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Boron neutron therapy has been able to treat a variety of cancers, including advanced recurrent cancers, such as malignant primary brain tumors, liver tumors (including several lesions), head and neck tumors (tongue cancer, laryngeal cancer, pharyngeal cancer, oral cancer, thyroid cancer, parotid cancer, external ear cancer and middle ear cancer), colon cancer, bladder cancer, locally recurrent breast cancer, lung cancer, melanoma and mesothelioma. BNCT radiotherapy requires that boron drugs have strong tumor chemotaxis, that is, the ratio of boron absorbed by tumor to normal tissue (T/N) and the ratio of boron concentration between tumor and blood (T/B) are much greater than 3. In the second generation of boron drugs, the T/N of L-p- boracylphenylalanine (BPA) is 3~4, and the T/B is about 3, which can not only cross the brain barrier, but also directly enter cancer cells. Disodium dodecyl borate (BSH), whose T/N is 10 and T/B is about 1.5, can't pass through the blood-brain barrier, but it can accumulate in tumor tissue after the blood-brain barrier is destroyed. The second generation drugs BPA and BSH have been proved to be effective through a large number of clinical applications. When the new boron drug is only enriched in the tumor, BNCT really achieves the goal of blasting the tumor without damaging the surrounding normal tissues. Cell-level lethality. When the tumor site is irradiated with epithermal neutrons, the epithermal neutrons enter human tissues, and the neutrons react with boron-10 nuclei in cancer cells, releasing α(4He) particles and 7Li particles, which have a strong killing effect on cells, and the killing effect is much higher than that of photon radiotherapy and proton radiotherapy. The released α particles and 7Li particles have short flight distances (γ-rays, protons and heavy ions are mainly used for external irradiation therapy, but they are used for huge local tumors without diffusion and metastasis. Chemotherapy and targeted radionuclide therapy are mainly used for systemic treatment, aiming at immune system tumors. BNCT is a dual treatment mode, which mainly achieves the therapeutic effect through the combination of neutrons and boron-10, rather than simply chemotherapy+radiotherapy. Remember the suspected binary VX nerve gas incident in Malaysia on the Internet? BNCT has a good therapeutic effect on diffuse or metastatic tumors with tissue infiltration and diffusion characteristics.