Graft failure post allogeneic hematopoietic stem cell transplant in pediatric and young adults at a single centre in N. India

Background

Graft failure (GF) is a rare complication post hematopoietic stem cell transplant (HSCT) and failure to achieve a stable engraftment leads to increased risk of morbidity and mortality.

Procedure

We performed a retrospective observational study, on a cohort of patients transplanted from January 2019 to November 2024 to analyse potential risk factors for GF. All consecutive patients from 1 till 21 years of age who underwent allogeneic HSCT during the study period were included. Univariate analysis was done to determine the risk factors for GF. Overall survival (OS) was calculated using the Kaplan-Meier method and the differences in subgroups were assessed by log-rank test.

Results

336 patients between 1 and 21 years of age underwent allogeneic HSCT, out of which 16 (4.76 %) experienced GF. Eleven (68.75 %) had primary graft failure (PGF) and 5 (31.25 %) secondary graft failure (SGF). Univariate analysis of risk factors contributing to GF showed that cryopreservation of stem cell product significantly increased the risk of GF, which was 14.63 % (6/41) in cryopreserved infused product vs 3.38 % (10/290) in freshly infused product, P value=0.001. Given the small number of patients suffering graft failure, it was not possible to conclusively establish by multivariate analysis the relevance of other factors. At a median follow up of 794 days (22–2920), overall survival (OS) of patients with GF was significantly lower as compared to non-GF cohort (38.1 % vs 76.1 %, P value = 0.004).

Conclusion

We concluded that infusion of cryopreserved stem cell product remains a significant risk factor for GF which subsequently reflects poor OS, it was not possible to clearly define the impact of other variables on GF. Based on this analysis, moving ahead, we intend to change the policy to use freshly harvested stem cell products for all our allogeneic HSCT recipients.