Overall survival and event-free survival of patients treated with R-HDS versus conventional chemotherapy. The Kaplan-Meier estimate of the percentage of patients alive or event-free at 54 months was 89% (95% confidence intervals [CI], 78% to 100%) and 79% (95% CI, 58% to 100%). For the 35 historic control patients, 54-month OS rate was 42% (95% CI, 24% to 59%) and the 54-month EFS was 18% (95% CI, 5% to 31%). There was a significant advantage for the R-HDS–treated patients in terms of both EFS (P < .0001) and OS (P = .027).