Clinical Report: Boron Neutron Capture Therapy for Recurrent Meningiomas

Overview

This retrospective study evaluates the dosimetric parameters and clinical outcomes of boron neutron capture therapy (BNCT) in 13 patients with recurrent meningiomas. BNCT demonstrated selective tumor targeting with acceptable safety profiles, offering a promising salvage treatment option for recurrent cases where conventional therapies are limited.

Background

Meningiomas are the most common primary intracranial tumors, with subtypes ranging from benign to anaplastic forms. Surgical resection is the mainstay of treatment, but complete removal is often challenging due to tumor location and invasiveness. Recurrent meningiomas pose therapeutic challenges, particularly when prior radiotherapy limits re-irradiation options. BNCT offers a novel approach by selectively destroying tumor cells through boron-10 neutron capture reactions, minimizing damage to surrounding healthy tissue.

Data Highlights

Key Findings

• BNCT was administered as salvage therapy for recurrent meningiomas with a minimum TNR of 2.0 or 2.5 depending on PET tracer used.
• Tumor dose planning incorporated PET-derived TNR values to optimize selective targeting.
• Response evaluation at 3 months post-BNCT used RANO criteria, categorizing patients as responders (CR/PR) or non-responders (SD/PD).
• BNCT treatments adhered to strict brain dose constraints to minimize neurological toxicity.
• Preliminary clinical outcomes suggest BNCT can achieve tumor control in recurrent meningiomas refractory to conventional therapies.

Clinical Implications

BNCT represents a viable salvage treatment for recurrent meningiomas, especially when prior radiotherapy limits further conventional options. Incorporating PET imaging for boron uptake assessment is critical for patient selection and dose planning. Clinicians should consider BNCT in multidisciplinary management of recurrent meningiomas to optimize tumor control while preserving neurological function.

Conclusion

BNCT offers a promising targeted therapeutic modality for recurrent meningiomas, demonstrating favorable dosimetric profiles and encouraging clinical outcomes. Further prospective studies are warranted to validate its efficacy and long-term safety.

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