Table 4

Multivariate analysis of EFS and OS in the training cohort

Significant predictors*% of casesEFSOS
HRPHRP
High-risk up-/down-regulated expression ratio (log2-scale)133.24< .0014.09< .001
β2-microglobulin
    297.5 nM to less than 467.5 nM201.72.001
    467.5 nM or greater212.01
LDH, 190 IU/L or above341.92.004
Interphase FISH, defined del13331.63.007
GEP-defined high-risk translocations181.97.0011.85.012
  • 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).