Fludarabine - Total Body Irradiation-Based Myeloablative Conditioning for Haploidentical Hematopoietic Stem Cell...

The data on outcomes of haploidentical hematopoietic stem cell transplantation (haplo-HSCT) with Fludarabine-Total Body Irradiation (Flu-TBI) based myeloablative conditioning from resource-limited countries is sparse. This study evaluated Flu-TBI based myeloablative conditioning with post-transplant cyclophosphamide (PTCy) for haplo-HSCT, focusing on graft-versus-host-disease (GVHD)-free relapse-free survival (GRFS), relapse-free survival (RFS), non-relapse mortality (NRM), and overall survival (OS). We retrospectively analyzed 42 patients at a South Indian tertiary cancer center from August 2015 to May 2024. Patients, mostly with acute leukemia, received Flu-TBI' and PTCy for GVHD prophylaxis. Data on characteristics, toxicities, GVHD, and outcomes were collected. Survival was assessed via the Kaplan-Meier method. Median age was 16.5 years (60% male). The 2-year GRFS was 41.1%, RFS was 50.6%, and OS was 52.0%. Day 100 NRM occurred in 28.5% (n = 12). Acute GVHD (grade 3-4) and chronic GVHD (extensive) incidences were 14% and 10%, respectively. Severe hemorrhagic cystitis, related to BK-virus reactivation, affected only 7% (n = 3). Multivariate analysis showed that female donors were associated with significantly worse GRFS (HR 2.58, 95%CI 1.1-6.2, p = 0.03). Flu-TBI with PTCy is an effective haplo-HSCT regimen, yielding acceptable survival and low hemorrhagic cystitis risk. Female donors notably reduce GRFS, suggesting male donor preference when feasible.

The online version contains supplementary material available at 10.1007/s12288-025-02072-1.