Abstract
The ideal radiotherapy in 20th century is to deliver more doses to cancer region as confined as possible. This has been proved to be true by the success of brachytherapy. Recent advance of accelerator, computer and medical imaging have enabled this idea even by external x-ray beam. 3D-radiotherapy, intensity modified radiotherapy (IMRT) and heavy charged particle radiotherapy are example. However, this idea is not universally true. It may be true if the cancer arises in parallel organs, but not if the cancer is in serial organs. The more universal idea that must be adopted in 21st century is to deliver more doses to cancer cells as confined as possible. α particle and Li nucleus that are emitted by 10B(n, α)7Li reaction have very short track and high LET character. Therefore, if 10B compound accumulates in cancer cells selectively, only cancer cells are destroyed. Malignant glioma and melanoma are successfully treated by this boron neutron capture therapy. Advanced recurrent head and neck cancers also dramatically shrank without significant skin reaction. [J Radiat Res 44:377-378 (2003)]
