Abstract
Transplantation of marrow from an unrelated donor offers the possibility of a cure for the 70 percent of patients with chronic myeloid leukemia (CML) who can tolerate the procedure and for whom a related donor is unavailable.1 The probability of finding an unrelated donor with HLA-A, B, and DR antigens that serologically match those of the recipient is about 80 percent within an 80-day period, thanks to the nearly 5 million volunteers enrolled in bone marrow–donor registries worldwide (Goldmann SS: personal communication). Despite these optimistic prospects, the actual results of treating CML with bone marrow from unrelated donors have been . . .