S239: COMPARABLE LONG-TERM OUTCOMES BETWEEN UPFRONT HAPLOIDENTICAL AND IDENTICAL SIBLING DONOR HSCT IN APLASTIC ANEMIA: A NATIONAL REGISTRY-BASED STUDY

Abstract

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a curative option for severe aplastic anemia (SAA), and transplantation from identical sibling donors (ISDs) has been recommended as a first-line treatment. Aims: Haploidentical donor (HID) transplantation for SAA has made great advances; thus, an increased role of HID-SCT in SAA should be considered if an ISD is unavailable. Methods: We performed a national registry-based analysis comparing long-term outcomes in the upfront HID or upfront ISD SCT setting. Results: A total of 342 SAA patients were enrolled, with 183 patients receiving HID SCT and 159 receiving ISD SCT. The estimated 9-year overall survival (OS) and failure-free survival (FFS) were 87.1±2.5% and 89.3±3.7% (P = 0.173) and 86.5±2.6% vs. 88.1±3.8% (P = 0.257) for patients in the HID and ISD SCT groups, respectively. Transplantation from HID or ISD SCT has greatly improved quality of life (QoL) levels post-HSCT compared to pre-HSCT. The occurrence of chronic graft versus host disease was the only identified adverse factor affecting each subscale of QoL. Physical and mental component summaries in adults as well as physical, mental, social, and role well-being in children were all similar between HID and ISD SCT at 5-year points. At the last follow-up, the proportion of returning to society was comparable between the HID and ISD groups, showing 78.0% versus 84.6% among children and 74.6% versus 81.2% among adults. A total of 342 SAA patients were enrolled, with 183 patients receiving HID SCT and 159 receiving ISD SCT. The estimated 9-year overall survival (OS) and failure-free survival (FFS) were 87.1±2.5% and 89.3±3.7% (P = 0.173) and 86.5±2.6% vs. 88.1±3.8% (P = 0.257) for patients in the HID and ISD SCT groups, respectively. Transplantation from HID or ISD SCT has greatly improved quality of life (QoL) levels post-HSCT compared to pre-HSCT. The occurrence of chronic graft versus host disease was the only identified adverse factor affecting each subscale of QoL. Physical and mental component summaries in adults as well as physical, mental, social, and role well-being in children were all similar between HID and ISD SCT at 5-year points. At the last follow-up, the proportion of returning to society was comparable between the HID and ISD groups, showing 78.0% versus 84.6% among children and 74.6% versus 81.2% among adults. Image:Summary/Conclusion: These data suggest the recommendation for upfront transplantation with a haploidentical donor for SAA patients in the absence of an ISD, especially in experienced transplant centers.