The immunophenotypic stability of plasma cell myeloma by flow cytometry

M. D. Spears, H. Olteanu, S. H. Kroft, A. M. Harrington

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

Introduction: Flow cytometry (FC) has become increasingly utilized in the diagnosis and monitoring of plasma cell myeloma (PCM), though few studies have evaluated the longitudinal stability of antigen expression. Methods: We studied 45 PCM patients by four-color FC for shifts in CD19, CD20, CD38, CD45, CD56, and cytoplasmic light chain expression, between diagnostic/first encounter and positive follow-up analyses. An immunophenotypic (IP) change was defined as gain, loss, or 1/2 log shift of antigen expression. Results: An IP change was observed in 14/45 (31%) patients, with single IP changes in 9/14, two changes in 2/14, and three changes in 3/14. 3/14 reverted from an aberrant to a normal plasma cell IP, while remaining light chain-restricted. Changes in expression of CD45 occurred in 9/45 (20%), CD19 in 5/45 (11.1%), CD20 in 2/45 (4.4%), and CD56 in 5/45 (11.1%). Conclusion: Approximately 1/3 of PCM cases show IP changes over time, with CD45 the least stable antigen. Recognition of this relative instability is important to avoid narrow targeting of follow-up FC analyses, especially for minimal residual disease monitoring.

Original languageEnglish (US)
Pages (from-to)483-491
Number of pages9
JournalInternational Journal of Laboratory Hematology
Volume33
Issue number5
DOIs
StatePublished - Oct 1 2011

    Fingerprint

Keywords

  • Flow cytometry
  • Immunophenotype
  • Minimal residual disease
  • Plasma cell myeloma
  • Stability

ASJC Scopus subject areas

  • Hematology
  • Clinical Biochemistry
  • Biochemistry, medical

Cite this