Relating 70 gene model-defined high risk with molecular features. (A) Scatterplot of gene expression–based proliferation index (x-axis) by 70-gene risk score in 351 patients of the training cohort. Low-risk patients (blue) and high-risk patients (red) defined by the 70-gene model are indicated. The 2 variables show a substantial degree of correlation (r = 0.73; P < .001). To evaluate the influence of the 2 variables on outcome, we divided the population into 4 subgroups using a PI cut-point of 5 and a high-risk cut-point of .66. The groups are defined by the intersection of the 2 green dotted lines. The top left quadrant contains patients with high PI/low risk, the top right quadrant contains patients with high PI/high risk, the bottom left quadrant contains patients with low PI/low risk, and the bottom right quadrant contains patients with low PI/high risk. The line represents the linear trend in the data. (B) Kaplan-Meier plots of overall survival estimates of the 4 groups defined in panel A, revealing no impact of PI within risk groups. (C) Kaplan-Meier plots of overall survival estimates of t(4;14)-positive myeloma in relationship to the 70-gene high-risk score designation of the given sample, showing the profound impact of high- and low-risk scores.