Table 3. Results of the most relevant studies using multiparameter flow cytometry for detection of minimal residual disease in multiple myeloma.
| Setting | Method | LOD | Number of patients | CR (%) | MRD-negativity (%) | PFS (MRD- vs MRD+) | P-value | OS (MRD- vs MRD+) | P-value | Reference |
|---|---|---|---|---|---|---|---|---|---|---|
| CT or ASCT | 4-color MFC | 10−4 | 87 | 39/87 (45%) | 23/87 (26%) | 60 m vs 34 m | 0.02 | NA | − | 48 |
| ASCT | 3-color MFC | 10−3–10−4 | 45 | 33/45 (73%) | 24/45 (56%) | 35 m vs 20 m | 0.03 | 76 vs 64% at 5-years | 0.28 | 49 |
| ASCT | 4-color MFC | 10−4 | 295 | 147/295 (50%) | 125/295 (42%) | 71 m vs 37 m | <0.001 | NR vs 89 m | 0.002 | 50 |
| Elderly | 4-color MFC | 10−4–10−5 | 102 | 44/102 (43%) | 24/102 (24%) | 90 vs 35% at 3-years | <0.001 | 94 vs 70% at 3-years | 0.08 | 90 |
| ASCT | 4-color MFC | 10−4–10−5 | 241, CR | 241 (100%) | 154/241 (64%) | 86 vs 58% at 3-years | <0.001 | 94 vs 80% at 3-years | 0.001 | 52 |
| ASCT | 6-color MFC | 10−4 | 397 | 214/394 (54%) | 246/394 (62%) | 29 m vs 14 m | <0.001 | 81 m vs 59 m | 0.02 | 51 |
| ASCT | 7-color MFC | 10−5 | 31 | 18/31 (58%) | 21/31 (68%) | 100 vs 30% at 3-years | NA | NA | − | 121 |
| R/R | 4-color MFC | 10−4 | 52, CR | 52 (100%) | 24/52 (46%) | 75 m vs 14 m | 0.03 | NA | − | 122 |
| Elderly | 4 & 8-color | 10−5 | 162 | 81/162 (50%) | 54/162 (34%) | Median TTP: MRD-ve: NR CR & MRD+ve: 20 m <CR & MRD+ve: 11 m | <0.001 | 3 year OS: MRD-ve: 67% CR & MRD+ve: 53% <CR & MRD+ve: 60% | 0.19 | 53 |
| NA | 4 & 6-color | 10−4 | 78, CR | 78 (100%) | 34/78 (44%) | 29.2 m vs 13.8 m | 0.009 | 110.7 m vs NR | 0.94 | 123 |
| Follow-up | NGF | 10−5 | 110 ⩾VGPR | 71/110 (64%) | convent. flow: 37/110 (34%) NGF: 52/110 (47%) | 75% NR vs 10 m | 0.01 | NA | − | 54 |
| RVD+SCT | ||||||||||
| RVD | 7-color MFC | 10−4 | 350 350 | 205/350 (59%) 169/350 (48%) | 220/278 (79%)a, 171/265 (65%)a | adjusted HR=0.30 | P<0.001 | adjusted HR=0.34 | P<0.001 | 124 |
Abbreviations: ASCT autologous stem cell transplantation; CR, complete remission; CT, Chemotherapy; HR, hazard ratio; m, month; MFC, multiparameter flow cytometry; MRD, minimal residual disease; NA, data not available; NGF, next-generation flow; OS, overall survival; PFS, progression-free survival; R/R, relapse/refractory; RVD, lenalidomide, bortezomib and dexamethasone; SCT, stem cell transplantation; VGPR, very good partial response.
a
MRD evaluated in patients reaching CR or VGPR.