Concepedia

Minimal residual disease in myeloma by flow cytometry: independent prediction of survival benefit per log reduction

Andy C. Rawstron, Walter M. Gregory, Ruth M. de Tute, Faith E. Davies, Sue Bell, Mark T. Drayson, Gordon Cook, Graham Jackson, Gareth J. Morgan, J. A. Child,

Blood · 2015 · 182 citations · 9 references

DOI

Concepts

MedicineHematologyOncologyHematologic OncologyHematopathologyBone Marrow EvaluationFlow CytometryHematologic MalignanciesHematologic PathologyHematopoietic NeoplasmsMinimal Residual DiseaseFlow Cytometric Residual Disease AssessmentFlow Cytometry ImmunophenotypingLog Reduction ValueMinimal Residual Disease DetectionMinimal Residual Disease KineticsMinimal Residual Disease MarkersMinimal Residual Disease StratificationSurvival Benefit Assessment

Abstract

The detection of minimal residual disease (MRD) in myeloma using a 0.01% threshold (10(-4)) after treatment is an independent predictor of progression-free survival (PFS), but not always of overall survival (OS). However, MRD level is a continuous variable, and the predictive value of the depth of tumor depletion was evaluated in 397 patients treated intensively in the Medical Research Council Myeloma IX study. There was a significant improvement in OS for each log depletion in MRD level (median OS was 1 year for ≥10%, 4 years for 1% to <10%, 5.9 years for 0.1% to <1%, 6.8 years for 0.01% to <0.1%, and more than 7.5 years for <0.01% MRD). MRD level as a continuous variable determined by flow cytometry independently predicts both PFS and OS, with approximately 1 year median OS benefit per log depletion. The trial was registered at www.isrctn.com as #68454111.