title: The persistence of immunophenotypically normal residual bone marrow plasma cells at diagnosis identifies a good prognostic subgroup of symptomatic multiple myeloma patients.
abstract: Multiparameter flow cytometry immunophenotyping allows discrimination between normal (N-) and myelomatous (MM-) plasma cells (PCs) within the bone marrow plasma cell compartment (BMPCs). Here we report on the prognostic relevance of detecting more than 5% residual normal plasma cells from all bone marrow plasma cells (N-PCs/BMPCs) by multiparameter flow cytometry in a series of 594 newly diagnosed symptomatic MM patients, uniformly treated according to the Grupo Español de MM 2000 (GEM2000) protocol. Our results show that symptomatic MM patients with more than 5% N-PCs/BMPCs (n = 80 of 594; 14%) have a favorable baseline clinical prospect, together with a significantly lower frequency of high-risk cytogenetic abnormalities and higher response rates. Moreover, this group of patients had a significantly longer progression-free survival (median, 54 vs 42 months, P = .001) and overall survival (median, not reached vs 89 months, P = .04) than patients with less than or equal to 5% N-PCs/BMPCs. Our findings support the clinical value of detecting residual normal PCs in MM patients at diagnosis because this reveals a good prognostic category that could benefit from specific therapeutic approaches. This trial was registered at www.clinicaltrials.gov as NCT00560053.
authors.affiliation: Hospital Universitario de Salamanca, Salamanca, Spain.
authors.forename: Bruno
authors.initials: B
authors.lastname: Paiva
authors.forename: Maria-Belén
authors.initials: MB
authors.lastname: Vidriales
authors.forename: Gema
authors.initials: G
authors.lastname: Mateo
authors.forename: Jose J
authors.initials: JJ
authors.lastname: Pérez
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Montalbán
authors.forename: Anna
authors.initials: A
authors.lastname: Sureda
authors.forename: Laura
authors.initials: L
authors.lastname: Montejano
authors.forename: Norma C
authors.initials: NC
authors.lastname: Gutiérrez
authors.forename: Alfonso
authors.initials: A
authors.lastname: García de Coca
authors.forename: Natalia
authors.initials: N
authors.lastname: de las Heras
authors.forename: Maria Victoria
authors.initials: MV
authors.lastname: Mateos
authors.forename: Maria Consuelo
authors.initials: MC
authors.lastname: López-Berges
authors.forename: Raimundo
authors.initials: R
authors.lastname: García-Boyero
authors.forename: Josefina
authors.initials: J
authors.lastname: Galende
authors.forename: Jose
authors.initials: J
authors.lastname: Hernández
authors.forename: Luis
authors.initials: L
authors.lastname: Palomera
authors.forename: Dolores
authors.initials: D
authors.lastname: Carrera
authors.forename: Rafael
authors.initials: R
authors.lastname: Martínez
authors.forename: Javier
authors.initials: J
authors.lastname: de la Rubia
authors.forename: Alejandro
authors.initials: A
authors.lastname: Martín
authors.forename: Yolanda
authors.initials: Y
authors.lastname: González
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; D000971:Antineoplastic Combined Chemotherapy Protocols; D001854:Bone Marrow Cells / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D005434:Flow Cytometry; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D016130:Immunophenotyping; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D010950:Plasma Cells / Q000473:pathology*; D011379:Prognosis