The Australian paediatric brachytherapy experience: A pathway to a national programme.

Introduction: Paediatric cancers are rare, and most children requiring radiation therapy receive external beam radiation (EBRT). Although EBRT may offer organ preservation compared to surgery, it can be associated with significant late effects. Image-guided brachytherapy is a highly specialised technique offering both organ preservation and dose conformity to minimise late toxicity.

Methods: This is a retrospective mono-institutional review of paediatric brachytherapy in one of the largest paediatric centres in Australia. Outcomes and toxicities are presented as well as brachytherapy versus proton plan comparison in four patients.

Results: A total of 14 patients were treated with adjuvant brachytherapy between 2012 and 2022. The predominant histology was rhabdomyosarcoma, and all patients had pelvic tumours. High-dose rate (HDR) brachytherapy was given for 13 patients with one patient receiving low-dose rate (LDR) brachytherapy. Only one grade three late toxicity was reported and two patients developed metastatic disease within one year of completion of treatment. The brachytherapy plan was superior to protons in two of four patients and equivocal in one patient.

Conclusion: This is the first Australian publication of a paediatric brachytherapy series from a single institution. This retrospective series demonstrates the feasibility and safety of brachytherapy in paediatric pelvic tumours. The initial work presented here demonstrates the value of a comprehensive radiation plan review in selecting the optimal modality for an individual paediatric patient.