Multivariate analysis of EFS and OS in the training cohort
| Significant predictors* . | % of cases . | EFS . | OS . | ||
|---|---|---|---|---|---|
| HR . | P . | HR . | P . | ||
| High-risk up-/down-regulated expression ratio (log2-scale)† | 13 | 3.24 | < .001 | 4.09 | < .001 |
| β2-microglobulin | |||||
| 297.5 nM to less than 467.5 nM | 20 | 1.72 | .001 | — | — |
| 467.5 nM or greater | 21 | 2.01 | — | — | |
| LDH, 190 IU/L or above | 34 | — | — | 1.92 | .004 |
| Interphase FISH, defined del13 | 33 | 1.63 | .007 | — | — |
| GEP-defined high-risk translocations | 18 | 1.97 | .001 | 1.85 | .012 |
| Significant predictors* . | % of cases . | EFS . | OS . | ||
|---|---|---|---|---|---|
| HR . | P . | HR . | P . | ||
| High-risk up-/down-regulated expression ratio (log2-scale)† | 13 | 3.24 | < .001 | 4.09 | < .001 |
| β2-microglobulin | |||||
| 297.5 nM to less than 467.5 nM | 20 | 1.72 | .001 | — | — |
| 467.5 nM or greater | 21 | 2.01 | — | — | |
| LDH, 190 IU/L or above | 34 | — | — | 1.92 | .004 |
| Interphase FISH, defined del13 | 33 | 1.63 | .007 | — | — |
| GEP-defined high-risk translocations | 18 | 1.97 | .001 | 1.85 | .012 |
N = 325; 26 of 351 patients were missing FISH-defined del13. MMSET/FGFR3 spikes (14.1%) are combined with MAF/MAFB spikes (3.7%). Low risk includes CCND1 spikes (16.9%) and no spike (65.3%). The collapsed categories perform better as prognostic categories due to the similarity in outcome distribution for the subgroups within high-risk and low-risk categories and the small size of the MAF/MAFB subgroup. For EFS, the number of events or deaths was 138; for OS, it was 87; the R2 values were 0.324 and 0.288, respectively.
—indicates insignificance for one or the other outcome.
Predictors with P >.05 for both outcomes: aged 65 years or older, metaphase cytogenetic abnormalities, albumin of 35 g/L or less, and C-reactive protein of 4 mg/L or more.
The average log2 (expression) of the 51 Q4 genes minus the average log2 (expression) of the 19 Q1 genes (ie, the log2 scale ratio of geometric mean up-regulated vs down-regulated genes). High risk by K-means clustering is 0.66 or greater (ie, a ratio of 1.58).