Response duration in all children who responded to rituximab (however transiently) and adults whose response lasted at least 1 year since treatment. Kaplan-Meier estimates of response to rituximab past 1 year in (A) children (n = 38) and (B) adults (n = 72). Vertical lines along the Kaplan-Meier curve indicate the last follow-up of an ongoing response. Adult long-term response rate projection originated at 1 year, 38%, based on published reports (Figure 1). Children's long-term response rate projection originated at 1 year, 33%, based on published reports and data presented in this study (gray line; Figure 1). Error bars (dotted lines) represent the 95% confidence intervals of response projections.