title: Multiparameter flow cytometry quantification of bone marrow plasma cells at diagnosis provides more prognostic information than morphological assessment in myeloma patients.
abstract: Quantification of bone marrow plasma cells in multiple myeloma patients using conventional morphology is of limited prognostic value, while the merit of multiparameter flow cytometry immunophenotyping is still considered unproven. Here we compare the bone marrow plasma cell counts obtained by morphology and multiparameter flow cytometry and explore the potential prognostic impact of both techniques in 765 newly diagnosed, uniformly treated multiple myeloma patients. Although multiparameter flow cytometry generally yields lower plasma cell counts (median percentage of 11% vs. 40%, respectively; p<0.001), there is a significant positive correlation between the two techniques (R =0.46, p<0.001). Regarding prognosis, multivariate analysis selected the bone marrow plasma cell counts obtained by multiparameter flow cytometry as an independent prognostic factor for overall survival (p=0.007), supporting the incorporation of multiparameter flow cytometry immunophenotyping into the routine diagnostic evaluation of multiple myeloma patients and validating the clinical utility of bone marrow plasma cell counting by multiparameter flow cytometry approaches. (clinicaltrials.gov identifier: NCT00560053).
authors.affiliation: Hospital Universitario de Salamanca, Paseo de San Vicente 58-182, 37007 Salamanca, Spain.
authors.forename: Bruno
authors.initials: B
authors.lastname: Paiva
authors.forename: Maria-Belén
authors.initials: MB
authors.lastname: Vidriales
authors.forename: Jose J
authors.initials: JJ
authors.lastname: Pérez
authors.forename: Gema
authors.initials: G
authors.lastname: Mateo
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Montalbán
authors.forename: Maria Victoria
authors.initials: MV
authors.lastname: Mateos
authors.forename: Joan
authors.initials: J
authors.lastname: Bladé
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Lahuerta
authors.forename: Alberto
authors.initials: A
authors.lastname: Orfao
authors.forename: Jesús F
authors.initials: JF
authors.lastname: San Miguel
mesh_terms: D000328:Adult; D000368:Aged; D001854:Bone Marrow Cells / Q000473:pathology; D002452:Cell Count; D019937:Diagnostic Techniques and Procedures; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis / Q000473:pathology*; D011379:Prognosis