Boron Neutron Capture Therapy

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Apart from the above example, there have been malignant meningioma cases in which good tumor response has been achieved. This pathological type of tumor is refractory to X-ray therapy. (Photo: A case at Osaka Medical College.)In one case where surgery was conducted after BNCT, the complete degeneration of the tumor was conrmed by histopathological examination, while the parotid gland and fat cells remained without destruction (despite lying inside the neutron irradiation eld). (Photo: A case at Kawasaki Medical School.) It is a case that conrms the selective effects of BNCT at the microscopic level.This is the world’s rst MPM to be treated with BNCT. The treatment proved to be remarkably effective. (Photo: A case at Hyogo Prefectural Amagasaki Hospital.) The patient had suffered from severe chest pain and needed to use morphine every day, but the pain disappeared completely several days after BNCT. Regression of the tumor was conrmed by CT six months later, and the patient lived for 10 months, far beyond initial expectation of less than three months.The black spot lesion had completely degenerated, and normal skin regenerated at a high level of quality. (Photo: A case of malignant melanoma at Kawasaki Medical School.) FBPA excreted in the salivaFBPA excreted in the salivaAccumulation ofFBPA inthe tumorAccumulation ofFBPA inthe tumor5 days after BNCT5 days after BNCT6 months after BNCT6 months after BNCTBefore BNCTAfter BNCTBecause the cancer has spread along the pleura in cases of MPM, the tumor presents a complicated, three-dimensional geometry. Consequently, it is impossible to irradiate the tumor with a controlled dose while avoiding the lungs, which are covered with tumors, even using today’s high-precision radiation treatment technologies. Experts hope that treatment techniques such as BNCT to offer a high level of tumor selectivity that will provide superior effectiveness in MPM.The standard treatment regimen for head and neck cancers combines surgery, X-ray therapy, and chemotherapy. BNCT is expected by radiation oncologists to serve as a technique that makes possible repeated radiation therapy for recurrent patients because re-irradiation by X-rays is not allowed due to the tolerance dose of normal tissue consumed during previous X-ray therapy.The world's first use of BNCT to treat a head and neck cancer was a case of recurrent cancer of the parotid gland. After two BNCT treatments, the tumor had completely regressed, and the patient’s skin reaction did not reach to the level of dry desquamation. (Photo: A case at Osaka University.) It is not possible with other treatment modalities to avoid damage such as thin and blistered skin while irradiating enough of a control dose to the tumor lying just under the skin. The responses observed in this case showed BNCT’s high degree of tumor selectivity and its superiority. BPA was developed clinically as a boron compound for use with malignant melanoma of the skin, and its tendency to accumulate at high concentrations in melanoma lesions has been confirmed. While surgical removal has proven adequate for treating small lesions, BNCT using BPA is an effective new treatment in cases where the area of removal is large or where removal would lower the patient’s quality of life.Center of tumor : ScarrHealthy parotid gland inside the neutron irradiation eldPioneering and excellent clinical results in JapanThere are high expectations concerning BNCT research targeting treatment of malignant brain tumors, particularly malignant glioma.Since BNCT allows a large radiation dose to be administered at once, there are cases in which the tumor reacts (as evidenced by the degeneration and disappearance of the lesions in MRI ) much more quickly (in about two days), unlike in X-ray therapy. (Photo: A case at Osaka Medical College.)Malignant brain tumorsMalignant pleural mesothelioma (MPM)Head and neck cancersMalignant melanoma of the skinNeither X-ray therapy nor other types of particle therapy are applicable to multiple liver cancer, and there is no treatment that offers the possibility of a permanent cure. Since it is necessary to irradiate the entire liver, we believed that this type of cancer would be a good candidate for BNCT, which can be expected to selectively destroy such tumors, and we attempted clinical BNCT in several cases based on the results of BSH tumor trapping experiments as described above. We were able to confirm a certain level of effectiveness, but it remained insufficient. We are current-ly waiting for a new technique to be developed. Similarly, by using BPA we attempted BNCT for patients with carcinomatous pleurisy, in which the cancer has spread throughout the pleura, and obtained comparatively favorable results. In many cases, Paget disease, a type of skin cancer, spreads over a large area, and surgical removal would lower quality of life (as is the case with malignant melanoma). We have experienced several cases that show the usefulness of BNCT for this disease. Otherwise, BNCT has been successful when cancer has metastasized to the lymph nodes and accompanied by strong symptoms in patients who have previously undergone X-ray therapy in the same region of the body.Experiments and preliminary clinical trials of BNCT for other types of tumors5

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