Detecting residual disease in treated multiple myeloma patients at follow-up
The P2 assay is a high-sensitivity assay validated to a sensitivity of 0.01% (1 abnormal plasma cell/10,000 normal cells). This assay is NOT a minimal/measureable residual (MRD) assay, which requires a validated sensitivity of 0.001% (1/100,000). For follow-up of patients who are negative for residual abnormal plasma cells in the P2 assay, we recommend EDTA-anticoagulated bone marrow aspirate be submitted to the Mayo Clinic Laboratories for formal MRD testing (Mayo Clinic Laboratories test code: MRDMM).
Collect 3.0 mL (minimum 1.0mL) bone marrow aspirate in a sodium heparinized syringe and transfer to an anticoagulant free tube.
Complete the "Brief clinical information" and "What do you want answered by Flow?" areas on the Flow cytometry requisition
Ambient (preferred) - 72 hours
Frozen - NO
CD19, CD20, CD38, CD45, CD56, IRF4 (nuclear), Kappa (cytoplasmic), Lambda (cytoplasmic) and VS38 (cytoplasmic).