BNCT: a promising area of research?

The renewed interest in boron neutron capture therapy (BNCT) is driven mainly by the disappointing progress in the treatment of brain tumors by other modalities over the last decades. Even though molecular biology newer drugs and strategies may promise better results in the future, BNCT is an attractive approach. Brain tumors kill by local growth and not be metastases. Boron can be delivered to the tumor while normal brain is protected by the blood brain barrier, which can be disrupted to the degree desired. Tumor selectivity can be obtained not only by improved drug barrier, which can be disrupted to the degree desired. Tumor selectivity can be obtained not only by improved drug delivery but also by restricting the capture reaction to the region of interest by targeted radiation. Both boron drug and thermal neutrons alone are to some extent innocuous to tumor and normal tissues in this binary form of therapy. The pattern of treatment failure from uncontrolled primary tumor, the blood brain barrier protection of normal surrounding tissue and the limited range of epithermal neutrons explain why brain tumors are the main focus of BNCT research.