Pérez-Escurza, OihaneFlores-Montero, JuanÓskarsson, Jón ÞórirSanoja-Flores, Luzalbadel Pozo, JulioLecrevisse, QuentinMartín, SilviaReed, Elín RuthHákonardóttir, Guðlaug KatrínHarding, StephenÞorsteinsdóttir, SigrúnRögnvaldsson, SæmundurLöve, Þorvarður JónDurie, BrianKristinsson, Sigurður YngviOrfao, Alberto2025-11-202025-11-202023-12-11Pérez-Escurza, O, Flores-Montero, J, Óskarsson, J Þ, Sanoja-Flores, L, del Pozo, J, Lecrevisse, Q, Martín, S, Reed, E R, Hákonardóttir, G K, Harding, S, Þorsteinsdóttir, S, Rögnvaldsson, S, Löve, Þ J, Durie, B, Kristinsson, S Y & Orfao, A 2023, 'Immunophenotypic assessment of clonal plasma cells and B-cells in bone marrow and blood in the diagnostic classification of early stage monoclonal gammopathies : an iSTOPMM study', Blood Cancer Journal, vol. 13, no. 1, 182, pp. 182. https://doi.org/10.1038/s41408-023-00944-12044-538521424226213d012f1-f85f-475b-a99a-99f5e1f191c48517817681538072838unpaywall: 10.1038/s41408-023-00944-1https://hdl.handle.net/20.500.11815/7398Publisher Copyright: © 2023, The Author(s).Monoclonal gammopathy of undetermined significance (MGUS) is the earliest discernible stage of multiple myeloma (MM) and Waldenström’s macroglobulinemia (WM). Early diagnosis of MG may be compromised by the low-level infiltration, undetectable to low-sensitive methodologies. Here, we investigated the prevalence and immunophenotypic profile of clonal (c) plasma cells (PC) and/or cB-lymphocytes in bone marrow (BM) and blood of subjects with a serum M-component from the iSTOPMM program, using high-sensitive next-generation flow cytometry (NGF), and its utility in the diagnostic classification of early-stage MG. We studied 164 paired BM and blood samples from 82 subjects, focusing the analysis on: 55 MGUS, 12 smoldering MM (SMM) and 8 smoldering WM (SWM). cPC were detected in 84% of the BM samples and cB-lymphocytes in 45%, coexisting in 39% of cases. In 29% of patients, the phenotypic features of cPC and/or cB-lymphocytes allowed a more accurate disease classification, including: 19/55 (35%) MGUS, 1/12 (8%) SMM and 2/8 (25%) SWM. Blood samples were informative in 49% of the BM-positive cases. We demonstrated the utility of NGF for a more accurate diagnostic classification of early-stage MG.2138626182eninfo:eu-repo/semantics/openAccessB-LymphocytesBone MarrowHumansMonoclonal Gammopathy of Undetermined SignificanceMultiple Myeloma/diagnosisParaproteinemias/diagnosisPlasma CellsSmoldering Multiple Myeloma/complicationsWaldenstrom Macroglobulinemia/dk/atira/pure/researchoutput/researchoutputtypes/contributiontojournal/article10.1038/s41408-023-00944-1