , Maria-Victoria Mateos 24
Abstract
Monitoring of the monoclonal protein (M-protein) by electrophoresis and/or immunofixation (IFE) has long been used to assess treatment response in multiple myeloma (MM).
However, with the use of highly effective therapies, the M-protein becomes frequently undetectable and more sensitive methods had to be explored. We applied IFE and mass spectrometry (EXENT&FLC-MS) in serum samples from newly diagnosed MM patients enrolled in the PETHEMA/GEM2012MENOS65 obtained at baseline (n=223), after induction (n=183), autologous stem cell transplantation (n=173) and consolidation (n=173).
At baseline, the isotypes identified with both methods fully matched in 82.1% of samples; in the rest but two samples, EXENT&FLC-MS provided additional information to IFE with regards to the M-protein/s. Overall, the results of EXENT&FLC-MS and IFE were concordant in >80% of cases, being most discordances due to EXENT&FLC-MS positive but IFE negative cases. After consolidation, IFE was not able to discriminate two cohorts with different median progression free survival (mPFS) but EXENT&FLC-MS did so; further, among IFE negative patients, EXENT&FLC-MS identified two groups with significantly different mPFS (p=0.0008).
In conclusion, compared to IFE, EXENT&FLC-MS is more sensitive to detect the M-protein of patients with MM, both at baseline and during treatment, and provides a more accurate prediction of patients´ outcome. This trial is registered at www.clinicaltrials.gov as NCT01916252.
CITATION Blood Adv. 2022 Jun 14;6(11):3234-3239.
doi: 10.1182/bloodadvances.2021006762.