Table 3.
MV Cox proportional hazards analysis of risk factors of progression to clinical MM requiring therapy
| Variable | n/N (%) | HR (95% CI) | P value | Cumulative R2 | |
|---|---|---|---|---|---|
| Clinical Variables | |||||
| Serum M-protein ≥3 g/dL* | 32/297 (11%) | 3.52 (1.86, 6.65) | <.001 | 22.23 | |
| Bone marrow PCs ≥20%* | 78/297 (26%) | 3.22 (1.77, 5.84) | <.001 | 40.65 | |
| Age ≥65 y | 127/297 (43%) | 2.10 (1.19, 3.69) | .010 | 46.14 | |
| Clincal + GEP variables | |||||
| GEP 70-gene risk >−0.26* | 32/117 (27%) | 6.81 (2.90, 15.97) | <.001 | 39.94 | |
| Serum M-protein ≥3 g/dL* | 17/117 (15%) | 6.49 (2.78, 15.18) | .006 | 63.12 | |
| Involved SFLC >25 mg/dL* | 27/117 (23%) | 3.15 (1.40, 7.08) | <.001 | 70.01 |
P value from Wald χ2 test in Cox regression. MV model uses stepwise selection with entry level 0.1 and variable remains if meet the 0.05 level.
Variables considered for clinical model: age ≥65, female, hemoglobin <12 g/dL, albumin <4 g/dL, serum B2M >3 mg/L, bone marrow PCs ≥20%, M-protein ≥3 g/dL, and uninvolved immunoglobulins low (<600 mg/dL if IgG, <50 mg/dL if IgM, <100 mg/dL if IgA).
Variables considered for clinical + GEP model: age ≥65, female, hemoglobin <12 g/dL, albumin <4 g/dL, serum B2M >3 mg/L, bone marrow PCs ≥20%, M-protein ≥3 g/dL, uninvolved immunoglobulins low (<600 mg/dL if IgG, <50 mg/dL if IgM, <100 mg/dL if IgA), and involved SFLC >25 mg/dL, involved/uninvolved (SFLC ratio >10, GEP 70-gene risk >−0.26, GEP poly-PC >11.60, GEP PR subgroup).
Optimal cut-points based on approximate running log-rank test statistic.