Overall survival. (A) Overall survival by age at transplantation The 5-year probabilities of overall survival for patients aged ≤6 years, 7 to 15 years, and 16 to 25 years were 90% (88% to 93%), 84% (80% to 87%), and 63% (45% to 82%), respectively. (B) Overall survival by donor type. The 5-year probabilities of overall survival after HLA-matched relative, HLA-mismatched relative, HLA-matched unrelated, and HLA-mismatched unrelated donor transplants were 89% (87% to 91%), 73% (64% to 82%), 87% (81% to 93%), and 83% (74% to 91%), respectively.