Journal: Blood advances
Study type
- Retrospective analysis of 179 children with severe aplastic anemia undergoing allogeneic HSCT.
Cohorts
- Up-front HSCT: 87 patients.
- HSCT after failure of immunosuppressive therapy (IST): 92 patients.
Follow-up and key outcomes
- Median follow-up after HSCT: 4.0 years (range 0.2–10.7).
- Survival at last follow-up: 161/179 patients alive.
- Cumulative incidence:
- Graft failure: 10%
- Grade 2–4 acute GVHD: 18%
- Chronic GVHD: 8%
- Five-year outcomes for the entire cohort:
- Overall survival (OS): 89%
- GVHD-free, relapse/rejection-free survival (GRFS): 79%
Donor type and timing
- Up-front HSCT from either:
- Matched sibling donor (MSD)
- ≥9/10 HLA-matched unrelated donor (MUD)
- Overall survival (OS) for both up-front MSD and MUD HSCT: 95%.
Impact of prior IST
- OS was better with up-front HSCT vs HSCT after IST failure (overall timeframe):
- Up-front: 95% (95% CI, 89–100)
- After IST failure: 83% (95% CI, 75–91); P < .01
- From 2015 onward, outcomes for HSCT after IST failure improved:
- Up-front HSCT OS: 97%
- HSCT after IST failure OS: 89%; P = .09 (no longer significantly different)
- For MUD transplants, GRFS did not differ by timing:
- Up-front: 77%
- After IST failure: 76% (not statistically significant)
Clinical implications
- Pediatric SAA HSCT outcomes are excellent overall, with low graft failure and relatively low clinically significant GVHD.
- When a matched sibling is unavailable, up-front HSCT from a well-matched unrelated donor is a strong option.
- Modern HSCT after IST failure, using well-matched unrelated donors, now achieves outcomes approaching those of up-front transplantation.