Patient cohort and outcome after HCT. (A) Thirteen transplanted patients (magenta shades, 6 asymptomatic [diagnosed because of an affected sibling]; mean age, 14.4 years; range, 2-35 years) and 22 nontransplanted patients (blue shades; mean age, 6.5 years; range, 2-32 years). Four patients were referred from other European countries (Belgium, Denmark, and Luxemburg); the remainder came from The Netherlands. (B) Overall survival probability for transplanted and nontransplanted patients. (C) Probability of IFS and AFS for transplanted and nontransplanted patients. (D) Probability of IFS and AFS for symptomatic (n = 7) and presymptomatic (n = 6) transplanted patients.