ESTRO 2025 - Abstract Book

S924

Clinical - Haematology

ESTRO 2025

mycophenolate mofetil as GVHD prophylaxis. Patients were followed for a minimum of 3 months, collecting relevant clinical and analytical data. Data analysis was performed with STATA (StataCorp LP). Results: Thirty-six patients receiving radiotherapy as part of conditioning treatment for allo-HPT for B-ALL were included. Sixty four percent of patients (n=23) were in second complete or subsequent response. Of these, 24 (67%) patients received TBI while in 12 (33%) patients TMLI was performed. The median age for the TBI group was 18 years (8-22) and 25 years (18.5-36.5) for the TMLI group. The majority of allo-HPT were haploidentical donor (42% in the TMLI group and 66% in the TBI group). 2.7% rejection of the transplant was obtained. No differences between the TBI and TMLI cohorts were seen in terms of engraftment. No organ toxicity was observed in the first months after transplantation in either cohort. Conclusion: The preliminary finding was that TBI can be safely replaced by TMLI in terms of engraftment, GVHD incidence, and extrahematologic toxicities. Further studies with larger cohorts are required to confirm these findings.

Keywords: TMLI, Acute Lymphoblastic Leukemia