Next Generation Flow for highly sensitive and standardized detection of minimal residual disease in multiple myeloma

Leukemia. 2017 Oct;31(10):2094-2103. doi: 10.1038/leu.2017.29. Epub 2017 Jan 20.

Abstract

Flow cytometry has become a highly valuable method to monitor minimal residual disease (MRD) and evaluate the depth of complete response (CR) in bone marrow (BM) of multiple myeloma (MM) after therapy. However, current flow-MRD has lower sensitivity than molecular methods and lacks standardization. Here we report on a novel next generation flow (NGF) approach for highly sensitive and standardized MRD detection in MM. An optimized 2-tube 8-color antibody panel was constructed in five cycles of design-evaluation-redesign. In addition, a bulk-lysis procedure was established for acquisition of ⩾107 cells/sample, and novel software tools were constructed for automatic plasma cell gating. Multicenter evaluation of 110 follow-up BM from MM patients in very good partial response (VGPR) or CR showed a higher sensitivity for NGF-MRD vs conventional 8-color flow-MRD -MRD-positive rate of 47 vs 34% (P=0.003)-. Thus, 25% of patients classified as MRD-negative by conventional 8-color flow were MRD-positive by NGF, translating into a significantly longer progression-free survival for MRD-negative vs MRD-positive CR patients by NGF (75% progression-free survival not reached vs 7 months; P=0.02). This study establishes EuroFlow-based NGF as a highly sensitive, fully standardized approach for MRD detection in MM which overcomes the major limitations of conventional flow-MRD methods and is ready for implementation in routine diagnostics.

Publication types

  • Validation Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibody Specificity
  • Cell Count
  • Equipment Design
  • Female
  • Flow Cytometry / instrumentation
  • Flow Cytometry / methods*
  • Humans
  • Immunophenotyping / instrumentation
  • Immunophenotyping / methods*
  • Male
  • Middle Aged
  • Multiple Myeloma / diagnosis*
  • Multiple Myeloma / drug therapy
  • Multiple Myeloma / pathology
  • Neoplasm, Residual
  • Plasma Cells / pathology*
  • Sensitivity and Specificity
  • Software
  • Specimen Handling
  • Treatment Outcome