In Vivo Accelerator-Based Boron Neutron Capture Therapy for Spontaneous Tumors in Large Animals: Case Series

Simple Summary Accelerator-based neutron sources for boron neutron capture therapy (BNCT) are potentially more accessible than nuclear reactors but many technical issues in clinical trials and further routine therapy remain to be studied. We aim to broaden the understanding of these issues with a study of BNCT in 10 cats and dogs, highlighting practical issues, using an accelerator-based neutron source. Using larger animals with tumors mimicking human clinical progression is an important intermediate step to clinical BNCT development. (1) Background: accelerator-based neutron sources are a new frontier for BNCT but many technical issues remain. We aimed to study such issues and results in larger-animal BNCT (cats and dogs) with naturally occurring, malignant tumors in different locations as an intermediate step in translating current research into clinical practice. (2) Methods: 10 pet cats and dogs with incurable, malignant tumors that had no treatment alternatives were included in this study. A tandem accelerator with vacuum insulation was used as a neutron source. As a boron-containing agent, B-10-enriched sodium borocaptate (BSH) was used at a dose of 100 mg/kg. Animal condition as well as tumor progression/regression were monitored. (3) Results: regression of tumors in response to treatment, improvements in the overall clinical picture, and an increase in the estimated duration and quality of life were observed. Treatment-related toxicity was mild and reversible. (4) Conclusions: our study contributes to preparations for human BNCT clinical trials and suggests utility for veterinary oncology.