For shielding beta-rays, Bremsstrahlung generated inside the shield must be taken into account. In the past, Bremsstrahlung has been presumed to be generated uniformly at the surface of the shield opposite to incident direction. In reality, however, Bremsdstrahlung is generated inside the shield and attenuated until it reaches opposite surface to incident direction of beta-rays. In this paper, effective dose rate constants in shielding materials with and without attenuation in the shield were calculated for 13 important radionuclides(3H, 63Ni, 14C, 35S, 147Pm, 33P, 45Ca, 90Sr, 85Kr, 36Cl, 89Sr, 32P, and 90Y)and for 6 important shielding materials(water, concrete, aluminum, iron, tungsten, and lead). In addition, effective dose transmission rate with and without attenuation were calculated for the same radionuclides and shielding materials.
Radionuclide therapy with unsealed source strontium-89chloride injection requires physicians or the like who have adequate knowledge and experience as to anti-cancer chemotherapy, radiation therapy, nuclear medicine, etc. as well as adequate facilities, equipment and safety management system. The Japanese Society of Nuclear Medicine and the Japanese Society for Therapeutic Radiology and Oncology recently conducted an economic evaluation, based on medical technology assessment, about pain relief therapy using strontium-89 chloride injection at 54 facilities, with a goal of technological and economic assessment of radionuclide therapy. The results suggest the necessity of improving the current reimbursement system under national health insurance so that the cost (2 480 ten for five times) for this therapy at the medical facilities can be appropriately reimbursed from the insurer to facilitate proper spread of this therapy.
Radioimmunotherapy with unsealed source 90Y-ibritumomab tiuxetan requires physicians and paramedics who have adequate knowledge and experience as to anti-cancer chemotherapy, radiation therapy, handling of radioactive materials, etc. as well as adequate facilities, equipments and safety management system. The Japanese Society of Nuclear Medicine and the Japanese Society for Therapeutic Radiology and Oncology recently conducted an economic evaluation about radioimmunotherapy using 90Y-ibritumomab tiuxetan based on the medical technology assessment at the 16 medical facilities. As a result of this survey, the necessity to improve the current reimbursement system under national health insurance has been suggested, so that the cost(4 450 ten for five times)for this therapy at the medical facility can be appropriately reimbursed for the proper dissemination of this therapy.
The clinical value of 11C-Choline-PET is reviewed by using previously published articles with significant evidence levels. This meta-analysis indicates that 11C-Choline-PET showed a high ability for the diagnosis of primary tumor, clinical staging and detection of recurrence. Especially, in patients with suspected metastasis or recurrence, 11C-Choline-PET was able to detect foci of diseases, which were not evident by morphological imaging modalities. Thus, 11C-Choline-PET may have a potential to afford important information for the management of such patients and yield cost-effectiveness by obviating unnecessary examinations.