ESTRO ACROP and SIOPE recommendations for myeloablative Total Body Irradiation in children

Radiother Oncol. 2022 Aug;173:119-133. doi: 10.1016/j.radonc.2022.05.027. Epub 2022 May 31.

Abstract

Background and purpose: Myeloablative Total Body Irradiation (TBI) is an important modality in conditioning for allogeneic hematopoietic stem cell transplantation (HSCT), especially in children with high-risk acute lymphoblastic leukemia (ALL). TBI practices are heterogeneous and institution-specific. Since TBI is associated with multiple late adverse effects, recommendations may help to standardize practices and improve the outcome versus toxicity ratio for children.

Material and methods: The European Society for Paediatric Oncology (SIOPE) Radiotherapy TBI Working Group together with ESTRO experts conducted a literature search and evaluation regarding myeloablative TBI techniques and toxicities in children. Findings were discussed in bimonthly virtual meetings and consensus recommendations were established.

Results: Myeloablative TBI in HSCT conditioning is mostly performed for high-risk ALL patients or patients with recurring hematologic malignancies. TBI is discouraged in children <3-4 years old because of increased toxicity risk. Publications regarding TBI are mostly retrospective studies with level III-IV evidence. Preferential TBI dose in children is 12-14.4 Gy in 1.6-2 Gy fractions b.i.d. Dose reduction should be considered for the lungs to <8 Gy, for the kidneys to ≤10 Gy, and for the lenses to <12 Gy, for dose rates ≥6 cGy/min. Highly conformal techniques i.e. TomoTherapy and VMAT TBI or Total Marrow (and/or Lymphoid) Irradiation as implemented in several centers, improve dose homogeneity and organ sparing, and should be evaluated in studies.

Conclusions: These ESTRO ACROP SIOPE recommendations provide expert consensus for conventional and highly conformal myeloablative TBI in children, as well as a supporting literature overview of TBI techniques and toxicities.

Keywords: Consensus recommendations; Hematopoietic stem cell transplantation; Pediatric; Total Body Irradiation.

MeSH terms

  • Bone Marrow
  • Child
  • Child, Preschool
  • Hematopoietic Stem Cell Transplantation* / adverse effects
  • Hematopoietic Stem Cell Transplantation* / methods
  • Humans
  • Retrospective Studies
  • Transplantation Conditioning / methods
  • Whole-Body Irradiation* / adverse effects
  • Whole-Body Irradiation* / methods