In Japan, because of the rapid increase in the number of thyroid cancer patients and the recent severe shortage of radioisotope therapy wards, the prolonged waiting time for the admission to the radioisotope therapy wards has become a social problem. This situation is against one of the main purposes of the Cancer Control Promotion Plan of our nation, which is advocating an equal accessibility of medical care for the Japanese citizens. In 2015, diet discussions about the problems of radioisotope therapy took place and the prime minister stated that the promotion of radioisotope therapy is one of the most important issues in Japan, therefore further promotion of research and development is anticipated in this field. In this article, we have summarized the problems during radioisotope therapy, and have added our recommendations in the social and medical realizable countermeasures in future, according to the deep considerations of medical economy in Japan, an assumption of disease prevalence of thyroid cancer in the future, and the situations of foreign countries.

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Indications for percutaneous coronary intervention (PCI) among patients with stable coronary artery disease (CAD) have historically been decided after morphological evaluation using coronary angiography (CAG). Recently, the importance of physiological evaluation has been recognized using either myocardial perfusion imaging (MPI) or fractional flow reserve (FFR). The results of the recent COURAGE trial showed that PCI did not improve mortality rates in medically optimized patients with stable CAD. However, a nuclear sub-study of that trial in which participants underwent MPI before and after PCI+ optimal medical therapy (OMT), found a greater reduction in ischemia compared with OMT alone. Moreover, the unadjusted risk for death or myocardial infarction in patients with ischemia reduction was lower. In contrast, the FAME study indicated that FFR-guided PCI improved the outcomes of patients with multi-vessel CAD compared with angiography-guided PCI. The FAME II study also indicated the validity of FFR-guided PCI. Thus, FFR evaluation of ischemia is becoming more popular worldwide from the viewpoint of intervention. Both MPI and FFR reflect physiological ischemia, but their findings do not necessarily match up. One reason is that MPI reflects myocardial ischemia whereas FFR reflects coronary artery ischemia. Thus, cardiologists regard the findings of these modalities conflicting when considering practicality and diagnostic accuracy. This article compares the features of MPI and FFR and discusses an appropriate strategy with which to evaluate CAD.

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We evaluated the significance of dietary instruction (DI) for patients who are going on a low iodine diet (LID) as a preparation for remnant tissue ablation for thyroid cancer. DI was done by a dietarian using a dedicated handbook we have developed. To assess the effect of LID on depleting body iodine, urinary iodine concentration (UIC) in patients with post-surgical papillary thyroid cancer was measured twice, before and after LID. UIC on the day of radioiodine administration was compared with radioiodine uptake (RU) in the remnant tissue. Additionally, the association between clinical and lifestyle-related features of patients and the outcome of LID were investigated. A questionnaire survey was conducted to determine whether the DI helped patients go on LID. The mean value of UIC after the one-week LID was decreased to about 15% of the baseline value. There was a significant inverse correlation between UIC and RU (r= −0.694). Age and UIC before the start of LID were linked to successful outcome of LID. In the questionnaire survey, 84% of the participants answered that the handbook helped them go on a LID. Likewise, 80% answered that they could manage their LID without using the boil-in-the-bag low iodine food. LID successfully decreased UIC in patients undergoing remnant tissue ablation. DI by a dietitian may make a practice of LID easier.

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To maintain sterility of PET drug is the most important for in-house positron emission tomography (PET) drug manufacturing, and sanitary control of the laboratory to perform aseptic procedure is the key point for the sterility of PET drugs. However, rigorous sanitary control affects both the high cost and the low efficiency. To conquer those, we developed an isolator system especially for PET drug compounding including sterilization and dispensing units. This system consists of a HEPA unit for inlet and outlet, positive regulation of the ear inside isolator, a sterilizer with vapored hydrogen peroxide and a dispenser with self-shield for radiation. We set the materials for the dispenser through gloves, and the compounding such as sterilization and dispensing PET drugs to the containers is performed automatically without radiation. High level assurance of PET drug sterility is expected to be accomplished in the PET centers of the hospitals without high level sanitary control.

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The aim of this study was to examine whether the heart rate response to adenosine differs after 12 hours [Good control (Good-C)] versus 24 hours [Excellent control (Exc-C)] of caffeine abstinence in adenosine stress thallium-201 (TL) myocardial perfusion imaging (MPI). Patients (n=729) with suspected ischemic heart disease underwent adenosine TL-MPI after 12 (n=226) and 24 (n=503) hours of caffeine abstinence. There was not significant differences between the heart rate of Exc-C and Good-C in 0–2 min after adenosine infusion (0 min 63.7±9.5 versus 63.7±10.0, 1 min 66.4±10.6 versus 65.3±10.5, 2 min 72.3±11.2 versus 70.6±11.4). The heart rate of Exc-C was higher compared to Good-C in 3–6 min after adenosine infusion (3 min 75.6 ±11.7 versus 73.3±11.6 p=0.013, 4 min 79.2±12.9 versus 76.7±12.2 p=0.012, 5 min 79.4±12.6 versus 76.8±12.4 p=0.009, 6 min 79.4±12.5 versus 77.0±12.3 p=0.016). Therefore, the longer caffeine abstinence, namely 24 hours self-restraint, is effective in adenosine TL-MPI.

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This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2014 in Japan. It was based on the responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 992 institutions among 1,244 to which the questionnaire had been sent. Nine cases of adverse reactions were reported. A total of 1,091,011 radiopharmaceutical administrations were reported. The incidence of adverse reactions per 100,000 case was 0.8. Three cases of deficient products were reported, and the incidence of deficient products per 100,000 case was 0.3.

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[in Japanese]

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