Validation of the 51-gene signature in four independent datasets.

<p>Kaplan-Meier survival analysis was performed in low (<i>full red line</i>) and high (<i>dashed blue line</i>) risk patient groups defined by the 51-gene classifier. AUC for survival models based on stage (<i>dashed red line</i>) or 51-gene classifier (<i>full black line</i>) was also compared. The testing dataset GSE8894 do not have available stage information and all patients in the WUSTL dataset are stage IB. So the time dependent ROC using stage information in these two datasets could not be calculated; all set at 0.5 instead. Tick marks, patients whose data were censored at last follow-up.