Evaluation of performance of an accelerator-based BNCT facility for the treatment of different tumor targets

Abstract

Purpose: Encouraging Boron Neutron Capture Therapy (BNCT) clinical results obtained in recent years have stimulated intense research to develop accelerator-based neutron sources to be installed in clinical facilities. In this work an assessment of an accelerator-based BNCT facility for the treatment of different tumor targets was performed, comparing the accelerator-derived results with reported reactor-based trials under similar conditions and subjected to the same clinical protocols.

Materials and methods: A set of real image studies was used to cover clinical-like cases of brain and head-and-neck tumors. In addition, two clinical cases of malignant nodular melanoma treated at the RA-6 BNCT facility in Argentina were used to thoroughly compare the clinical dosimetry with the accelerator-derived results.

Results: The minimum weighted dose delivered to the clinical target volume was higher than 30 Gy and 14 Gy for the brain tumor and head-and-neck cases, respectively, in agreement with those achieved in clinical applications. For the melanoma cases, the minimum tumor doses were equal or higher than those achieved with the RA-6 reactor for identical field orientation and protocol. The whole-body dose assessment showed that the maximum photon-equivalent doses for those normal organs close to the beam direction were below the upper limits considered in the protocols used in the present work.

Conclusions: The obtained results indicate not only the good performance of the proposed beam shaping assembly design associated to the facility but also the potential applicability of accelerator-based BNCT in the treatment of both superficial and deep-seated tumors.

Keywords: Accelerator-based neutron source; Treatment planning assessment; Whole-body dose assessment.