Transcending history: The revolution of TMLI in BMT
Keywords:
Total Body Irradiation, TBI, Bone Marrow Transplant, Acute Leukaemia, Inotuzumab, Haemato-oncologyAbstract
Background: Total Marrow and Lymphoid Irradiation (TMLI) is an organ-sparing alternative to Total Body Irradiation (TBI) in conditioning for bone marrow transplantation (BMT), offering precise radiation targeting of marrow and lymphoid tissues.
Case Presentation: We report a case of Relapsed Philadelphia-Positive B-cell Acute Lymphoblastic Leukemia (B-ALL) with T315I mutation who underwent consolidation allogeneic stem cell transplantation with TMLI-based conditioning.
Methods: TMLI was delivered at 13.5 Gy in 9 fractions (2 fractions per day – 6 hours apart for 5 days) using multiple VMAT plans on a Varian TrueBeam Linear Accelerator. Target volumes included the entire skeletal and lymphatic systems.
Results: The patient tolerated treatment well, with only grade II mucositis. Neutrophil and platelet engraftment occurred on Days +11 and +13, respectively. No infections were observed post-transplant. Chimerism analysis on Days +30 and +60 confirmed 100% donor cell engraftment. She remains clinically stable at last follow-up.
Conclusion: This case illustrates the feasibility, safety, and clinical efficacy of TMLI as part of a myeloablative conditioning regimen for high-risk ALL. TMLI offers precise dose delivery to hematologic targets with reduced toxicity, representing a promising modality in contemporary transplant conditioning
