When the outcome variable of interest is an event that occurs some time after the test is measured, ROC curves must be time dependent. Two approaches have been proposed by Patrick Heagerty and colleagues. Software and documentation can be obtained here. Alternative approaches have been described in the literature.
Heagerty PJ and Zheng Y (2005). Survival model predictive accuracy an dROC curves. Biometrics 61:92-105.
Heagerty PJ, Lumley T and Pepe MS (2000) Time dependent ROC curves for censored survival data and diagnostic markers. Biometrics 56:337-344.