The clinical utility and prognostic value of multiparameter flow cytometry immunophenotyping in light-chain amyloidosis

• Published in: Blood Vol. 117; no. 13; pp. 3613 - 3616
• Main Authors: Paiva, Bruno, Vídriales, María-Belén, Pérez, José J., López-Berges, María-Consuelo, García-Sanz, Ramón, Ocio, Enrique M., de las Heras, Natalia, Cuello, Rebeca, de Coca, Alfonso García, Pardal, Emilia, Alonso, José, Sierra, Magdalena, Bárez, Abelardo, Hernández, José, Suárez, Lissbett, Galende, Josefina, Mateos, María-Victoria, San Miguel, Jesús F.
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 31.03.2011; Americain Society of Hematology
• Subjects: Adult; Aged; Aged, 80 and over; Amyloidosis - diagnosis; Amyloidosis - metabolism; Biological and medical sciences; Female; Flow Cytometry - methods; Heart Diseases - diagnosis; Heart Diseases - metabolism; Hematologic and hematopoietic diseases; Humans; Immunoglobulin Light Chains - metabolism; Immunophenotyping - methods; Kidney Diseases - diagnosis; Kidney Diseases - metabolism; Liver Diseases - diagnosis; Liver Diseases - metabolism; Male; Medical sciences; Middle Aged; Predictive Value of Tests; Prognosis; Flow cytometry; AL amyloidosis; Prognosis; Hematology; Immunophenotype
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2010-12-324665

The clinical value of multiparameter flow cytometry (MFC) immunophenotyping in primary or light chain amyloidosis (AL) remains unknown. We studied 44 consecutive bone marrow samples from newly diagnosed patients with amyloidosis; 35 patients with AL and 9 with other forms of amyloidosis. Monoclonal plasma cells (PCs) were identifiable by MFC immunophenotyping in 34 of 35 (97%) patients with AL, whereas it was absent from all but 1 of the 9 (11%) patients with other forms of amyloidosis. Quantification of bone marrow plasma cells (BMPCs) by MFC immunophenotyping was a significant prognostic factor for overall survival (OS) (≤ 1% vs > 1% BMPC cutoff; 2-year OS rates of 90% vs 44%, P = .02). Moreover, detecting persistent normal PCs at diagnosis identifies a subgroup of patients with AL with prolonged OS (> 5% vs ≤ 5% normal PC within all BMPC cutoff, 2-year rates of 88% vs 37%, P = .01). MFC immunophenotyping could be clinically useful for the demonstration of PC clonality in AL and for the prognostication of patients with AL.