Partitioned Kaplan-Meier survival curves according to treatment group, ie, early HDT group (top plot) and late HDT group (bottom plot). Each plot displays the Kaplan-Meier estimations of time to OS, EFS, and time to end-of-treament, either conventional chemotherapy (CCT) or transplantation (HDT), since randomization. Note that two EFS were considered in the late HDT group (after conventional chemotherapy, “post-CCT” and after transplantation, “post-HDT”). The areas between these curves and the vertical line at 58 months, which corresponds to the median follow-up of the whole cohort, represent estimates of the mean durations between these events, namely treatment duration (either CCT [▧] or HDT [⊞]), time without symptoms and treatment toxicity (TWISTT [▧]), and time between relapse and death (▨). All patients were included in the analysis on an intent-to-treat basis. IFN was not taken into account because it was usually maintained only when well tolerated.