Multicenter Retrospective Analysis of Second Allogeneic HSCT Outcomes for Hematologic Malignancies in Korea.

Increasing number of autologous or allogeneic HSCT in Korea in this decade resulted in increasing requirement for second allogeneic hematopoietic stem cell transplantation (HSCT) as a result of the recurrence of primary disease or graft failure. Since Dec 2008, second HSCT has been approved by Korean government to be covered by national health insurance reimbursement system. However, there is no available data on the transplant outcomes following second allogeneic HSCT in Korea. Accordingly, the current study attempted to analyze the outcome of second allogeneic HSCT retrospectively.

Transplant data were collected retrospectively from 8 transplant centers in Korea. Inclusion criteria are as follows. 1) Age equal or over 15 years old, 2) Hematologic malignancies excluding aplastic anemia, PRCA, PNH or solid tumor, 3) Patients who underwent second alloHSCT receiving cord blood transplantation (CBT).

Sixty four pts were included with following diagnoses: AML (n=28), ALL (n=5), CML (n=3), lymphoma (n=22), myeloma (n=5), and others (n=1). The median age was 37 (range 16-65). The first transplantation had been performed with autologous (59.4%) or allogeneic (40.6%) donors. The donors for second HSCT were HLA-identical sibling 32(47%), unrelated 28(49%), or haploidentical donor 2(4%). Conditioning regimen included TBI-based myeloablative 6(9%), non TBI myeloablative 19(30%), or reduced intensity regimen 38(60%). With median 16 months of follow up (range, 3 to 93 months), 40 pts died of transplant related toxicity (n=28; 70%), recurrence of primary disease (n=9; 22.5%) or other (n=3; 7.5%). After second HSCT, 56% were in complete remission, 38% in partial remission, and 6% were refractory. The 1- and 2- year overall survival rate was 42% and 29%, respectively.

The patients received non TBI conditioning regimens were shown longer survival.

No relevant conflicts of interest to declare.