Table 1. Characteristics of patients with symptomatic MM (N=53), grouped by MB4 breakpoints.
| Breakpoint | MB4-1 | MB4-2/MB4-3 | P |
|---|---|---|---|
| n (%) | 25 (47.2) | 28 (52.8) | |
| Gender (male, %) | 17 (68) | 17 (60.7) | 0.775 |
| Median age, years (range) | 59 (42-85) | 60 (49-74) | >0.05 |
| M isotype,n (%) | 0.305 | ||
| IgA | 11 (44) | 7 (25) | |
| IgG | 11 (44) | 18 (64.3) | |
| IgD | 0 (0) | 1 (3.57) | |
| Light chains, n (%) | 3 (12) | 2 (7.14) | |
| BM plasmacytosis≥50%, n (%) | 7 | 4 | 0.219 |
| Albumin (g/L) ≤ 35, n (%) | 13 (52) | 17 (60.7) | 0.586 |
| Calcemia ≥2.8 mmol/L, n (%) | 2 (8) | 3 (10.7) | 1 |
| Creatinine≥176 μmol/L, n (%) | 5 (20) | 8 (28.6) | 0.536 |
| Elevated lactate dehydrogenase, n (%) | 4 (16) | 10 (35.7) | 0.129 |
| Involved/uninvolved serum free light ratio≥100, n (%) | 6 (24) | 9 (32.1) | 0.556 |
| Anemia (g/L), n (%) | 0.969 | ||
| >100 | 7 (28) | 8 (28.6) | |
| 80~100 | 7 (28) | 7 (25) | |
| <80 | 11 (44) | 13 (46.4) | |
| Number of osteolytic destruction (≥3), n (%) | 19 (76) | 18 (64.3) | 0.387 |
| Extramedullary invasion, n (%) | 4 (16) | 8 (28.6) | 0.337 |
| DS, n (%) | 1 | ||
| I+II | 2 (8) | 2 (7.1) | |
| III | 23 (92) | 26 (92.9) | |
| R-ISS, n (%) | 0.237 | ||
| I+II | 20 (80) | 18 (64.3) | |
| III | 5 (20) | 10 (35.7) | |
| FGFR3 expression, n (%) | 22 (88) | 21 (75) | 0.302 |
| Cytogenetic abnormality | |||
| Del(13q) | 17 (68) | 23 (82.1) | 0.339 |
| Del(17p) | 5 (20) | 6 (21.4) | 1 |
| Amp(1q21) | 13 (52) | 19 (67.9) | 0.272 |
| High-risk [(any del(17p) or amp(1q21)] | 14 (56) | 21 (75) | 0.162 |
| Induction treatment, n=53 | |||
| Bortezomib-based regimen, n (%) | 19 (76) | 16 (57.1) | 0.148 |
| Immunomodulatory drug-based regimen, n (%) | 3 (12) | 8 (28.6) | 0.138 |
| Traditional chemotherapy, n (%) | 3 (12) | 4 (14.3) | 1 |
| High dose therapy + ASCT, n (%) | 4 (16) | 5 (17.9) | 1 |
| Response after 4 cycles induction therapy, n=53 | 0.54 | ||
| Partial response, n (%) | 4 (16) | 5 (17.9) | 1 |
| Very good partial response, n (%) | 10 (40) | 12 (42.9) | 1 |
| Complete response, n (%) | 8 (32) | 4 (14.3) | 0.19 |
| Stable disease, n (%) | 2 (8) | 3 (10.7) | 1 |
| Progressive disease, n (%) | 1 (4) | 4 (14.3) | 0.355 |
| Overall response, n (%) | 22 (88) | 21 (75) | 0.302 |
| CR after two cycles of induction therapy, n (%) | 5 (20) | 1 (3.6) | 0.089 |
| VGPR after two cycles of induction therapy, n (%) | 11 (44) | 11 (39.3) | 0.785 |
R-ISS: Revised International Staging System; Ig: immunoglobulin; BM: bone marrow.