Abstract

There are few treatment options for acute leukaemia children who relapse following hematopoietic cell transplantation (HCT). After undergoing a first HCT for relapse, 251 children and young adults with acute myelogenous or lymphoblastic leukaemia underwent a second HCT. The median time between the first and second HCTs was 17 months, and the median age at the second HCT was 11. The majority of the patients underwent unrelated donor HCT, a myeloablative conditioning regimen, and were in remission. In patients in remission, the 2-year probability of leukaemia free survival (LFS) was 33% following transplantation, compared to 19% in patients not in remission (P =.02) after transplantation. 24% and 10%, respectively, were the corresponding 8-year probability (P =.003). The variation in relapse rates was brought on by Patients in remission had a relapse chance of 22% following transplant, whereas those in relapse had a relapse probability of 56%. The respective probabilities over an 8-year period were 49% and 64%. The results of prior studies are expanded upon by these data, which demonstrate that second transplantation is more likely to be beneficial for individuals who have a modest disease burden. After the second year following the second HCT, late relapse caused a 10% decrease in LFS. This contrasts with the initial HCT, when the majority of relapses happen within two years of the HCT.