Prognosis of relapse after hematopoietic cell transplant (HCT) for treatment of leukemia or myelodysplastic syndrome (MDS) in children

Abstract

We studied 232 consecutive children transplanted between 1990 and 2011 with relapse after first hematopoietic cell transplant (HCT). Kaplan-Meier survival and hazard ratios for mortality were calculated for factors known at time of relapse using Cox proportional hazards models. The median (range) age at time of first HCT was 10.9 (0.5-20.9) years, time to relapse was 6.1 (0.2-89.5) months after HCT, and age at relapse was 11.7 (0.7-23.6) years. The 3-year overall survival (OS) after relapse was 13% (95% confidence interval (CI): 9%, 18%).The median (range) follow-up for the 18 surviving patients was 7.2 (3.0-24.4) years after relapse. The remaining 214 died after a median of 3 months (0.02-190.4). OS was not significantly different for patients with ALL as compared to AML. Fifty-one patients proceeded to second transplant of whom nine survive. Factors associated with improved survival included late relapse (>12 months), ALL in first CR at the time of first transplant and chemotherapy-based first conditioning regimens. These results can be used to counsel patients at the time of relapse after first transplant and as a baseline for comparison as to the effectiveness of newer therapies which are greatly needed for treatment of post-transplant relapse.

Figure 1.

Probability of overall survival for 232 patients after relapse of leukemia following allogeneic hematopoietic cell transplant (HCT). 95% confidence interval band is shaded.

Figure 2. Post-relapse treatment plan and outcomes.

Patients with relapse after 1^st transplant are grouped by disease (acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)). Arrows represent different treatment choices with the number (N) of patients receiving selected treatment. The first column to the right of arrows indicates patients who went onto second transplant for a given treatment plan reflected as # survivors/total # patients proceeding to 2^nd transplant. The final column on the right indicates patients who did not elect to proceed to 2^nd transplant reflected as # survivors/total # patients who did not proceed to 2^nd transplant. * Single patient with cytogenetic relapse and subsequent spontaneous resolution

Figure 3.

Probability of overall survival according after relapse following first allogeneic HCT by time from HCT to relapse (panel A, p<0.0001) or disease phase at time of HCT (panel, p=0.0078).