Performance of the 42-probe-set (38-gene) gene expression classifier for prediction of RFS. (A-B) Kaplan-Meier survival estimates of RFS in the full cohort of 207 patients (A) and in the low- versus high-risk groups distinguished with the gene expression classifier for RFS (B). HR is the hazard ratio estimated using Cox regression. (C) A gene expression heatmap is shown with the rows representing the 42 probe sets (containing 38 unique genes) composing the gene expression classifier for RFS. The columns represent patient samples sorted from left to right by time to relapse or last follow-up. Red indicates high expression relative to the mean; green, low expression relative to the mean; R, relapse; and C, continuous remission.