The persistence of immunophenotypically normal residual bone marrow plasma cells at diagnosis identifies a good prognostic subgroup of symptomatic multiple myeloma patients

• Published in: Blood Vol. 114; no. 20; pp. 4369 - 4372
• Main Authors: Paiva, Bruno, Vidriales, Maria-Belén, Mateo, Gema, Pérez, Jose J., Montalbán, Maria Angeles, Sureda, Anna, Montejano, Laura, Gutiérrez, Norma C., García de Coca, Alfonso, de las Heras, Natalia, Mateos, Maria Victoria, López-Berges, Maria Consuelo, García-Boyero, Raimundo, Galende, Josefina, Hernández, Jose, Palomera, Luis, Carrera, Dolores, Martínez, Rafael, de la Rubia, Javier, Martín, Alejandro, González, Yolanda, Bladé, Joan, Lahuerta, Juan José, Orfao, Alberto, San-Miguel, Jesús F., on behalf of the GEM (Grupo Español de MM)/PETHEMA (Programa para el Estudio de la Terapéutica en Hemopatías Malignas) Cooperative Study Groups
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 12.11.2009; Americain Society of Hematology
• Subjects: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Biological and medical sciences; Bone Marrow Cells - pathology; Disease-Free Survival; Female; Flow Cytometry; Hematologic and hematopoietic diseases; Hematopoietic Stem Cell Transplantation; Humans; Immunodeficiencies. Immunoglobulinopathies; Immunoglobulinopathies; Immunopathology; Immunophenotyping; Kaplan-Meier Estimate; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Male; Medical sciences; Middle Aged; Multiple Myeloma - mortality; Multiple Myeloma - pathology; Multiple Myeloma - therapy; Plasma Cells - pathology; Prognosis; Human; Immunopathology; Prognosis; Hematology; Subgroup; Malignant hemopathy; Plasmocyte; Myeloma; Persistence; Immunoglobulinopathy; Lymphoproliferative syndrome; Bone marrow; Diagnosis; Cancer
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2009-05-221689

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.