Combining PET-CT and Bone Marrow Assessment in Multiple Myeloma
Posted: Monday, July 29, 2019
For patients with multiple myeloma, positron-emission tomography–computed tomography (PET-CT) and multiparameter flow cytometry are both well-established methods to determine the extent of disease and may be used in conjunction to identify subgroups of patients with different prognoses. Joaquín Martínez-López, MD, PhD, of the University of Madrid, Spain, and colleagues published their retrospective study in the American Journal of Hematology. Juan José Lahuerta, MD, and Dr. Martínez-López are joint senior authors of this study.
“These findings support the potential complementarity between PET-CT and [multiparameter flow cytometry] and highlight their better predictive capability when improving sensitivity…. Achieving double negativity by both techniques may become an aim, with impact on survival for any treatment,” concluded the authors.
In total, 103 patients with newly diagnosed multiple myeloma between 2008 and 2018 from 4 different Spanish hospitals were the study focus. The team assessed the prediction of outcome via the combination of PET-CT and achievement of minimal residual disease (MRD). Among the patients in the study, 65.1% became MRD-negative by multiparameter flow cytometry, and 70% with positive PET-CT results became PET-CT–negative by the time of follow-up. Patients achieving negative MRD status had a progression-free survival of 78 months compared with 45 months for those who remained MRD-positive. For patients who remained PET-CT–positive, the median progression-free survival was 27 months compared with 78 months for those who became PET-CT–negative at follow-up.
When MRD and PET-CT were combined, 54.4% of patients tested negative on both tests, 27.2% had a positive MRD and negative PET-CT, 12.6% had a negative MRD and a positive PET-CT, and 5.8% of patients tested positive on both tests. Patients who became MRD-negative on both tests had prolonged progression-free survival, 92 months, compared with those who remained MRD-positive or PET-CT–positive, 45 months and 28 months, respectively. There was a significant difference in 4-year overall survival rates between PET-CT–negative patients and PET-CT–positive patients, 94.2% to 100% compared with 73.8%.
Disclosure: The study authors reported no conflicts of interest.